Compositional Variations and Analysis on Carbonate Turbidite and Debrite of Oligo-Miocene Rajamandala Limestone (Rajamandala Formation), Padalarang Area, West Java

Abstract

A detailed work on Carbonate Turbidite Apron Facies Association found that this FA is composed by several type of skeletal and non skeletal carbonate grain. The compositional variations appeared are related to their hydrodynamical process, carbonate clast provenance and sea level change while it deposited. On this research, turbidite and debrite compositions are determined and clustered into 16 types of skeletal and non skeletal grains as follows: Red algae, Pelloid, Micrite, Echinoderm, Coral, Miciritic envelope, Rhodolith, Molusc, Miliolide, Benthic Forams, Planktonic Forams, Ostracode, Bryozoa, Green algae, Lithoclast, and Intraclast. Analysis on type of shedding (refer to sea level change) have been done based on assumption that a highstand turbidites are poor sorted and mostly composed by large amount of shallow-water skeletal and non skeletal constituents such as green algae, red algae, shallow-water benthic forams (miliolids), and intraclasts. In the other hand, the lowstand turbidites are in better grain sorting and composed by a large amount of planktonic foraminifers and micrite. Analysis on type of shedding comes up with the result that the turbidite and debrite on this area are composed by both highstand and lowstand shedding deposit. Carbonate turbidite become an important issue according to some HC prospects in SE Asia. Detailed characterization on subsurface data for this kind of deposit, especially in relation to Stratigraphic Sequence analysis mostly are lack in rock data. Rajamandala Formation in Padalarang Area is the largest and the most diversed (in term of facies types) of Oligo-Miocene carbonate outcrope in Java that representing almost all architectural facies commonly appeared in subsurface Oligo-Miocene creservoir in West carbonate reservoir in East Java area including carbonate turbidite.

AAPG Datapages/Search and Discovery Article #90217 © 2015 International Conference & Exhibition, Melbourne, Australia, September 13-16, 2015