The Keys To Unlocking Transitions in Water
When examining waters transition from fresh to salt as well as from salt
to fresh one quickly finds the importance of estuaries. In terms of geology,
present-day estuaries are young and ephemeral coastal features. Today's
estuaries began to take their current form during the last interglacial period,
when sea level rose about 120 m (Braun 36). However, the relatively high sea
levels and extensive estuaries found today have been characteristic of only
about 10 to 20 percent of the last million years. When sea level was lower,
during glaciation periods, estuaries were much smaller than they are at present
and were located on what is now the continental slope. Unless sea level rises,
estuaries tend to fill with sediments and become much smaller. The sediments
come from riverborne terrestrial materials from the eroding continents and from
sand transported upstream by the tides from the continental shelf (Braun 55).
It is in estuaries that......
Join Now or Login to view the rest of this paper.
Approximate Word Count: 398
Approximate Pages: 2 (260 words per double-spaced page) |