Anorthosite is medium to coarse grained and has an adcumulate texture. It is composed of plagioclase (90%) slightly sericitized in places, slightly serpentinized orthopyroxene and clinopyroxene. Gabbro and gabbronorite are fine to medium grained, homogeneous and have a mesocumulate texture.

The Laramie anorthosite complex includes three anorthositic plutons: the Poe Mountain, Chugwater, in zones of intense alteration, a texture suggesting that.

Mafic granulites typically show granoblastic texture with sieved as well as coronal garnets, flakes of biotite, rounded grains of sphene. 2591.13 Mottled anorthosite, mottles increasing in size and frequency downwards. 2592.25 Mottled anorthosite, grading into… 2594.20 Leucogabbronorite. 2597.35 Mottled anorthosite, variable textures such as the size of mottles, orthopyroxene-clinopyroxene. textures, developed in fine-grained to medium-grained gabbro and melagabbro layers; (4) size grading, most commonly developed in megacrystic anorthosite layers; (5) "spotted" texture in which pyroxene forms equant crystals that are more resistant to weathering than the plagioclase and, consequently, appear as "spots"; and (6) variable texture The anorthosite highlands of the Moon are primary crust, formed as plagioclase crystallized out of the Moon's initial magma ocean and floated to the top; however, it is unlikely that Earth followed a similar pattern, as the Moon was a water-less system and Earth had water. Lunar anorthosite 15415 consists almost entirely of anorthite (homogeneous anorthite 96.6 molecule percent), with accessory diopsidic augite and traces of hypersthene, ilmenite, and a silica mineral. The rock has had a complex metamorphic history.

However, Typical texture of undeformed Archean anorthosite showing megacrysts of calcic plagioclase in a mafic groundmass, Pipestone Lake, Manitoba. From Ashwal (1993, Fig. 2.2). 1980-01-01 Such textures have been quantified in a troctolite-anorthosite from the Proterozoic Lac-St-Jean anorthosite complex, Canada. Crystal size distributions (CSDs) indicate that initially plagioclase nucleated and grew in an INTRODUCTIONenvironment of linearly increasing undercooling, producing a straight-The textures of plutonic rocks are one of their most line CSD. 1994-07-01 The textures of plagioclase crystals within large olivine oikocrysts preserve the sequence of the formation of anorthosite. Such textures have been quantified in a troctolite-anorthosite from the 2004-05-01 1994-07-01 Inequigranular anorthosite.

Natural stone from Norway. Stone type; Anorthosite. Available as "cut to size" for large projects upon request. Available in pre-produced sizes (mm): 300x300, 300x600, 400x600, 400x800, 600x600, 600x1200. Thickness; 10mm, 15mm, 20mm. Recommended suface finishes for flooring: Polished, Silk/Leather, Honed. Weight 2700 kg/m3 .

The mineralogy and texture of gabbros, norites, diabases, and basalts indicates that they are probably The textures of naturally deformed rocks present fingerprints of the earth's history and provide information on deformation and recrystallization processes during tectonometamorphic events. This study is concerned with anorthosites, i.e. cumulate rocks containing >90% plagioclase [3] , originating from the large Gruber anorthosite in Central Dronning Maud Land, Antarctica.

anorthosite (~98% plagioclase). Dixon and Papike. (1975) pictured relict “triple junction” texture between large grains of plagioclase (1 – 3 mm) with small grains .

Gabbros and norites are found in sills, dikes, stocks, lopoliths, and other bodies. The mineralogy and texture of gabbros, norites, diabases, and basalts indicates that they are probably The textures of naturally deformed rocks present fingerprints of the earth's history and provide information on deformation and recrystallization processes during tectonometamorphic events. This study is concerned with anorthosites, i.e. cumulate rocks containing >90% plagioclase [3] , originating from the large Gruber anorthosite in Central Dronning Maud Land, Antarctica. Anorthite is a rare member of the Feldspar group.Italian Localities include Monte Somma, Mount Vesuvius; Val Schiesone, Sondrio; and Val Di Fassa, Trento.

More information about these rocks is included in chapters 11, 13, and 14 of Moorhouse. This is the first examination of intrusive rocks you will make. There are two 2010-01-01 · Free Online Library: Igneous structure and texture of the ~1.3 Ga Hosenbein anorthosite pluton (Nain, Labrador) and implications for the crystallization of massif-type anorthosite.(Report) by "Atlantic Geology"; Earth sciences Crystal structure Case studies Models Crystallization Research Crystals Structure Magma Natural history Plutonic rocks Observations Properties The textures of plagioclase crystals within large olivine oikocrysts preserve the sequence of the formation of anorthosite. Such textures have been quantified in a troctolite–anorthosite from the Proterozoic Lac-St-Jean anorthosite complex, Canada.
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30 cm The Laramie anorthosite complex includes three anorthositic plutons: the Poe Mountain, Chugwater, in zones of intense alteration, a texture suggesting that.

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Quantitative Texture Analysis of an Anorthosite— Application to Thermal Expansion, Young's Modulus and Thermal Stresses.pdf Available via license: CC BY 3.0 Content may be subject to copyright.

The Lac Rouvray anorthosite mass forms a part of the Lac St. Jean massif. Attempts to subdivide the Lac Rouvray mass into mappable types based on mafic mineral content and total rock textures failed.

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In most of this anorthosite, andesine megacrysts with bytownite inclusions are embedded in a ghost-like, earlier fine-grained texture. Extinction contrast of the

Plagioclase makes up more than 95% of the rock. Orthopyroxene and augite are the most abundant accessory minerals, being present in roughly equal amounts in the available thin sections. Many of the anorthosite samples returned by astronauts from the Moon have a similar crumbly texture, not because of weathering by water but due to impact shock and shattering by meteorite bombardment. You'll notice a range of colors here. Anorthosite-mangerite-charnockite-granite (AMCG) magmatism is widespread throughout the Mesoproterozoic Grenville Province (), and nowhere else on Earth are massif anorthosite complexes, which underlie approximately ∼20% of the area, so abundant (Fig. 1; Corriveau et al., 2007; Morisset et al., 2008).

Alkali suite anorthosites and norites are the second most common plutonic rock have equilibration temperatures of 950–1100 °C, relict igneous textures and,

Some crystals have euhedral form, some have poorly developed faces and others have no crystal form at all. 6. Textures 7.

The textures of plagioclase crystals within large olivine oikocrysts preserve the sequence of the formation of anorthosite.