
	Where results make sense

Topic: Metasomatism

Related Topics

Metamorphic rock

Petroleum geology

Hydrology

Extinction event

Carnation Revolution

	MYRMEKITE 36 OF 50; How K-metasomatism is accomplished
		For example, the metasomatic reactions could occur where pressure varies from place to place or where the system is opened so that more K can be added in solutions than is in the original system and/or more Ca and Na are subtracted than are in the original system.
		Because of the relative speed of the metasomatic reactions in the experimental studies, Orville suggested that great volumes of moving fluids are not necessary to accomplish the metasomatism.
		During metasomatism K and Si have replaced those parts of the brecciated syenite which are strongly crushed, converting them to granite syenite which are strongly crushed, converting them to granite, but islands of uncrushed syenite were impervious to replacing vapors and solutions and remain scattered with sharp contacts in the metasomatic granite.
	www.csun.edu /~vcgeo005/Orville.htm (5787 words)

	METASOMATISM (Gr. /ser... - Online Information article about METASOMATISM (Gr. /ser...
		As a result of metasomatism rocks usually become more crystalline, especially those which have been in large part built up of fossil organic remains; this is a consequence of the new substances having been deposited by purely inorganic processes from solution in water.
		In metasomatism, on the other- hand, chemical alteration is supposed by most geologists to be an essential feature; new minerals appear, but the original structures are sometimes retained.
		The facility with which a rock undergoes metasomatism depends partly on its nature, and partly on the circumstances in which it is placed.
	encyclopedia.jrank.org /MEC_MIC/METASOMATISM_Gr_sera_change_o_w.html (2045 words)

	Metasomatism - Encyclopedia, History, Geography and Biography
		Metasomatism is more complicated in the Earth's mantle, because the composition of peridotite at high temperatures can be changed by infiltration of carbonate and silicate melts and by carbon-dioxide-rich and water-rich fluids, as discussed by Luth (2003).
		Metasomatism is thought to be particularly important in changing the composition of mantle peridotite below island arcs as water is driven out of ocean lithosphere during subduction.
		Modal metasomatism may result in formation of amphibole and phlogopite, and the presence of these minerals in peridotite xenoliths has been considered strong evidence of metasomatic processes in the mantle.
	www.arikah.com /encyclopedia/Metasomatism (930 words)

	Body (Site not responding. Last check: )
		Hence, disclosure of the physicochemical conditions causing the metasomatic wall rock alterations is a clue to understanding the ore deposition environments with respect of temperature, pressure, chemical composition of solutions, and duration of rock-fluid interaction, thus obtaining a basis for revealing causes and mechanisms of ore deposition.
		Since metasomatism and ore deposition are closely related, we conducted experimental study of deposition of the rare metal ore deposition simultaneous to the processes of acidic and alkaline metasomatism in granites.
		The latter is similar in its composition to the most altered rear zones of the acidic metasomatic columns with major chemical elements removed, except Si, Al and K. Hence, the phase composition of the fields on the chart resembles the mineral composition of the rear zones inherent in corresponding natural metasomatic assemblages.
	www.iem.ac.ru /staff/zarp1.html (5715 words)

	Scientific Directions and Some Results
		The large forces of Laboratory were involved in the development of metasomatism problems, in the majority of cases combined with forming of different ores.
		Such zoning depending on temperature were investigated at deeper metasomatism levels in propilite formations of Au-deposits of Far East, bottom part of the Amur river, the Kurama region of Uzbekistan (Rusinov,1989).
		The criterions of distinction of metasomatic and magmatic rock types were worked out on the basis of the paragenetic analysis and the composition variation of the rock-forming minerals.
	www.igem.ru /lfca/eng/direct.htm (2196 words)

	UTas ePrints - Carbonatite metasomatism in the southeastern Australian lithosphere
		Metasomatism occurred when ascending dolomitic carbonatites crossed the reaction enstatite + dolomite = forsterite + diopside + CO2 at similar to 1.5-2.0 GPa, resulting in partial to complete replacement of primary orthopyroxene by sodic clinopyroxene, together with crystallization of apatite, amphibole and phlogopite, and release of CO2-rich fluid.
		In the sample suite examined, the minimum amount of carbonatite melt may be estimated on the assumption that metasomatism occurred in a closed system, and that the precursor lithology was clinopyroxene-poor harzburgite.
		However, metasomatism probably also involved an open system component, during which by partitioning relationships with the reacting carbonatite, resulting in loss from the metasomatized volume of a fugitive, siliceous, aluminous, alkali- and LILE-enriched silicate melt.
	eprints.utas.edu.au /326 (234 words)

	metasomatism - Search Results - MSN Encarta
		Metasomatism and metasomatic rocks 1 Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: Web version 01.02.07 V.A. Zharikov 2, N.N. metasomatism: definition, usage and pronunciation - YourDictionary.com...
		Metasomatism definition, words related to metasomatism, proper usage and pronunciation of the word...
		Metasomatism - The chemical alteration of rocks or minerals by interaction with liquids.
	encarta.msn.com /metasomatism.html (165 words)

	Untitled Document
		Metasomatic rocks are formed when an original rock is transgressed by mineralized solutions (liquid and/or vapor) that react in passing to produce material of new composition.
		Metasomatic rocks are widespread in the Earth's crust and upper mantle, and they frequently are exotic in mineralogy and texture.
		It is reasonably established that the host rock (called gabbroic troctolite) originated by sedimentation of plagioclase and olivine crystals on the floor of the original magma body as it cooled and solidified, and that the metasomatism was imposed as the pore liquid between the accumulated crystals gradually solidified.
	www.carnegieinstitution.org:16080 /YearBook_99_00/scientists/Yoder_Irvine/Irvine_Yoder.html (533 words)

	Metasomatism Rocks & Minerals - Find Articles (Site not responding. Last check: )
		The susceptibility of a rock to metasomatism depends partly on its mineralogical and structural characteristics and partly on the characteristics of the fluid (i.e., temperature, pressure, pH, oxygen-reduction potential, and water/rock ratio).
		An excellent example of metasomatism is the formation of a skarn (Rakovan 2003), wherein Si from an intruded magma is added to a limestone, usually through the activity of hydrothermal fluids, and combines with Ca to form the Ca-silicate minerals characteristic of skarns.
		A classic example with an interesting history is the metasomatic replacement of limestones in the Magdalena mining district in Socorro County, New Mexico (Loughlin and Koschmann 1942).
	www.findarticles.com /p/articles/mi_m0GDX/is_1_80/ai_n8694220 (842 words)

	Amazon.com: metasomatism (Site not responding. Last check: )
		Investigations of the alkali metasomatism in feldspars (Polska Akademia Nauk.
		Metasomatism and mineral facies in relation to structure in northeastern Albany County, Wyoming by Frank W Osterwald (Unknown Binding - 1947)
		Recognition and geologic implications of potassium metasomatism in upper-plate volcanic rocks at the detachment fault at the Harcuvar Mountains, Yavapai...
	www.amazon.com /s?ie=UTF8&keywords=metasomatism&index=blended&page=1 (474 words)

	Granite Countertops and Vanity Tops at All Granite And Marble Corp
		Metasomatism is the drastic change in the bulk chemical composition of a rock that often occurs during the process of metamorphism.
		The formation of important ore minerals may occur by the process of metasomatism at or near the contact zone.
		Regional metamorphism is the name given to changes in great masses of rock over a wide area, often within orogenic belts.
	www.marble.com /countertops/encyclopedia/27/metamorphic,rock.html (938 words)

	Metamorphism
		is the localized metamorphism occurring immediately adjacent to an igneous pluton (large mass of magma, roughly equivalent to a magma chamber) caused by increasing temperature and/or possible metasomatism (diffusion of elements and fluids between the magma and the rocks surrounding the igneous pluton resulting in a change of composition).
		The Muzo and Chivor emeralds occur in veins of calcite and albite that occur in organic-rich shales and limestones.
		With the exception of minerals such as calcite, quartz, gypsum, and celestite, precipitated by aqueous solutions in cavities or caves in sediments or sedimentary rocks near the Earth's surface, sedimentary minerals rarely are as breathtakingly beautiful as igneous and metamorphic minerals.
	www.utexas.edu /tmm/npl/mineralogy/Mineral_Genesis/Metamorphism.htm (621 words)

	The Cornubian Batholith
		The development of the megacrysts has been suggested to have taken place when the magma had cooled sufficiently to exsolve its water, and it is usual to find a highly megacrystic facies near the walls and roofs of the plutons.
		Metasomatism is the alteration of country rocks and the intrusion by circulating hydrothermal fluids.
		This is the metasomatic replacement of feldspars and micas by the mineral tourmaline.
	www.graniteinstallation.com /cornbath.htm (1929 words)

	MYRMEKITE 4 of 50
		The metasomatism is not large scale but local, using Ca and Na released during metamorphism of minerals available in a volume smaller than that represented by a thin section.
		The metasomatism produces a corona of myrmekite around the K-feldspar.
		K-feldspar megacrysts lacking myrmekite coronas can be found in undeformed granitic gneisses outside the contact aureole.
	www.csun.edu /~vcgeo005/revised4.htm (1149 words)

	[No title]
		Metasomatic rocks in amphibolite consist of the mineral assemblage hbl-ap, with an average modal abundance of 99% for hbl.
		Group II metasomatic rocks occur at discordant contacts and are interpreted to have developed from the infiltration of metasomatizing fluids through a shear.
		The data indicates that metasomatic rocks have a composition that is intermediate between the compositions of amphibolite and metaultramafic rocks.
	nwdata.geol.pdx.edu /Thesis/Abstract.php?Th_ID=94 (581 words)

	Metasomatism (Site not responding. Last check: )
		Metasomatism is a geologic process where metamorphism causes an alteration in a mineral or rock mass that involves a chemical change of the substance with the addition of material, as when chrysolite (olivine) is converted to serpentine basically by the addition of water.
		This is contrasted with ordinary metamorphism which varies from simple recrystallization (example: sandstone to quartzite), which is a physical change; to recrystallization with local migration of chemicals resulting in chemical change of the minerals with no external addition of materials.
		The added material may come from magmatic fluids, moving connate fluids, or from convective circulating groundwater or seawater.
	www.xasa.com /wiki/en/wikipedia/m/me/metasomatism.html (135 words)

	8th INTERNATIONAL KIMBERLITE CONFERENCE (8IKC)
		The oldest metasomatic event (Type 1) occurred near the time of Paleoproterozoic metamorphism and partial melting and is responsible for the extreme HFSE enrichment and growth of zircon and high-niobian rutile.
		A second thermal perturbation and concomitant carbonatite metasomatism (Type 2) occurred in the period 1.0-1.3 Ga and is recorded in relatively consistent whole rock eclogite model Nd ages and secondary U-Pb zircon upper intercept dates.
		The metasomatism was not related to the major Archean melting events, or to the later kimberlite formation as the reconstructed REE pattern of the metasomatic component does not match that of trondjemite-tonalite-granodiorite melts or host Jericho kimberlite.
	www.venuewest.com /8ikc/s2post.htm (5633 words)

	Alteration at Juneau, Alaska
		Calcic pelitic schists from the contact aureole of the Grand Island pluton, in the Juneau Gold Belt, southeast Alaska, contain garnets that display compositional zoning that is the result of episodic metasomatism (Stowell et al., 1996).
		Metasomatism is consistent with andradite garnet found in veins in the same outcrop.
		Repeated metasomatism may have been the consequence of repeated intrusion by phases of the Grand Island diorite.
	www.geo.ucalgary.ca /~tmenard/ores/alaskaSeg.html (245 words)

	Metasomatism Rocks & Minerals - Find Articles (Site not responding. Last check: )
		The susceptibility of a rock to metasomatism depends partly on its mineralogical and structural characteristics and partly on the characteristics of the fluid (i.e., temperature, pressure, pH, oxygen-reduction potential, and water/rock ratio).
		An excellent example of metasomatism is the formation of a skarn (Rakovan 2003), wherein Si from an intruded magma is added to a limestone, usually through the activity of hydrothermal fluids, and combines with Ca to form the Ca-silicate minerals characteristic of skarns.
		A classic example with an interesting history is the metasomatic replacement of limestones in the Magdalena mining district in Socorro County, New Mexico (Loughlin and Koschmann 1942).
	findarticles.com /p/articles/mi_m0GDX/is_1_80/ai_n8694220 (824 words)

	Student Publications & Presentations (Site not responding. Last check: )
		Although the effects of metasomatism are apparent in most Floreana basalts, normally-polarized lavas may have been affected to a greater extent by the metasomatism than the older flows.
		Floreana is distinct from the rest of the Galapagos Archipelago in its explosive history, abundant mantle xenoliths, extensive evidence for contributions from metasomatic fluids, and ITE-enriched composition of its mantle source.
		We propose that the ubiquitous metasomatic processes may be responsible for both the structural and geochemical anomalies observed on Floreana and may be the primary distinguishing characteristic of this end-member in Galapagos mantle plume compositions.
	departments.colgate.edu /geology/students/research04/kolabs.htm (354 words)

	[No title] (Site not responding. Last check: )
		The process, known as "impact metasomatism," has long been proposed for Mars, and these carbonates lend credence to its importance.
		Mars' surface is rich in carbon dioxide, commonly known as dry ice, at its poles and in ice and frost on the planet's surface.
		During impact metasomatism, an asteroid smashes into the planet's surface and crushes the rock beneath, creating miles of interconnected fractures and ground-up target rocks.
	www.case.edu /pubs/cnews/7-18/nature.htm (486 words)

	Processes of Metamorphism (Site not responding. Last check: )
		metasomatism The circulation of hot, watery fluids, called hydrothermal fluids, through a body of rock can alter the rock's composition by removing elements from the rock and/or introducing new elements into the rock.
		This is called metasomatism, and it can occur as hydrothermal fluids are extruded from a body of magma into the surrounding rock, or as groundwater circulates close to a body of magma and then moves upward into overlying rock.
		Rich deposits of copper and iron have resulted from metasomatism, so this process is of major interest to mining companies.
	seis.natsci.csulb.edu /bperry/PROCESSES.htm (363 words)

	v12c-0997 in fm01 (Site not responding. Last check: )
		Metasomatism, which is most strongly exhibited in HLCO xenoliths, involves melt/wall-rock reactions with formation of clinopyroxene at the expense of orthopyroxene, Ca-metasomatism [leading to (CaO/Al2O3)rock$>>$1], enrichment in incompatible trace elements (e.g.
		The metasomatism is associated with the early part of the Canary Islands magmatic event.
		Equilibration with the metasomatic fluids was established with respect to the LREEs in the garnets, whereas the M-HREEs were only partially re-equilibrated due to their slower diffusion rates.
	www.agu.org /cgi-bin/SFgate/SFgate?&listenv=table&multiple=1&range=1&directget=1&application=fm01&database=/data/epubs/wais/indexes/fm01/fm01&maxhits=200&="V12C-0997" (9587 words)

	[No title] (Site not responding. Last check: )
		Mars' surface is rich in carbon dioxide, commonly known as dry ice, at its poles and in ice and frost on the planet's surface.
		During impact metasomatism, an asteroid smashes into the planet's surface and crushes the rock beneath, creating miles of interconnected fractures and ground-up target rocks.
		Researchers have accounted for this by calling for processes like impact metasomatism as well as more "terrestrial" processes like weather or deposition of limestone from groundwater or even Martian oceans.
	www.cwru.edu /pubs/cnews/7-18/nature.htm (486 words)

Try your search on: Qwika (all wikis)