Publications

The Barito Basin is located northwest of the Meratus Mountain in the heart of South Kalimantan. The basin foredeep is located at its eastern part. The foredeep has divided the basin into two parts: west of the foredeep is the Barito Platform with a weak deformation of thin-skinned tectonics, and east of the foredeep is a strongly deformed part with thick-skinned tectonics. Research conducted previously showed that thick-skinned tectonics in the Barito Basin developed from inversion tectonics. This paper demonstrates the evidence of inversion and the effects on the coal cleat characteristics of the Tanjung Formation, Barito Basin. The research was conducted in the Karangintan area, Banjar district with fieldwork as the main method. The Karangintan area is located east of the Barito foredeep. The lithology at this area is sandstone, shale, and thin coal for the Tanjung Formation, Pre-tertiary pyroxene andesite for the Pudak Formation, and Pre-tertiary chert for the Keramaian Formation. The geological structures at this area are NE-SW normal faults and NW-SE strike-slip faults. The evidence of inversion is the repetition of the Pre-tertiary Pudak Formation andesite and Eocene Tanjung formation outcrop distribution. The main inversion fault is the Balau Normal Fault, which separates the Karangintan area into two: a stable block, northwest to the normal fault, and an inverted block, southeast to the fault. Cleat measurements using the scanline method were conducted at the two blocks, with a measurement station at each block to compare cleat characteristics between the stable and the inverted blocks. The characteristics are cleat orientations, cleat intensities, and cleat apertures. The main difference is the cleat orientations, where the cleats at the inverted block have ENE-WSW orientations while the cleats at the stable block have NW-SE orientations. The difference is due to the different main stress orientations between the two blocks resulting from inversion development.