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Delineating a shallow fault zone and dipping bed rock strata using multichannal analysis of surface waves with a land streamer

J. Ivanov·R. D. Miller·P. Lacombe·C. D. Johnson·J.W. Lane
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Abstract

The multichannel analysis of surface waves (MASW) seismic method was used to delineate a fault zone and gently dipping sedimentary bedrock at a site overlain by several meters of regolith. Seismic data were collected rapidly and inexpensively using a towed 30-channel land streamer and a rubberband-accelerated weight-drop seismic source. Data processed using the MASW method imaged the subsurface to a depth of about 20 m "> 20 m 20m and allowed detection of the overburden, gross bedding features, and fault zone. The fault zone was characterized by a lower shear-wave velocity ( V s ) "> ( V s ) (Vs) than the competent bedrock, consistent with a large-scale fault, secondary fractures, and in-situ weathering. The MASW 2D V s "> V s Vs section was further interpreted to identify dipping beds consistent with local geologic mapping. Mapping of shallow-fault zones and dipping sedimentary rock substantially extends the applications of the MASW method.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 40.25437660372649° to 40.27012860983725° latitude; -74.82603549957275° to -74.80174541473389° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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J. Ivanov, R. D. Miller, P. Lacombe, C. D. Johnson, J.W. Lane. 2006. Delineating a shallow fault zone and dipping bed rock strata using multichannal analysis of surface waves with a land streamer. https://doi.org/10.1190/1.2227521

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