General geology and depositional environment of the semanggol formation in Bukit Kepah, Kuala Nerang

The study area is located at Bukit Kepah, Kuala Nerang in Kedah district. Kuala Nerang located at northern part of Kedah and 34 kilometers away from Alor Setar town. Bukit Kepah is located near to Kuala Nerang town and connected by only one main road. The land of this area is mostly covered by paddy field and settlement. The purpose of this study is to update geological map of the area and to determine the depositional environment of the Semanggol Formation. Based on the literature reviews, Kuala Nerang composed of the Kubang Pasu Formation and Semanggol Formation but after doing ground geological mapping, it can be interpret that Bukit Kepah area is exposed to Semanggol Formation only. Depositional environment of the Semanggol Formation was determined by using lithostratigraphy analysis by observing and interpreting the lithology, sedimentary structures, and fossils. The depositional environment could be tidal flat environment based on fine grain of sediment rock and crinoidal stem fragments found. The fine grain sediments indicate the deposition occurred at low energy current and low relief area. The fragments of crinoidal stems found is proof that the flowing medium for deposition is water and the fossil is believed are transported to tidal flat area during high tidal level. Hence, it could be in subtidal to intertidal zones.