UK-Finland Sustainability Knowledge Exchange 19-21 October 2020

1. GEOLOGICAL 3D MODELLING SUPPORTING SUSTAINABLE
CHOICES
Hilkka Kallio
Geological Survey of Finland
20.10.2020

2. 3D GEOLOGICAL MODELLING OF SOILS IN
FINLAND
• The Finnish framework for classifying litology doesn’t utilize the
hierarchy of lithostratigraphical codes (supergroup, group, formation,
member and bed). Or does in but in very few places.
• Finnish approach for geological classification is practical and driven by use of data
(agriculture, forestry and engineering)
• also driven by complexity of Quaternary environment
• primary method is morpho-lithogenetic classification for describing Quaternary deposits
• Basically geological 3D modelling can be very easy – all you need is
bolehole logs or/and a geological map with orientation data – dip
direction and dip of each contact
22.10.2020

3. 3D GEOLOGICAL MODELLING OF SOILS IN
FINLAND
• Lack of borehole logs – a lot of site investigations from construction industry
• A lot of in-situ tests (similar like CPT) – few samples
• Traditional geological 3D modelling doesn’t work – need for applied solution
• Interpretation of each in-situ test
• Numeric modeling
• Numeric modeling is typically used when modelling geochemical concentrations in
soil or contamination
• now to be used for drilling resistance
• Drilling resistance data correlation with borehole logs >> stratigraphic profile
• Next step - machine learning for geotechnical profiles (Rob van Putten: Amsterdam
CPTs)
22.10.2020

4. FINNISH SITE INVESTIGATIONS VS. BRITISH
SITE INVESTIGATIONS
• In Finnish Infra format every single field test, sample location or groundwater well is an entity of its own and can be easily
extracted from the infra format file with copy-paste and be used as single object.
• British AGS format splits site investigations in many groups. They can be brought together by ID code.
• In UK the site investigation contractor does a full report of the ground conditions and hands it to the designer
• In Finland the site investigation contractor does only the technical work on the field (drilling, sample taking, monitoring well
installations etc.) based on designers draft and desires. The deliverables are therefore raw compared to AGS
• In UK besides laboratory tests and in situ tests the borehole logs seems be quite common approach when studying ground
conditions.
• material descriptions like color
• sometimes also stratigrafical information
• In Finland most of the site investigations are in-situ tests measuring drill resistance. Borehole logs of unconsolidated material are
not made. However, borehole logs are typical in bedrock surveys.
• The suggested soil type name recorded in Finnish Infra format within the field test result is based on the driller’s interpretation.
Normally it is only based for the fact how hard the soil is to penetrate with the drilling machine.
22.10.2020

5. Percussion drilling (TT = PO) Undisturbed sample (TT = NE) Groundwater well (TT = VP)
Depth, time, soil type (estimated or
observed). Soil type layer bottom =
one row above soil type
abbreviation
Sample top, id, sample bottom, soil type
Sample top, id, sample bottom, soil type
RK = particle size distribution, sieve size,
passing %
LB = laboratory analyses, w = water
content, VG = bulk density, etc.
Water table level, date, top of the well,
bottom of the well, length of the sieve,
mesurer

6. 6
Neil Chadwick, Arup (London, England)
Group Names
LLPL - Liquid and Plastic Limit Tests
LNMC - Water/Moisture Content Test
LOCA - Location Details
MONG - Monitoring Installations and Instruments
"GROUP","ABBR"
"HEADING","ABBR_HDNG","ABBR_CODE","ABBR_DESC","ABBR_LIST","FILE_FSET"
"UNIT","","","","",""
"TYPE","X","X","X","X","X"
"DATA","LOCA_TYPE","CP","Cable percussion (shell and auger)"
"DATA","LOCA_TYPE","IP","Inspection pit"
"DATA","LOCA_TYPE","TP","Trial pit/trench"

7. 23.11.2017Hilkka Kallio

8. HELSINKI
METROPOLITAN
AREA CLAY
22.10.2020
Clay samples in the
field and in the
laboratory
Kuvat Maarit Saresma

9. CLASSIFICATION OF CLAY BASINS IN ORDER TO FIND CHALLENGING AREAS FOR LAND
USE AND CONSTRUCTION DESIGN IN THE CAPITAL REGION OF FINLAND
• Espoo case: potential places for sulphide formation
• Clay depth contours from Espoo region
• Site-specific investigations roughly from 100 locations
• ArcGIS-environment:
• Paleotopography models
• Topography classification
• Litorina water depth analysis
• wind fetch analysis
-> classification of potential sulphide areas
22.10.2020

10. 22.10.202
0
CLAY AREAS AND
DEPTHS
• Thickness of clay
varies between 0-35
m in the Helsinki-
Espoo area
• The thickest clay
deposits contain
young Litorina clay
• Challenging material for
construction

11. PALEOTOPOGRAPHY MODELS
• Reconstruction of
paleotopography in two
stages
• After deglaciation
• During Litorina transgression
Saresma, M., Kosonen, E., Ojala, A. K. E., Kaskela, A. and Korkiala-Tanttu, L. Characterization of sedimentary
depositional environments for land use and urban planning. Bulletin of the Geological Society of Finland. In press.

12. 22.10.202
0
TOPOGRAPHY
CLASSIFICATION
• Classification
using Benthic
Terrain Modeler
• 1) after
deglaciation
• 2) during Litorina
transgression
➢The most
interesting clay
basins -> 2) narrow
depressions
Saresma, M., Kosonen, E., Ojala, A. K. E., Kaskela, A. and Korkiala-Tanttu, L. Characterization of sedimentary
depositional environments for land use and urban planning. Bulletin of the Geological Society of Finland. In press.

13. 22.10.2020
POTENTIAL
AREAS FOR
SULPHIDE
CLAY
Litorina water
depth, Wind
Fetch and site
investigations
Areas in Espoo with potential sulphide clay
Class 1 – very potential (red)
Class 2 – potential (yellow)
Saresma, M., Kosonen, E., Ojala, A. K. E., Kaskela, A. and Korkiala-Tanttu, L.
Characterization of sedimentary depositional environments for land use and
urban planning. Bulletin of the Geological Society of Finland. In press.
Saresma, M., Kosonen, E., Kähkölä, N., Ojala, A. E. K., Auri, J. &
Huusko, A., 2020. Espoon sulfidisavien todennäköiset
esiintymisalueet. Research report GTK/391/03.02/2019,
Geological Survey of Finland, 32 p (in Finnish).

14. GEOLOGICAL MODELING – DEFINITION OF
LAKE WATER INFILTRATION INTO AN
INTERLOBATE ESKER
Mansikkamäki J., Hyvönen A., Putkinen N. and Kallio H. 2020. Dualism of geology
and geotechnical engineering: two parallel approaches to define lake water
infiltration into an interlobate esker. 18th Nordic Geotechnical Meeting. Abstract.
• Geotechnical modeling was conducted using the PLAXIS 2D finite
element analysis
• The most important parameters were permeability parameters and
flow gradient
• Result: infiltration is up to 60 m3/d for the whole planned
reclamation area
A land reclamation project is planned to an area, where lake
water is infiltrated into the Pispalanharju, an important aquifer for
groundwater abstraction.
• 1900 m3/d of groundwater is pumped from several exploitation
wells in Hyhky
• The estimated infiltration rate from the lake into the esker were
1000 m3/d >> forming a significant source of groundwater

15. 22.10.202
0
GEOLOGICAL MODELING –
DEFINITION OF LAKE WATER
INFILTRATION INTO AN INTERLOBATE
ESKER
Mansikkamäki J., Hyvönen A., Putkinen N. and Kallio H. 2020. Dualism of geology
and geotechnical engineering: two parallel approaches to define lake water
infiltration into an interlobate esker. 18th Nordic Geotechnical Meeting. Abstract.
• Thousands of ground investigations was subjected to a
validation process, and some tens of them where chosen for
cross-section created using Groundhog Desktop software
• infiltration rate from precipitation over the modeling area 55%
(330 mm/y) of annual precipitation
• The most important factor for groundwater modeling is to
divide the aquifer area to be modeled into hydraulic
conductivity zones according to the soil material

16. 22.10.202
0
GEOLOGICAL MODELING – DEFINITION OF LAKE
WATER INFILTRATION INTO AN INTERLOBATE ESKER
Flow modeling with GMS software
• single-layer MODFLOW model
(modular 3D finite-difference
groundwater flow model)
• General aim of the model - to
understanding groundwater levels,
flow and discharge directions
• Specific objective for the model –
to define the extent and area of
the exploitation wells affected by
the current groundwater intake,
especially infiltration rate of lake
water
Result:
• the amount of water infiltrating
from the lake is 155 m3/d
• A possible source of
supplementary groundwater for
the aquifer is bedrock fault and
fracture zones that exist in the
vicinity of Hyhky
Mansikkamäki J., Hyvönen A., Putkinen N. and Kallio H. 2020. Dualism
of geology and geotechnical engineering: two parallel approaches to
define lake water infiltration into an interlobate esker. 18th Nordic
Geotechnical Meeting. Abstract.

17. KIITOS
Hilkka.kallio@gtk.fi
www.gtk.fi