API src

Teilprojekt: Hoch-Präzisions Pb (double spike) und Sr-Nd-Hf-Isotopenvariation der oberen Ozeankruste des Leg 206 (Site 1256, östlicher Zentralpazifik)

Description: Das Projekt "Teilprojekt: Hoch-Präzisions Pb (double spike) und Sr-Nd-Hf-Isotopenvariation der oberen Ozeankruste des Leg 206 (Site 1256, östlicher Zentralpazifik)" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), Forschungsbereich 4 Dynamik des Ozeanbodens, Forschungseinheit Magmatische und Hydrothermale Systeme durchgeführt. About 50 percent of the present-day ocean crust and thus -30 percent of the Earth's surface was formed at mid-ocean ridges at fast to superfast spreading rates ( greater than 80 mm/y full rate). IODP Site 1256 in the Cocos Plate (Eastern Central Pacific) represents the most complete in situ section of ocean crust formed at a superfast spreading center drilled thus far. Scientific participants of IODP Expeditions 309 and 312 are currently investigating the recovered material from the deeper, mainly intrusive, part of the hole (below 750 mbsf). Relatively few geochemical data, however, exist thus far for the upper part (drilled during OOP Leg 206) consisting of -250 m of marine sediments and -500 m of lava flows. The upper 750 m represent -50 percent of the total depth drilled at Site 1256. In the course of an ongoing project, our group is investigating the Sr, Nd, Hf and Pb (with the double spike method, DS) isotopic variation in the Exp. 309/312 material, including the low- to high-temperature lava-dike alteration and the dike-gabbro transition zones. Here we propose to examine the down-hole geochemical variation of Leg 206 sediments and lavas, in order to generate a complete and detailed record of the Sr-Nd-Hf-Pb (DS) isotopic and relevant trace element variations of the entire oceanic crust drilled at Site 1256. These data will provide important new insights into 1) magma genesis at superfast spreading ridges (East Pacific Rise); 2) the effects and timing of subsequent alteration including element fluxes in oceanic crust formed at superfast spreading rates (compared to slower rates); 3) the chemical evolution of seawater; 4) element cycles in subduction zones, and 5) the contribution of ocean crust to mantle plume sources. The proposed project is an important extension of our current studies and complements well the research activities within the international Site 1256 IODP scientific community.

Types:

SupportProgram

Origin: /Bund/UBA/UFORDAT

Tags: Kiel ? Hydrothermale Geothermie ? Blech ? Deich ? Geochemie ? Meeressediment ? Meerwasser ? Brunnen ? Meeresboden ? Spurenelement ? Temperatur ? Tiefsee ? Ingenieurgeologie ? Chemikalien ? Daten ? Erdkruste ? Evolution ? Geologie ? Meeresoberfläche ? Paläontologie ? Studie ? Sediment ? Meeresgewässer ? Höhle ? Tiefbohrung ? Bohrung ? Erdoberfläche ? Infrastruktur ? Änderung ? Pazifischer Ozean ? Entwicklungszone [Biosphärenreservat] ?

Region: Schleswig-Holstein

Bounding box: 9.75° .. 9.75° x 54.2° .. 54.2°

License: cc-by-nc-nd/4.0

Language: Deutsch

Organisations

Time ranges: 2008-01-01 - 2011-12-31

Alternatives

Resources

Status

Quality score

Accessed 1 times.