The transition of olivine to spinel may cause the "deep focus" type of these events.
These events can be caused by the hydraulic stimulation of HDR in the EGS system of power generation. The transition of olivine to spinel may cause the "deep focus" type of these events. They occur along an inclined angle at subduction zones in areas called Wadati-Benioff zones. Instruments to measure these events record arrival times of S-  and P-waves, the difference in which can be used to calculate the location of their epicenters. If they occur near water, they may cause a tsunami. For 10 points, name these events whose intensity is measured on the Richter scale.
These events can be caused by the hydraulic stimulation of HDR in the EGS system of power generation.
earthquakes [or tremor; or temblor; prompt on seismic activity]