PRELIMINARY RESULT OF MARINE GEOLOGICAL SURVEY FOR SUPPORTING BELITONG GLOBAL GEOPARK F.X. HARKINS H. PRABOWO (a*), NUR ADI KRISTANTO (a), FAUZI BUDI PRASETIO (a), IMELDA ROSIANA SILALAHI (a), SITI MARINA (a), YULI YULIANAH (a), CATUR PURWANTO (a), YUSUF ADAM PRIYOHANDONO (a), SONNY MAWARDI (a), GODWIN LATUPUTTY (a), PRISCA AYU WASTUWIDYARANI (a), ADI C. SINAGA (a), LULI GUSTIANTINI (a)
a) Marine Geological Institute, Geological Agency - Ministry of Energy and Mineral Resources, Jl. Dr. Junjunan no. 236 Bandung, 40174.
Abstract
One of the 10 UGGp in Indonesia is the UGGp Belitong, recognized as a global geopark since 2021. Geosites of Belitong Geopark are mostly found on the beaches including the 241 small islands surrounding Belitung, hence marine geology and oceanographic information are essential to protect the existence of the sites. Therefore, this study was conducted in order to get information on marine geology and oceanography surrounding Manggar Waters, east of Belitong, that is useful in marine areas planning and information enrichment of geological heritage. We conducted a bathymetrical survey by using an echotrac echosounder, current measurement by infinity, sediment characteristic analyzed from 40 seabed surface sediment samples, and coastal characteristic mapping. We investigated the morphology of small islands including Bukulimau and Siadung by UAV drone. The result indicates that the sediment characteristic is dominated by coarse sediment particularly sand, and clayey sand. Gravel is also found nearby Buku Limau island. Microfauna foraminifera contained in the marine sediments is rather low divers, dominated by Operculina and Amphistegina. The beach morphology of Manggar is characterized by 2 types are rocky beaches in the northern part composed of igneous rock Units, and flat beaches in the southern part, composed of beach alluvium deposits units. Abrasion is dominant in the southern part, particularly in the southern of Tambak Beach. The beach of Both Buku Limau and Siadung Islands are characterized by flat beaches, composed of coral reefs. The coastline of both islands is characterized by sandy coast and rocky coast.
