Hundreds of earthquakes detected at Washington's Mt. Rainier
The quakes began just before 1:30 a.m. and have been occurring at a rate of several times per minute, said officials with the U.S. Geological Survey at the Cascade Volcano Observatory.
All the quakes have been occurring between 1.2 and 3.7 miles beneath the summit, and have been small in magnitude. The largest quake measured so far is 1.7, and none have been felt at the surface.
According to the USGS, quake swarms occur a couple of times a year, on average, under the state's tallest volcano, though this one is a bit unusual in terms of the number of quakes.
Still, the USGS said the volcano isn't showing any signs of alarming activity.
What Are The 4 Classic Types Of Volcanoes?
"Currently, there is no indication that the level of earthquake activity is cause for concern, and the alert level and color code for Mount Rainier remain at (Green/Normal)," the USGS wrote in a Tuesday morning press release. "Instruments do not show any detectable ground deformation at the volcano, and no anomalous signals have been seen on the infrasound monitoring stations."
Past swarms have been attributed to the circulation of floods interacting with preexisting faults, the USGS said.
Mt. Rainier will experience about nine quakes in a typical month. The last big quake swarm was in 2009 and measured over 1,000 quakes over three days, peaking at magnitude 2.3.
Can Volcanic Eruptions Affect The Weather?
Mt. Rainier is the closest volcano to the Puget Sound metro area, nestled about 45 miles southeast of Tacoma and 60 miles southeast of Seattle. Geological records last indicate Rainier erupted about 1,000 years ago.Original article source: Hundreds of earthquakes detected at Washington's Mt. Rainier
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
6 hours ago
- Yahoo
‘Larger swarm than anything we've seen': Rainier quakes reach historic levels
The recent swarm of small earthquakes at Mount Rainier has not only made national headlines but also history: Researchers have never recorded seismic activity like this before at the active stratovolcano. 'It's now a larger swarm than anything we've seen since we've been (seismic) monitoring anything at Mount Rainier,' Alex Iezzi, a research geophysicist, said in an interview Thursday. Researchers started seismic monitoring at Mount Rainier in the 1970s, according to Iezzi, who works for the U.S. Geological Survey's Cascades Volcano Observatory and said she conferred with other seismologists to identify the origin of observations at the mountain. Prior to then, it's unknown whether the volcano had experienced a larger swarm — a term defined as a cluster of earthquakes occurring in rapid succession in the same area. This swarm was first reported by the USGS on Tuesday morning. Since then, there have been hundreds of so-called volcano-tectonic earthquakes detected relatively deep below Mount Rainier's summit. Researchers say there's been no cause for concern or any indications that the volcano is on the verge of eruption — something that hasn't occurred in about 1,000 years. 'Which I think is good,' Iezzi added. Since Tuesday's roaring start, the seismic activity has significantly declined and continued to dwindle into Friday. Still, the swarm has surpassed Mount Rainier's last large one in 2009 'in terms of magnitude, total events, event rate, and energy release,' the USGS said in a status report Thursday. Mount Rainier is viewed as 'potentially the most dangerous volcano in the Cascade Range' due, in part, to its frequent earthquakes, according to the USGS. In ordinary times, Mount Rainier sees an average of nine quakes per month and swarms once or twice every year. Only Mount St. Helens has more temblors in the Cascade Range. Seismic activity is different in all volcanoes, and researchers are unsure why, Iezzi said. The recent earthquakes have presented researchers with new opportunities to learn more about Mount Rainier, which Iezzi called 'exciting,' even as their magnitudes have been small enough to go undetected by the public. 'Even if you were standing on Mount Rainier,' Iezzi said, 'you wouldn't be able to feel these.' Researchers currently hypothesize that the swarm, as others have been in the past, can be attributed to hydrothermal fluids — very hot water and gases deep in the volcano — moving through preexisting faults beneath the mountain. While earthquakes can cause volcanic eruptions, there has been no evidence of a correlation in the Cascades, and researchers have not seen any troubling signs during the swarm, according to Iezzi. Such warnings would include magma moving from the depth toward the surface, rockfalls and quakes increasing in size or becoming more shallow, she said. On its webpage about general Mount Rainier earthquake hazards, the USGS noted that quakes could trigger landslides, leading to volcanic mudflows, known as lahars, which could be dangerous to surrounding valleys. The agency said that the recent earthquakes are too small to pose a significant threat to hikers. A recent increase in rockfall and icefall at Mount Rainier has been attributed to warm temperatures unrelated to the swarm, it said. As of Friday morning, the Cascades Volcano Observatory and Pacific Northwest Seismic Network have located 391 earthquakes since the swarm's beginning and identified many others that it could not locate, according to the USGS. A quake can be detected by data, but it needs to be big enough and identified by enough seismometers to be pinpointed, Iezzi said. The earthquakes were between 1.5 and 4 miles in depth, with the largest being a 2.3 magnitude on Tuesday afternoon, the USGS said Friday. After being detected at rates up to several per minute when the swarm began, quakes were occurring three days later at a much slower rate. Researchers officially located 30 earthquakes per hour at the swarm's peak Tuesday but that figure had dwindled to a few per hour by Friday. By comparison, researchers in 2009 located 120 earthquakes at Mount Rainier during a three-day swarm — the largest being a 2.3 magnitude — although more than 1,000 quakes were detected, the USGS said. A 3.9-magnitude earthquake documented beneath Mountain Rainier in 1973 is the largest on record at the volcano, according to the agency. Iezzi said it was unclear when the current swarm would come to an end, a conclusion that researchers will reach when Mount Rainier returns to normal seismic activity. When the swarm began, the USGS said it likely would continue for several days and that most swarms at the volcano last less than a week. 'If the swarm lasts more than a week or so, that would be different than the last large swarm at Rainier in 2009,' the agency said in a statement Tuesday. For Iezzi, the swarm has served as 'a good reminder' that Mount Rainier is an active volcano, and she encouraged the public to keep aware of information distributed by the USGS. 'These are active systems,' she said, 'so we're constantly monitoring all the volcanoes in the Cascades.'
12 hours ago
Iliamna volcano in Alaska rumbling despite being dormant for over 100 years, scientists say
An Alaskan volcano that has been inactive for more than 100 years is showing signs of rumbling, according to scientists. However, there's a chance that the activity could be signs of a pending avalanche, rather than a volcanic eruption, NASA said. The Iliamna volcano, located near the Cook Inlet in southern Alaska, last erupted in 1867, but would still rumble every few years due to avalanches large enough to register on nearby seismic and infrasound instruments, according to NASA. The region has recently experienced a "flurry of shaking," according to the Alaska Volcano Observatory. On June 15, seismic activity ramped up at a "nearly continuous" rate for several hours, the observatory reported. The Operational Land Imager, a sensor aboard the Landsat 8 satellite, acquired an image of the volcano on June 10, prior to when the rumblings began. The seismic activity was similar to those caused by the initial slipping between rock and ice that preceded large avalanches on the volcano in the past, according to the AVO. Iliamna often experiences massive avalanches due to the combination of glacial ice weakened rock and volcanic heat, scientists say. Its peak is covered in glaciers, snow and ice and it sits on a base of Jurassic-era granite, according to the NPS. Since its last eruption, the volcano was recorded ejecting smoke and light ash in 1876, 1933, 1941 and 1947, according to the NPS. More reports of smoke and light ash were recorded for the late winter of 1956 or early spring of 1957, but those reports were not confirmed, the NPS said. In 1958, four columns of vapor were shooting out of vents on the eastern side of the volcano, according to the NPS. But that was the last time smoke appeared to be ejected by the volcano. Although Iliamna is remote -- located in the Chigmit Mountains within Lake Clark National Park and Preserve -- it is monitored closely be volcanologists due to its potential hazards. There are several communities within a 200-mile radius of the volcano that could be impacted in the event of an eruption, including Pedro Bay, Port Alsworth and Anchorage, according to the NPS. The AVO monitors 51 other active volcanos within the state, including the Redoubt Volcano, Iliamna's more eruptive neighbor, which is also located within the preserve. The U.S. Geological Survey currently has Iliamna at a "normal" volcano alert level.
Newsweek
a day ago
- Newsweek
New Stretch of Creeping California Fault Line Discovered
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Researchers have identified an actively creeping section of the Concord Fault running through local communities in California, potentially increasing the risk of large earthquakes in residential neighborhoods. According to the findings of a U.S. Geological Survey study, published by the Seismological Society of America on July 2, the Concord Fault not only has a creeping fault line, but the actively slipping section is not in the location it was previously believed to be. Newsweek has contacted the U.S. Geological Survey via email for comment. Why It Matters The Concord Fault may be capable of magnitude 6.7 or higher earthquakes, given its 20 km (12.4 mile) length, the study saud. As urban development overlays much of its path, it puts tens of thousands at risk the havoc brought by earthquakes and seismic activity. The fault runs through Walnut Creek and Concord, North Gate Road near Mount Diablo to Suisun Bay. An earthquake of a smaller magnitude, 5.4, along the fault line caused major destruction across the area in 1955. With this updated understanding, the California Geological Survey may designate the trace as part of an official Earthquake Fault Zone—a classification that would impact real estate disclosures, construction requirements, and long-term urban planning. A screenshot of a map in the U.S. Geological Survey's study, published by Seismological Society of America, which shows the location of the Bay Area Concord Fault line. A screenshot of a map in the U.S. Geological Survey's study, published by Seismological Society of America, which shows the location of the Bay Area Concord Fault line. U.S. Geological Survey/Seismological Society of America What To Know Researchers of the study traced a 7 km segment of the fault, dubbed the Madigan Avenue strand, and found, after reviewing more 30 locations with visible curb and sidewalk displacements, that the fault is moving by approximately 3 millimeters per year—consistent with movement rates on the fault's previously mapped northern half. While it has been known for decades that the northern half of the Concord fault is steadily creeping, in an area covering Concord through Acme Landfill, in Martinez, there is less understanding of the true paths of the lines in the southern section. The southern fault has moved the curbs as much as a handspan, around 18 centimeters, since the time they were installed, up to 60 years ago, the researchers found. Previously, the creeping fault line was mapped along the edge of Lime Ridge, but it has now been found to travel under various neighborhoods, as well as through Valle Verde Elementary School, in Walnut Creek. This means it is around 400 meters west of where the line was previously believed to run. Having more precise identification of the creeping fault line's location enables greater understanding of the seismic risks in the area, meaning that risk can be more accurately responded to. The study's authors emphasized that further research is necessary to determine whether previously undocumented strands of the Concord Fault may also exist, suggesting the region's seismic hazard could be more complex than currently understood. What People Are Saying Andrew Alden, an Oakland-based geologist, wrote on his website responding to the study: "Although faults that creep—moving slowly between large earthquakes—might soften large quakes by releasing a little energy, creep does continuous quiet damage on its own thanks to shifted curbs and cracked pavements." He added: "The Concord fault is completely occupied by human structures, whereas the more familiar Hayward fault has a fair share of vacant land that isn't harmed by either creep or quakes." He also wrote: "The south end of the fault is poorly mapped, and there are previous hints that it doesn't match its official location. All of that makes it important to check the area for signs of creep and make measurements of any evidence on the ground." What Happens Next As creeping fault line can cause damage to infrastructure and property, the new findings may prompt action from the California Geological Survey. A formal designation of the area as an official earthquake fault zone, would impact real estate transactions, land use, and building codes.
