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Flat pebbles and edge‐wise fabric in the Mesoproterozoic Rohtas Limestone Formation (RLF) and the Chikkshelikere Limestone Member (CLM), India, generate a new insight into their formation. Simple stacks of alternating dark micritic and light‐coloured microsparite planar layers in the targeted sedimentary successions manifest a low‐energy depositional background, disturbed only occasionally by weak storms. While the dark layers are homogeneous, light‐coloured layers are generally planar, wavy ripple laminated, and bear frequent load casts. The dark layers often display varieties of 2‐D microbial mat structures little known from carbonate formations. In compliance with their identity, they are comparatively enriched in carbon, a large part of which is organic and kerogen. The said structures with their intrinsic deformations indicate delayed cementation. Notwithstanding delayed cementation, the flat clasts in these formations are readily traceable to the dark laminae possibly because of early acquisition of their selective cohesiveness. Resultant stress led to brittle deformation in the mat layers, while the light‐coloured layers underwent ductile deformation. All the studied breccias bodies are in situ, but this fact does not preclude either the possibility of reworking of the clasts while exposed to high‐energy current or generation of intraclasts by high‐energy currents eroding the depositional surface. [ABSTRACT FROM AUTHOR]

Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the Thomas River, near Maihar, central India. Part of these deformation structures have most probably a non-seismic origin, but other structures are interpreted as resulting from earthquake-induced shocks. These seismic structures are concentrated in a 60 cm thick interval, which is interpreted as three stacked seismi-tes. These three seismites are traceable over the entire length of the section. They divide the sedimentary succession in a lower part (including the seismites) deposited in a hypersaline lagoon, and an upper open-marine (shelf) part. Most of the soft-sediment deformations outside the seismite interval occur in a lagoonal intraclastic and muddy facies association. The SSDS within the seismite interval show a lateral continuity. They record simultaneous fluidisation and liquefaction. The bases of each of the three composing seismite bands are defined by small-scale shear folds, probably recording an earthquake and aftershocks. The presence of the three seismite bands at the boundary between the lagoonal and the overlying open-marine oolitic facies association suggests that the seismic event also triggered basin subsidence. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses a distinctive event bedset encased by coastal erg-margin deposits, at a preferred stratigraphic level near the base of the Neoproterozoic Upper Bhander Sandstone in central India. The bedset is composed of couplets of sandstone beds that exhibit incisive amalgamation although they differ in geometry, structures (at soles, within and at tops of beds), vertical grain-size variation as well as palaeocurrent pattern and direction. The wide extent of the bedset is evident from several exposures spread over a distance of more than 50km roughly in strike-parallel direction. Flow and depositional dynamics interpreted from the coupled event beds are more consistent with a tsunami origin than alternative palaeogeography-compatible models of climate-induced storm, flash flood or accentuated tide deposits. A palaeotsunamiite model is thus discussed, with separate incoming and outgoing components. Considering the overall depositional setting to be an epeiric sea coast in an intracratonic sag basin, the relevant bedset is inferred to reflect the record of a teletsunamiite; it would also be one of the very few Precambrian tsunamiites known so far. Exceptional preservation of this possible tsunamiite was facilitated by sheltered deposition behind the backshore zone and the berm, as well as by rapid burial by wind-deflated sands and advancing aeolian dunes. [Copyright &y& Elsevier]

Abstract: Three-dimensional facies variability in coarse clastic sedimentary rocks (breccia, conglomerates and coarse-grained sandstones) at the base of the Ramdurg Formation suggests terrestrial scree and fans giving way downslope to fluvial sediments along the margin of the Mesoproterozoic Bagalkot basin in India. In consistency with the basic tenet of Precambrian alluvial sedimentation, fluvial architectural elements and field location-specific consistency in channel-flow direction support an invariably braided pattern for the rivers, although the architectural element-packaging pattern does show distinct changes downslope, with channel belts thinning and becoming more regular in their geometry. With possible persistence of a semi-arid climate, downslope change in flow durability in the channels was controlled primarily by water discharge, depending on position of the channels with respect to the mean level of the water table–basin-margin slope intersection. Confined between an unconformity below and a granular lag succeeded by thoroughly wave-featured sandstone, and argillite-carbonate above, the coarse and poorly sorted clastic sedimentary rocks of the basal Ramdurg are interpreted as a base-level lowstand product, for which the sedimentation rate exceeded the rate of space creation for sediment accumulation. Consequently, the fan succession as a whole is coarsening-upward. Fluvial sections, nonetheless, fine upward as the depositional slope gradient became progressively reduced with aggradation of channels. Tectonics-related slope variation along and across the basin-margin, devoid of vegetation, dictated the sediment distribution and sequence building pattern primarily. Eventual termination of this basin-margin depositional system was caused by later enhancement in the rate of base-profile rise. [Copyright &y& Elsevier]

Examines the bedding-plane markings for implications of early evolution of animals in Vindhyan, India. Query on the biological origin of the markings; Estimation on the inclusive dates of the deposit of sediments; Suggestion on the evolution of complex metazoans.

Three dominant sociological approaches in analyzing agrarian social structure in India are: the approach which regards "tradition" as an intrinsic element of and conceptual referent in the study of structure; the approach using "natural", "native", or "indigenous" categories as providing basic analytical tools in the study of social structure. As the view that positions in the secular order are indistinguishable from positions in the sacred or ritual order came to be gradually challenged by sociologists, the need for an independent class analysis began to be felt. Questions regarding "points of domination" of capitalist social relations in agrarian structure, as exemplified by the mode of production debate in India influenced class analyses. The debate attempted to isolate the "points of domination," in the agrarian structure where the development of commodity relations occurred under colonialism. At the village level, sociologists using the framework of mode of production attempted analysis of agrarian social structure in terms of classes. Two different approaches in class analysis can be distinguished in these attempts: distributional and structural.

Abstract: Stratigraphic architecture of the fluvial interval at the base of the Neoproterozoic Sonia Sandstone, Rajasthan, India has been evaluated in consideration of the vegetationless Precambrian depositional environment. For its critical appreciation, facies, architectural elements, bounding surfaces, deductive palaeohydraulics, palaeocurrents, distribution of soft sediment deformation structures, as well as sequence stratigraphic status of the interval have been taken into account. Confined between an unconformity at the base and an overlying transgressive lag, the interval is considered a lowstand product. Temporal shifts in base profile, nevertheless, affected the tripartite division of the LST, systems tract developed during relative sea level lowstand. Palaeocurrent diversions across division boundaries as well as preferred concentration of soft sediment deformation structures along the top of the middle division make the role of tectonics evident. Facies, architectural elements, palaeohydraulic derivations as well as the degree of palaeocurrent consistency depict significant differences in channel patterns between the divisions. The axiom regarding braided patterns, frequent avulsion, and the ephemeral nature and flashy behavior of Precambrian rivers find conformity only in Division II. The river systems in Divisions I and III had frequently become meandering, due to valley constriction in the former and bank stability in the latter. Division I accumulated through sediment aggradation within a constricted valley incised deeply into the bedrock during the preceding course of base profile fall. Channel amalgamation characterizes Division I and more profoundly, Division II. The sharp upward transition from Division II to III records rapid enhancement in the rate of rise of base profile due to basin subsidence leading to encroachment of the contemporary sea. Mud settling was encouraged because of ponding at the downstream end turning the river channels fixed. Eventually the depositional site was drowned under the sea. [Copyright &y& Elsevier]

The intracratonic rift-related Mesoproterozoic Rampur Shale in Kudri, India formed in the marine mid- and outer shelf domain. It bears a dominant imprint of shore-parallel, storm-driven flow, as predicted by oceanographers for modern shelves, and thus differs from other ancient storm deposits in the geological record. In the Rampur Shale, gutters are shore-parallel, while tool marks of various kinds are both shore-parallel and shore-normal, and show bipolarity in both directions. Hydrodynamic analysis and inter-relationships between the flow features suggest that the storm-driven flow was shore-parallel, dominantly unidirectional and steady initially, and that it became increasingly unsteady thereafter, while also becoming dominantly shore-normal during peak oscillation. As storm conditions waned, the gutters were filled by sediments under dominant wave influence. These Rampur data are consistent with observations made in modern seas and suggest that storm-driven flows, in general, have evolved in the same way over time, although their geological records may vary in details because of local constraints. [Copyright &y& Elsevier]