New field observations on the Quaternary geology and vertebrate palaeontological occurrences in the Narsinghpur region of Narmada valley (central India)

Abstract

Abstract Since the beginning of the nineteenth century, the Narmada River Valley has been well known for discoveries of abundant vertebrate fossil localities, a wide range of prehistoric archaeological assemblages and the first-known hominin fossil site in India at Hathnora. The fossil and archaeological remains are found in various sedimentary contexts: boulder conglomerate, pebble-rich sand, cross-bedded, coarse-to-fine sand and reddish brown clay in the Early to Late Pleistocene deposits. Our preliminary field investigations in the Narsinghpur region of the basin mark the presence of 26 individual localities within a stretch of 70 km of the Narmada River and adjoining tributaries. Each location was documented by GPS and the geological details were recorded while collecting the fossils. Past and current palaeontological research has revealed that a variety of fauna adapted to the sub-humid climate of both aquatic and terrestrial landscapes that thrived in this area during the Pleistocene period. One of our long-term goals is to understand the reasons for the high number of palaeontological occurrences compared with other parts of India and use such information to predict the locations of new occurrences, including hominin fossils. Various taphonomic processes in this region are responsible for the preservation and destruction of fossil assemblages in different geological formations: soil type, climatic conditions, rich calcium carbonate presence, encrustation, patination and modern anthropogenic activities (among others). Most of the fossil localities are found at an elevation range of 310–350 m above mean sea level (AMSL). The Narmada Basin was inhabited by prehistoric human populations and a variety of fauna, as evidenced by the ample lithic and fossil assemblages across the region. There are definitive contextual patterns of occurrences of the Quaternary vertebrate fossils and archaeological assemblages in the landscape, which require detailed investigations and mapping to understand the spatial distribution pattern and nature of associated sedimentary environments. In addition, this uniquely fossil-rich area requires proper protection and long-term preservation as it is heavily impacted by modern anthropogenic factors such as agriculture, sand mining and other activities.