| Mafic rock | |
 Troctolite 76535 from theApollo 17 landing site | |
| Composition | |
|---|---|
| olivine, calcicplagioclase, minorpyroxene |
Troctolite/ˈtrɒktəlaɪt/ (from Greek τρώκτης 'trout' and λίθος 'stone') is amaficintrusive rock type. It consists essentially of major but variable amounts ofolivine and calcicplagioclase along with minorpyroxene. It is an olivine-richanorthosite, or a pyroxene-depleted relative ofgabbro. However, unlike gabbro, no troctolite corresponds in composition to a partial melt of peridotite. Thus, troctolite is necessarily acumulate of crystals that have fractionated from melt.[1]
Troctolite is found in somelayered intrusions such as in theArcheanWindimurra intrusion ofWestern Australia, theVoisey's Baynickel-copper-cobalt magmaticsulfide deposit of northernLabrador,[2] theStillwater igneous complex ofMontana, theDuluth Complex of the North American Midcontinent Rift,[3] and theTertiaryRhum layered intrusion of the island ofRùm,Scotland.[4] Troctolite is also found, for example, in theMerensky Reef of theBushveld Igneous Complex,South Africa and in theLizard complex inCornwall.[5]
.png) | Thisigneous rock-related article is astub. You can help Wikipedia byexpanding it. |