Design and application of a new free fall in situ resistivity probe for marine deep water sediments

摘要

We have developed a new type of sedimentpenetrating in situ probe which logs electrical resistivity in marineand limnic sediments in the uppermost 3.5m. As the instrument isfitted to a Lister-type heat-flow instrument, combined thermal andelectrical conductivity measurements are possible. The probeincorporates no moving mechanical parts, is built to operate inwater-depths up to 4000 m and relatively easy to deploy. Twoseparate electrode arrays provide for an instant repeatability testand rapid data quality assessment. The probe was extensively testedin the laboratory. Field tests in Lake Konstanz and in the North Seaproduced consistent results. This paper gives a description of thedesign of the probe and the test results. A theoretical derivation ofthe probe's configuration factor is presented and theoretical resultsare verified in laboratory tests.