Carbonate Facies Model and Paleogeography of Tendehhantu Formation, Northern Kutai Basin, Indonesia
Amiarsa, Dadan P.; Kurniawan, Idham A.; Susanto, Artedi; Tabri, Kristian N.
Geology, Institut Teknologi Bandung, Bandung, Indonesia.
The Kutai Basin is one of the famous hydrocarbon production and deepest sedimentary basin basin in Indonesia. Located in the Easternmost of Sundaland and formed since early Tertiary as rift basin to aborted rift after Miocene age. The present day dominant structural trend is a series of tightly folded, NNE ± SSW trending anticlines and synclines forming the Samarinda Anticlinorium which is dominant in the eastern part of the basin. Different from the center of Kutai Basin, The Nortern Kutai basin has carbonate complex which is developed in Miocene age.
The research area is located in Tendehhantu carbonate complex which has represented by 2 research locations i. e: Sekerat and Kaliorang area. The methods of this research are using field observation and laboratory analysis. The field mapping has been conducted by 3 researcher in 3 different locations to observe the rocks outcrop in the field locations. This each locations represent each facies that are back reef, reef crest and fore reef. The laboratory analysis has been done are petrography, calcimetry, and microfossil analysis to identify the ornament of each facies mocroscopically.
The "Atol" Tendehhantu has completed various carbonate facies. At the back reef (western part) consist of mudstone facies, intercalation of wacke-packstone facies which has abundant of foraminifera fossils and rudstone facies which has abundant fragmental of corral fossil. At the reef crest (middle part) of Tendehhantu dominantly consist of boundstone organic buildup facies which characterized by growth of head corral fossil. At the fore reef (eastern part) consist wackstone facies and packstone facies which is abundant of plantonic foraminifera.
Based on this study, paleogeography of Tendehhantu Formation at Miocene age is mostlikely carbonate Atol which has about 30 Km in diameter in geometry. The paleo position of back reef is relative to westsouthern and the fore reef is located relatively northeastern.
AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012