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Himalayan Geology, Vol. 30 (1),
2009, pp.85-94 Printed in India
Quaternary Evolution of the Ganga River System: New Quartz Ages and
a review of Luminescence Chronology
PRADEEP SRIVASTAVA1*, UMA KANT SHUKLA2
1Wadia Institute of Himalayan Geology, Dehradun - 248001, India
2Department of Geology, Banaras Hindu University, Varanasi - 221005, India
Abstract : The Ganga foreland basin is amongst the largest such
basins in the world and has recently been studied by several groups.
Considerable confusion on the chronology has been created on account of
poorly informed interpretations. We review the existing chronological
framework and add new luminescence chronometric data from the Ramnagar
section along the Ganga River at Varanasi. This section is dated using the
Single Aliquot Regeneration (SAR) on quartz. The age data indicated that the
(1) sedimentation of this 20 m thick section started prior to 59 ka and
continued at least up to 7 ka (2) ages from five samples are in
stratigraphic order and confirm the ages given by Srivastava et al. (2003a)
from the same section that were derived using Multiple Aliquot Additive Dose
(MAAD) protocol on fine-grained feldspars and quartz (3) Quartz palaeodoses
derived are as high as 186±11 Gy that can yield to OSL ages of ~60 ka and
this is in contrast to earlier suggestion of an upper bound of ~35 ka. |
