= Mafics). The name is from anorthose, an old name for triclinic feldspars. Anorthosite is often associated with gabbro. 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

Sep 10, 2014 The lunar highland samples with pure anorthosite and the PAN Images of the magnesian anorthosite with granulitic breccia texture in Dhofar 

Some crystals have euhedral form, some have poorly developed faces and others have no crystal form at all. 4. 2010-01-01 2000-03-01 Quantitative texture analysis of an anorthite (polycrystalline plagioclase feldspar) has been under taken using an optical microscope equipped with a universal stage. The microstructure was studied on three orthogonal sections. The microstructural shape analysis suggests an axial fabric which is confirmed by texture analysis. The texture has two major components, group I with ⊥(001 osti.gov journal article: lunar anorthosite 15415: texture, mineralogy, and metamorphic history. Texture investigations on geological anorthosite specimens with the triclinic plagioclase-type structure have been performed by neutron diffraction po… goniometry with a position sensitive detector to anorthosite (Wenket al., 1986) has created new possibilities for the texture analysis of feldspar rocks.

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Stillwater Complex, Montana. Plane/cross-polarized light, field width is 6 mm. STW-37 Anorthite is a rare member of the Feldspar group.Italian Localities include Monte Somma, Mount Vesuvius; Val Schiesone, Sondrio; and Val Di Fassa, Trento. Japan produces excellent crystals thinly coated with a dark layer of lava at Miyaki Jima (Miyaki Island), Tokyo Prefecture. Anorthosite is by definition an igneous rock consisting of 90-100% plagioclase feldspar.

However, the typical garnet symplectitic textures are totally absent in BAC, unlike those present in the Sittampundi anorthosite complex [30] [41] . Mafic granulites typically show granoblastic texture with sieved as well as coronal garnets, flakes of biotite, rounded grains of sphene.

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 .

Figure 20-2 Anorthosite is a white to light gray-colored intrusive igneous rock. Major minerals of anorthosite include just feldspar. Anorthosite has a coarse-grained texture due to slow cooling underground.

Quantitative texture analysis of an anorthite (polycrystalline plagioclase feldspar) has been under takenusinganoptical microscopeequippedwithauniversal stage. Themicrostructurewasstudiedon three orthogonal sections. The microstructural shape analysis suggests an axial fabric which is confirmedbytexture analysis.

The mesocumulate texture that characterizes leucogabbronorite-leuconorite is defined by higher proportions of intercumulus pyroxene and Fe-Ti oxide. Quantitative texture analysis of an anorthite (polycrystalline plagioclase feldspar) has been under takenusinganoptical microscopeequippedwithauniversal stage. Themicrostructurewasstudiedon three orthogonal sections. The microstructural shape analysis suggests an axial fabric which is confirmedbytexture analysis. Commonly, anorthosites form at the tops of modally graded layers on the scale of several meters up to 100 meters or more.

The Layered Troctolite terminates abruptly along sinuous boundaries against Massive Anorthosite, which has a texture similar to anorthositic patches in both types of troctolite. Massive anorthosite Olivine oikocrysts - plagioclase chadocryst orientations indicated schematically where visible 20 cm Fig. 2. Thus age, composition and magmatic texture distinguish Proterozoic massif-type from Archean megacrystic anorthosites. Aside from anorthosite, the dominant rock types of anorthosites massif, include leucogabbro, leuconorite and leucotroctolite, with minor gabbroic rocks. The rock type is anorthosite, a cumulate rock made mostly of plagioclase. Cumulate rocks typically have the same minerals about the same size.
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In this case, grain textures look somewhat annealed, possibly because of deformation and annealing when it was still very hot. Stillwater Complex, Montana. Plane/cross-polarized light, field width is 6 mm. STW-37 Anorthite is a rare member of the Feldspar group.Italian Localities include Monte Somma, Mount Vesuvius; Val Schiesone, Sondrio; and Val Di Fassa, Trento. Japan produces excellent crystals thinly coated with a dark layer of lava at Miyaki Jima (Miyaki Island), Tokyo Prefecture.

The proportion of ferromagnesian minerals increases from anorthosite to ferrodiorite through leuconorites L'anorthosite est une roche ignée intrusive formée de 90% ou plus de feldspath plagioclase et 10% ou moins de minéraux mafiques comme le pyroxène, l'olivine, l'ilménite et la magnétite. L'anorthosite a communément une texture grenue, souvent pegmatitique. Some of the rock at this location remains strong and competent, but much of it has a brittle crumbly or chalky texture as weathering has begun the process of breaking it down into clay. 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.
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Archean anorthosite complexes in the Superior Province are listed in Table 1. texture. Large, elongate gabbroic bodies are exposed along the northern and 

Labradorescent plagioclase feldspar (Marcy Anorthosite, Mesoproterozoic, 1.16 Ga; Route 3 roadcut south of Bartlett Pond, New York State, USA) 3.jpg 4,000 × 3,000; 8.18 MB 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. The texture reflects at least two episodes of shearing (followed by intense and partial recrystallization, respectively), one episode of cataclastic 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 Feldspar (in anorthosite) Some varieties of gabbro have few dark minerals, and are made almost entirely of plagioclase feldspar. This rock shows the interlocking texture of the feldspars… 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. The Kunene Intrusive Complex (KIC), Namibia, a typical massif-type anorthosite, has not been subjected to a later metamorphic overprint and hence has preserved primary magmatic phases and textures (Ashwal & Twist, 1994; Drüppel et al., 2001, 2007; Mayer et al., 2004). 2591.13 Mottled anorthosite, mottles increasing in size and frequency downwards.