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SAMPLE INFO : SG06-8
Sample ID:SG06-8
Station ID:SG06-8
Latitude:56.603849669722
Longitude:-169.62289281431
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
SG06-856.603849669722-169.62289281431Unknown, 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)."SG06-8Whole Rock 41.87905 3.02201 13.16194 12.58807 0.20943 11.05942 10.97155 4.50644 1.97685 0.93165 97.565874882XRF12.58807 0.417257502 31.11118362 422.0116155 940.4590117 54.58575898 104.790292 12.28284502 48.73988813 9.918155 3.099238986 8.660814994 1.226266444 6.323201817 1.077308313 2.455749216 0.306589353 1.662582916 0.236655107 26.89132104 275.3556231 89.36292714 6.168411666 5.583229852 2.919608056 7.000391845 2.031380245 22.70472177 4882ICPMS 31.2 427 947 52.9 100.1 26.1 283.4 85.3 3.5 7.6 20.3 249.7 240.3 196.6461538 111.9 4882XRF

SAMPLE LOCATION

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