NONDESTRUCTIVE DENSITY DETERMINATION ON MARINE SEDIMENT CORES FROM GAMMA-RAY ATTENUATION MEASUREMENTS

We describe an improved nondestructive technique for density measureme nt based on gamma-ray absorption that permits construction of high-res olution density profiles of marine sediment cores. The system is capab le of resolving vertical density variations with a spatial resolution of 4 mm and absolute accuracy of +/-1%. Comparison with conventional d ensity determination on samples confirms the absolute accuracy. In add ition to standard vertical profiling, a core rotation option is includ ed to measure density as a function of rotation angle. This allows the quantification of the variability of density within a layer and detec tion of inhomogenities like ice-rafted debris or biogenic structures.