Epigenesis of sediments in the Cascadia accretionary prism, western continental margin of United States

Author(s): Chamov, N. P.; Kurnosov, V. B.
Author Affiliation(s): Primary:
Russian Academy of Sciences, Geological Institute, Moscow, Russian Federation
Volume Title: Lithology and Mineral Resources
Source: Lithology and Mineral Resources, 36(5), p.445-459. Publisher: MAIK Nauka/Interperiodica Publishing, Birmingham, AL, United States. ISSN: 0024-4902 CODEN: LTMRAR
Note: In English. 22 refs.; illus., incl. 2 tables
Summary: Upper Miocene to Holocene sediments from the Cascadia accretionary prism and its oceanic surroundings drilled during ODP Leg 146 are studied in order to reveal their alteration during the accretion. The conclusion is made that methane-bearing solutions play a leading role in the transportation of material and the formation of mineralogical-geochemical zonality within the prism. A considerable intensity and high rates of epigenetic alteration are noted. It is shown that low heat flow, absence of progressive subsidence of the accretionary prism, open character of the system relative to water circulation, and heterogeneity of the sedimentary sequence hindered the successive development of epigenesis.
Year of Publication: 2001
Research Program: ODP Ocean Drilling Program
Key Words: 06 Petrology, Sedimentary; 07 Marine Geology and Oceanography; Accretionary wedges; Aliphatic hydrocarbons; Alkanes; Alteration; Cascadia Basin; Cenozoic; Chemical composition; Clastic sediments; Clay minerals; Compression tectonics; Concentration; Continental margin; East Pacific; Faults; Fracture zones; Geochemistry; Holocene; Hydrocarbons; Leg 146; Marine sediments; Methane; Mineral composition; Miocene; Neogene; North Pacific; Northeast Pacific; ODP Site 888; ODP Site 889; ODP Site 890; ODP Site 891; ODP Site 892; Ocean Drilling Program; Ocean circulation; Organic compounds; Pacific Ocean; Petrography; Petrology; Provenance; Quaternary; Sand; Sedimentary rocks; Sediments; Sheet silicates; Silicates; Silt; Solutions; Subduction zones; Tectonics; Tertiary; Transformations; United States; Upper Miocene
Coordinates: N480959 N481001 W1263943 W1263948
N484151 N484159 W1265206 W1265223
N483945 N483945 W1265253 W1265253
N443838 N443840 W1251932 W1251934
N444026 N444032 W1250705 W1250709
Record ID: 2002025557
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