1. The document describes 10 stratigraphic formations observed in the Khewra Gorge and Chowa Road section in the Salt Range, including their lithology, age, fossils, and contacts.
2. Key formations discussed include the Salt Range Formation (Precambrian-Cambrian), Khewra Sandstone (Early Cambrian), Kussak Formation (Early-Middle Cambrian), and Jutana Formation (Early-Middle Cambrian).
3. Sedimentary structures observed in the field include ripple marks in the Khewra Sandstone formed by migrating ripples, and cross-bedding characterized by inclined layers within horizontal units.
INTRODUCTION
The Indus Basin of Pakistan is divided into two parts i.e.
3
Lower Indus Basin and Upper Indus Basin. The Upper Indus
Basin is further divided by Sargodha high way into two parts.
Towards the east of the Sargodha highway in Potwar Plateau
and towards the west is Kohat Plateau. The region of the
North Punjab called as Potwar Plateau is bound in the South
by Salt range and in North by MBT as shown below.
INTRODUCTION
The Indus Basin of Pakistan is divided into two parts i.e.
3
Lower Indus Basin and Upper Indus Basin. The Upper Indus
Basin is further divided by Sargodha high way into two parts.
Towards the east of the Sargodha highway in Potwar Plateau
and towards the west is Kohat Plateau. The region of the
North Punjab called as Potwar Plateau is bound in the South
by Salt range and in North by MBT as shown below.
Field Report On Khewra Salt Mine | Report On Khewra Trip | Different Formatio...Faizan Tanoli
Field Report On Khewra Salt Mine | Report On Khewra Trip | Different Formations Of Salt Range Area | Geology | Earth Sciences | Paleontology | Stratigraphy
Lithology
Contacts
Field Report On Khewra Salt Mine | Report On Khewra Trip | Different Formatio...Faizan Tanoli
Field Report On Khewra Salt Mine | Report On Khewra Trip | Different Formations Of Salt Range Area | Geology | Earth Sciences | Paleontology | Stratigraphy
Lithology
Contacts
KSM is 2nd largest and the oldest salt mine in the world. The mines are located in Jhelum District of Punjab, Pakistan. Khewra salt mines are producing more than 350,000 tons per annum of about 99% pure halite. Estimates of the reserves of salt in the mine vary from 82 million tons to 600 million tons. Pakistan is exporting rock salt to all over the world. The earnings from the mines can be increased manifolds with the adoption of latest technology for salt production.
Geology and Stratigraphy of Hazara,Mansehra and Oghi Khaki Road PakistanHammad Ahmad Sheikh
A detail field report on Stratigraphy of the the Hazara Basin,Mansehra and Oghi Khaki Road.
Beside this there is a detailed description on the Drilling Rig and working and One day visit to Tarbela Dam.
Petroleum system, facies analysis and sedimentology of jurassic - cretaceous ...FatimaNasirQureshi
sedimentological differences of jurassic-cretaceous rocks in Hazara and Kohat Basin including their petrochemical analysis and depositional envoirnments
Stratigraphy of Jhelum group (khewra formation, khussak formation, jutana formation, baghanwala formation), its lithology, fossils, thickness, environment of deposition etc.
This time the slide rock mainly contains what Huangshan has seen and heard, as well as the resolution of stone sampling and the final understanding of the law.
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
1. Khewra Gorge and Chowa Road section Day 1
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Stratigraphic Sequence in Salt Range
Age Group Formation
Pleistocene Kalabagh Cong Mansehra S/St.
Conglomerate.
Pliocene, Late Miocene Siwalik Group Soan Formation
Dhok Pathan Formation
Nagri Formation
Chingi Formation
Early Miocene Rawalpindi Group Kamlial Formation
Murree Formation
MAJOR UNCONFORMITY
Early Eocene Charrat Group Chor Gali Formation
Sakesar Limestone
Nammal Formation
Makarwal Group Patala Formation
Lockhart Formation(Khanabad)
Hungu (Dhak Pass)
MAJOR UNCONFORMITY
Early Cretaceous (Early
Cretaceous and Late
Jurassic)
Surghar Group Lumshiwal Formation
Chichali Formation
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UNCONFORMITY
Middle Jurassic Baroch Group
Samanasuk(Baroch Limestone)
Shinawari Formation
Datta Formation (Variegated
beds)
UNCONFORMITY
Late Triassic Musakhel Group Kingrali (Kingrali Dolomite)
Tradian Formation
Mianwali Formation
PARACONFORMITY
Late Permian Zaluch Group Chiddru Formation (Upper
Productus)
Wargal Limestone (Middle
Productus)
Amb Formation (Lower
Productus)
Early Permian Nilawahan Group Sardhai Formation
Warchha Formation
Dondot Formation
Tobra Formation
Major UNCONFORMITY
3. Khewra Gorge and Chowa Road section Day 1
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On day one, we went to the Khewra Gorge located in Eastern Salt Range. We observed different
formations. They are explained below
Salt Range Formation:
Synonym: Wynne (1878) named and described the formation as ‘Saline Series’. Gee (1945)
called the same unit as ‘Punjab Saline Series’. The present name, the Salt Range Formation has
been given by Asrarullah (1967).
Type Locality: Punjab, Khewra Gorge in the eastern Salt Range has been designated as its
type locality.
Age:The age of Salt Range Formation is late Precambrian or early Cambrian.
Lithology: The lower part of the Salt Range Formation is composed ofred-coloured gypseous
marl with thick seems of salt while the beds ofgypsum, dolomite, greenish clay and low grade
Middle and Early
Cambrian
Jehlum Group Baghanwala Formation (Salt
Pseudomorph Beds)
Jutana Formation (Magnesium
Sandstone)
Kussak Formation (Glauconitic
Sandstone)
Khewra Sandstone (Purple
Sandstone)
Pre Cambrian Salt Range Formation (Saline
Series)
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oil shale are the constituents of the upper part. A highly weathered igneous body knownas
“Khewra Trap” has been reported from the upper part of the formation. It consists of highly
decomposed radiating needles of a light-coloured mineral, probably pyroxene. The red-
coloured marl consists chiefly of clay, gypsum and dolomite with occasional grains and crystals
of quartz of variable size. Thick-bedded salt shows various shades of pink colour and well-
developed laminations and colour bandings upto a metre thick. The gypsum is white to grey in
colour. It is about 45m thick, massive and is associated with bluish grey, clayey gypsum. The
dolomite is usually light grey in colour and flaggy.
It has three members:
1. Sahwal Marl Member.
2. Bhandar Kas Gypsum Member.
3. Billianwala Salt Member.
Fossils:It is devoid of fossils.
Contacts:Its upper contact is with Khewra Sandstone which is normal and conformable and
lower contact with metamorphic rocks of Precambrian age.
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Fig .1 Gypsum beds of Salt Range Formation in Khewra gorge.
2. Khewra Sandstone:
Synonym: The name was originally proposed by Noetling (1894) as ‘Khewra Group’. Prior to
that Wynne (1878) called the formation “Purple Sandstone Series” and this name was
continued until recently when the name of the formation was formalized as “Khewra
Sandstone” by the Stratigraphic Committee of Pakistan.
Type Locality: The type locality is in Khewra Gorge near Khewra Town, Salt Range.
Age: The age of Khewra Sandstone is early Cambrian.
Lithology: The formation consists predominantly of purple to brown and yellowish brown
fine-grained sandstone. The lowermost part of the formation is red flaggy shale. The sandstone
is mostly thick bedded to massive. The Khewra Sandstone is widely distributed throughout the
Salt Range.
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Fossils:The formation contains only a few trace fossils in the Salt Range which have been
interpreted as trilobites.
Contacts:Upper contact is with Kussak Formation which is gradational and lower contact with
Salt Range Formation.
Fig 2.Purple sandstone with honey comb weathering in Khewra Sandstone.
3.Kussak Formation:
Synonym: Wynne (1878) applied the name ‘Obulus beds’ or ‘Siphonotreta beds’ to a
predominantly greenish grey, glauconitic, micaceous sandstone and siltstone. Waagen (1895)
used the name ‘Neobolus beds’ for the same unit. Noetling (1894) proposed the name ‘Kussak
Group’ and finally the Stratigraphic Committee of Pakistan named the Formation as “Kussak
Formation”.
Type Locality: The type locality lies near the Kussak Fort in the eastern part of the Salt Range.
Age:The age of the formation is either late early or early middle Cambrian.
7. Khewra Gorge and Chowa Road section Day 1
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Lithology:The formation is composed of greenish-grey, gluconitic, micaceous sandstone,
greenish-grey siltstone, interbedded with light grey dolomite and some oolitic, arenaceous
dolomite. Numerous layers of intraformatinal conglomerate are present. Pink gypsum lenses
are present near the top. The general lithology throughout the formation is uniform. However,
thickness vary at different places.
Fossils:The formation is fossiliferous and has yielded the following fauna: Neoboluswarthi,
Bolsfordla granulate, Lingulellawanniecki, Redlichtanoetlingi.
Contacts: Upper contact is with Jutana Formation which is conformable and lower contact
with Khewra Sandstone which is gradational.
Fig 3. Shale and micaceous silt stone of Kussak Formation.
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4. Jutana Formation
Synonym: Fleming (1853) named this unit “Magnesian sandstone”. Noetling (1894) described
it as ‘Jutana Stage’. The Stratigraphic Committee of Pakistan formalized the name as “Jutana
Formation”.
Type Locality: The type locality lies near Jutana Village in the eastern Salt Range.
Age: It is early middle Cambrian or late early Cambrian.
Lithology:At the type locality the lower part of the formation consists of light green, hard
massive, partly sandy dolomite and the upper part is composed of light green to dirty white
massive dolomite. In the upper part, brecciated dolomite is also present with matrix and
fragments consisting of same rock.
Fossils:It contains Lingulellafushi, Botsfordia granulate, Redilchianoetlingi,
Pseudothecasubrugosa.
Contact:The formation is conformably underlain by the Kussak Formation and conformably
overlain by the Baghanwala Formation.
Fig 4.Massive dolomite of Jutana Formation.
9. Khewra Gorge and Chowa Road section Day 1
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5. Baghanwala Formation:
Synonym: The name Baghanwala Formation is now given to the rocks of the ‘Pseudomorph
Salt Crystal Zone’ of the Wynne (1878) and the ‘Baghanwala Group’ of Noetling (1894). Holland
(1926) called these beds “Salt Pseudomorph be ds” and Pascoe (1959) named them
“Baghanwala Stage”.
Type Locality:It is near Baghanwala Village in the Eastern Salt Range.
Age: Early middle Cambrian
Lithology: The formation is composed of red shale and clay, alternating with flaggy sandstone.
The flaggy sandstone exhibits several colours including pink grey or blue green, especially in the
lower half of the formation.
Fossils:Devoid of fossils.
Contact:The contact of the Baghanwala Formation with the overlying Tobra Formation is
unconformable, whereas the lower contact with the Jutana Formation is conformable.
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Fig 5.Flaggy sandstone beds and shales in Baghanwala Formation.
6. Tobra Formation:
Synonym: It was previously known in the literature as “Talchir Boulder Bed” or “Talchir Stage”
of Gee and “Salt Range Boulder Bed” of Teichert (1967).
Type Locality:The type locality is located near Tobra Village in the eastern Salt Range.
Age: Early Permian
Lithology:The Tobra Formation depicts a very mixed lithology in which the following three
facies are recognized
1. Tilliticfacies exposed in the eastern Salt Range. This rock unit grades into marine
sandstone containing Eurydesma and Conularia fauna
2. Freshwater facies with few or no boulders. It is an alternating facies of siltstone and
shale containing spore flora.
3. A complex facies of diamictite, sandstone and boulder bed.
In the eastern Salt Range the Tobra Formation exhibits true trillite; the rock unit is composed of
boulders of granite with fragments of quartz, feldspar, magnetite, garnet, clay stone, siltstone,
quartzite, bituminous shale and gneiss. The matrix of the conglomerate bed is generally clayey,
sandy and at some places calcareous.
Fossils:Pollens and spores, Punctatisporites, Leiotriletes, Protohaploxypinus, and
Striatopodocarpites.
Contact:Upper contact with Dandot Formation which is gradational lower contact with
Cambrian rocks(Baghanwala Sandstone) which is disconformable.
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Fig 7.Tilaticfaciesof Tobra Formation.
7. Dandot Formation:
Synonym: The name Dandot Formation is formalized after the ‘Dandot Group’ of Noetling
(1901) and includes the “Olive Series”, ‘ Eurydesma beds’ of Wynne (1878) and the ‘Speckled
sandstone’ of Waagen (1879).
Type Locality: The type locality is near Dandot Village, eastern Salt Range.
Age:Early Permian.
Lithology:The lithology at the type locality consists of light grey to olive green yellowish
sandstone with occasional thin pebbly beds and subordinate dark grey and greenish splintery
shale.
Fossils: The Dandot Formation is fossiliferrous and the basal part in the eastern Salt Range has
yielded brachiopods including Discina species, Martiniopsis species and Chonetes species.
Contact:The formation has a gradational contact with the underlying Tobra Formation and is
terminated in sharp but conformable contact with the overlying Warchha Sandstone.
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Fig 8.shales and pebbly beds of sandstone in Dandot Formation.
8. Patala Formation:
Synonym: The term Patala Formation was formalized by the Stratigraphic Committee of
Pakistan for the “Patala Shale” of Davies and Pinfold (1937) and its usage was extended to other
parts of the Kohat-Potwar and Hazara areas.
Type Locality: The section is exposed in Patala Nala in the Salt Range.
Age:Late Paleocene
Lithology:The Formation consists of shale and marl with subordinate limestone and
sandstone. The shale is dark greenish grey, selenite bearing, in place carbonaceous and
calcareous, and also contains marcasite nodules. The limestone is white to light grey with
nodules. It occurs as interbeds. Subordinate interbeds of yellowish brown and calcareous
sandstone are present in the upper part. Coal seams of economic value are present locally.
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Fossils:Forams, molluses and ostracodes. Actinosiphontibetica, Assilinadandotica,
Discicyclineranikotensis, Lockhartiaconditi, Nummulitesgloblus, Globigerina linaperta.
Contact:Upper contact conformable and transitional with Namal Formation and lower contact
conformable with Lockhart Limestone.
Fig 9.Shale , and fire clays of Patala Formation.
9. Namal Formation:
Synonym: The term Nammal Formation has been formally accepted by the Stratigraphic
Committee of Pakistan for the “Nammal Limestone and Shale” of Gee (in Fermor, 1935) and
“Nammal Marl” of Danilehik and Shah (1967) occurring in the Salt and Trans Indus Ranges.
Type Locality: The section is exposed in the Nammal Gorge (lat. 32˚ 40˚ N :lon. 71˚ 07’ E) is
the type section.
Age:Early Eocene.
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Lithology: The formation, throughout its extent, comprises of shale, marl and limestone. In
the Salt Range, these rocks occur as alternations. The shale is grey to olive green, while the
limestone and marl are light grey to bluish grey. The limestone is argillaceous in places.
Fossils:Forams and moluscs, Assilinagranulosa, Discocyclinaranikotensis etc.
Contact:Upper contact transitional with sakeser limestone and lower contact with Patala
Formation which is transitional.
Fig 10.Nodular Limestone of Nammal Formation.
10. Sakesar Limestone:
Synonym:The term Sakesar Limestone was introduced by Gee for the most prominent Eocene
limestone unit in the Salt Range and Trasns-Indus Ranges.
Type Locality: Sakesar Peak in the Salt Range has been designated as the type locality.
Age: Early Eocene
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Lithology:The unit consists dominantly of limestone with subordinate marl. The limestone,
throughout its extent, is cream coloured to light grey, nodular, usually massive, with
considerable of chert in the upper part. The marl is cream coloured to light grey and forms a
persistent horizon near the top.
Fossils: Foramsmolluscs and echinoids, Assillinalaymeriei, Flosculineglobosa, Lockhartiaconditi
etc.
Contact:Upper contact conformable with Chorgali Formation and lower contact with Namal
Formation which is transitional.
Fig 11. Cherty nodules in massive limestone of Sakaser Limestone.
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Sedimentary Structures Observed in Eastern Salt Range:
Ripple Marks:
Ripple cross-laminae forms when deposition takes place during migration of current or
wave ripples. A series of cross-laminae are produced by superimposing migrating ripples.
The ripples form lateral to one another, such that the crests of vertically succeeding laminae
are out of phase and appear to be advancing upslope. This process results in cross-bedded
units that have the general appearance of waves in outcrop sections cut normal to the wave
crests. In sections with other orientations, the laminae may appear horizontal or trough-
shaped, depending upon the orientation and the shape of the ripples. Ripple cross-laminae
will always have a steeper dip downstream, and will always be perpendicular to paleoflow
meaning the orientation of the ripples will be in a direction that is ninety degrees to the
direction that current if flowing. Scientists suggest current drag, or the slowing of current
velocity, during deposition is believed to be responsible for ripple cross-laminae. In the field
we identify ripple marks in Khewra Sandstone.
Ripple Marks
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Cross Bedding:
In geology, the sedimentary structures known as cross-bedding refer to (near-) horizontal units
that are internally composed of inclined layers. This is a case in geology in which the original
depositional layering is tilted, and the tilting is not a result of post-depositional deformation.
Cross-beds or "sets" are the groups of inclined layers, and the inclined layers are known as cross
strata.
Cross bedding forms during deposition on the inclined surfaces of bedforms such as ripples and
dunes, and indicates that the depositional environment contained a flowing medium (typically
water or wind). Examples of these bedforms are ripples, dunes, anti-dunes, sand waves,
hummocks, bars, and delta slopes. In the field we observed cross bedding in Khewra Sandstone.
Cross Bedding
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Mud Cracks:
Mud cracks (also known as desiccation cracks or mud cracks) are sedimentary structures formed
as muddy sediment dries and contracts. Naturally forming mud cracks start as wet, muddy
sediments desiccates, causing contraction. A strain is developed because the top layer tries to
shrink while the material below stays the same size. When this strain becomes large enough,
channel cracks form in the desiccated surface material, relieving the strain. Individual cracks
spread and join up forming a polygonal, interconnected network. These cracks may later be filled
with sediment and form casts on the base of the overlying bed.
Mud Cracks
Honey Comb Weathering:
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Honeycomb weathering, also known as fretting, cavernous weathering, alveoli/alveolar
weathering, stone lattice, stone lace is a type of salt weathering common on coastal and semi-arid
granites, sandstones and limestone. Honeycomb weathering is not limited to natural settings and
can be seen to develop on buildings where a rate of development can be established. This rate
can be as fast as several centimeters in 100 years.
Cause
For honeycomb weathering to occur, a source of salt is needed because the basic mechanism for
this kind of weathering is salt heaving. Salt is deposited on the surface of the rock by saltwater
spray or by wind. Moisture must be present to allow for the salt to settle on the rocks so that as
the salt solution evaporates the salt begins to crystallize within the pore-spaces of the rock.
Porous rock is also needed so that there are pore-spaces for the salt to crystallize within. These
salt crystals pry apart the mineral grains, leaving them vulnerable to other forms of weathering. It
takes prolonged periods for this weathering to become visible, as the rock goes through cycles of
wetting and drying. We observed the honey comb weathering in Khewra Sandstone.
Honey comb Weathering
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Convolute Bedding:
Convolute bedding forms when complex folding and crumpling of beds or laminations occur.
This type of deformation is found in fine or silty sands, and is usually confined to one rock layer.
Convolutelaminations are found in flood plain, delta, point-bar, and intertidal-flat deposits.
They generally range in size from 3 to 25 cm, but there have been larger formations recorded as
several meters thick. We also observed it in Khewra sandstone.
Convolute Bedding
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Pseudomorph Salt Crystals:
In mineralogy, a pseudomorph is a mineral or mineral compound that appears in an atypical
form (crystal system), resulting from a substitution process in which the appearance and
dimensions remain constant, but the original mineral is replaced by another. The name literally
means "false form". We observed it in Baghanwala Formation.
Pseudomorph Salt Crytals
Load Casts:
Load casts or Sole marks are sedimentary structures found on the bases of certain strata that
indicate small-scale (usually on the order of centimeters) grooves or irregularities. This usually
occurs at the interface of two differing lithologies and/or grain sizes. They are commonly
preserved as casts of these indents on the bottom of the overlying bed (like flute casts). This is
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similar to casts and molds in fossil preservation. Occurring as they do only at the bottom of
beds.
Load Casts
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Hoddows Structures:
These are Hoddows structures which are found in Salt Range Formation.
Chopboard weathering:
We observed chopboard weathering in Jutana Dolomite.
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Stalactite
Burrows: