Sequence Stratigraphy-Facies Analysis and Stylolite-Fracture Characterization Related to Porosity-Permeability in Carbonate Facies of Rajamandala Formation of Cikamuning Area, West Java-Indonesia
Riswanty, Maisi A.; Herlambang, Adhipa; Perdana, Lisnanda A.; Sapiie, Benyamin
Geology Engineering, Institut Teknologi Bandung, Bandung, Indonesia.
Rajamandala carbonate complex cropping out in Padalarang area, West Java, has been subject for detail studied by various researcher in conjunction with hydrocarbon exploration in Java Island. This formation is the only analog of Oligo-Miocene carbonate platform which represent major carbonate reservoir at East Java region. However, understanding facies architecture and their relationship to porosity distributions of this formation are poorly understood. The main purpose of this paper is presenting result of detail outcrop study in the Cikamuning area as part of Rajamandala Complex which has good exposure outcrops and can be used for representing model of Oligo-Miocene Carbonate model in Indonesia. The scopes of the study include numerous detail measuring sections, fractures scan-line location, modeling of carbonate facies, diagenesis, and fractures distributions. Furthermore, this study has primary objectives more specifically to identify and to model the relationship between carbonate facies, stylolite, and fractures characterization that can affect porosity and permeability. The analysis include 12 location of measuring sections, core descriptions of four wells, more than 100 thin sections samples and more than 1000 fractures measurements.
The sequence stratigraphy of Rajamandala Carbonate in Cikamuning shows two platform, turbidite sequence, and deep water carbonate that controlled by system tract and depositional system. The Cikamuning outcrops ENE-WSW trending are relatively complexly deformed with strike-slip fault cut the fold-thrust-system. The influence of carbonate facies to fractures system and stylolite is indicated by fracture density and intensity of facies. Result of quantity of stylolite (pressure solution) in measuring section is compared with facies and quantity of creatures and porosity. Stylolite will generate or enlarge porosity when it dissolved. Dissolved stylolite is stylolite that attained dissolution and generate secondary porosity. In conclusion, analysis of sequence stratigraphy, stylolite, creatures in facies, and fractures characterization can be modeled, and indicating the relationship that drive porosity and permeability.
AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012