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SAMPLE INFO : SG06-3
Sample ID:SG06-3
Station ID:SG06-3
Latitude:56.587563381622
Longitude:-169.52298166473
Datum:NAD83
Date Sampled:0000-00-00
Sample Type 1:Lava
Text Description:
From Chang and others (2009): "SG06-3 is the only potassic trachybasalt (Le Bas and others, 1986) recovered from St. George. Both texturally and chemically, SG06-3 is different from all other rocks collected. Texturally, sections of the rock are relatively fine-grained, whereas other regions are coarse-grained. The rock contains olivine, titanaugite, plagioclase, K-feldspar, opaque minerals (ilmenite), and apatite. Natrolite is present in some vesicles. Olivine occurs as large, acicular phenocrysts with the lowest MgO contents of all rocks, with average core compositions of Fo40 and average rim compositions of Fo30. The olivine is also enriched in Ca relative to other rocks analyzed, with average cores and rims have 0.70 wt % and 0.91 wt % Ca, respectively. Clinopyroxene phenocrysts are large and abundant. They are pink plane-polarized light and are commonly zoned with darker pink cores. Many grains have sieved cores with opaque inclusions. Grains are euhedral to subhedral and have rims with corroded edges or a green alteration product along the edges. Clinopyroxene cores have average TiO2 contents of 2.83 wt % and Al2O3 contents of 4.68 wt %. Rims have average TiO2 contents of 2.16 wt % and Al2O3 contents of 3.70 wt %. Plagioclase compositions are more sodic than other rocks, with average core compositions of An44 and rims of An 22. Large, euhedral, needle-shaped apatite inclusions are abundant as inclusions in plagioclase grains."

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
SG06-356.587563381622-169.52298166473Unknown, Unknown0000-00-00St. George volcanic fieldGroup 3From Chang and others (2009): "SG06-3 is the only potassic trachybasalt (Le Bas and others, 1986) recovered from St. George. Both texturally and chemically, SG06-3 is different from all other rocks collected. Texturally, sections of the rock are relatively fine-grained, whereas other regions are coarse-grained. The rock contains olivine, titanaugite, plagioclase, K-feldspar, opaque minerals (ilmenite), and apatite. Natrolite is present in some vesicles. Olivine occurs as large, acicular phenocrysts with the lowest MgO contents of all rocks, with average core compositions of Fo40 and average rim compositions of Fo30. The olivine is also enriched in Ca relative to other rocks analyzed, with average cores and rims have 0.70 wt % and 0.91 wt % Ca, respectively. Clinopyroxene phenocrysts are large and abundant. They are pink plane-polarized light and are commonly zoned with darker pink cores. Many grains have sieved cores with opaque inclusions. Grains are euhedral to subhedral and have rims with corroded edges or a green alteration product along the edges. Clinopyroxene cores have average TiO2 contents of 2.83 wt % and Al2O3 contents of 4.68 wt %. Rims have average TiO2 contents of 2.16 wt % and Al2O3 contents of 3.70 wt %. Plagioclase compositions are more sodic than other rocks, with average core compositions of An44 and rims of An 22. Large, euhedral, needle-shaped apatite inclusions are abundant as inclusions in plagioclase grains."SG06-3Whole Rock 45.76099 4.3743 15.08331 13.96005 0.2278 4.06014 9.94937 3.91158 2.164 0.71618 98.512284882XRF13.96005 0.293837473 32.97969775 412.5676772 556.6796015 40.65778586 78.75098865 9.669575735 39.63052015 9.122557085 2.948026628 9.222281221 1.457198707 8.224889913 1.546252655 3.714163822 0.515744797 2.987199382 0.449060658 37.66966687 239.5267846 72.25560902 6.066149721 4.329172879 3.069140367 4.964624577 1.275917648 23.01138855 4882ICPMS 33.5 413.6 554.9 40.2 75.5 37.1 250.7 68.8 5 5.5 18.9 379 0 20.09615385 139.7 4882XRF

SAMPLE LOCATION

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