Geological structure and depositional environment of sediments in the North Erawan field, Pattni basin, Gulf of Thailand

Abstract

The Erawan Field is located in the central Pattani Basin, Gulf of Thailand. The objective of this study is to explain the geological structure and depositional environment of the sediments in the northern part of Erawan Field by using 3D seismic, well logs including mud log data. Structure is interpreted from 3D seismic data resulting faults and horizons interpretation. The main structure is N-S trending graben system with minor synthetic/antithetic fault in NNE-SSW direction. The structural closure is relating to west-dipping fault. Based on the well logs and mud log interpretation, the study area was developed in fluvial depositional environment with different vertically dense sand. The section studied can be divided into 4 units. Unit A is possibly avulsed-channel belts deposit. Unit B could be overbank deposit. Unit C could be complex meandering belts deposit. Unit D is possibly meandering belts deposit.