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Effective hydrological events in an evolving mid‐latitude mountain river system following cataclysmic disturbance—A saga of multiple influences

Cataclysmic eruption of Mount St. Helens (USA) in 1980 reset 30 km of upper North Fork Toutle River (NFTR) valley to a zero‐state fluvial condition. Consequently, a new channel system evolved. Initially, a range of streamflows eroded channels (tens of meters incision, hundreds of meters widening) and transported immense sediment loads. Now, single, large‐magnitude or multiple moderate‐magnitude ev

Monitoring network changes during the 2018 Kīlauea Volcano eruption

In the summer of 2018, Kīlauea Volcano underwent one of its most significant eruptions in the past few hundred years. The volcano’s summit and East Rift Zone magma system partially drained, resulting in a series of occasionally explosive partial caldera collapses, and widespread lava flows in the lower East Rift Zone. The Hawaiian Volcano Observatory (HVO) operates a robust permanent monitoring ne

The birth of a Hawaiian fissure eruption

Most basaltic explosive eruptions intensify abruptly, allowing little time to document processes at the start of eruption. One opportunity came with the initiation of activity from fissure 8 (F8) during the 2018 eruption on the lower East Rift Zone of Kīlauea, Hawaii. F8 erupted in four episodes. We recorded 28 min of high‐definition video during a 51‐min period, capturing the onset of the second

Geology of the Hawaiian Islands

Long known as the island chain farthest from any continental landmass, the Hawaiian Islands are the subaerial expression of volcanism above the relatively fixed Hawaiian hot spot as the Pacific plate drifts northwest above it. Each island is built by one or several overlapping shield volcanoes, some of the most voluminous on Earth. Plate translation creates the well-known age-progressive sequence

Monitoring volcanic deformation

Deformation signals recorded at volcanoes have long been used to infer the processes behind subsurface magma intrusions. Monitoring strategies vary greatly depending on several factors such as the activity of the individual volcano, access, available personnel, and funding.Certain geodetic monitoring methods, such as Electronic Distance Measurements, are inexpensive but require that scientists be

Origin and properties of hydrothermal tremor at Lone Star Geyser, Yellowstone National Park, USA

Geysers are rare geologic features that intermittently discharge liquid water and steam driven by heating and decompression boiling. The cause of variability in eruptive styles and the associated seismic signals are not well understood. Data collected from five broadband seismometers at Lone Star Geyser, Yellowstone National Park are used to determine the properties, location, and temporal pattern

The 2018 reawakening and eruption dynamics of Steamboat Geyser, the world’s tallest active geyser

Steamboat Geyser in Yellowstone National Park’s Norris Geyser Basin began a prolific sequence of eruptions in March 2018 after 34 y of sporadic activity. We analyze a wide range of datasets to explore triggering mechanisms for Steamboat’s reactivation and controls on eruption intervals and height. Prior to Steamboat’s renewed activity, Norris Geyser Basin experienced uplift, a slight increase in r

Generation of calc-alkaline magmas during crystallization at high oxygen fugacity: An experimental and petrologic study of tephras from Buldir Volcano, western Aleutian Arc, Alaska, USA

Despite agreement that calc-alkaline volcanism occurs at subduction zones and is responsible for the genesis of continental landmasses, there is no consensus on the source of the Fe-depleted signature hallmark to calc-alkaline volcanism. In this study, we utilize mafic tephras collected from Buldir Volcano to address the genesis of strongly calc-alkaline volcanic rocks (those with a low Tholeiitic

The cascading origin of the 2018 Kīlauea eruption and implications for future forecasting

The 2018 summit and flank eruption of Kīlauea Volcano was one of the largest volcanic events in Hawaiʻi in 200 years. Data suggest that a backup in the magma plumbing system at the long-lived Puʻu ʻŌʻō eruption site caused widespread pressurization in the volcano, driving magma into the lower flank. The eruption evolved, and its impact expanded, as a sequence of cascading events, allowing relative

Lava–water interaction and hydrothermal activity within the 2014–2015 Holuhraun Lava Flow Field, Iceland

Lava that erupted during the 2014–2015 Holuhraun eruption in Iceland flowed into a proglacial river system, resulting in aqueous cooling of the lava and an ephemeral hydrothermal system. We carried out a monitoring study of this system from 2015 to 2018 to document the cooling of the lava over this time, using thermocouple measurements and data-logging sensors. The heat loss rate from advection th

Diverse cataclysmic floods from Pleistocene glacial Lake Missoula

In late Wisconsin time, the Purcell Trench lobe of the Cordilleran ice sheet dammed the Clark Fork of the Columbia River in western Montana, creating glacial Lake Missoula. During part of this epoch, the Okanogan lobe also dammed the Columbia River downstream, creating glacial Lake Columbia in northeast Washington. Repeated failure of the Purcell Trench ice dam released glacial Lake Missoula, caus