Highland Breccia
On Earth, the surface is eroded by the action of water and wind. The most important process for altering the surface of the moon, however, is that of impacting upon and breaking up the surface. This lunar sample is a rock type named .
Breccia
A rock composed of fragments of earlier rocks bonded together.
Brown Dwarf ...
Breccia: Rock consisting of angular, coarse fragments embedded in a fine-grained matrix.
BRECCIA - Clastic sedimentary rock composed of angular clasts in a consolidated matrix.
BRECCIA
Breccia is a type of rock that is composed of rough, angular pieces of broken-up, older rocks. Impact craters produce breccia.
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Breccias, which are fragments of different rocks compacted and welded together by meteor impacts, are found in the Maria and the Highlands, but are more common in the latter.
Breccia-type rocks are common on the moon, but they're believed to be rare on Mars.
"The bottom line is we are seeing a rock type here that is different than anything we've ever seen before," Squyres said.
These events caused a variety of effects, ranging from simple compaction to brecciation, veining, localized melting, and formation of high-pressure minerals.
A layer of shattered or "brecciated" rock under the floor of the crater. This layer is called a "breccia lens".
Shatter cones, which are chevron-shaped impressions in rocks. Such cones are formed most easily in fine-grained rocks.
At their various stops during the first two days, they had found white breccias with black inclusions and also black breccias with white inclusions. And, at North Ray, the pattern was even more striking.
The highlands have been so battered by ancient impacts that most of the surface has been reduced to a rubble that geologists call breccia.
In the highlands the majority of the rocks are breccias—conglomerates formed from basaltic rock and often studded with small, green, glassy spheres.
Some volcanic features can resemble impact craters, and brecciated rocks are associated with other geological formations besides impact craters.
We now know that the highlands are made of rocks called anorthosite and polymict breccia.
4 kg (27 lb) and was subsequently identified as an H6 monomict breccia meteorite.[17] The video record suggests that the Peekskill meteorite probably had several companions over a wide area especially in the harsh terrain in the vicinity of Peekskill.
A conglomerate is a Rock consisting of individual stones that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts....
Left, some mare basalt. Notice how porous it is, very much like volcanic basalt on the Earth. Center, anorthosite, the rock from the highlands. Right, breccia, formed by impacts that cement together rocks.
Other important lunar sample types include glasses, breccias (complex assemblages of rock fragments cemented together by heat or pressure, or both), ...
 See also: Earth, Rock, Moon, Meteor, Solar
  
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