Fluid injection interruption causes temporary changes in local stress field and induced seismicity at Krafla caldera, Iceland
摘要
Induced seismicity related to fluid injection in the upper crust is a major concern in the context of geothermal energy production. For exploited high-temperature geothermal systems in tectonically and volcanically active areas, such as Krafla caldera in NE Iceland, understanding the processes that trigger seismicity and changes in the local stress field can be difficult to unravel. We observe a link between anthropogenic activity and changes in the local stress field, since the appearance of a strike-slip cluster coincides with changes in the seismic anisotropy around an injection well during an injection interruption period. By analyzing the shear-wave splitting phenomenon, 90