Image Mineraly.sk dacit.jpg thumb 250px Dacite Image Dacite AphaniticQAPF.gif thumb 250px Aphanitic QAPF diagram denoting daciteDacite pron en de sa t is an igneous rock igneous , volcanic rock . It is intermediate ... s and quartz in dacite, and in many other volcanic rocks, are illustrated in the QAPF diagram . Dacite is also defined by silica and alkali contents in the TAS classification . The word dacite comes ... now modern Romania where the rock was first described. Composition Dacite consists mostly of plagioclase ... is composed of plagioclase and quartz. Texture Image Different types of dacite 1200px.JPG thumb 300px Grey, red, black, altered white tan, flow banded pumice dacite In hand specimen many ... context and formation Image Dacite ThinSection USGS.jpg thumb 300px Thin section of a porphyritic dacite from Mount St. Helens Dacite usually forms as an intrusive rock such as a dike geology dike or sill geology sill . Examples of this type of dacite outcrop are found in northwestern Montana and northeastern ... of this is Mount St. Helens in which dacite domes formed from previous eruptions. Dacitic magma is formed .... ref Drummond, M. S. and Defant, M. J., 1990, A model for trondhjemite tonalite dacite genesis ...., Feigenson, M 1991 Dacite Genesis via both Slab Melting and Differentiation Petrogenesis of La Yeguada ... provide insight to the history of the magma. The formation of dacite provides a great deal of information ... of felsic, buoyant, perennial rock from a mafic, dense, short lived one. Dacite s role in the creation of Archean continental crust The process by which dacite forms has been used to explain ... magmas from newly underplated basaltic crust. Nature 362, 144 146. ref Molten dacite magma at K lauea Dacite magma was encountered in a drillhole during geothermal exploration on K lauea in 2005. The magma ... and quenched over a range of 8 m. The dacite magma is a residual melt of the typical basalt magma of K lauea. ref http www.agu.org meetings fm08 fm08 sessions fm08 V23A.html Puna Dacite Magma at Kilauea ... more details
Summary Thin section image in crossed polars of a Dacite sample from a dome in Mount St. Helens . Image by United States Geological Survey, a federal scientific agency. Licensing PD USGov Interior USGS ... more details
Painted Peak is a summit topography peak rising from the north part of Russet Hills in the Gallipoli Heights , Freyberg Mountains . Descriptively named by the New Zealand Antarctic Place Names Committee NZ APC on the proposal of P.J. Oliver , New Zealand Antarctic Research Program NZARP geologist who studied the feature, 1981 82. Ignimbrite and dacite breccia cut by dikes of andesite and dacite give the peak many colors. usgs gazetteer antarctica geo stub coord 72 27 S 163 45 E display title Category Mountains of Antarctica ... more details
This high aerial view of Negit Island is toward the southwest. Three separate vents each erupted individual dacite lava flows to form three parallel elongate flows. The vents are located on the highest parts of the flows. The lava flows erupted between about 2,000 and 200 years ago. The northwest edge of Paoha Island is visible in upper left. U.S. Geological Survey photo by Roy Bailey. PD USGov Interior USGS http lvo.wr.usgs.gov gallery 30714277 016 caption.html ... more details
In igneous petrology an intermediate composition refers to the chemical composition of a rock that has 52 63 wt Silicon dioxide SiO sub 2 sub being an intermediate between felsic and mafic compositions. Typical intermediate rocks include andesite , dacite and trachyandesite among volcanic rocks and diorite and granodiorite among plutonic rocks. Igneous rocks Category geochemistry Category Igneous rocks Category Intermediate rocks petrology stub de Intermedi res Gestein nl Intermediair gesteente sk Intermedi rna hornina ... more details
Pebble Creek Formation is a volcano volcanic formation in the Garibaldi Volcanic Belt created when Mount Meager erupted about 2,350 years ago and by two Rock geology rock avalanche deposits. ref name SI http cat.inist.fr ?aModele afficheN&cpsidt 1746803 CAT.INIST Pebble Creek Formation Retrieved on 2007 06 17 ref The two rock avalanches are not linked with the 2,350 BP eruption, although the post eruption avalanche may have its causes in the over steepened slopes produced by the explosive period of the eruption. ref name SI The rocks of the Pebble Creek Formation are the youngest known of the Mount Meager volcanic complex, and are made of dacite . ref name SI The formation includes a dacite lava lava flow , pyroclastic flow s, lahar s and fallout pumice . ref name SI References Reflist coord missing British Columbia Category Volcanology Category Sea to Sky Country Category Lillooet Country Category Garibaldi Volcanic Belt Category Stratigraphy of British Columbia Category Holocene volcanism Volcanology stub BritishColumbiaInterior geo stub ... more details
Unreferenced stub auto yes date December 2009 Image Mineraly.sk ryodacit.jpg right thumb A sample of rhyodacite from Slovakia Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite . It is the extrusive equivalent of granodiorite . Phenocrysts of sodium rich plagioclase , sanidine , quartz , and biotite or hornblende are typically set in an aphanitic to glassy light to intermediate colored matrix. Rhyodacite is a high silica rock and often exists as explosive pyroclastic volcanic deposits. Commons category Category Aphanitic rocks Category Volcanic rocks Category Volcanology Volcanology stub de Rhyodazit fr Rhyodacite pl Ryodacyt sk Ryodacit ... more details
Unreferenced date December 2009 Orphan date December 2009 Image Paliokastro.jpg thumb right The Acropolis Palaiokastro in Methana Image Paliokastro methana.jpg thumb right Acropolis of ancient Methana is located 1 km from the town of Megalochori Methana , Greece Megalochori in the volcanic peninsula of Methana . It was first built in the Mycenean civilization Mycenean times . It was rebuilt and destroyed later during the Roman Empire Roman and the Byzantine Empire Byzantine times. It was built from andesite and dacite rocks from the volcanic mountain nearby. The small acropolis is located on a small lava dome . Around the acropolis, Pausanias described the ancient market Agor and a sanctuary of Isis and Hermes . Remains of the ancient town Methana can be found around the Paliocastro and some Roman columns in front of the little St. Niclaus chapel. Category Ancient Greek buildings and structures Category Troizina area Greece geo stub ... more details
Infobox Australian Place type suburb name Taylor city Canberra state Australian Capital Territory image Taylor ACT.jpg lga Gungahlin est 1991 postcode 2913 pop propval near nw near n near ne near w near e Moncrieff, Australian Capital Territory Moncrieff near sw Casey, Australian Capital Territory Casey near se Ngunnawal, Australian Capital Territory Ngunnawal near s Ngunnawal, Australian Capital Territory Ngunnawal Taylor is a designated suburb in Gungahlin district Gungahlin , Canberra though the first land release is yet to be announced. The suburb is named after magazine publisher Florence Mary Taylor Florence Taylor OBE , who was editor of and writer for several Australian building industry journals including the influential Building magazine. The suburb is approximately 4 km from the Gungahlin Gungahlin Town Centre and 16 km from the centre of Canberra and bounded by Horse Park Drive. The suburb is located in north Gungahlin adjacent to the existing suburb of Ngunnawal, Australian Capital Territory Ngunnawal and the future suburbs of Casey, Australian Capital Territory Casey and Moncrieff, Australian Capital Territory Moncrieff . History Until 1991, the suburb Taylor was part of the former Gold Creek a 1,594 hectare rural property with the Gold Creek Homestead, Australian Capital Territory Gold Creek Homestead at its centre. ref Newman Chris 2004 , Gold Creek, Reflections of Canberra s Rural Heritage , Gold Creek Homestead Working Group. ref Geology The rocks in Taylor are from the late middle Silurian period. Hawkins volcanics green grey dacite and quartz andesite are in the west. The Canberra Formation is separated by a fault in the east side. It consists of slate y shale and mudstone , with north east trending bands of acid volcanics dacite and andesite . References reflist 1 refbegin See also Geology of the Australian Capital Territory Canberra geo stub coord 35 09 S 149 06 E region AU type city source GNS enwiki display title Category Suburbs of ... more details
Location map Australian Capital Territory label Williamsdale lat deg 35 lat min 34 lon deg 149 lon min 8 Williamsdale is a village on the New South Wales Australian Capital Territory border in Australia on the Monaro Highway . The postcode is 2620. Geology To the east of Williamsdale is the Williamsdale Volcanics. These are made up from blue green crystal tuff . The crystals are sized from 0.3 mm to 1 mm and are embedded in a fine matrix. Quartz crystals make up 25 , plagioclase 5 , alkali feldspar 10 , biotite 5 10 which is altered to chlorite , epidote and leucoxene . Middle Silurian Colinton Volcanics foliated dacite and tuff is under Williamsdale. A roughly north south band of these acid volcanics extends to the north along the Monaro Highway and then follows the Cooma road to Cottondale. South the volcanics also follow the Monaro Highway in a more complex band through Colinton past Michelago, New South Wales Michelago and at least as far south as Bredbo, New South Wales Bredbo . To the west of Williamsdale is an outcrop of Upper Silurian Laidlaw Volcanics dark grey rhyodacitic and dacitic crystal tuff. This extends to the west as far as Angle Crossing. This band extends to the north north west as far as Mount Stromlo . The outcrop finishes a couple of kilometres south, but it is also found to the east, with outcrop from Fernleigh, New South Wales Fernleigh in the north, via Burra, New South Wales Burra , and south to Michelago. On the west side of the Murrumbidgee River around Angle Crossing can be found the Bransby Beds or Goosoon Beds. These beds contain tuff and dacite with some sediments. They form a narrow band extending to the south as far as Cooma, New South Wales Cooma following on the east side of the Murrumbidgee River. See also Geology of the Australian Capital Territory External links http www.nswrail.net locations show.php?name NSW Williamsdale&line NSW bombala 0 Williamsdale Railway Siding Canberra geo stub coord 35 34 S 149 08 E region ... more details
Volcanic Belt Dacite 200,000 years ago Ember Ridge Garibaldi Volcanic Belt Andesite Pleistocene ... Northern Cordilleran Volcanic Province Miocene Mount Meager Garibaldi Volcanic Belt Dacite 2,350 years ... Volcanic Zone Andesite to Dacite Bolivia Nuevo Mundo volcano Chile class wikitable sortable Dome or volcano ... Volcanic Zone Dacite Pliocene Chait n Volcano Chait n Southern Volcanic Zone Rhyolite 2010 Corona ... Lascar Central Volcanic Zone Dacite 2007 Nevados de Chill n Volc n Nuevo Southern Volcanic Zone Dacite 1986 Sollipulli Southern Volcanic Zone Andesite to Dacite Taapaca Central Volcanic Zone Holocene ... more details
and consists of rhyolite or dacite . Dome dynamics Lava domes are Dynamics physics dynamic structures ... Volcanic Arc Dacite 2350 BP Mount Merapi Indonesia Sunda Arc Nea Kameni Greece Nevados de Chill n Volc n Nuevo Chile Southern Volcanic Zone Dacite 1986 Puy de D me mountain Puy de D me France Cha ne des Puys ca. 5760 BC Santiaguito Guatemala Central America Volcanic Arc Dacite 2009 Sollipulli Chile Southern Volcanic Zone Andesite to Dacite Soufri re Hills Montserrat Lesser Antilles 2009 Mount ... Iceland Hotspot Rhyolite Unnamed Japan Geology of Japan Japan Arc Dacite Miocene ref Yoshihiko Goto and Nobutaka Tsuchiya. Morphology and growth style of a Miocene submarine dacite lava dome at Atsumi ... more details
side. Volcanism in this sequence ended with the eruption of large rhyolite and dacite dome flow ... epiclastic volcarenite, rhyolite dacite block breccia from lava domes, polymict breccia, and a conglomerate of andesite, dacite rhyolite clasts, and andesitic tuff. The exposed succession consists ... more details
Infobox mountain name Nevado Anallajsi photo AnallajsiNevado.jpg photo caption The upper right part of the NASA Space Shuttle image shows the eroded volcanic complex Nevado Anallajsi. elevation m 5,750 elevation ref prominence location Bolivia range Andes coordinates coord 17 55 S 68 55 W type mountain topo type Stratovolcano age last eruption Unknown first ascent easiest route Nevado Anallajsi is a stratovolcano in Bolivia . The date of its last eruption is unknown, but its youngest lava flows appear to have erupted from a vent on the north flank of the mountain. The main composition of the volcano is Andesite andesitic and Dacite dacitic . It overlies a plateau which is composed of ignimbrite . See also List of volcanoes in Bolivia Sources Global Volcanism Program DEFAULTSORT Anallajsi Category Stratovolcanoes Category Subduction volcanoes Category Volcanoes of Bolivia Category Mountains of Bolivia Category Polygenetic volcanoes Category La Paz Department, Bolivia LaPazBO geo stub de Anallajsi es Nevado Anallajsi fr Nevado Anallajsi ka os hu Nevado Anallajsi pl Nevado Anallajsi pt Nevado Anallajsi qu Anallaqsi ... more details
Infobox mountain name Macizo de Larancagua photo photo caption elevation m 5520 elevation ref prominence location Bolivia range Andes coordinates coord 18 15 0 S 63 32 0 W type mountain region BO display inline,title topo type Stratovolcano age last eruption first ascent easiest route Macizo de Larancagua is a stratovolcano in Bolivia . It lies west of Turco municipio Turco and is composed of andesite and dacite . The date of its last eruptive episode is unclear, but some authors have assigned it as Holocene . See also List of volcanoes in Bolivia Sources Global Volcanism Program DEFAULTSORT Macizo De Larancagua Category Stratovolcanoes Category Subduction volcanoes Category Volcanoes of Bolivia Category Mountains of Bolivia Category Polygenetic volcanoes Category Oruro Department Oruro geo stub fr Macizo de Larancagua ka os hu Macizo de Larancagua pl Macizo de Larancagua pt Macizo de Larancagua qu Laranqawa urqu ... more details
Infobox mountain name Mount Nansen photo photo caption elevation m 1827 elevation ref prominence m 532 prominence ref location Yukon , Canada range coordinates coord 62 06 22.3 N 137 18 10.1 W type mountain region CA display inline,title topo National Topographic System NTS 115J 03 type Stratovolcano age Late Cretaceous volcanic arc belt last eruption first ascent easiest route Mount Nansen is a deeply eroded Late Cretaceous stratovolcano located 53 kilometers west of Carmacks, Yukon Carmacks and 10 kilometers west of Victoria Mountain in the central Yukon , Canada . It consists of rhyolite , dacite , andesite flows, breccia s and tuff . Mount Nansen was formed when the ancient Kula Plate was subduction subducting under North America during the Late Cretaceous period. See also Portal Volcanism of Canada List of volcanoes in Canada Volcanism in Canada External links http www.bivouac.com MtnPg.asp?MtnId 3573 Mount Nansen in the Canadian Mountain Encyclopedia Category Volcanoes of Yukon Nansen, Mount Category Mountains of Yukon Nansen, Mount Category Stratovolcanoes Nansen, Mount Category Subduction volcanoes Nansen, Mount Yukon geo stub ... more details
Infobox mountain name Curacoa photo elevation convert 33 m ft ref name gvp cite gvp vnum 0403 102 title Curacoa accessdate 2010 02 27 ref prominence listing List of volcanoes in Tonga location Tonga Islands range coordinates coord 15.62 S 173.67 W type mountain topo type Submarine volcano age volcanic Arc Belt last eruption 1979 first ascent easiest route caption Curacoa is a submarine volcano located south of Curacoa Reef in northern Tonga . Eruptions were observed in 1973 and 1979, from two separate vents. The 1973 eruption produced a large pumice raft raft of dacite dacitic pumice . That eruption had a Volcanic Explosivity Index VEI of 3. See also List of volcanoes in Tonga References references Category Volcanoes of Tonga Category Submarine volcanoes Category Active volcanoes Tonga geo stub ca Curacoa nl Curacoa vulkaan sk Curacoa sopka ... more details
seealso Palisades Sill Image Palisades Sill sign near Cimarron, NM Picture 2023.jpg 200px right thumb font size 2 Description of Palisades Sill south of Cimarron, New Mexico Cimarron , New Mexico font size 2 Image Palisades Sill in NM Picture 2021.jpg 200px right thumb font size 2 Cliffs of Palisades Sill font size 2 File Palisades sill, NM.jpg thumb 200px left font size 2 Palisades Sill of Cimarron River Canyon font size 2 The Palisades Sill is a fine grained porphyritic dacite Sill geology sill which form spectacular cliffs and palisades in the Cimarron River canyon between Eagle Nest, New Mexico Eagle Nest and Cimarron, New Mexico Cimarron in northern New Mexico . It can be seen in the eastern part of Cimarron Canyon State Park ref cite web url http geoinfo.nmt.edu tour state cimarron home.html title NMBGMR Geologic Tour Cimarron Canyon State Park publisher New Mexico Bureau of Geology and Mineral Resources accessdate 2009 03 29 ref References reflist coord missing New Mexico Category Geology of New Mexico Category Sills br NewMexico geo stub he ... more details
Roca Consag Consag Rock is a granitic or more precisely, dacite dacitic outcrop located in the northern Gulf of California about 17 miles ENE of the town of San Felipe, Baja California San Felipe . The outcrop stands about 286 feet above the sea, and is named for the Jesuit missionary Ferdinand Kon ak who was active in the early exploration and missionary work in Baja California . The ruins of an abandoned lighthouse can be seen on the west side of the outcrop. ref http www.mexfish.com rkyp rkyp af000823 af000823.htm Beyond Roca Consag A Different Trip To Puerto Pe asco, mexfish.com, photo ref The waters in the vicinity of the Roca Consag are a popular fishing area and also favored for spotting whales and porpoises. References reflist http books.google.com books?id mP0CklZvMMEC&pg PA115&lpg PA115&dq Roca Consag&source bl&ots ZMLLfaezO6&sig 4JL6X7AowJl5mSeCWF1WCsLHcw4&hl en&ei uUXPS8i7DJK2swP4lfiuDg&sa X&oi book result&ct result&resnum 7&ved 0CBMQ6AEwBjgU v onepage&q Roca 20Consag&f false Best Places Baja, by Lori Makabe, 2002, p.115 Category Geology of Mexico regional geology stub ... more details
File WheelerGACO.jpg thumb The Fish Canyon Eruption ignimbrite The Fish Canyon Eruption was the largest known volcanic eruption on Earth, estimated at 5,000 cubic kilometers. ref cite web last Ort first Michael title Largest explosive eruptions url http staff.aist.go.jp s takarada CEV newsletter lagarita.html accessdate 14 August 2010 ref The eruption was centered at La Garita Caldera in southwest Colorado . The tuff can be assured to belong to one eruption due to its high chemical consistency SiO sub 2 sub bulk 67.5 68.5 dacite , matrix 75 76 rhyolite and consistent phenocryst content 35 50 and composition plagioclase , sanidine , quartz , biotite , hornblende , sphene , apatite , zircon , Fe Ti oxide s are the primary phenocrysts . This tuff and eruption is part of the larger San Juan volcanic field and Mid Tertiary ignimbrite flare up . References references See also Tuff Ignimbrite Mid Tertiary ignimbrite flare up World s largest eruptions Category Flood basalts ... more details
dacite at the east base of Mount Boucherie Mount Boucherie is composed primarily of rhyolite and andesite .... The more prominent black and dark gray east and north east face is dacite . ref name okgeology ... stages of Mount Boucherie s volcanic period, as evidenced by the fact that the dacite columns intersect ... of folded volcanic flows of dacite. ref name okgeology How to insert nicely ? into the article ... Boucherie east face.jpg Another view of the east face, with a broken column of crystalline dacite in the foreground ... more details
period. Along the hill tops the rock is from the Hawkins Volcanics, with mostly dacite in the south, and andesite in the north. The north east of the suburb has dacite from the Canberra Formation. The south east has a green grey porphyry geology porphyry with a dacite like composition, and visible ... more details
is a lava dome composed almost entirely of dacite dacitic lava flows which emerged from several ... sequence s. Likewise, because of the high viscosity of the dacite, it is likely that the mountain ... material are unique to the mountain, which otherwise is uniformly composed of silicic dacite ... more details
Infobox Australian Place type suburb name Hall state Australian Capital Territory city Canberra image Hall IBMap MJC.png caption lga postcode 2618 est 1882 propval 885,000 2008 ref name allhomesY cite web url http www.allhomes.com.au ah ah0095?divid 10042 title Suburb Information publisher Allhomes accessdate 1 June 2009 ref pop 338 2006 census ref name Census2006Y Census 2006 AUS id SSC81231 name Hall State Suburb accessdate 1 June 2009 quick on ref ACTgov Ginninderra electorate Ginninderra fedgov Division of Fraser Fraser near nw Wallaroo, New South Wales near n Springrange, New South Wales near ne near e near w near sw near s Kinlyside, Australian Capital Territory near se Hall is a small town in the north of the Australian Capital Territory ACT , Australia . It was founded in 1882, named after the first landholder in the area, Henry Hall farmer Henry Hall . In 1911 Hall was included within the boundary of the land allocated for the Australian Capital Territory, close to the north western corner, near the New South Wales border. Although considered a village, similar to Tharwa , in practical terms Hall might now be considered an outer suburb of Australia s capital Canberra . In 1954 the main street of Hall which had been part of the state highway system since 1935 was named the Barton Highway . In 1980 the alignment of the highway was shifted to the south as part of a dual carriage upgrade, bypassing Hall completely. Some features of note within Hall village are the equestrian park , playing fields, showground, and former Hall Primary School , along with a small shopping centre and three historic churches. The showground area plays host to the Hall Markets , a popular monthly charity market showcasing hand produced goods. Geology In the Hall area the rocks are all Silurian age volcanic rocks. Green grey and purple quartz andesite and dacite from the Hawkins Volcanics are under the village and extending up the Halls Creek valley. Green grey dacite and quartz andes ... more details
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