EVOLUTION OF SUNDA COMPLEX MAGMA CHAMBER AND ITS RELATION TO MOUNT MANGLAYANG

• Main Author: Purnama Agung, Alkautsar
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/40636
• Institution: Institut Teknologi Bandung

Research area is located near Sunda Complex and Mount Manglayang, West Java, in coordinates 6,70º S - 6,91º S, dan 107,55º E - 107,78º E. Sunda Complex is a volcanic complex that includes an active volcano, Mount Tangkuban Perahu, and located in boundary of West Bandung Regency, Purwakarta Regency, and Subang Regency, while Mount Manglayang is a dormant volcano located in NE of Bandung City, in Cilengkrang District, Bandung Regency. Sunda Complex is inferred has a huge magma chamber. However, its relation with Mount Manglayang is still unknown. Moreover, an explosive eruption in the past was responsible of a caldera forming and Lembang Fault forming that lies west - east in this research area. This Mount Manglayang that stand in near the easternmost point of this fault pointing a hypothesis that there is a connection between Manglayang and Sunda Complex. Therefore, igneous petrogenesis analysis is needed to knowing the processes underneath the volcanoes, by doing petrographic analysis with thin section and a XRF test on geochemistry analysis. The samples taken from five (5) locations representing Sunda Complex and another five (5) lava flows in Cilengkrang River that representing Manglayang, particularly Young Manglayang Mount. From petrographic analysis, three of five locations in each mountain expressing similar magma chamber condition cycle, while the geochemistry analysis shows that those three locations of each mountain also expressing the same point, either the major elements (indicating magma source) or the trace elements (indicating magma enrichment). Thus, Sunda Complex and Mount Manglayang share the same magma chamber, with Manglayang acts as a parasitic volcano of Sunda Complex.