Core samples are collected on land or at sea by the hydrocarbon, mining and construction industries, as well as by the military. For academia they are now an essential part of climatic research. The cores can come as exposed hard rock samples or as soft sediment encased in plastic sleeves. Correctly analysed, they can yield crucial information about the properties of rock or sedimentary strata. The hydrocarbon industry, for example, needs accurate data on the porosity, grain size, type and chemistry of the geology they are investigating, whereas the construction industry and the military may be interested in geotechnical properties such as p-wave velocities, density and water content.
SAMS now has a GeoTek multi-sensor core logger (MSCL) for gathering all these data in an automated and quality-controlled way. The range of parameters that can be measured includes p-wave velocity, gamma density, magnetic susceptibility, electrical resistivity, colour imaging and gamma spectroscopy. These measurements can be used to provide down core information on porosity, grain size and density which change according to deposition and hence environmental conditions over time. Typically, the MSCL can log material at rates of 12 metres per hour and at sampling intervals of down to 1 mm. The machine has now been installed in the SAMS Sediment Laboratory. The MSCL was provided as part of the SAGES initiative (Scottish Alliance of Geosciences, Environment and Society), a collaborative venture between the Universities of Edinburgh, St Andrews, Glasgow, Dundee, Aberdeen, SUERC and SAMS.