Techniques: Sediment physical properties such as magnetic susceptibility, electric conductivity, sound velocity, and color reflectance are controlled by sediment composition and fabric. With modern logging methods, these parameters can be measurement quantitatively, non-destructively and at high resolution on sediment cores and rock samples. They are of high practical value for the description, stratigraphy and correlation of sediment cores and their comparison with macnetic, seismic and geoelectric sections on land and at sea. We have conducted routine core logging and imaging on board of research vessels and in our own core logging laboratory over the past 30 years and hold competence in reliable data acquisition, analytical and statistical data mining methods and sedimentological and paleooceanographic core log interpretations.
System: This fast-track Multi Sensor Core Logger has been designed for shipboard operation, constructed with MARUM funds, and successfully proven at sea. The stiff modular structure and the compact cable harness facilitate onboard installation. The system is presently equipped with Bartington loop sensors for full- and half-core magnetic susceptibility logging - optionally with 135mm bore (MS2C135) for 10-12cm thick cores or 80mm bore for 6-7cm thick cores and U-channels. The new control unit (MS3) reduces measuring time to 1-3 sec thereby doubling core throughput. The non-contact resistivity (NCR) sensor for porosity measurement now has digital, less noise-sensitive electronics. The innovative drivetrain with two toothed belt conveyors in V-setting allows to log changing core diameters (MEBO, GC, PC) without prior conversion, laser segment length and position control with sub-mm-precision, and bidirectional core transport enabling zero offset correction within segments. The new LabView control software autmates all required data processing steps (drift and core-end correction, deconvolution) and simplifies data control and organization.
System: Our mobile GEOTEK Multi Sensor Core Logger (MSCL) is primarily operated on board of research vessels. It is equipped with a magnetic susceptibility coil sensor (Bartington MS2C, diameter 140 mm, effective resolution of 2 x 10E-6 SI) integrating over a core interval of ca. 8 cm. An additional non-contact resisitivity sensor (NCR) is taken to measure electric conductivity, from which sediment porosity and wet bulk density can be estimated. All individual segment logs are merged into a complete core log, where the immanent core-end signal reduction is compensated by an adapted correction function. The digital RGB line scan camera GEOSCAN II consisting of three 1024 pixel CCD line arrays obtains digital color photographs of the entire split cores surface. A specific image processing program connects the segment images while removing end-caps, cavities and other raw image disturbances prior to further image analysis (e.g. lightness, hue, color ratios).
System: This spectrophotometer determines the diffuse reflectance of rock surfaces in the extended visible light spectrum of 360-740 nm (10 nm intervals) over area of 8 resp. 3 mm (Ã˜). The manual system is useful for the lithostratigraphic analysis of split cores and cube samples, in particular to measure the abundance of pigmented minerals such as hematite, goethite, coal, clay etc. A new endmember modelling technique for such data was developed by our group (Heslop et al. 2007) and used to detect dust and diagenetic layers in sediment cores.