Application of 3D seismic visualization techniques for seismic stratigraphy, seismic geomorphology and depositional systems analysis: examples from fluvial to deep-marine depositional environments

Abstract

In recent years, 3D seismic has become an essential tool for the interpretation of subsurface stratigraphy and depositional systems. Seismic stratigraphy in conjunction with seismic geomorphology, calibrated by borehole data, has elevated the degree to which seismic data can facilitate geological interpretation. 3D seismic data has enabled interpreters to visualize details of complex depositional systems, which can be incorporated into borehole planning for exploration as well as development needs to improve risk management significantly. Common techniques for geological visualization include (1) imaging stratigraphic horizons, (2) time slicing and flattened time slicing, (3) interval attribute analysis, (4) voxbody interpretation and mapping, (5) 3D perspective rendering and (6) opacity rendering.One of the key benefits of modern 3D seismic interpretation is that stratigraphic horizons can be interpreted and horizon attributes (such as reflection amplitude, dip magnitude, dip azimuth, and curvature) can then be imaged directly in 2D or 3D space. Techniques such as variable illumination can enhance geomorphological interpretations, and, when integrated with stratigraphic analyses, can yield insights regarding distribution of source, seal, and reservoir facies. Stratigraphic intervals bracketing sections of geological interest can be evaluated for amplitude and frequency content and can contribute to geological interpretations. Time slices and flattened time slices (also referred to as horizon slices) can bring to light map patterns and geological features that other techniques might overlook. Voxel picking can further bring out features of geological interest. This method involves auto-picking of connected voxels of similar seismic character, a technique that can illuminate discrete depositional elements in three dimensions. Similarly, opacity rendering, which makes opaque only those voxels that lie within a certain range of seismic values, can further bring out features of stratigraphic interest. Examples of fluvial, shallow marine, and deep marine depositional environments are shown. A variety of visualization techniques are applied to these examples in an effort to illustrate the variety of interpretation techniques available to the geoscientist. These examples will highlight the integration of seismic stratigraphic and seismic geomorphological analyses essential for maximum benefit to be derived from geological analyses of 3D seismic data.