Multisource stress data constraints on Cretaceous—present regional tectonic stress field evolution in the southern Jinzhou area, North China Craton

Abstract

Abstract Regional tectonic stress fields are key crustal stress elements that drive tectonic movements and are associated with regional tectonics and geological resources. Regional tectonic stress field evolution of the Jinzhou area, located in the eastern block of the North China Craton (NCC), may provide a deeper understanding of tectonics of western Liaoning and the NCC. This work conducted borehole television, hydraulic fracturing and focal mechanism solutions to invert the paleo and present regional tectonic stress fields. Four groups of tensile fracture in the southern Jinzhou area were identified via borehole television, and their azimuths were NNW–SSE, NWW–SEE, nearly W–E and NE–SW in temporal order representing four stages of extensional tectonic events. Hydraulic fracturing and focal mechanism solutions showed that the stress status was normal fault and strike-slip, revealing that the southern Jinzhou area is undergoing NEE–SWW-oriented compression and nearly N–S-oriented extension in accordance with the strike-slip mechanism. From the Early Cretaceous to the present, the direction of the regional extensional stress in the southern Jinzhou area has evolved counterclockwise and sequentially from NNW–SSE to NWW–SEE, W–E, NE–SW and nearly N–S, and the regional tectonic mechanism has transited from extension to extension-strike-slip to strike-slip, leading to the current tectonic framework.