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The Lower Jurassic Datta Formation, western Salt Range, Pakistan, comprises three facies associations: (1) channel belt facies association (CBFA), (2) channel margin, and overbank facies association (CMOFA), and (3) lagoonal facies association (LFA). A cyclic fining-upward trend in the succession is represented by basal quartzose conglomerate/pebbly sandstone, through coarse to fine quartzose sandstone to siltstone and shales/claystone, which contains some carbonate accumulation. Two prominent depositional sequences are recognized in the Datta Formation with the lower high and upper low magnitude cycles. The Datta Formation thus represents a thick sedimentary succession and in the study area, i.e., western Salt Range, mainly channel belt, flood plain and/or delta top facies are exposed. The palaeocurrent analysis shows that the source area with acidic plutonic rocks laid to S-SE in the Indian shield, aravalies or older sedimentary rocks of the Indus Basin (i.e., Khewra, Tobra and Warchha formations). A tentative stratigraphic correlation of the Datta Formation with the lower Jurassic Lathi Formation, India invites further work in parts of India, which will elaborate the extent of the Datta Formation in the Greater Indian peninsula and develop palaeogeographic setting for this Lower Jurassic deltaic rock unit.

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Human biomonitoring is a well-recognized tool for estimating the exposure of humans to environmental pollutants. However, heavy metals’ pollution from anthropogenic origin is a cause for concern because of its potential accumulation in the environment and living organisms, leading to long-term toxic effects. This study was aimed to assess the concentrations of cadmium (Cd), chromium (Cr), lead (Pb), copper (Cu), nickel (Ni), cobalt (Co), manganese (Mn), iron (Fe), and zinc (Zn) in human biological samples (urine, whole blood, hair, and nails) and antioxidant response in blood samples from 48 individuals exposed to heavy metals and to compare them with different age classes and sites. The results indicated that there were metal-specific differences in concentration in exposure groups among the studied sites. The concentration of heavy metals in blood samples showed the following order : Pb > Cd > Ni > Co > Cr. In urine samples, the order was Cu > Pb > Cr > Ni > Co > Cd; in nails samples, the order was Pb > Ni > Cr > Co > Cd > Mn; and in hair samples, the trend was Pb > Ni > Cr > Mn > Cd > Co. A significant ( p > 0.05) decrease in antioxidants enzymes activity was observed with increase in heavy metals concentrations. This is the first study reporting biological evidence of altered toxic metals’ concentration in humans in Lahore, Pakistan, due to environmental exposure. Further research, including risk analysis studies, food chain contamination, and epidemiological and clinical investigations, are needed to assess optimal levels for dietary exposure in the study area and associated adverse health outcomes.

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The Pleistocene represents the youngest period of repeated widespread glaciation and interglacial intervals of both hemispheres. The Pleistocene-Holocene siliciclastics of the Peshawar Basin preserve a significant terrestrial record of palaeoclimatic fluctuations during this glacial time interval in northwest Pakistan at latitudes of 33-35°N. The sedimentological evidences indicate that the lower part of the stratal package consists of floodplain clay cycles overlain by lacustrine-glaciofluvial rhythmites, that are followed by loess deposits and finally recent floodplain clays. The geochemical proxies demonstrate an overall cold-arid climate with very low intensity of chemical weathering, whereas the clay mineralogy and related indices suggest intensifying physical erosion. The chemical index of alteration (CIA) reflects comparatively slightly higher (but still very low) intensity of chemical weathering for the lowermost part of the succession and uppermost loess deposits. The illite-rich clay mineralogy of these two lithofacies associations also indicates the prevailing cold-arid palaeoclimate. The low CIA and smectite-rich clay mineralogy of the rhythmites, on the other hand, reflect deposition in poorly drained lakes. Multiple evidences for break-out floods and the presence of ice-rafted debris (IRD) within the rhythmites provide conclusive evidences for ice damming in the Peshawar Basin and drainage blockage due to the uplift of the Attock-Cherat Range. The floodplain clays indicate deposition in an interglacial semiarid-semihumid palaeoclimate preceding the Shanoz stage glaciation. The rhythmites correlate with the Shanoz, Yunz, and Borit Jheel glacial stages. The loess deposits indicate aeolian deposition in a cold, periglacial environment spanning over the late glacial maximum (LGM) interval.

The Salt Range, in Pakistan, preserves an insightful sedimentary record of passive margin dynamics along the NW margin of the Indian Plate during the Mesozoic. This study develops provenance analyses of the Upper Triassic (Kingriali Formation) to Lower Jurassic (Datta Formation) siliciclastics from the Salt and Trans Indus ranges based on outcrop analysis, petrography, bulk sediment elemental geochemistry, and heavy-mineral data. The sandstones are texturally and compositionally mature quartz arenites and the conglomerates are quartz rich oligomictic conglomerates. Geochemical proxies support sediment derivation from acidic sources and deposition under a passive margin setting. The transparent heavy mineral suite consists of zircon, tourmaline, and rutile (ZTR) with minor staurolite in the Triassic strata that diminishes in the Jurassic strata. Together, these data indicate that the sediments were supplied by erosion of the older siliciclastics of the eastern Salt Range and adjoining areas of the Indian Plate. The proportion of recycled component exceeds the previous literature estimates for direct sediment derivation from the Indian Shield. A possible increase in detritus supply from the Salt Range itself indicates notably different conditions of sediment generation, during the Triassic–Jurassic transition. The present results suggest that, during the Triassic–Jurassic transition in the Salt Range, direct sediment supply from the Indian Shield was probably reduced and the Triassic and older siliciclastics were exhumed on an elevated passive margin and reworked by a locally established fluvio-deltaic system. The sediment transport had a north-northwestward trend parallel to the northwestern Tethyan margin of the Indian Plate and normal to its opening axis. During the Late Triassic, hot and arid hot-house palaeoclimate prevailed in the area that gave way to a hot and humid greenhouse palaeoclimate across the Triassic–Jurassic Boundary. Sedimentological similarity between the Salt Range succession and the Neo-Tethyan succession exposed to the east on the northern Indian passive Neo-Tethyan margin suggests a possible westward extension of this margin.

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