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Breaking research news from a team of scientists led by Carnegie's Ho-kwang "Dave" Mao reveals that the composition of the Earth's lower mantle may be significantly different than previously thought.
Volcanologists from the University of Liverpool have discovered how lava dome volcanoes erupt. This could help develop methods on predicting how volcanoes will act.
While magma levels are rising at Mount St. Helens in Washington, there is now evidence that the active stratovolcano will not be erupting any time soon.
Kīlauea volcano, on the Big Island of Hawai'i, typically has effusive eruptions, wherein magma flows to create ropy pāhoehoe lava, for example. However, Kīlauea less frequently erupts more violently, showering scoria and blocks over much of the surface of the island.
VANCOUVER, April 29, 2014 /PRNewswire/ - Sierra Metals Inc.
University of Calgary-led research is first of its kind, uncovering the origin of oilsands sediment
New research by UC Davis and Oregon State University may soon lead to new forecasts into how soon volcanoes are ready to erupt. The team found that in order for an eruption to occur, molten rock under the volcano must be sufficiently mobile.
The exceptional preservation and diversity of dinosaur, bird and early mammal fossils present in the fossil beds of northern China are famous. How these creatures died, and why hundreds of creatures from different habitats were buried together on ancient lake floors, has yet to be understood.
Folklore says that mysterious basalt pillars found in Iceland were created by a pair of angry trolls who hurled rocks at one another. However, a new study says that these pillars actually formed around vertical columns of steam and hot water venting through lava.
A team of researchers have discovered a large magma chamber deep under the most active volcano in the world. It is the first time research has been able to confirm such a discovery in Kilauea's depths.
Chaitén is a volcanic caldera that is located in southern Chile that reaches an elevation of 3,681 feet. It is thought that this volcano once held a rhyolite obsidian lava dome that reached 3,156 in height, but this was destroyed after its most recent eruption in 2008. In the past, this volcano has released grey obsidian, which was used by pre-Columbian cultures to make many objects, some of which have been found 250 miles away from the volcano. Chaitén experienced the beginning of a new...
Biotite is a common phyllosilicate mineral that contains potassium, magnesium, iron and aluminium. It is sometimes called "iron mica" and is found in granitic rocks, gneisses, and schists. Like other mica minerals, biotite has a highly perfect basal cleavage, its flexible sheets easily flaking off. It has a hardness of 2.5 - 3, a specific gravity of 2.7 - 3.1, is colored greenish to brown or black, and can be transparent to opaque. Biotite is occasionally found in large sheets, especially in...
Chert is a fine-grained silica-rich cryptocrystalline sedimentary rock that may contain small fossils. It varies greatly in color from white to black, but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements present in the rock, and both red and green are most often related to traces of iron (in its oxidized and reduced forms respectively). It outcrops as nodules in limestone, chalk, and dolostone formations as a...
Chromite, iron magnesium chromium oxide: (Fe,Mg)Cr2O4, is an oxide mineral belonging to the spinel group. Magnesium is always present in variable amounts, also aluminium and iron substitute for chromium. Chromite is found in peridotite and other layered ultramafic intrusive rocks and also found in metamorphic rocks such as serpentinites. Ore deposites of chromite form as early magmatic differentiates. It is commonly associated with olivine, magnetite, serpentine, and corundum. Chromite is...
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...
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