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USGS · 70156823

Sub-decadal turbidite frequency during the early Holocene: Eel Fan, offshore northern California

Charles K. Paull·Mary L. McGann·Esther J. Sumner·Philip M Barnes·Eve M. Lundsten·Krystle Anderson·Roberto Gwiazda·Brian D. Edwards·David W Caress
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Abstract

Remotely operated and autonomous underwater vehicle technologies were used to image and sample exceptional deep sea outcrops where an ∼100-m-thick section of turbidite beds is exposed on the headwalls of two giant submarine scours on Eel submarine fan, offshore northern California (USA). These outcrops provide a rare opportunity to connect young deep-sea turbidites with their feeder system. 14 C measurements reveal that from 12.8 ka to 7.9 ka, one turbidite was being emplaced on average every 7 yr. This emplacement rate is two to three orders of magnitude higher than observed for turbidites elsewhere along the Pacific margin of North America. The turbidites contain abundant wood and shallow-dwelling foraminifera, demonstrating an efficient connection between the Eel River source and the Eel Fan sink. Turbidite recurrence intervals diminish fivefold to ∼36 yr from 7.9 ka onward, reflecting sea-level rise and re-routing of Eel River sediments.

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Charles K. Paull, Mary L. McGann, Esther J. Sumner, Philip M Barnes, Eve M. Lundsten, Krystle Anderson, Roberto Gwiazda, Brian D. Edwards, David W Caress. 2014. Sub-decadal turbidite frequency during the early Holocene: Eel Fan, offshore northern California. https://doi.org/10.1130/g35768.1

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