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SAMPLE INFO : specimen 5
Sample ID:specimen 5
Station ID:specimen 5
Latitude:51.72
Longitude:-176.83
Datum:NAD83
Date Sampled:1952-01-01
Sample Type 1:Countryrock
Sample Type 2:Plutonic
 Text Description:
Near the contact with Finger Bay volcanics, a dark-gray porphyritic feldspathic granodiorite, color index commonly 10 to 15, is a conspicuous and characteristic rock. Analyzed specimen no. 5, from the contact at the north end of Bay of Waterfalls, is one of these. About one-third of the rock is large (+/- 7 mm) crystals of cloudy, dark-gray zoned plagioclase that give it the appearance of anorthosite. A preferred orientation of these crystals was observed in several outcrops. The large plagioclase crystals are set in a fine, subhedral-granular matrix. The mode is: plagioclase, 65.5 percent; alkali feldspar and orthoclase, 13 percent; quartz, 8.2 percent; hornblende, 7.6 percent; clinopyroxene, 1.6 percent; opaque oxide, 3.0 percent; biotite, 0.4 percent; chlorite, 0.3 percent; apatite, 0.3 percent, and sphene, 0.1 percent.

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 551.72-176.83Unknown, Unknown1952-01-01 Bay of Waterfalls, southwest Adak IslandNear the contact with Finger Bay volcanics, a dark-gray porphyritic feldspathic granodiorite, color index commonly 10 to 15, is a conspicuous and characteristic rock. Analyzed specimen no. 5, from the contact at the north end of Bay of Waterfalls, is one of these. About one-third of the rock is large (+/- 7 mm) crystals of cloudy, dark-gray zoned plagioclase that give it the appearance of anorthosite. A preferred orientation of these crystals was observed in several outcrops. The large plagioclase crystals are set in a fine, subhedral-granular matrix. The mode is: plagioclase, 65.5 percent; alkali feldspar and orthoclase, 13 percent; quartz, 8.2 percent; hornblende, 7.6 percent; clinopyroxene, 1.6 percent; opaque oxide, 3.0 percent; biotite, 0.4 percent; chlorite, 0.3 percent; apatite, 0.3 percent, and sphene, 0.1 percent.specimen 5CountryrockEnclave/InclusionWhole-rock 58.44 0.92 18.79 5.62 0.12 1.81 6.17 4.57 2.53 0.46 100.11356NN3.232.7H2OM=0.02; H2OP=0.38; CO2=0.02; Cl=0.07; F=0.07NN 40.7 555 5.6 units are percent 2.09745XRF: Rb, Sr, Ni; NN: K;
specimen 551.72-176.83Unknown, Unknown1952-01-01 Bay of Waterfalls, southwest Adak IslandNear the contact with Finger Bay volcanics, a dark-gray porphyritic feldspathic granodiorite, color index commonly 10 to 15, is a conspicuous and characteristic rock. Analyzed specimen no. 5, from the contact at the north end of Bay of Waterfalls, is one of these. About one-third of the rock is large (+/- 7 mm) crystals of cloudy, dark-gray zoned plagioclase that give it the appearance of anorthosite. A preferred orientation of these crystals was observed in several outcrops. The large plagioclase crystals are set in a fine, subhedral-granular matrix. The mode is: plagioclase, 65.5 percent; alkali feldspar and orthoclase, 13 percent; quartz, 8.2 percent; hornblende, 7.6 percent; clinopyroxene, 1.6 percent; opaque oxide, 3.0 percent; biotite, 0.4 percent; chlorite, 0.3 percent; apatite, 0.3 percent, and sphene, 0.1 percent.specimen 5CountryrockEnclave/InclusionWhole-rock H2OM=0.02; H2OP=0.38; CO2=0.02; Cl=0.07; F=0.07NN 356

SAMPLE LOCATION

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