Holocene evolution in weathering and erosion patterns in the Pearl River delta
Clift, Peter D.
Hannigan, Robyn E.
Blusztajn, Jerzy S.
Fuller, Dorian Q.
MetadataShow full item record
KeywordPhysical erosion; Chemical weathering; Human settlement; Proxies; Landscape; Pearl river basin; Archaeology
Sediments in the Pearl River delta have the potential to record the weathering response of this river basin to climate change since 9.5 ka, most notably weakening of the Asian monsoon since the Early Holocene (∼8 ka). Cores from the Pearl River delta show a clear temporal evolution of weathering intensity, as measured by K/Al, K/Rb, and clay mineralogy, that shows deposition of less weathered sediment at a time of weakening monsoon rainfall in the Early-Mid Holocene (6.0–2.5 ka). This may reflect an immediate response to a less humid climate, or more likely reduced reworking of older deposits from river terraces as the monsoon weakened. Human settlement of the Pearl River basin may have had a major impact on landscape and erosion as a result of the establishment of widespread agriculture. After around 2.5 ka weathering intensity sharply increased, despite limited change in the monsoon, but at a time when anthropogenic pollutants (e.g., Cu, Zn, and Pb) increased and when the flora of the basin changed. 87Sr/86Sr covaries with these other proxies but is also partly influenced by the presence of carbonate. The sediments in the modern Pearl River are even more weathered than the youngest material from the delta cores. We infer that the spread of farming into the Pearl River basin around 2.7 ka was followed by a widespread reworking of old, weathered soils after 2.5 ka, and large-scale disruption of the river system that was advanced by 2.0 ka.
Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013); 2349–2368, doi:10.1002/ggge.20166.
Suggested CitationGeochemistry, Geophysics, Geosystems 14 (2013); 2349–2368
Showing items related by title, author, creator and subject.
Fiege, Katherina; Miller, Christian A.; Robinson, Laura F.; Figueroa, Ricardo; Peucker-Ehrenbrink, Bernhard (2009-08-26)Analyses of Chilean river waters indicate that the average yield of unradiogenic Sr (~ 517 mol Sr km− 2 yr− 1, 87Sr/86Sr ~ 0.7057) from western South America (1,220,853 km2) into the southeastern Pacific Ocean is ~ 2–4 ...
Sulfur isotopes in rivers : insights into global weathering budgets, pyrite oxidation, and the modern sulfur cycle Burke, Andrea; Present, Theodore M.; Paris, Guillaume; Rae, Emily C. M.; Sandilands, Brodie H.; Gaillardet, Jerome; Peucker-Ehrenbrink, Bernhard; Fischer, Woodward W.; McClelland, James W.; Spencer, Robert G. M.; Voss, Britta M.; Adkins, Jess F. (2018-05)The biogeochemical sulfur cycle is intimately linked to the cycles of carbon, iron, and oxygen, and plays an important role in global climate via weathering reactions and aerosols. However, many aspects of the modern budget ...
A land-to-ocean perspective on the magnitude, source and implication of DIC flux from major Arctic rivers to the Arctic Ocean Tank, Suzanne E.; Raymond, Peter A.; Striegl, Robert G.; McClelland, James W.; Holmes, Robert M.; Fiske, Gregory J.; Peterson, Bruce J. (American Geophysical Union, 2012-12-14)A series of seasonally distributed measurements from the six largest Arctic rivers (the Ob', Yenisey, Lena, Kolyma, Yukon and Mackenzie) was used to examine the magnitude and significance of Arctic riverine DIC flux to ...