A Strong Earthquake on February 5, 2022 (ML 5.5) near a Petroleum Deposit on the Northeastern Shelf of Sakhalin Island.

An upper crustal earthquake (ML 5.5) occurred on February 5, 2022 at 21:18 GMT (08:18 local time on February 6) at the northeastern shelf of Sakhalin Island. The earthquake is related to a displacement along the Piltun–Chaivo Fault, which was ignored from consideration as a seismogenerating source until recently. This earthquake occurred in an area of positive increments of critical stresses caused by the catastrophic 1995 Nefterorsk earthquake. The nature of the studied earthquake is most likely tectonic. The accumulated tectonic stress together with static stresses, which were initiated by the strongest earthquake at the northeast of the island, led to vertical displacements (a reverse fault) along an east-dipping fault. The earthquake source is characterized by latitudinal almost horizontal compression stress. The first instrumental data on strong ground movements in the nearest earthquake zone have been analyzed, which is valuable for engineering seismology. The macroseismic data according to the internet response from the local population are analyzed. The results of this work can be relevant from the practical viewpoint, because economic human activity on the exploration of mineral deposits expands each year. Thus, the current data on active geological structures in the shelf zone promote the refinement of a seismic potential of oil and gas producing territories. [ABSTRACT FROM AUTHOR]