The present study is an attempt to investigate the regional topography and drainage dynamics of the Khurar River, central India, along with the textural, mineralogical, and geochemical behaviour of the bedload sediments. The morphometric analysis was carried out using SRTM data with the help of ArcGIS 10 software. The area of the basin is 309.57 km 2 with its perimeter 83.24 km and maximum length 32.06 km. Drainage patterns are dendritic to subdendritic with stream orders ranging from first to third order. Drainage density is 0.34 per km 2 , while the bifurcation ratio is 4.5 for the river. The Khurar River Basin is an elongated basin of small size showing ENE-WSW trend analogous to the Son lineament. This basin might have originated during the Quaternary Period as a result of major tectonic activities in the region. The textural analysis indicates that the samples are bimodal to polymodal in nature ranging from very coarse to coarse grained and poorly to moderately well sorted in all the geomorphic units. The skewness value suggests coarse to fine-skewed values, while kurtosis value shows platykurtic to very leptokurtic nature of the sediments. The quartz, microcline, and albite are the chief minerals in the sediment samples with negligible variation from source to confluence of the river. The major oxide geochemistry of the sediments indicate that the dominant oxide is SiO 2 followed by Al 2 O 3 and other oxides that suggests felsic-dominated source for the sediments. The chemical index of alteration (CIA), plagioclase index of alteration (PIA), chemical index of weathering (CIW), weathering index of Parker (WIP), Vogt S. residual index (V), Ruxton ratio (R), and silica-titania index (STI) reveal moderate weathering conditions and immature nature of the sediments in the basin. These suggest that the sediments experienced a moderate amount of weathering in the river catchment under subhumid climatic conditions.

The Karmanasa basin is spread over the Kaimur sandstone (Upper Vindhyan) and marginal Ganga plain with the areal extension of about 7926 km 2. The quantitative approach of the basin development of the Karmanasa River basin was carried out by the morphometric parameters. The drainage network was extracted from SRTM data. The trellis pattern characterizes upstream of the drainage basin, while the dendritic pattern is noticed in middle and downstream of the basin. The drainage density (0.34-0.44) indicates that the basin has highly permeable subsoil and thick vegetative cover. Relatively larger values of form factor (SW-1, SW-2, SW-3, SW-6 and KW) signify higher flow peak for a shorter duration. High values of ruggedness number and relief ratio suggest that Karmanasa basin is prone to soil erosion. The present work shows that the Karmanasa basin is less prone to flood, vulnerable to soil erosion and a good resource of surface water. This study would help to utilize the water resources and extended for sustainable development of the Karmanasa River basin area.

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The present study helps to understand the relation between the different morphometric parameters to delineate the drainage characteristics of the Ghaghghar River Basin (GRB), Son Valley, India. Shuttle Radar Topographic Mission (SRTM) data were used to prepare the Digital Elevation Model (DEM), Aspect, Drainage, and Slope maps by using ArcGIS 10 software. The Ghaghghar River is third-order stream that exhibits dendritic to sub-dendritic pattern. The trails drainage patterns are also observed in some areas of the basin which may be due to the effect of regional tectonics. The mean bifurcation ratio is 5.1 showing normal basin which is somehow controlled by structural disturbances. High bifurcation ratio (>10) determines that the region is subjected to strong structural control on the drainage. Drainage density (0.36) shows very coarse drainage texture also having positive correlation with stream frequency. The elongation ratio is 0.64 along with circulatory ratio (0.6) shows elongated nature of the basin. The low values of drainage density and stream frequency imply that surface runoff is not quickly removed from the basin, making it susceptible to flooding and gully have very little effect on the extent to which the surface has been lowered by agents of denudation.

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The present study is an attempt to describe the geomorphic evolution of the Dongar River Basin, Son Valley, Central India. To achieve this target, a detailed field survey and morphometric analysis of the river have been carried out using Cartosat-DEM data with the help of ArcGIS 10 software. The basin area of the Dongar River is 35.17 km 2 having trellis and sub-dendritic to dendritic drainage patterns. The Dongar River is designated as fourth-order basin and lower order streams mostly dominate in the basin with the drainage density value of 1.21 km −1 . The stream order of the basin is predominantly controlled by physiographic and tectonic set-up of the study area. The slope of basin varies from 0°to 42.04°and is mainly controlled by the local geology and erosional cycles. The bifurcation ratio (Rb) for the studied basin varies from 1.58 to 4. The higher values of the bifurcation ratio, i.e., of second/third along with third/fourth order, reveal the regional geological and tectonic controls when river starts draining along the exposures of lower Vindhyan . The elongation ratio of the basin is 0.86 thus indicates high infiltration capacity, low runoff, and low-to-moderate slope of the river basin. The increase in stream length ratio from lower to higher order shows that the basin has reached mature geomorphic stage. The major trends of lineaments are ENE -WSW, i.e., almost analogous to Son-Narmada lineament suggesting that Son-Narmada lineament played an important role to control the drainage dynamics and evolution of the adjacent river basins. These features along the Dongar River and the orientation of the major lineaments suggest neotectonics, may be due to reactivation of the Son-Narmada lineament.

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Soft-sediment deformation (SSD) structures are the syn-sedimentary structures that can form by seismic as well as non-seismic processes. The SSD structures commonly occur in the Semri Group of the Vindhyan Supergroup in the Kajrahat Limestone, Chopan Porcellanite and Rohtas Limestone formations, and the Glauconitic Sandstone Member. The SSD structures include, slump folds, kink bands, chevron folds, convolute beddings, contorted cross-beds, flame structures, pinch-and-swell structures, breccias, sagging structures, water-escape structures, and dykes of varying dimensions. The lagoonal and tidal depositional environments of the Kajarahat Limestone Formation (not the continental slope environment) lead to suggest that the SSD structures formed as a result of the seismic activities in them. The SSD structures of the Chopan Porcellanite Formation associated with rhyolite might have originated as a result of volcanic activities or seismicity, while those occurring in the Glauconitic Sandstone Member (Kheinjua Formation) adjacent to the Son Lineament might have formed as a tectonics-related seismicity. The convolute bedding with large lateral extent in the Rohtas Limestone Formation looks related to seismicity in the light of its deposition along the shelf. Thus, the upper Palaeo-Mesoproterozoic Semri Group, Vindhyan Supergroup represents varieties of the SSD structures formed mostly by seismic processes. These imply that the Central India was unstable and was a place for tectonically controlled seismic events during the upper Palaeo-Mesoproterozoic (1,700-1,600 Ma).