Publications
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2004 volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory 2004 volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory
No abstract available.
Authors
Christina A. Neal, Robert G. McGimsey, Jim Dixon, Dmitry Melnikov
The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano
Stratigraphic and field data are used in conjunction with textural and chemical evidence (including data from scanning electron microscope, electron microprobe, X-ray fluorescence, X-ray diffraction, and instrumental neutron activation analysis) to establish that the 2003 eruption of Anatahan volcano was mainly phreatomagmatic, dominated by explosive interaction of homogeneous...
Authors
J.S. Pallister, F. A. Trusdell, I. K. Brownfield, D. F. Siems, J. R. Budahn, S.F. Sutley
Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust
Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850°C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635–661, 2005) have major-element and...
Authors
K. Ratajeski, T. W. Sisson, A. F. Glazner
Advantageous GOES IR results for ash mapping at high latitudes: Cleveland eruptions 2001 Advantageous GOES IR results for ash mapping at high latitudes: Cleveland eruptions 2001
The February 2001 eruption of Cleveland Volcano, Alaska allowed for comparisons of volcanic ash detection using two‐band thermal infrared (10–12 μm) remote sensing from MODIS, AVHRR, and GOES 10. Results show that high latitude GOES volcanic cloud sensing the range of about 50 to 65°N is significantly enhanced. For the Cleveland volcanic clouds the MODIS and AVHRR data have zenith angles...
Authors
Yingxin Gu, William I. Rose, D.J. Schneider, G.J.S. Bluth, I.M. Watson
Voluminous granitic magmas from common basaltic sources Voluminous granitic magmas from common basaltic sources
Granitic-rhyolitic liquids were produced experimentally from moderately hydrous (1.7-2.3 wt% H2O) medium-to-high K basaltic compositions at 700 MPa and f O2 controlled from Ni-NiO -1.3 to +4. Amount and composition of evolved liquids and coexisting mineral assemblages vary with fO2 and temperature, with melt being more evolved at higher fO2s, where coexisting mineral assemblages are more
Authors
T. W. Sisson, K. Ratajeski, W.B. Hankins, A. F. Glazner
Magmatic unrest beneath Mammoth Mountain, California Magmatic unrest beneath Mammoth Mountain, California
Mammoth Mountain, which stands on the southwest rim of Long Valley caldera in eastern California, last erupted ∼57,000 years BP. Episodic volcanic unrest detected beneath the mountain since late 1979, however, emphasizes that the underlying volcanic system is still active and capable of producing future volcanic eruptions. The unrest symptoms include swarms of small (M ≤ 3) earthquakes...
Authors
D.P. Hill, S. Prejean
Seismicity and tilt associated with the 2003 Anatahan eruption sequence Seismicity and tilt associated with the 2003 Anatahan eruption sequence
On May 10, 2003, the first historical eruption of Anatahan volcano in the western Pacific Mariana Islands was fortuitously recorded by a broadband seismograph installed on the island only 4 days prior to the eruption. This station, located 7 km WNW of the active crater, together with another broadband seismograph on Sarigan Island 45 km to the north, continued to operate throughout the 2...
Authors
S.H. Pozgay, R.A. White, D.A. Wiens, P.J. Shore, A.W. Sauter, J.L. Kaipat
Volcanic-ash hazard to aviation during the 2003-2004 eruptive activity of Anatahan volcano, Commonwealth of the Northern Mariana Islands Volcanic-ash hazard to aviation during the 2003-2004 eruptive activity of Anatahan volcano, Commonwealth of the Northern Mariana Islands
Within the Commonwealth of the Northern Mariana Islands (CNMI), Anatahan is one of nine active subaerial volcanoes that pose hazards to major air-traffic routes from airborne volcanic ash. The 2003-2004 eruptive activity of Anatahan volcano affected the region's aviation operations for 3 days in May 2003. On the first day of the eruption (10 May 2003), two international flights from...
Authors
M. Guffanti, J.W. Ewert, G.M. Gallina, G.J.S. Bluth, G.L. Swanson
Ion microprobe measurement of strontium isotopes in calcium carbonate with application to salmon otoliths Ion microprobe measurement of strontium isotopes in calcium carbonate with application to salmon otoliths
The ion microprobe has the capability to generate high resolution, high precision isotopic measurements, but analysis of the isotopic composition of strontium, as measured by the 87Sr/86Sr ratio, has been hindered by isobaric interferences. Here we report the first high precision measurements of 87Sr/86Sr by ion microprobe in calcium carbonate samples with moderate Sr concentrations. We...
Authors
P.K. Weber, C. R. Bacon, I.D. Hutcheon, B.L. Ingram, Joseph L. Wooden
Ongoing hydrothermal heat loss from the 1912 ash-flow sheet, Valley of Ten Thousand Smokes, Alaska Ongoing hydrothermal heat loss from the 1912 ash-flow sheet, Valley of Ten Thousand Smokes, Alaska
The June 1912 eruption of Novarupta filled nearby glacial valleys on the Alaska Peninsula with ash-flow tuff (ignimbrite), and post-eruption observations of thousands of steaming fumaroles led to the name ‘Valley of Ten Thousand Smokes’ (VTTS). By the late 1980s most fumarolic activity had ceased, but the discovery of thermal springs in mid-valley in 1987 suggested continued cooling of...
Authors
N. Hogeweg, T. E. C. Keith, E.M. Colvard, S. E. Ingebritsen
The May 2003 eruption of Anatahan volcano, Mariana Islands: Geochemical evolution of a silicic island-arc volcano The May 2003 eruption of Anatahan volcano, Mariana Islands: Geochemical evolution of a silicic island-arc volcano
The first historical eruption of Anatahan volcano began on May 10, 2003. Samples of tephra from early in the eruption were analyzed for major and trace elements, and Sr, Nd, Pb, Hf, and O isotopic compositions. The compositions of these tephras are compared with those of prehistoric samples of basalt and andesite, also newly reported here. The May 2003 eruptives are medium-K andesites...
Authors
J.A. Wade, T. Plank, R. J. Stern, D.L. Tollstrup, J.B. Gill, J. C. O’Leary, J.M. Eiler, R. B. Moore, J.D. Woodhead, F. Trusdell, T.P. Fischer, David R. Hilton
Thermal observations of gas pistoning at Kilauea Volcano Thermal observations of gas pistoning at Kilauea Volcano
Data acquired by three continuously recording thermal infrared thermometers situated on the north rim of Pu'u'O' o Crater at Kilauea Volcano during 2002 revealed episodes of periodic thermal pulses originating from a degassing vent on the crater floor. These thermal pulses are interpreted as gas release (jetting events) associated with gas pistoning, a mechanism observed previously at...
Authors
J.B. Johnson, A.J.L. Harris, R. Hoblitt