Publications

Converted seismic wave data is not often used in exploration, due to the large cost of multi-component acquisition and the limitations of this approach. Multi-component seismic recording captures P to P seismic images (PP) as well as the converted wave, P to S seismic images (PS). The latest seismic acquisition over Bekapai Field, Mahakam PSC, has acquired both P-P and P-S seismic data. Given PP and PS stacked seismic data well registered in the interval target of H-2 to H-6, this paper will show comparison result between single independent Zp-Zs seismic inversion with joint PP-PS seismic inversion in three overlapping time windowed areas within the target zone. . The result of Vp-to-Vs ratio section from both the single independent Zp-Zs seismic inversion and the joint PP-PS seismic inversion was studied in order to achieve more detailed enhancement as the ratio would react sensitively to the smallest amount of value change in PP impedance section or PS impedance section. Based on this comparison, it is shown that Vp-to-Vs ratio section of joint PP-PS seismic inversion achieves much better resolution (higher frequency range) compared to the section for single independent Zp-Zs seismic inversion. The estimated property (Vp-to-Vs ratio) also the structure image in the area far from the well position. This improvement, mainly in the delineation aspect, is a contribution of the PS converted seismic that is known to better visualize the geological structure in the seismic section. The resolution of the single independent Zp-Zs seismic inversion shows noticeably lower frequency range. The strongly deviated well near the weak fault zone shown in the 2D Seismic Section affected the inversion result as well as the thin layers of the target. Given the PS and PP seismic stacks show a good registration for the target area, the converted wave seismic data could give more benefit in improving better image resolution and layer delineation in Bekapai Field.