A CT system for the analysis of prehistoric ice cores

The task was to measure ice cores with a diameter of 10 cm and a length of 1 m that were drilled out of Arctic and Antarctic glaciers down to 3,000 m depth. By means of computed tomography (CT), pieces of 1 m length are measured and three-dimensional volume data with high spatial resolution are reconstructed. Complex image processing algorithms are applied to analyze the volume regarding its mean porosity as a function of depth, its total mean porosity and the volumetric distribution of the pores. Since high image quality is required to achieve precise results, a vast amount of data is acquired. The geometry of the samples increases the requirements for the X-ray components. Furthermore measurements have to be made in an environment of -15 C.