Spectral component geologic modeling: A novel approach for integrating seismic data into geologic models

摘要

For many geologic models, a more accurate realization of the reservoir may result from the integration of seismic data interpretations. For many years, however, it has been recognized that it is difficult to properly account for the unique scale and precision of these interpretations. Generally, this problem results in models that fail to precisely honor the input data and the target constraints, particularly the vari-ogram model. Spectral component geologic modeling honors all input data. The compositional (phase) and continuity (amplitude) information contained within the interpreted spectral components is preserved in the constrained geologic model. Continuity as defined by the variogram model is also honored, but generally only for those frequencies that are not represented by the spectral components (e.g., the higher frequencies). The target lithofacies proportions are exactly honored in the final lithofacies model. One could argue that the seismic-data interpretations and the variogram model represent "soft" information; i.e., that our confidence in these data is limited, and therefore we should not exactly honor these inputs. However, what is our alternative? Should the model honor something other than our interpretations? Whether these inputs represent our single best interpretation of the reservoir or they represent one of multiple possible interpretations, the resulting geologic model should always precisely represent the input data, as it does with SCGM.