georefid:2009-026788SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2009-026788<gco:CharacterString>K voprosu o sostave i vozraste magmaticheskikh porod podnyatiya Obrucheva (Tikhiy okean) Problem of composition and age of magmatic rocks of Obruchev Rise (Pacific Ocean)</gco:CharacterString>2000-01-01publicationgeorefid:2009-026788Tararin, I. A.Rossiyskaya Akademiya Nauk, Dal'nevostochnoye Otdeleniye, Tikhookeanskiy Okeanologicheskiy Institut, Vladivostok, Russian FederationauthorKarp, B. Ya.authorNauka, Novosibirsk, Russian FederationpublisherdocumentHardcopyTikhookeanskaya Geologiya = Pacific Geology19 (3)49-54The analysis and critical assessment of data from the literature on the Obruchev Rise, located in the northern termination of the Hawaiian-Emperor volcanic chain, are evidence that the rise is built by strongly altered tholeiitic basaltoids of the shield stage of Hawaiian-type volcanism with a minimal age of 61.9 + or - 5 Ma. This age is in agreement with Maastrichtian (hole 192, Meidzi guyot) and Campanian (hole 883, Detroit Plateau) age of sedimentary rock occurring on the erosion surface of the basal basement. The subalkaline basalts--hawaiites and mugearites, detected by dredging of subordinated craters of the Detroit Plateau, signify the post-shield stage of hawaiian-type volcanism. It is assumed that tholeiitic basalts with an Rb-Sr radioisochrone age of 49.0 Ma, dredged at hole 2649 on the Meidzi guyot, are geochemically distinct from tholeiites of the shield stage of hawaiian type, show a great similarity to the Eocene tholeiites of the complex from the basement of the Attu Island, Aleutian island arc, and may belong to products of glacial delivery.completedIgneous and metamorphic petrologyGeochronologyabsolute ageageAttu IslandbasaltsCretaceousDeep Sea Drilling ProjectDSDP Site 192East PacificEmperor SeamountsHawaiian Ridgeigneous rocksLeg 145Leg 19Mesozoicmid-ocean ridge basaltsNorth PacificNortheast PacificNorthwest PacificObruchev RiseOcean Drilling ProgramODP Site 883Pacific OceanRb/SrUpper Cretaceousvolcanic rocksvolcanismWest Pacificurn:org.iodp:exp:145urnlargerWorkCitationcampaignurn:org.iodp:exp:19urnlargerWorkCitationcampaignurn:org.iodp:exp:19:site:192urnlargerWorkCitationstudyurn:org.iodp:exp:19urnlargerWorkCitationcampaignurn:org.iodp:exp:145:site:883urnlargerWorkCitationstudyurn:org.iodp:exp:145urnlargerWorkCitationcampaignRussiangeoscientificInformation164.4248167.460751.115553.0035