Oil and Gas Potential of the West Kamchatka Coast and Its Relation to the Structural and Tectonic Setting of the Sea of Okhotsk Region Based on Geophysical Data

This article describes the peculiarities of the deep-seated structure of sedimentary depressions in the West Kamchatka coastal zone and in adjacent Sea of Okhotsk offshore areas, which are manifested in the observed potential fields and in their transforms. To reveal geophysical regularities reflecting the old structure of the deepest part of the crystalline basement within the analyzed objects, a pseudo-gravity field calculated on the basis of analytical approximation was used. Regional and local components of the decomposition of the observed potential fields calculated by 2D adaptive energy filtering and presumably associated with different-depth structural-tectonic objects were analyzed. Based on comparison of the investigated Pustoretsky Trough with the “reference” Kolpakovsky Trough, which includes known gas-condensate fields (West Kamchatka Oil and Gas Region), conclusions were made about the similarity of their formation conditions and subsequent evolution. A regional geophysical model of the Pustoretsky Trough was compiled, which made it possible to reasonably assume its formation in the zone of Cenozoic subduction processes caused by the interaction of lithospheric plates. This model is thought to be associated with possible presence of oil and gas prospective structures.