Figure F6. Single-polarized thin section photomicrographs displaying cement types and dissolution features, Site U1373. Orange arrows point toward top. Preliminary cement classification and interpretations of depositional environment are based on Flügel (1982). A. Grainstone in Subunit IIIA with (1) mold of dissolved shell fragment outlined by thin micrite envelope, (2) sparite cement partially filling mold, (3) remaining void, and (4) partly micritized cement, possibly resulting from biogenic activity (Sample 330-U1373A-3R-3, 86–89 cm; Thin Section 85). B. Grainstone in Subunit IIIB with (1) fibrous meniscus cement and (2) voids (Sample 330-U1373A-4R-1, 72–74 cm; Thin Section 84). This cementation pattern supports an intertidal deposition environment. C. Grainstone in Subunit IIIC with (1) micrite (possibly meniscus cement), (2) dogtooth and granular cements, and (3) dissolved shell fragment (Sample 330-U1373A-5R-1, 33–36 cm; Thin Section 86). Meniscus and dogtooth cements indicate cementation in a vadose environment. D. Geopetal structure in Subunit IIIC (Sample 330-U1373A-5R-1, 33–36 cm; Thin Section 86). Mollusk shell includes (1) two layers of vadose silt, (2) dogtooth cement, and (3) granular cement. Vadose silt and dogtooth cement indicate cement precipitation in vadose environments. E. Grainstone in Subunit IIIC with (1) micrite with possible meniscus texture, (2) rim cement, and (3) granular cement, in order of generation (Sample 330-U1373A-5R-1, 101–104 cm; Thin Section 87). F. Grainstone with dripstone cement (Sample 330-U1373A-5R-1, 33–36 cm; Thin Section 86). Sparite cements concentrated on lower part of grains indicate precipitation in a vadose environment.
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