Latest Petrology Stories
Smithsonian Scientists from the Smithsonian and the University of Rhode Island have found unsuspected linkages between the oxidation state of iron in volcanic rocks and variations in the chemistry of the deep Earth. Not only do the trends run counter to predictions from recent decades of study, they belie a role for carbon circulating in the deep Earth. The team's research was published May 2 in Science Express. Elizabeth Cottrell, lead author and research geologist at the Smithsonian's...
AMSTERDAM, April 29, 2013 /PRNewswire/ -- Submissions welcome until October 10, 2013 Elsevier [http://www.elsevier.com/wps/find/homepage.cws_home ], a world-leading provider of scientific, technical and medical information products and services, and IEDA [http://www.iedadata.org ] (Integrated Earth Data Applications), an NSF-funded data facility in the geosciences at the Lamont-Doherty Earth Observatory of Columbia University, announced today that they are jointly...
TSX-V: GGI Frankfurt: RQM VANCOUVER, March 14, 2013 /PRNewswire/ - Garibaldi Resources Corp. (TSXV: GGI) (the "Company") is pleased to report assay results from its recently completed hole LCT-13-10 at the Locust drill target in Sonora State, Mexico. The hole intersected 23.89 metres of 1.45 g/t gold, including a 2 meter interval that assayed 9.27 g/t gold (see table below). To date 10 holes have been drilled at the project for a total of 1,898.7 meters....
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...
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...
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...
HALIFAX, Nova Scotia, February 19, 2013 /PRNewswire/ -- On behalf of the Board of Directors of Stockport Exploration Inc. (TSX: SPT) (OTC: LMTCF) Wade K. Dawe, Chairman, is pleased to announce the appointment of Zephaniah (Zeph) Mbugua as a Director of Stockport Exploration, effective February 18, 2013. Mr. Mbugua is a resident of Nairobi, Kenya and Chairman of TransCentury, a leading Kenyan investment company traded on the Nairobi Securities Exchange. Mr. Mbugua is...
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...
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 generated by...
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...
Latest Petrology Reference Libraries
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...
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...
