Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

Amalava Bhattacharyya ¹, Santosh K. Shah ², Vandana Chaudhary ³

Affiliations
1 Birbal Sahni Institute of Palaeobotany, 53-University Road, Lucknow - 226007, IN
2 Birbal Sahni Institute of Palaeobotany, 53-University Road Lucknow - 226007, IN
3 Department of Science and Technology, New Mehrauli Road, New Delhi - 110 016, IN

Abstract

Tree-rings are good proxy records for dating Paleoseismic events. In a reconnaissance tree-ring analyses in the Northeast Himalayan region we find that several conifers of this region are suitable for the various aspect of dendroecological analysis. In this paper we have discussed the feasibility of tree-ring width data of Abies densa growing at two distantly located sites of North-East Himalaya, Yumthang in Sikkim and T-Gompa in Arunachal Pradesh, towards dating Paleoseismic events. We have recorded that growths (ring-widths) are low either during the same year of known high intensity earthquakes of this region or subsequent year when it occurred during non-growing season of the tree. This implies that dated tree-ring sequences could be a promising tool in dating Paleoseismic events of the Northeast Himalaya. Since lower tree growth also noted in several non earthquake years, so for precision in application of tree ring in paleoseismic dating several tree-ring features other than ring width need to be considered along with proper selection of sites and trees preferably trees confine along the fault zones.

Keywords

Earthquakes, Tree-Rings, Growth Suppression, Reaction Wood, Paleoseismic Events, NE India.

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