Geodynamics of the Ural Foredeep and Geomechanical Modeling of the Origin of Hydrocarbon Accumulations
The paper presents the tectonic and geological characteristics of the Ural-Novaya Zemlya Forebelt of Hydrocarbon Accumulations and reports results derived from studying the origin of hydrocarbon accumulations in upthrust structures in the forebelt's eastern flank. The eastern flank was affected by intense thrusting and folding of western vergence in relation to continent-continent collision during the closure of the Ural paleo-ocean in the latest Paleozoic and, in the northernmost segments of the belt, in the mid-Mesozoic (Cimmerian folding phase). The eastern flank of the Southern Ural segment of the belt is deformed by arrays of large-amplitude folds and upthrust faults. For this segment, geomechanical and petroleum systems modeling was performed, and the research results were used to construct a conceptual model of the origin of hydrocarbon accumulations in zones of fold-upthrust structural parageneses (in upthrust structures) and subthrust zones (in structural elements beneath thrusts). It is demonstrated that upthrust-fault and subthrust structures in the Ural Frontal Fold Zone were favorable to the accumulation of oil and gas pools.