Petrophysical investigation on sediment core CRP-3 from the Ross Sea, Antarctica, supplement to: Jarrard, Richard D (2001): Petrophysics of core plugs from CRP-3 drillhole, Victoria Land Basin, Antarctica. Terra Antartica, 8(3), 143-150

• Main Author: Jarrard, Richard D
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2001
• Subjects: Core wireline system; CRP-3; Sampling/drilling from ice; Cape Roberts Project CRP; Ross Sea; Victoria Land; Cape Roberts; Antarc*; Antarctica; antartic*
• Online Access: https://dx.doi.org/10.1594/pangaea.510758; https://doi.pangaea.de/10.1594/PANGAEA.510758

A suite of petrophysical properties - velocity, resistivity, bulk density, porosity, and matrix density - was measured on 88 core plugs from the CRP-3 drillhole. Core-plug bulk densities were used to recalibrate both whole-core and downhole bulk density logs. Core-plug measurements of matrix density permit conversion of the whole-core and downhole bulk density logs to porosity. Both velocity and formation factor (a normalized measure of resistivity) are strongly correlated with porosity. The velocity/porosity pattern is similar to that for the lower part of CRP-2A and is consistent with the empirical relationship for sandstones. Core-plug and whole-core measurements of P-wave velocity at atmospheric pressure exhibit excellent agreement. Measurements of velocity as a function of pressure indicate a significantly higher velocity sensitivity to pressure than has been observed at CRP-1 and CRP-2A; rebound or presence of microcracks at CRP-3 may be responsible. The percentage difference between velocities at in situ pressures and atmospheric pressures increases downhole from 0% at the seafloor to 9% at the bottom. This pattern can be used to correct whole-core velocity data, measured at atmospheric pressure, to in situ velocities for depth-to-time conversion and associated comparison to the seismic profile across the drillsite