Marine radiocarbon reservoir age variation in Donax obesulus shells from northern Peru: Late Holocene evidence for extended El Niño

Miguel F. Etayo-Cadavid; C. Fred T. Andrus; Kevin B. Jones; Gregory W. L. Hodgins; Daniel H. Sandweiss; Sandiago Uceda-Castillo; Jeffrey Quilter

doi:10.1130/g34065.1

USGS · 70046063

Marine radiocarbon reservoir age variation in Donax obesulus shells from northern Peru: Late Holocene evidence for extended El Niño

Miguel F. Etayo-Cadavid·C. Fred T. Andrus·Kevin B. Jones·Gregory W. L. Hodgins·Daniel H. Sandweiss·Sandiago Uceda-Castillo·Jeffrey Quilter

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Abstract

For at least 6 m.y., El Niño events have posed the greatest environmental risk on the Peruvian coast. A better understanding of El Niño is essential for predicting future risk and growth in this tropical desert. To achieve this we analyzed archaeological and modern pre-bomb shells from the surf clam Donax for the radiocarbon reservoir effect (ΔR) to characterize late Holocene coastal upwelling conditions in northern Peru (8°14′S). Mean ΔR values from these shells suggest that modern upwelling conditions in this region were likely established between A.D. 539 and A.D. 1578. Our radiocarbon data suggest that upwelling conditions ca. A.D. 539 were less intense than those in modern times. The observed coastal water enrichment in 14 C may be consequence of frequent strong El Niño events or extended El Niño–like conditions. These ΔR-inferred marine conditions are in agreement with proposed extended El Niño activity in proxy and archaeological records of ca. A.D. 475–530. Extended El Niño conditions have been linked to political destabilization, societal transformation, and collapse of the Moche civilization in northern Peru. A return to such conditions would have significant impacts on the dense population of this region today and in the near future.

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Geology Article

Source-reported bounding extent: -18.35° to -0.04° latitude; -81.33° to -68.65° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Miguel F. Etayo-Cadavid, C. Fred T. Andrus, Kevin B. Jones, Gregory W. L. Hodgins, Daniel H. Sandweiss, Sandiago Uceda-Castillo, Jeffrey Quilter. 2013-03-18. Marine radiocarbon reservoir age variation in Donax obesulus shells from northern Peru: Late Holocene evidence for extended El Niño. https://doi.org/10.1130/g34065.1

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