This article presents some results of the sequence-stratigraphic analysis performed at the Minkhovskoye field in connection with the discovery of gas deposits in the Lower Cretaceous clinoform complex (Akhskaya formation).
The Minkhovskoye gas condensate field is located in Western Siberia on the northern shore of the Taz Bay within the Tazovsky District of the Yamalo-Nenets Autonomous District of the Tyumen region. In conformity with the accepted oil and gas geological zoning, it is located in the Messovsky oil and gas bearing area of the Gydan oil and gas region. The reduction in size and complexity of new objects in the Neocome of Western Siberia, together with the increase in the resolution of modern 3D seismic exploration, require further development of the clinoform concept. It follows from a number of modern works based on the modern model-independent methodology of sequence stratigraphy. The use of genetic sequencing for this purpose, firstly, makes it possible to fully utilize the vast experience gained during clinoform modeling, and secondly, it better corresponds to the practice of dividing the section into regional reservoirs and cap rocks. As a result of drilling N well in the Akhskaya formation of the Neocom of the Minkhovskoye field, two gas-saturated objects were identified, displayed on time sections in the form of two echelon-like intense negative anomalies. During the sequence-stratigraphic analysis, it was found that both objects are part of the Pym 2 genetic sequence. The lower one is the body of coastal-marine sandstones as part of the HST system tract, and the upper one is the body of coastal-marine sandstones as part of the lower parasequence of the FSST system tract. Judging by the forms of dynamic anomalies, the sand bodies in both cases were formed as a result of the progradation of the lobed (delta) type coast. The fact of the proven gas bearing capacity of these stratigraphic elements poses the task of their further mapping outside the Minkhovskoye seismic cube. The small area of the seismic cube has not yet made it possible to clarify the gas potential of submarine fan and shelf sand bodies in the upper parasequences of the FSST, as well as the gas potential of the shelf formation as part of the LST. This requires more extensive field studies.
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