Publications

Finely crystalline amphibole or pyroxene rims that form during reaction between silicic host melt and cognate olivine xenocrysts, newly introduced during magma mixing events, can provide information about the timing between mixing and volcanic eruptions. We investigated rim growth experimentally by placing forsteritic olivine in rhyolitic and rhyodacitic melts for times between 25 and 622 h at 50

We present a self-consistent model for the interior of Io, taking the recent Galileo data into account. In this model, Io has a completely molten core, substantially molten mantle, and a very cold lithosphere. Heat from magmatic activity can mobilize volatile compounds such as SO2 in the lithosphere, and the movement of such cryogenic fluids may be important in the formation of surface features in

New earthquake probability calculations are made for the Sea of Marmara region and the city of Istanbul, providing a revised forecast and an evaluation of time-dependent interaction techniques. Calculations incorporate newly obtained bathymetric images of the North Anatolian fault beneath the Sea of Marmara [Le Pichon et al., 2001; Armijo et al., 2002]. Newly interpreted fault segmentation enables

Ninety years of historical landslide records were used as input to the Poisson and binomial probability models. Results from these models show that, for precipitation-triggered landslides, approximately 9 percent of the area of Seattle has annual exceedance probabilities of 1 percent or greater. Application of the Poisson model for estimating the future occurrence of individual landslides results

A careful survey of Galileo SSI global monitoring images revealed more than 80 apparent surface changes that took place on Io during the 5 year period of observation, ranging from giant plume deposits to subtle changes in the color or albedo of Patera surfaces. Explosive volcanic activity was discovered at four previously unrecognized centers: an unnamed patera to the south of Karei that produced

When raised to temperatures above the ice melting point, gas hydrates release their gas in well-defined, reproducible events that occur within self-maintained temperature ranges slightly below the ice point. This behavior is observed for structure I (carbon dioxide, methane) and structure II gas hydrates (methane-ethane, and propane), including those formed with either H2O- or D2O-host frameworks,

Sets of ridges of uncertain origin are seen in twenty-nine high-resolution Galileo images, which sample seven locales on Io. These ridges are on the order of a few kilometers in length with a spacing of about a kilometer. Within each locale, the ridges have a consistent orientation, but the orientations vary from place to place. We investigate whether these ridges could be a result of tidal flexin

Frequent, high-precision geodetic data have temporally correlated errors. Temporal correlations directly affect both the estimate of rate and its standard error; the rate of deformation is a key product from geodetic measurements made in tectonically active areas. Various models of temporally correlated errors are developed and these provide relations between the power spectral density and the dat

Eruption intensity is largely controlled by decompression‐induced release of water‐rich gas dissolved in magma. It is not simply the amount of gas that dictates how forcefully magma is propelled upwards during an eruption, but also the rate of degassing, which is partly a function of the supersaturation pressure (ΔPcritical) triggering gas bubble nucleation. High temperature and pressure decompres

Wai‘anae Volcano comprises the western half of O‘ahu Island, but until recently little was known about the submarine portion of this volcano. Seven new submersible dives, conducted in 2001 and 2002, and multibeam bathymetry offshore of Wai‘anae provide evidence pertaining to the overall growth of the volcano's edifice as well as the timing of collapses that formed the Wai‘anae slump complex. A pro

The 3 November 2002 Denali fault, Alaska, earthquake resulted in 341 km of surface rupture on the Susitna Glacier, Denali, and Totschunda faults. The rupture proceeded from west to east and began with a 48-km-long break on the previously unknown Susitna Glacier thrust fault. Slip on this thrust averaged about 4 m (Crone et al., 2004). Next came the principal surface break, along 226 km of the Dena

The northeast Mojave domain, a type locality for bookshelf faulting, is a region of east striking, left-lateral faults in the northeast corner of the Mojave block, a block otherwise dominated by ∼N40°W striking, right-lateral faults. Paleomagnetic evidence suggests that blocks within the domain have rotated clockwise about a vertical axis as much as 60° since 12.8 Ma [Schermer et al., 1996]. In 19