Substructural Mapping Based on Potential Field Data in Part of Vindhyan Fringe Belt in Northern Madhya Pradesh, India

Abstract

Potential field methods are use to map the substructural features such as faults, fractures, shear zones and altered zones in the part of Vindhyan fringe belt of northern, MP. Geologically, the study area is represented by Vindhyan Supergroup of Meso to Neoproterozoic age. The area is mainly covered by alluvium which is characterized by river gravels, sand and residual soil. Bouguer gravity anomaly contour map brought out a broad gravity variation ‘high’ in southern part due to upliftment of basement rocks/ presence of denser rock below the Vindhyan formation, whereas gravity ‘low’ in northern part due to presence of low depression zone (altered/ weathered Sandstone and Limestone).The high dominant anomaly is observed in the southern and northern parts which may be due to effect of basement/ basic dyke of BGC and the presence of Ferruginous Shale and Ferruginous Sandstone, respectively. The ‘high’ residual gravity anomaly aligned approximately NW-SE is recorded and interpreted as inferred lineament on Bouguer gravity anomaly map in central part of the map which is reflected from shallow feature and not observed on geological map. The residual magnetic map shows clear increase of the numbers of the local magnetic anomalies with different polarities along with various shapes, extensions and orientations. The inferred as lineament in central part are clearly reflected in THDR and TDR map of gravity data, while the THDR of the magnetic data is not represented properly. The map of the TDR of the magnetic data depicts close to zero magnetic values that coincide with edges or boundaries of inferred lineament in central part of the map. The majority of solutions are falling varying depth from 0.5 to 2.5 Km. The solution of gravity data is falling at inferred lineament and contact between two litho-units varying depth from 0.5 to 2.5 Km in central part of the map.