| This indicates that there existed a short period of radiolarian development before the great extinction at the Permian-Triassic transition. |
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| Subsequently the massive sulfide deposit and surrounding metalliferous sediment apron were covered by oceanic radiolarian chert sediments. |
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| The sequence includes tuffaceous sandstone, andesitic sandstone and radiolarian chert. |
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| They are found in the northern part of the AFERNOD zone and are associated with clayey radiolarian silts. |
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| Silicon is used as a structural material in the diatom shell, the radiolarian and heliozoan spicule, and the chrysophyte exoskeleton. |
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| Polymetallic nodules are preferentially associated with radiolarian silt belonging in part to the recent Quaternary. |
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| Twenty-two samples for radiolarian research were collected from the grayish black, thin-bedded limestone and siliceous limestone of the Baoqing Member and the Mcishan Member. |
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| This contradiction cannot be resolved at present due to a lack of Cambrian radiolarian studies, which are needed to provide chronostratigraphic corroboration. |
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| Calcareous oozes are common in the low and mid-latitudes while in other places, particularly the high latitudes, radiolarian oozes tend to dominate. |
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| Red or brown radiolarian ooze is found along the zone of the Pacific North Equatorial Current, east of longitude 170° W, and on the floors of some deep Indonesian basins. |
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| Geological mapping identified possible pillow basalts beneath a sequence of haematitic, cherty mudstones and radiolarian cherts. |
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| The foraminiferan and radiolarian amoebae have evolved multiple fission. |
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| It is formed of pelagic sediments, varying in thickness from 30 to 50 m. These sediments are composed principally of brown radiolarian silts with a very high level of silica. |
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| Silica-containing material, such as radiolarian and diatom ooze, is found at greater depths, but even these siliceous remains are dissolved at very great depths, where the characteristic deposit is red clay. |
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| Below 4,000 m, calcium carbonate tends to dissolve, and the principal sediment constituents are brown clays and the siliceous remains of radiolarian zooplankton and such phytoplankton as diatoms. |
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