Interpretation of paleoenvironment using benthic foraminifera from Tertiary rocks, northern Sarawak

Department of Applied Sciences (Applied Geology), Curtin University Malaysia

Email: viviandayong@postgrad.curtin.edu.my

Abstract

In this work, we collected and examined three samples from an exposed 50 cm thick fossiliferous bed and prepared thin and polished sections for petrographic analysis. The benthic foraminifera assemblages and other marine fossils are studied to infer the paleo depositional environment. Based on the benthic foraminifera and their common ecological preferences, it is inferred that this layer has deposited between the intertidal and neritic zones, and within the photic zone, they are under oxygenated conditions. In addition, the presence of the glauconite mineral also supported the neritic environment interpretation, suggesting a water depth of less than 300 metres during the deposition, denoting shallow water conditions. Even though the results presented in this paper are at an elementary level, this could serve as additional information to develop a better understanding of the geology on a much larger scale.