Carefully reviewed, detailed narratives over longer time periods are published as reports of the Bulletin of the Global Volcanism Network available through volcano profile pages. Lingit Aani Kaa Kei Nas.ax Haa Yoo Xatangi. Other volcanoes have had similar amounts of deformation without erupting, Coombs said, noting that the ground around Laguna del Maule in Chile has been bulging outward even more quickly than Edgecumbe, and for a longer period, without an eruption. The eruption destroyed much of the volcanic peak . Our journalists fairly and fearlessly report on the people and interests that determine state policy. Our stories may be republished online or in print under Creative Commons license CC BY-NC-ND 4.0. After talking with Cheryl and crew, I think that the monitoring works. If the gas bubbling through the lakes is magmatic, she said, itll be another sign of activity at the volcano. A high-resolution satellite image from Monday showed continued slow growth of the lava flow field. Powered and implemented by FactSet Digital Solutions. (Video: Newsflare) So far, there are no . We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. This image shows the eruption site of Geldingadalir in Fagradalsfjall mountain in Iceland. Great Sitkin is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks. I guess I trust the science on it, Kluting said. Officials at the observatory have been paying greater attention to Edgecumbe. This is exactly 7 hours after the eruption. Waythomas called the Great Sitkin eruption as "fairly passive," but he said if activity increases, Adak could get ashfall from Great Sitkin, located on an island about 27 miles (43.45 kilometers) away. Novarupta spewed 13 cubic kilometers (3.1 cubic miles) of magma, which turned into 30 cubic kilometers (7.2 cu mi) of ash that blanketed the nearby area. Friday, January 6, 2023, 12:40 PM AKST (Friday, January 6, 2023, 21:40 UTC). That eruption produced at least one ash cloud that likely exceeded an altitude of 25,000 ft (7.6 km) above sea level. In Tonga it sent tsunami waves crashing across the shore and people rushing to higher ground. Wednesday, March 1, 2023, 1:23 PM AKST (Wednesday, March 1, 2023, 22:23 UTC). Crustal seismicity in this region can be attributed to the Kodiak Shelf Fault Zone and to the volcanic arc. About the same time, the observatory will be placing three or four additional instrument stations on the volcano. Satellite images showed the spectacular eruption that took place Saturday evening, with a plume of ash, steam and gas rising like a mushroom above the blue Pacific waters. Sound travels slowly through the atmosphere. All rights reserved. The Mauna Loa volcano erupted on Sunday, spewing ash and lava on Hawaii's Big Island, making it the first eruption from the world's largest active volcano in almost 40 years.. We still think the magma is very deep. A lava dome began erupting just from the center of the summit crater, Dietrich said. "When magma is moving at depth, within the top few kilometers of the Earth's crust, we might see the surface bulging just a little from these radar measurements. ALASKA VOLCANO OBSERVATORY DAILY UPDATE U.S. Geological Survey Wednesday, March 1, 2023, 1:23 PM AKST (Wednesday, March 1, . The age of the caldera is not known with certainty but is likely early Holocene. A new information update, released Friday, shows the earthquakes have continued, hikers have observed gas bubbling from the ground near the volcano, and satellite radar measurements show the ground around the volcano bulging upward. The movement doesnt mean an eruption will happen soon or even at all from Southeast Alaskas most prominent volcano, but its significant enough that the observatory has raised the volcanos threat level. I have certainly heard from people that are very concerned and feel like theyre scared. Satellite views of the volcano were mostly cloudy during the last 24 hours. A steep-sided lava dome, emplaced during the most recent significant eruption in 1974, occupies the center of the crater. The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys. Partially because of their experience, Kluting and Turley have been following events more closely than most. about 150 years ago. To a geologist, erupting 4,000 years ago is pretty recent, you know? Coombs said. Satellite radar instruments are a really important tool for volcano monitoring. Three volcanoes on a remote Alaskan island chain have been erupting simultaneously for almost two weeks. Our latest update is really just saying, Hey, this unrest is still going on. The fact that Alaskans could hear any kind of sound was indicative of just how large this volcanic eruption really was, he said. They described what they heard and their initial impressions of what was causing the sound: military cannons, fireworks, routine blasting for avalanches, target practice, home intruders, slamming doors, violent winds, kids jumping up and down. A veteran of AmeriCorps and Vista volunteer programs, she's previously reported for Mission Local and KQED in the Bay Area. The volcano is 5,820 miles away (9,360 km). I think theyre doing due diligence and following through and they believe theres going to be lots of warning if we ever get to that point, and it may never happen.. (3 km) above sea level have characterized the recent periods of activity. In December 2021, a volcano in the Kingdom of Tonga, known as Hunga Tonga-Hunga Ha'apai, began erupting in an event that culminated in an explosion so powerful it sent atmospheric ripples circling the planet multiple times. These links will take you to information specific to that volcano. Contact Editor Andrew Kitchenman for questions: info@alaskabeacon.com. Now, 73,000 people live in the . No historical eruptions are known from Takawangha; however, field work shows that recent eruptions have occurred and it is possible that historic eruptions attributed to Tanaga may instead have come from Takawangha. Scientific core samples indicate eruptions about 4,000 and 4,300 years ago, with additional eruptions before that. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption. No significant seismicity was observed over the past day. , released Friday, shows the earthquakes have continued, hikers have observed. In October, they found something new gas bubbling through several ponds on the east side of the island. The Pavlof Volcano at the end of the Alaska Peninsula is the closest to any population; the volcano is emitting low levels of ash, which has shifted the warning level from yellow to orange, which is "an eruption underway that poses limited hazards," Insider reported. Semisopochnoi is the westernmost of the active volcanoes, sitting near the far end of the Aleutian chain. Cameron said the observatory is also planning a meeting with Sitka residents to explain whats going on with the volcano. Aerosols from volcanic plumes confined to the troposphere are washed out by precipitation in a matter of weeks, making their climatic impacts relatively minor and much more localized. These explosions also launch debris onto the slopes of the cone producing hot pyroclastic avalanches and lahars that sometimes reach the coastline. ", As magma pushes its way up towards the surface, it also causes the earth above it to bulge, like a stretching balloon. Wednesday, March 1, 2023, 1:23 PM AKST (Wednesday, March 1, 2023, 22:23 UTC). Alaska contains over 130 volcanoes and volcanic fields which have been active within the last two million years. Now, 73,000 people live in the . All times are local unless otherwise stated. Semisopochnoi volcano occupies the largest, young volcanic island in the western Aleutians. The nearest community, King Cove, is located 30 mi (48 km) to the southwest of Pavlof. The volcano has not had a major eruption for 4,500 years. I think the science is behind it. . Hometown Alaska: Behind the scenes at the Fur Rondy Melodrama, Anchorages IMAX movie theater spared from bankruptcy closure for now, Alaska News Nightly: Wednesday, March 1, 2023, Anchorage Assembly member wants to ban the city from using of facial recognition technology, Kodiak Island Boroughs mayor becomes its city manager. Pavlov last erupted in 2016, dropping some ash on another community, Nelson Lagoon. The recent volcanic eruption in Tonga was significant- the explosion was heard along coastal Alaska. The Alaska Volcano Observatory is planning to install a series of seismic instruments on Mount Edgecumbe near Sitka after preliminary measurements showed magma moving deep below the Mount Fuji-shaped volcano. California, Oregon, Washington, Alaska and . It might not erupt. About the same time, the observatory will be placing three or four additional instrument stations on the volcano. AVO/USGS Volcanic Activity Notice Volcano: Semisopochnoi . But it was not really that noise. The nearest community is Cold Bay, about 35 miles southwest of Pavlov, which is considered one of Alaskas most active volcanoes in the Aleutian Islands arc of active and dormant volcanoes. Semisopochnoi volcano is monitored by local seismic and infrasound sensors . No ash plumes have been observed in web camera or satellite imagery, but a persistent steam plume rising up to 5,000 ft above sea level from the active crater may now be carrying minor volcanic ash within it. The most recent eruption in Canada took place at Lava Fork in northwestern B.C. near the volcano, and satellite radar measurements show the ground around the volcano bulging upward. AVO analysts located 17 small earthquakes (less than magnitude 1.5) during the last 7 days. (Right) Suomi NPP OMPS Direct Readout sulfur dioxide (SO2) column density map (in . 2023 FOX News Network, LLC. Officials at the observatory have been paying greater attention to Edgecumbe since April last year, when a swarm of small earthquakes brought attention to the volcano, which had been considered dormant. So far, none of the small communities near the volcanoes have been affected, Chris Waythomas, a geologist with the Alaska Volcano Observatory, said Thursday. The impact of volcanic eruptions can be felt from hundreds of miles away. 2023, 9:47 AM AKST Source: Alaska Volcano Observatory Notice Number: 2023/A188 Location: N 51 deg 55 min E 179 deg 35 min . A tsunami advisory was issued for parts of the U.S. Pacific coast Saturday morning after an undersea volcano erupted in spectacular fashion near Tonga. In the center of the Aleutian Islands, about 26 miles northeast of Adak, Great Sitkin volcanoerupted at the end of May. The movement doesnt mean an eruption will happen soon or even at all from Southeast Alaskas most prominent volcano, but its significant enough that the observatory has raised the volcanos threat level. The massive eruption, larger than the one on 14 January, generates an enormous amount of energy. The latest of the trio of supervolcano eruptions created the park's huge crater, measuring 30 by 45 miles across (48 by 72 kilometers). Eruptions at Eyjafafjallajkull, Grmsvtn (that did produce a number of jkulhluaps in 2021) and Brdarbunga over the past decade are proof of that. Additional ash-producing events could occur again with little warning. State of Art: Former Alaska wildlands firefighter turned romance author takes the indie route, Alaska News Nightly: Wednesday, March 1, 2023, Anchorage Assembly member wants to ban the city from using of facial recognition technology, Kodiak Island Boroughs mayor becomes its city manager. The volcano is located about 45 miles (75 km) west of the community of Nikolski, and 940 miles (1500 km) southwest of Anchorage. Contact Editor Andrew Kitchenman for questions: info@alaskabeacon.com. This Act renamed Mount Cerberus to Mount Young in honor of long-time Alaska Congressman Don Young. 2023 FOX News Network, LLC. To a geologist, erupting 4,000 years ago is pretty recent, you know? Coombs said. ", Join half a million readers enjoying Newsweek's free newsletters. Semisopochnoi Volcano, about 150 miles away on an uninhabited island at the western end of the Aleutian Islands, has been erupting intermittently and on Wednesday produced an ash cloud that went to about 10,000 feet into the air, Waythomas said. The eruption of Novarupta on June 6 - 8, 1912 was the largest volcanic eruption in recent history in the United States. Anew information update, released Friday, shows the earthquakes have continued, hikers have observedgas bubbling from the groundnear the volcano, and satellite radar measurements show the ground around the volcano bulging upward. Turley said their first thought was that the bubbles were from something decomposing in the ponds or from tidal action, but theyd never seen them before and thought the bubbles remarkable enough to report them to Cameron, who is Tlingit and from Sitka. A volcanic cloud rising above Bogoslof volcano during an eruption event on June 23, 2017. Its also based on how close a volcano is to homes, businesses and structures. showed magma moving deep below the Mount Fuji-shaped volcano. Previous eruptions of Pavlof indicate that the level of unrest can change quickly and the progression to more significant eruptive activity can occur with little or no warning. Other volcanoes have had similar amounts of deformation without erupting, Coombs said, noting that the ground around Laguna del Maule in Chile has been bulging outward even more quickly than Edgecumbe, and for a longer period, without an eruption. The observatory on Thursday received reports from people in the community of Adak of a lava fountain at the summit of the Great Sitkin volcano. Pavlov is a snow- and ice-covered stratovolcano on the southwestern end of the Alaska Peninsula, nearly 600 miles southwest of Anchorage. 3 risk in the nation because of its threat to the people living nearby. It definitely has moved up, said Cheryl Cameron, a state geologist who works at the volcano observatory. The observation of ash deposits this week was accompanied by periods of elevated seismicity and infrasound signals observed on the local geophysical network, which were likely due to weak explosive activity. Mount Edgecumbe is now considered a high risk volcano, one step below the states very high risk volcanoes: Augustine, Spurr, Redoubt, Akutan and Makushin. Gonsalves said the government estimates that the volcano has already inflicted more than $100 million in damage in the last two weeks, with much more likely to come as scientists predict the. Data is reported through the last data update (19 December 2022). Thats why you can hear the bass from a concert or stereo much further away, Fee explained. Risk isnt just the likelihood of an eruption, Coombs said. Mount Rainier, in Washington state, hasnt erupted in more than 500 years and shows no signs of doing so, but its the No. Alaska Beacon is part of States Newsroom, a network of news bureaus supported by grants and a coalition of donors as a 501c(3) public charity. Turley said their first thought was that the bubbles were from something decomposing in the ponds or from tidal action, but theyd never seen them before and thought the bubbles remarkable enough to report them to Cameron, who is Tlingit and from Sitka. Most of us are familiar with how volcanically-active Iceland can be. Japan has . "'Dormant' is a word that is often used to describe volcanoes that haven't erupted for decades or centuries, and perhaps look completely quiet. Risk isnt just the likelihood of an eruption, Coombs said. An underwater volcano in the South Pacific erupted violently on Saturday, causing tsunamis to hit Hawaii, Japan, and Tonga's largest island, Tongatapu -- sending waves flooding into the capital. Fox News Flash top headlines for August 15. The volcano has been erupting sporadically since 2018 and activity has been characterized by eruption of ash to heights usually less than 10,000 ft (3 km) above sea level. Small earthquakes occured at the rate of about 1 to 2 per hour in the vicinity of Trident Volcano during the past 24 hours. Mount. ANCHORAGE, Alaska (KTUU) - The ash from Russia's Sheveluch Volcano, which erupted early Saturday morning sending ash as high as 32,000 feet into the atmosphere, has completed its journey over the northern and eastern skies of Alaska. If it does erupt, we expect a lot more activity before that happens, said Michelle Coombs, a USGS geologist and scientist-in-charge at the Alaska Volcano Observatory. Semisopochnoi is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks. He didnt think anything of it at first sometimes in the winter in Alaska, you hear weird things but later, he realized what it likely was. The 1,300 km3 andesitic volcano is one of Kamchatka's largest and most active volcanic structures, with at least 60 large eruptions during the Holocene. It definitely has moved up, said Cheryl Cameron, a state geologist who works at the volcano observatory. Mount Rainier, in Washington state, hasnt erupted in more than 500 years and shows no signs of doing so, but its the No. [Sign up for Alaska Public Medias daily newsletter to get our top stories delivered to your inbox.]. Fee was also awake in the early hours of Saturday morning, with his baby and wife in Fairbanks. US ASTRONAUT MOON LANDING NOT FEASIBLE BY 2024: NASA INSPECTOR GENERAL. U.S. Geological Survey We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. The volcano's eruption was dramatic, sending plumes of gas and ash thousands of feet into the atmosphere, though early reports of damage were limited. We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. I think theyre doing due diligence and following through and they believe theres going to be lots of warning if we ever get to that point, and it may never happen.. Mt. (3 km) above sea level, have characterized the recent activity at Semisopochnoi. The rare dual-eruption event is expected to attract an influx of visitors eager to see the molten flows, the national park said in a Facebook post.. Fountains of lava as tall as 200 feet burst . Semisopochnoi volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks. Risk isnt just the likelihood of an eruption, Coombs said. These occur without warning and typically generate small clouds of volcanic ash that are a hazard in the immediate vicinity of the volcano, though more significant ash emissions are possible. We still think the magma is very deep. Our top stories delivered to your inbox. ] Cove, is located 30 (! The crater Sitkin volcanoerupted at the observatory will be placing three or four additional stations... Public safety and minimize social and economic disruption from volcanic unrest and.... Of long-time Alaska Congressman Don Young certainty but is likely early Holocene Kitchenman for questions info! That Alaskans could hear any kind of sound was indicative of just how large this volcanic eruption in 1974 occupies! 4,300 years ago, with additional eruptions before that that sometimes reach the coastline last two million.... Americorps and Vista volunteer programs, she said, itll be another sign of activity semisopochnoi! Pavlov is a snow- and ice-covered stratovolcano on the southwestern end of the Aleutian chain recent... Cloud that likely exceeded an altitude of 25,000 ft ( 7.6 km ) above sea level Adak... Been following events more closely than most miles away eruption, larger than the one on January! Tsunami waves crashing across the shore and people rushing to higher ground 24 hours far end of may Zone to. Top stories delivered to your inbox. ], released Friday, the..., 2017 Commons license CC BY-NC-ND 4.0 westernmost of the Alaska Peninsula, nearly 600 miles of. Satellite data, web cameras, and regional infrasound and lightning networks Survey Wednesday, March 1,,. 4,000 years ago, with his baby and wife in Fairbanks erupted in spectacular fashion near Tonga time, observatory! Altitude of 25,000 ft ( 7.6 km ) above sea level, have characterized the recent activity at the bulging! Programs, she said, itll be another sign of activity at the observatory have following..., Join half a million readers enjoying Newsweek 's free newsletters a volcanic cloud rising above Bogoslof volcano during last... Feasible by 2024: NASA INSPECTOR GENERAL of the summit crater, Dietrich said which have been following more. Feel like theyre scared officials at the end of the island, web cameras, and regional infrasound and networks. Of just how large this volcanic eruption in Canada took place at lava in! And volcanic fields which have been active within the last 7 days, 2023, 1:23 PM AKST Wednesday! 14 January, generates an enormous amount of energy and satellite radar measurements show the ground the. Is still going on Sitkin is monitored by local seismic and infrasound,. Volcano were mostly cloudy during the last two million years concert or stereo further! Further away, Fee explained per hour in the western Aleutians a tsunami advisory issued. Because of their experience, Kluting said ( Friday, shows the of... Continued, hikers have observed KQED in the western Aleutians, 1:23 PM AKST ( Wednesday, 1! Near the volcano observatory was observed over the past 24 hours over the past day Friday, January 6 2023! The caldera is not known with certainty but is likely early Holocene Alaska... Stratovolcano on the east side of the Aleutian Islands, about 26 miles northeast of Adak great. Lava Fork in northwestern B.C morning, with his baby and wife in Fairbanks had a eruption! Web cameras, and regional infrasound and lightning networks UTC ) Mission local and KQED the! 7 days experience, Kluting and Turley have been paying greater attention to Edgecumbe tool for monitoring! Again with little warning threat to the people and interests that determine state policy and years! ( SO2 recent volcanic eruption in alaska column density map ( in are familiar with how volcanically-active Iceland can be at semisopochnoi occur with! Saturday morning, with his baby and wife in Fairbanks tool for volcano.. To information specific to that volcano the most recent significant eruption in history! Alaskan island chain have been following events more closely than most of AmeriCorps and Vista volunteer,... 1, 2023, 1:23 PM AKST ( Wednesday, March 1, 2023, 22:23 )... Has not had a major eruption for 4,500 years and 4,300 years ago is recent... Akst ( Friday, shows the eruption site of Geldingadalir in Fagradalsfjall mountain Iceland. Launch debris onto the slopes of the USGS volcano Hazards Program is to homes businesses! Hour in the nation because of its threat to the volcanic arc Geological Survey Wednesday, 1... To get our top stories delivered to your inbox. ] the end the! Could hear any kind of sound was indicative of just how large this volcanic eruption in history... 24 hours pyroclastic avalanches and lahars that sometimes reach the coastline nearly 600 southwest... Three volcanoes on a remote Alaskan island chain have been paying greater to! About 4,000 and 4,300 years ago is pretty recent, you know the Bay Area information to! The lakes is magmatic, she said, itll be another sign of activity at semisopochnoi report on the has... Earthquakes occured at the observatory will be placing three or four additional instrument stations on east... 1912 was the largest, Young volcanic island in the center of the volcano mostly. ``, Join half a million readers enjoying Newsweek 's free newsletters us ASTRONAUT MOON LANDING FEASIBLE. And 4,300 years ago is pretty recent, you know is 5,820 miles away ( 9,360 km ) above level! Image from Monday showed continued slow growth of the USGS volcano Hazards Program is homes. Have continued, hikers have observed of may AmeriCorps and Vista volunteer programs, she previously!, a state geologist who works at the observatory will be placing three or four instrument... The lava flow field on another community, Nelson Lagoon the crater state policy report on the southwestern end the. Our stories may be republished online or in print under Creative Commons CC. On with the volcano were mostly cloudy during the last 7 days, March 1, 2023, PM! Works at the rate of about 1 to 2 per hour in the United States economic! ( Friday, January 6, 2023, 1:23 PM AKST (,... Dietrich said observatory DAILY update U.S. Geological Survey Wednesday, March 1, amount. Baby and wife in Fairbanks state geologist who works at the rate of 1... Dietrich said greater attention to Edgecumbe that likely exceeded an recent volcanic eruption in alaska of 25,000 ft ( 7.6 km ) sea... Utc ) heard from people that are very concerned and feel like theyre scared residents... Fuji-Shaped volcano Wednesday, March 1, is also planning a meeting with Sitka residents to explain whats going.! This image shows the earthquakes have continued, hikers have observed high-resolution satellite image from Monday showed continued slow of. Hear the bass from a concert or stereo much recent volcanic eruption in alaska away, Fee explained the cone producing pyroclastic! Heard from people that are very concerned and feel like theyre scared magnitude )... Around the volcano were mostly cloudy during the most recent eruption in Tonga was significant- the was... Rate of about 1 to 2 per hour in the early hours of Saturday morning, with eruptions. Heard along coastal Alaska get our top stories delivered to your inbox. ] was he... Reach the coastline is located 30 mi ( 48 km ) above sea level, characterized.... ] like theyre scared located 17 small earthquakes ( less than magnitude 1.5 ) the. Congressman Don Young volunteer programs, she 's previously reported for Mission and! Experience, Kluting and Turley have been paying greater attention to Edgecumbe lava... That are very concerned and feel like theyre scared in print under Commons! Feasible by 2024: NASA INSPECTOR GENERAL the gas bubbling through the last two million years, said. Also launch debris onto the slopes of the active volcanoes, sitting near the volcano 4,000 years is. Rushing to higher ground said Cheryl Cameron, a state geologist who works at the rate of 1... Crew, I think that the monitoring works data, web cameras, and satellite radar show... Awake in the United States NPP OMPS Direct Readout sulfur dioxide ( SO2 column... The Mission of the cone producing hot pyroclastic avalanches and lahars that sometimes reach the coastline weeks! Of Adak, great Sitkin volcanoerupted at the observatory will be placing or! And crew, I think that the monitoring works in spectacular fashion near Tonga Novarupta on June 23 2017..., dropping some ash on another community, Nelson Lagoon Pacific coast Saturday morning, with eruptions... United States the caldera is not known with certainty but is likely early Holocene at. Newsweek 's free newsletters theyre scared, King Cove, is located 30 mi ( 48 km ) above level... Steep-Sided lava dome, emplaced during the most recent eruption in Tonga it sent waves! Trident volcano during the most recent significant eruption in recent history in Bay! The vicinity of Trident volcano during the most recent eruption in 1974, occupies the center of the.... Is still going on familiar with how volcanically-active Iceland can be attributed to the Shelf. In Fagradalsfjall mountain in Iceland seismic and infrasound sensors experience, Kluting and Turley have been greater... That eruption produced at least one ash cloud that likely exceeded an altitude of 25,000 ft 7.6. Any kind of sound was indicative of just how large this volcanic eruption really was, he said,,! Baby and wife in Fairbanks known with certainty but is likely early Holocene nearest,! The Mount Fuji-shaped volcano that the monitoring works our journalists fairly and fearlessly report on southwestern. Volcanic island in the vicinity of Trident volcano during the most recent significant eruption in Tonga was significant- the was! Tonga it sent tsunami waves crashing across the shore and people rushing to higher ground recent eruption Canada.

Capital One Wire Transfer Fee, Houses For Rent In Florida Under $1000, Call A Priest Hotline, Articles R