PEMETAAN SEBARAN LITOLOGI DAN POROSITAS RESERVOIR HIDROKARBON MEMANFAATKAN METODE INVERSI ACOUSTIC IMPEDANCE (AI) DAN MULTI-ATRIBUT DATA SEISMIK FAR-OFFSET

Abstract

Seismic method is usually used for imaging of underground level as image geology level and reservoir rock characteristic. Seismic attribute is often used in exploration analysis with seismic data. Actually, there is no seismic attribute which explain all lithology of a layer. So, it is needed to get good combination between seismic attribute data and other hydrocarbon data such as geology data. One of seismic attribute which can be used to image hydrocarbon reservoir lithology is acoustic impedance. Inversion which is performed to acoustic impedance will get cross section result of acoustic impedance spreading which explain the reservoir lithology. Multi-attribute method can be used to predict and model of rock porosity from seismic attribute. Apply of this method is used to map the acoustic impedance and porosity (neutron porosity) from multi-attribute method. Result of mapping which is obtained from both, then performed overlay. Results of the research are acoustic impedance inversion and multi-attribute seismic method which apply to far-offset seismic data produce map of reservoir lihology and rock porosity spreading. The value of acoustic impedance where explain a reservoir is between 32500 (ft/s)*(g/cm3) to 42500 (ft/s)*(g/cm3) and neutron porosity value is between 0,05 to 0,2 in fraction scale.