georefid:1981-027017georefid:1981-026994SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.2973/dsdp.proc.55.123.1980<gco:CharacterString>Leg 55, Emperor Seamounts; trace elements in transitional tholeiites, alkali basalts, and hawaiites; mantle homogeneity or heterogeneity and magmatic processes</gco:CharacterString>1980-01-01publicationgeorefid:1981-027017doi:10.2973/dsdp.proc.55.123.1980Cambon, P.Cent. Oceanol. Bretagne, Brest, FranceauthorJoron, J. L.authorBougault, H.authorTreuil, M.authorTexas A & M University, Ocean Drilling Program, College Station, TX, United StatespublisherdocumentDigitalIn: Shambach, James (editor), Jackson, Everett Dale, Koizumi, Itaru, Avdeiko, Gennady, Butt, Arif, Clague, David, Dalrymple, G. Brent, Greene, H. Gary, Karpoff, Anne Marie, Kirkpatrick, R. James, Kono, Masaru, Hsin Yi Ling, McKenzie, Judith, Morgan, Jason, Takayama, Toshiaki, Initial reports of the Deep Sea Drilling Project covering Leg 55 of the cruises of the drilling vessel Glomar Challenger, Honolulu, Hawaii to Yokohama, Japan; July-September 197755585-597According to the classification of the elements which was made previously from the samples recovered in the Atlantic Ocean, with regard to their physicochemical properties and partition coefficients, the following items can be formulated from the study of the Emperor Seamount samples drilled during Leg 55: 1) The chondritic nature of the "primordial" mantle is confirmed through Y/Tb, Zr/Hf, and Nb/Ta ratios. 2) The value 9 for the La/Ta ratio has been found related to topographic highs or platforms in the Atlantic Ocean (the value is 18 in other cases, corresponding to typically "depleted" tholeiites). The values close to 9 found for Emperor Seamount samples independently of their petrographic classification (tholeiite, alkali basalts, or hawaiite) tend to confirm the correlation of this ratio to topography. 3) The single Th/Ta ratio observed in tholeiites, alkali basalts, and hawaiites suggests similar mantle sources for these different rock types. 4) The transition elements belonging to the same series, characterized by different partition coefficients, show a fractionation. This fractionation can be interpreted as the result of partial melting. 5) Ti and V are fractionated in hawaiites as a consequence of titanomagnetite crystallization.completedGeochemistryalkalic compositionbasaltsDeep Sea Drilling ProjectEmperor Seamountsfractional crystallizationfractionationgeochemistryhowaiitesigneous processesigneous rocksIPODLeg 55mantleNorth PacificNorthwest PacificPacific Oceanpetrologyphysicochemical propertiesprocessesSite 430Site 432Site 433tholeiitestrace elementsvolcanic rocksWest Pacificurn:org.iodp:exp:55urnlargerWorkCitationcampaignurn:org.iodp:exp:55:site:430urnlargerWorkCitationstudyurn:org.iodp:exp:55urnlargerWorkCitationcampaignurn:org.iodp:exp:55:site:432urnlargerWorkCitationstudyurn:org.iodp:exp:55urnlargerWorkCitationcampaignurn:org.iodp:exp:55:site:433urnlargerWorkCitationstudyurn:org.iodp:exp:55urnlargerWorkCitationcampaignEnglishgeoscientificInformation160.0000175.000035.000050.0000application/pdfunknownSEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContacthttp://deepseadrilling.org/55/volume/dsdp55_23.pdfdownload