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SAMPLE INFO : 54-D-100
Sample ID:54-D-100
Station ID:54-D-100
Latitude:53.88707
Longitude:-166.93202
Datum:NAD83
Date Sampled:1954-01-01
Sample Type 1:Countryrock
Sample Type 2:Plutonic
Text Description:
Granodiorite from the Captains pluton 1 mile southwest of the head of Captains Bay. The texture is hypidiomorphic-granular to porphyritic. Felsic minerals compose 75-85 percent of the rock: 10-15 percent quartz, 13-17 percent orthoclase partly altered to kaolin (2-4 percent), and 50-55 percent plagioclase partially altered to sericite (0.5-1.5 percent) and clinozoisite (<0.01 percent). The plagioclase composition, by extinction angle, is An48 [mean of 24 crystals, standard deviation is 14 percent An, average amount of zoning per individual plagioclase crystal is 16 percent An per crystal], by index oils, is An44. Mafic minerals compose 15-25 percent: 1 percent pyroxene (all as small inclusions in one large plagioclase crystal), 12-15 percent hornblende (50 percent of this is massive and poikilitic with magnetite, 50 percent of this is uralitic fibers), 3-5 percent biotite partially altered to penninite (1-2 percent) and ilmenite and sphene (0.5-1.5 percent) which in turn are altered to leucoxene (<1 percent), 2.4 percent magnetite, and <1 percent apatite (in feldspar).

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-D-10053.88707-166.93202Drewes, Harald1954-01-01 MakushinGranodiorite and related rocks from 1 mi SW of head of Captains BayGranodiorite from the Captains pluton 1 mile southwest of the head of Captains Bay. The texture is hypidiomorphic-granular to porphyritic. Felsic minerals compose 75-85 percent of the rock: 10-15 percent quartz, 13-17 percent orthoclase partly altered to kaolin (2-4 percent), and 50-55 percent plagioclase partially altered to sericite (0.5-1.5 percent) and clinozoisite (<0.01 percent). The plagioclase composition, by extinction angle, is An48 [mean of 24 crystals, standard deviation is 14 percent An, average amount of zoning per individual plagioclase crystal is 16 percent An per crystal], by index oils, is An44. Mafic minerals compose 15-25 percent: 1 percent pyroxene (all as small inclusions in one large plagioclase crystal), 12-15 percent hornblende (50 percent of this is massive and poikilitic with magnetite, 50 percent of this is uralitic fibers), 3-5 percent biotite partially altered to penninite (1-2 percent) and ilmenite and sphene (0.5-1.5 percent) which in turn are altered to leucoxene (<1 percent), 2.4 percent magnetite, and <1 percent apatite (in feldspar).54-D-100CountryrockEnclave/InclusionWhole-rock 61 0.9 15.8 5.9 0.1 3.4 5.4 3.6 2.6 0.22Total not given in table. 100.1315RAPIDA23.9H2OM=0.08; H2OP=1; CO2=0.05RAPIDA units are percent 0.08units are percent 0.1 units are percent 0 units are percent 0units are percent 0.02 units are percent 0 units are percent 0.004 0.02units are percent 0.01 0.001units are percent 0.002units are percent 0.01 units are percent 0.002units are percent 0 315NN

SAMPLE LOCATION

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