Core Logging

The AWI Bremerhaven owns equipment to measure physical properties of both whole and split sediment cores. Additionally equipment for color scans of split cores is available.

The physical properties of whole sediment cores (gravity cores and box cores) are measured in one-meter sections using a GEOTEK ‘Multi-Sensor-Core-Logger’ (MSCL). P-wave travel times, magnetic susceptibility, and gamma-ray-absorption are measured simultaneously including control measurements of core diameter and sediment temperature. From these data, the physical properties density, magnetic susceptibility, fractional porosity, p-wave velocity, and impedance can be calculated using the MSCL software package. In addition, measurements of magnetic susceptibility using a Bartington point sensor can be performed on split cores. For practical reasons, the point sensor is often hooked up on the GEOTEK Color-Line-Scan-Logger.

Split-core surfaces are color-scanned with a resolution of 10 to 20 scan lines per millimeter in vertical and 1000 pixels in horizontal direction to have a digital downcore color signal of the fresh sediment. The GEOSCAN camera is used installed on an MSCL array. The camera uses a diachronic color interference filter and three line-scan device arrays (1024 pixels each) to continuously record the three red-green-blue (RGB) color channels.

Physical properties are commonly used for

• lateral core correlation
• localization of distinct layers such as debris flows and turbidites
• distinguishing between regional background sedimentation and locally different sedimentation events and patterns

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