Robertson, Alastair H. F. (2007): Geochemical evidence for the sedimentary and diagenetic development of the Mesozoic-early Cenozoic Newfoundland rifted margin, Northwest Atlantic (Ocean Drilling Program Leg 210, Site 1276)

Leg/Site/Hole:
ODP 210
DSDP 47
DSDP 47 398
ODP 210 1276
Identifier:
2007-087761
georefid

10.2973/odp.proc.sr.210.105.2007
doi

Creator:
Robertson, Alastair H. F.
University of Edinburgh, Grant Institute of Earth Science, Edinburgh, United Kingdom
author

Identification:
Geochemical evidence for the sedimentary and diagenetic development of the Mesozoic-early Cenozoic Newfoundland rifted margin, Northwest Atlantic (Ocean Drilling Program Leg 210, Site 1276)
2007
In: Tucholke, Brian E., Sibuet, Jean-Claude, Klaus, Adam, Arnaboldi, Michela, Delius, Heike, Engstrom, Anna V., Galbrun, Bruno, Gardin, Silvia, Hiscott, Richard N., Karner, Garry D., Ladner, Bryan C., Leckie, R. Mark, Lee, Chao-Shing, Manatschal, Gianreto, Marsaglia, Kathleen M., Pletsch, Thomas K., Pross, Joerg, Robertson, Alastair H. F., Sawyer, Dale S., Sawyer, Derek E., Shillington, Donna J., Shirai, Masaaki, Shryane, Therese, Stant, Sharon Audra, Takata, Hiroyuki, Urquhart, Elspeth, Wilson, Chris, Zhao, Xixi, Proceedings of the Ocean Drilling Program; scientific results; drilling the Newfoundland half of the Newfoundland-Iberia transect; the first conjugate margin drilling in a nonvolcanic rift; covering Leg 210 of the cruises of the Drilling Vessel JOIDES Resolution; St. Georges, Bermuda, to St. John's, Newfoundland; sites 1276 and 1277; 6 July-6 September 2003
Texas A&M University, Ocean Drilling Program, College Station, TX, United States
210
Inorganic chemical composition and downhole variation of major and trace elements yields useful insights into the sediment provenance and paleoceanography of deep-sea sediments of deepwater continental margins. Here, fine-grained sediments were chemically analyzed at approximately 10-m intervals from the Eocene to Albian section at Site 1276. These sediments represent a time when background hemipelagic sedimentation was continuously beneath, or near, the calcite compensation depth (CCD). Additional samples were analyzed from the upper Paleocene-middle Eocene time interval to determine whether a volcaniclastic component is present, as suggested by petrographic studies of the coarser size fraction. Sediments recovered near the bottom of the hole show the effects of contact metamorphism adjacent to a sill of alkaline basalt. The overlying thick ( approximately 700 m) Albian succession (lithologic Unit 5) is indicative of a dominantly terrigenous source. Redox-sensitive trace elements (e.g., Cu, Ni, V, and Cr) are concentrated in organic-rich layers (black shales) that can be partially correlated with oceanic anoxic Events 1a-1d and 2. Beginning around the Cenomanian/Turonian boundary, a profound change took place to more oxidizing, slowly depositing sediments throughout the North Atlantic, characterized by relative enrichment in Fe, Mn, and related trace metals (e.g., Cu, Ni, and Cr). Similar background conditions persisted until the Eocene when local conditions at Site 1276 became more reducing, as indicated by more subdued colors and lower MnO contents. Moderate upwelling along the Newfoundland continental margin during the Eocene is suggested by the presence of relatively high values of silica coupled with opaline silica. Phosphate and associated trace elements (e.g., Ce and Y) are locally enriched, suggesting relatively high primary productivity. However, productivity was lower than on the conjugate Iberia margin at Deep Sea Drilling Project Site 398. Fine-grained terrigenous sediments at Site 1276 probably were mainly derived from the Grand Banks (e.g., Avalon uplift) and finally accumulated in deep water below the CCD mainly as mud turbidites and hemipelagites.
English
Coverage:Geographic coordinates:
North:45.2400
West:-44.4700East: -44.4700
South:45.2400

Stratigraphy; Geochemistry of rocks, soils, and sediments; Applied geophysics; Atlantic Ocean; black shale; Canada; Cenozoic; chemical composition; chemical ratios; chemostratigraphy; clastic rocks; continental margin; cores; Cretaceous; Deep Sea Drilling Project; depositional environment; diagenesis; DSDP Site 398; Eastern Canada; Europe; Flemish Cap; geochemistry; geophysical methods; geophysical profiles; geophysical surveys; Grand Banks; Iberian Peninsula; IPOD; Leg 210; Leg 47; lithostratigraphy; major elements; marine environment; Mesozoic; Newfoundland; Newfoundland and Labrador; North Atlantic; Northwest Atlantic; Ocean Drilling Program; ODP Site 1276; paleo-oceanography; paleoenvironment; Paleogene; paleogeography; plate tectonics; provenance; rifting; sedimentary rocks; seismic methods; seismic profiles; seismic stratigraphy; Southern Europe; spatial variations; spectra; surveys; terrigenous materials; Tertiary; trace elements; X-ray fluorescence spectra;

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