Full text loading...
-
Can we Correct for Azimuth Dependant Variations of Residual Move-Out in Land Waz Context, Using Depth Non-Linear Slope Tomography? An Imaging Case History
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 12th International Congress of the Brazilian Geophysical Society, Aug 2011, cp-264-00055
Abstract
High-density wide azimuth (WAZ) land surface acquisitions have demonstrated superior imaging capabilities. Apart from the traditional poor signal-to-noise ratio of land data we face a new challenge: the necessity of reconciling the kinematics of the various azimuths. In this paper, we present an imaging case history involving WAZ non-linear slope tomography. Using surface information (kinematic invariants), velocity model updates are performed both in depth and time. We chose to start from an initial pre-stack time migrated (PreSTM) dataset. After applying a structurally consistent filtering to improve the S/N ratio on stacked data, we used a dense automated tool for dip picking. In parallel residual move-out (RMO) was computed on all azimuths simultaneously. Our case study demonstrates that WAZ non-linear slope tomography in the depth domain greatly improves the imaging of the structures when compared to the initial PreSTM result. We observe that even if tomography in the time domain significantly enhances imaging, it cannot successfully honor the kinematics of the various azimuths within the constraints of time imaging assumptions. On the contrary, WAZ non-linear slope tomography in the depth domain offers an efficient way to reconcile these kinematics, thus promoting the use of depth imaging when processing high-density WAZ data, even in the context of mild geological complexity.