Paleofloods in the Red River Basin

Past Floods
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Paleofloods home
Flooded Red River Basin


Principals of Crossdating

Subfossil fuels from river alluvium

Subfossil fuels
from river alluvium


Timbers from historical buildings

Timbers from
historical buildings

Cores from live trees

Cores from
live trees


Cross Dating


Tree-ring dating uses the outermost ring from living trees as a temporal "anchor" by which other samples, whose outermost ring dates are unknown, are then dated. The pattern of variation within overlapping tree rings allows the samples to be dated absolutely, with annual and sometimes seasonal accuracy. Samples in the Red River oak record are derived from living trees, timbers from 19th century buildings and subfossil logs recovered from river alluvium.

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