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SAMPLE INFO : 46AC174
Sample ID:46AC174
Station ID:46AC174
Latitude:51.937
Longitude:-176.741
Datum:NAD83
Date Sampled:1946-01-01
Sample Type 1:Lava
Sample Type 2:Dome
Field Lithology:Basalt
Text Description:
Medium-gray (N5) hypersthene basalt, with seriate, intergranular texture. The most conspicuous crystals are of plagioclase, up to 3 mm in size, with a median composition ranging from An64 to An49 in different specimens. The sparse salite as much as 0.5 mm in size, has nZ 1.716 and nX 1.688. This suggests a composition of about En72Fs28. Olivine is very rare, and is characterized by a heavy reaction border and segregations of opaque material, apparently magnetite, along cleavage planes. Hornblende, which has a heavy resorption border of clinopyroxene, is very rare. Similar borders are also found on some grains of olivine and hypersthene. Magnetite and apatite are common accessories; the latter may be clear, where enclosed in hypersthene for example, or pseudodichronic, where exposed to reaction with the last part of the magma to crystallize. The groundmass consists of plagioclase laths, clinopyroxene granules, and interstitial orthoclase (?). Tridymite lines fractures and cavities, and is, in part, pseudomorphous after cristobalite.

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

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedVolcanoLocation DescriptionText DescriptionSample 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
46AC174 51.937 -176.741 Unknown, Unknown 1946-01-01 MoffettFrom one of the late domes of Mt. Moffett (Hill 1981) about 11,000 feet south 5 degrees east of the summit of Mt. Moffett.Medium-gray (N5) hypersthene basalt, with seriate, intergranular texture. The most conspicuous crystals are of plagioclase, up to 3 mm in size, with a median composition ranging from An64 to An49 in different specimens. The sparse salite as much as 0.5 mm in size, has nZ 1.716 and nX 1.688. This suggests a composition of about En72Fs28. Olivine is very rare, and is characterized by a heavy reaction border and segregations of opaque material, apparently magnetite, along cleavage planes. Hornblende, which has a heavy resorption border of clinopyroxene, is very rare. Similar borders are also found on some grains of olivine and hypersthene. Magnetite and apatite are common accessories; the latter may be clear, where enclosed in hypersthene for example, or pseudodichronic, where exposed to reaction with the last part of the magma to crystallize. The groundmass consists of plagioclase laths, clinopyroxene granules, and interstitial orthoclase (?). Tridymite lines fractures and cavities, and is, in part, pseudomorphous after cristobalite.46AC174 54.970543859962 0.84539100773285 17.149360442581 7.932893586427 0.1509626799523 3.9250296787597 9.5911622663025 3.5727834255376 1.3586641195707 0.26166864525064 99.711085NN3.474.76H2OP=0.13; H2OM=0.11NN

SAMPLE LOCATION

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