Troctolite/ˈtrɒktəlaɪt/ (from Greek τρώκτης 'trout' and λίθος 'stone') is a mafic intrusive rock type. It consists essentially of major but variable amounts of olivine and calcic plagioclase along with minor pyroxene. It is an olivine-rich anorthosite, or a pyroxene-depleted relative of gabbro. However, unlike gabbro, no troctolite corresponds in composition to a partial melt of peridotite. Thus, troctolite is necessarily a cumulate of crystals that have fractionated from melt.[1]
Troctolite is found in some layered intrusions such as in the Archean Windimurra intrusion of Western Australia, the Voisey's Bay nickel-copper-cobalt magmatic sulfide deposit of northern Labrador,[2] the Stillwater igneous complex of Montana, the Duluth Complex of the North American Midcontinent Rift,[3] and the Tertiary Rhum layered intrusion of the island of Rùm, Scotland.[4] Troctolite is also found, for example, in the Merensky Reef of the Bushveld Igneous Complex, South Africa and in the Lizard complex in Cornwall.[5]
^Emeleus, C. H.; Troll, V. R. (2014-08-01). "The Rum Igneous Centre, Scotland". Mineralogical Magazine. 78 (4): 805–839. Bibcode:2014MinM...78..805E. doi:10.1180/minmag.2014.078.4.04. ISSN 0026-461X.
^Sulphide segregation in the Mushuau Intrusion of northern Labrador as recorded by nickel-in-olivine magmatic stratigraphy Archived 2017-10-23 at the Wayback Machine abstract, BRADLEY, L.A. and SYLVESTER, P.J., Department of Earth Sciences, Memorial University of Newfoundland, St. John's, NF, A1B 3X5
^Paces, James B.; Miller, James D. (1993). "Precise U-Pb ages of Duluth Complex and related mafic intrusions, northeastern Minnesota: Geochronological insights to physical, petrogenetic, paleomagnetic, and tectonomagmatic processes associated with the 1.1 Ga Midcontinent Rift System". Journal of Geophysical Research: Solid Earth. 98 (B8): 13997–14013. Bibcode:1993JGR....9813997P. doi:10.1029/93JB01159. ISSN 0148-0227.
^http://www.turnstone.ca/rhumal.htm Troctolite (allivalite): Isle of Rhum, northwestern Scotland
Troctolite /ˈtrɒktəlaɪt/ (from Greek τρώκτης 'trout' and λίθος 'stone') is a mafic intrusive rock type. It consists essentially of major but variable amounts...
Troctolite 76535 is a lunar sample discovered and collected on the Apollo 17 mission in 1972 in the Taurus–Littrow valley. It has a mass of about 156 grams...
Rhode Island and a specific type of plutonic rock called a melanocratic troctolite, or melatroctolite. It can be found in a 4-acre (0.016 km2) lot in Blackstone...
silica-undersaturated volcanic rock; essentially a feldspathoid-bearing rhyolite Troctolite – Igneous rock – A plutonic ultramafic rock containing olivine, pyroxene...
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orthopyroxene, with less than 5% each of hornblende, clinopyroxene, or olivine. Troctolite is composed almost entirely of plagioclase and olivine, with less than...
the dunites, peridotites and pyroxenites. Other rare varieties include troctolite which has a greater percentage of calcic plagioclase. These grade into...
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at geology station 6 near the base of the North Massif; the sample, a troctolite, was later identified as the oldest known "unshocked" lunar rock, meaning...
the Glen Mountains Layered Complex, consists of gabbro, anorthosite and troctolite. Recent high-precision dating yields an age of 532.49 ± 0.15 Ma. These...
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different types of magmas that would give rise to the Mg-suite norites and troctolites began to form, although the exact depths at which this occurred are not...
magnesian suite (or "Mg-suite") consists of dunites (>90% olivine), troctolites (olivine-plagioclase), and gabbros (plagioclase-pyroxene) with relatively...
examples being the Bushveld igneous complex, South Africa, the Voisey's Bay troctolite intrusive complex in Canada, the Duluth gabbro, in North America, and...
geologist in the astronaut corps—collected the rock sample designated Troctolite 76535, which has been called "without doubt the most interesting sample...
was 736 K (865 °F). The surface sample was found to be an anorthosite–troctolite rock, rarely found on Earth, but present in the lunar highlands, leading...
736 K (463 °C; 865 °F). The surface sample was found to be an anorthosite-troctolite. The lander transmitted data from the surface for 56 minutes.[citation...
Jersey, United States Gneiss boulder balanced on three smaller boulders. Troctolite 76535 Lunar Sample Laboratory Facility, Houston, Texas, United States...
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