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Sample info : 46AC116
Sample ID:46AC116
Station ID:46AC116
Latitude:51.9242
Longitude:-177.1623
Datum:NAD83
Date Sampled:1946-01-01
Sample Type 1:Lava
Field Lithology:Basalt
Text Description:
1906 lava? Medium dark-gray (N4) hypersthene basalt, porphyritic, with vesicular structure. Plagioclase phenocrysts range in size from 0.1 to 3 mm. The median composition is An[58?], but one rounded grain of anorthite (average index 1.58) was seen as presumed to be a xenocryst. The saltie crystals have nY 1.70, suggesting a composition about Ca50Mg30Fe20. The hypersthene prisms, which range in size from 0.1 to 1 mm, have nZ 1.70 corresponding to En73Fs27. The optic axial angle of the olivine seen in thin section was the same as that in 46AC97, suggesting that here also its composition is about Fo72Fa28. Olivine is rare, and no olivine was found in the crushed fragments. The groundmass consists of plagioclase laths and augite rods in brown glass with an index of 1.50 plus/minus 0.005. The accessory minerals are magnetite or ilmenite, from 1 to 0.1 mm, and apatite, in stubby prisms, 0.05 mm long, clear where included in hypersthene or salite but with a slightly pseudodichroic rim elsewhere.

References:
Magmatic differentiation in Tertiary and Quaternary volcanic rocks from Adak and Kanaga Islands, Aleutian Islands, Alaska

Geochem Data:
StationIDlatitudelongitudeGeologistDateVisitedVolcanoLocationDescriptionTextDescriptionSample IDSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-majorsREF majorsMETH majorsFe2O3/Fe203T origFeO/FeOT origVolatiles csvMETH volatilesCsRbBaSrLaCePrNdSmEuGdTbDyHoErTmYbLuYZrNbHfTaPbThUScVCrFeCoNiCuZnGaMoAsNaKRef trace1METH trace1RbBaSrLaCeNdSmEuGdDyErYbLuYZrNbPbThUScTiVCrNiCuZnGaRef trace2METH trace2Light csvHalogen csvother major csvother lile csvother ree csvother hfse csvother hpe csvother tm csvother misc csv
46AC11651.9242-177.1623Unknown, Unknown1946-01-01Kanaga6,400 feet south 49.5 degrees west from the center of the crater of Kanaga volcano.1906 lava? Medium dark-gray (N4) hypersthene basalt, porphyritic, with vesicular structure. Plagioclase phenocrysts range in size from 0.1 to 3 mm. The median composition is An[58?], but one rounded grain of anorthite (average index 1.58) was seen as presumed to be a xenocryst. The saltie crystals have nY 1.70, suggesting a composition about Ca50Mg30Fe20. The hypersthene prisms, which range in size from 0.1 to 1 mm, have nZ 1.70 corresponding to En73Fs27. The optic axial angle of the olivine seen in thin section was the same as that in 46AC97, suggesting that here also its composition is about Fo72Fa28. Olivine is rare, and no olivine was found in the crushed fragments. The groundmass consists of plagioclase laths and augite rods in brown glass with an index of 1.50 plus/minus 0.005. The accessory minerals are magnetite or ilmenite, from 1 to 0.1 mm, and apatite, in stubby prisms, 0.05 mm long, clear where included in hypersthene or salite but with a slightly pseudodichroic rim elsewhere.46AC116 55.478856261567 0.83922635079625 16.834480965377 8.6042540823317 0.16984342813734 3.7765185785831 8.6320424653329 3.4967764616511 1.6384895420308 0.27974211693209 100.51085NN4.074.95H2OP=0.21; H2OM=0.04NN


Sample Location

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