(Table T1) Lithology, structure and significant components of sediments from ODP Holes 173-1068A and 173-1069A
Thin sections of samples were studied from (syn-?) postrift sediments of the Iberia Abyssal Plain (Ocean Drilling Program Leg 173, Sites 1068 and 1069). They show that, at these sites, Lower Cretaceous calcareous chalks and calcareous mass-flow deposits are overlain by sub-calcite compensation depth...
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Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2001
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Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.787794 https://doi.org/10.1594/PANGAEA.787794 |
Summary: | Thin sections of samples were studied from (syn-?) postrift sediments of the Iberia Abyssal Plain (Ocean Drilling Program Leg 173, Sites 1068 and 1069). They show that, at these sites, Lower Cretaceous calcareous chalks and calcareous mass-flow deposits are overlain by sub-calcite compensation depth pelagic claystones of Late Cretaceous to early Tertiary age. At both sites, turbidites and current-controlled sequences are intercalated with pelagic claystones and show similar variations: (1) the proportion of turbidites to pelagic clay varies systematically and (2) turbidite composition changes from relatively coarse-grained and calcareous to predominantly fine-grained siliciclastic. This facies transition occurs around the Paleocene/Eocene boundary. In addition, turbidites at the Cretaceous/Tertiary and the Paleocene/Eocene boundaries contain resedimented glauconite, and, occasionally, some pyrite. |
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