Sample: 46AC130
| Sample ID: | 46AC130 [1] | ||||||||||||
| Station ID: | 46AC130 | ||||||||||||
| AT Num: | |||||||||||||
| Volcano: | Ancient Mount Kanaton | ||||||||||||
| Possible source: | |||||||||||||
| Eruption: | |||||||||||||
| Collector: | Unknown, Unknown | ||||||||||||
| Date sampled: | 1946-01-01 | ||||||||||||
| Sample type 1: | Tuff | ||||||||||||
| Color: | yellowish-gray | ||||||||||||
| Final unit: | |||||||||||||
| Text Description: | Andesite tuff, probably representing caldera-forming eruption. From a layer of yellowish-gray (5Y8/1) pumice, 1 to 2 feet thick, composed of fragments of pumice up to 0.25 inch across; during shipment, most of the coarser material was crushed, so that after shipment only about 5% of the material was coarser than 10 mesh. Of the coarser material, about half was made up of fragments of accidental and accessory rocks, the rest of essential and cognate material, largely pumice and cognate crystalline rocks. Of the material finer than 10 mesh, about 3% of the total sample was thought to be accidental and accessory material, divided about as follows: 30% plagioclase, 30% rock and glass, 20% pyroxene (augite and hypersthene), 10% magnetite or ilmenite, and 10% basaltic hornblende. Essential and cognate material makes up about 92% of the total; it includes the 81% of glass, the 1% of magnetite, the 1% of green hornblende, and the 9% of plagioclase. The chemical analysis was made on the material finer than 10 mesh; it is probable that the elimination from analyzed material of the accidental and accessory material could not have differed very greatly from that of the essential material. The essential material of the eruption is a clear, pumiceous glass, with index ranging from 1.495 to 1.505, containing phenocrysts of plagioclase, green hornblende, magnetite, and apatite. The plagioclase is zoned, and has a mean composition of An[53?]. The hornblende is clear, with a slight development of magnetite along the cleavages of a few grains. The pleochroism formula is: Z= olive-green, Y= yellowish-green, X= greenish-yellow. The extinction angle on (010) is 14 degrees. The nZ is 1.676, nX is 1.653. The magnetite or ilmenite is in equant grains, about 0.2 mm in maximum width. Apatite is in clear, stubby prisms, with sharp prismatic terminations. It may be noted that the index of the glass is rather lower than that to be expected from the diagrams of George (1924). | ||||||||||||
| Sample Location: |
       80 133 111 120 97 Akutan Aniakchak Atka volcanic complex Augustine Cleveland Dutton Edgecumbe Fisher Gareloi Great Sitkin Griggs Iliamna Isanotski Kanaga Katmai Little Sitkin Mageik Makushin Martin Novarupta Pavlof Redoubt Semisopochnoi Shishaldin Snowy Spurr Takawangha Tanaga Trident Ugashik-Peulik Ukinrek Maars Veniaminof Westdahl Wrangell Adagdak Addington volcanic field Alagogshak Amak Amchixtam Chaxsxii Amukta Andrew Bay volcano Basalt of Gertrude Creek Behm Canal-Rudyerd Bay Black Peak Bobrof Bogoslof Buldir Buzzard Creek Camille Cone Capital Carlisle Chagulak Chiginagak Churchill, Mt Cone 3110 Cone 3601 Dana Davidof Denison Devils Desk Double Glacier Douglas Drum Duncan Canal Emmons Lake Volcanic Center Espenberg Folsoms Bluff Fourpeaked Frosty Gas Rocks, the Gilbert Gordon Gosling Cone Hayes Herbert Imuruk Lake Volc Field Ingakslugwat Hills Ingenstrem Depression Volcanic Field Ingrisarak Mtn Iron Trig cone Iskut-Unuk River cones Jarvis Jumbo Dome Kagamil Kaguyak Kasatochi Kejulik Kialagvik Kiska Klawasi Group Knob 1000 Kochilagok Hill Koniuji Kookooligit Mountains Koyuk-Buckland volcanics Kukak Kupreanof Lone basalt Maclaren River volcanic field Moffett Monogenetic QT vents of WWVF Morzhovoi Nelson Island Nunivak Island Nushkolik Mountain volcanic field Okmok Pavlof Sister Prindle Volcano Rainbow River cone Recheshnoi Roundtop Sanford Seguam Segula Sergief Skookum Creek St. George volcanic field St. Michael St. Paul Island Steller Stepovak Bay 1 Stepovak Bay 2 Stepovak Bay 3 Stepovak Bay 4 Suemez Island Table Top Mtn Tanada Peak Tanax̂ Angunax̂ Tlevak Strait Togiak volcanics Uliaga Ungulungwak Hill-Ingrichuak Hill Unnamed (near Ukinrek Maars) Vsevidof Western Cones Wide Bay cone Yantarni Yunaska Legend ✕
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