The Alaska Volcano Observatory's lightning detection system detected and located 171 lightning strokes during the August 18, 1992, eruption of the Crater Peak vent of Mount Spurr volcano in Alaska. The strokes, predominantly intracloud, were detected during a 70-minute interval that began more than an hour into the eruption. All detected strokes were of positive polarity. The spatial distributi...

An underwater glider with an acoustic data logger flew toward a recently discovered erupting submarine volcano in the northern Lau basin. With the volcano providing a wide-band sound source, recordings from the two-day survey produced a two-dimensional sound level map spanning 1 km (depth) × 40 km(distance). The observed sound field shows depth- and range-dependence, with the first-order spatia...

[1] We show evidence of very recent ( 25–40 Myr) geologic activity on the eastern flank of Olympus Mons volcano that includes a suite of fluvial (channel networks), volcanic (emplacement of lava flows and dikes), and tectonic (wrinkle ridges and troughs) processes. The combination and youth of these features confirms the importance of geological activity continuing to the present on Mars. Citat...

This paper is devoted to the study of the volcanoes of l-isogenies of elliptic curves over a finite field, focusing on their height as well as on the location of curves across its different levels. The core of the paper lies on the relationship between the l-Sylow subgroup of an elliptic curve and the level of the volcano where it is placed. The particular case l = 3 is studied in detail, givin...

A numerical model of the NW-Sabalan geothermal field was developed. The model covers a total area of 96 km and extends vertically from variable elevation of 2200-3600m a.s.l to 1,000m b.s.l. The model has 2,595 grid blocks in l4 horizontal layers. The boundary conditions and distributions of horizontal and vertical permeabilities were obtained by trialand-error matching of the initial temperatu...

detection of subsurface structures by means of gravity method can be used to determine mass distribution and density contrast of rock units. this distribution could be detected by different geophysical methods, especially gravity method. however, gravity techniques have some drawbacks and can't be always successful in distinguishing subsurface structures. performance of the gravity technique co...

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...

The orientation of crustal seismic anisotropy changed at least twice by up to 80 degrees because of volcanic eruptions at Ruapehu Volcano, New Zealand. These changes provide the basis for a new monitoring technique and possibly for future midterm eruption forecasting at volcanoes. The fast anisotropic direction was measured during three seismometer deployments in 1994, 1998, and 2002, providing...

The large-eruption rates of stratovolcanoes are modelled exchangeably, in order to derive an informative prior distribution as an input into a subsequent volcano-by-volcano hazard assessment. Derivation and implementation of the likelihood function is not straightforward, necessitating a detailed code verification. Analysis of the LaMEVE database suggests that most of the world’s stratovolcanoe...