Sample: 53-B-13
| Sample ID: | 53-B-13 [1] | ||||||||||||
| Station ID: | 53-B-13 | ||||||||||||
| AT Num: | |||||||||||||
| Volcano: | Makushin | ||||||||||||
| Possible source: | |||||||||||||
| Eruption: | |||||||||||||
| Collector: | Barnett, H. F. J. | ||||||||||||
| Date sampled: | 1953-01-01 | ||||||||||||
| Sample type 1: | Countryrock | ||||||||||||
| Color: | |||||||||||||
| Final unit: | |||||||||||||
| Text Description: | Granogabbro occurring one-third mile from the Beaver pluton contact on the east side of Final Bay. The texture is hypidiomorphic and the groundmass is myrmekitic. Felsic minerals compose 80-85 percent of the rock: 7-10 percent quartz, 15-25 percent alkali feldspar partially altered to kaolin (2-3 percent), and 50-58 percent plagioclase partly altered to sericite (about 5 percent) and epidote-clinozoisite (about 1 percent). The plagioclase composition, by extinction angle, is A62 [mean of 28 crystals, standard deviation is 10 percent An, average amount of zoning per individual plagioclase crystal is 2 percent An per crystal], by index oils, is An54. Mafic minerals compose 15-20 percent: 10-13 percent uralitic hornblende (probably 85 percent of this after pyroxene, 15 percent after biotite) partly altered to penninite (0.5-1.5 percent). 0.5-1.5 percent sphene partly altered to leucoxene (0.1 percent), 4-6 percent magnetite, and <1 percent apatite. The discrepancy in plagioclase composition is probably due to sodium in the alkalic feldspar, and potassium in the plagioclase (?). | ||||||||||||
| Sample Location: |
       623 1312 70 9 117 16 384 106 41 24 52 1153 69 Great Sitkin Spurr Akutan Aniakchak Atka volcanic complex Augustine Cleveland Dutton Edgecumbe Fisher Gareloi Griggs Iliamna Isanotski Kanaga Katmai Little Sitkin Mageik Makushin Martin Novarupta Pavlof Redoubt Semisopochnoi Shishaldin Snowy 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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References Cited
[1] Geology of Unalaska Island and adjacent insular shelf, Aleutian Islands, Alaska, 1961
Drewes, Harald, Fraser, G. D., Snyder, G. L., and Barnett, H. F. Jr., 1961, Geology of Unalaska Island and adjacent insular shelf, Aleutian Islands, Alaska: in Investigations of Alaskan volcanoes, U.S. Geological Survey Bulletin 1028-S, p. 583-676, 3 sheets, scale 2 at 1:250,000 and 1 unknown.
full-text PDF 3.3 MB
plate 75 PDF 6.7 MB
plate 76 PDF 113 KB
plate 77 PDF 250 KB
table 1 PDF 326 KB