New Prespective Paleogeography of East Java Basin; Implicationrespond to Oil and Gas Eksploration at Kujung Formation Carbonate Reservoar

41st HAGI Annual Convention and Exhibition 2016

Aprilana, C.^1 ; Premonowati, P.^1 ; Hanif, I.S.^1 ; Choirotunnisa, C.^1 ; Shirly, A.^2 ; Utama, M.K.^2 ; Sinulingga, Y.R.^2 ; Syafitra, F.^2

Universitas Pembangunan Nasional VETERAN Yogyakarta, Indonesia^1

SKK Migas, Indonesia^2

关键词: Depositional environment;    Geophysical data;    Hydrocarbon generation;    Middle Miocene;    Paleogeography;    Reservoir quality;    Rock characteristics;    Trapping mechanisms;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/132/1/012006/pdf
DOI  :  10.1088/1755-1315/132/1/012006

来源: IOP

【 摘 要 】

Paleogeography is one of critical points that always less considered by explorationist in the world. Almost all of the consideration is focused on trapping mechanism. Paleogeography is guidance in understanding both of physical and chemical of rock characteristic which will correlate with its depositional environment. Integration of various geological and geophysical data such as; tectonic, structural geology, stratigraphy, lithology, and biostratigraphy will lead us to a better understanding of rock characteristics. Six paleogeographic interpretations was made consist of; Early Tertiary (P5-56-55 ma), Middle Eocene (P14-41 ma), Late Oiligocene (P22-25.5 ma), Early Miocene (N7-16.5 ma), Middle Miocene (N9-14.5 ma), and Pleistocene (NN19-1.5 ma). That six paleogeographic interpretations are assumed represent the paleogeographic evolution of East Java Basin time after time. In Middle Eocene time, it would be more than hundred possibilities regarding the location where the formation deposited. This would be controlled by the existence of some local structural paleohighs and horsts which oriented NW-SE followed by their own sedimentary transportation path. With assumption that hydrocarbon generation was occurred in 15 Ma and the depth of maturation window lies on about 2,500 m depth. Therefore, the possibility of source rock maturation is high, due to almost of the clastics sediment of Ngimbang deposited into the series of grabens. The Kujung reef types simplified defines and categorize into; 1) Patch Reef 2) Berrier Reef 3) Pinnacle Reef Over Isolated Reef. Kujung Carbonates were deposited in Early Miocene when regional transgression occurred. The depositional environments were dominated by shallow marine littoral-sublittoral. Generally, the reservoir quality of this Kujung Carbonate shows fair to good quality, in range7-32% porosity, and 1-1400 mD permeability (internal SKK Migas data).