Mirzam Abdurrachman
Ciremai Volcano is an active volcano in West Java, Indonesia. Based on geological observation, this volcano has erupted as central and flank eruptions. One of flank eruption products can be observed on Sukageri area. The products consist of ‘a’ā lava and pyroclastic fall deposits. This research is focus on ‘a’ā lava characteristics using petrology methods including textural analysis and crystal size distributions. Petrography analysis shows that the ‘a’ā lava consist of vesicular (16,04-47,85%), phenocryst of plagioclase (10,6 -12.4%), pyroxene (1,66-2.78%), olivine (0.87-3,25%), and opaque mineral (0,3-0,42%). Groundmass (65,29-83,53%) of the ‘a’ā lava consists of microcrystalline of plagioclase, pyroxene, and glass. Crystal size distribution (CSD) analysis shows 2 trends and concave curve which indicate a progressive change in ΔT during magma ascent. The existence of microcrystalline indicates that before magma was erupted, it stayed on conduit for ±41 days. After the eruption, the ‘a’ā lava needs ±13 days for cooling and solidifying.
Penerapan Teknologi Tepat Guna, Penerapan Karya Tulis
Ciremai Volcano is an active volcano in West Java