AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > 47AC31

SAMPLE INFO : 47AC31
Sample ID:47AC31
Station ID:47AC31
Latitude:52.3488
Longitude:175.909
Datum:NAD83
Date Sampled:1947-01-01
Sample Type 1:Lava
Sample Type 2:Flow
Text Description:
Sample of an early flow from the northerly parasitic cone of Buldir Volcano. It is purplish gray, dense, and porphyritic, with a maximum grain size of 2 mm. Of the total volume, 35% is plagioclase phenocrysts, zoned, ranging in size from 2 to 0.5 mm, with a median composition of An60. 3% is olivine with a composition about Fa24. 2% is made up of augite and magnetite in the form of pseudomorphs after hornblende, and about 1% is hypersthene with a composition of about En60Fs40, judging from the negative 2V of about 60 degrees. Some hypersthene crystals have augite jackets. The groundmass, about 60% of the total volume, includes about 50% plagioclase, 3% hypersthene, 6% augite, and occasional prisms of cloudy apatite. The texture of the groundmass is also intergranular; between the plagioclase laths, ranging in length from 0.2 to 0.07 mm and in width from 0.02 to 0.08 mm, there are pyroxene granules from 0.04 to 0.01 mm in size and slightly smaller granules of magnetite.

References:
Geology of Buldir Island, Aleutian Islands, 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
47AC3152.3488175.909Unknown, Unknown1947-01-01 BuldirSample of an early flow from the northerly parasitic cone of Buldir Volcano. It is purplish gray, dense, and porphyritic, with a maximum grain size of 2 mm. Of the total volume, 35% is plagioclase phenocrysts, zoned, ranging in size from 2 to 0.5 mm, with a median composition of An60. 3% is olivine with a composition about Fa24. 2% is made up of augite and magnetite in the form of pseudomorphs after hornblende, and about 1% is hypersthene with a composition of about En60Fs40, judging from the negative 2V of about 60 degrees. Some hypersthene crystals have augite jackets. The groundmass, about 60% of the total volume, includes about 50% plagioclase, 3% hypersthene, 6% augite, and occasional prisms of cloudy apatite. The texture of the groundmass is also intergranular; between the plagioclase laths, ranging in length from 0.2 to 0.07 mm and in width from 0.02 to 0.08 mm, there are pyroxene granules from 0.04 to 0.01 mm in size and slightly smaller granules of magnetite.47AC31LavaWhole-rock 55.2 0.76 17.18 6.32 0.14 6.37 8.01 0.27Total calculated from mixed methods 100.49272NN2.613.98Cl=0.23; F=0.01; H2OM=0.12; H2OP=0.48NN units are percent 0.02units are percent 0.04n.d. 0 units are percent 0.005 n.d. 0 0.007units are percent 0.01 0.002units are percent 0.009units are percent 0.004n.d. 0units are percent 0.0009n.d. 0n.d. 0 272SPECNa2O V=3.77, M=FPHOT, R=272;K2O V=1.15, M=FPHOT, R=272;

SAMPLE LOCATION

Contact AVO Privacy Accessibility Information Quality FOIA
URL: avo.alaska.edu/samples/sample_info.php
Page modified: August 1, 2017 15:29
Contact Information: AVO Web Team

twitter @alaska_avo
facebook alaska.avo
email Receive volcano updates by email: USGS VNS

This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G19AC00060 and G19AC00171.

Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.