Publications

The use of seismic noise interferometry to retrieve Green's functions and the analysis of volcanic tremor are both useful in studying volcano dynamics. Whereas seismic noise interferometry allows long-range extraction of interpretable signals from a relatively weak noise wavefield, the characterization of volcanic tremor often requires a dense seismic array close to the source. We here...

Swamp Lake, Yosemite National Park, is the only known lake in California containing long sequences of varved sediments and thus has the potential to provide a high-resolution record of climate variability. This preliminary analysis of the diatom assemblages from a 947-cm-long composite sediment core (freeze core FZ02–05; 0–67 cm, Livingstone core 02–05; 53–947 cm) shows that the lake has...

The 2009 eruption of Redoubt Volcano, Alaska, began with a phreatic explosion on 15 March followed by a series of at least 19 explosive events and growth and destruction of at least two, and likely three, lava domes between 22 March and 4 April. On 4 April explosive activity gave way to continuous lava effusion within the summit crater. We present an analysis of post-4 April lava dome...

The geology of Oldonyo Lengai volcano and the southernmost Lake Natron basin, Tanzania, is presented on this geologic map at scale 1:50,000. The map sheet can be downloaded in pdf format for online viewing or ready to print (48 inches by 36 inches). A 65-page explanatory pamphlet describes the geologic history of the area. Its goal is to place the new findings into the framework of...

Dating of many types of young (

Eruptive activity at the summit of Kilauea Volcano, Hawaii, beginning in 2010 and continuing to the present time is characterized by transient outgassing bursts accompanied by very long period (VLP) seismic signals triggered by rockfalls from the vent walls impacting a lava lake in a pit within the Halemaumau pit crater. We use raw data recorded with an 11-station broadband network to...

Estimating the mass, volume, and dispersal of the deposits of very small and/or extremely weak explosive eruptions is difficult, unless they can be sampled on eruption. During explosive eruptions of Halema‘uma‘u Crater (Kīlauea, Hawaii) in 2008, we constrained for the first time deposits of bulk volumes as small as 9–300 m3 (1 × 104 to 8 × 105 kg) and can demonstrate that they show...

On 29 May 2010, at approximately 11:48 UTC, an undersea volcano south of Sarigan in the Northern Mariana Islands (Figs. 1 and 2) erupted sending a cloud of volcanic ash and water vapor to 40,000 feet (12 km; Washington Volcanic Ash Advisory Center). Bathymetric data (Stern and Smoot, 1998; Embley et al., 2007) indicate an undersea vent exists at approximately 16.582° N and 145.821° E or...

Microtextures of juvenile pyroclasts from Kīlauea’s (Hawai‘i) early A.D. 2008 explosive activity record the velocity and depth of convection within the basaltic magma-filled conduit. We use X-ray microtomography (μXRT) to document the spatial distribution of bubbles. We find small bubbles (radii from 5 μm to 70 μm) in a halo surrounding larger millimeter-size bubbles. This suggests that...

A new database of volcanic fatalities is presented and analysed, covering the period 1600 to 2010 AD. Data are from four sources: the Smithsonian Institution, Witham (2005), CRED EM-DAT and Munich RE. The data were combined and formatted, with a weighted average fatality figure used where more than one source reports an event; the former two databases were weighted twice as strongly as...

Crystal-rich andesites that erupted from Redoubt Volcano in 2009 range from 57.5 to 62.5 wt.% SiO2 and have phenocryst and phenocryst-melt relations consistent with staging in the upper crust. Early explosive products are low-silica andesites (LSA,

Variations in the geochemistry and texture of amphibole phenocrysts erupted from Augustine Volcano in 2006 provide new insights into pre- and syn-eruptive magma storage and mixing. Amphiboles are rare but present in all magma compositions (low- to high-silica andesites) from the 3 month long eruption. Unzoned magnesiohornblende in the high- and low-silica andesites exhibit limited...