georefid:2000-045702SEDIS 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=2000-0457022000-01-01publicationgeorefid:2000-045702Zuffa, G. G.Universita di Bologna, Dipartimento di Scienze della Terra, Bologna, ItalyauthorNormark, W. R.U. S. Geological Survey, United StatesauthorSerra, F.University of Southern Mississippi, United StatesauthorBrunner, C. A.authorUniversity of Chicago Press, Chicago, IL, United StatespublisherdocumentHardcopyJournal of Geology108 (3)253-274Escanaba Trough is the southernmost segment of the Gorda Ridge and is filled by sandy turbidites locally exceeding 500 m in thickness. New results from Ocean Drilling Program (ODP) Sites 1037 and 1038 that include accelerator mass spectrometry (AMS) (super 14) C dates and revised petrographic evaluation of the sediment provenance, combined with high-resolution seismic-reflection profiles, provide a lithostratigraphic framework for the turbidite deposits. Three fining-upward units of sandy turbidites from the upper 365 m at ODP Site 1037 can be correlated with sediment recovered at ODP Site 1038 and Deep Sea Drilling Program (DSDP) Site 35. Six AMS (super 14) C ages in the upper 317 m of the sequence at Site 1037 indicate that average deposition rates exceeded 10 m/k.yr. between 32 and 11 ka, with nearly instantaneous deposition of one approximately 60-m interval of sand. Petrography of the sand beds is consistent with a Columbia River source for the entire sedimentary sequence in Escanaba Trough. High-resolution acoustic stratigraphy shows that the turbidites in the upper 60 m at Site 1037 provide a characteristic sequence of key reflectors that occurs across the floor of the entire Escanaba Trough. Recent mapping of turbidite systems in the northeast Pacific Ocean suggests that the turbidity currents reached the Escanaba Trough along an 1100-km-long pathway from the Columbia River to the west flank of the Gorda Ridge. The age of the upper fining-upward unit of sandy turbidites appears to correspond to the latest Wisconsinan outburst of glacial Lake Missoula. Many of the outbursts, or jokulhlaups, from the glacial lakes probably continued flowing as hyperpycnally generated turbidity currents on entering the sea at the mouth of the Columbia River.completedQuaternary geologyabsolute ageacoustical methodsC-14carbonCenozoicclastic sedimentsColumbia RivercorrelationdatesDeep Sea Drilling ProjectDSDP Site 35East PacificEscanaba TroughForaminiferageophysical methodsgeophysical profilesgeophysical surveysglacial featuresglacial lakesGorda Riseheavy mineralshigh-resolution methodsInvertebrataisotopesjokulhlaupsLake MissoulalakesLeg 169Leg 5lithostratigraphymagnetic susceptibilitymarine sedimentsNorth PacificNortheast PacificOcean Drilling ProgramODP Site 1037ODP Site 1038Pacific Oceanpaleomagnetismphysical propertiesPleistoceneProtistaprovenanceQuaternaryradioactive isotopesreflection methodsrift zonessandsediment transportsedimentationsedimentation ratessedimentsseismic methodsseismic profilesseismic stratigraphysurveysturbiditeUnited Statesupper Pleistoceneupper WisconsinanvolcaniclasticsWestern U.S.Wisconsinanurn:org.iodp:exp:169urnlargerWorkCitationcampaignurn:org.iodp:exp:5urnlargerWorkCitationcampaignurn:org.iodp:exp:5:site:35urnlargerWorkCitationstudyurn:org.iodp:exp:5urnlargerWorkCitationcampaignurn:org.iodp:exp:169:site:1037urnlargerWorkCitationstudyurn:org.iodp:exp:169urnlargerWorkCitationcampaignurn:org.iodp:exp:169:site:1038urnlargerWorkCitationstudyurn:org.iodp:exp:169urnlargerWorkCitationcampaignEnglishgeoscientificInformation-127.3000-127.300040.300041.1000