Carbonate Reservoir Top Boundary Layer Identification Based On a Thickness-restricted Matching Pursuit Algorithm
Event name: 79th EAGE Conference and Exhibition 2017
Session: Carbonate and Evaporite Environments, Stratigraphy and More
Publication date: 12 June 2017
Info: Extended abstract, PDF ( 1.24Mb )
Price: € 20
Two peculiar geological phenomena were discovered in the interface of an Ordovician carbonate reservoir and clastic rock strata in the central Tarim Basin: 1) limestone has been developed locally in the period of shale deposition presenting paracontinuity with the underlying limestone deposition; 2) a karst carbonate reservoir had developed on the unconformity surface of the top limestone layers, and the reservoir impedance was similar to that of the overlying shale layers. That's why "diachronism" may occur in the seismic record, which covers the actual reservoir and strata information. For this reason, a thickness-restricted residual signal matching pursuit algorithm was proposed to explore much more accurate seismic information for the characterization of geological bodies. First, the original seismic data were decomposed into many atoms with different frequencies as a constraint to the thickness of the geological body. Then, the decomposed low-frequency atoms with their resolution ratio lower than the geological body were rejected, while the top-class atoms characterizing the geological body were screened from the remaining atoms to reconstruct the seismic signal. Finally, the re-obtained seismic data were applied to predict the reservoirs and the distribution of limestone strata.