Environmental Geology of Semujur Island, Bangka Belitung Archipelago Province

Abstract

Semujur Island is an inhabit small island with an area around 145,000 m2. The island position is on the east side of Bangka Island with high marine potential. The study conducted using a geological survey for getting information on land, groundwater, seawater, and marine sediments. The analysis types are petrologic of soil or sediments, the geochemical analysis of dark well water, seawater, and marine sediments. The results of the study, Semujur Island is formed by sand dun of loose bioclastic material of carbonate pieces with grain-sized sand and gravel resulting from the marine organisms decomposition like reefs, mollusk, and foraminifera shells. The unconfined shallow groundwater system flows in bioclastic to be able to fulfill all populations. The composition of Pb is <0.0250 mg/l in all dark well water under the threshold. Abrasion and seawater intrusion also occur on Semujur Island.