Project Details
Projekt
231Pa/230Th profiles from highly accumulating Atlantic sediment cores - a proxy for deep water circulation over the past 30,000 years
Applicant
Professor Dr. Augusto Mangini
Subject Area
Palaeontology
Term
from 2007 to 2010
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 48922712
In the Atlantic Ocean sedimentary 231Pa/230Th below the production ratio of 0.093 are believed to mirror the advective export of 231Pa to the Southern Ocean due to the meridional overturning circulation (MOC). Times of shifted 231Pa/230Th related with prominent events of cooling and warming support the conclusion that variations in the MOC may incite climate changes. However, the impact of boundary scavenging on the 231Pa/230Th in the glacial Atlantic is a great matter of discussion.The goal of this project is to better understand the behaviour of 231Pa/230Th in Holocene and Glacial sediments both, in the open Ocean and in the upwelling areas in the East Atlantic. The ability to quantify possible boundary scavenging effects will substantially improve our understanding and the interpretation of sedimentary 231Pa/230Th-records as a proxy for the strength of MOC. To approach this goal sedimentary 231Pa/230Th profiles from two high-productivity cores off the coast of Namibia and one off West-Africa are compared with those from the North-, West-, and South- Atlantic Ocean. For the first time 231Pa/230Th from high productivity sediment cores from the African margin at adequate accuracy are being measured by AMS and ICP-MS. The analysis is focused on the last 30 kyr. The high accumulation rates of the selected sediment cores allow a very good time resolution. Therefore, it will be possible to examine the response of the sedimentary 231Pa/230Th to several short-term climate events (e.g. Heinrich Events).
DFG Programme
Infrastructure Priority Programmes
International Connection
Switzerland
Participating Person
Dr. Marcus Christl
