Abstract Rivers and river-borne deposits have always been a major attraction for hominins as an important source of sustenance and settlements. Hence, fluvial deposits have long been an important source of evidence for early human occupation throughout the Old World. Apart from being an important palaeoclimatic marker, fluvial sequences have provided archaeologists with frameworks for correlation, along with Palaeolithic markers discovered within them. Moreover, given the influx of sediments eroded and deposited by Indian rivers, these could have acted as a centre of hominin activities. Palaeolithic research in India has been concentrated around some of its major river valleys, which have yielded a rich record of hominin occupation. So far, 305 Palaeolithic sites have been reported from a gravel context throughout the country, yielding Lower to Upper Palaeolithic, Mesolithic and Neolithic evidence. However, most of the derived evidence is secondary deposits and stands contested based on its contextuality. Nevertheless, its importance as a source of information about hominin activity cannot be underestimated. This review presents a provisional synthesis of all of the Indian Palaeolithic sites reported from gravel contexts, thereby presenting scope for future multidisciplinary research at these localities.

Abstract In this paper the authors review various applications of analysing fabric in granites from Indian cratons using anisotropy of magnetic susceptibility (AMS). First the general importance of AMS in identifying the internal fabric in massive granitoids devoid of visible foliations/lineations is highlighted. Subsequently, three important applications of AMS in granitoids are discussed. (a) The case of Godhra Granite (southern parts of the Aravalli Mountain Belt) is presented as an example of the robustness of AMS in working out the time relationship between emplacement/fabric development and regional deformation by integrating field, microstructural and magnetic data. (b) AMS orientation data from Chakradharpur Granitoid (eastern India) are compared with field-based information from the vicinity of the Singhbhum Shear Zone to highlight the use of AMS in kinematic analysis and vorticity quantification of syntectonic granitoids. (c) Magnetic fabric orientations from the Mulgund Granite (Dharwar Craton) are presented to document the application of AMS in recognizing superposed deformation in granitoids. Moreover, AMS data from Mulgund Granite are also compared with data from another pluton of similar age ( c. 2.5 Ga) from the Dharwar Craton (Koppal Granitoid; syenitic composition). This highlights the use of AMS from granitoids of similar absolute ages in constraining the age of regional superposed deformation.

Abstract Reconstructing the stratigraphic architecture of deposits prior to Cenozoic Himalayan uplift is critical for unravelling the structural, metamorphic, depositional and erosional history of the orogen. The nature and distribution of Proterozoic and lower Paleozoic strata have helped elucidate the relationship between lithotectonic zones, as well as the geometries of major bounding faults. Stratigraphic and geochronological work has revealed a uniform and widespread pattern of Paleoproterozoic strata >1.6 Ga that are unconformably overlain by <1.1 Ga rocks. The overlying Neoproterozoic strata record marine sedimentation, including a Cryogenian diamictite, a well-developed carbonate platform succession and condensed fossiliferous Precambrian–Cambrian boundary strata. Palaeontological study of Cambrian units permits correlation from the Indian craton through three Himalayan lithotectonic zones to a precision of within a few million years. Detailed sedimentological and stratigraphic analysis shows the differentiation of a proximal realm of relatively condensed, nearshore, evaporite-rich units to the south and a distal realm of thick, deltaic deposits to the north. Thus, Neoproterozoic and Cambrian strata blanketed the northern Indian craton with an extensive, northward-deepening, succession. Today, these rocks are absent from parts of the inner Lesser Himalaya, and the uplift and erosion of these proximal facies explains a marked change in global seawater isotopic chemistry at 16 Ma.

ABSTRACT The Barmer Basin of northwest India is a failed intracontinental rift that has become an established prolific hydrocarbon province in the last decade. Primary source rocks in the basin are the diatomites and interbedded lacustrine shales of the Paleocene Eocene Barmer Hill and Dharvi Dungar formations, although subordinate lacustrine shales in Lower Cretaceous sediments beneath the main rift basin are also high-quality source rocks. Synrift deposition commenced in the Paleocene and peaked in the Eocene, with Barmer Hill Formation shales maturing as early as 55 Ma. Generation continued across the basin through to the early Miocene. Kinetic variations in the Barmer Hill Formation source rock enabled the northern prolific type I lacustrine facies algal kerogen to mature at lower temperatures and generate more oil than the leaner but more deeply buried, deep water southern facies type III land plant kerogen equivalent. Migration modeling indicates that cross-fault juxtaposition of Paleocene and Lower Cretaceous reservoirs against downthrown mature source rocks is sufficient to charge all the known giant oilfields in the northern part of the basin. Accumulations in the shallower Dharvi Dungar and Thumbli formations in the central and southern parts of the basin require longer distance vertical and lateral migration from the mature Barmer Hill Formation through thick shale sequences, via fault linkages, fill and spill migration, and top-seal leakage. Post-Miocene, Himalayan-related collision inverted and tilted the northern part of the Barmer Basin, terminating generation in this area, while the southern basin kitchens continued subsiding and expelling hydrocarbons. Extensive residual oil shows attest to widespread, large-scale re-migration of reservoired hydrocarbons in the uplifted northern basins as tilted structures spilled up-dip or were breached during inversion erosion. As a result, many of the present-day accumulations are significantly smaller than peak burial accumulations. Simple mass-balance calculations indicate that more oil was generated in the basin than has so far been discovered. As much as 90% of oil generated in the basin was lost from the basin during uplift and tilting as breached structures were successively exposed. Such extensive loss of accumulated hydrocarbons is likely to be typical of inverted rift basins.