Publications

Quantifying hydrothermal heat flux at meter-scale resolution over N0.25 km2 is required to bridge in-situ heat flux and satellite-based measurements. We advance a methodology that blends ground-based daytime optical and nighttime thermal infrared (TIR) imagery using Structure-from-Motion photogrammetry to map radiant hydrothermal heat flux over these scales at sites with low signal-to...

The 2016–2017 shallow submarine eruption of Bogoslof volcano in Alaska injected plumes of ash and seawater to maximum heights of ~ 12 km. More than 4550 volcanic lightning strokes were detected by the World Wide Lightning Location Network (WWLLN) and Vaisala’s Global Lightning Dataset (GLD360) over 9 months. Lightning assisted monitoring efforts by confirming ash-producing explosions in...

Few studies have examined the electrical properties of volcanic ash or considered the effects of physical characteristics, such as grain size and shape on its electrification. This study measures the resistivity of eight volcanic ash samples, three milled-samples and five natural ashfall samples from Alaska, U.S.A., using a current amplifier and examines the influence of particle size...

The 2016–2017 eruption of Bogoslof volcano involved at least 70 detected eruptive events between mid-December 2016 and August 30, 2017. Acquisition of high-resolution satellite imagery throughout the duration of the eruptive period allowed us to document and map the various morphologic changes that occurred on the subaerial part of Bogoslof Island. The emplacement of pyroclastic-flow and...

The 2016–2017 shallow submarine eruption of Bogoslof volcano produced numerous infrasound signals over 9 months that were recorded on six Alaska Volcano Observatory (AVO) arrays at ranges of 59 to over 800 km from the volcano. The lack of geophysical monitoring near Bogoslof and the repeated production of volcanic clouds to flight levels made monitoring by remote infrasound critical...

Controlled and natural source seismic data are used to build a 3-D P wave model for southern North Island, New Zealand, where the Pacific Plate subducts beneath the Australian Plate at a rate of ~41 mm/year. Our analysis reveals an abrupt along-strike transition in overthrusting plate structure within Cook Strait. Contrasts in properties (Vp, Vp/Vs, and Qs) likely reflects the degree of

Recent activity has provided new insights into the causes of surface deformation in and around the Yellowstone Caldera, a topic that has been debated since the discovery of caldera floor uplift more than four decades ago. An episode of unusually rapid uplift (>15 cm/yr) centered near Norris Geyser Basin along the north caldera rim began in late 2013 and continued until a Mw 4.9...

Bogoslof volcano, Alaska, experienced at least 70 explosive eruptions between 12 December 2016 and 31 August 2017. Due to its remote location and limited local monitoring network, this eruption was monitored and characterized primarily using remote geophysical and satellite techniques. SO2 emissions from Bogoslof were persistently detected by the Infrared Atmospheric Sounding...

Alteration in magmatic-hydrothermal systems leads to distinct changes in rock texture and mineralogy, and a strong redistribution of elements between fluid and rock. Here, we experimentally interacted andesite scoria with hyperacidic, high-sulfidation style fluids from Kawah Ijen volcano (Indonesia) at 25 and 100˚C, seeking to reproduce the textures observed in natural samples from this...

Ejection of ballistic blocks was a characteristic feature of the 2016–2017 Bogoslof eruption. High-resolution satellite images acquired throughout the duration of the 9-month long eruptive period permitted the recognition and mapping of ballistic blocks on the surface of Bogoslof Island. Many of the satellite images recorded the accumulation of ballistic material over several individual...

The high frequency of historical eruptions at Kīlauea Volcano presents an exceptional opportunity to address fundamental questions related to the transport, storage, and interaction of magmas within rift zones. The Nāpau Crater area on Kīlauea’s East Rift Zone (ERZ) experienced nine fissure eruptions within 50 years (1961–2011). Most of the magma intruded during these frequent eruptions...

Bogoslof volcano, in the central Aleutian arc, experienced a major eruption between December 2016 and August 2017 that was characterized by explosive activity (VEI 2 to 3) and the extrusion of lava domes. The Alaska Volcano Observatory tracked the activity in real-time using seismicity observed on distant stations as well as infrasound, lightning, satellite data, and occasional visual