BASEMENT CONFIGURATION AND DELINEATION OF NORTH EAST JAVA SUBBASIN BASED ON GRAVITY DATA ANALYSIS

• Main Author: Aprilia, Dearly
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/65514
• Institution: Institut Teknologi Bandung

The North East Java Basin is a very large sedimentary basin and has been proven to contain oil and natural gas. Gravity is a geophysical method that can be used to determine the subsurface configuration and to delineate sedimentary sub-basins based on density parameters. The purpose of this study was to determine the distribution of the gravity anomaly, estimate the depth of sediment, interpret the depth of basement and sediment in the North East Java Basin and surrounding areas. The research data used is secondary data and obtained from the Geological Survey Center (PSG). Data analysis used is spectrum analysis and filtering stage, namely butterwoth filter and bandpass filter. The result of this study is a map of the distribution of the Complete Bouguer Anomaly (CBA) with anomaly values obtained ranging from -39.8 to 63.1 mGal. Meanwhile, the results of the spectrum analysis show that the depth of the regional zone is around 16,671 km and the depth of the residual zone that is the place for sedimentary rocks is about 7,097 km. Judging from the results of the 2D forward modeling obtained for the results of the early stages of oil and gas exploration, namely estimating the existence of sub-basins and the depth of the basement sub-basins, the North East Java Basin area still has the potential as a place for the formation and maturation of oil and gas by showing that the basement is in the form of continental crust with a density value of 2.7 gr/cc. While the results of modeling on the bottom layer of basement are sedimentary rocks with Neogene age with a density value of 2.4 gr/cc.