Seismic array classified until the 1990s. Today they become part of the IMS as primary or auxiliary stations. Seismic arrays are not only used to monitor earthquakes and nuclear tests, but also used as a tool for investigating nature and source regions of microseisms as well as locating and tracking volcanic tremor and analyzing complex seismic wave-field properties in volcanic areas. Seismic arrays can be classified by size, which is defined by the array's aperture given by the largest distance between the single seismometers. The sensors in a seismic array are arranged in different geometry patterns horizontally. The arrays built in the
Seismic attribute AVO gradient, intercept multiplied by gradient, far minus near, fluid factor, etc. The anelastic attenuation factor (or Q) is a seismic attribute that can be determined from seismic reflection data for both reservoir characterisation and advanced seismic processing. A post-stack attribute that measures the continuity between seismic traces in a specified window along a picked horizon. It can be used to map the lateral extent of a formation. It can also be used to see faults, channels or other discontinuous features. Although it should be used along a specified horizon, many software packages compute this attribute along arbitrary time-slices. A