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The Quetta and surrounding areas are part of the collision zone between the Indian and Eurasian plates, named as Kirthar and Sulaiman Fold-Thrust belts. The collision is accommodated by folding, thrusting and the Nushki-Chaman Transform Fault System. Detailed high-resolution (scale 1:50,000) mapping and structural analyses were carried out using modern remote-sensing techniques of the ArcGIS to understand mutual relationships of the structural patterns and geometries, and the regional and local stress patterns in the study area. Fieldwork was carried out to acquire the stratigraphic, structural and geomorphological data, using topographic maps and satellite images as base maps in order to plot additional information and further incorporate them in the GIS-based map. Balanced structural cross-sections were also prepared along the selected lines using ArcGIS techniques. Based on new mapping, the understudy area has been subdivided into five distinct structural domains. These domains are classified as; Domain I: broad syncline intervened by a narrow anticline; Domain II: upright folds and thrusts; Domain III: tight, over-turned thrust zone; Domain IV: flysch and molasse successions of Paleocene-Holocene age; and Domain V: suture belt (ophiolites) and associated mélanges and sediments. [ABSTRACT FROM AUTHOR]

Sandstones of the Triassic through Pliocene successions of the western Sulaiman Fold-Thrust Belt (SFTB), Pakistan, were studied, by polarizing microscope and using point-counting techniques, to determine systematic variations in detrital modes. The sandstones in the study area are categorized into pre- and postcollisional sandstone assemblages. The precollisional assemblage was deposited before the onset of collision of India with Eurasia (starting Late Cretaceous-Early Paleocene) and subcategorized as WulgaiMughal Kot, Bibai and Pab subassemblages. The postcollisional assemblage was deposited after the onset of collision and categorized as Ghazij and Urak subassemblages. The Wulgai-Mughal Kot subassemblage mostly comprises of highly quartzose sandstones of the Triassic Wulgai and Upper Cretaceous Mughal Kot formations. The Pab subassemblage consists of quartzose sandstone, with additional limestone and calcareous fossil fragments, of the Upper Cretaceous Pab Formation. Its detrital mode is craton interior, i.e. the crystalline basement of the Indian continent. The Bibai subassemblage is comprised of lithic arenites of the Middle-Upper Cretaceous Bibai Formation (Bibai Group) and is predominantly composed of mafic volcanic fragments, having a detrital mode of a magmatic arc. The Ghazij subassemblage, of the postcollisional assemblage, is comprised of lithic arenites of the Eocene Ghazij Formation, sourced mostly from a volcano-sedimentary terrain, derived from a recycled/transitional recycled orogen, indicating the initial stage of uplift (and sedimentation) of the successions including ophiolites of the suture belt. The Urak subassemblage is comprised of lithic arenites of the Miocene Uzda Pusha and Pliocene Shin Matai formations, and composed of a variety of sedimentary lithic fragments with ample quantities of quartz and feldspar. The detrital modes of this subassemblage indicate a recycle orogen derived from the collision orogen of the SFTB. The shift, in composition, provenance and detrital modes, from the pre- to postcollisional assemblages indicates beginning of the uplift and sedimentation of the older successions, including the hot spot-related volcanics of the Bibai Group. This study supports the notion that collision of the India with Eurasia initiated soon after the Late Cretaceous, resulting in the emergence of the older successions of the SFTB, reaching its culmination in Pliocene. [ABSTRACT FROM AUTHOR]

The Oligocene and Early Miocene Khojak Formation represent a deltaic to sub-marine fan succession in the Khojak-Pishin flysch belt within the Katawaz basin of Pakistan. The sandstone within this succession is dominated by sedimentary and metamorphic clasts and has been derived from recycled orogeny. The higher SiO2/Al2O3 atios (4.0) show moderately mature nature of the sandstone. The weathering indices such as 2 2 3 Chemical Index of Alteration (CIA; 76.69), Chemical Index of Weathering (CIW; 86.79), Chemical Proxy of Alteration (CPA; 92.33) and Index of Chemical Variability (ICV; 16.83) suggest moderate to intense weathering at the source terrain. The high Th/U values (5.25) as compared to Upper Continental Crust (UCC; 3.82) also support the enhanced weathering of the source area. Trace elements such as Zr, Nb, Y, Th and U are slightly enriched compared to UCC suggest the dominantly felsic sources for the formation. High enrichment of Cr, Ni and V, and moderate ratios of Cr/Ni (1.72) and Cr/V (1.83) indicate substantial contributions from ultramafic sources while fairly high percentages of Fe2O3 (7.66) and MgO (3.90) as compared to UCC (5.03% 2 3 and 2.20%, respectively) hints toward mafic sources. The tectonic setting for the Khojak sandstone is considered as continental arc to active continental margin. This study supports the notion that the western Himalayan orogenic belt was shedding largely felsic detritus to Katawaz basin through proto-Indus River, while mafic and ultramafic detritus were being fed by distant Kohistan Island Arc and en-route Waziristan, Zhob and Muslim Bagh Ophiolite and associated mélanges. The sediment dispersal towards south-southwest was controlled by Chaman-Nushki transform fault system. [ABSTRACT FROM AUTHOR]

The Neogene siliciclastic succession of the Pishin Belt comprises the newly proposed Middle to Upper Miocene Dasht Murgha group, Miocene-Pliocene Malthanai formation and Pleistocene Bostan Formation. Sandstones of the succession have been classified as lithic arenites and their detrital modes indicate derivation of material from the Pre-Miocene sedimentary and meta-sedimentary terrains of the Pishin Belt. X-ray diffraction (XRD) analyses indicate that clay minerals in various mudstones and sandstone samples are identical and detrital in nature and include smectite, chlorite, illite, serpentine and kaolinite. Smectite and chlorite are most probably derived from the metavolcanic and mafic volcanic rocks, respectively. Presence of serpentine in samples of the Bostan Formation indicates altered ultramafic rocks as one of the source terrains. Illite is probably recycled from the older sedimentary and metasedimentary successions. The source of kaolinite seems to be pedogenic or lateritic. The clay minerals assemblage in mudstones and sandstones of the Dasht Murgha group, Malthanai formation and Bostan formation appears to have been derived from the nearby-exposed Pre-Miocence mafic/ultramafic rocks of the Cretaceous Muslim Bagh-Zhob Ophiolite and argillites of the Eocene Nisai and Oligocene Khojak formations of the Pishin Belt. The Triassic-Jurassic succession, of the Wulgai and Loralai formations of the adjacent Sulaiman Fold-Thrust Belt, is also believed to have provided some material, however in subordinate amount. [ABSTRACT FROM AUTHOR]

An isolated outcrop, comprising a 300 m thick succession of the Late Cretaceous-Palaeocene Ispikan group, is exposed as a thrust-bound inlier within the Oligocene-Miocene succession of the Panjgur Formation, 3 km to the northeast of the Ispikan village, in south-western Makran, Pakistan. The group is divisible into two lithostratigraphic units; 1) the Late Cretaceous Ispikan group in lower part; comprising mudstone, shale, siltstone and sandstone; and 2) Palaeocene Ispikan Conglomerate in upper part; comprising very coarse pebbly sandstone and conglomerate. The Ispikan conglomerate is composed of pebbles of a variety of igneous, sedimentary and metamorphic rocks. Sandstone also dominantly comprises igneous and metamorphic rock fragments. Detrital modes of the sandstone suggest a recycled orogenic source, most probably the Himalayan- Karakorum-Hindukush collision orogen. The group comprises 9 distinct facies, organized as 2 facies associations including the inner-fan channel facies association and the basin-plain facies association, which were parts of the earliest fan system of the Khojak-Panjgur submarine fan complex. The petrology and provenance of the Ispikan group resemble with those of the surrounding younger submarine fan succession of the Oligocene-Miocene Panjgur Formation, however, its stratigraphic and palaeogeographic relationship with the surrounding succession still remains speculative needing further investigation. [ABSTRACT FROM AUTHOR]

Groundwater is a major source of water supply for domestic and irrigation uses in semiarid, remote but rapidly developing Kilasaifullah district part of Zhob River Basin, located at Pakistan-Afghanistan Border. Zhob River is among few major rivers of perennial nature in Balochistan, which flows from WSW to ENE and falls in Gomal River, a tributary of Indus River. Keeping in view the important geopolitical position and rapid development of the region, this study is primarily focused on groundwater chemistry for contamination sources as well as agriculture development. Water samples from open and tube wells are analyzed and calculated for electrical conductivity (EC), total dissolved solids (TDS), turbidity, pH, K+, Na+, Ca2+, Mg2+, HCO [ABSTRACT FROM AUTHOR]

The siliciclastic Neogene succession of the Pishin Belt comprises the newly proposed Miocene Dasht Murgha Group, Miocene-Pliocene Malthanai Formation and Pleistocene Bostan Formation which were deposited as fluvial succession in the foreland setup. Thin section studies and modal analyses revealed that sandstones of the Dasht Murgha Group and Malthanai Formation are lithic arenite and show recycled and transitional recycled orogenic source. Sandstone detritus has been derived mainly from the sedimentary and metamorphic terrains, sedimentary rocks being a more pronounced source terrain than the metamorphic rocks, particularly in the Malthanai Formation, however, the volcanic terrain has also provided its detritus but in minor proportion. Composition of conglomerate of the Dasht Murgha Group, shows that the Eocene Nisai Group and Oligocene Khojak Formation are the main source terrains, whereas, the Jurassic Loralai Formation and Muslim Bagh-Zhob ophiolite are the subordinate source terrains. Conglomerate of the Malthanai Formation shows similar composition with additional contribution from the Dasht Murgha Group. Conglomerate of the Bostan Formation shows that its detritus has mainly been derived from the Nisai Formation, Khojak Formation, Muslim Bagh-Zhob ophiolite, as well as Dasht Murgha Group and Malthanai Formation. Detritus of the Triassic Wulgai Formation, Jurassic Loralai Formation and Cretaceous Parh Limestone has also contributed in subordinate amount. Detrital modes of the sandstones and petrology of the conglomerates show that the detritus for the Neogene succession has mainly been derived from the Pre-Miocene sedimentary and meta- sedimentary terrains of the Pishin Belt from the west, which include Eocene Nisai Formation and Oligocene Khojak Formation; and Sulaiman Belt from the east, which include Triassic Wulgai Formation, Jurassic Loralai Formation and Cretaceous Parh Limestone. Also mafic and ultramafic detritus has been provided by the Muslim Bagh and Zhob ophiolite exposed along the western margin of the Indian Plate. [ABSTRACT FROM AUTHOR]

The Jurassic Loralai Formation is part of the Sulaiman Fold-Thrust Belt, Pakistan, which is predominantly composed of limestone with minor shale, marl and sandstone. Sandstone succession has been discovered in the Feroz-e-Kan and Ziarat Morh sections, southwest of the town of Muslim Bagh. Geochemical analyses of these sandstones were carried out in order to classify and understand the source area weathering and provenance. Geochemically, the sandstone is classified as litharenite. Compared to the Upper Continental Crust (UCC), the sandstones are depleted in SiO2, and Al2O3, and enriched in K2O and MgO. The Chemical Index of Alteration (CIA) (range: 71.08-83.68) reflects moderate weathering of the source area, and the Chemical Index of Weathering (CIW) (range: 73.87-94.56) indicates high level of weathering. Trace elements analyses indicate depletion of the Large-ion Lithophile elements (LILE), as compared to the UCC. Enrichment of the Zr in the sandstone samples indicates derivation from the zircon-rich source rocks. The Ferromagnesian Trace Elements (FTE), however, show depletion, which suggest very minor input from the mafic and ultramafic source. Plots of the sandstone samples in the tectonic discrimination diagrams indicate derivation from the passive margin setting having quartzose sedimentary and intermediate igneous provenance. We propose that igneous and metamorphic rocks were the major contributors, which were recycled. Therefore, terrigenous detritus of the sandstone has been derived from the Indian Craton, situated to the east-southeast of the study area of the Sulaiman Fold-Thrust Belt. [ABSTRACT FROM AUTHOR]

The Late Cretaceous, Moghal Kot Formation is well exposed in the Sulaiman Fold-belt of western Pakistan. It is 50-650m thick and is dominated by mudstones, shales and marls with subordinate thin to medium-bedded quartzose sandstones, deposited on the western continental margin of the Indian Plate during the Late Cretaceous (Late Campanian to Maastrichtian). Detailed sedimentary logs of five measured section in the study area, provide data for facies analysis, dispersal patterns and environmental interpretations. Four facies, recognized within the Moghal Kot Formation include; Slump, and debris flow facies, Laminated mudstones facies, Bioturbated mudstones/shales, and marls facies, Lenticular, and erosive sandstones facies and laterally continuous thin-bedded sandstones facies. The facies can be grouped into two main facies associations; (slope facies association and lower shelf delta /prodelta facies association). All of these facies were deposited by turbidity flows. The vertical and lateral distribution of facies within the Late Cretaceous succession (Moghal Kot, Fort Munro and Pab formations) reveals overall upwards-shallowing and also demonstrates a transition from fluvio-deltaic, inner shelf to fault controlled slope setting. The abundance of slumped units in the lower part of the Moghal Kot Formation suggests that the slope was unstable and active (more likely fault- controlled). Palaeoflow was predominantly towards the W and NW from the uplifted Indian basement to the east. [ABSTRACT FROM AUTHOR]