May 17, 2013. Compared with the western part of North America — a mountainous, volcanic and seismic — geologically quiet east coast received the name "passive continental margin."
However, new geological models suggest that the boiling bowels of the earth deform and distort this and many other so-called stable area.
Three million years ago, Earth was a few degrees warmer than today, and about the same temperature awaits us in 2100. Geologists want to know how the coastlines of continents looked at
Maybe something is still pushing up land? Geologist
See also: In the Chesapeake Bay is sinking island
Group Mr. Rowley found subtle movement mantle beneath the eastern part of North America, including in the model layer of relatively liquid rock directly under the hard shell of the Earth — the asthenosphere. A model that does not account for the asthenosphere, showed that Orangeburg must sink. Clearly, however, it rises, and uneven — here and there. According to Mr. Rowley, a similar effect he modeled for Africa and the Colorado Plateau in the south-western United States. "The whole earth is going on a dynamic mantle," — he said.
Dynamic gown might skew the passive margins so that the researchers correctly read the geologic record of changes in sea level during the Pliocene and found them more sharp than they were in reality. Apparently, the authors of climate models have to be revised forecast of sea level rise in a warming world. (Dynamic topography, we note once again, does not change the level of the sea, but moves the mark by which to judge the climate of the Earth in the past.)
The findings suggest that the Atlantic coast can no longer be passive margin. "She's a passive-aggressive — says geologist
A more accurate assessment of sea level during the Pliocene help geologists understand how much the ice sheets melted at that time, says Mr. Dowsett, and thus to look into our own future.
"But my work on this will not be easy — smiling specialist on the reconstruction of coastlines Pliocene based on microfossils. — On the contrary, become more difficult. "
The study is published in the journal