Lava domes are one of the conspicuous topographic features on volcanoes. The subsurface structure of the lava dome is important to discuss its formation mechanism. In the 1944 eruption of Volcano Usu, Hokkaido, a new lava dome was formed at its eastern foot. After the completion of the lava dome, various geophysical methods were applied to the dome to study its subsurface structure, but resulte...

0019-1035/$ see front matter 2009 Published by doi:10.1016/j.icarus.2009.09.011 * Corresponding author. Address: US Geological Su Program, 2255 N. Gemini Dr., Flagstaff, AZ 86001, Un E-mail address: [email protected] (W.L. Jaeger). Recently acquired data from the High Resolution Imaging Science Experiment (HiRISE), Context (CTX) imager, and Compact Reconnaissance Imaging Spectrometer for Mars (C...

The Gacun deposit is a typical Volcanic Hosted Massive Sulfide (VHMS) associated with Late Triassic seafloor calc-alkaline felsic volcanics. Studies of zircon ages, petrology, major and trace element geochemistry, Sr-Nd-Hf isotope geochemistry volcanic rocks from the Northern Yidun arc were undertaken in this paper. We reshaped magmatic system activity time, defined origin magma evolution, prop...

Risks and damages associated with lava flows propagation (for instance the most recent Etna eruptions) require a quantitative description of this phenomenon and a reliable forecasting of lava flow paths. Due to the high complexity of these processes, numerical solution of the complete conservation equations for real lava flows is often practically impossible. To overcome the computational diffi...

The Ca na dian Cor dil lera, where the Juan de Fuca oce anic plate is cur rently be ing subducted be neath the North Amer i can con ti nent, is com prised of oce anic and is land arc ter ranes accreted to the west ern edge of an ces tral North Amer ica since the Neoproterozoic (Gabrielse and Yorath, 1991; Mon ger et al., 1972; Mon ger and Price, 1979; Mon ger et al., 1982). The Me so zoic Necha...

Introduction: The cross-bedded, finely layered, altered, salty sediments observed at the Opportunity landing site on Mars were first interpreted as having been deposited by flowing and standing water in an evaporating acid lake environment [1] and, more recently [2], as having been deposited by the wind, in a near-playa setting similar to that at White Sands, NM, but complicated by an episode o...

Introduction: The rocks of Gusev Crater around the Spirit landing site are mainly olivine-bearing basalts [1-3], and are thought to have crystallized from lava with low viscosity [4]. These rocks are dark in color, vesicular, fine-grained, and have coatings of dust in varying degrees [5, 6]. However, the bedrock outcrops of the Columbia Hills are remarkably different from those near the landing...

[1] Side-scan sonar, submersible observations and sampling of lava flows from the East Pacific Rise, 17 –19 S constrain the character and variability of submarine volcanic eruptions along mid-ocean ridges. Nine separate lava sequences were mapped using relative age and lithological contrasts among recovered samples. Axial lengths activated during eruptive episodes range from 1 to >18 km; indivi...

During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather tha...

Twenty four samples of xenoliths and country rocks from the 1961 lava flow of Calbuco volcano have been studied. Fourteen samples have been analyzed for major elements and P, Ni, Ba, Cr, V, Zr, Sc, Y, and Sr. Five of these samples were further analyzed for Sm, Nd, Sr, and Pb isotope ratios. Seventeen samples were analyzed under the microscope and three samples were analyzed by microprobe fo...