Identification fluid content using AVO analysis and elastic impedance (EI) inversion on “v” field Cekungan Kutai, Kalimantan Timur

Abstract

A study case of identification fluid content using AVO (Amplitude Variation with Offset) analysis and Elastic Impedance (EI) inversion on “V” field located at Kutai Basin was done. Seismic partial angle stack was processed by using analysis of AVO and Elastic Impedance inversion produced output section such as Intercept (A), Gradient (B), Product (A.B), Scaled Poisson’s Ratio Changed, Near Angle Inverted, and Far Angle Inverted for further interpretation. AVO attribute analysis performed on the data field was included in class III AVO anomalies (low impedance contrast sand), and the Elastic Impedance inversion process was further performed by the three well (VB2, VA1ST, VA3) data processing and create log near EI and far EI as the inversion process controller. Well cross-plot between wells and inverted EI was also performed to determine the cross-section distribution on fluid in the reservoir. Result obtained in cross section inverted near angle zone that the gas is at the value of 9000 (ft/s)*(g/cc) up to 14200 (ft/s)*(g/cc), and the cross-section inverted far angle that the gas is at the value of 1100 (ft/s)*(g/cc) up to 1600 (ft/s)*(g/cc) at top reservoir in the period 2900-3300 ms. By slicing top reservoir map of AVO attribute and Inverted EI, reservoir distribution of reservoir sandstone have orientation direction from West to East until South-East.