General geology of Kampung Pulai, Gua Muasang Kelantan and Source-Depositional Environment of Crude Oil from Field 1.

The geological study was conducted to determine the all the features and process that occur at the study area related to geology. Geological mapping of study area and thin section analysis were conducted. Geographical Information System (GIS) used to analyzed data collected. Study area was located at Kampung Pulai, Gua Musang, Kelantan. Gua Musang underlies at the Centre Belt of peninsular Malaysia. Study area located at Gua Musang formation and consist of two stratigraphic and historical which is Paleozoic and Mesozoic. Structural geology of the present day also used to determine information about the history of deformation. The geomorphology of the study area consists of mountains, hills and plain area (alluvium). Galas River as the main river and consist of parallel, radial and dendritic drainage pattern. Two type of rock can be found in this area which is sedimentary rock limestone a.nd metamorphic rock slate. Joints structure can be found mostly at the isolated tower-like hills of the limestone. For specification, biomarker analysis used in determining the depositional environment of crude oil sample. Open column chromatography method used for preparation of the crude oil before conducted in the Gas Chromatography-Mass Spectrometry (GC-MS). GC-MS conducted using m/Z 85 for n-alkane, m/Z 191 for hopane and m/z 217 for sterane. For n- alkanes, CPI index, Pr/Ph ratio and degree wamess parameter gives teirigenous environment, costal environment with suboxic conditions and also suboxic conditions for the three parameter respectively. In Hopane Ts(Ts/Tm), (Ts/Tm), C₃₁/C₃₀, and C₂₉/C₃₀ ratio parameter was used and result shows oxic condition, higher shale contain, non- marine depositional and also clay rich (shale) depositional environment respectively. For sterane, ternary diagram and C₃₀/C₂₇-C₃₀ gives marine depositional environment. C₂₁/C₂₉ ratio parameter indicate the depositional environment from higher plant organic matter.