Himalayan Geology Vol.22 (2), 2001, pp.61-82, Printed in India
Seismic mapping of photogeomorphic anomalies observed in the area between Hamirpur and Sundernagar, Himachal Pradesh, Himalayan Foothills with an emphasis on Hydrocarbon Prospectivity
A.K. DAS., P. BHAUMIK, S.S. BISHT & BHUMIJA AGARWAL Basin Studies Division, KDMIPE, ONGC, Dehra Dun – 248 195, India
A number of geomorphic anomalies of varying shapes and sizes were identified in Kangra-Lambagraon area. H.P. by Remote Sensing Lab. Of KDMIPE on the basis of drainage, tonal, and textural pattern from satellite images. All these anomalies lie within the inner tectonic belt between Jawalamukhi Thrust to the west and Main Boundary Thrust to the east. Four such anomalous features fall within Hamirpur-Sundernagar area, marked as ‘A’,’B’ and ‘C’.
The paper makes an integrated approach with an aim to investigate the extension and behaviour of these anomalies in the subsurface. With the help of seismics, well data and surface geological informations, time structure maps on four seismo-stratigraphic levels (Tops of Pre-Tertiary, Subathu, Lower Dharamsala and Upper Dharamsala Formation) have been prepared. All the anomalies are represented either by a ‘high’ or a ‘high’ trend in almost all the levels mapped although there is considerable shift in their positions. The Hamirpur structural ‘high, close to geomorphic anomaly ‘A’ is also manifested in the gravity and magnetic anomaly maps. The structural trend in the area, as deciphered from the gravity magnetic data and time structural mapping, swings from NW-SE to N-S, then to NE-SW as one moves from west to east. The Changartalai structural feature, encased in the subsurface in the triangle zone between Barsar Back-thrust and Kallar Thrust, has probable exploration play in Paleogene section which could not be fully assessed in the well ‘X’.
Source rock geochemical data acquired for Early and Pre-Tertiary sediments are inadequate to derive reasonable conclusion about the hydrocarbon generation potential of these sediments in the area.
