GEOLOGI DAERAH CIMINCUL DAN SEKITARNYA, KECAMATAN KASOMALANG, KABUPATEN SUBANG, PROVINSI JAWA BARAT

This research aims to analyze geomorphology, stratigraphy, and geological structure in Pasanggrahan Village and its surroundings, Kasomalang Sub-district, Subang Regency, West Java. This is to determine the main control of the abundant spring water in the study area. The research methods used include literature study, study and making pre-mapping maps, field data collection, and data analysis and processing. The results showed that the research area consists of two geomorphological units, namely the Steep Volcanic Hills Unit and the Slightly Inclined Volcanic Wavy Plain Unit. The stratigraphic arrangement of the study area consists of four rock units, namely Lahar Breccia Inserted in Tuff Sand, Tuff Sand, Crystal Tuff, and Andesite Lava. The geological structure of the study area consists of primary structures in the form of twin and vesicular braces, and secondary structures indicated by horizontal faults based on the analysis of alignment patterns and spring manifestations. The geological history of the study area is influenced by the subduction of the Indo-Australian plate under the Eurasian plate, which caused volcanic activity and the formation of volcanic arcs. Rock formations in the study area were formed from volcanic activity during the Tertiary to Holocene-Recent periods, with contributions from volcanoes such as G. Tangkubanparahu and G. Tampomas.