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SAMPLE INFO : specimen 2
Sample ID:specimen 2
Station ID:specimen 2
Latitude:51.83
Longitude:-176.42
Datum:NAD83
Date Sampled:1952-01-01
Sample Type 1:Countryrock
Sample Type 2:Plutonic
Text Description:
Granodiorite. The rocks 1,500 yards south of Blind Cove have a color index near 10 and are more felsic than most of the granodiorite. These rocks contain a few dark rounded fine-grained patches as much as severa1 centimeters in diameter that appear to be recrystallized and partly assimilated wall rock. A marked preferred orientation of biotite and hornblende was noted in some outcrops. A peculiar texture, suggestive of mortar structure, is visible in thin section. This texture consists of large (3 mm) zoned plagioclase crystals with narrow interstitial bands of granular quartz (0.4 mm) and orthoclase (0.2 mm). The quartz and orthoclase crystallized later than the plagioclase; possibly magma motion helped to produce the texture. A modal analysis of one of these rocks (specimen no. 2) gives the following volume percentages: zoned andesine-oligoclase, 57; orthoclase, 11; quartz, 21; biotite, 4.7; hornblende, 4.5 (some of these in blocky crystals with a maximum diameter of 8 mm); opaque oxides, 0.9; chlorite (mostly after biotite), 0.8; sphene, apatite, and zircon, total, 0.1.

References:
Geology of southern Adak Island and Kagalaska Island, 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
specimen 251.83-176.42Unknown, Unknown1952-01-01 Kagalaska Strait, northeast Adak IslandGranodiorite. The rocks 1,500 yards south of Blind Cove have a color index near 10 and are more felsic than most of the granodiorite. These rocks contain a few dark rounded fine-grained patches as much as severa1 centimeters in diameter that appear to be recrystallized and partly assimilated wall rock. A marked preferred orientation of biotite and hornblende was noted in some outcrops. A peculiar texture, suggestive of mortar structure, is visible in thin section. This texture consists of large (3 mm) zoned plagioclase crystals with narrow interstitial bands of granular quartz (0.4 mm) and orthoclase (0.2 mm). The quartz and orthoclase crystallized later than the plagioclase; possibly magma motion helped to produce the texture. A modal analysis of one of these rocks (specimen no. 2) gives the following volume percentages: zoned andesine-oligoclase, 57; orthoclase, 11; quartz, 21; biotite, 4.7; hornblende, 4.5 (some of these in blocky crystals with a maximum diameter of 8 mm); opaque oxides, 0.9; chlorite (mostly after biotite), 0.8; sphene, apatite, and zircon, total, 0.1.specimen 2CountryrockEnclave/InclusionWhole-rock 63.3 0.46 17.24 4.04 0.08 2.48 5.4 4.12 2.15 0.18 100.05356NN1.92.33H2OM=0.04; H2OP=0.45; CO2=0; Cl=0.02; F=0.04NN 28.5 776 15.7 units are percent 1.78745XRF: Rb, Sr, Ni; NN: K;
specimen 251.83-176.42Unknown, Unknown1952-01-01 Kagalaska Strait, northeast Adak IslandGranodiorite. The rocks 1,500 yards south of Blind Cove have a color index near 10 and are more felsic than most of the granodiorite. These rocks contain a few dark rounded fine-grained patches as much as severa1 centimeters in diameter that appear to be recrystallized and partly assimilated wall rock. A marked preferred orientation of biotite and hornblende was noted in some outcrops. A peculiar texture, suggestive of mortar structure, is visible in thin section. This texture consists of large (3 mm) zoned plagioclase crystals with narrow interstitial bands of granular quartz (0.4 mm) and orthoclase (0.2 mm). The quartz and orthoclase crystallized later than the plagioclase; possibly magma motion helped to produce the texture. A modal analysis of one of these rocks (specimen no. 2) gives the following volume percentages: zoned andesine-oligoclase, 57; orthoclase, 11; quartz, 21; biotite, 4.7; hornblende, 4.5 (some of these in blocky crystals with a maximum diameter of 8 mm); opaque oxides, 0.9; chlorite (mostly after biotite), 0.8; sphene, apatite, and zircon, total, 0.1.specimen 2CountryrockEnclave/InclusionWhole-rock H2OM=0.04; H2OP=0.45; CO2=0; Cl=0.02; F=0.04NN 356

SAMPLE LOCATION

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