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SAMPLE INFO : 54-Sn-284B
Sample ID:54-Sn-284B
Station ID:54-Sn-284B
Latitude:53.88707
Longitude:-166.93202
Datum:NAD83
Date Sampled:1954-01-01
Sample Type 1:Countryrock
Sample Type 2:Plutonic
Field Lithology:Granitic
Text Description:
Granite, the matrix of a "plum pudding" rock, from a beach boulder near the head of the north arm of Skan Bay. The texture is hypidiomorphic-granular; the original rock contains many inclusions but this analysis is of matrix only. Felsic minerals compose 93-97 percent of the rock: 10-20 percent quartz, 50-70 percent alkalic feldspar heavily altered to kaolin (10-20 percent), and 15-25 percent plagioclase partly altered to epidote (0.1-0.5 percent), sericite (0.1-1 percent), and kaolin (lumped with above). The plagioclase composition, by extinction angle, is A18 [mean of 5 crystals, standard deviation is 9 percent An, average amount of zoning per individual plagioclase crystal is 0 Percent An per crystal]. Mafic minerals compose 3-7 percent: 2-3 percent hornblende and 0.1-0.5 percent is biotite both partly altered to epidote (0.1-1 percent) and penninite (0.1-0.3 percent), 1-1.5 percent is magnetite, 0.1-1 percent is sphene slightly altered to lucoxene, 0.1-0.5 percent is rutile occurring as stubby yellow rods in sphene, and 0.1-0.3 percent is penninite (interstitial). Comparison of the mode and norm for this rock indicates that the alkalic feldspar contains large quantities of both orthoclase and albite.

References:
Geology of Unalaska Island and adjacent insular shelf, Aleutian Islands, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDSample Type 1Sample Type 2Final UnitMaterialSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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
54-Sn-284B53.88707-166.93202Snyder, G. L.1954-01-01 MakushinGranodiorite and related rocks from 1 mi N of 3600 Mtn. From a beach boulder near the head of the north arm of Skan Bay.Granite, the matrix of a "plum pudding" rock, from a beach boulder near the head of the north arm of Skan Bay. The texture is hypidiomorphic-granular; the original rock contains many inclusions but this analysis is of matrix only. Felsic minerals compose 93-97 percent of the rock: 10-20 percent quartz, 50-70 percent alkalic feldspar heavily altered to kaolin (10-20 percent), and 15-25 percent plagioclase partly altered to epidote (0.1-0.5 percent), sericite (0.1-1 percent), and kaolin (lumped with above). The plagioclase composition, by extinction angle, is A18 [mean of 5 crystals, standard deviation is 9 percent An, average amount of zoning per individual plagioclase crystal is 0 Percent An per crystal]. Mafic minerals compose 3-7 percent: 2-3 percent hornblende and 0.1-0.5 percent is biotite both partly altered to epidote (0.1-1 percent) and penninite (0.1-0.3 percent), 1-1.5 percent is magnetite, 0.1-1 percent is sphene slightly altered to lucoxene, 0.1-0.5 percent is rutile occurring as stubby yellow rods in sphene, and 0.1-0.3 percent is penninite (interstitial). Comparison of the mode and norm for this rock indicates that the alkalic feldspar contains large quantities of both orthoclase and albite.54-Sn-284BCountryrockEnclave/InclusionWhole-rock 66 0.73 15.8 3.1 0.06 1.1 2.1 4.7 5.4 0.17Total not given in table. 100.74315RAPIDA1.71.6H2OM=0.05; H2OP=0.61; CO2=0.05; Cl=0.13; F=0.09RAPIDA

SAMPLE LOCATION

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