georefid:2000-026819SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2000-026819<gco:CharacterString>Pumpellyite from the oceanic crust, DSDP/ODP Hole 504B</gco:CharacterString>1999-01-01publicationgeorefid:2000-026819Ishizuka, H.Kochi University, Department of Geology, Kochi, JapanauthorMineralogical Society, London, United KingdompublisherdocumentHardcopyMineralogical Magazine63 (6)891-900Pumpellyite has been found in doleritic basalt of a sheeted dyke complex drilled from 2072.1 m below sea floor in DSDP/ODP Hole 504B, south of the Costa Rica Rift, eastern Pacific. It occurs as fine-grained crystal aggregates accompanied by albite, chlorite and chalcopyrite, which partially replace a plagioclase phenocryst (An (sub 85-88) ) that is also associated with primary magnetite. Chemical compositions of the pumpellyite vary antithetically in relation to Fe (super *) and Al as well as Fe (super *) and Mg, indicating the dominant substitution of Fe (super 3+) by Al with the minor substitution of Fe (super 2+) by Mg. Such compositional variations overlap with those of prehnite-pumpellyite facies rocks dredged from other oceanic ridges and intra-oceanic arcs, and those of similar facies rocks from ophiolites, but are aluminous compared with those of zeolite facies metabasites in ophiolites. These observations suggest that the breakdown of the plagioclase phenocryst and magnetite in the presence of a Cu- and S-bearing fluid phase led to the formation of pumpellyite + albite + chlorite + chalcopyrite during oceanic ridge hydrothermal alteration.completedMineralogy of silicatesCosta Rica RiftcrustDeep Sea Drilling ProjectDSDP Site 504East Pacifichydrothermal alterationIPODLeg 111Leg 137Leg 140Leg 148Leg 69Leg 70Leg 83Leg 92metasomatismOcean Drilling Programoceanic crustorthosilicatesPacific Oceanpumpellyitepumpellyite groupsilicatessorosilicatesurn:org.iodp:exp:111urnlargerWorkCitationcampaignurn:org.iodp:exp:137urnlargerWorkCitationcampaignurn:org.iodp:exp:140urnlargerWorkCitationcampaignurn:org.iodp:exp:148urnlargerWorkCitationcampaignurn:org.iodp:exp:69urnlargerWorkCitationcampaignurn:org.iodp:exp:70urnlargerWorkCitationcampaignurn:org.iodp:exp:83urnlargerWorkCitationcampaignurn:org.iodp:exp:92urnlargerWorkCitationcampaignurn:org.iodp:exp:69:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:69urnlargerWorkCitationcampaignurn:org.iodp:exp:70:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:70urnlargerWorkCitationcampaignurn:org.iodp:exp:83:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:83urnlargerWorkCitationcampaignurn:org.iodp:exp:92:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:92urnlargerWorkCitationcampaignurn:org.iodp:exp:111:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:111urnlargerWorkCitationcampaignurn:org.iodp:exp:137:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:137urnlargerWorkCitationcampaignurn:org.iodp:exp:140:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:140urnlargerWorkCitationcampaignurn:org.iodp:exp:148:site:504urnlargerWorkCitationstudyurn:org.iodp:exp:148urnlargerWorkCitationcampaignEnglishgeoscientificInformation-85.0000-80.00000.000010.0000