SEGJ Technical Conference

Detailed imaging of the near-surface structure beneath a levee system by means of integrated geophysical investigations.

Abstract Near-surface integrated geophysical surveys were conducted along a levee system which intersected an inferred active fault which reactivated in 1611. We adopted Land Streamer SH seismic reflection survey, hybrid surface-wave survey in addition to DC resistivity measurements along the levee. Tomography measurements and surface geophysical mapping were also carried out before and after partial excavation of the levee in collaboration with an SEGJs task force. A migrated depth section obtained through ordinary data processing flow clearly imaged an eastward dipping structure at the shallow depths, and faulted structure at the inferred portion where resistivity varied suddenly. The survey results demonstrated the usefulness of integrated geophysical survey for the identification of longitudinal heterogeneity of the substrata in small scale.