Abstract: A method for seismic event mapping includes adaptively velocity filtering seismic signals recorded at selected positions. The velocity filtered signals are transformed into a domain of possible spatial positions of a source of seismic events. An origin in spatial position and time of at least one seismic event is determined from space and time distribution of at least one attribute of the transformed seismic data.
June 16, 2009
Date of Patent:
November 22, 2011
Chuntao Liang, Michael P. Thornton, Peter Morton
Abstract: A method of imaging the Earth's subsurface using passive seismic emissions includes detecting seismic signals originating from within the Earth's subsurface over a selected time period using an array of seismic sensors deployed proximate the Earth's surface. Hypocenters of seismic events in the subsurface are determined from the detected signals. Seismic signals detected at selected ones of the seismic sensors are cross-correlated to signals detected at other selected ones of the seismic sensors. The cross-correlated signals are processed to obtain a reflectivity series at a geodetic position of the selected one of the seismic sensors. A spatial distribution of at least one seismic property in the subsurface is determined using the determined hypocenters and the reflectivity series.
Abstract: A method for seismic event mapping includes selecting a plurality of subvolumes representing possible locations of origin of a seismic event in the Earth's subsurface. For each subvolume a plurality of possible directions of motion of subsurface formations is selected. For each subvolume and each possible direction of motion, polarity correction is applied to seismic signals recorded at a plurality of positions proximate a volume of the Earth's subsurface to be evaluated. The polarity correction is based on the direction of motion and the position of each seismic sensor with respect to the subvolume. The recorded, polarity corrected seismic signal recordings are time aligned. The time aligned recordings are summed. A most likely direction of motion and subvolume position are determined based on a selected attribute of the summed, time aligned seismic signals.
Abstract: A method for seismic event mapping includes transforming seismic signals recorded at selected positions into a domain of possible spatial positions of a source of seismic events. An origin in spatial position and time of at least one seismic event is determined from space and time distribution of at least one attribute of the transformed seismic data.
September 15, 2006
Date of Patent:
February 16, 2010
Peter M. Duncan, James D Lakings, Roderick A. Flores