Himalayan Geology, Vol. 38 (2), 2017, pp. 184-192, Printed in India
Application of the Schmidt-hammer with relative-age dating of moraine boulders – a case study from Mandakini River valley, central Himalaya, India
TANUJ SHUKLA1,3*, MANISH MEHTA2, VIPIN KUMAR2, H.C. NAINWAL3, D.P. DOBHAL1
1Centre for Glaciology, Wadia Institute of Himalayan Geology, Dehradun 248001, India
2Wadia Institute of Himalayan Geology, Dehradun 248001, India
3H.N.B. Garhwal University, Srinagar, Garhwal 246174, India
*Email (Corresponding author): tanujshukla.geo001@gmail.com
Abstract: Recent developments in dating applications for paleoclimatic reconstruction have highlighted the inherent problems in dating of glacial environments. We have applied the Schmidt-hammer relative age dating approach on moraine boulders of Mandakini River valley, central Himalaya, India to establish the relative age dating constrain along with published absolute chronologies. The chronologically constrained landforms of the Mandakini River valley represent the four sets of glacial advancement and several set of glacial retreat phases. The Schmidt hammer rebound values (R-values) were collected from 13 locations at different altitude, with 40 impacts on each boulder per site and a total number of 520 values. The average rebound (R)-values for the Rambara Glacial Stage (RGS) are 37, Ghindurpani Glacial Stage (GhGS) are 47, Garuriya Glacial Stage (GGS) are 56 and Kedarnath Glacial Stage (KGS) are 63. We have suggested that the average rebound (R) values of glacial stages are found to be in linear relation with the published Optically Stimulated Luminescence (OSL) and Terrestrial Cosmogenic Nuclide (TCN) chronology. Considering the easy and economical nature of Schmidt- hammer rebound (SHR) technique, we are postulating that by generalizing the R-values for the rock types of glaciated terrains, this can be applied to high and remote altitude environments where the suitable datable materials are difficult to find. With an advent of that, we anticipate that such efforts can be another step for developing a acceptably accurate age calibration curves to reduce the requirement of absolute chronologies in glacial environment.
Keywords: Schmidt hammer, relative age dating, glacial chronology, central Himalaya.
