Seismic intensity scales Seismic intensity scales Seismic intensity scales categorize the intensity or severity of ground shaking (quaking) at a given location, such as resulting from an earthquake. They are distinguished from seismic magnitude scales, which measure the magnitude or overall strength of an earthquake. Intensity scales are based on the observed effects of the shaking, such as the degree to which people or animals were alarmed, and the extent and severity of damage to different kinds of structures or natural features. The maximal intensity observed, and the extent of the area where shaking was felt (see isosiesmal map, below), can be used
Seismic Unix Seismic Unix Seismic Unix is an open source seismic utilities package supported by the Center for Wave Phenomena (CWP) at the Colorado School of Mines (CSM). Einar Kjartansson began writing what is now called SU (the SY package) in the late 1970s while still a graduate student at Jon Claerbout's Stanford Exploration Project (SEP). He continued to expand the package while he was a professor at the University of Utah in the early eighties. In 1984, during an extended visit to SEP Einar introduced SY to Shuki Ronen, then a graduate student at Stanford. Ronen further developed SY from 1984