Creation of Geological 3D-Model of Komyshnianske Field Based on the Sequence Stratigraphy Principles

Abstract

Currently, the sequence-stratigraphic section dismemberment is only being implemented in Ukraine, so this article is highly relevant. The authors created geological 3D model of Komyshnianske gas condensate field based on sequence-stratigraphic section dismemberment for the first time at this area. This approach is effective for the following conditions:-insufficient field geological study;-thickness of productive horizons does not reach the seismic resolution boundaries;-no significant difference in impedance values on reflection horizons. The selected technique includes the following stages:-field geological study, facies analysis (integration of well geophysical complexes, cores);-deduction and correlation of sequence boundaries;-construction of discrete log, which corresponds to specific sequences distribution;-conducting seismic interpretation of the 3D seismic survey study of research area;-construction of a structural framework with the involvement of correlated sequences boundaries;-comparison of volume seismic attributes with selected sequences distribution. A geological 3D model of Komyshnianske gas condensate field was created based on sequence-stratigraphic principles. During the research, a geological structure of field was analyzed, the separated conditions of sedimentation (sequences) were deducted and interpreted. During the seismic interpretation of 3D seismic survey of study area, local features of wave field were identified, their reflection in the core material was found and linked to the concept of changing sedimentation conditions. With a general understanding of the material transportation and accommodation direction, used method allows to qualitatively outline the distribution boundaries of sedimentation certain conditions and predict their development outside the study area. Construction of facies discrete log and their distribution in the seismic field allows grouping thin bed layers of collectors to reach the seismic resolution and use them to predict the distribution of facies associated with changes in the rocks reservoir properties (tracking beach facies of deltas/avandeltas, sloping sediments, etc.). The constructed model could be used as a trend for reservoir distribution at the stage of construction of static geological model. Involvement of sequence-stratigraphy technique is new approach to sedimentation conditions study within Dnipro-Donetsk depression (DDD) areas. The paper shows that provided methodology gives:-improved geological understanding of field through sedimentation analysis and facies logging;-trends for reservoir properties distribution with the involvement of construction facies volumes;-proposals for further field E&D. The general provisions under conditions of geological materials sufficient base can be applied to other DDD areas, especially in pre-border zones. Involvement of sequence-stratigraphy technique is new approach for sedimentation conditions study within Dnipro-Donetsk depression (DDD) area. On the example of Komyshnianske gas condensate field, the article shows that provided methodology gives:-improved geological understanding of field through sedimentation analysis and facies logging;-trends for reservoir properties propagation with the involvement of seismic volume studies;-propositions for further field Exploration & Development.