| Popis: |
Summary A seismic survey has up to five dimensions: the 3D cubes with inline, crossline and 2-way time (TWT) dimensions as well as offset and azimuth. With repeated measurements (4D seismic), there is an additional axis: the elapsed time. Time-lapse seismic data can then be seen as a six-dimensional volume or a 5D movie. In traditional pre-stack studies, amplitude is analyzed as a function of incidence angle (AVA) and/or azimuthal direction (AVAz). In this paper, we propose a tool to extend the analysis of the Amplitude Versus Offset (AVO) behavior in conjunction with the elapsed time dimension. The changes in AVO with elapsed time provides a data reduction, that can lead to a clean 4D response of the changes observed through the monitoring period. Its applications to various processing and interpretation processes are discussed in the paper. |
