Geochemistry of ODP Site 202-1233 and river sediments ...

• Main Authors: Muratli, Jesse M, Chase, Zanna, McManus, James, Mix, Alan C
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2010
• Subjects: Ocean Drilling Program ODP; Ice Sheet
• Online Access: https://dx.doi.org/10.1594/pangaea.816355; https://doi.pangaea.de/10.1594/PANGAEA.816355

Bulk sediment chemistry from three Chilean continental margin Ocean Drilling Program sites constrains regional continental erosion over the past 30,000 years. Sediments from thirteen rivers that drain the (mostly igneous) Andes and the (mostly metamorphic) Coast Range, along with existing rock chemistry datasets, define terrestrial provenance for the continental margin sediments. Andean river sediments have high Mg/Al relative to Coast-Range river sediments. Near 36°S, marine sediments have high-Mg/Al (i.e. more Andean) sources during the last glacial period, and lower-Mg/Al (less Andean) sources during the Holocene. Near 41°S a Ti-rich source, likely from coast-range igneous intrusions, is prevalent during Holocene time, whereas high-Mg/Al Andean sources are more prevalent during the last glacial period. We infer that there is a dominant ice-sheet control of sediment sources. At 36°S, Andean-sourced sediment decreased as Andean mountain glaciers retreated after ~17.6 ka, coincident with local oceanic ... : Supplement to: Muratli, Jesse M; Chase, Zanna; McManus, James; Mix, Alan C (2010): Ice-sheet control of continental erosion in central and southern Chile (36°-41°S) over the last 30,000 years. Quaternary Science Reviews, 29(23-24), 3230-3239 ...