13-31

Atmospheric Pollution Records in Forest of
Bowland Peats
Elanor Brown
2016
Edge Hill University
A dissertation submitted to Edge Hill University in partial fulfilment of requirements for the
Degree of Environmental Science, Bachelors of Science.
This is an original piece of work conducted using my own samples in conjunction with
previously written reports and information sources.
This dissertation may be made available for photocopying and for inter-library loans by Edge
Hill University.
Signed:
Elanor Brown 22510648
2016

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Abstract
Peat can retain information on environmental change over varying timescales, in this study
approximately the last 200 years are examined, specifically for atmospheric pollution. The three
variables that are examined are magnetic mineral measurements (SIRM, Reverse field ratios and
SIRM/ARM), Spheroidal Carbonaceous Particles (SCPs), soot particulates, and a selection of heavy
metals including Lead, Iron, Zinc and Copper. The aim of the research is to allow for investigation
into the reliability of magnetic records against SCP records, if the magnetic record has been affected
by dissolution has the SCP record been similarly affected? The research will also look to see if there
is a difference in pollution with distance from the urban areas of Manchester and Bolton. The Trough
of Bowland has not been recently investigated, and it certainly has not been studied for atmospheric
pollution before. The study area stretches over Northern Lancashire, the four sites examined include
Abbeystead, Bleasdale, Bentham and Pendle. The findings suggest that there has been some
movement and dissolution of the particulates; which in return has shown that there are
inconsistencies with the distance decay trend outlined by Thompson and Oldfield (1986) and Marx et
al. (2010). The processes that may have caused this to happen are then discussed, these include:
dryness, mobility of metals, and initial deposition. The SCP relationship with magnetics does not
indicate corroboration with the other two variables.

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Table of Contents
Abstract...................................................................................................................................................1
Table of Figures.......................................................................................................................................4
List of Plates............................................................................................................................................6
List of Tables ...........................................................................................................................................6
Acknowledgements.................................................................................................................................6
1.0 Introduction ......................................................................................................................................7
1.1 Aims and Objectives....................................................................................................................15
2.0 Methods..........................................................................................................................................16
2.1 Location.......................................................................................................................................16
2.2 Field Methods .............................................................................................................................19
2.3 Laboratory Methods ...................................................................................................................20
2.31 XRF ........................................................................................................................................22
2.32 SCP Preparation ....................................................................................................................22
2.33 Magnetic Mineral Measurements ........................................................................................23
3.0 Results.............................................................................................................................................25
3.1 Bleasdale - Core 1........................................................................................................................25
3.11 Magnetics..............................................................................................................................25
3.12 XRF ........................................................................................................................................26
3.2 Abbeystead - Core 2....................................................................................................................30
3.21 Magnetics..............................................................................................................................30
3.22 XRF ........................................................................................................................................31
3.3 Bentham - Core 3 ........................................................................................................................35
3.31 Magnetics..............................................................................................................................35
3.32 SCPs.......................................................................................................................................36
3.33 XRF ........................................................................................................................................37
3.4 Pendle Hill - Core 4......................................................................................................................40
3.41 Magnetics..............................................................................................................................40
3.42 SCPs.......................................................................................................................................41
3.43 XRF ........................................................................................................................................42
4.0 Results Description .........................................................................................................................45
4.1 Bleasdale - Core 1........................................................................................................................45
4.12 Bulk Density ..........................................................................................................................46

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4.13 Heavy Metals.........................................................................................................................46
4.2 Abbeystead - Core 2....................................................................................................................47
4.22 Bulk Density ..........................................................................................................................48
4.23 Heavy Metals.........................................................................................................................48
4.3 Bentham - Core 3 ........................................................................................................................49
4.32 Bulk Density ..........................................................................................................................50
4.33 SCP Concentration ................................................................................................................50
4.34 Heavy Metals.........................................................................................................................50
4.4 Pendle Hill - Core 4......................................................................................................................51
4.42 Bulk Density ..........................................................................................................................52
4.43 SCP Concentrations...............................................................................................................52
4.44 Heavy Metals.........................................................................................................................53
5.0 Explanation .....................................................................................................................................54
5.1 Bleasdale Core 1..........................................................................................................................54
5.12 Heavy Metals.........................................................................................................................54
5.13 Bulk Density ..........................................................................................................................55
5.2 Abbeystead - Core 2....................................................................................................................55
5.22 Heavy Metals.........................................................................................................................56
5.23 Bulk Density ..........................................................................................................................56
5.3 Bentham - Core 3 ........................................................................................................................57
5.32 SCPs.......................................................................................................................................57
5.33 Heavy Metals.........................................................................................................................57
5.34 Bulk Density ..........................................................................................................................58
5.4 Pendle Hill - Core 4......................................................................................................................58
5.42 SCPs.......................................................................................................................................59
5.43 Heavy Metals.........................................................................................................................59
5.44 Bulk Density ..........................................................................................................................59

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6.0 Comparison.....................................................................................................................................60
6.1 Magnetic Minerals ......................................................................................................................60
6.2 Heavy Metals ..............................................................................................................................62
6.3 SCPs.............................................................................................................................................64
7.0 Discussion........................................................................................................................................65
7.1 Distance Decay............................................................................................................................65
7.2 Movement of Metals ..................................................................................................................65
7.3 Dissolution of Magnetics.............................................................................................................66
7.4 SCP record against the Magnetics ..............................................................................................67
8.0 Conclusion.......................................................................................................................................68
9.0 Reference List..................................................................................................................................70
Table of Figures
Figure 1: Map of the North West of England centred on the Forest of Bowland AONB- Page 17
Figure 2: Location of the cores within the Forest of Bowland- Page 18
Figure 3: SIRM and reverse field ratios for core 1- Page 25
Figure 4: SIRM/ARM for core 1- Page 26
Figure 5: Bulk density changes for core 1- Page 26
Figure 6: Iron concentration against depth for core 1- Page 26
Figure 7: Copper concentration against depth for core 1- Page 27
Figure 8: Zinc concentration against depth for core 1- Page 27
Figure 9: Lead concentration against depth for core 1- Page 27
Figure 10a: Iron concentration against SIRM for core 1- Page 28
Figure 10b: Copper concentration against SIRM for core 1- Page 28
Figure 10c: Zinc concentration against SIRM for core 1- Page 28
Figure 10d: Lead concentration against SIRM for core 1- Page 29

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Figure 22: SCP concentrations for core 3- Page 36
Figure 31: SCP concentrations for core 4- Page 41

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List of Plates
Plate 1: PVC core inserted into the peat at Abbeystead- Page 19
Plate 2: A core removed from the PVC tube, ready for slicing- Page 20
List of Tables
Table 1: the varying magnetic parameters used in this study and their meanings- Page 23
Table 2: quantity of pollution, from SIRM and lead pollution, for each core- Page 60
Acknowledgements
I cannot thank Dr Nigel Richardson enough for the many hours of help and guidance that he has
freely given me during this dissertation.

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I would also like to thank Rob Hart for the many hours of laboratory time he assisted me with; 9am
to 7pm with half an hour for lunch would have been very boring without your sense of humour.
I would like to say thank you to the team from Lancashire County Council including Sarah Robison,
Tarja Wilson and Dave Padley, for organising all the necessary permissions, as well as helping me out
in the field, it is very much appreciated.
I would also like to thank Pete Wilson, from Untied Utilities and Graham Walsh from Natural England
for granting permissions for works on Bentham and in the SSSI.
And thanks to my mum, for the help she has given me with fieldwork and for just being a good
listener.
1.0 Introduction
Since the 1850s and the beginning of the British Industrial revolution atmospheric emissions as a
whole have increased significantly (Yang et al., 2001), this includes solid particulates, for example
soot and metals as well as gaseous pollutants such as CO2. Some emissions have decreased since the
1970s, including Cd and Pb (Yang et al., 2001), however work has shown reduction in air emissions

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does not show corresponding pollutant changes in peat which suggests either movement of
particulates in peat or longer term persistence of particulate pollution (Martı́nez Cortizas et al.,
2002). Four periods of atmospheric pollution have been identified, Roman, Early Middle Ages, Early
Modern and Industrial Revolution (De Vleeschouwer et al., 2007, Marx et al., 2010). Lead is the
earliest form of pollution and the first instances of it occurring were during Roman times, the
pollution was from local influences, more modern pollutants come from further afield (De
Vleeschouwer et al., 2007), the earliest dated atmospheric pollutants were produced around 900BC
(Marx et al., 2010).
Peat bogs are multi-dimensional archives; this is because they can preserve changes in the
atmosphere, lithosphere and the hydrosphere, on local, regional and global systems along different
timescales (Martı́nez Cortizas et al., 2002). Particulates can travel great distances due to
atmospheric motion (Marx et al., 2010). Of all the archives, peats, ice cores, lake sediments, deep
sea sediments, wind-blown sediments, cave sediments, glacial and periglacial sediments only peat,
lake and ice cores contain mean records of changing atmospheric quality (Bao et al., 2010). The
reason why ombrotrophic peat contains atmospheric data is because ombrotrophic peat bogs are
domed and are therefore cut off from the local water supply; their only input is from the
atmosphere (Bao et al., 2010, Olid et al., 2010). Lake sediments are only useful when the input from
the catchment is minimal, otherwise catchment soil type and other non-atmospheric data is
included, causing atmospheric quality data to mix with catchment data, lowering the accuracy of
findings (Oldfield et al., 2015) There has only been a very select amount of work done on ice cores in
Greenland and Antarctica, compared to peat, this is because peat is more accessible (Oldfield, 2015).
According to Oldfield (2015) the best environmental archives are those that are widespread,
accessible and have fairly rapid and continuous accumulation. Knowing the rate of accumulation is
important because it enables the knowledge on retention and deposition to be more accurate
(Oldfield, 2015). Any atmospheric data that is being used as a marker for environmental change in
the Anthropocene must be produced as a result of anthropogenic archives and once taken in, the

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marker must be retained (Oldfield, 2015). In the past peat cores have been separated into three
zones of accumulation, the Minerogenic zone, and Pre-industrial zone and Post -industrial zone
(Hutchinson and Armitage, 2005).
There are many advantages and disadvantages to using the two most accessible terrestrial archives,
lake sediments and peats. Lakes sediments and peat are good archives of past environmental data
because they are widespread and particulates accumulate with sufficient rapidity (Oldfield, 2015).
The first comparison that suggests peat keeps a better record of changing atmospheric quality is that
lake sediment contains material from the catchment, so there is more information than is needed,
this means finding the data that is required is more difficult, because peat input is purely from the
atmosphere it means that the data is limited in what it holds, but the source is definitive (Oldfield,
2015, Oldfield et al., 2015). However, the main advantage of lake sediment is that once deposited
the sediment is not affected by changes in chemistry, so it will provide an intact record, unless
affected by bioturbation (Rose et al., 1999). Peat can be affected by changes in the water table, it
has been shown that marker materials dissolve (Williams, 1992); records are known to be more
reliable in drier peat (Oldfield, 2015). Rothwell and Lindsay (2007) suggested that peat provides
generally good reliable data as long as it has not been taken from bare patches or eroded areas. It is
unfortunate that many of England’s upland areas under SSSI protection are in poor condition due to
over grazing, drainage and burning (Hutchinson and Armitage, 2005). The length of an archive
indicates the accumulation rate, for example a shorter core indicates a slow accumulation (Rose et
al., 1999), and in order for cores with differing accumulations to be compared it is customary to
convert concentrations into accumulations (Rose et al., 1999). Background levels of pollutants are
important because they must be known before the atmospheric influence can be considered.
Because peat can only take in particulates from the atmosphere it is acceptable to assume that there
are no significant background values; with lake sediments in order to complete analysis have to
remove particulates that have come from the catchment (Oldfield et al., 2015). For magnetic mineral
background levels there is some evidence that ferrimagnetic material can be formed in situ from

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non-magnetic minerals in peat (Oldfield et al., 2015). Rose et al., (1999) suggested that there may be
a background SCP concentration and compared it to background radiation.
High temperature combustion of fossil fuels produces both gaseous and solid pollutants (Rose et al.,
1999), other sources of solid pollution particulates that peat can record are vehicle emissions and
metal smelting (Oldfield et al., 2015, Rothwell et al., 2010, Nagafuchi et al., 2009). The solid material
is known as fly ash, which is made up of inorganic ash spheres (IAS) and organic spheroidal
carbonaceous particles (Oldfield et al., 2015, Nagafuchi et al., 2009). Work has been completed to
use peat archive data alongside written archives to match up pollution records from factories
(Oldfield et al., 1981). IASs are produced as a result of secondary reactions between minerals when
the fuels are burnt (Rose et al., 1999, Rothwell and Lindsay, 2007), the majority of IAS comes from
the burning of coal as oil does not contain as many impurities (Nagafuchi et al., 2009), coal was the
main fuel in the British Industrial Revolution (Oldfield et al., 2015). The iron impurities are oxidised
during high temperature combustion, the two main ones particular to this study are Magnetite
which is Fe3O4, and Haematite which is Fe2O3 (Rothwell and Lindsay, 2007). Spheroidal
Carbonaceous Particles (SCPs) are the result of incomplete combustion of fuel and they have no
natural sources so provide an unambiguous record of anthropogenic activity (Rose et al., 1999,
Oldfield et al., 2015). Both magnetic minerals and SCP records have been reported to have similar
patterns of distribution within an archive with other contaminants, for example sulphur (Rose et al.,
1999). The ash spheres are also much smaller particles than the carbon particles (Nagafuchi et al.,
2009, Oldfield, 2015). IAS are made up of magnetite, haematite and heavy metals (Oldfield et al.,
2015), they can be measured for mineral grain size and type by magnetic mineral measurements
(Oldfield et al., 2015). Many authors have suggested that lead is found in higher quantities than
other heavy pollutants is due to coal mining and burning releasing lead compounds as well as leaded
petrol use from 1931 to 1972, (De Vleeschouwer et al., 2007, Headley, 1996, Marx et al., 2010 and
Olid et al., 2010) which has been suggested contributes up to 75% of atmospheric lead (De

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Vleeschouwer et al., 2007). It has also been pointed out that because lead has a natural radionuclide
there is continuous fallout (Parry et al., 2013).
The use of SCPs for atmospheric pollution indication has only occurred recently, the first uses of it
were in lakes, purely for changes in atmospheric data (Rose et al., 1999). The majority of work they
have been included in is lakes, only until early in the previous decade where they applied in peats
(Yang et al., 2001). They have also been used as a dating method (Parry et al., 2013). They have not
been used in published work alongside magnetic minerals and heavy metals. There has been a
suggestion that unless there is bioturbation they are immobile (Yang et al., 2001), and as such they
have been used to date sediments from hard features (Yang et al., 2001). Patterns in SCP distribution
have been shown to have strong correlations with other pollutants, such as lead and polycyclic
aromatic hydrocarbons (Nagafuchi et al., 2009). They have to be counted under a microscope after
digesting the organic matter in the sample.
Magnetic mineral measurements are useful to complete on samples because they are non-
destructive, little pre-treatment is required and they pick up much lower quantities than other
methods (Oldfield et al., 2015, Olid et al., 2010). Magnetics cannot provide data that distinguishes
the amount of haematite from magnetite (Oldfield, 2015), but there is a suggestion that haematite is
more resistant to dissolution than magnetite (Oldfield, 2015). A full suite of magnetic mineral
measurements include susceptibility, ARM (Anhysteretic Remanent Magnetization), SIRM (Saturated
Isothermal Remanent Magnetism) and reverse field ratios. SIRM measures total magnetic mineral
concentrations, because magnetite is more magnetic than haematite the majority of what is picked
up is magnetite, this means that it is a proxy measurement (Oldfield et al., 2015). Magnetic mineral
studies have evolved fairly rapidly over the past 40 years, the original studies used them alongside
other variables, such as pollen (Richardson, 1986), as the time it was not considered that these
environmental archives may not remain intact, it was in fact assumed that they presented a
complete and reliable record. Williams (1992) suggested that magnetic minerals dissolved during

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decomposition of organic matter, this was the first time that the idea that this archive may not
present a reliable record was presented. Since then there has been development of this theory,
Rothwell and Lindsay (2007) investigated the difference within the micro-topography of a bog. They
concluded that there was a difference in dissolution within different topographic features. The two
theories put forward were: the differing abilities of vegetation to capture particulates and if the
retention of minerals if affected once they have entered the peat, but both theories are ultimately
controlled by the water table (Rothwell and Lindsay, 2007). Post depositional changes are diagenetic
processes, they make both dating and analysis inaccurate (Rothwell and Lindsay, 2007). Dissolution
is affected by the water table, the acrotelm is the upper layers of peat where the environment is
subject to oxidation and acidity changes, the catoelm, lower layers of peat, are more stable as they
are more likely to remain submerged, they also have a much lower redox potential (Martı́nez
Cortizas et al., 2002, Hutchinson and Armitage, 2005). Past climate can also affect the reliability of
the record as drier periods will oxidise some minerals and wetter periods will have more dissolution,
if the peat has been subjected to anthropogenic draining it has the same effect (Rothwell and
Lindsay, 2007). The state a mineral is in is dependent on the rate of growth and decay in peat, which
is once again ultimately controlled by the water table (Rothwell and Lindsay, 2007). It has also been
suggested that haematite is more likely to survive longer than magnetite because it is an original
mineral from the coal; magnetite forms the outer ring of the particulates (Oldfield et al., 2015).
Burning can also affect the record, although it can be a good method of heather management the
heat energy can magnify particulates (Hutchinson and Armitage, 2005). Burning is the second
biggest cause of degrading moorland, unless a suitable management strategy is in place (Hutchinson
and Armitage, 2005). Burning can also enhance the magnetic properties of minerals and can be used
as hard features for dating (Hutchinson and Armitage, 2005), burning above 200˚C in organic matter
enhances the magnetic properties because it can cause non-ferrimagnetic minerals to convert to
ferromagnetic minerals (Thompson and Oldfield, 1986).

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Peat is good at preserving lead, copper, nickel and zinc (De Vleeschouwer et al., 2007). Lead has
been shown to have the highest concentrations of all heavy metals, with much higher
concentrations nearer the surface, but it has also been found at deeper depths (De Vleeschouwer et
al., 2007, Martı́nez Cortizas et al., 2002). Lead take off in a peat profile is roughly dated at 1800
(Hutchinson and Armitage, 2005). There is some discussion about how mobile it is; Rothwell (2010)
found that it was the least mobile of the heavy metals, whereas Damman (1978) found it was the
most mobile element, it was suggested that the mobility was due to sulphur deposits and dissolved
organic matter. Lead profiles have been found to differ across the same bog (Olid et al., 2010). Yang
et al. (2001) and Rothwell and Lindsay (2007) both found that lead and zinc have similar profiles in
peat, including having peaks at similar depths. However Olid et al., (2010) found that zinc and copper
had similar profiles with peaks near the surface. Chromium and nickel have been found to have
similar profiles but they peaked at further depths in the peat, than lead and zinc (Hutchinson and
Armitage, 2009). Any metals which have a similar profile are likely to have a similar source
(Hutchinson and Armitage 2009). Yang et al., (2001) found that cadmium had a different profile to
the other metals and suggested that this may because it was more mobile than other metals. Marx
et al., (2010) found that Cobalt had a different pattern than the other metals. Many studies have
found that there were greater amounts of heavy metals nearer the surface (Yang et al., 2001,
Hutchinson and Armitage, 2009 and Headley, 1996). Hutchinson and Armitage (2009) found that
heavy metals increased above 1.5m, and Yang et al., (2001) suggested that relatively stable low
traces of metals in lower layers could be considered as background levels. Wetter peat causes
dissolution and mobility to become less predictable (Parry et al., 2013). It is widely accepted that
sulphur levels affect metal movement in peat (Martı́nez Cortizas et al., 2002, Yang et al., 2001.)
When there is a low redox potential (Eh) there is an increase in S2-
, which has a strong affinity to
metals (Yang et al., 2001). Deeper peat has less chance of being exposed to air and remains
waterlogged so it has a lower Eh, this allows the formation of metal sulphides which are insoluble
(Yang et al., 2001), it therefore has a fixing effect (Martı́nez Cortizas et al., 2002). However, iron and

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manganese are more soluble under reducing conditions which allows for redistribution and changes
to the concentration of metals (Yang et al., 2001).
The spatial distribution of pollutants is dependent on the spatial distribution of the emitters
(Thompson and Oldfield, 1986), the smaller the particle the further it can travel (Rose et al., 1999).
Atmospheric movement can transport particulates far from the source (Yang et al., 2001). A study on
European lakes showed that the highest pollutant levels were in central Europe but there was also a
definite regional influence on some of the lakes situated near industry (Rose et al., 1999). There is a
European monitoring and evaluation program in place to calculate and monitor airborne particulates
and their main pathways through Europe (Rose et al., 1999). In the UK the spatial distribution of
where the earliest initial pollution is found differs, it is influenced by when the local sources began
and by the proximity of the peat to the industrial development (Oldfield, 2015). SCPs are deposited
through precipitation, the higher the precipitation levels the more SCPs are found (Parry et al.,
2013). SCPs have been found up to 70-100km away from their source and have also been used to
identify their source (Nagafuchi et al., 2009). In high resolution studies SCPs can be linked to
economy growth, for example when oil overtakes coal as a main fuel there is a decrease in SCPs, and
when there is an oil crisis there is a resulting increase in coal use there is an increase in SCPs
(Nagafuchi et al., 2009).
It is generally accepted that when environmental archives are examined the analysis is more
accurate when it is dated (Parry et al., 2003, Oldfield et al., 2015, Oldfield, 2015). There are different
methods for different timescales, for example C14
is more appropriate for Holocene change, rather
than change in the Anthropocene (Parry et al., 2013). Dating techniques must be appropriate to the
archive that is being examined, and it must also be accurate and precise for the time period in which
the data is required from (Oldfield, 2015). Therefore, the best dating method for recent
environmental change is 210
Pb dating, this is because it has a half-life of 22.3 years, making it most
appropriate for the past 200 years (Bao et al., 2010, Oldfield, 2015). Because it is the most

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appropriate method it has been used frequently (Olid et al., 2010, Oldfield et al., 2015, De
Vleeschouwer et al., 2007, Nagafuchi et al., 2009, Marx et al., 2010). The other two radionuclides
that are mainly used are Cs137
(Oldfield et al., 2015, Rose et al., 1999, Oldfield, 2015, Nagafuchi et al.,
2009) and Am241
(Oldfield et al., 2015, Rose et al., 1999). However, it is best if more than one
radionuclide is used for dating as there are problems with each radionuclide (Parry et al., 2013). For
example Cs137
has an affinity to clay, because peat has no clay in it the radionuclide has nothing to
bind to (Parry et al., 2013). Am241
is considered the best radionuclide because it is less mobile than
other nuclides, however, it is found in much lower quantities than the others, and sometimes it is
not possible to find any in a sample (Parry et al., 2013). There are other methods of dating that do
not include radionuclides include moss increment dating and pollen analysis (Oldfield et al., 2015). It
is also possible to link data found from an archive to historical records (Oldfield et al., 1981).
1.1 Aims and Objectives
The aim of this investigation is to investigate the recent pollution records held in Forest of Bowland
peat cores. The research questions posed are whether there is a distance decay trend away from the
area of Greater Manchester, and if there is not whether the record had been altered due to
diagenetic processes. In order to do this the variables that will be considered and analysed are
magnetic mineral measurements, heavy metals and Spheroidal Carbonaceous Particles (SCPs).
Comparing SCPs and magnetic minerals has never been completed in any published work. The works
completed in the Forest of Bowland previously are on peat erosion (Mackay and Tallis, 1996) and
vegetation change in the Holocene (Mackay and Tallis, 1994). No atmospheric pollution studies have
been carried out on peat in this area.

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2.0 Methods
2.1 Location
Figure 1 shows the location of the Forest of Bowland Area of Outstanding Natural Beauty (AONB). It
is in the North West of England and covers 803km2
(312 square miles), it spans across Lancashire and
Yorkshire, 89% of the total area is in Lancashire (Lancashire County Council, 2015a). When it was
given protected status in 1964 it was protected under the National Parks and Access to Countryside
Act (1949), and then again in 2000 under the Countryside and Rights of Way Act (Lancashire County
Council, 2015a). To be granted these statuses an area has to have a historical or cultural impact,
contain unusual flora or fauna or exceptional scenery, the Forest of Bowland was awarded this
because of its landscapes and its beauty, AONBs only make up 18% of the land in England and Wales
so they are highly specialised areas (Lancashire County Council, 2015a). They aim to give the area
protection, as well as conserve the environment for future generations (Lancashire County Council,
2015a). 13% of the Forest of Bowland AONB has been designated SSSI (Lancashire County Council,
2015b), two of the sites chosen for this study were SSSI, those labelled in figure 2 as 1 and 2, at
Bleasdale and Abbeystead respectively. The gird reference for Bleasdale is SD587 484 and the grid
reference for Abbeystead is SD619 525. The third was taken on the moors in the North of the AONB
towards Ingleton, grid reference SD685 609. The fourth was in the South East on the top of Pendle
Hill, grid reference SD787 399. The sites were with increasing distance from Greater Manchester;
however, accessibility had to be taken into account alongside this requirement which is why they are
not linear sites. However where the sites are still allows a distance decay analysis from Greater
Manchester.

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Figure1:theForestofBowlandAONBisintheNorthWestofEngland,NorthofGreaterManchesterandtotheEastofLancaster
andMorecambeBay(Digimap,2015a)

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Figure2:ShowsthelocationsofthecoresintheForestofBowland,AtBentham,Abbeystead,BleasdaleandPendleHill(Digimap,
2015b
1
2
3

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2.2 Field Methods
In atmospheric pollution record studies field methods differ because of the varying dimensions of
each study. For example Rothwell and Lindsay (2007) had 3 parallel transects which were 450m long
and 250m apart, they took 24 cores from one peat bog, but they were examining the effect of
microtopography and the effect of dissolution in different areas. For this study one core was taken
from each location, the core was taken from a hummock or a dry patch where there was no standing
water, peat gullies and eroded patches were also avoided, in response to the findings of Rothwell
and Lindsay, (2007). The depth of the core is dependent on the rate of accumulation and the
timescale to which the study is focused on, Hutchinson and Armitage (2009) took a 4.3m core,
however, they were looking at environmental change as well as pollution. For atmospheric pollution
alone it is common for 30cm to be taken, (Parry et al., 2013, Nagafuchi et al., 2009) this is the depth
to which these cores have been taken. There are different methods of retrieving the core from the
ground, Russian corers are commonly used (Marx et al., 2010) but these are usually used when
deeper cores are required. For this study a PVC tube is inserted into the peat by hand and dug out,
similar to the method adopted by Yang et al. (2001) as shown in plate 1. Once the core has been
removed it is wrapped up for transport and stored vertically.
Plate 1: the PVC tube inserted into the peat at Abbeystead, once pushed in completely the core is
dug out and the hole filled in. (Photograph: Elanor Brown, June 2015)

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2.3 Laboratory Methods
Once in the lab the core has to be sliced into appropriate segments, although Bao et al. (2010) cut up
the core onsite, this would reduce any movement in the core post extraction but is more time
consuming and difficult in hard to reach areas. The interval size depends on the detail and timescale
of the study, environmental change studies usually have longer intervals, Hutchinson and Armitage
(2009) used 2cm. For pollution records since the Industrial Revolution it is more appropriate to cut
smaller segments to increase the detail, it is common to cut 1cm slices (Yang et al., 2001, Parry et al.,
2013), however some studies cut up the core into even finer detail, every 2-5mm (Marx et al., 2010).
In this study the core is separated into 1cm slices, as shown in plate 2.
Plate 2: the peat core once removed from the PVC tube, segmented into 1cm slices, prior to cutting
(Photograph: Elanor Brown, June 2015)

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Drying the samples out varies from study to study, some studies dry for a short time at a high
temperature (Rothwell et al., 2005, Headley, 1996) for example at 80˚C for 48 hours (Headley, 1996).
However, this may not make the samples completely dry, so the samples in this study were oven
dried at 40˚C for as long as it took to make them dry, this temperature was used in order to prevent
the magnetic minerals being affected (Thompson and Oldfield, 1986). Once the samples were dry
they had to be ground up for the magnetics analysis. This has to be done by hand, although
machines have been used (De Vleeschouwer et al., 2007). However, because they use metal it is not
advisable when the sample is undergoing magnetic mineral analysis. Once this has been completed
the samples underwent the main analysis.
Other works that studied atmospheric pollution records in peat which used one or more of the other
lab techniques mentioned above also looked at other variables. For example bulk density (Bao et al.,
2010, Yang et al., 2001 and Nagafuchi et al., 2009), water content (Yang et al., Rothwell and Lindsay,
2007), and organic matter content, via loss on ignition (Bao et al., 2010, Nagafuchi et al. 2009, and
Yang et al., 2001). These variables add extra dimensions to the studies that allowed the authors to
add different perspectives, for example Rothwell and Lindsay (2007) used a topographic wetness
index, which indicates how likely an area is to be saturated alongside LiDAR to compare wetness
with topography. However non-of the studies combined heavy metals, SCPs and Magnetic Mineral
measurements. Bulk density is measured in this study by weighing the dried slices of peat and
multiplying by the slice volume, it has been suggested that an increase in bulk density may cause a
concentration of metals (Hutchinson and Armitage, 2005). Dry bulk densities have been investigated
with varying results. On the one hand dry bulk density has been found to increase with depth, (Bao
et al., 2010, Hutchinson and Armitage, 2009) because there is a higher mineral content nearer the
base, when a peat is not fully ombrotrophic it is suboptimal (Hutchinson and Armitage, 2009).
However, Parry et al. (2013) found that bulk density varies with depth and there were no links to
depth or water content.

P a g e | 22
2.31 XRF
The main two methods of finding metal concentrations in peat archives are X-ray Fluorescence (XRF)
and Atomic Adsorption Spectroscopy (AAS). XRF is for dry samples and AAS is wet chemistry. Some
studies have used XRF (Olid et al., 2010, De Vleeschouwer et al., 2007) and the main advantages of
XRF are that it is quick and simple to complete, the analysis is non-destructive, allowing for more
tests to be carried out afterwards, and there is very little preparation of the sample required
(DeRamos King, 2014). The main disadvantage is that it is not as accurate as AAS (DeRamos King,
2014). AAS, although more accurate than XRF, is a destructive test, which requires lots of
preparation of the sample and more time (DeRamos King, 2014). Some studies have used AAS
instead (Yang et al., 2001, Bao et al., 2010 and Headley, 1996). The sample has to be digested in
order for AAS to be used, one method of doing this is to boil the sample in HNO3 for an hour, to
remove the organic material, and it is then mixed with distilled water and filtered (Yang et al., 2001).
In this study XRF has been used for heavy metal analysis.
2.32 SCP Preparation
The original method for SCP preparation is outlined in Rose et al., (1999). To begin with the sample is
boiled in HNO3 to remove organic matter, followed by HF to remove siliceous material and HCl to
remove bicarbonates and carbonates (Rose et al., 1999, Nagafuchi et al., 2009). However, the
method used in this study is the one completed by Parry et al., (2013). The sample was weighed and
boiled in HNO3 for an hour and a half, and then centrifuged, boiled again; finally the sample is
repeatedly washed. Once this has finished a lycopodium tablet is added and glycerol which eases
slide use. The units for SCPs are particle numbers per gram of dry mass sediment (gDM-1
) (Nagafuchi
et al., 2009). Parry et al. (2013) suggest that to compare SCPs from different cores they must be
converted into inventories, in this study the SCP concentration is multiplied by the slice weight to
normalise the samples.

P a g e | 23
2.33 Magnetic Mineral Measurements
Magnetic mineral measurements can be used to identify sediment sources, but they can also be
used to identify Inorganic Ash Spheres (IAS) (Nagafuchi et al., 2009). The main advantages of using
magnetic mineral measurements are that they are rapid and non-destructive (Hutchinson and
Armitage, 2005). A full suite of magnetic mineral measurements contains data on susceptibility,
ARM, SIRM and reverse field ratios; they produce measurements on the grain size and type, as well
as the quantity in a sample (Hutchinson and Armitage, 2005). In more recent studies magnetic
susceptibility in peat has not been used because the results are very low and which yields little
helpful insight (Hutchinson and Armitage, 2009). The parameters used in this study are shown in
table 1; they include Saturation Isothermal Remanent Magnetisation (SIRM) and the associated
reverse field ratios. Anhysteretic Remanent Magnetisation (ARM) has also been measured but used
in conjunction with SIRM.
High values Low Values
SIRM Increase in the quantity of
magnetic minerals as a whole
Decrease in the quantity of
magnetic minerals
Reverse field ratios Soft magnetic behaviour,
indicative of coarse grained
ferrimagnetic minerals e.g.
magnetite
Hard magnetic behaviour,
which either indicates fine
ferrimagnetic or a significant
antiferromagnetic aspect
SIRM/ARM Coarse grained ferrimagnetic Fine grained ferrimagnetic
Table 1: the varying magnetic parameters used in this study and their meanings (Adapted from Jones
et al., 2014 and Thompson and Oldfield, 1986).
SIRM is when a sample is put in a strong magnetic field, 1 tesla, and saturated with magnetism, this
is completed using the Molspin Pulse Magnetiser, and the remanence retained is measured in the
Molspin magnetometer (Edge Hill University, date unknown). SIRM is temperature dependant, and
should be completed at room temperature; it is also mass specific; the units are Am2
kg-1
(Edge Hill
University, date unknown). SIRM indicates the concentration of magnetic minerals (Jones et al.,
2014). The reverse field ratios that are a result of systematically demagnetising the saturated

P a g e | 24
sample, the demagnetised sample value is divided by the SIRM which produces a ratio of change;
the parameters used in this study are IRM-20mT/SIRM; IRM-40mT/SIRM; IRM-100mT/SIRM; and IRM-
300mT/SIRM. When these values are more negative it is indicative of a hard magnetic behaviour,
(material that is not easily demagnetised) and suggests the presence of either fine ferrimagnetic
minerals and normally together with a significant antiferromagnetic component. ARM was
completed for these samples, and SIRM/ARM was used, this is an indicator of magnetic grain size,
the higher the value, the larger the magnetic mineral grain size (Edge Hill University, date unknown).
Hutchinson and Armitage (2005) completed a full suite of magnetics; they used a Bartington MS2
susceptibility system to measure susceptibility, a Molspin AF demagnetiser to create an ARM signal,
and Molspin pulse discharge magnetiser to create a SIRM signal. ARM and SIRM measurements are
recorded using a Molspin fluxgate magnetometer (Hutchinson and Armitage, 2009).

P a g e | 25
3.0 Results
3.1 Bleasdale - Core 1
3.11 Magnetics
Figure 3: SIRM and reverse field ratios (IRM-20mT/SIRM, IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-
300mT/SIRM) against depth (cm) for core 1 from Abbeystead
0.00
200.00
400.00
600.00
800.00
1000.00
1200.00
1400.00
1600.00
1800.00
2000.00
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
SIRM(Am2kg-1)
Depth (cm)

P a g e | 26
Figure 4: SIRM/ARM changes against depth (cm) for core 1
Figure 5: Bulk density changes (gcm-3
) against depth (cm) for core 1
3.12 XRF
Figure 6: Iron concentration in ppm against depth (cm) for core 1
0
2
4
6
8
10
12
0.00 1000.00 2000.00 3000.00 4000.00 5000.00
Depth(cm) SIRM/ARM
0
2
4
6
8
10
12
0 0.05 0.1 0.15 0.2 0.25
Depth(cm)
Bulk Density (gcm-3)
0
5
10
15
20
25
30
35
0 1000 2000 3000 4000 5000 6000
Depth(cm)
Fe concentration (ppm)

P a g e | 27
Figure 7: Copper concentration in ppm against depth (cm) in core 1
Figure 8: Zinc concentration in ppm against depth (cm) for core 1
Figure 9: Lead concentration in ppm against depth (cm) for core 1
0
5
10
15
20
25
30
35
0 5 10 15 20 25 30 35
Depth(cm) Cu Concentration (ppm)
0
5
10
15
20
25
30
35
0 50 100 150 200
Depth(cm)
Zn Concentration (ppm)
0
5
10
15
20
25
30
35
0 50 100 150 200 250 300
Depth(cm)
Pb Concentration (ppm)

P a g e | 28
Figure 10a: Correlation between SIRM (Am2
kg-1
) and iron concentration (ppm) for core 1
Figure 10b: Correlation between SIRM (Am2
kg-1
) and copper concentration (ppm) for core 1
Figure 10c: Correlation between SIRM (Am2
kg-1
) and zinc concentration (ppm) for core 1
0
1000
2000
3000
4000
5000
6000
0 500 1000 1500 2000
Fe(ppm)
SIRM (Am2kg-1)
0
5
10
15
20
25
30
35
0 500 1000 1500 2000
Cu(ppm)
SIRM (Am2kg-1)
0
20
40
60
80
100
120
140
160
180
200
0 500 1000 1500 2000
Zn(ppm)
SIRM (Am2kg-1)

P a g e | 29
Figure 10d: Correlation between SIRM (Am2
kg-1
) and lead concentration (ppm) for core 1
0
50
100
150
200
250
300
0 500 1000 1500 2000
Pb(ppm)
SIRM (Am2kg-1)

P a g e | 30
3.2 Abbeystead - Core 2
3.21 Magnetics
Figure 11: SIRM and Reverse Field Ratios IRM-20mT/SIRM, IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-
300mT/SIRM against depth (cm) for core 2, from Bleasdale
0.00
50.00
100.00
150.00
200.00
250.00
300.00
350.00
400.00
0 5 10 15 20 25 30 35
SIRM(Am2kg-1)
Depth (cm)

P a g e | 31
Figure 13: Bulk density (gcm-3
) changes against depth (cm) for core 2
3.22 XRF
0
1
2
3
4
5
6
7
0.00 1000.00 2000.00 3000.00 4000.00 5000.00
Depth(cm) SIRM/ARM
0
1
2
3
4
5
6
7
8
0 0.05 0.1 0.15 0.2 0.25
Depth(cm)
0
5
10
15
20
25
30
35
0 1000 2000 3000 4000 5000 6000
Depth(cm)
Fe Concentration (ppm)

P a g e | 32
Figure 15: Copper concentration in ppm, against depth (cm) for core 2
0
5
10
15
20
25
30
35
0 5 10 15 20 25 30 35
Depth(cm) Cu Concentration (ppm)
0
5
10
15
20
25
30
35
0 50 100 150 200
Depth(cm)
0
5
10
15
20
25
30
35
0 50 100 150 200 250 300 350
Depth(cm)
Pb Concentration (ppm)

P a g e | 33
kg-1
kg-1
kg-1
0
1000
2000
3000
4000
5000
6000
0 100 200 300 400
Fe(ppm)
SIRM (Am2kg-1)
0
5
10
15
20
25
30
35
0 100 200 300 400
Cu(ppm)
SIRM (Am2kg-1)
0
50
100
150
200
0 100 200 300 400
Zn(ppm)
SIRM (Am2kg-1)

P a g e | 34
kg-1
0
50
100
150
200
250
300
350
0 100 200 300 400
Pb(ppm)
SIRM (Am2kg-1)

P a g e | 35
3.3 Bentham - Core 3
3.31 Magnetics
Figure 19: SIRM and Reverse Field Ratios (IRM-20mT/SIRM, IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-
300mT/SIRM)against depth (cm) for core 3, Bentham
0.00
1000.00
2000.00
3000.00
4000.00
5000.00
6000.00
7000.00
8000.00
9000.00
0 5 10 15 20 25 30 35
SIRM(Am2kg-1)
Depth (cm)

P a g e | 36
3.32 SCPs
Figure 22: SCP concentration in gDM-1
against depth (cm) for core 3
0
2
4
6
8
10
12
14
16
18
0 500 1000 1500 2000 2500 3000
Depth(cm) SIRM/ARM
0
2
4
6
8
10
12
14
16
18
0 0.1 0.2 0.3 0.4 0.5
Depth(cm)
0
5
10
15
20
25
0 50000 100000 150000 200000
Depth(cm)
SCP concentration (gDM-1)

P a g e | 37
3.33 XRF
Figure 24: Copper concentration in ppm against depth (cm) for core 3
0
5
10
15
20
25
30
35
0 5000 10000 15000 20000 25000
Depth(cm)
Fe concentration (ppm)
0
5
10
15
20
25
30
35
0 20 40 60 80 100 120
Depth(cm)
Cu Concentration (ppm)
0
5
10
15
20
25
30
35
0 20 40 60 80 100 120 140
Depth(cm)
Zn concentration (ppm)

P a g e | 38
kg-1
kg-1
0
5
10
15
20
25
30
35
0 100 200 300 400 500 600 700
Depth(cm) Pb Concentration (ppm)
0
5000
10000
15000
20000
25000
0 2000 4000 6000 8000 10000
Fe(ppm)
SIRM (Am2kg-1)
0
20
40
60
80
100
120
0 2000 4000 6000 8000 10000
Cu(ppm)
SIRM (Am2kg-1)

P a g e | 39
kg-1
kg-1
0
20
40
60
80
100
120
140
0 2000 4000 6000 8000 10000
Zn(ppm)
SIRM (Am2kg-1)
0
100
200
300
400
500
600
700
0 2000 4000 6000 8000 10000
Pb(ppm)
SIRM (Am2kg-1)

P a g e | 40
3.4 Pendle Hill - Core 4
3.41 Magnetics
Figure 28: SIRM and Reverse Field Ratios (IRM-20mT/SIRM, IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-
300mT/SIRM) for Core 4 (Pendle)
0.00
5000.00
10000.00
15000.00
20000.00
25000.00
0 5 10 15 20 25 30 35
SIRM(Am2kg-1)
Depth (cm)

P a g e | 41
Figure 29: SIRM/ARM changes against depth (cm) core 4
3.42 SCPs
Figure 31: SCP concentration in gDM-1
against depth (cm) for core 4
0
2
4
6
8
10
12
14
16
18
20
0.00 200.00 400.00 600.00 800.00 1000.00
Depth(cm) SIRM/ARM
0
2
4
6
8
10
12
14
16
18
0 0.05 0.1 0.15 0.2 0.25 0.3
Depth(cm)
0
5
10
15
20
25
0 50000 100000 150000 200000
Depth(cm)
SCP concentration (gDM-1)

P a g e | 42
3.43 XRF
Figure 33: Copper concentration in ppm against depth (cm) for core 4
0
5
10
15
20
25
30
35
0 10000 20000 30000 40000
Depth(cm)
Fe Concentration (ppm)
0
5
10
15
20
25
30
35
0 50 100 150 200 250
Depth(cm)
Cu Concentration (ppm)
0
5
10
15
20
25
30
35
0 50 100 150 200 250
Depth(cm)

P a g e | 43
kg-1
kg-1
0
5
10
15
20
25
30
35
0 200 400 600 800 1000 1200 1400
Dpeth(cm) Pb Concentration (ppm)
0
5000
10000
15000
20000
25000
30000
35000
40000
0 5000 10000 15000 20000 25000
Fe(ppm)
SIRM (Am2kg-1)
0
50
100
150
200
250
0 5000 10000 15000 20000 25000
Cu(ppm)
SIRM (Am2kg-1)

P a g e | 44
kg-1
kg-1
0
50
100
150
200
250
0 5000 10000 15000 20000 25000
Zn(ppm)
SIRM (Am2kg-1)
0
200
400
600
800
1000
1200
1400
0 5000 10000 15000 20000 25000
Pb(ppm)
SIRM (Am2kg-1)

P a g e | 45
4.0 Results Description
4.1 Bleasdale - Core 1
4.111 SIRM and Reverse Field Ratios
Figure 3 shows SIRM and the reverse field ratios for core 1. The SIRM shows that there are two
peaks in this core, one at 5.5cm and another at 3.5cm. The initial increase in SIRM occurs at 8.5cm;
prior to this depth the values are generally low. Between 8.5cm and 5.5cm there is a steep rise, this
is the first peak, the SIRM at 5.5cm is 853.26Am2
kg-1
. There is then a sharp drop between here and
4.5cm where the SIRM is 308.05Am2
kg-1
. After 4.5cm the second peak occurs, there is a very sharp
increase, so at 3.5cm the SIRM is 1798.78Am2
kg-1
. The SIRM falls away after this, to 2.5cm where it is
908.25Am2
kg-1
, between here and 0.5cm there is a small increase to 1025.01Am2
kg-1
. The reverse
field ratios for core 1 show that the values for IRM-20mT/SIRM are between 7 and 29%, the IRM-
40mT/SIRM values are between 27 and 44%, the IRM-100mT/SIRM values are between 55 and 86% and
the IRM-300mT/SIRM values are between 89 and 110%. At 7.5cm, all four of the reverse field ratios
have a peak. There is a drop in the IRM-100mT/SIRM and IRM-300mT/SIRM ratios at 9.5cm. At 12.5cm
there is a slight peak for the IRM-20mT/SIRM and IRM-40mT/SIRM, but for the IRM-100mT/SIRM and IRM-
300mT/SIRM there is a slight trough. At 13.5cm the ratio for the IRM-20mT/SIRM and IRM-40mT/SIRM
drops, but increases for the IRM-100mT/SIRM IRM-300mT/SIRM ratios.
4.112 SIRM/ARM Ratio
The SIRM/ARM changes for core 1 are shown in figure 4. There are three peaks present, firstly at
8.5cm; this is a small peak, where the ratio is 387.48. The second peak is at 4.5cm, here the ratio is
3222.47. There is then a decline and this is followed by another increase, into another peak at
1.5cm, where the maximum ratio occurs, 3895.18.

P a g e | 46
4.12 Bulk Density
The Bulk density changes for core 1 are shown in figure 5. There are three peaks found, the first is at
10.5cm, the density here is 0.15gcm-3
, above this there is a decrease in density, followed by another
peak at 8.5cm, where the density is 0.16gcm-3
. The second peak is at 6.5cm where the density is
0.21gcm-3
; the highest density. Between here and the surface the density decreases to 0.04gcm-3
.
4.13 Heavy Metals
4.131 Iron
The iron concentration for core 1 is shown in figure 6. Iron has the highest abundance of all the
heavy metals. On the whole it decreases with depth although there is an increase in concentration
around 20cm. Between 29.5cm and 24.5cm there is a slight decrease from 1491ppm to 1036ppm.
There is then an increase in concentration to 18.5cm where the concentration is 3460ppm. The
concentration then drops so at 10.5cm the concentration is 932ppm, this is then followed by an
increase in concentration, so there is a peak at 5.5cm, the concentration here is 2943ppm. There is
another peak at 3.5cm, where the concentration is 4493ppm; this is followed by another peak at
1.5cm, where the maximum concentration, 4965ppm, occurs.
4.132 Copper
Core 1 copper concentration is shown in figure 7. There are only low concentrations present in this
core. There is none found until 3.5cm, where there is a sharp increase from the previous centimetre
to 18ppm. There is another peak at 1.5cm, where there is 32ppm, this is the maximum
concentration found. Between here and 0.5cm there is a decrease to 15ppm.
4.133 Zinc
The zinc concentration for core 1 decreases with depth fairly steadily (figure 8). There is none
present until 23.5cm, the concentration here is 13ppm. From here to 12.5cm there is a steady
increase, but the concentration remains fairly low, below 72ppm. Between 12.5cm and 6.5cm, there

P a g e | 47
is a sharp increase to 175ppm. There is then a peak at 4.5cm and another peak at 1.5cm, the
concentrations are 174ppm and 181ppm respectively.
4.134 Lead
On the whole lead concentrations decrease with depth (Figure 9); it is also the second most
abundant metal. From 29.5cm to 12.5cm, there is an increase from 30ppm to 117ppm. Between
12.5cm and 10.5cm there is a small drop to 93ppm. From 10.5cm to the surface the concentration
has a series of peaks; the first is at 5.5cm, where the concentration is 129ppm. There is another peak
at 3.5cm; here the concentration is 180ppm. At 1.5cm the maximum concentration occurs, 255ppm.
Figure 11 shows the SIRM and reverse field ratios for core 2. There are generally very low SIRM
values until 15.5cm, where initial increase occurs. There are three peaks after take-off; the first is at
5.5cm, where the SIRM is 93.77Am2
kg-1
. The second is at 3.5cm, where the SIRM is 195.5Am2
kg-1
,
and the third is at 0.5cm, 377.44Am2
kg-1
, this is where the maximum SIRM occurs. The reverse field
ratios in core 2 show that IRM-100mT/SIRM and IRM-300mT/SIRM mirror each other in changes, except
for the IRM-300mT/SIRM values being larger. IRM-300mT/SIRM values are between 84 and 105%, IRM-
100mT/SIRM values are between 65 and 90%, the values for IRM-40mT/SIRM are between 20 and 44%,
and finally the values for IRM-20mT/SIRM are between 8 and 15%. IRM-40mT/SIRM, IRM-100mT/SIRM and
IRM-300mT/SIRM peaks between 6.5 and 11.5cm, and another between 12.5 and 18.5cm. There is a
trough reflected in all four of the reverse field ratios at 18.5cm. There is a peak at 19.9cm which is
only reflected in IRM-20mT/SIRM and IRM-40mT/SIRM. At 27.5cm there is a peak in IRM-40mT/SIRM, IRM-
100mT/SIRM and IRM-300mT/SIRM, but there is a trough in the IRM-20mT/SIRM.

P a g e | 48
4.212 SIRM/ARM
The SIRM/ARM changes for core 2 are shown in figure 12. There are two peaks in this core, the first
is at 5.5cm, the concentration is 3328.60. After this peak there is a decrease to 1709.48 at 4.5cm,
followed by another increase and peak at 0.5cm, the ratio here is 4223.66.
4.22 Bulk Density
The bulk density changes show that the highest density is at 7.5cm, 0.2gcm-3
(figure 13). Between
7.5cm and 3.5cm there is a steady decrease to 0.08gcm-3
,after which it increases, at 0.5cm the
density is 0.16gcm-3
.
4.23 Heavy Metals
4.231 Iron
Figure 14 shows the concentration of iron against depth for core 2; iron has the highest abundance
of all metals in this core. There appear to be three main peaks. The first is at 21.5cm, this is the
smallest peak, and the concentration is 2971ppm. There is then a small decrease followed by a sharp
increase to the second peak, at 12.5cm, where the concentration reaches its maximum, 5344ppm.
There is then a sharp decline to 7.5cm, before it increases again to another peak at 0.5cm here the
concentration is 4205ppm.
4.232 Copper
Figure 15 shows that there are low concentrations of copper in core 2. There is none present until
5.5cm, where the concentration is 10ppm, there is then an increase in concentration to 22ppm at
2.5cm. This is followed by a decrease in concentration to 11ppm at 1.5cm; there is then an increase
to the maximum concentration, 30ppm, at 0.5cm.
4.233 Zinc
The changes in zinc concentrations for core 2 are shown in figure 16. The overall trend is a decrease
with depth, except at 11.5cm, where there is an inrease. Between 29.5cm and 11.5cm there is a

P a g e | 49
gentle increase in concentration from 29ppm to 161ppm. There is a small decrease between 11.5cm
and 7.5cm, to 119ppm, from here to the surface there is a small increase to 139ppm.
4.234 Lead
Figure 17 shows the concentration of lead in core 2 against depth. The general trend shows a
decrease with depth, in varying rates. Between 29.5cm and 10.5cm there is very little change,
36ppm to 70ppm. From 10.5cm to 2.5cm the concentration increases to 249ppm. There is a small
decrease before there is another increase, the maximum concentration is at the surface, 289ppm.
Figure 19 shows the SIRM and reverse field ratios for core 3. The first depth at which the
concentration significantly increases seems to occur at 16.5cm; below this depth the SIRM is
generally low. The first peak is at 13.5cm, where the concentration is 2740.42Am2
kg-1
. The next peak
is at 10.5cm, this is where the maximum concentration occurs, 7812.63Am2
kg-1
. There is then a
sharp decrease followed by another peak at 8.5cm, 3208.90Am2
kg-1
, and the fourth peak is at 4.5cm,
here the concentration is 3438.34Am2
kg-1
. There is another peak at 2.5cm, where the concentration
is 3538.91Am2
kg-1
. The final peak is at 0.5cm, and the concentration increases to 6128.90Am2
kg-1
.
The reverse field ratios show very few changes with depth; there are no particular peaks or troughs.
The IRM-20mT/SIRM ratio is between 10 and 15%, the ratio for IRM-40mT/SIRM is between 30 and 40%,
between 69 and 77%for IRM-100mT/SIRM, and for IRM-300mT/SIRM the ratio is between 85 and 95%.
4.312 SIRM/ARM
The SIRM/ARM changes show that there is a peak at 16.5cm, the ratio here is 2746.83 (figure 20).
There is a small peak at 12.5cm, the ratio is 1968.77, and this is followed by a sharp decrease, to

P a g e | 50
423.97 at 11.5cm. There are three more peaks, one at 10.5cm, one at 7.5cm and finally one at
2.5cm, where the ratios are 2011.75, 2017.73 and 2239.93 respectively.
4.32 Bulk Density
The bulk density changes for core 3 are shown in figure 21. There are four peaks, the first is at
15.5cm, and the density here is 0.18gcm-3
. The second peak is at 13.5cm, where the concentration is
0.19gcm-3
, the third peak is of a similar density at 11.5cm, and the concentration here is 0.2gcm-3
.
The third peak is much greater than the others, the density is 0.39gcm-3
at 7.5cm, and from here to
the surface there density decreases to 0.06gcm-3
at 0.5cm.
4.33 SCP Concentration
There seem to be two peaks in SCP concentration in core 3 (Figure 22). There are three peaks in SCP
concentrations; the first is at 23.5cm, where the concentration is 60956.51gDM-1
. This is then a small
decrease to 21.5cm, where the concentration is 29939.52gDM-1
. This is followed by another peak at
19.5cm, where the concentration is 107251.08gDM-1
, and then the third peak is at 12.5cm where the
maximum concentration occurs, 154183.70gDM-1
.
4.34 Heavy Metals
4.341 Iron
The iron concentration for core 3 is shown in figure 23. The first peak is at 23.5cm, where the
concentration is 17804ppm, this is the second highest concentration of iron for this core. There is
then a sharp drop to 2892ppm at 16.5cm. The second peak is at 9.5cm, this is where the maximum
concentration is, 21327ppm. The three remaining peaks are at 4.5cm, 2.5cm and 0.5cm, these are all
of a similar concentration, 11369ppm, 13268ppm and 12440ppm respectively.
4.342 Copper
The copper concentrations for core 3 are shown in figure 24. There are five peaks in concentration.
The first at 23.5cm is the smallest, 13ppm. The second is the highest peak, and contains the

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maximum concentration, 98ppm. This is followed by a sharp decrease to 35ppm at 6.5cm. There is
then another peak at 5.5cm, followed by another two at 2.5cm and 0.5cm, the concentrations for
these peaks varies little, between 46 and 48ppm.
4.343 Zinc
Figure 25 shows the changes in zinc concentration in core 3. There are six peaks of varying
concentrations present in this core. The first is at 24.5cm, where the concentration is 115ppm; there
is a small decrease to 88ppm at 23.5cm. The second peak is at 18.5cm and the concentration is
128ppm, this is the maximum concentration for this core. The next peak is at 10.5cm, where the
concentration increases to 104ppm. There is a small peak at 5.5cm, the concentration here is
78ppm, and this is then followed by another peak at 2.5cm and one at 0.5cm, the concentrations of
which are 68ppm and 73ppm respectively.
4.344 Lead
The lead concentration for core 3 is shown in figure 26. There is a gentle increase between 29.5cm
and 16.5cm, from 20ppm to 127ppm. From 16.5cm to 11.5cm there is a sharp increase to the
maximum concentration 661ppm. Between 11.5cm and 6.5cm there is a sharp decrease to 127ppm.
There are subsequently three peaks, one at 5.5cm, 78ppm, another at 2.5cm, 68ppm and finally one
at 0.5cm where the concentration is 73ppm.
Figure 28 shows the SIRM and reverse field ratios for core 4. SIRM initially increases at 16.5cm;
below this depth it is generally low. There are three peaks in SIRM for this core. The first is at
14.5cm; here the SIRM is 2632.78Am2
kg-1
, the second peak is at 12.5cm, the SIRM is 2056.53Am2
kg-1
.
The next peak is the largest, and contains the maximum SIRM, 20261.00Am2
kg-1
; the depth at which

P a g e | 52
this occurs is 10.5cm. There is then a sharp decrease between here and the surface. The ratio for
IRM-20mT/SIRM is between 8 and 19%, for IRM-40mT/SIRM the ratio is between 26 and 44%, the ratio
for IRM-100mT/SIRM is between 55 and 81%, and for IRM-300mT/SIRM the ratio is between 78 and 97%.
There is a trough present between 11.5cm and 15.5cm which is shown in all four reverse ratios.
There is also a peak reflected in the IRM-20mT/SIRM, IRM-40mT/SIRM and IRM-100mT/SIRM ratios at
20.5cm. At 19.5cm and 22.5cm there is a small peak reflected in all four reverse ratios.
4.412 SIRM/ARM
There are four peaks of varying concentration for the SIRM/ARM in core 4 (figure 29). The first is at
17.5cm, where the ratio is 440.94. The next is at 13.5cm where the ratio is 235.85, there is then a
drop in the ratio, followed by another increase at 7.5cm, the ratio here is 589.52. This is followed by
a sharp decrease to 5.5cm; the next peak is at 4.5cm, where the ratio is 939.81. The ratio falls away
from this point to the surface.
4.42 Bulk Density
The changes in bulk density are shown in figure 30 for core 4. There are four peaks shown, the first is
at 15.5cm, where the density is 0.27gcm-3
, there is then a sharp decrease to 14.5cm, the density
here is 0.18gcm-3
. The next peak is at 12.5cm, the maximum density is here, and it is 0.28gcm-3
. The
density decreases then to 0.13gcm-3
at 11.5cm; this is followed by a small peak at 10.5cm, where the
density is 0.16gcm-3
. There is another peak at 3.5cm; here the density is 0.07gcm-3
.
4.43 SCP Concentrations
There are three peaks shown in the SCP profile, as shown in figure 31, the first is at 20.5cm, the
concentration is 43556.38gDM-1
. This is followed by a decrease in concentration, then another peak
in concentration at 14.5cm, where the concentration is 81452.12gDM-1
. There is then a small
decrease before another peak in concentration at 9.5cm, the concentration increases to
169602.07gDM-1
.

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4.44 Heavy Metals
4.441 Iron
The iron concentrations in core 4 are shown in figure 32. After 14.5cm there is a very sharp increase
to a peak at 9.5cm, this is where the maximum concentration occurs, 34752ppm. From 9.5cm to
0.5cm the concentration declines steadily to 195ppm, the minimum concentration.
4.442 Copper
There is a steady increase in copper concentration between 29.5cm and 18.5cm (Figure 33) from
0ppm to 24ppm. There is a peak at 11.5cm, where the concentration is 229ppm. Between 11.5cm
and 3.5cm there is a sharp decrease to 0ppm, from here to the surface there is none present.
4.443 Zinc
Figure 34 shows the concentration of Zinc for core 4. There are two spikes in concentration in a
trend which otherwise shows a tendency to decrease from base to surface. The first peak is at
21.5cm, where the concentration is 128ppm. There is then a decrease to 15.5cm where the
concentration is 70ppm. There is then another peak at 8.5cm where there is an increase in
concentration to 213ppm, this is the maximum concentration. There is then a rapid decrease to the
surface, at 0.5cm 36ppm.
4.444 Lead
There are 2 peaks shown in the lead concentration for core 4 (Figure 35). The concentration steadily
increases between 29.5cm and 13.5cm, this is where the first peak in concentration is, and the
concentration here is 1179ppm. After this point there is a small decrease to 1050ppm at 12.5cm.
There is then a small peak at 11.5cm where the concentration is 1178ppm. After this point the
concentration steadily decreases to 5ppm at 0.5cm.

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5.0 Explanation
5.1 Bleasdale Core 1
SIRM shows the quantity of magnetic material (Jones et al., 2014, Thompson and Oldfield, 1986).
Therefore in core 1 magnetic minerals are only in significant quantities after 8.5cm (Figure 3), this
rapid hike in the quantity of magnetic minerals is known as take-off. After take-off there are two
significant peaks in the quantity of magnetic minerals, the first peak at 5.5cm is smaller than the
second, which is at 3.5cm. Between 7.5cm and 11.5cm there is a drop in the IRM-20mT/SIRM and the
IRM-40mT/SIRM ratios, this is indicative of hard behaviour, and could be associated with haematite, or
it could be an antiferromagnetic component (Edge Hill University, date unknown, Thompson and
Oldfield, 1986). The SIRM/ARM changes show that there are peaks in coarse grained magnetic
material at 1.5cm, 4.5cm, and 8.5cm (Figure 4). The values between 8.5cm and the top of the core
are greater than 200, indicative of coarse grained ferrimagnetic material (Edge Hill University, date
unknown).
5.12 Heavy Metals
The heavy metals for core 1 indicate that the peat has received atmospheric input, but there is also
some indication of the metals being mobile. Iron (Figure 6) shows a significant increase in
concentration after 10.5cm to the surface, this is the same as the increase in SIRM; there is also a
peak in concentration at 3.5cm, which is the same as SIRM changes. However, there is a peak further
down the core at 18.5cm, this is well before the SIRM take-off, this would indicate that either there
is a different source, or that there has been movement (Hutchinson and Armitage, 2008). The
copper concentration indicates a purely atmospheric input with little or no movement (Figure 7), this
is because there is none present in the core after 3.5cm. Zinc concentrations for core 1 show that
there may have been some movement (Figure 8), this is because of the relatively high
concentrations found in the core after the SIRM take-off depth, the shallowest depth at which none

P a g e | 55
is found is 24.5cm. Lead concentrations for core 1 are very similar to iron (Figure 9); However, there
is a high concentration present after the take-off depth, there is a substantial peak between 12.5cm
and 18.5cm, because there is no peak in the SIRM at this point it indicates that there may have been
some movement after deposition.
5.13 Bulk Density
Bulk density shows the changes in density of organic material, it has been suggested that when there
is a peak in the organic density there can be a concentration of particulates (Olid et al., 2010).
However, there are no peaks in magnetic minerals or heavy metals where there is a peak in density
(Figure 5), suggesting that the changes are not affected by this.
Core 2 SIRM changes show that take off is at 15.5cm (Figure 11), this is where there is a significant
increase in the quantity of magnetic minerals present (Thompson and Oldfield, 1986, Jones et al.,
2014). The other increases are at 5.5cm, 3.5cm and 0.5cm. The reverse field ratios show that there is
a drop in all four of the reverse fields present around the same depth that SIRM appears to take-off,
18.5cm; this is the hard feature (Thomson and Oldfield, 1986). It may suggest that there is either fine
ferromagnetic material present or a significant antiferromagnetic component (Edge Hill University,
date unknown). At 8.5cm there is a peak in the IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-300mT/SIRM
ratios, but there is a drop in the IRM-20mT/SIRM, this may suggest that there is no antiferromagnetic
material present, only soft ferrimagnetic minerals (Edge Hill University, date unknown). The drop
between 8.5cm and the surface in the IRM-40mT/SIRM, IRM-100mT/SIRM and IRM-300mT/SIRM suggests
that there is an increase in the amount of fine grained ferrimagnetic material present, either that or
there is a significant antiferromagnetic component (Edge Hill University, date unknown). The
SIRM/ARM changes suggest that there is an increase in fine grained ferrimagnetic minerals at 5.5cm
and at 2.5cm, but there is an increase in coarse grained ferrimagnetic material at 6.5cm and at

P a g e | 56
4.5cm (Figure 12), however, at low values the reliability of this parameter is dubious (Thompson and
Oldfield, 1986).
5.22 Heavy Metals
The heavy metal changes for core 2 show some correlation with the magnetic minerals. Iron
concentrations steadily increase from 18.5cm, where the magnetic mineral measurements suggest
that take-off is. There is some iron present after this depth (Figure 14), this is indicative of
movement as there should not be any present below this depth as heavy metals in the atmosphere
have existed only since the industrial revolution (Yang et al., 2001). The copper changes (Figure 15)
indicate that copper has had no movement; this is due to the fact that what little there is present
only until 5.5cm, well before the take-off depth. The zinc changes show that the concentration
increases from the take-off depth at 15.5cm, but there is a peak at 0.5cm, 3.5cm and 5.5cm, the
same depths at which there are peaks in the SIRM (Figure 16). The fact that there is still some zinc
present after the take-off date suggests that there has been a little movement. The lead
concentration changes (Figure 17) show that the concentration gently increases after the take-off
depth, 18.5cm. There is also a peak at 3.5cm; there is a peak in SIRM here as well. The low
concentrations after this depth suggest that there has been some movement down profile.
5.23 Bulk Density
The Bulk density changes for core 2 (Figure 13) indicate that there is a high bulk density at 0.5cm,
6.5cm and 7.5cm. 0.5cm is a significant depth for SIRM changes and zinc concentration; this may
suggest that the increases in both these variables at this point may be a result of an increase in bulk
density (Thompson and Oldfield, 1986). There is also a peak in the SIRM concentrations at 6.5cm;
this may also be a concentration of particulates due to the increase in organic matter (Thompson
and Oldfield, 1986).

P a g e | 57
Core 3 SIRM indicates that take off is at 16.5cm, where the first significant increase in magnetic
minerals occurs (Figure 19). There are six increases in the quantity of magnetic minerals; these are at
12.5cm, 10.5cm, 8.5cm, 4.5cm, 2.5cm and 0.5cm. The peak at 10.5cm is much larger than the others;
this could be an indicator of a past fire (Hutchinson and Armitage, 2005). Fire enhances the magnetic
signal given in a sample; it gives weak or non-magnetic minerals a stronger signal, thus appearing to
increase the quantity (Thompson and Oldfield, 1986, Jones et al., 2014 and Hutchinson and
Armitage, 2005). The reverse field ratios show no hard feature or any fluctuations (Figure 19). The
fact that there are no features, may suggest that the magnetic material is ferrimagnetic, or that the
peat has remained dry enough to prevent dissolution of soft magnetic minerals, which would leave
behind a hard magnetic signal (Oldfield, 2015). The SIRM/ARM concentrations show that there is a
peak in coarse grained ferrimagnetic material at 14.5cm, followed by a peak in finer grained material
at 15.5cm (Figure 20).
5.32 SCPs
The SCP concentration shows that there is a higher concentration of SCPs at 19.5cm and 12.5cm
(Figure 22). A high concentration of SCPs indicates a higher deposition of soot particulates, a
pollution indicator (Rose et al., 1999). There is a lower concentration at 21.5cm and 15.5cm; this is
an indication of lower pollution and deposition.
5.33 Heavy Metals
If SIRM changes show that take off is at 16.5cm, any heavy metals deeper than this are most likely a
result of movement down profile, rather than direct deposition. Iron shows that the concentration
increases after the take-off depth (Figure 23), this is consistent with atmospheric deposition. There
are also peaks in concentration at 0.5cm, 2.5cm, 4.5cm and 12.5cm, the same depths that SIRM
concentrations peak. However, the high concentrations found below the take-off depth suggest that

P a g e | 58
there has been some movement down profile. The copper concentrations show that there is an
increase in concentration from the take-off depth (Figure 24). The main peak in copper is at 10.5cm,
there is a peak in SIRM at this depth as well, and there are also peaks at 4.5cm, 2.5cm and 0.5cm,
also consistent with the SIRM changes. The small amount of copper present below the take-off
depth; this suggests that there has been some movement. The zinc concentration shows that there
is some movement of zinc compared to the magnetic minerals; this is because there is a high
concentration present after the SIRM take-off (Figure 25). The peaks in zinc are at the same depth as
those in the SIRM, they are at 10.5cm, 2.5cm and 0.5cm. The lead concentrations clearly show that
there is an increase after the SIRM take-off depth (Figure 26). There is also a small increase around
the hard feature depth as well, this may suggest that there has been some dissolution of the soft
ferrimagnetic material and the heavy metals have moved (Oldfield et al., 2015).
5.34 Bulk Density
The bulk density peaks at 7.5cm, none of the other variables have a significant increase at this depth
(Figure 21). This suggests that any peaks or increases are not a result of an increase in organic matter
which can concentrate metals and magnetic minerals (Olid et al., 2010).
Core 4 shows two smaller peaks at 14.5cm and 12.5cm in the SIRM (Figure 28), on the reverse field
ratios there is a significant drop in all four, this drop indicates a heard feature, or a significant
antiferromagnetic component (Thompson and Oldfield, 1986 and Edge Hill University, date
unknown). The highest peak in SIRM, and therefore the highest quantity of magnetic minerals, is at
10.5cm, after the hard feature. The reverse field ratios show an increase in percentage suggesting
that the high quantity of magnetic material is mainly soft ferrimagnetic material. The highest peak in
SIRM/ARM is at 4.5cm (Figure 29), there are other peaks at 13.5cm and 7.5cm. This means that
there is an increase in coarse ferrimagnetic material at these depths.

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5.42 SCPs
The SCP concentrations are lower inside the hard feature (Figure 31), the highest concentration of
SCPs are above this feature. However, there is an increase at the same depth that there is an
increase in percentage in all four reverse fields and the SIRM, at 14.5cm.
5.43 Heavy Metals
The heavy metal changes for core 4 show that iron changes are fairly consistent with the SIRM
changes (Figure 32), there is an increase in concentration above the take-off depth. There is a high
SIRM where the maximum concentration is. There is a peak below the take-off depth; this is
significant as it may indicate some mobility. The highest concentrations of copper are within the
hard feature zone (Figure 33), there is less in the soft magnetic zone nearer the surface and below
the hard feature. There are only very low concentrations below the hard feature, suggesting that
there has been little movement of the metals, at least to this depth. The zinc concentrations show
that the highest concentrations are above the hard feature and the peak in SIRM (Figure 34). But
there is a peak below the take-off around 21.5cm, this may be indicative of movement. The
concentrations of lead (Figure 35) show that the main peak is within the hard feature and the
concentration falls away either side of the feature. There does not seem to be much movement
below the take-off depth.
5.44 Bulk Density
Bulk density increases at the same depth that the SIRM is at its highest (Figure 30), this may suggest
that this peak is due to a higher amount of organic matter concentrating the amount of magnetic
minerals there are at that depth (Olid et al., 2010).

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6.0 Comparison
All four of these cores have come from different areas within the Forest of Bowland; therefore, it is
reasonable to suggest that there may be differences between the quantities of heavy metals,
magnetic minerals and SCPs.
Table 1 lays out the quantity of magnetic minerals and the cumulative lead concentration for each
core, lead has been used because, as it has already been discussed, it has moved the least and this
record is more intact.
Core Number Cumulative SIRM
(Am2
kg-1
g-1
)
Cumulative Lead Concentration
(ppmg-3
)
1 407734.8 (third
highest)
27780.96 (third highest)
2 9393.4 (lowest) 19424.09 (lowest)
3 497451.4 (second
highest)
76214 (second highest)
4 760528.5 (highest) 208203 (highest)
Table 2: quantity of pollution, from SIRM and lead pollution, for each core
Conclusively it shows that core 4 has the highest cumulative SIRM, and lead concentrations. It also
shows that core 3 has the second highest concentration of variables. Core 1 has the third highest
cumulative lead and SIRM, and core 2 has the lowest cumulative lead concentration and SIRM.
6.1 Magnetic Minerals
The SIRM changes show that the cores vary in the total quantity of magnetic minerals and the depth
at which take off occurs. The total quantity of magnetic minerals may differ because of the input
amount, this is the distance decay aspect of the study, and it has been shown that peat bogs nearer
a source of pollution contain more pollutants (Thompson and Oldfield, 1986, Oldfield et al., 2015
Marx et al., 2010 and Oldfield, 2015). However, the quantity may also be affected by dissolution;
wetter bogs will dissolve more magnetic minerals (Rothwell and Lindsay, 2007), and therefore
reduce the quantity present. It has been shown that wetter areas on the same bog have differing
magnetic properties to drier areas (Rothwell and Lindsay, 2007). If an area is wetter and dissolution

P a g e | 61
of magnetic minerals begins the coarser magnetic minerals begin to dissolve first, leaving behind a
lower SIRM and a drop in reverse fields, a hard feature (Rothwell and Lindsay, 2007). This difference
in magnetic mineral type and their rates of dissolution is due to the two main types of magnetic iron
minerals, magnetite and haematite. Haematite has a much stronger resistance to corrosion than
magnetite, haematite is produced when the outer coating of magnetite is corroded away, and
haematite concentrations are indicated through hard magnetic mineral behaviour (Jones et al.,
2014, Oldfield et al., 2015). The depth at which take off occurs varies from core to core. This can be a
result of different dates that pollution reaches an area, for example, work completed in the
Pennines and in the Southern Lake District show that the latter receives pollutants at a later stage
than the former (Oldfield, 2015). However, the differing depth can also be as a result of the rate of
peat accumulation, the slower the rate of accumulation the higher the total concentration of
magnetic minerals (if there is a constant supply) and the shallower the take-off depth, this is because
the same layer remains on the surface for longer before it is buried (Rothwell and Lindsay, 2007).
Comparing the reverse field ratios for all four cores shows that cores 1, 2 and 4 all have a zone of
hard magnetic remanence in the reverse field ratios indicating an increase in the amount of fine
ferrimagnetic material or an antiferromagnetic component (Jones et al., 2014, Edge Hill University,
date unknown). Core 3 has no change in the reverse fields, this may be an indicator of a drier peat
bog, with no dissolution of soft ferrimagnetic minerals, if the bog was wetter and dissolution had
occurred there would be some fluctuation and possibly a hard feature present around the take-off
depth. Because there is not much fluctuation it suggests that all the soft magnetic material is still
present, magnetite is always found in higher quantities because it is more common than haematite
(Oldfield et al., 2015). The only core that has a hard feature that is not present at the SIRM take-off
is core 2. In this core the hard feature is below take-off, this may imply that there is a small amount
of haematite remaining at this depth, meaning either: there has been some movement of the
magnetic mineral from where it was deposited, or the magnetic material between the SIRM take-off
depth and the hard feature has been completely dissolved. Cores 2 and 4 show the most amount of

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hard magnetic behaviour, the material is not as easily demagnetised, this may suggest that there is
more dissolution in these cores, possibly because the sites are wetter (Oldfield et al., 2015, Rothwell
and Lindsay, 2007), however, it could also suggest there is a significant antiferromagnetic input.
Antiferromagnetism is when the sample is saturated with magnetism and has zero remanence, this
means that the sample is not easily demagnetised (Thompson and Oldfield, 1986), this may indicate
a different source (Hutchinson and Armitage, 2009). The SIRM/ARM shows the nature of
ferrimagnetic minerals, whether they are coarse or fine grained (Thompson and Oldfield, 1986).
However, SIRM/ARM is not particularly reliable when the values are small (Thompson and Oldfield,
1986), this means that fine grained ferrimagnetic material cannot be distinguished from
antiferromagnetic components with any certainty.
6.2 Heavy Metals
Figures 10a, b, c, and d show the relationships between SIRM and iron, copper, zinc and lead
respectively for core 1. The relationship between iron and SIRM shows some positive correlation, as
the amount of iron increases the concentration of SIRM increases (Figure 10a). The relationship
between copper and SIRM shows quite weak positive correlation, so generally as SIRM increases
copper concentration increases as well (Figure 10b). The relationship between SIRM and zinc shows
that an increase in zinc is not reflected in an increase in SIRM (Figure 10c). The lead and SIRM
relationship shows that there is a positive correlation, as SIRM increases, so does the concentration
of lead (Figure 10d). Iron, lead and copper show the strongest correlations. The zinc and SIRM shows
a much weaker correlation; this is because when there is a high zinc concentration, on the whole,
there is no increase in SIRM.
The SIRM and heavy metal correlation graphs for core 2 (Figures 18a, b, c and d) show some positive
correlation; as SIRM increases, the heavy metal concentrations increase. Figure 18a shows the
relationship between SIRM concentration and iron, there is some positive correlation, although it is
not as strong. Figure 18b shows that the correlation between SIRM and copper concentration is

P a g e | 63
positive and fairly strong, as SIRM increases, so does the copper concentration. Copper shows a
stronger relationship than iron. Zinc shows the weakest correlation of the heavy metals for core 2
(Figure18c), showing that when the metal concentration increases, there is no increase in SIRM.
Lead and SIRM show the strongest correlation (Figure 18d).
For core 3 the correlations between heavy metals and magnetic mineral quantities are fairly strong
and positive, therefore, as heavy metals increase the total magnetic mineral quantity increases
(Figures 27a, b, c and d). Iron, copper and lead all have fairly strong positive correlations, as SIRM
increases, the metal concentration increases. The relationship between SIRM and zinc is not as
strong as the other metals, and suggests that there is no relationship.
Figures 36a, b, c and d show the relationships between SIRM and iron, copper, zinc and lead,
respectively for core 4. All the correlation graphs show a fairly strong positive relationship, as the
heavy metal concentration increases the quantity of magnetic minerals also increases. Iron, zinc and
lead show a stronger relationship than zinc (Figures 36a, c and d). Copper shows a slightly weaker
relationship than the other metals in this core, suggesting that copper has moved more in this core
than the others (Figure 36b).
The correlation graphs between SIRM (quantity of magnetic minerals) and heavy metals are a proxy
indicator of the metals moving, in comparison to the magnetics. The correlation graphs comparing
magnetic mineral quantity with heavy metal pollution can be examined to see which element is
most mobile, and which cores have the most movement, i.e. which sites are wetter. Element by
element the data suggests that lead has the strongest correlation, suggesting that it moves less than
some of the other metals. Zinc however, shows the weakest correlation, suggesting that this metal is
the most mobile. Copper and iron have fairly strong correlations, suggesting that they do move, but
not as much as zinc does. Core by core the data shows that core 3 has the strongest correlations;
this suggests that this core is the driest with the least mobility. Core 1 shows fairly strong
correlations, suggesting there is slightly more mobility, that the core is slightly wetter, the same can

P a g e | 64
be said for core 2. However, core 4 shows that the correlation between the heavy metals and SIRM
is weakest in this core, suggesting that this core is much wetter than the others and that there is
more mobility.
6.3 SCPs
SCPs were completed on cores 3 and 4 because of the different magnetic patterns the two cores
had. As a result they both have different SCP patterns. The third core, which magnetic mineral
measurements and heavy metals show to be the driest core, with the least movement of metals and
dissolution of magnetic minerals, increases in SCP concentration from the take-off depth upwards,
which is expected, however there is a spike in concentration below this depth, which may have been
the result of movement. Core 4 on the other hand, which has been shown to be much wetter with
more movement of particulates and dissolution, increases in concentration above the depth at
which magnetic minerals take off, the maximum concentration of SCPs are at the same depth as a
very high SIRM, and there is a decrease in concentration below this depth, suggesting that there is
little movement.

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7.0 Discussion
7.1 Distance Decay
The first objective of this investigation was to find out whether there is a distance decay trend in the
cores from the Greater Manchester area moving North. As shown in figure 2 the sites in order of
increasing distance heading North are core 4, core 1, core 2 and core 3 is furthest North. As such it is
assumed that with increasing distance from the source there will be a decrease in the quantity of
pollution (Marx et al., 2010, Thompson and Oldfield, 1986). Table 2 above shows that core 4 has the
highest cumulative lead concentrations and cumulative SIRM. So if core 4 is nearest to the pollution
source and it is the most polluted, then this follows the same pattern found by (Thompson and
Oldfield, 1986, Marx et al., 2010). However, core 3 is the furthest away from the pollution source,
and all three variables suggest that it is the second most polluted core. Core 1 has higher quantities
of cumulative lead and SIRM than core 2 does, core 1 is slightly further south than core 1, which
means that the distance decay trend works except for core 3, the similarity of the results for cores 1
and 2 is indicative of the small distance between them (Figure 2). The reason why there is not a
distance decay trend is that the record has broken down beyond the point of coherency; this could
be for a variety of reasons.
7.2 Movement of Metals
Movement of metals down profile in this study has shown that zinc is the most mobile metal, this
was also found by Yang et al. (2001), and they also found that lead was the least mobile metal, which
is also what has been found here. Hutchinson and Armitage (2008) also found that zinc penetrated
the furthest down profile. The second peak found before the SIRM take off in iron for cores 1, 3 and
4, and lead in core 1, is found in Hutchinson and Armitage (2008), Thompson and Oldfield (1986),
Schurr, 1983 and Yang et al. (2001). When peaks are found at the same depths they are attributed to
a similar source (Hutchinson and Armitage, 2009), which may partly explain why these peaks occur,
however, the fact that they are found below take off suggests that there has been movement down

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