#TITLE_ALTERNATIVE#

• Main Author: ARIESTY KUSUMASARI , BRENDA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/13337
• Institution: Institut Teknologi Bandung

The geological mapping has been done based on the surface rocks dissemination in order to understand the geological arrangement of Waymuli and surrounding area. The research was followed by particular study about geochemistry of geothermal fluids to gain more knowledge about the characteristic of geothermal fluid in Mount Rajabasa, South Lampug Regency, Lampung Province. The geological mapping area is geographically located on 5°49’00,00”-5°50’20,45” South Latitude and 105°36’30,00”-105°39’30,00” East Longitude which includes Waymuli Village in Kalianda Subdistrict up to Kunjir Village in Rajabasa Subdistrict, South Lampung Regency. The geological mapping has been done in area of 15 km2 with a 1:10.000 scale. In order to gain more understanding about geochemical of its geothermal system, five water samples and one gas sample were taken from Mount Rajabasa. Geomorphology of mapping area can be divided into two units, namely Medium Volcanic Foot Slope Unit and Low Volcanic Foot Slope Unit. River flow pattern of the mapping area is radial pattern with young geomorphic stage. Stratigraphy of the mapping area consists of four unofficial litological units. These litological units, from old to young, are Cugung Pyroclastic Flow Unit, Waymuli Pyroxene Andesite Unit, Gunung Botak Andesite Unit, and Beach Alluvial Unit. Geological structure found in the mapping area is a relatively northwest-southeast normal dextral fault. Mount Rajabasa in South Lampung has geothermal potential which can be included into geothermal system associated with Quartenary volcanism and magma intrusion. The geothermal system of Mount Rajabasa is estimated to consist of three reservoirs, namely Sumur Kumbang reservoir in the northern foot slope of Mount Rajabasa, Gunung Botak reservoir, and Kunjir reservoir in the southern foot slope of Mount Rajabasa. Based on the geothermometer calculation, the temperature of these three reservoirs is about 260°C.