Publication Date:
2023-06-27
Description:
Anisotropy in compressional-wave velocities in sedimentary rocks recovered by DSDP has been recognized by several investigators (Boyce, 1976; Tucholke et al., 1976; Carlson and Christensen, 1977). The anisotropy is also observed at elevated pressures in laboratory experiments, and thus probably persists at depth in some calcareous rocks (Schreiber et al., 1972; Christensen et al., 1973; Carlson and Christensen, 1979). Carlson and Christensen (1979) suggested that the observed velocity anisotropy was produced not by the alignment of cracks but by the alignment of c axes of calcite perpendicular to bedding during compaction, diagenesis, and recrystallization.
On DSDP Leg 62, calcareous rocks were recovered from the western Mid-Pacific Mountains (sub-bottom depths of 452-823 m, Site 463) and southern Hess Rise (276-412 m, Site 465). Most of the calcareous rocks are horizontally laminated and color-banded, and ages are early Cenomanian to late Barremian (Site 463 and 465 reports, this volume).
The purpose of this study is to confirm the velocity anisotropy in the calcareous rocks and to identify any relationship of anistropy to bulk density, mean velocity, and burial depth.
Keywords:
62-463; 62-465A; Comment; Deep Sea Drilling Project; Density, wet bulk; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Event label; Gamma-ray attenuation porosity evaluator (GRAPE); Glomar Challenger; Gravimetric analysis; Hamilton frame velocimeter, Boyce (1976); Leg62; North Pacific/CONT RISE; North Pacific/SEAMOUNT; Sample code/label; Velocity, compressional wave; Velocity, compressional wave anisotropy
Type:
Dataset
Format:
text/tab-separated-values, 579 data points
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