"dacite." YourDictionary, n.d. Web. 14 January 2019. <https://www.yourdictionary.com/dacite>.
dacite. (n.d.). Retrieved January 14th, 2019, from https://www.yourdictionary.com/dacite
A fine-grained light gray volcanic rock consisting primarily of quartz, plagioclase feldspar, and potassium feldspar, and also containing biotite, hornblende, or pyroxene. It is the fine-grained equivalent of granodiorite.
The lavas and ashes ejected by these volcanoes consist of liparite, dacite, andesite and basalt.
The Cainozoic volcanic history of New Zealand begins in the Oligocene, when the high volcanic domes of Dunedin and Banks Peninsula were built up. The Dunedin lavas including tephrites and kenytes correspond to the dacite eruptions in the volcanic history of Victoria.
The tinguaites and solvsbergites of Port C y gnet, south of Hobart, may be of this age; they are intrusive in Carboniferous rocks, and there is no evidence of their precise date; but their resemblance to the rocks associated with the geburite-dacite of Victoria suggests that they may belong to.