Seven radiocarbon samples of tidal marsh plant remains were used to date the penultimate tsunami at Discovery Bay to 1320-1390 CE, or approximately 600 years old. Samples were selected that either pre-dated or post-dated (or were roughly the same age as) the tsunami event.  Image below shows a sampled outcrop, as well as a schematic of Bed 2 showing sample positions for samples 1-7 relative to the tsunami deposit.  The resulting modeled age range next to the schematic shows the 2 sigma probability distributions for each age range in the model, and the resulting age.

Dried radiocarbon sample 7 of the intertidal marsh plant Triglochin maritima (below left), and a modern specimen of Triglochin maritima living at Discovery Bay (below right). 

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