Geophysical measurements on sediment cores and geoacoustic modeling

Abstract

Geophysical measurements on marine sediments cores have considerable interest and importance in underwater acoustics and marine geophysics. A series of studies on geoacoustic properties of marine sediments have been conducted and modeled on the samples from Australian continental shelves by the technique developed by UNSW. More works were carried out on cores from North Atlantic ocean basins at the Alfred Wegner Institute in Germany by using a multisensor core logger (MSCL). MSCL is a logging device which enables a number of geophysical measurements such as p-wave velocity, gamma ray attenuation, and magnet susceptibility on marine sediment cores encased in cylindrical plastic core liners. A pair of compressional wave transducers at 250 kHz is used to measure dilatational velocity and a gamma ray source and detector are used to measure attenuation in the cores. A comparative study of physical properties measured by a MSCL system and UNSW technique has been applied to a wide range of frequencies and modeled with modified Biot–Stoll theory.