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SAMPLE INFO : SG05-10
Sample ID:SG05-10
Station ID:SG05-10
Latitude:56.573355924287
Longitude:-169.49659574817
Datum:NAD83
Date Sampled:0000-00-00
Sample Type 1:Lava
Text Description:
St. George Island, Group 1 type rocks (from Chang and others, 2009): "Group 1 rocks are commonly crystal poor (5-15 vol. % phenocrysts) and vesicular, with fine-grained, holocrystalline groundmasses. Phenocrysts are primarily olivine, although some rocks have clinopyroxene or opaque phenocrysts as well. The olivine phenocrysts are commonly equant or skeletal and vary widely in size and form from sample to sample and within rocks. Olivine compositions for seven rocks range from Fo90 to Fo61 and average Fo83. Clinopyroxene phenocrysts are generally small and euhedral and have average core and rim compositions of XMg=70 and 62, respectively. Clinopyroxene phenocrysts vary in color from tan to pink in plane-polarized light and often exhibit sector-zoning and occur in X- or star-shaped glomerocrystic clusters. The groundmasses generally consist of olivine, euhedral clinopyroxene, euhedral plagioclase laths, and opaque minerals. Modal nepheline was found in one rock (SG06-8). Abundant groundmass clinopyroxene is especially notable in group 1 rocks. The average clinopyroxene in the groundmass has a composition of XMg=66. Plagioclase compositions measured in two group 1 rocks are variable. The average plagioclase composition in sample SG05-28 is Ab36Or3An61, with two analyzed crystals having anomalous rims with an average composition of Ab48Or37An15. Plagioclase analyzed in sample SG05-31 is albite (Ab84Or12An3)."

References:
Petrogenesis of basaltic volcanic rocks from the Pribilof Islands, Alaska, by melting of metasomatically enriched depleted lithosphere, crystallization differentiation, and magma mixing

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedVolcanoEruptionLocation DescriptionText DescriptionSample IDMaterialSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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
SG05-1056.573355924287-169.49659574817Unknown, Unknown0000-00-00St. George volcanic fieldGroup 1St. George Island, Group 1 type rocks (from Chang and others, 2009): "Group 1 rocks are commonly crystal poor (5-15 vol. % phenocrysts) and vesicular, with fine-grained, holocrystalline groundmasses. Phenocrysts are primarily olivine, although some rocks have clinopyroxene or opaque phenocrysts as well. The olivine phenocrysts are commonly equant or skeletal and vary widely in size and form from sample to sample and within rocks. Olivine compositions for seven rocks range from Fo90 to Fo61 and average Fo83. Clinopyroxene phenocrysts are generally small and euhedral and have average core and rim compositions of XMg=70 and 62, respectively. Clinopyroxene phenocrysts vary in color from tan to pink in plane-polarized light and often exhibit sector-zoning and occur in X- or star-shaped glomerocrystic clusters. The groundmasses generally consist of olivine, euhedral clinopyroxene, euhedral plagioclase laths, and opaque minerals. Modal nepheline was found in one rock (SG06-8). Abundant groundmass clinopyroxene is especially notable in group 1 rocks. The average clinopyroxene in the groundmass has a composition of XMg=66. Plagioclase compositions measured in two group 1 rocks are variable. The average plagioclase composition in sample SG05-28 is Ab36Or3An61, with two analyzed crystals having anomalous rims with an average composition of Ab48Or37An15. Plagioclase analyzed in sample SG05-31 is albite (Ab84Or12An3)."SG05-10Whole Rock 43.746073304363 2.875634221231 13.458461458574 12.311701060312 0.21834951954451 9.6672799644096 11.346633287994 4.585762329644 1.2216775647388 0.9303937627022 97.059984882XRF12.311701060312 0.588770118 16.73428142 385.3713183 920.4860464 55.80022064 101.3482868 11.28868222 46.43493866 10.66183395 3.488582944 9.625139162 1.384341318 7.270107483 1.269243985 2.933193748 0.371106845 2.00780496 0.29316772 32.18946449 271.7090616 73.89911632 6.349162684 4.665952192 2.844424508 5.830389995 2.103587199 22.2448507 4882ICPMS 16.6 392.4 904.7 54.1 101.1 31.5 272.6 69.5 4.2 6.1 24.4 224.6 268.4 229 118.2 4882XRF

SAMPLE LOCATION

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