Publication Date:
2024-01-09
Description:
Pelagic clay of the east-central Pacific province is shown to be a mixture of three primary detrital components, reflecting continental source areas in Asia, North America, and Central and South America. Relative contributions from each source area are a function of geography, and this distribution appears to have remained constant over the past five million years, despite changing flux rates. A Q-mode factor analysis of downcore records for Pb, Sr, and Nd isotopes identified three factors that account for 98% of the total variance. These factors represent the radiogenic isotopic signatures of 1) late Cenozoic Asian dust, which dominates in the central North Pacific; 2) North American continental hemipelagic/eolian sources, restricted mainly to the easternmost North Pacific at ~30 °N latitude; and 3) Central and South American sources, restricted to areas east of ~100 °W longitude. South of the Intertropical Convergence Zone (~6 °N), the Asian dust signature diminishes abruptly. We conclude that late Cenozoic Asian dust sources can be isotopically differentiated downcore from both North American and South and Central American sources in the eastcentral Pacific. This approach has a utility for identifying changes in long-term Cenozoic atmospheric circulation patterns.
Keywords:
-; 138-853B; 34-319; 5-32; 67-495; AGE; Calculated; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Event label; EW9709-01PC; EW9709-07PC; Glomar Challenger; Joides Resolution; Latitude of event; Lead-206/Lead-204 ratio; Lead-207/Lead-204 ratio; Lead-207/Lead-206 ratio; Lead-208/Lead-204 ratio; Lead-208/Lead-206 ratio; Leg138; Leg34; Leg5; Leg67; Longitude of event; Mass spectrometer thermal ionization; Multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS); Neodymium-143/Neodymium-144 ratio; North Pacific/PLAIN; North Pacific/TRENCH; North Pacific Ocean; Ocean Drilling Program; ODP; Pacific Ocean; PC; Piston corer; Sample code/label; South Pacific/BASIN; Strontium-87/Strontium-86 ratio; ε-Neodymium
Type:
Dataset
Format:
text/tab-separated-values, 251 data points
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