Latest Clastic rock Stories
In this issue, Gregory Retallack and Joshua Roering of the University of Oregon enter the long-standing debate as to whether rock platforms along coasts and rivers are the product of physical erosion or chemical weathering above the water table.
Pebbles that become part of clastic rocks in places like Arizona's Lower Antelope Canyon don't move with the wind but against it, a geosciences professor said. Rather than being pushed into formations, the pebbles, or clasts, have the loose sand around them removed by the wind, Andrew Leier of the University of Calgary said in the journal Geology. The sand removal causes scour-pits to form on the wind side of larger clasts, and the pebbles eventually fall toward the wind into the scours, he...
At first, figuring out how pebble-sized rocks organize themselves in evenly-spaced patterns in sand seemed simple and even intuitive. But once Andrew Leier, an assistant geoscience professor at the U of C, started observing, he discovered that the most commonly held notions did not apply.
TORONTO, ONTARIO--(Marketwire - Sept. 24, 2008) - THIS NEWS RELEASE IS NOT FOR DISTRIBUTION TO U.S.
In geology, a conglomerate is a rock consisting of other stones that have been cemented together. Conglomerates are sedimentary rocks consisting of subangular clasts and are thus differentiated from breccias, which consist of angular clasts. Both conglomerates and breccias are characterized by clasts larger than sand (>2 mm). There are two varieties of conglomerate, defined by texture: paraconglomerates and orthoconglomerates. Paraconglomerates are one of two varieties of conglomerate...
- Small missiles, especially grape, canister, fragments of iron, and the like, when fired, as upon an enemy at close quarters.
- To fire mitraille at.