georefid:2008-128961SEDIS Publication Catalogue

ana.macario@awi.de

http://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.2113/gscpgbull.56.2.692008-01-01publicationgeorefid:2008-128961doi:10.2113/gscpgbull.56.2.69Hiscott, Richard N.Memorial University, Earth Sciences Department, St. John's, NL, CanadaauthorMarsaglia, Kathleen M.California State University, Northridge, United StatesauthorWilson, R. Chris L.Open University Milton Keynes, United KingdomauthorRobertson, Alastair H. F.University of Edinburgh, United KingdomauthorKarner, Garry D.ExxonMobil Upstream Research Company, United StatesauthorTucholke, Brian E.Woods Hole Oceanographic Institution, United StatesauthorPletsch, ThomasBundesanstalt fuer Geowissenschaften und Rohstoffe, Federal Republic of GermanyauthorPetschick, RainerJohann Wolfgang Goethe Universitaet, Federal Republic of GermanyauthorCanadian Society of Petroleum Geologists, Calgary, AB, CanadapublisherdocumentHardcopyBulletin of Canadian Petroleum Geology56 (2)69-92The young narrow arm of the Atlantic Ocean that separated Newfoundland from Iberia in the Albian-Cenomanian accumulated a thick succession of muddy gravity flow deposits that were recovered by drilling at Ocean Drilling Program Site 1276 off the Grand Banks of Newfoundland. The sediment thickness and sand content are somewhat surprising given the number of contemporaneous shelf and slope basins that would have acted as traps for detritus shed from the Newfoundland margin. A set of individual studies was undertaken to trace the source of this detritus and to test hypotheses that the material might have been derived, in part, from the east (Iberia), the north (Flemish Cap and northern rift extensions), and/or from various sources to the west (Grand Banks, Interior Newfoundland, Avalon Uplift). By synthesizing seismic data, paleocurrent data from gravity flow deposits, sediment composition (sand detrital modes, clay mineralogy) and detrital mica ages we conclude that the likely source of the Albian-Cenomanian sediment was the Avalon Uplift, situated in the southern Grand Banks. Key pieces of evidence that lead us to this result are: thinning of the sediment package towards the north and thickening towards the southwest, the paleocurrent directions apparently suggesting a southwesterly source, the low proportion of potassium feldspar in the sandstones, and the lack of palygorskite in the shales as compared to Iberian-sourced successions. The apparent inconsistency of detrital mica ages from these deposits, suggesting an Iberian (Hercynian) source with age 270-340 Ma, is attributed to the localization of rifting along a Paleozoic continental suture zone, the Hercynian Front. This tectonic front separates distinctly different geologic units (domains) on the conjugate margins. Such a suture would have generated a significant peripheral foreland basin across the now-submerged shelf regions of Newfoundland allowing transfer of sediment from the Iberian to the Newfoundland domains. Upon Mesozoic rifting and uplift, these mica-bearing sediments from the foreland basin succession could have been reworked and shed eastward into the nascent Atlantic Ocean basin at ODP Site 1276. Alternatively, Hercynian metamorphism and deformation might have extended onto what is now the southeastern Grand Banks, so that young detrital micas could have been derived directly from the Avalon Uplift. Results from this work are relevant to an assessment of sandstone distribution in parts of the Salar Basin and the expected diagenetic overprint for sandy reservoir facies.completedStratigraphyEconomic geology, geology of energy sourcesAlbianAtlantic OceanAvalon UpliftbasinsCenomanianchemical compositionclastic rocksclastic sedimentsCretaceousdeformationdetritusdiagenesisEuropefabricforeland basinsgeophysical methodsgeophysical profilesgeophysical surveysIberian PeninsulaJeanne d'Arc BasinLeg 210lithofaciesLower Cretaceousmarine environmentMesozoicmetamorphismNewfoundland BasinNorth AtlanticobservationsOcean Drilling ProgramODP Site 1276paleogeographypetroleumprestack migrationprovenancereservoir rocksSalar Basinsandsandstonesedimentary rockssedimentationsedimentsseismic methodsseismic migrationseismic profilesshelf environmentslope environmentSouthern EuropesurveysthicknessUpper Cretaceousurn:org.iodp:exp:210urnlargerWorkCitationcampaignurn:org.iodp:exp:210:site:1276urnlargerWorkCitationstudyurn:org.iodp:exp:210urnlargerWorkCitationcampaignEnglishgeoscientificInformation-45.0000-44.200045.100045.3000