Technology and Teamwork- The Key to Efficient Marine Seismic Acquisition in a Low Oil Price Environment

Abstract

The exploration business was especially hit hard when global oversupply and unmatched demand combined to send oil prices crashing down, causing oil and gas companies to cut back spending and halt projects. Meanwhile, the continued depletion of existing reserves demands new exploration for resource addition. In this paper we highlight how the collaboration amongst various stakeholders coupled with the use of innovative technology has enabled PETRONAS to acquire new 3D marine seismic surveys efficiently. High quality 3D seismic datasets were delivered within a very tight budget under diverse geologic settings allowing early realization of 3D sub-surface images. Marine seismic acquisition is extremely vulnerable to currents. Typical marine 3D survey accounts for double digit infill rates. A proactive approach using a combination of fan-mode acquisition, Fresnel zone based infill management and triple source blended acquisition, was successfully applied over the last three years in seismic operations to maximize survey efficiency and reduce cost and HSE exposure. Fan-mode is an acquisition technique where the streamer separation is increasing with offset. Since high frequencies are more attenuated at far offset and depth, the bin size can be varying along the streamer without compromise the overall data quality. In Fresnel zone based infill management, the premise is to analyze the coverage requirement based on the effects of increasing size of the coverage hole on the seismic data after it has been processed through Pre-Stack Time Migration. The objective is to only infill where it is deem geophysically required. Triple source blended acquisition increase sub-surface coverage of each vessel pass with highly attain nominal fold yet with the same amount of in-sea equipment. This, allow survey to be completed much quicker hence reduce the operational risk exposure. Successful implementation of these technological innovations requires a close understanding and collaboration amongst various stakeholders e.g. the client, the contractor, host authority, platform supervisors and the local community. This is to ensure that the operating procedures are well understood and implemented correctly and safely in field to achieve optimum results. Incorporating smart commercial models in the contracts and achieving synergy between multiple projects of similar scope has also paid dividends.

AAPG Datapages/Search and Discovery Article #90336 ©2018 AAPG Asia Pacific Region, The 4th AAPG/EAGE/MGS Myanmar Oil and Gas Conference, Myanmar: A Global Oil and Gas Hotspot: Unleashing the Petroleum Systems Potential, Yangon, Myanmar, November 13-15, 2018