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Seas Of Molten Rock Created By Lunar Impacts
2013-03-12 04:54:36

April Flowers for redOrbit.com - Your Universe Online An ocean of molten rock covered the entire lunar surface during the early part of the Moon's history. Over millions of years, that magma ocean cooled, differentiating to form the crust and mantle. According to new analysis of NASA's Lunar Orbiter Laser Altimeter (LOLA) data, led by Brown University planetary scientists, this wasn't the last time the Moon's surface melted on such a massive scale. Graduate student William Vaughan led...

2013-03-11 23:01:03

The Sedimentary Geology Laboratory (LAGESED) of UFRJ, coordinated by Prof. Dr. Leonardo Borghi, acquired the updated versions of Petroledge and RockViewer systems for petrographic knowledge management of carbonate and siliciclastic rocks. Rio de Janeiro, RJ (PRWEB) March 11, 2013 The Sedimentary Geology Laboratory (LAGESED) of UFRJ, coordinated by Prof. Dr. Leonardo Borghi, acquired the updated versions of Petroledge and RockViewer systems for petrographic knowledge management of carbonate...

Mercury May Have Hosted A Magma Ocean In Its Past
2013-02-21 13:29:25

Lee Rannals for redOrbit.com - Your Universe Online Scientists analyzing data from NASA's MESSENGER spacecraft say that Mercury once harbored an ancient magma ocean. An MIT team of scientists say that Mercury may have had a large ocean of magma very early in its history, shortly after its formation about 4.5 billion years ago. A group of scientists analyzed X-ray fluorescence data from MESSENGER collected back in 2011. They were able to identify two distinct compositions of rocks on...

Traces Of Water Found In Apollo 15 Lunar Sample
2013-02-18 14:39:05

Lee Rannals for redOrbit.com — Your Universe Online University of Michigan scientists have found traces of water from a lunar sample brought back during the Apollo 15 mission. The lunar sample, known as "Genesis Rock," was thought to be a piece of the moon's primordial crust, and researchers writing in Nature Geoscience are now reporting they have found traces of water in the rock. The traces of water were detected within the crystalline structure of mineral samples taken from...

New Type Of Volcanic Eruption Described By Scientists
2013-01-21 10:41:33

Brett Smith for redOrbit.com - Your Universe Online 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 the U.K. and New Zealand scientists who authored the description, volcanic pumice produced by the Macauley volcano in the southwest Pacific is the result of a previously unarticulated type of eruption. “By documenting the shape and density of bubbles in pumices...

Earth’s Magma Mantle Melts Hotter Than Previously Thought
2013-01-10 10:10:41

April Flowers for redOrbit.com - Your Universe Online According to a new study by researchers at Rice University, 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 our understanding of the planet's geophysical and geochemical properties. The research team, led by Rajdeep Dasgupta, put small amounts of peridotite under large pressures in a laboratory to determine that rock can and does...

New Test Helps With Understanding Earth’s History And Resources
2012-12-06 10:18:32

University of Florida 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. The model allows geologists to better understand how sedimentary rocks are related to one another in time and space and predict what types of rocks are located in different areas. The information may help scientists more reliably interpret various aspects of Earth´s...


Latest Petrology Reference Libraries

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...

28_0d277ca2b0d8b8cd79fb9cfa322f77e1
2005-05-26 11:01:52

Diorite is a grey to dark grey intermediate intrusive igneous rock composed principally of plagioclase feldspar (typically andesine), hornblende, and/or pyroxene. Varieties deficient in hornblende and other dark minerals are called leucodiorite. It is often described as "salt and pepper" when composed largely of light-colored minerals randomly interspersed with dark minerals. When olivine and more iron-rich augite are present, the rock grades into ferrodiorite, which is transitional to...

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Word of the Day
snash
  • To talk saucily.
  • Insolent, opprobrious language; impertinent abuse.
This word is Scots in origin and probably imitative.