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Topic: Tephrite

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Tonalite

Latite

Igneous rock

Phonolite

Diorite

Rhyolite

Andesite

Syenite

Trachyte

Serpentinite

Rock (geology)

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Amphibolite

Eclogite

	Goldschmidt 2007 Field Trips
		A deeply dissected scoria cone (Eppelsberg) erupted parental basanite magma and deposited phreatomagmatic surges at the base, constructed the main strombolian cone which is overlain by late surge deposits and layers from Hawaiian fire fountains.
		An intermediate hauyne-bearing tephrite has been quarried since Roman times.
		Quarries expose the top and base of the flow and cut into ancient underground caverns from mining the millstones.
	www.goldschmidt2007.org /excursions.php (2168 words)

	Tephrite - Wikipedia, the free encyclopedia
		Tephrite is an igneous, volcanic (extrusive) rock, of felsic composition, with aphanitic to porphyritic texture.
		Occurrences include phonolite-tephrite Mt. Vulture, Basilicata, Italy, basanite–tephrite intrusions in Namibia, and leucite nepheline tephrite from Hamburg, Germany.
		This page was last modified 09:45, 14 June 2006.
	en.wikipedia.org /wiki/Tephrite (79 words)

	Olympus Microscopy Resource Center: Polarized Light Microscopy Gallery - Leucite Nepheline Tephrite
		Leucite-tephrite is a type of igneous rock in which olivine is absent and plagioclase feldspar is present.
		When nepheline, the most common feldspathoid mineral in the world, also occurs in the rock, the basalt is described as a leucite nepheline tephrite.
		Extremely rare, leucite nepheline tephrite, which may exhibit an aphanitic to porphyritic texture, is best known from Hamberg, Germany.
	www.olympusmicro.com /galleries/polarizedlight/pages/leucitenephelinetephritesmall.html (210 words)

	Abstract CMP 1998-1 (Site not responding. Last check: 2007-10-28)
		Duraznero crater erupted tephrite for 14 days and shut down upon the opening of Llano del Banco, a fissure that issued first tephrite and, after 3 days, basanite.
		The tephrites and basanites from Duraznero and Llano del Banco show narrow compositional ranges and define a bimodal suite.
		Most of the erupted tephrite and basanite ascended from mantle depths within hours to days without prolonged storage in crustal reservoirs.
	www.palmod.uni-bremen.de /~akluegel/abs_jgr2000.htm (297 words)

	Kaiserstuhl
		Die petrographische Zusammensetzung der Tephrite verriiert in gewissen Grenzen, ist aber immer durch das Vorherrschen von Titanaugitinsprenglingen (25-35 Vol%) charakterisiert.
		Leucit ist primär der wichtigste Feldspatvertreter in den Tephriten.
		Tephrite gehören zu den ältesten und jüngsten Produkten des Kaiserstuhlvulkanismus und es kann angenommen werden, dass dieses Magma während der gesamten Zeitspanne der magmatischen Aktivität verfügbar war.
	omnibus.uni-freiburg.de /~weisenbt/9Kaiserstuhl/Excursion.html (1199 words)

	MTU-VP - Fogo GVN (Site not responding. Last check: 2007-10-28)
		The total volume of lava extruded was ~60-100 x 10^6 m^3, assuming lava flow thicknesses of ~9-15 m; the known range was from 1 to >20 m.
		Based on six major-element XRF analyses, the lava flow erupted during the first night (3 April) was determined to be a differentiated kaersutite-bearing phonotephrite (IUGS system), whereas later lava flows and spatter were more primitive tephrite basanite.
		Fogo Island consists of a single massive volcano with an 8-km-wide caldera breached to the E. The central cone was apparently almost continuously active from the time of Portuguese settlement in 1500 A.D. until around 1760.
	www.geo.mtu.edu /volcanoes/africa/fogo/gvn/fogo.v20n11_12.html (194 words)

	Compositional variation during monogenetic volcano growth and its implications for magma supply to continental volcanic ...
		by a second batch of basanitic melt, with tephrite rising to
		we infer that fractionation to tephrite would have required
		the presence in the dyke head of buoyant tephrite captured during
	jgs.geoscienceworld.org /cgi/content/abstract/160/4/523 (304 words)

	Untitled Document (Site not responding. Last check: 2007-10-28)
		The 1944 products range in composition from phonolitic tephrite to tephrite.
		The lower portion of the pyroclastic sequence includes both brownish vesicular and dark dense lapilli juvenile clasts.
		The presence of periclase in the Mg-Skarn could suggest hypo-abyssal conditions with maximum pressures of 1,000 bars.
	www.ov.ingv.it /volcanology/vesuvio/petrologia.htm (362 words)

	Fluorapatite from Tephrite outcrop, Mt. Vulture, Potenza Province, Basilicata, Italy
		Fluorapatite from Tephrite outcrop, Mt. Vulture, Potenza Province, Basilicata, Italy
		Tephrite outcrop, Mt. Vulture, Potenza Province, Basilicata, Italy
		Click here to view Tephrite outcrop, Mt. Vulture, Potenza Province, Basilicata, Italy
	www.mindat.org /locentry-306436.html (61 words)

	Pompeii, VESUVIUS ERUPTS, Click2Disasters.com
		Dust, ashes, cinders, tephra and rocks fell on the town for about 8 hours.
		Heaps of tephrite (rocks) landing on houses caused roofs to collapse.
		Buildings began to crack diagonally from in-plane loading and shear deformation.
	www.click2disasters.com /pompeii/pompeii_ch5.htm (340 words)

	Abstact LXXII, 2003
		The phase V is related to the Archi di Pontecchio Synthem (200-155 ky) and characterised by prevailing strombolian deposits with a composition ranging from phonolitic tephrite to tephrite.
		The magmatic cycle (154-134 ky) is dominated by pyroclastic fall and lava flows with a variable composition from phonolitic tephrite to potassic trachibasalt.
		The phreatomagmatic cycle marked the end of the volcanic activity (<134 ky) in the northern sector of the Sabatinian District and produced small, single eruptive centres (maars) or coalescent craters which are aligned in a NW-SE regional fracture system at a right angle to the tectonic orientation of the initial Sabatinian Volcanic activity.
	tetide.geo.uniroma1.it /riviste/permin/abstract03-3.htm (1452 words)

	Bulletin 61 Table of Contents
		'C' series - mainly anorthoclase porphyries; lavas of phonolite composition and some tephrite.
		In the case of 'A' series, precipitation of mainly plagioclase and pyroxene from andesite produces rhyolite; and for 'C' series, precipitation of mainly pyroxene and some biotite from tephrite produces phonolite.
		Rocks of 'B' series are intermediate in composition to 'A' and 'C' and were probably formed by mixing of magmas.
	www.em.gov.bc.ca /Mining/geolsurv/publications/Bulletins/Bull61/toc.htm (429 words)

	Italian Volcanoes
		The oldest rock is said to be about 300,000 years old, probably from Somma.
		Rocks found at Vesuvius are called tephrite, basalts containing calcic plagioclase, augite, and nepheline or leucite.
		The eruptions begin with an effusive phase, where lava pours out of fractures in the cone, then after a few days it becomes explosive with lava spewing out from the cone (2-4 Km high).
	www.uwm.edu /People/mtharris/Lyell03/CN12.htm (520 words)

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