A pre dredge study of the Flinders Port, access channel (2005).
After geotechnical studies failed to confirm seismic refraction results, the client elected to carry out an Aquares resistivity survey. A thick caprock layer was found covering a significant portion of the access channel seabed. The lateral and vertical extent of this caprock layer was mapped in detail using the resistivity results of survey lines sailed every 20 m. The results were shown as horizontal and vertical sections extracted from a 3D resistivity model of the entire access channel. A comparison of the resistivity and refraction results are shown here. An Aquares line was run along the same line as a refraction line. The refraction results show a low velocity layer on top of a high velocity base structure, while the resistivity results suggest the opposite: a high resistivity structure on top of low resistivity sediments at depth. The resistivity results were confirmed by drilling and sampling results.
This resulted in the client being provided with a highly accurate analysis of the channel seabed and allowed for greater accuracy in planning and undertaking the project.