2D Geological Structure Modeling of the Jabungan Area Based on Magnetics Method
Keywords:
Jabungan field, magnetics, gradien analysis, normal fault, 2D modelingAbstract
Magnetic secondary data processing from 30
measurement data had been carried out in
Jabungan. This study gets a structural model of
Jabungan subsurface using gradient analysis and
2D modeling. Initial processing performed on daily
variation correction and IGFR (International
Geomagnetic Reference Field) to get anomaly
contour of total magnetic field. The next process is
upward continuation to obtain local anomaly
contour and regional anomaly with conducting
reduction process to the poles to get magnetic
anomaly pattern which is singular pole. We
analyzed the local anomaly with gradient analysis
and 2D modeling. The result of this gradient
analysis showed fault structure in the northwestsoutheast Jabungan and matched with a geological
map of the research area. Profile sampling was
carried out from contour result second vertical
gradient such as cross section against the
estimated fault area and process it into a graphic
to decide the fault types. The graphic analysis
result showed that the existence of normal fault.
The 2D modeling result revealed the rocks types in
Jabungan comprise sandstones, gravels, marls,
tuffs, and clay stones.
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https://doi.org/10.23883/ijrter.2018.4300.zf6
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