A set of 24 basaltic samples from Hole 896A was imaged using a backscatter electron detector on a scanning electron microscope. Laboratory compressional-wave velocities were measured at elevated confining pressure for 28 minicores from Hole 896A core. Digital image analysis was used to distinguish total areas of plagioclase, olivine, and pyroxene as well as pores + alteration. Results of image processing qualitatively explain why samples with similar total porosity have markedly different compressional-wave velocity. Velocities and densities of Hole 896A samples were compared with laboratory results from the upper part of Hole 504B. Hole 896A samples tend to have lower velocities for a given bulk density than Hole 504B samples, probably a result of different pore structures of rocks from the two sites.
Date of initial receipt:15 August 1994
Date of acceptance: 13 March 1995
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