Characterization of 4D-Geophysical Data Using a Nonlinear Inversion Algorithm.

摘要

Characterization of time-lapse 3D seismic data, also known as 4D seismic is based on a difference image of the subsurface from two comparable surveys denoted by the reference state and the monitor state, respectively. Both states are separated by a certain time span. Then from this difference observation, conclusions are drawn with respect to the change of the medium, which can be related to geomechanical and generally structural changes of the subsurface. In this sense the inversion of time-lapse data could be used to forecast the stress-change of hydrocarbon reservoirs due to oil- and gas-production for instance. More generally every time-lapse survey, no matter if it is based on seismic, electromagnetic, or other geophysical measurements, can serve to monitor the man-made and environmentally induced impact to changes of the subsurface geology.