词条 | Ijolite |
释义 |
The pyroxene is {{clarify span|text=morphic|explain=obscure term|date=January 2017}}, yellow or green, and is surrounded by formless areas of nepheline. The accessory minerals are apatite, cancrinite, calcite, titanite and iivaarite, a dark-brown titaniferous variety of melanite-garnet. This rock is the plutonic and holo-crystalline analogue of the nephelinites -volcanic equivalent and nepheline-dolerites; it bears the same relation to them as the nepheline syenites have to the phonolites. A leucite-augite rock, resembling ijolite except in containing leucite in place of nepheline, is known to occur at Shonkin Creek, near Fort Benton, Montana, and has been called missourite, but is now regarded as a variety of leucitite.[2] References1. ^{{cite web |url=http://uppslagsverket.fi/sv/sok/view-103684-RamsayWilhelm |title=Ramsay, Wilhelm |last=Lindberg |first=Johan |date=January 19, 2011 |website=Uppslagsverket Finland |publisher= |access-date=November 30, 2017 |language=Swedish}} 2. ^{{cite book | title=Petrology and Genesis of Leucite-Bearing Rocks | publisher=Springer-Verlag | author=Gupta, A.K and Yagi, K. | year=1980 | location=Berlin | isbn=978-3-642-67552-2}}
1 : Plutonic rocks |
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