INDO-BURMESE COLLISION OCCURRED AT EOCENE EVIDENCE FROM THE DETRITAL
FISSION TRACK THERMOCHRONOLOGY OF NORTHEAST INDIA
Abstract
Nagaland is part of the northern extension of the Indo Myanmar
range(IMR).This area is representative of several orogenic upheavals in
the Cretaceous-Tertiary that form a relativelyyoung and mobile land
belt.Nagaland is the most recent crustal reaction to the collision of
theIndian and Burmese Plate.Barail formation emerged at the active
margin of the Indo-Burmeseplateconvergence.The majority of the available
tectonic replica proposes that themalformation and uplift of the
Northeastern. We aimed at the highlights of exhumation andsedimentation,
and its other host processes like provenance characteristics of the
Barail sandstones from Nagaland, India.Systematic geological mapping of
approximately 50 square meters has been carried out in the study area.A
geological map of the study area was made on a scale of 1:50,000 in the
Indian Topsheet No.58M/4 survey in the Kohima district of Nagaland.The
region was mapped according to need and accessibility by taking the
traverses along the highways, footpaths and across the ranges.In this
study,four quarry samples disseminated in various folds in the Barail
Group yielded the ages ranging from 37.4±1.5Ma to 49.9±2.4Ma and younger
than their predecessor sedimentary deposition ages(86.92-181.81Ma).The
binomial distribution clearly stated that from 46.0to32.0Ma,the grain
ages fitted peaks are usually dominated by the youngpeak.Combined with
an interpretation of the origin,the detrital zircon of the young peak
age and rocks indicated that most significant uplifting of the Barail
Group occurred during EocenetotheOligocene,almost timed to coincide with
the colliding of the Indo-Burmese plate more around
~35-50Ma.Such findings have been consistent with the
current geology of Naga Hills in theprovince of Nagaland.