Cristobalitic stage in the diagenesis of diatomaceous shale

K. J. Murata; J. K. Nakata

doi:10.1126/science.184.4136.567

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Cristobalitic stage in the diagenesis of diatomaceous shale

K. J. Murata·J. K. Nakata

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Abstract

With increasing depth of burial, diagenetic cristobalite in the Monterey Shale of California shows a decrease in the d (101) spacing from 4.115 to 4.040 angstroms, indicative of a progressive change in its internal structure. The spacing is 0.004 to 0.015 angstrom smaller in porcellanite than in associated chert, probably because the cristobalite of porcellanite formed later than that of chert.

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Source-reported bounding extent: 32.550398524822015° to 42.010359415361904° latitude; -124.63205839049° to -114.18927435843364° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K. J. Murata, J. K. Nakata. 1974. Cristobalitic stage in the diagenesis of diatomaceous shale. https://doi.org/10.1126/science.184.4136.567

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