Lithofacies, chronostratigraphy, minerals and diagenetic silica facies at DSDP Leg 80 Holes ...
X-ray powder diffraction and optical and scanning-electron microscope analyses of sediment samples taken from four sites drilled in the Goban Spur area of the northeast Atlantic show variable diagenetic silicification of sediments at several stratigraphic horizons. The results are as follows:1. The...
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| Format: | Article in Journal/Newspaper |
| Language: | English |
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PANGAEA
1985
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| Online Access: | https://dx.doi.org/10.1594/pangaea.808220 https://doi.pangaea.de/10.1594/PANGAEA.808220 |
| Summary: | X-ray powder diffraction and optical and scanning-electron microscope analyses of sediment samples taken from four sites drilled in the Goban Spur area of the northeast Atlantic show variable diagenetic silicification of sediments at several stratigraphic horizons. The results are as follows:1. The silicified sediments are middle Eocene at Site 548, Paleocene to lower Albian at Site 549, upper to lower Paleocene at Site 550, and lower Turanian at Site 551.2. There are three types of these silicified sediments: nodular type in carbonate-rich host sediments, bedded type in clayey host sediments, and a type transitional between the other two.3. Silica diagenesis is considered to progress as follows: dissolution of siliceous fossils; precipitation of opal CT in pore spaces and transformation of biogenic silica (opal A) to opal CT, development of opal CT cement; chalcedonic quartz precipitation in pore spaces and replacement of foraminiferal tests by chalcedonic quartz; and finally, transformation of opal CT to ... : Supplement to: Otsuka, Kenichi (1985): Silicified sediments and silica diagenesis in the Goban Spur area of the Northeast Atlantic, Leg 80. In: De Graciansky, PC; Poag, CW; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Gov. Printing Office), 80, 1081-1099 ... |
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