1887

### Abstract

Geophysical methods are commonly used to obtain ground condition changes in various application fields. These monitoring of ground condition needs accurate data measurements as well as proper interpretation method to obtain or image the change of the physical property of the subsurface with time. In this study, we extended the three-dimensional (3-D) resistivity imaging algorithm to four-dimensional (4-D) imaging algorithm, where measured resistivity data and geoelectric structure of subsurface is assumed to be 4-D (i.e., 3-D in space and varies with time). To demonstrate the enhanced imaging capability by our new 4-D imaging algorithm, we revisited the 3-D resistivity monitoring data set acquired at the LNG storage pilot plant to delineate the zones of ground condition changes due to cryogenic environment due to the LNG storage. Compared to the conventional time lapse imaging based on the separate inversion of data set acquired at different time of monitoring survey, 4-D inversion algorithm provided much clear image of the change of the ground with much less inversion artifacts, which suggests that our new 4-D imaging algorithm provides more quantitative means to evaluate the change of the ground conditions and their causes.

/content/papers/10.3997/2214-4609.20146228
2008-09-17
2022-08-16