Latest Petrology Stories
University of Michigan scientists have found traces of water from a lunar sample brought back during the Apollo 15 mission.
Neither explosive nor effusive—there’s a new type of volcanic eruption that was recently described in the latest edition of Nature Geoscience.
According to a new study, the Earth's mantle magma melts far hotter and deeper in the Earth's core than previously thought, a discovery that will have lasting implications for geologists.
A new study co-authored by a University of Florida researcher provides the first direct chronological test of sequence stratigraphy, a powerful tool for exploring Earth’s natural resources.
Even though two-thirds of the Earth's solid surface is covered with oceanic crust, scientists still don't entirely understand the process by which it is made.
Hundreds of moon rocks that have been handed out to state governments and foreign countries through the years have gone missing, according to a NASA audit last December. Though some have been recovered, most are still missing.
Although less than two percent of the fossils on earth are preserved in volcanic rock, researchers from the University of Montpellier have identified a new one. They found the skull of a rhino that perished in a volcanic eruption 9.2 million years ago.
Rapid advances in the new and developing field of restoration sedimentology will be needed to protect the world's river deltas from an array of threats.
From Pompeii to Mount St. Helens, we humans have watched in awe, and sometimes horror, the magnificence of volcanic eruptions.
Scientists have identified a trigger for the largest explosive volcanic eruptions on Earth, according to a report published in the journal Scientific Reports.
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...
- Large; stout; burly.