AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > Barth_1956_14

SAMPLE INFO : Barth_1956_14
Sample ID:Barth_1956_14
Station ID:Barth_1956_14
Latitude:56.58
Longitude:-169.63
Datum:NAD83
Date Sampled:1948-01-01
Sample Type 1:Lava
Sample Type 2:Sill
Text Description:
Sample of an apophysis of limburgite from a layer of semicrystalline, porphyritic hyalobasanite about 3 feet thick. It may be a flow, but is likely a sill. In the apophyses the rock becomes very dense and black, but still remains slightly porphyritic. Thin sections reveal that it corresponds to limburgite containing olivine, augite, and magnetite, but practically no feldspar, as primary phases. Olivine is often distinctly zoned. Augite is reddish in color, shows hourglass structure and is highly zoned. Positive 2V is around 60 degrees with strong dispersion r>v; the directions of the extinctions are also highly dispersed, ??c=45 degrees. It is a titaniferous augite. Zeolites are seen in cavities.

References:
Geology and petrology of the Pribilof Islands, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDSample Type 1Sample Type 2geologic 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
Barth_1956_14 56.58 -169.63 Barth, T. F. W. 1948-01-01 St. George volcanic field On the seashore, 1 mile south of Garden Cove, St. George Island Sample of an apophysis of limburgite from a layer of semicrystalline, porphyritic hyalobasanite about 3 feet thick. It may be a flow, but is likely a sill. In the apophyses the rock becomes very dense and black, but still remains slightly porphyritic. Thin sections reveal that it corresponds to limburgite containing olivine, augite, and magnetite, but practically no feldspar, as primary phases. Olivine is often distinctly zoned. Augite is reddish in color, shows hourglass structure and is highly zoned. Positive 2V is around 60 degrees with strong dispersion r>v; the directions of the extinctions are also highly dispersed, ??c=45 degrees. It is a titaniferous augite. Zeolites are seen in cavities. Barth_1956_14 Lava Whole Rock 40.4 3.25 13.16 12.44 0.2 11.26 10.34 3.4 0.8 0.86 100.4301NN5.347.62H2OM=2.24; H2OP=1.68NN

SAMPLE LOCATION

Contact AVO Privacy Accessibility Information Quality FOIA
URL: www.avo.alaska.edu/samples/sample_info.php
Page modified: July 14, 2014 13:37
Contact Information: AVO Web Team

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