Abstract: To ensure the safety of supercritical carbon dioxide storage in sandstone lens bodies，the initiation，propagation and evolution of cracks were studiedA lenticular geological model and a numerical calculation model were established to analyze the transport mechanism of supercritical carbon dioxide fluid in fracturesABAQUS numerical simulation software was used to establish a fluidsolid coupling model for fracture propagation simulationThe results show that when there are initial cracks，the cracks appear to be long，fast，and curved，and when there are no initial cracks，the cracks appear to be short，slow，and flatIn the case of 0° and 30° initial fracture angle，the change of fracture width and area with pore water pressure is similar，showing a linear increasing trend as a whole；in the case of 60° initial fracture angle，the change of fracture expansion is complex，which mainly depends on the selection of initial injection point and migration channel in injection fractureThe results of the study should be paid attention to in the selection of carbon dioxide storage sites