International Journal of Educational Research and Reviews

ISSN 2329-9843

International Journal of Education Research and Reviews ISSN 2329-9843 Vol. 7 (4), pp. 001-006, April, 2019. © International Scholars Journals

Review

Upper mantle velocity structure in the NW Himalaya: Hindu Kush to Garhwal region from travel time studies of deep Hindu Kush earthquakes

Sushil Kumar1*, R. Chander2 and K. N. Khattri3

1Scientist (Seismologist), Wadia Institute of Himalayan Geology, P.B.No.74, Dehra Dun –248 001(UA), India.

2I.I.T. Roorkee, Roorkee, formerly University of Roorkee), 290, Sector 4, Mansadevi complex, Panchkula – 134109, Haryana, India.

3I.I.T. Roorkee, Roorkee, formerly University of Roorkee), 100 Rajender Nagar, Dehra Dun-248001 (UA) India.

Accepted 09 January, 2019

Abstract

The 22 Hindu Kush earthquakes had focal depths in the range of 50 to 245 km approximately. The 154 P travel time readings obtained from them were interpreted using a computer program based on least squared inversion and written specifically for the purpose. The upper mantle P- wave velocity along the north-west Himalaya obtained from this study has a value of 8.1 km/s. It appear to persist up to a depth of about 100 km below that level, it appears to increase to 8.35 km/s. The upper mantle P- wave velocity is found to be comparable to that obtained along a DSS profile in Kashmir. However, it is lower by 0.35 km/s from the value estimated by Ni and Barazangi in 1982.

Key words: NW Himalaya, P travel time, upper mantle structure, Hindu Kush to Garhwal Himalaya.