Tectonics Activity and Volcanism Influence to the Garut and Leles Basins Configuration and the Implication on Environmental Geology

Iyan Haryanto, Emi Sukiyah, N. Nurul Ilmi, Y. A. Sendjaja, E. Sunardi

Abstract: Garut and Leles basins are located in the Quaternary Volcanic mountain chain which was formed by the modern subduction. Both basins are similar to the Bandung Basin, with a different geological setting background. The Bandung Basin entirely bounded by fault structures, whilst the Garut and Leles basin are bordered by a combination of faults and Quaternary volcanoes. In this study, the morphological observation through DEM data set used to determine the fault occurrence and the relative age distribution of volcanic rocks derived from each of the volcanic cone body. Then, these data are used to analyze the historical geological process of both basins which has a connection with their geometry and position. These basins are classified as a tectonic basin which is controlled by two major northeast-southwest strike-slip faults. So then, the riedel shear system is applied to the center area in between these two faults which then produces the pull apart basin. Moreover, the second basin geometry show as a relatively ellipse geometry with the long axis trending of northeast-southwest

Keywords: Garut Basin, Leles Basin, extensional basin, compressional tectonic regime, riedel shear