Blairmorite

Blairmorite
Extrusive igneous rock
	A specimen of blairmorite from the Crowsnest Formation. The amber mineral is analcime, the pale mineral is sanidine and the small black minerals are melanite garnet.
Composition
Primary	Analcime, sanidine, pyroxene
Secondary	Titanite, melanite, nepheline

Blairmorite is a very rare^[1] porphyritic volcanic rock named after the community of Blairmore in southwestern Alberta, Canada.^[2]^[3] It is characterized by dominant analcime phenocrysts in a matrix of analcime, sanidine and alkalic pyroxene with accessory titanite, melanite and nepheline. It is a leucocratic variety of analcimite (a foidite).^[4] Blairmorite has also been described as an analcime-rich variety of phonolite.^[5]^[6]

This extrusive igneous rock is known from only two geological formations worldwide. The foremost blairmorite occurrence is the Crowsnest Formation in the Canadian province of Alberta where it is associated with agglomerates and tuffs from explosive eruptions. The other locality is the Lupata Gorge in Mozambique.^[2]

References[edit]

^ MacKenzie, W.S., Donaldson, C.H. and Guilford, C. (1982). Atlas of igneous rocks and their textures. Harlow: Longman. p. 121. ISBN 0-582-30082-7.{{cite book}}: CS1 maint: multiple names: authors list (link)
^ ^a ^b Pearce, T.H. (1993). "Analcime phenocrysts in igneous rocks: Primary or secondary? – Discussion" (PDF). American Mineralogist. 78: 225–229.
^ Johannsen, A. 1933. A descriptive petrography of the igneous rocks, Appendix III, p. 244. Univ. of Chicago Press.
^ Le Maitre, R.W. (editor) (2002). Igneous Rocks — A Classification and Glossary of Terms (2nd ed.). Cambridge: Cambridge University Press. pp. 55, 64. ISBN 0-521-66215-X. {{cite book}}: |author= has generic name (help)
^ Peterson, T.D.; Currie, K.L. (1993). Analcite-bearing igneous rocks from the Crowsnest Formation, southwestern Alberta (Current Research report 93-B1) (PDF). Geological Survey of Canada. pp. 51–56.
^ Deer, W.A.; Howie, R.A.; Zussman, J. (2013). An Introduction to the Rock-Forming Minerals (3rd ed.). London: Mineralogical Society. ISBN 9780903056274.

This igneous rock-related article is a stub. You can help Wikipedia by expanding it.

This volcanology article is a stub. You can help Wikipedia by expanding it.

[MacKenzieEtAl1982-1] MacKenzie, W.S., Donaldson, C.H. and Guilford, C. (1982). Atlas of igneous rocks and their textures. Harlow: Longman. p. 121. ISBN 0-582-30082-7.{{cite book}}: CS1 maint: multiple names: authors list (link)

[Pearce-2] Pearce, T.H. (1993). "Analcime phenocrysts in igneous rocks: Primary or secondary? – Discussion" (PDF). American Mineralogist. 78: 225–229.

[3] Johannsen, A. 1933. A descriptive petrography of the igneous rocks, Appendix III, p. 244. Univ. of Chicago Press.

[LeMaitre2002-4] Le Maitre, R.W. (editor) (2002). Igneous Rocks — A Classification and Glossary of Terms (2nd ed.). Cambridge: Cambridge University Press. pp. 55, 64. ISBN 0-521-66215-X. {{cite book}}: |author= has generic name (help)

[PetersenCurrie1993-5] Peterson, T.D.; Currie, K.L. (1993). Analcite-bearing igneous rocks from the Crowsnest Formation, southwestern Alberta (Current Research report 93-B1) (PDF). Geological Survey of Canada. pp. 51–56.

[DeerHowieZussman2013-6] Deer, W.A.; Howie, R.A.; Zussman, J. (2013). An Introduction to the Rock-Forming Minerals (3rd ed.). London: Mineralogical Society. ISBN 9780903056274.

[1]

[2]

[3]

[4]

[5]

[6]

v t e Volcanoes
Types	Caldera Cinder cone Complex volcano Cryovolcano Cryptovolcanic structure Fissure vent Lava cone Lava dome Maar Mud volcano Parasitic cone Pyroclastic cone Pyroclastic shield Rootless cone Shield volcano Somma volcano Stratovolcano Subglacial volcano Submarine volcano Supervolcano Volcanic cone
Volcanic rocks	Agglomerate Andesite Basalt Basaltic andesite Benmoreite Blairmorite Cinder Dacite Felsite Ignimbrite Komatiite Latite Leucitite Nephelinite Obsidian Phonolite Phonotephrite Pumice Rhyodacite Rhyolite Tephriphonolite Trachyandesite Trachybasalt Trachyte Tuff
Lists and groups	Hotspot Lists of volcanoes Eruptions by death toll Decade Volcanoes Volcanic arc Volcanic belt Volcanic field monogenetic polygenetic
Category Commons Portal WikiProject

v t e Types of rocks
Igneous rock	Adakite Andesite Alkali feldspar granite Anorthosite Aplite Basalt Basaltic trachyandesite Mugearite Shoshonite Basanite Blairmorite Boninite Carbonatite Charnockite Enderbite Dacite Diabase Diorite Napoleonite Dunite Essexite Foidolite Gabbro Granite Granodiorite Granophyre Harzburgite Hornblendite Hyaloclastite Icelandite Ignimbrite Ijolite Kimberlite Komatiite Lamproite Lamprophyre Latite Lherzolite Monzogranite Monzonite Nepheline syenite Nephelinite Norite Obsidian Pegmatite Peridotite Phonolite Phonotephrite Picrite Porphyry Pumice Pyroxenite Quartz diorite Quartz monzonite Quartzolite Rhyodacite Rhyolite Comendite Pantellerite Scoria Shonkinite Sovite Syenite Tachylyte Tephriphonolite Tephrite Tonalite Trachyandesite Benmoreite Trachybasalt Hawaiite Trachyte Troctolite Trondhjemite Tuff Websterite Wehrlite
Sedimentary rock	Argillite Arkose Banded iron formation Breccia Calcarenite Chalk Chert Claystone Coal Conglomerate Coquina Diamictite Diatomite Dolomite Evaporite Flint Geyserite Greywacke Gritstone Itacolumite Jaspillite Laterite Lignite Limestone Lumachelle Marl Mudstone Oil shale Oolite Phosphorite Sandstone Shale Siltstone Sylvinite Tillite Travertine Tufa Turbidite Varve Wackestone
Metamorphic rock	Anthracite Amphibolite Blueschist Cataclasite Eclogite Gneiss Granulite Greenschist Hornfels Calcflinta Itabirite Litchfieldite Marble Migmatite Mylonite Metapelite Metapsammite Phyllite Pseudotachylite Quartzite Schist Serpentinite Skarn Slate Suevite Talc carbonate Soapstone Tectonite Whiteschist
Specific varieties	Adamellite Appinite Aphanite Borolanite Blue Granite Epidosite Felsite Flint Ganister Gossan Hyaloclastite Ijolite Jadeitite Jasperoid Kenyte Lapis lazuli Larvikite Litchfieldite Llanite Luxullianite Mangerite Novaculite Pietersite Pyrolite Rapakivi granite Rhomb porphyry Rodingite Shonkinite Taconite Tachylite Teschenite Theralite Unakite Variolite Wad

Composition
Extrusive igneous rock
A specimen of blairmorite from the Crowsnest Formation. The amber mineral is analcime, the pale mineral is sanidine and the small black minerals are melanite garnet.
Primary	Analcime, sanidine, pyroxene
Secondary	Titanite, melanite, nepheline

Blairmorite

References[edit]

Premium Membership

€4.95

Create a Premium Account quick and easy

Save your Favourite Pages

Listen to any page in Audio

Colour Night Mode