Comparison of OBN and Legacy NAZ Seismic Surveys at Ewing Bank, GOM

Jonathan P. Parker, Claudia Montoya, Michael Murat, Richard Uden, and Oleg Yakovlev
[email protected]

Historically, conventional narrow-azimuth (NAZ) seismic acquisition in the Ewing Bank area has limited azimuth sub-surface illumination and production platforms have created a shortage of near offset data in key data areas. In 2011 an ocean bottom node (OBN) seismic survey was acquired to mitigate the effects from these issues on the sub-surface evaluation and deliver a broader seismic signal bandwidth with higher signal-to-noise ratio to improve the input dataset used for reservoir characterization and prospect evaluation. Due to the unique nature of OBN acquisition the survey provided both up-going and down-going wavefield datasets. The up-going wavefield is a more traditional dataset which uses the primary reflections while the down-going wavefield is created by using the first order water leg multiple. For comparisons with the NAZ data we concentrated on using the down-going wavefield OBN data, but important distinctions observed between the up-going and down-going wavefield OBN data are also reported.

AAPG Search and Discovery Article #90167©2013 GCAGS and GCSSEPM 63^rd Annual Convention, New Orleans, Louisiana, October 6-8, 2013