South Sumatra Basin

The South Sumatra Basin is most southern back arc basin of Sumatra Island. It is bounded to the west by an active volcanic arc along the Sumatra Fault System.The basin has long petroleum history. Significant number of oil and gas fields were discovered in this basin. Example of several seismic section across several fields in this basin are displayed here:
1) Suban Field
2) Kaji Semoga

Depth to basement map of South Sumatra Basin shows the isochrone contours in Two-Way-Time. The map shows the position of oil and gas fields relative to the depocenter (Darman & Yuliong, 2020)
1. Suban Field

The Suban Field is located on top of a basement high as shown the following regional section prepared by Hennings et al, 2012 (in Marino Baroek, 2015). The stratigraphic units described in this section are:
6. Upper Nuicebe-Pliocene sandstone, shale, coal, volcanic - Kasai Formation
5. Middle-Upper Miocene sandstone and shale
4. Lower-Middle Miocene organic shale and rare sandstone - Telisa Formation
3. Lower Miocene platform and reefal (3a) carbonate - Batu Raja Formation
2. Paleogene/Neogene granite wash and clastic sequences - Lemat and Talangakar Formations
1. Sub-Cenozoic crystalline and metamorphic basement

Hennings et al, 2012 also prepared a field scale seismic section, showing several segments of the field, named Southwest, Centre and Northeast Domain, shown on the following figure.

2. Kaji Semoga Field

Hutapea et al., (2000) published some information about Kaji-Semoga field in South Sumatra Basin.

Two seismic sections of Kaji and Semoga Field are displayed here:

Section A went from West to East, crossing both Kaji and Semoga Field.
The lowest horizon in red is the top of the granitic basement. Both Kaji and Semoga Field are consist of carbonate reefs of Baturaja Formation, which built on top of basement high.

Section B is a North-South section across Kaji Field. Generally the basement is getting deeper southward in this part of the basin.

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