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Department Of Geology
Geology Field Report
Submitted By Ubaid Ullah
Submitted To Mr Jehan Zeb Khan
Field Date 24-25-26 March 2016
Submitted Date 03 Aprill 2016
Roll No#1408
Cell#+923441190391
Preface
Stratigraphy of Salt Range
Our Approach
Today's student of tomorrow 's decision makers ,whether their careers are in politics ,finance ,technology ,medicine, geology, or other science. It is their decision that collectively will decide the fate of our planet earth. the instructor in Earth sciences or geology must ensure that their students have the opportunity to obtain a basic understanding of earth so that they are equipped to make informed ,environmentally responsible decision in their future careers .
I will definitely say that our teachers instructor helped us a lot in attaining goals that were selected for we students during Salt Ranges (lesser Himalayas ) held on 24,25,26 March 2016.I convey the message that understanding the Earth is exciting and that it entireness and heightens our sense of awareness of the world around us.
Our field to salt ranges was to recognize and understand various lithologies ,structures, fossils, economically importance mines in the sedimentary strata ranging from Cambrian to recent age of the geologic time scale .If at the end of my report you argue to have a glance over again. Then I will have definitely done my best job in preparing and achieving the goals through the ever best help of my teachers
Organization of the reports
The report is divided into three days of into Central ,western and eastern salt ranges, various formation ,groups ,and members of the formation in salt ranges. All these three days study deals lithologies, Structures, contact and fossil contact all those formation.
Abstract
The Salt Range contains the most important geologic and paleontological localities in Pakistan ,and is one of the outstanding field areas in the entire world. Despite its easy accessibitly ,it has a wealth of geological and paleontological features. In fact ,it represent an open book of geology where is richly fossilferous stratified rocks are very well exposed due to lack of vegetation .these include the Permian Carbonate succession with its outstanding brachiopods fauna ,lower Triassic ammonoid bed ( The mianwali Formation, formerly known as "Ceratite Beds" and lower Tertiary marine strata with age diagnostic foraminifera .These rocks also provide an excellent opportunity for operation of tectonics in the field .
In addition to the easily available geology some prominent gorges provide fantastic location to study the sedimentary succession .Older strata are exposed in the eastern salt ranges between the Khewra -Choa Saidan Shah and Fort Khussak including the famous khewra gorge .In the west ,beyond Kaller kahar ,are younger strata such as in the nilawahan Gorge at Nurpur ,The Nammal Gorge near Mianwali .The Succession has been rightly called a Field Museum f Geology and paleontology and can be classified as one of the great paleontological areas of the world ,fully worth conservation and protection efforts.
Importance of our field
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Stratigraphy of Salt Range
Identification of stratigraphy Different rocks identification . Identification of contact between two formation . Marking of contact between two Formation and understanding of types of contact i.e Sharp
contact and gradational contact. To understand different unconformity like erosinal ,Para Unconformity . To know different types of deposition environment and their diagnostic features. Identification of bedding ,types of bedding (convolute bedding ) ,lamination e,t.c. Identification of different sedimentary structures .e.g. ball and pillow, mud cracks ,cross
bedding, burrows, stylolytes ,algal stromatolites etc. To know the lithology of different Formations from Precambrian to Rcent . To know and determine different fossils in different formation . To understand strike and dip of rocks. And also economic importance of different Formation e.g Nowshehra reef complex and Hungu
coal reservoirs
DAY NO 1st
Stop No 1st
Position No a
kunder Phylite
Phylite is same cleavages like slate .And their protolith is also argelite containing flaky mineral i.e clay which elongated perpendicular to the stresses of metamorphic due to alignment of flaky mineral cleavages developed which is a diagnostic features of phylite and slate .The difference between slate and phylite is that the slate is a fine grain very low grade of metamorphic rocks and phylite is a coarse grain low grade of metamorphic rocks .
Due to type locality it is called in literature kunder phylite because of kunder village
Prograding Metamorphic
The increase in order of metamorphism in rocks to moving towards the mélanges zone is called prograding metamorphic e.g At Attock slate than nowshehra phylite and than Malakand different schist and at Piranu village there is a Chakdara gneiss
Difference between cleavage and Fractures
Fracture have no cohesive forces and irregular in shape . While cleavages have cohesion and will be special pattern.
Age
The age is Ordovician to Silurian.
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Stratigraphy of Salt Range
kundar phylite
Position No b
Contact
there is a sharp contact between kunder phylite and Nowshera Formation .the upper boundary is Nowshera Formation of massive bedding of dolomite and dolomitic limestone. the lower boundary is Kunder phylite of cleavages developed.
lithology and bedding change represent the contact .the abrupt change in lithology and bedding represent the sharp contact and gradational change in lithology and bedding represent gradational contact.
Position No 3
Nowshera Reef Complex
It is also called Nowshera Complex .it is the only reef in whole Asia .
Reef
The colonial growth of organism is called reef .
Environment .
there environment is varies from legonal to intratidal .
Lithology
Dolomite and Dolomitic limestone
diagnostic features
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Stratigraphy of Salt Range
1. Butcher chop weathering .2. Hardness it bounced back the hammer .3. Texture is sugary because it has been metamorphose into dolmitic marble .(when
limestone or dolomite convert to marble it gives sugary textures .the mechanism is the recrystalization of calcite mineral into large crystal .
4. Dissolution cavity .
this cavity is produced in a result of acid rain in which the calcium carbonate convert into ions .if these cavity is small than it is called Honey comb weathering .
5.Effervesce by acid.
molds of trilobites in Nowshera dolmite
Tempestite Bed
The bed which contain almost all types of fossils is called tempestite bed .it represent catastrophic condition .Due to sea level fall death of organism occurred and than preserved
Environment .
Evaporated
Economic Importance
i. The Nowshera reef is richly fossilferous and act as a source rock .because source rock need two reason one is time and permeability and the reef have these i.e time is Ordovician and have high permeability and also act as reservoirs .Mostly Eocene is enough for muture of hydrocarbon.
ii. It is also used as a marble.iii. it have big importance in crushing site also.
Peshawar basin
1. Mardan2. Swabi
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Stratigraphy of Salt Range
3. Peshawar
kambal Pur Basin
1. Hazara2. Mansehra 3. Attock
Upper Indus Basin
It have two portion i.e. Potwar basin or Potwar Plate and kohat basin or plate.
the potwar basin was covered in the field .
kohat basin
1. Dara adam khail 2. kohat3. Parrachenar
Southern Pakistan
It is also called Paradise of Geology and ranges is from Shangla ,Bisham ,Swat.
Northern Pakistan
It is called Museum of Geology in literature and its ranges from sheveshahbazgarrha to Chitral and salt ranges.
The rocks of northern Pakistan is exposed by MMT (main mantle thrust) and MKT (Main kurrakuram thrust)
MBT (main boundary thrust) exposed the rocks of Galyat to Parrachenar and Abottabad .
SRT (salt range thrust ) exposed the rocks of Punjab plane i.e. Precambrian to Recent.
In our field we study S.R.T .Similarly MBT has many splay i.e. Galyat Splay called Nathiagalay splay and exposed murree rocks
Nizampur splay is called Khair abad thrust and exposed rocks of Nizampur
khairmorat thrust exposed the rocks of khairmorat .
Stop No 2nd
Monki slate
Along the motorway there is Monki slate which is effected by great tectonic effect and change into shear zone .these rock is exposed along MBT ( main boundary thrust)
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Stratigraphy of Salt Range
Monki Slate
Chingji Formation
Major Division
Basin Ranges Super Groups Groups Formation Member
Stop No 3rd
Central Salt Range
Rawalpindi Group
1. Murree Formation 2. Kamlial Formation
Siwalik Group
1. Chingji Formation 2. Nagri Formation 3. Dokh Pathan Formation 4. Soan Formation
Chingji Formation
Litholgy
Clay and sandstone .the sandstone is loose because it is a recent deposition and color is maroon
it show the channelize flow of water .Carbonate rocks need marine environment at Eocene time in Pakistan the Thetyan Ocean closed and its water divide into two rivers i.e.
A. Indus river (Tibet to Karachi or North to south )
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Stratigraphy of Salt Range
B. Brahma brothra Indus (way of Bengal)
Environment
it deposit in river system so it is Fluvial. The river system flow always is channelize flow. conglomerate represent floody condition and clay represent calm and cool environment. Murree clay color is maroon. chingji color is brownish grey. Nagri clay color is orange yellowish color due to oxidation reduction environment. And Dokh pathan is compacted sandstone.
Fossils
Vertebrates fossil found in the form of teeth ,lizard, crocodile ,and fish gills. Fluvial along with terrestial fossil live in terrestrial environment and no microfossil because it live in marine environment.
chingji Formation
Stop No 4th
Dokh Pathan Formation
Dokh pathan and Kamlial sandstone show resistance and have ridges because these layers have cementing material.
Dokh pathan sandstone has tourmaline and epidole which differentiate it from other Formation
Age is Pliocene.
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Stratigraphy of Salt Range
Day No 2nd
INTRODUCTIONThe Indus Basin of Pakistan is divided into two parts i.e. 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 is Potwar Plateau towards and the west is Kohat Plateau .The region of the North Punjab called as Potwar Plateau ,is bound in the south of Salt Range and in North by MBT as shown below
The name of Salt range was first use by ELPHISTON in 1808.The name is derived from the fact that the area contains huge reservoirs of the common table salt.
Salt is one of the few most important localities in the Subcontinent for its interesting structural ,valuable stratigraphic and paleontological record .Salt range is characterized by extensive anticlines folds, Synclines Folds ,and various types of Syncline fold and various types of Faults. It also important as source as a source of mineral e.g. Halite ,Gypsum, Coal, fire clay etc. The occurrence of these mineral is important in stratigraphic as well as paleontological point of view .That's why Salt range sequence of Pakistan has fascinated Geologist from all over the world due to its well preserved faunal assemblages .
The Salt range is mainly divided into two parts The area to the east of the River Indus "Main Salt Range" or "Cis Indus Salt Range "and the area to the west of river Indus is called Trans Indus Salt Range "
The Main salt ranges is further divided into three ranges
a) Eastern Salt Ranges i.e. khewrra Gorge .b) Central Salt Ranges i.e. Nammal Gorge.c) Western Salt Ranges i.e. Zaluch Gorges or Zaluch Nala .
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Stratigraphy of Salt Range
Eastern Salt Range is about 16km and its height about the sea level is 760Km .The Western Salt Range is widen westward to the width of about 32km with highest attitude of 1422m at Sakessar similar Salt Range is more wider than Eastern and Western Salt Range.
The Salt Range strikes almost East West and terminate at Kalabagh where the range is intersected by river Indus .Beyond the river Indus the range beak out into various ranges collectively referred as Tras-Indus range. The rock in the Salt ranges are generally folded and are typically marked by large and small scale faulting as well as local over thrusting with movement towards south .The sedimentary sequence ranges from Pre-Cambrian to the Eocene and recent age .It also marked by several unconformities
In our field we visit to above all three range i.e. Eastern ,Western and Central Salt range .In the Eastern salt range we study the Khewra Gorge ,while In the Central Salt range we study the Nammal Gorge and the Western Salt range we study the Zaluch Nala. We have studied the stratigraphy and detailed lithology of the various Formation exposed in the above said Gorge .
We also observed some the important mineral deposit e.g. Khewra Salt Mine, Coal deposit , Sulpher etc.
Stratigraphy Of the Salt RegionThe rocks of the Salt range stratigraphic unit ranges in the age from Pre-Cambrian to the Tertiary
age with the marked absence of Ordovician Silurian .Devonian and Carboniferous age throughout the region . In salt ranges the oldest Formation is of Precambrian age i.e. salt range and the youngest Formation is of Recent age Pleistocene i.e. Lei Conglomerate.
Locally a given stratigraphic rock sequence pinches out laterally to the point of vanishing e.g. Mesozoic sequence is well developed in the western salt range and Tras-Indus range and Triassic and Jurassic and perhaps all the cretaceous Formation are conspicuously absent in the most of Central and Eastern Salt range
An igneous intrusion of the younger age is also present in the Cambrian age rock called " Khewrite" or "Khewrra tap ".Several type of Unconformity are also present in the area which also include Para Unconformity ,i.e. Permian Triassic Boundary and Cretaceous Tertiary Boundary .Between the khussak and juttana there is erosonal Unconformity .
Permian is divided into Two groups
a. Nilawahan Group b. Zaluch Group
The Zaluch have three Formation .i.e.
I. Amb Formation or Lower Productus Limestone.II. Wargal Limestone or Middle Productus limestone.
III. Chhidru Formation or Upper Productus Limestone.
because all these have Productus fossil of brachiopods so it's called productus limestone.
Amb Formation
Amb does not exposed as a whole but upper part is exposed . The phosphatic shale represent the upper part of Amb Formation which is the last unit .
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Stratigraphy of Salt Range
Litholgy
Limestone and Phosphatic shale
Fossil
Brachiopods and Gastropods
Contact
amb have conformable contact with wargal Formation. Wargal limestone lithology it has 90% of limestone and have massive bed.
.
upper part of amb Formation
Wargal Formation
Lithology
Limestone, dolomite, dolomitic limestone ,sandy limestone because of terreginious environment
there is interconnected shale also in the upper part of Formation .thaths why it's can't called wargal limestone but it is known as wargal Formation.
The diagnostic features is Stylolites.
Stylolites
it is also called pressure dissolution structures .It follow the Rikies principle.
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Stratigraphy of Salt Range
stated that "Greater pressure causes dissolution and low pressure causes precipitation .Vein and stylolites form by this way .this is a carbonate rock diagnostic features . It is a secondary sedimentary structure .
Contact
upper contact is gradational with Chhidru and lower contact is conformable with Amb. if wargal have shale than it mean that we goes towards the chiddru.
Stylolite (Secondry sedimentry structure)
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Stratigraphy of Salt Range
Wargal Limestone
Chhidru Formation
Lithology
Friable Sand stone,Shale ,limestone ,sandy limestone, shale,Calcareous sand stone deposition control by sea level rise fall and sea level rise . Sea level fall :Terreginious influx sandstone Sea level Rise :Limestone and represent Marine environment. If sea level rise and fall both than there is a mixture of lithology . Age is Permian.
Chhidru Formation
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Stratigraphy of Salt Range
P-T Boundary ( Permian Triassic boundary
The abrupt change in fossil is called Para conformity i.e. Ammonides due to thus here is Unconformity between Chhidru and Mianwali Formation.
Musa khail Groupa) Mian wali Formation
Mianwali have three big members which is under;
1. Kathiwai Member
lithology is silty Dolomite
2.Mithiwai Member
There lithology is shale and sandstone .the sandstone pitches show resistance.
3.Narmia member
The lithology is shale and dolomite.
Age is Triassic .
kathwai Member of Mianwali group
Tredian Formation
The lithology of Tredian is 90 to 95% Sandstone. It has two member
I. Landa Member II. kathkiara Member
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Stratigraphy of Salt Range
The primary sedimentary structures are preserved Lithology is Shale,Siltsstoone and sandstone . direction is unidirectional. In case of water flow at beaches than thin lamination is preserved . Convolute structures . Direct depth with Kingriali Formation. Age is Triassic.
Tredian Formation
Kingriali Formation
Lithology :Dolomite ,dolomitic limestone ,calcareous dolomite ,
Contact :Direct contact with Datta sandstone .
Age is Triassic .
Tredian Formation
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Stratigraphy of Salt Range
Surghar GroupI. Datta Formation
II. shinawari FormationIII. samanasuk FormationIV. Chichali FormationV. Lamshiwal Formation
VI. Kawagarh Formation
Except Datta all are not exposed in salt ranges
Datta Sandstone
In literature datta is also called Petroleum system . the lithology is sandstone ,coal seam and Oil seep because for petroleum system need three
rocks i.e. the source rock .The resource rock ,and cap rocks . Datta have capability of production ,permeability and it covers also . It have sulpher seems also ( yellowish brown). The environment is deltaic .
Economic Importance
silica sand is used economically in the form of silica gel and their production is take place from Karak area
Silica sand is also used in ceramics .
Archosic Sanfd Stone
It is a course sandstone in which phosphorus is dominant is called Archosic Sand stone.
Contact: the lower is conformable with kingriali but upper is not conformable.
Datta Formation
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Stratigraphy of Salt Range
Makarwal Groupit contain three Formation.
I. Hungu Sandstone II. Lockhart Formation
III. Patala Formation
Hungu sandstone
It has compacted and quartzite in nature sandstone near to dolmite in hardness .In salt ranges 10 to 12 meter exposed and direct contact with Lockhart Formation .
Age is Paleocene .
Lockhart Limestone
Lithology is Nodular limestone . Basically Nodule is two types; Chart Nodule, carbonate Nodule. and this is carbonate nodule . In samana ranges it is very exposed. Age is Paleocene .
Noduler Limestone (Lockhart Formation)
Patala Formation
Lithology is Shale ,Limestone and impure limestone which is also called marl. Shale is eroded and look like clay . limestone pitches show resistance to erosion . Eocene is the last succession of carbonate rocks in Pakistan.
Contact :the lower is conformable with Lockhart limestone and the upper is also conformable with Nammal Formation.
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Stratigraphy of Salt Range
Patala Formation
Cherat Groupit contain three Formation i.e. Nammal , Sakesar,and chorgali Formation. The chorgali is missing in salt ranges.
1.Nammal Formation
the lithology is 70 to 80% clay stone and limestone .
The lower contact is conformable with Sakessar Formation
2.Sakessar Formation
the lithology is similar to Lockhart nodular limestone but not much like Lockhart.
3.Chorgali Formation
It is missing in salt ranges
Travertine Deposit
When hot water dissolved the CaCO3 and leave pores in limestone .It occurs in subsurface because it is caused by hot spring of ground water .The magmatic fluid make water hot which become less dense and then move upward and dissolve CacO3 and make the Limestone porous .this deposition is called travertine deposit.
This deposition dedicated hot spring called geasour which is most common in Chitral.
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Stratigraphy of Salt Range
Travertine Deposit
Stop No 2nd
Western salt range
Zaluch nala
Mixed lithology of different particles cementing together called conglomerate .the conglomerate which have fan shape called fanglomerate .
A fan shaped alluvial deposit formed by a stream where its velocity is abruptly decrease as at the mouth of a ravine or at the foot of mountain
when many alluvial fan combined in one place than its called Bajada.It is a coalescence of different alluvial fan .In zaluch nala there is too much alluvial fan .
Different cementing particles ,silica ,clast but mostly sand fine sand and as well as coarse sand.
it is well compacted .
Nialwahan group is exposed in zaluch nala which is contain four Formation .i.e.
I. Tobra Formation II. Dondot Formation
III. Warccha SandstoneIV. Sardi Formation
In zaluch nala Dondot is not exposed but exposed in the Dondot village.
Tobra Formation
Lithology :Conglomerate ,Sandstone ,Silty sandstone, and Shale.
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Stratigraphy of Salt Range
Three different episodic deposition environment
a. Pure glacial environment and is known Tellite deposit.b. Glacial and marine environment is known as galcial fluvial facie or also called complex deposit.c. Pure river system environment is known as fluvial environment.
Special features
Tobra Conglomerate have any type of rock fragment . Igneous is in the form of granite which is in pink color This granite protolith is called Nagar parker granite . The origin of Nagar Parker granite is Sargodha High or jekababad High . This conglomerate also contain metamorphic rocks this facie is called glacio fluvial facie Because of glacial fluvial environment .
Fossil
Pollen and spores and ganomopteris .
Faceted Surface
A big transport agency(Glacier), due to over burden the load which is transported by glacier break and formed a smooth surface called Faceted surface. It represent the glacier environment .
Contact: the upper contact is conformable with warccha sand stone and lower is unconformable .
Gravic Sandstone
The sandstone which have Nagar Parker granite or Quartz ,feldspar are called gravic sandstone .
or The sandstone which contain more than 15% clay is called gravic Sandstone.
Age is Permian.
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Stratigraphy of Salt Range
Tobra Formation
Sardai Formation
It is also called Sardai clay or lavender clay or Varigiated clay. The difference between clay and shale is that shale have phyisility (thin layer) while clay doesn't
have . There is no importance economically. There is sharp contact with Amb .
Zaluch Group
Amb Formation
Lithology
Sandy limestone ,limestone ,
Fossil
Fucilina are first ever reported in Amb Formation. Fucilina is Eocene time index fossil. Fucilina look like rice .It also have Burrows vertical as well horizontal
Tobra Warccha Tobra Sardi Amb
Method Of Determination Of Strike and Dip
The directional aspects of tilted bedding planes ,fold axes ,faults ,and other geologic structures can be completely described using two types of measurement :Strike and dip
Strike
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Stratigraphy of Salt Range
(Illustrated by line s-t below) The compass direction of a line marking the intersection of an inclined plane with a horizontal plane Such as the Earth's surface
We will measure strike using in ordinary compass with a bubble leveling device attached .Many compass direction system are possible ,but we will be using the "azimuthal system" Indicated. Indicated below
The direction for finding strike are:
1) Place the side edge of the compass against the bedding plane.
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Stratigraphy of Salt Range
2) Use the bull's eyes leveling bubble to make the compass horizontal (while maintaining step 1 above)
3) The Strike of the bedding plane is indicated by the needle direction .For consistency ,record the lower value of the two supplementary angle (for example if the needle point is to 120 degrees and 240 degrees ,you should record 120 degrees ).
Dip
(line d-p above) Dip is the maximum angle between the inclined plane and the horizontal plane .Dip is always perpendicular to strike ,and has both a compass direction and in angle.
The direction for finding dip are
1) Determine the dip direction .This is always perpendicular to the strike direction .2) Use the inclinometer to measure the amount of dip in degrees (a plane lying flat along
the horizontal as zero dip ).
Reporting Strike and Dip on a Map
Geologist frequently report need to record strike and dip on a map (bird's eye view ).The procedure is quite simple.
1) Draw the strike line with the correct orientation (0-360 degrees )2) Draw the dip line perpendiculer to the strike line ,and in the correct direction of the dip .Ask
yourself ....which direction would your head point if you were standing on the inclined plane ?3) Record the amount of dip (0-90 degrees) at the tip of the dip line .
4)The following notation are used to record the durection of anticline and syncline fold axes .
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Stratigraphy of Salt Range
The Brunton Compass
In real life ,geologist use an instrument called a Brunton Compass to measure strike and dip .This device contain a compass ,leveling bubble and inclinometer all built into one unit this versatile device can be used as a transit for the purpose of triangulation.
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Stratigraphy of Salt Range
Day No 3rd
Eastern Salt Ranges
Stop No 1st
Our task on 3rd day was to study the rocks of Precambrian and Cambrian .Which is divided into two major groups i.e. the Salt range and jehlum Group respectively.
Precambrian age rocks is Salt range Formation.
it is divided into three major member on base of lithology.
I. Sahiwal marl memberII. bandarkhas Gypsum member
III. billian walan salt member
Sahiwal marl member
Salt is in the form form of seam and have dolomitic layers. Deposition is in different environment . Marl of this member is two type Dull red marl which deposition is legonal or evaporated environment. Legonal is the cut off body of water from ocean and formed a setup called legon. In legonal water when influx diminished and from stand water the water evaporated
and salt and gypsum settle down precipitate in the form of deposition. Bright red marl member the environment is oxidation reduction . The environment is marine that why have dolomite.
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Stratigraphy of Salt Range
Bright and Dull Red Marl Members
Banderkhas gypsum member
Gypsum is greenish grey white . there is a mine for extracting of gypsum. Gypsum have very economic importance i.e. Used in cement In different powder etc.. It is also Used as Plaster of Paris.
Billianwalan Salt member
Mining occurred in this member. it has pure salt ,khewrite and gypsum. Age is Precambrian.
Contact
Lower contact: With kirrana hills it is a subsurface basement rocks which is older than salt range Precambrian and called Eucambrian.
Upper contact: Conformable with khewrra sandstone .
Jehlum groups
Due to type locality of jehlum district its called jehlum group. Age is Cambrian. it has four Formation namely :
I. Khewrra SandstoneII. Khussak Formation
III. Juttana FormationIV. Baghanwalan Formation
Khewrra Sandstone
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Stratigraphy of Salt Range
Khewrra sandstone is also called Purple sandstone. it have interconnected shale . It has two type of sandstone. Thin lamination sandstone. Medium bedded sandstone. Environment is fluvial . Due to fluvial environment there is no carbonate succession . There is different sedimentary structure i.e. Burrows ,Ripple marks ,Ball and pillow and cross
bedding . These structures is the diagnostic features of flu Fluvial environment. Khewrra sandstone bedding are pinch out and it represent the flow of river decrease or
represent the stop clastic deposition.
Khewra Sandstone
Ripple Marks
A system of parallel wavy ridges and furrows left on sand ,mud,or rock by the action of water or mind.
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Stratigraphy of Salt Range
Ripple marks
Ball and pillow
A sedimentary structure occurring on the base of some sandstone which are inter bedded with mudstones and characterized by globular protrusion and isolated pillows of sandstone found in the the underlying mudstone .these structure form by the differential settling of the unconsolidated sand into less dense mud below.
Ball and Pillow Structure
Cross bedding
Sedimentary are normally deposited horizontally layers .Even when folded or tilted by faulting the originally horizontal layering is obvious .But the very fine layers that are at an angle to the original layers or bedding .these tilted layers contain within larger layers are termed as cross bedding
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Stratigraphy of Salt Range
Contact
Lower: Conformable with Salt range Formation.
Upper: Erosional bed of conglomerate with Khussak .
Khewra sandstone
Khussak Formation
The deposition is shelfal environment and are clastic deposition . it has glauconitic mineral . In old literature it is also called glauconitic sandstone. it is very loose . Khussak Formation have interconnected shale is common . Contact is conglomerate boulder show erosinal unconformity .
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Stratigraphy of Salt Range
Khussak Formation
Juttana Formation
it lithology is sandy dolomite and Pure Dolomite. The lower portion is sandy portion and therefore it is soft . The upper part is Massive pure dolomite . Dolomite have two type i.e. primary and secondary dolomite . If Dolomite contain 90 to 95% dolomite it's called Dolostone.
Primary Dolomite
It precipitate directly . It contain 90 to 95% CaCO3.
It have algal stromatolite.
Secondary Dolomite
It is much more important in respect of petroleum because it act as reservoirs and also have permeability.
it is very important than primary dolomite. The digenetic change effect reservoirs . This effect maybe positive to enhance hydrocarbon in the form of porosity and permeability or
negative effect to freezes the hydrocarbon. In calcite there is 100% calcium. In calcite 50% of the calcium is replaced by Magnesium to form dolomite. Secondary dolomite have a recourse of limestone .
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Stratigraphy of Salt Range
Juttana lower Part
Algal Stromatolite
algae is a marine plant organism .It needs sunlight for photosynthesis to prepared their food .
It comes to shallow water at day time for sunlight and at night it goes to bottom .Above the mud deposition take place at day time its try to overcome on mud but its fail and the algae preserved in the mud in the form of wave shape.
Baghanwalan Formation
Lithology
Siltstone ,sandy siltstone ,sandstone and shale . The diagnostic feature is Salt psuedomorphs. Age is Cambrian. The lower contact is conformable with Khussak Formation and upper is unconformable . The deposition environment is legonal. There is a major unconformity between Permian and Cambrian age.
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Stratigraphy of Salt Range
Baghanwalan Formation
Reference Stratigraphy Of Pakistan By Ibrahim Shah. Field Report Of Salt range by Ahmad Ghani
o Peshhwer University www.pitt.edu/~cejones/geolmages. www.encyclopedia.com https:en.m.wikipedia.org http://www.geologyclass.org/structures_concepts.htm
Credits
With the Grace of Almighty Allah (The most merciful and beneficent )I have completed my this report of Salt Range Field .This all credits goes to my dear Parents ,respected Teachers and fellows specially Arshad Ayub and Abrar Ali who always helped me in their prayers ,guided me through their best and gave me a back up while doing this tough job.
I want to thank them all.
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