Estimation of Basement Depth and Structural Boundary using 3D Euler Deconvolution, Tilt Angle Derivative and Tdx Derivatives using Ground Gravity Data of Thrust-Fold Belt Area of Mizoram State.

摘要

The hydrocarbon exploration in the north-eastern part of Himalayan belt is always a challenging task due to complex geological features and thrusted/faulted geology. Seismic methods are always used for hydrocarbon exploration, however in such kind of hilly terrain, logistically difficult and geologically complex areas; seismic imaging cannot provide fruitful desired solutions to estimate the basement depth for better hydrocarbon exploration. To overcome these problems, joint interpretation of gravity-magnetic data can be very useful. In this paper, an attempt has been made to study the complex basement depth estimation and source-edge detection using 3D Euler deconvolution (ED) technique, Tilt angle derivative (Tdr) and Tdx derivative (Tdx) using Bouguer gravity anomaly data of the study area falling in the Mizoram state. Different types of derivatives of the gravity data have been studied to enhance the anomalous features and identifying the better structural lineament. The Euler deconvolution technique has been applied for basement depth estimation with the help of structural indices and window sizes. It is concluded that deeper basement depth more than 10 km estimated in some areas. The dominated patterns of the structural trends are oriented in north-south direction. The results derived using these three methods have similar to each other for distinguishing the location of structural lineament. The results carried by Euler deconvolution, Tilt derivative and Tdx derivative are superimposed by the identified faults carried through the geological field work illustrated a very good correlation. This study also signified additional fault locations in this study area. The results derived using these methods are helpful for better understanding the structural boundaries and basement depth for hydrocarbon exploration.