Danni Gathot Harbowo, Aswan, Siti Khodijah Chaerun, Widi Astuti, Yahdi Zaim
– Residents of Jasinga, West Java, consistently reported the presence of an abundance of wood fossils. We examined geological settings and wood fossils to investigate the paleovegetation types in the region. This research aims to map the distribution of wood fossils and interpret the paleoenvironment based on paleontological evidence. Lithostratigraphic measurements were performed, followed by a description of wood fossil anatomy in micro-thin section observations, isolation of palynological fossils from the host rock through chemical preparation techniques, and geochemical analysis using X-ray fluorescence spectroscopy. Our findings indicate that the area comprises Pliocene fluvial-volcanoclastic deposits containing several dipterocarp wood fossils, including Parashoreoxylon, Dryobalaonoxylon, Shoreoxylon, Anisopteroxylon, and Dipterocarpoxylon. There were also non-dipterocarp wood fossils from Apocynaceae, Combretaceae, Fabaceae, and Olacaceae. Most wood fossils in these deposits were silicified (SiO2: 92.7 ± 1.88%), preserving the wood tissue structures. Additionally, the wood fossil-rich strata contains fossilized palynomorphs, including pollen fossils from Dipterocarpaceae, Convolvulaceae, and Florschuetzia, and spore fossils from Stenochlaenidites, Verrucatosporites, and Lygodium, indicating the presence of a more diverse paleovegetation. These results support the existence of paleotropical rainforests. Our study suggests that paleoclimatic and paleovolcanic settings have significantly shaped the paleotropical rainforest ecosystems in the southern part of Sundaland during the Early Pliocene. © 2024 by Chulalongkorn University
Geological Engineering Study Program, Faculty of Earth Science and Technology, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung, 40132, Indonesia; Department of Metallurgical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung, 40132, Indonesia; Department of Geology, Institut Teknologi Sumatera, Jl. Terusan Ryacudu, Wayhui, Lampung, 35365, Indonesia; Research Center for Mining Technology, National Research and Innovation Agency (BRIN), Jl. Ir. Sutami Km. 15, Tanjung Bintang, Lampung, 35361, Indonesia