Challenges in Seismic Data Acquisition and Processing-The Petronas Experience

摘要

PETRONAS has been actively acquiring large volumes ofrnseismic data in varied and difficult terrain to support itsrnworldwide exploration, development and production activities.rnIn the Malay Basin of Malaysia, the challenge begins withrnimaging complex stratigraphic reservoirs that are often belowrnconventional seismic resolution. The Malay Basin being arnfairly matured exploration & production province alsornposes another challenge, i.e. acquiring high quality seismicrndata around platforms and other obstructions.rnIn Vietnam, our team was tasked with imaging complexrnfractured basement reservoirs under an overburden of clasticrnand volcanic rocks while in Indonesia, obtaining high quality,rncontiguous data over a land-marine interface required fourrndifferent acquisition techniques and special processingrnworkflows. In offshore Mozambique, East Africa where strongrncurrents prevail in a N-S direction, binning and stackingrnmethodology was used to ensure a thorough reflection of thernsubsurface. The high elevation changes in the mountainousrnregion of Yemen called for a special array design, dualrnelevation and hybrid static routines, while under the dunes ofrnAlgeria, the low relief structures needed proper accounting ofrnstatic variation through modeling.rnThis paper outlines the various technical challenges faced inrnthe above regions and the solutions that were designed forrnthem. While specific solutions are required in specialrncircumstances, PETRONAS underlying objective is to acquirernoptimal data that will last the life cycle of a field where thernsurveys form the base cases for eventual reservoir monitoringrnthrough 4D seismics. Imaging through gas clouds, detection ofrnfractures and improving resolution of thin pay sands and sealsrnare some of our continuing challenges. With strong focus onrnproactive resolution of technical issues, the operationalrnchallenge of striking the right balance between quality, costrnand efficiency is managed. Health and safety and preservationrnof the environment during seismic operations remain as anrnunderlying principle of PETRONAS.