Features
A Crinoid Conundrum
Uintacrinus was a strange crinoid. Unlike its fellow
crinoid echinoderms, Uintacrinus had arms that could stretch a meter from
its unusually large body. At the same time, past research had suggested
the heavy crinoid was pelagic, moving freely through the ocean to gather
its food. Here, three researchers suggest that the crinoid could not have
lived such a free-floating life. Their evidence comes from slabs containing
extremely well-preserved Uintacrinus fossils. But just as they thought
they might have solved one Uintacrinus mystery, they have found more in
the placements of the well-preserved fossils.
by David. L. Meyer, Clare V. Milsom, and Andrew J.
Webber
The Aggregate Industry:
Present and Future
Megaquarries are the future of the aggregate industry,
says Brian Fowler, a consultant to the aggregate and heavy construction
industries. Here, Lawrence Drew, a geologist with the U.S. Geological Survey,
interviews Fowler, president of North American Reserve Inc. Fowler sees
the demand for aggregate materials increasing — along with resistance from
the public to open new quarries. Megaquarries, huge quarries serving larger
areas than traditional quarries, may become more common, Fowler says. At
the same time, he adds, the costs of producing future aggregate supplies
will increase.
by Lawrence Drew
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