Tag Archives: geologic deposits

Evolution, Civil War History Entwine in Fossil Find

COLLEGE PARK, Md. – A fossil leaf fragment collected decades ago on a Virginia canal bank has been identified by a University of Maryland doctoral student as one of North America’s oldest flowering plants, a 115- to 125-million-year-old species new to science. The fossil find, an ancient relative of today’s bleeding hearts, poses a new puzzle in the study of plant evolution: did Earth’s dominant group of flowering plants evolve along with its distinctive pollen? Or did pollen come later?

The find also unearths a forgotten chapter in Civil War history reminiscent of the film “Twelve Years a Slave,” but with a twist. In 1864, Union Army troops forced a group of freed slaves into involuntary labor, digging a canal along the James River at Dutch Gap, Va. The captive men’s shovels exposed the oldest flowering plant fossil beds in North America, where the new plant species was ultimately found. (more…)

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Tracking Sediments’ Fate in Largest-Ever Dam Removal

Salmon are beginning to swim up the Elwha River for the first time in more than a century. But University of Washington marine geologists are watching what’s beginning to flow downstream — sediments from the largest dam-removal project ever undertaken.

The 108-foot Elwha Dam was built in 1910, and after decades of debate it was finally dismantled last year. Roughly a third of the 210-foot Glines Canyon Dam still stands, holding back a mountain of silt, sand and gravel. (more…)

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