Kaiser effect (material science) Kaiser effect (material science) The Kaiser effect is a phenomenon observed in geology and material science that describes a pattern of acoustic emission or seismicity in a body of rock or other material subjected to repeated cycles of mechanical stress. In material that exhibits an initial seismic response under a certain load, the Kaiser effect describes the absence of acoustic emission or seismic events until that load is exceeded. The Kaiser effect results from discontinuities (fractures) created in material during previous steps that do not move, expand, or propagate until the former stress is exceeded. Induced seismicity associated with fluid
Vertical seismic profile Vertical seismic profile In geophysics, vertical seismic profile (VSP) is a technique of seismic measurements used for correlation with surface seismic data. The defining characteristic of a VSP (of which there are many types) is that either the energy source, or the detectors (or sometimes both) are in a borehole. In the most common type of VSP, Hydrophones, or more often geophones or accelerometers, in the borehole record reflected seismic energy originating from a seismic source at the surface. There are numerous methods for acquiring a vertical seismic profile (VSP). Zero-offset VSPs (A) have sources close to the wellbore directly