Quantcast

Latest Petrology Stories

Trigger For Explosive Volcanic Eruptions Identified
2012-10-13 09:27:11

Lee Rannals for redOrbit.com — Your Universe Online Scientists have identified a trigger for the largest explosive volcanic eruptions on Earth, according to a report published in the journal Scientific Reports. University of Southampton researchers investigated crystal cumulate nodules and their trapped magma to see what caused eruptions at the Las Cañadas volcanic caldera on Tenerife, in the Canary Islands. This volcano has generated at least eight major...

Pre-eruption Activity In Conduits Affect Volcanic Ejections
2012-07-24 13:53:55

Brett Smith for redOrbit.com - Your Universe Online In addition to being fairly unpredictable, volcanoes can eject a wide range of material, from mile-high plums of black ash to a deadly hail of fist-sized pumice. These ejections travel extremely fast and can reach internal temperatures between 750 to 1,500 degrees Fahrenheit. The prevailing theory has been that the difference in particle size determined when bubbling magma deep below the volcano converts into a rising stream of gas and...

2012-06-19 00:15:58

New Geology articles posted online ahead of print June 15 Orange-like rocks in Utah with iron-oxide rinds and fossilized bacteria inside that are believed to have eaten the interior rock material, plus noted similarities to "bacterial meal" ingredients and rock types on Mars; fine-tuning the prediction of volcanic hazards and warning systems for both high population zones and at Tristan da Cunha, home to the most remote population on Earth; news from SAFOD; and discovery in Germany of the...

Former NASA Investigator On The Hunt For Missing Moon Rocks
2012-05-14 07:35:10

In December 2011, NASA Inspector General Paul Martin issued a report stating that more than 500 pieces of moon rocks, meteorites, and other debris from space were either stolen or have been missing since 1970. Now, a Houston lawyer is on a mission to identify and possibly recover many of these rare treasures. The moon rocks he is on the hunt for were brought back to Earth and then subsequently lost after being loaned to scientists, museums and agencies throughout the world. The samples...


Latest Petrology Reference Libraries

Chaitén
2014-08-28 10:38:21

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...

28_e9750264d5476c85f9be09d17bc6fd51
2005-05-26 12:03:39

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...

28_56635877b282726a86b25cf3e98722c2
2005-05-26 11:30:45

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...

28_42121cee4c09c0898f52263bea588d54
2005-05-26 11:26:59

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...

28_b760796d3dace508242e89fc53d49081
2005-05-26 11:13:08

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...

More Articles (18 articles) »
Word of the Day
negawatt
  • A unit of saved energy.
Coined by Amory Lovins, chairman of the Rocky Mountain Institute as a contraction of negative watt on the model of similar compounds like megawatt.