Uncovering Stratigraphic Plays With Point Source Point Receiver Acquisition in Environmentally Sensitive Areas

Abstract

The development of high channel count acquisition systems in combination with high productivity acquisition techniques and stakeless positioning has led to significant improvements in onshore seismic acquisition efficiency. This efficiency has resulted in reducing the cost of acquiring full azimuth surveys with long offsets in all directions with fine source and receiver point sampling. Dense symmetrically sampled point-source point-receiver data are required to preserve amplitude and phase of the recorded wavefield and to ensure adequate noise removal. Full azimuth data and associated amplitude preserving processing has resulted in ability to study not only isotropic amplitude variation with offset (AVO) effects but also anisotropic AVO. This is requires sufficient traces with a proper distribution in each azimuth gather for reliable AVO estimate in each azimuth sector. The requirement for determining azimuthal anisotropy effects sufficient traces at larger take-off angles are even stricter as a sufficient number of traces needed above a certain take-off angle. Due to environmental and cultural heritage constraints orthogonal geometries with relatively wide line intervals are preferred in the deserts of Australia. Using these line spacings with dense source and receiver points along the lines combined with high energy output vibroesis source allow to shoot high resolution seismic with extremely low enviromental impact. However these designs tend to suffer from a lack of traces in the near- and medium-offset ranges and typically have highly irregular fold distribution in different offset/azimuth sectors affecting the quality of the final image and extracted seismic attributes. Recent studies showed that single sensor data can be used in combination with interpolation and regularisation techniques to increase the density of the original acquisition grid and remove irregularities introduced during seismic acquisition addressing the underlying limitations of the imaging and inversion engines that imply uniform sampling. This paper describes how recent advances in seismic acquisition and data processing can be used for mapping Permian gas plays in the Cooper Basin as well as the relatively shallow conventional oil bearing Hutton and Poolowana formations.

AAPG Datapages/Search and Discovery Article #90217 © 2015 International Conference & Exhibition, Melbourne, Australia, September 13-16, 2015