Petrology and Geochemistry of Ciremai Volcano, West Java, Indonesia: Evidence of Open-System Magma Dynamics

Keisha Prillia Qayyima (Department of Geological Engineering, Bandung Institute of Technology, Bandung)
I Gusti Bagus Eddy Sucipta (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Asep Saepuloh (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Nurcahyo Indro Basuki (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Very Susanto (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Niniek Rina Herdianita (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Mirzam Abdurrachman (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Idham Andri Kurniawan (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Prihadi Soemintadiredja (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)
Emmy Suparka (Petrology, Volcanology, and Geochemistry Research Group, Department of Geological Engineering, Bandung Institute of Technology, Bandung)

IJOG : Indonesian Journal on Geoscience
Vol. 13 No. 3 (2026)

Ciremai Volcano is the youngest active volcanic system within the Ciremai Volcanic Complex (CVC), located on the northern coast of West Java. This study aims to further investigate the characteristics of the magmatic system as part of the Sunda Arc. The activity of the CVC is divided into four periods: Putri Volcano, Gegerhalang Volcano, Wurung Crater, and Ciremai Volcano with its parasitic cones. The magmatic evolution of the CVC is reflected in the characteristics of its lava throughout its volcanic history. Petrographic analysis reveals that the volcanic rocks of the CVC are predominantly composed of plagioclase, pyroxene, olivine, hornblende, and opaque minerals as phenocrysts. The magma exhibits calc-alkaline affinity, with Fe enrichment during the early stages of magma formation. The enrichment of incompatible elements (Sr, K, Rb, Ba, and Th), depletion of HFSE (Nb, P, and Ti), and the presence of xenoliths suggest a convergent margin setting, with a continental-derived sediment enrichment in the magmatic source. Both petrological and geochemical analyses indicate that the magmatic evolution of the CVC has an interconnected open-system magma dynamic. Major basaltic injections and mixing of basaltic magma likely triggered a significant eruption at the end of Gegerhalang and contributed to the development of new magma conduits. Besides fractional crystallization, the post-caldera magmatism of Wurung Crater, Ciremai, and its parasitic cones is affected by a prolonged basaltic influx and magma reheating.