Geologic signatures revealed directly from 3D seismic data from mexico using the coherence cube technique

Abstract

Application of the coherence cube technique has provided improved understanding of structural and stratigraphic details of the subsurface, leading to revised 3-D geologic models for the exploration and production of hydrocarbons throughout Mexico. Presented here is a brief description of the coherence cube technique, algorithms and various new applications with examples from both onshore and offshore Mexico. It is intended as both an introduction to the technology, and to demonstrate the power of its use as a complementary volume to the conventional seismic volume for 3-D seismic interpretation on the workstation. This technology reveals important geologic information that may be totally overlooked using conventional techniques. The ability to measure three-dimensional spatial variations in the seismic waveform, with full dip and azimuth comprehension and without any interpretation bias, is an extremely powerful capability. The basic seismic waveform contains a measure of time, frequency, amplitude and absorption quantities. These vary spatially as the recorded seismic responds to lateral variations in the physical and geometric properties of the subsurface geology. Measuring these combined changes in the seismic response allows the interpreter to map these changes if recorded by the seismic technique. However, the ability to recognize these changes is not always possible with conventional seismic data. The seismic coherence measurement, as applied here, is an attempt to capture these spatial changes. The use of the coherence method is well accepted by the geoscientists in Mexico as a tool to provide direct geologic signatures from 3D seismic data, thus improving the subsurface interpretation results of the 3D asset.