Holocene depositional history inferred from single-grain luminescence ages in southern California, North America

Sourav Saha; Seulgi Moon; Nathan D. Brown; Edward J. Rhodes; Katherine M. Scharer; Devin McPhillips; Sally F. McGill; Bryan A. Castillo

doi:10.1029/2021gl092774

USGS · 70223330

Holocene depositional history inferred from single-grain luminescence ages in southern California, North America

Sourav Saha·Seulgi Moon·Nathan D. Brown·Edward J. Rhodes·Katherine M. Scharer·Devin McPhillips·Sally F. McGill·Bryan A. Castillo

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Abstract

Significant sediment flux and deposition in a sedimentary system are influenced by climate changes, tectonics, lithology, and the sedimentary system's internal dynamics. Identifying the timing of depositional periods from stratigraphic records is a first step to critically evaluate the controls of sediment flux and deposition. Here, we show that ages of single-grain K-feldspar luminescence subpopulations may provide information on the timing of previous major depositional periods. We analyzed 754 K-feldspar single-grains from 17 samples from the surface to ∼9 m-depth in a trench located downstream of the Mission Creek catchment. Single-grain luminescence subpopulation ages significantly overlap at least eight times since ∼12.0 ka indicating a common depositional history. These depositional periods correspond reasonably well with the Holocene intervals of wetter than average climate conditions based on hydroclimatic proxies from nearby locations. Our findings imply a first-order climatic control on sediment depositional history in southern California on a millennial timescale.

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Geophysical Research Letters Article

Source-reported bounding extent: 32.62087018318113° to 38.16911413556086° latitude; -122.87109375° to -114.0380859375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Sourav Saha, Seulgi Moon, Nathan D. Brown, Edward J. Rhodes, Katherine M. Scharer, Devin McPhillips, Sally F. McGill, Bryan A. Castillo. 2021-08-09. Holocene depositional history inferred from single-grain luminescence ages in southern California, North America. https://doi.org/10.1029/2021gl092774

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