Petrophysical investigations on sediment core CRP-2A from the Ross Sea, Antarctica

Pervasive cementation, particularly in the lower half of the core, has affected many CRP-2A petrophysical parameters:(1) fractional porosities are reduced by about 0.05 - 0.10 in the lower part of the hole;(2) velocity and porosity rebound are much smaller than is usually observed for unconsolidated sediments with burial depths similar to CRP-2A;(3) velocities are unusually insensitive to pressure, suggesting that any exhumation-induced microcracks have been scaled subsequently;(4) the velocity/porosity relationship lacks the characteristic signature of exhumation-induced microcracks;(5) the velocity/porosity relationship changes with depth, indicating downhole increase in consolidation;(6) Vp/Vs ratios of the highest-porosity sediments are unusually low, implying enhancement of framework stiffness.