(Table T1) Density, porosity, void ratio and silica crystallinity index of ODP Site 185-1149 sediments@en

Siliceous pelagic sediments have been known to be crystallographically altered during burial diagenesis (e.g., Hesse, 1990; Behl and Smith, 1992, doi:10.2973/odp.proc.sr.129.112.1992). In order to know the systematic downhole change of silicification, sediments from Pacific Ocean crust obtained during Ocean Drilling Program Leg 185 Site 1149 (Plank, Ludden, Escutia, et al., 2000, doi:10.2973/odp.proc.ir.185.2000) were analyzed. For collected samples of Early Cretaceous age below the pelagic sediments, which are not as highly silicified, silica mineral crystallization in the siliceous sedimentary rocks is determined by X-ray diffraction (XRD), and the related textural change is shown by using scanning electron microscope (SEM).