Earth's crustal stress can be inferred from fluid flow of fractures in deep boreholes

To gain a deeper understanding of a wide range of geological processes, such as plate tectonics, earthquakes and volcanic diking, we need to have a knowledge of both past and present in situ stress field. In particular, information on crustal in situ stress at various spatial and temporal scales is crucial in dealing with issues such as oil and gas extraction, geothermal development, carbon dioxide and nuclear waste disposal—all of which are practical problems in the subsurface.