Publication Date:
2024-01-09
Description:
Ocean circulation may have undergone reductions and reinvigorations in the past closely tied to regional climate changes. Measurements of 231Pa/230Th ratios in a sediment core from the Bermuda Rise have been interpreted as evidence that the Atlantic Meridional Overturning Circulation (AMOC) was weakened or completely eliminated during a period of catastrophic iceberg discharges (Heinrich-Event 1, H1). Here we present new data from the Bermuda Rise that show further 231Pa/230Th peaks during Heinrich-2 (H2) and Heinrich-3 (H3). Additionally, a tight correlation between diatom abundances (biogenic silica) and 231Pa/230Th is discovered in this core. Our results redirect the interpretation of 231Pa/230Th from the Bermuda Rise as a proxy for ocean circulation towards a proxy that reacts highly sensitive to changes of particle composition and water mass properties.
Keywords:
172-1063B; 172-1063D; AGE; Blake-Bahama Outer Ridge, North Atlantic Ocean; Calculated; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Event label; Inductively coupled plasma - mass spectrometry (ICP-MS); Joides Resolution; Leg172; Ocean Drilling Program; ODP; Protactinium-231; Protactinium-231, error, relative; Protactinium-231/Thorium-230 excess, decay-corrected; Protactinium-231/Thorium-230 excess, decay-corrected, error, relative; Sample code/label; South Atlantic Ocean; Thorium-230; Thorium-230, error, relative; Thorium-232; Thorium-232, error, relative; Uranium-234; Uranium-234, error, relative; Uranium-238; Uranium-238, error, relative
Type:
Dataset
Format:
text/tab-separated-values, 748 data points
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