Karakteristik Mineralogi Tanah Tertimbun di Desa Sukasirna, Kecamatan Cibadak, Sukabumi
Abstract
Buried soil at Desa Sukasirna, Kecamatan Cibadak, Sukabumi was developed from different time of Salak Mountain eruption. The purpose of this research was to study the mineralogical characteristics of soil in different layers of these buried soil. The results showed that the soil exposure is composed from 4 buried soil. The soil and buried soil 1 contain magnetite, rock weathering results, clear quartz and plagioclase. Some minerals such as volcanic glass, weathered volcanic rock glass, hypersthene and turbid quartz were found in a little amount. Based on their mineral composition, soil and buried soil 1 have a basaltic parent material associated hypersthene. Minerals which dominantly found in the buried soil 2, 3, and 4 are magnetite, rock weathering results and weathered of volcanic rock glass. Some minerals such as plagioclase, hypersthene, hornblende, iron concretion, volcanic glass, turbid quartz and clear quartz were found in a little amount. Based on their mineral composition, buried soil 2, 3, and 4 have an andesitic parent material associated hornblende. DTA/TG analysis indicated that each layer in the soil and buried soil minerals contained kaolinite as a dominant clay mineral. Value ratio of Si, Al and Fe in all layers of the soil and buried soil were showed crystalline oxide form.