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3 June 2022
6.5-Extinctions: Dinosaurs, volcanoes, the space station, oh my!
Join us for our next six-part miniseries on Extinctions as we learn about the demise of the dinosaurs, what makes a comet “extinct,” the Cambrian and Triassic periods, volcanoes, and the aforementioned (planned) fiery end of the International Space Station!
4 October 2021
The seismic signals of the Chamoli landslide and debris flow
An interesting paper has just been published in the journal Science, (Cook et al. 2021), which looks at the seismic signals generated by the Chamoli rockslide and debris flow. It concludes that the event was fully detectable by seismic instruments located at up to 100 km from the event.
16 April 2021
Listening to avalanches half a state away
High on the broken pyramid of Iliamna Volcano, rotten rock held in place by volcano-warmed ice sometimes loses its grip. Several times over the years, rock-and-ice avalanches have blasted down Iliamna at 150 miles per hour. Left behind on the mountain’s face is a dirty, five-mile scar, in the same place as the last one.
24 July 2020
Earthquake adds missing piece to puzzle
Late in the evening of July 21, 2020, State Seismologist Michael West heard a text alarm. His phone informed him of a large earthquake beneath the ocean, just south of the Alaska Peninsula, about 60 miles southeast of the village of Sand Point. His first thought was that this — the biggest earthquake on the planet so far in 2020 — would cause a devastating tsunami. His second thought was that a longstanding earthquake mystery may have just been solved.
17 June 2020
Utah’s arches continue to whisper their secrets
Seismic studies assess the stresses and health of iconic rock structures.
15 June 2020
Instruments of Unusual Size
Volcanic craters could be the largest musical instrument on Earth, producing unique sounds that tell scientists what is going on deep in a volcano’s belly.
18 May 2020
Mt. St. Helens: 40 Years Later
On May 18, 1980, Mt. St. Helens erupted in Washington state, capping off a series of volcanic events that began on March 27th of that year. The May 18th explosions is credited with causing 57 deaths, >$1 billion in property damage, and forever changed the surrounding landscape.
3 March 2020
Researchers develop new explanation for destructive earthquake vibrations
Two researchers propose that rocks colliding inside a fault zone as an earthquake happens are the main generators of high-frequency vibrations. That’s a very different explanation than the traditional one, they say, and it could help explain puzzling seismic patterns made by some earthquakes. It could also help scientists predict which faults are likely to produce the more damaging quakes.
9 December 2019
Third Pod Live: O-klahoma, Where There’s Fracking, Oil, Faults, and More!
What’s it like to be a seismologist who’s studied the Marcellus Shale and San Andreas Fault, worked around the world from Pennsylvania to Rome, and is now a professor at the University of Oklahoma? We found out at AAA’s annual meeting earlier this year when we talked to assistant professor Brett Carpenter.
25 September 2019
Historic earthquakes suggest Trans-Mexican Volcanic Belt’s quiet regions are active
Seemingly low-hazard seismic regions in Mexico have experienced multiple, strong earthquakes since the 1500s, new research finds, suggesting the regions have many unmapped, active fault lines. The areas are inside the Trans-Mexican Volcanic Belt, home to roughly 40 percent of Mexico’s population, who may be unaware of the land’s seismic history.
6 September 2019
New research provides better look at ocean plate under Central America
Convection in Earth’s mantle is the “engine” driving plate tectonics. Hot material rises to the Earth’s surface from the boundary between the planet’s core and mantle, at a depth of about 3000 kilometers. Cold material then flows downward due to oceanic tectonic plates sinking into the mantle at subduction zones on the Earth’s surface.
23 May 2019
Aftershocks of 1959 earthquake rocked Yellowstone in 2017-18
Aftershocks from large earthquakes can take their time coming — almost six decades in the case of Yellowstone’s deadly Hebgen Lake earthquake of 1959.
16 May 2019
Earthquake in 2009 intensified American Samoa’s rising sea levels
The 2009, magnitude-8.1 Samoa earthquake dealt a great deal of damage to the Samoan Islands: Tsunami waves as high as 14 meters (46 feet) wiped out multiple villages, claiming nearly 200 lives and severely damaging water and electrical systems. New research reveals the damage is likely to continue in the island Tutuila, also known as American Samoa.
21 December 2018
Listening to the heartbeat of Alaska
Across Alaska and a sliver of western Canada, 280 seismic stations silently do their jobs. Hidden in dark holes drilled into rock in boreal forest, northern tundra and mountaintops, the instruments wait patiently for the next tremor.
22 October 2018
Quiescent British Columbia fault capable of producing large earthquakes
A Canadian fault scientists thought was inactive may actually be capable of producing large-magnitude earthquakes, a new study finds.
30 July 2018
Study reveals how sand dunes alter seismic waves
A new study finds that sand dunes act like seismic echo chambers and suggests new ways to filter out the noise they create in seismic surveys.
30 May 2018
Seismometer readings could offer debris flow early warning
Instruments designed to record earthquakes revealed information about debris-flow speed, the width of the flow and the size of boulders carried by the January 2017 mudslide in Montecito, California, and the location of the event, suggesting that the current generation of seismometers in the field could be used to provide an early warning of an incoming debris flow to residents in mudslide-prone areas.
6 December 2017
Scientists capture Earth’s “hum” on ocean floor
Researchers have successfully quantified Earth’s vibrational “hum” using seismic instruments on the bottom of the ocean. A new study determined at the ocean bottom the frequencies at which the Earth naturally vibrates, and confirmed the viability of using ocean instruments to study the phenomenon.
5 December 2017
Dark fiber: Using sensors beneath our feet to tell us about earthquakes, water and other geophysical phenomena
Scientists have shown for the first time that dark fiber – the vast network of unused fiber-optic cables installed throughout the country and the world – can be used as sensors for detecting earthquakes, the presence of groundwater, changes in permafrost conditions, and a variety of other subsurface activity.
28 September 2017
Planning to Get Underway
A typical research expedition has one or two chief scientists. Ours has 19…
