A seismometer measures the movement of the earth. Gary S Chapman / Getty Images
By Fabian Schmidt
Researchers have discovered an interesting similarity in two of the largest recent earthquakes in Japan and Chile: a strange large-scale ground movement back and forth in the months leading up to the quake.
<p>These earthquakes are among the 10 strongest ever measured: the 2011 Tohoku-oki seaquake off the coast of Japan registered 9.0 on the moment magnitude scale, triggering the devastating tsunami that destroyed the Fukushima Nuclear Power Plant. It was the fourth-strongest quake in the last 100 years. The 2010 seaquake off the coast of the Maule region of Chile, occupies sixth place on the list. </p><p>Researchers from the Geoforschungszentrum Potsdam (GFZ) along with collaborators from Chile and the United States have now discovered astonishing similarities in the months before both quakes: multiple strange reversals of ground motion — an extremely slow "wobbling" of the continental plate, so to speak.</p><p>Lead author, <a href="https://www.gfz-potsdam.de/en/staff/jonathan-bedford/sec41/" target="_blank">geophysicist Jonathan Bedford</a>, along with a team of geodesists, geologists and seismologists, evaluated the movements of ground stations of the Global Navigation Satellite System (GNSS).</p><p>These ground stations continuously track the distances to multiple GNSS satellites that orbit the earth in elliptical orbits. After these distances have been established, and given the estimates of the satellite positions, geodesists are able to define the motion of points on the Earth within a terrestrial reference frame.</p><p>In Japan, there is a very dense network of ground stations. Although the network in Chile was not as dense in 2010, it was sufficient to obtain the data.</p>
Whole Continental Plate 'Wobbles'
<p>Bedford and his colleagues analyzed how the ground stations in Japan and Chile had moved in the five years before the two quakes. They noticed that the motion of the continental plate on which the stations are located had been reversed several times in the last five months before the quake (in the case of Japan) and seven months (in the case of Chile). The researchers published <a href="https://doi.org/10.1038/s41586-020-2212-1" target="_blank">their results</a> in the scientific journal <a href="https://www.nature.com/articles/s41586-020-2212-1" target="_blank">Nature</a>.</p><p>Both plate boundaries are subduction zones. Subduction is the process of one plate diving under another. In both study regions, the oceanic plates are subducting underneath the continental plates and meet at a place called the trench, which for both cases is submerged under the ocean. Normally, the continental plate is pressed by the oceanic plate and thus pushed away from the trench. However, the geophysicists have now discovered that this movement was first reversed in the direction of the trench, then away from the trench, then back towards the trench again.</p>Same Movement Over Thousands of Kilometers
<p>They call this phenomenon "wobbling," due to its appearance in the GNSS time series. The amplitude of this movement is not particularly great — it was only between 4 and 8 millimeters — but Bedford points out that this is significant compared to the relative plate motion that can be a few centimeters per year. Furthermore, the spatial extent of the signal extended thousands of kilometers along the plate boundaries.</p><p>"It is a common assumption that deeper subduction proceeds at a fairly constant speed in between large earthquakes," says Bedford. "Our study shows that this assumption is an oversimplification. In fact, its variability might be a key factor in understanding how the largest earthquakes nucleate." </p><p>With global satellite tracking now becoming better and better, and with accurate data available for the first time in decades, earthquake researchers have an ever-increasing ability to make such observations.</p><p>"We can now trace movements back decades," says Bedford. "In the next stage, we'd like to monitor the changes in near real time."</p>Not Suitable as an Early Warning System
<p>Until now, seismologists have been more able to say <em>where</em> large earthquakes are likely to occur — less able to say <em>when</em>. By simply calculating the magnitude of the last large earthquake in a region and knowing the average relative plate velocity, one can estimate when that fault will be mature enough to sustain a repeat event, although there are great uncertainties in this approach. This is because sometimes a fault will rupture only over a smaller area (e.g. with a "large" magnitude 8 event) and other times it will rupture over many magnitude 8 regions all at once (e.g. in a "mega" magnitude 9 event).</p><p>Could an observed untypical plate movement therefore give us a better warning of an imminent earthquake? Not really. </p><p>"It would not be wise for a geophysicist to issue such a warning," is Bedford's sobering answer. "The observed signals of this study are not necessarily precursory movements of a major quake."</p><p>More research is necessary and as a matter of principle, people in known earthquake areas should not let their guard down. </p><p>"The general public should always be prepared," Bedford warns.</p>
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A USGS map showing the location of a 6.5 magnitude quake that shook Idaho Tuesday evening. USGS
Idaho residents were rattled Tuesday evening by the biggest earthquake to shake the state in almost 40 years.
<p>The 6.5 magnitude quake struck just before 6 p.m. local time 73 miles northeast of Meridian, <a href="https://apnews.com/ee4018c9240bd4768dbea25c40712198" target="_blank">The Associated Press reported</a>. It caused no known damage or injuries, but plenty of surprise. </p>
<p>"At first I thought it was thunder, weird thunder, but then the house was moving and I realized this is an earthquake — a really big earthquake," Boise resident Melissa Hawkins, 44, <a href="https://eu.usatoday.com/story/news/nation/2020/03/31/earthquake-idaho-the-whole-house-rattling/5100853002/" target="_blank">told USA Today</a>.</p><p>All told, more than two million people might have felt the earthquake, according to U.S. Geological Survey (USGS) figures reported by The Associated Press. Reports of shaking came from as far as Spokane, Washington; Bozeman, Montana; and Salt Lake City, Utah, according to USA Today.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1245151137918889984" id="twitter-embed-1245151137918889984" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1245151137918889984&created_ts=1585702139.0&screen_name=jessphoenix2018&text=Here%27s+an+interesting+visualization+of+%22Did+You+Feel+It%3F%22+reports+for+the+%23IdahoEarthquake.+Head+over+to+the+%40USGS%E2%80%A6+https%3A%2F%2Ft.co%2FdELFgCELYt&id=1245151137918889984&name=Jess+Phoenix+%F0%9F%8C%8B" frameborder="0" data-rm-shortcode-id="0e18395a82f4d973bcc848b284b09f44"></iframe><p>Evaro, Montana resident Shannon Patton at first blamed her health.</p><p>"I actually thought I was having a dizzy spell to begin with due to my migraine," Patton told USA Today in an email. "Our light fixtures were shaking and one of our signs on our pantry door almost fell off."</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1245138509263859712" id="twitter-embed-1245138509263859712" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1245138509263859712&created_ts=1585699128.0&screen_name=AmbroseElaine&text=Earthquake+near+Boise%2C+Idaho.+Watching+now+for+the+four+horsemen...+https%3A%2F%2Ft.co%2FqavCnyBGLl&id=1245138509263859712&name=Elaine+Ambrose" frameborder="0" data-rm-shortcode-id="84f59635d11f02fd671f511c633c6819"></iframe><p>Despite tweets warning of the apocalypse, Caltech seismologist Dr. Lucy Jones told The Associated Press that the Idaho region has an earthquake around this size every 30 to 40 years.</p><p>The last was actually much worse: the 6.9 Borah Peak earthquake of 1983. That quake struck near the town of Challis and killed two school children when they were buried under rubble, <a href="https://edition.cnn.com/2020/03/31/us/idaho-boise-earthquake-trnd/index.html" target="_blank">CNN reported</a>. It also cost the state $12.5 million in property damage.</p><p>The 1983 quake was along a "normal fault," which causes vertical movement, Jones told The Associated Press. Tuesday's quake, on the other hand, was on an unmapped "strike-slip fault," which causes horizontal movement. Jones said it was not uncommon for faults in remote areas to go unmapped, since they are less likely to cause damage.</p>
<p>"This is one that wasn't obvious enough to be mapped before now," Jones told The Associated Press.</p><p>But she further explained on Twitter why Idaho sees earthquakes.</p><p>"Idaho is part of the Basin and Range tectonic province. Everything west of the Wasatch Mtns. is getting slowly stretched out as a bit of North America tries to cling to the Pacific plate," she wrote.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1245148206121381889" id="twitter-embed-1245148206121381889" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1245148206121381889&created_ts=1585701440.0&screen_name=DrLucyJones&text=Idaho+is+part+of+the+Basin+and+Range+tectonic+province.+Everything+west+of+the+Wasatch+Mtns.+is+getting+slowly+stre%E2%80%A6+https%3A%2F%2Ft.co%2FmmHtOWAeJU&id=1245148206121381889&name=Dr.+Lucy+Jones" frameborder="0" data-rm-shortcode-id="c0b53a7963c00f719946684fd594c2f1"></iframe><p>Jones said to expect aftershocks, and the USGS reported a 4.8 magnitude one about an hour after, according to USA Today. More, smaller tremors were felt throughout the evening.</p>
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5.4 Earthquake Rattles Croatian Capital, Forcing Residents out of Coronavirus Lockdown
23 March
Popular
A Croatian fireman walks past rubble in a street of downtown Zagreb, Croatia on March 22, 2020, after a 5.3 magnitude earthquake hit the country. DAMIR SENCAR / AFP via Getty Images
Croatia's capital of Zagreb was rocked Sunday by its strongest earthquake in 140 years, which pushed people out into the streets at exactly the moment they were supposed to stay indoors to fight the spread of the coronavirus.
<p>The earthquake caused widespread damage, injured 17 and forced hospitals to evacuate, <a href="https://www.theguardian.com/world/2020/mar/22/croatia-earthquake-causes-widespread-damage-zagreb" target="_blank">The Guardian reported</a>. But earthquake survivors also had to worry about staying apart while out in the streets.</p><p>"Keep your distance. Don't gather together. We are facing two serious crises, the earthquake and the epidemic," Interior Minister Davor Bozinovic advised, as <a href="https://www.bbc.co.uk/news/world-europe-51995861" target="_blank">BBC News reported</a>.</p><p>Among the locations evacuated was a maternity hospital, according to The Guardian. Mothers and their babies stood outside in a freezing parking lot before the army moved them and their incubators to a new location.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1241704716792406018" id="twitter-embed-1241704716792406018" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1241704716792406018&created_ts=1584880448.0&screen_name=angjelinaahmeti&text=A+destructive+5.4+magnitude+%23earthquake+hit+Zagreb%2C+Croatia+this+morning+-+the+strongest+in+140+years%21%F0%9F%92%94+It+breaks+m%E2%80%A6+https%3A%2F%2Ft.co%2FBffpxXBKXD&id=1241704716792406018&name=Angjelina%F0%9F%91%BC%F0%9F%8F%BB" frameborder="0" data-rm-shortcode-id="e1866f0fe935fa497350b41cc2383e94"></iframe>
<p>The quake was a magnitude 5.4 according to the <a href="https://www.emsc-csem.org/Earthquake/earthquake.php?id=840695#summary" target="_blank">European Mediterranean Seismological Centre</a>, and it rattled the city at 6:24 a.m. local time.</p><p>Initial reports said one 15-year-old was killed, but doctors then said the patient was in critical condition, <a href="https://apnews.com/3f05271ed03ec32a04c96b3587420fdb?utm_campaign=SocialFlow&utm_medium=AP&utm_source=Twitter" target="_blank">The Associated Press reported</a>. The quake also damaged several buildings, including the historic Zagreb cathedral and the country's parliament, The Guardian reported.</p><p>One spire of the cathedral, which was rebuilt following another earthquake in 1880, collapsed, and the parliament building was so badly damaged that its speaker Gordan Jandroković said sessions would have to be postponed.</p><p>"The damage is quite extensive. Walls and stairways have cracked on the upper floor and one section of the roof has been destroyed," Jandroković said.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1241607134309052418" id="twitter-embed-1241607134309052418" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1241607134309052418&created_ts=1584857183.0&screen_name=anacasey17&text=Zagreb+Cathedral+tower+is+damaged+https%3A%2F%2Ft.co%2FPazq7ghNOp&id=1241607134309052418&name=Ankica+Zovko" frameborder="0" data-rm-shortcode-id="30e9484c901a58a7cc32467c18798ed7"></iframe>
<p>But the earthquake wasn't the only danger facing Croatians Sunday morning. They also had to consider COVID-19, which has sickened at least 235 people in the country so far. Zagreb is on partial lockdown, The Associated Press reported. Residents had been advised to avoid public places and only gather in groups of five with distance between them.</p><p>Health Minister Vili Beros told residents to stand two meters (approximately 6.6 feet) apart as they waited in the streets.</p><p>"Earthquakes are dangerous, but coronavirus is even more so," Beros said.</p><p>Soldiers wore masks as they shoveled debris.</p><p>The government initially advised people to leave their homes, BBC News reported, but Zagreb's Mayor Milan Bandic then recommended they return home, since 80 percent of Zagreb residents live in structures reinforced with concrete.</p><p>Prime Minister Andrej Plenkovic acknowledged the confusion of the situation.</p><p>"We have two parallel cris[es] that contradict each other," he said, according to The Associated Press.</p>
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Workers evacuate the Lonja del Comercio (Commerce Market) in Havana, Cuba after an earthquake rattled the island Tuesday. ADALBERTO ROQUE / AFP via Getty Images
A 7.7 magnitude earthquake shook the Caribbean Tuesday, rattling people from Miami to Mexico.
<p>The quake struck at 2:10 p.m. and had its epicenter 86 miles northwest of Montego Bay, Jamaica and 87 miles southwest of Niquero, Cuba. It prompted evacuations in Miami and opened sinkholes in the Cayman Islands, but so far there have been no reports of major damages or injuries.</p><p>"This one was serious. It put the fear of God into many people today," Jamaican ad executive Knolly Moses <a href="https://www.npr.org/2020/01/28/800547848/powerful-earthquake-strikes-caribbean-but-no-reports-of-injuries-or-damage?t=1580289383484" target="_blank">told NPR</a>.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1222242314346565632" id="twitter-embed-1222242314346565632" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1222242314346565632&created_ts=1580240250.0&screen_name=DrLucyJones&text=A+M7.7+has+been+reported+northwest+of+Jamaica.+It+appears+to+be+the+transform+fault+boundary+between+the+North+Amer%E2%80%A6+https%3A%2F%2Ft.co%2Frc0ZLJi30M&id=1222242314346565632&name=Dr.+Lucy+Jones" frameborder="0" data-rm-shortcode-id="T92IQC1580304264"></iframe>
<p>The Pacific Tsunami Warning Center initially warned that "hazardous <a href="https://www.ecowatch.com/tag/tsunami">tsunami</a> waves" could impact Belize, Cuba, Honduras, Mexico, the Cayman Islands and Jamaica, <a href="https://www.bbc.co.uk/news/world-latin-america-51287493" target="_blank">BBC News reported</a>. However, those warnings were later withdrawn.</p><p>The earthquake was felt in Kingston, Jamaica and Havana, Cuba. It was also strongly felt in Cuba's largest eastern city, Santiago, The Associated Press reported. However, the colonial city emerged unscathed.</p><p>"It felt very strong but it doesn't look like anything happened," Belkis Guerrero, who works at a Roman Catholic cultural center there, told <a href="https://apnews.com/3666c9ed40bea298b1147d9456eb8230" target="_blank">The Associated Press</a>.</p><p>In the Cayman Islands, the shaking blew the covers off manholes and blasted sewage into the streets, Cayman Islands hospital psychiatrist Dr. Stenette Davis told The Associated Press. The Cayman Islands also felt a series of aftershocks — one reached a magnitude of 6.1. Water was shut off to most of Grand Cayman Island and schools were closed Wednesday.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1222252627355820032" id="twitter-embed-1222252627355820032" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1222252627355820032&created_ts=1580242709.0&screen_name=naomiyamamoto&text=Big+%23earthquake+off+coast+of+Jamaica.+This+photo+was+taken+at+Cricket+Square+in+George+Town%2C+Cayman+Islands.+Bricks%E2%80%A6+https%3A%2F%2Ft.co%2FwRkDynzr4B&id=1222252627355820032&name=Naomi+Yamamoto" frameborder="0" data-rm-shortcode-id="HIJK8N1580304264"></iframe>
<p>Cayman Compass editor-in-chief Kevin Morales said that the island was unaccustomed to earthquakes and that newspaper staff were not at first sure what they were experiencing.</p><p>"It was just like a big dump truck was rolling past," Morales told The Associated Press. "Then it continued and got more intense."</p><p>In Miami, meanwhile, the shaking prompted evacuations from at least eight high-rise buildings in downtown Miami, Miami City Commissioner Ken Russell told CNN affiliate WPLG, as the <a href="https://edition.cnn.com/2020/01/28/us/miami-earthquake-evacuations-jamaica/index.html" target="_blank">main network reported</a>.</p><p>High-rise employee Jose Abreu at first thought the vibrations he felt were from a fan.</p><p>"I thought it was the fan acting up on me. I didn't think anything of it," he said. "I just went along, until the building announcement came through the speakers and I just evacuated in the back of the building."</p><p>Ryan Gold of the U.S. Geological Survey told the Miami Herald that it was not surprising that the quake was felt in Miami, as BBC News reported.</p><p>"It's a very large earthquake which can produce a lot of seismic energy," he said.</p>
<iframe width="100%" height="150" scrolling="no" class="rm-shortcode twitter-embed-1222249298320089090" id="twitter-embed-1222249298320089090" lazy-loadable="true" src="/res/community/twitter_embed/?iframe_id=twitter-embed-1222249298320089090&created_ts=1580241915.0&screen_name=BrandonOrrWPLG&text=Shaking+from+the+7.7+magnitude+Caribbean+Earthquake+felt+in+high-rises+as+far+north+as+Aventura%2C+FL%2C+just+north+of%E2%80%A6+https%3A%2F%2Ft.co%2Fbde5Mq68Bc&id=1222249298320089090&name=Brandon+Orr" frameborder="0" data-rm-shortcode-id="V58PU81580304264"></iframe>
<p>The earthquake was also felt in five Mexican states including Veracruz, on the Gulf Coast, The Associated Press reported.</p>
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A crack caused by an earthquake is seen in La Guancha boardwalk in Ponce, Puerto Rico on Jan. 9, 2020. RICARDO ARDUENGO / AFP via Getty Images
By Richard Aster
Multiple strong and damaging earthquakes in southern Puerto Rico starting around Dec. 28, 2019 have killed at least one person, caused many serious injuries and collapsed numerous buildings, including a multistory school in the town of Guánica that luckily was empty at the time. These quakes are the most damaging to strike Puerto Rico since 1918, and the island has been under a state of emergency since Jan. 6, 2020.
<p><br>This flurry of quakes includes onshore and offshore events near the town of Indios and along Puerto Rico's southwestern coast. So far it has included 11 <a href="https://www.usgs.gov/faqs/foreshocks-aftershocks-whats-difference?qt-news_science_products=0#qt-news_science_products" target="_blank">foreshocks</a> – smaller earthquakes that preceded the largest event, or mainshock – with magnitudes of 4 and greater. Major quakes occurred on Jan. 6 (magnitude 5.8) and Jan. 7 (magnitude 6.4 mainshock), followed by numerous large aftershocks.</p><p><a href="https://scholar.google.com/citations?user=khkdN24AAAAJ&hl=en" target="_blank">Seismologists like me</a> are constantly working to better understand <a href="http://www.ecowatch.com/tag/earthquakes">earthquakes</a>, including advancing ways to help vulnerable communities before, during and after damaging events. The physics of earthquakes are astoundingly complex, but our abilities to forecast future earthquakes during a strong sequence of events in real time is improving.</p><p>Forecasting earthquakes is not a strict prediction – it's more like a weather forecast, in which scientists estimate the likelihood of future earthquake activity based on quakes that have already occurred, using established statistical laws that govern earthquake behavior.</p>
<h2>An Undersea Fault Zone</h2><p>Puerto Rico spans a complex boundary between the Caribbean and North American <a href="https://pubs.usgs.gov/gip/dynamic/tectonic.html" target="_blank">tectonic plates</a>, which are sliding past each other in this region at a relative speed of about 2 centimeters per year. Over geologic time, this motion has created the Muertos Trough, a <a href="https://seismo.berkeley.edu/blog/2020/01/07/deadly-earthquakes-in-the-muertos-trough.html" target="_blank">15,000-foot depression in the sea floor</a> south of the island.</p><p>This plate boundary is riddled with interconnected fault structures. The present activity is occurring on and near at least three interrelated large faults.</p>
<img lazy-loadable="true" src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjUwNzkwMi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMzM2OTQ1M30.C0LJHoMTL55fyQZTmDiwfJoDGDE7LL05nkvSztuLjvY/img.jpg?width=980" id="9c749" class="rm-shortcode" data-rm-shortcode-id="35f84d58ad0b90d9de549e5688b53c59" data-rm-shortcode-name="rebelmouse-image" />
Multiple faults crisscross the eastern Caribbean. Those outlined in red have a potential to generate a large earthquake. The arrow at top right shows the direction of the North American plate's motion relative to the Caribbean plate. Red stars denote intensity centers for past earthquakes. USGS
<p>Faults are pre-existing weak zones between stronger rocks. In response to surprisingly small force (stress) changes, they rapidly slip to produce earthquakes. The "hair-trigger" nature of fault slip means that predicting the precise timing, location and size of individual quakes is extremely challenging, if not impossible.</p><p>During an earthquake sequence, changing stresses act on nearby fault systems as stress is gradually redistributed within the earth. This process generates thousands of protracted aftershocks.</p><p>Many earthquake sequences simply start with the mainshock. But it is not especially rare for scientists to recognize after the fact that foreshocks were occurring before the main event. Improvements in earthquake instrumentation and analysis are helping scientists detect foreshocks more often, although we have not yet figured out how to recognize them in real time.</p>
<h2>Will One Shock Lead to Another?</h2><p>Researchers have known for over a century that the rate of earthquakes following a mainshock declines in a way that we can characterize statistically. There is also a well-established relationship between the magnitude of earthquakes and their relative number during an earthquake sequence. In most seismically active regions, for a decrease of one magnitude unit – say, from 4.0 to 3.0 – people can expect to experience about 10 times as 3s compared to 4s in a given time period.</p><p>Using such statistical relationships allows us to forecast the probability and sizes of future earthquakes while an earthquake sequence is underway. Put another way, if we are experiencing an aftershock sequence, we can project the future rate of earthquakes and what magnitudes we expect those quakes to have.</p>
<p>
<em>Richard Aster is a professor of geophysics and the department head at Colorado State University.<br/>
</em><em>Disclosure statement: Richard Aster has received funding for earthquake research from the National Science Foundation, Los Alamos National Laboratory, Sandia National Laboratories and the U.S. Geological Survey. He is a past president of the Seismological Society of America (SSA) (2009-2011) and current chair of the board of directors of Incorporated Research Institutions for Seismology. Aster also chairs the U.S. Geological Survey's Advanced National Seismic System Advisory Committee, and is a member of the Southern California Earthquake Center Advisory Council.</em>
</p><p>
<em>Reposted with permission from <a href="https://theconversation.com/earthquake-forecast-for-puerto-rico-dozens-more-large-aftershocks-are-likely-129874" target="_blank">The Conversation</a>.</em>
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Residents walk past the eruption of Taal volcano in the Philippines Monday. TED ALJIBE / AFP via Getty Images
The second-most active volcano in the Philippines belched to life on Sunday when it sent a cloud of ash miles into the air that forced thousands to evacuate and shuttered the airport in the capital of Manila.
<p>The eruption of the Taal volcano continued Monday when it began gushing lava, <a href="https://apnews.com/11cacd39a4aa509097d44d090e20c93d" target="_blank">The Associated Press reported</a>. People living nearby also felt tremors, and the country's volcanic institute warned of a potential "volcanic <a href="https://www.ecowatch.com/tag/tsunami" target="_self">tsunami</a>" in the lake that surrounds the volcanic island, according to <a href="https://www.nytimes.com/2020/01/12/world/asia/philippines-taal-volcano.html?smid=fb-nytimes&smtyp=cur&fbclid=IwAR1M6DseVcDdHa4lLzjX2gokfd6ewMyG441oZHhM1ClYTabMLoLQRYflPOo" target="_blank">The New York Times</a>.</p><p>"The <a href="https://www.ecowatch.com/tag/earthquakes" target="_self">earthquakes</a> were strong, and it felt like there was a monster coming out," Cookie Siscar, who heard about the eruption from her husband Emer, told The New York Times.</p>
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<p>The Philippine Institute of Volcanology and Seismology <a href="https://twitter.com/phivolcs_dost/status/1216329536536637440" target="_blank">raised</a> the volcano's Alert Level to four out of five Sunday evening, indicating that a "hazardous eruption" is "imminent."</p><p>Taal volcano is located on an island around 40 miles south of Manila in the Philippines' Batangas province, according to The New York Times. Around 6,000 people live on the island itself, but people in the surrounding areas are also at risk. More than 13,000 people in Batangas and nearby Cavite province have been evacuated to shelters so far, according to The Associated Press. But authorities expect that number to balloon. More than 450,000 people are estimated to live within the volcano's danger zone, the Official United Nations Office for the Coordination of Humanitarian Affairs (OCHA) said. </p>
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<p><a href="https://www.bbc.co.uk/news/world-asia-51086961" target="_blank">According to BBC News</a>, Batangas province has already declared a "state of calamity."</p><p>So far, the major impact has been ash. The volcano sent ash, steam and pebbles six to nine miles into the air Sunday, The Associated Press reported. The ash spread more than 62 miles north of the volcano, reaching Manila, where it forced the international airport to close. More than 500 flights were canceled.</p><p>The airport was able to resume "partial operations" Monday morning, BBC News reported. But schools were closed, government work paused and the Philippines stock exchange canceled trading for the day.</p><p>In the villages, meanwhile, the ashfall threatened homes and livelihoods.</p>
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<p>"My father is missing," evacuee Irene de Claro, whose father stayed behind when the rest of the family fled a village in Batangas, told The Associated Press. "We don't know too what happened to our house because the ash was up to our knees, it was very dark and the ground was constantly shaking when we left. Most likely there's nothing for us to return to. We're back to zero."</p><p>Fear of losing farms or livestock means some people are refusing to evacuate.</p><p>"We have a problem, our people are panicking due to the volcano because they want to save their livelihood, their pigs and herds of cows," Mayor Wilson Maralit of Balete town told DZMM radio, as The Associated Press reported. "We're trying to stop them from returning and warning that the volcano can explode again anytime and hit them."</p><p>So far, there have been no deaths or injuries reported.</p><p>Taal volcano has erupted more than 30 times in 500 years, according to BBC News. The last time was in 1977.</p>Because it lies on the Pacific "Ring of Fire," the Philippines is often threatened by earthquakes and volcanic eruptions. It also weathers around 20 typhoons or major storms every year, according to The Associated Press. The last was less than a month ago, when <a href="https://www.ecowatch.com/typhoon-philippines-2642182411.html?rebelltitem=1#rebelltitem1" target="_self">Typhoon Phanfone</a> struck the predominantly Catholic country on Christmas Day.
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A high sea borders the roadside on the French overseas island of Mayotte, in the Indian Ocean on Sept. 29, 2019.ALI AL-DAHER / AFP via Getty Images
Mysterious hums that were heard around the world in 2018 have now been identified as the rumblings of a magma-filled reservoir deep under the Indian Ocean, announcing the birth of an underwater volcano, according to a new study, as CNN reported.
<p>Researchers started to detect seismic movement from the birth of the volcano in May and June of 2018, which eventually led to a humming noise that radiated thousands of miles away from where the volcano was born about 22 miles off the coast of Mayotte in the Indian Ocean, one of several in the Comoros archipelago found between Mozambique and Madagascar, as <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a> reported.</p><p>For months, the forming volcano produced tiny <a href="http://www.ecowatch.com/tag/earthquakes" target="_self">earthquakes</a> and a slight humming too weak to feel. That changed on Nov. 11, 2018 when the new volcano announced its birth by sending seismic waves all over the world that were felt in Kenya, Chile, Canada and Hawaii, nearly 11,000 miles away. For almost half an hour, the seismic waves produced a humming that got louder and louder, as <a href="https://www.washingtonpost.com/nation/2020/01/09/earthquake-creates-underwater-volcano/" target="_blank">The Washington Post</a> reported.</p><p>Researchers developed new seismological methods to create a year-long timeline to reconstruct what happened during the formation of the new volcano. They published their results this week in the journal <a href="https://www.nature.com/articles/s41561-019-0505-5" target="_blank">Nature Geoscience</a>.</p><p>Geologists around the world were alerted to the bizarre humming on Nov. 11, 2018 when a New Zealand geologist <a href="https://twitter.com/matarikipax/status/1061590953876582402?s=20" target="_blank">tweeted</a>, "This is a most odd and unusual seismic signal. Recorded at Kilima Mbogo, Kenya ..." with a link to data from the U.S. Geological Survey, as as <a href="https://www.washingtonpost.com/nation/2020/01/09/earthquake-creates-underwater-volcano/" target="_blank">The Washington Post</a> reported.</p><p>That led to a worldwide effort by seismologists to pinpoint the source of the low frequency humming. A team of German scientists took on the task of recreating what happened that led to the formation of a brand new volcano.</p>
<p>This is "the first time we've really observed the birth of a volcano on the sea floor," said Simone Cesca, a seismologist at the GFZ German Research Center for Geosciences in Potsdam, Germany and the paper's lead author, to <a href="https://www.washingtonpost.com/nation/2020/01/09/earthquake-creates-underwater-volcano/" target="_blank">The Washington Post</a>.</p><p>The paper explains how magma from a reservoir buried about 20 miles under the <a href="http://www.ecowatch.com/tag/oceans" target="_self">ocean</a> floor migrated upward from the earth's mantle and pushed itself through the earth's crust. Once it breached the ocean floor, the magma could flow through the opening and create a new volcano, as <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a> reported.</p><p>"It took only [a] few weeks for the magma to propagate from the upper mantle to the seafloor, where a new submarine volcano was born," said Cesca in an email to <a href="https://www.livescience.com/underwater-volcano-hum.html" target="_blank">Live Science</a>.</p><p>The scientists traced 7,000 tectonic quakes during the study. Tectonic quakes happen when Earth's tectonic plates get stuck as they move alongside one another and pressure builds for them to move, which causes an earthquake, as <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a> reported.</p><p>The seismologists also recorded 407 unusual signals coming from the site of the magma chamber near Mayotte. Those unusual signals, called Very Long Period signals, are the low humming that is similar to a double bass or the peel of a large bell, according to <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a>. The Very Long Period signals last 20 to 30 minutes and can be detected hundreds of miles away.</p>
<p>Without the Very Long Period signal that hummed so dramatically on Nov. 11, seismologists probably would not have discovered the underwater volcano, said Stephen P. Hicks, who studies earthquake seismology at the Imperial College of London and who is unrelated to the team of Mayotte researchers, to <a href="https://www.washingtonpost.com/nation/2020/01/09/earthquake-creates-underwater-volcano/" target="_blank">The Washington Post</a>.</p><p>A "unique aspect of this study is it shows how quickly the magma can rise and create either a new volcano or an eruption," said Hicks. "This paper gives us a framework to interpret these seismic events. The amount of magma that moved might have been the greatest amount ever observed."</p><p>The new volcano is three miles in diameter and half a mile from the sea floor. During the formation of the underwater volcano, earthquake activity dropped, and the ground of Mayotte lowered seven inches, though it was hardly noticeable on Mayotte, which is home to about 260,000 people, as <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a> reported.</p><p>"Since the seabed lies 3 kilometres below the water surface, almost nobody noticed the enormous eruption," said Torsten Dahm, study co-author and professor of geophysics and seismology at the University of Potsdam in Germany, as <a href="https://www.cnn.com/2020/01/09/world/seismic-hum-volcano-scn-trnd/index.html" target="_blank">CNN</a> reported. "However, there are still possible hazards for the island of Mayotte today, as the earth's crust above the deep reservoir could continue to collapse, triggering stronger earthquakes."</p>
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A man carries a St. Jude statue from the Inmaculada Concepcion church ruins that was built in 1841 and collapsed after an earthquake hit the island in Guayanilla, Puerto Rico on Jan. 7, 2020. RICARDO ARDUENGO / AFP via Getty Images
A powerful 6.4-magnitude earthquake struck Puerto Rico just before dawn on Tuesday after a week of heavy seismic activity. The early morning quake caused power plants to shut down to protect themselves, leaving the island in a blackout until power is restored later in the day. It also killed at least one person, injured at least eight and collapsed buildings, as the AP reported.
<p>The quake struck at 4:24 a.m. (3:24 a.m. ET), with its epicenter just off Puerto Rico's southern coast, about 6 miles south of Indios town, according to the <a href="https://earthquake.usgs.gov/earthquakes/eventpage/us70006vll" target="_blank">U.S. Geological Survey</a>, as <a href="https://www.cnn.com/2020/01/07/us/puerto-rico-earthquake-tuesday/index.html" target="_blank">CNN</a> reported. The quake triggered three strong aftershocks with preliminary estimates of 5.6, 5.2 and 4.5 magnitude. A bit later a 5.8-magnitude temblor hit closer to Indios at 7:18 a.m., according to the <a href="https://earthquake.usgs.gov/earthquakes/eventpage/us70006vll" target="_blank">U.S. Geological Survey</a>.</p><p>The quake follows a 10-day series of temblors spawned by the grinding of tectonic plates along three faults beneath southern Puerto Rico. Seismologists are unable to predict when the quakes will stop or if they will continue and get stronger, according to the <a href="https://apnews.com/e2ec8e9bd12aea8aff6b240976897389" target="_blank">AP</a>.</p><p>Tuesday's quake was the strongest to hit the island since the temblors began on Dec. 28. It killed Nelson Martínez Guillén, 73, who died after a wall fell on him in the city of Ponce, Mayor Mayita Meléndez said. Another woman had a broken leg after she was pinned under a wall, as <a href="https://www.nytimes.com/2020/01/07/us/puerto-rico-earthquake.html?action=click&module=Latest&pgtype=Homepage" target="_blank">The New York Times</a> reported.</p><p>"The people are scared," Ms. Meléndez said, according to <a href="https://www.nytimes.com/2020/01/07/us/puerto-rico-earthquake.html?action=click&module=Latest&pgtype=Homepage" target="_blank">The New York Times</a>. "There are homes that are totally destroyed."</p><p>She added that the tremors moving through the area have people near the beach living in fear of tsunamis and desperate to flee their homes. However, the United States National Tsunami Warning Center <a href="https://twitter.com/NWS_PTWC/status/1214464205635457024" target="_blank">wrote on Twitter</a> that there was no related tsunami threat.</p><p>"It's not safe," Ms. Melendez said, as <a href="https://www.nytimes.com/2020/01/07/us/puerto-rico-earthquake.html?action=click&module=Latest&pgtype=Homepage" target="_blank">The New York Times</a> reported. "The earth is moving constantly."</p><p>Govenor Wanda Vázquez ordered government offices to remain closed Tuesday except for employees working in an emergency capacity, as the <a href="https://www.miamiherald.com/news/nation-world/world/americas/article239025058.html" target="_blank">Miami Herald</a> reported.</p><p>"It's important for the people of Puerto Rico to remain calm and to secure their lives and property," she said in a statement, according to the <a href="https://www.miamiherald.com/news/nation-world/world/americas/article239025058.html" target="_blank">Miami Herald</a>. "Citizen security is a priority for me, so we are inspecting vulnerable areas and we're taking all the measures necessary to guarantee the safety of Puerto Ricans."</p><p>Local news on Puerto Rico's southern coast reported that several houses collapsed on the coastline and a local highway was shutdown due to rock fall. A nearby elementary school saw its roof cave in and much of the island remained without power on Tuesday morning, according to the <a href="https://www.miamiherald.com/news/nation-world/world/americas/article239025058.html" target="_blank">Miami Herald</a>.</p><p>In Guayanilla municipality, the city's colonial-era church from the 1840s, Immaculate Conception, was destroyed.</p><p>"All that's left is one wall and half of another wall," said Glidden Lopez, the spokesman for Guayanilla municipality, of the beige and pink building that had dominated the main plaza, as the <a href="https://www.miamiherald.com/news/nation-world/world/americas/article239025058.html" target="_blank">Miami Herald</a> reported. "The hospital was damaged and there were several houses that have collapsed but we don't know how many yet."</p><p>Reverend Melvin Díaz Aponte told <a href="https://www.nytimes.com/2020/01/07/us/puerto-rico-earthquake.html?action=click&module=Latest&pgtype=Homepage" target="_blank">The New York Times</a> that both bell towers collapsed, but the nave still stands, though it is fragile.</p><p>"For those who have lived here their whole lives, this is their history," said Father Díaz, as <a href="https://www.nytimes.com/2020/01/07/us/puerto-rico-earthquake.html?action=click&module=Latest&pgtype=Homepage" target="_blank">The New York Times</a> reported. "Their sacraments, their wedding."</p><p>Guayanilla also saw a coastal rock formation that had looked like a rounded window collapse. The rock formation, called Punta Ventana, was a popular tourist draw, as the <a href="https://apnews.com/e2ec8e9bd12aea8aff6b240976897389" target="_blank">AP</a> reported.</p>
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Trending
Victims of climate change protest for climate refugees on the occasion of the Global Climate March on Nov. 28, 2015 in Kutubdia Island, Bangladesh. Zakir Hossain Chowdhury / Barcro / Barcroft Media via Getty Images
Over the past decade, climate-fueled disasters drove over 20 million people a year from their homes, concluded a report released by Oxfam on Monday. The Oxfam study, titled "Forced from Home," was released as two weeks of UN climate negotiations kick-start in Madrid.
<p>It examined the numbers of <a href="http://www.ecowatch.com/tag/climate-refugees">people displaced</a> inside their home countries by climate-fueled disasters between 2008 and 2018, based on government and international agency data, as well as media reports.</p><p>"Today people are seven times more likely to be internally displaced by cyclones, <a href="http://www.ecowatch.com/tag/flooding">floods</a> and <a href="http://www.ecowatch.com/tag/wildfires">wildfires</a> as they are by <a href="http://www.ecowatch.com/tag/earthquakes">earthquakes</a> and volcanic eruptions, and three times more likely than by conflict," the report said.</p><p>While no one is immune, people in <a href="https://www.dw.com/en/building-walls-to-keep-climate-refugees-out/a-48273469" target="_blank">poor countries are most at risk</a>, the NGO said. "People in low and lower-middle income countries such as India, Nigeria and Bolivia are over four times more likely to be displaced by <a href="http://www.ecowatch.com/tag/extreme-weather">extreme weather</a> disasters than people in rich countries such as the United States."</p>
<p>Seven of the top 10 countries with the highest displacement by proportion of their population were <a href="https://www.dw.com/en/climate-change-drives-solomon-islands-people-of-the-sea-ashore/a-40777201" target="_blank">small island developing states, largely in the Pacific</a> and the Caribbean, the report found.</p><p>Asia is the continent most affected, said Oxfam, noting that around 80% of all people displaced over the last decade live there.</p><p>"Our governments are fueling a crisis that is driving millions of women, men and children from their homes and the poorest people in the poorest countries are paying the heaviest price," said Chema Vera, Acting Executive Director of Oxfam International.</p>
<h2>Costs Rising Quickly</h2><p>Overall, the number of <a href="https://www.dw.com/en/coping-with-climate-anxiety-on-a-warming-planet/a-51198686" target="_blank">weather disasters considered extreme</a> grew five-fold over the last decade, researchers said.</p><p>As more people leave their homes as a result of weather disasters, costs — and threats to social stability — are rising quickly for the countries trying to manage that displacement, often with few resources, the report said.</p><p>At the UN climate talks in Madrid, environmental and development groups are pushing to establish a fund to help countries already reeling from climate-enhanced heat waves, droughts, floods and storms made worse by wilder weather and <a href="http://www.ecowatch.com/tag/sea-level-rise" target="_self">rising seas</a>.</p><p>Poor and vulnerable nations are set to receive $100 billion annually from next year to prepare for future impacts, but no concrete provisions exist yet for "loss and damage" already incurred.</p>
<p class=""><em>Reposted with permission from <a href="https://www.dw.com/en/climate-change-forces-20-million-people-to-flee-each-year-says-oxfam/a-51494606" target="_blank">DW</a>.</em></p>From Your Site Articles
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Scientists Discover ‘Stormquakes,’ Small Earthquakes Triggered by Hurricanes and Other Major Storms
17 October 2019
Science
Hurricane Irene caused a stormquake near Little Bahama Bank in 2011. NASA image courtesy Jeff Schmaltz, MODIS Rapid Response, NASA Goddard Space Flight Center
Powerful hurricanes and other storms can actually cause small earthquakes in the ocean, scientists have found.
<p>"We're calling them 'stormquakes,'" study lead author and Florida State University (FSU) assistant professor Wenyuan Fan told <a href="https://news.fsu.edu/news/science-technology/2019/10/15/fsu-research-strong-storms-often-generate-earthquake-like-seismic-activity/" target="_blank">Florida State University News</a>.</p><p>How exactly does it work?</p><p>"During a storm season, hurricanes or nor'easters transfer energy into the ocean as strong ocean waves, and the waves interact with the solid earth producing intense seismic source activity," Fan explained.</p>
<blockquote class="twitter-tweet"><p lang="en" dir="ltr">It's a stormquake! <a href="https://twitter.com/FSU_EOAS?ref_src=twsrc%5Etfw">@FSU_EOAS</a> Assistant Prof. Wenyuan Fan found that hurricanes are often triggering earthquake-like seismic activity in oceans <a href="https://t.co/fkqcnrSHuz">https://t.co/fkqcnrSHuz</a> <a href="https://t.co/dmjW0zS036">pic.twitter.com/dmjW0zS036</a></p>— FSU Research (@FSUResearch) <a href="https://twitter.com/FSUResearch/status/1184106975979855872?ref_src=twsrc%5Etfw">October 15, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
<p>The study, published <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL084217" target="_blank">Monday in Geophysical Research Letters</a>, documented more than 10,000 stormquakes off of Florida, the Gulf of Mexico, New England, Newfoundland, Nova Scotia and British Columbia between 2006 and 2019. The quakes can reach a magnitude of 3.5, but no one has noticed them up until now.</p><p>"This is the last thing you need to worry about," <a href="https://eu.usatoday.com/story/news/nation/2019/10/16/stormquakes-strong-storms-can-generate-earthquakes/3997612002/" target="_blank">Fan told USA Today</a>.</p><p>The researchers themselves weren't setting out to document them when they began their work.</p><p>"It was actually discovered by accident," Fan told the <a href="https://www.tampabay.com/news/environment/2019/10/16/strong-hurricanes-can-produce-stormquakes-offshore-new-study-finds/" target="_blank">Tampa Bay Times</a>.</p><p>Instead, Fan and his colleagues at Woods Hole Oceanographic Institution, Scripps Institution of Oceanography and the U.S. Geological Survey were looking to trace low frequency earthquakes, according to <a href="https://www.nationalgeographic.com/science/2019/10/new-seismic-phenomenon-discovered-named-stormquakes/" target="_blank">National Geographic</a>. They developed a method to track them by piecing together data from different regions, which is when they discovered some unusual seismic events. National Geographic explained why they were so strange:</p><blockquote>Surprisingly, the events were seasonal, never occurring between May and August. Earthquakes that release energy from Earth's shifting crust, however, are usually indifferent to the changing seasons. What's more, the curious quakes radiated from both the east and west coasts of North America. Earthquakes are common out west, rumbling as the earth shifts along a spidery network of fractures in the surface, but the eastern coast largely lacks these quake-generating features.</blockquote><p>Eventually, the researchers realized the small earthquakes took place at the same time as major storms.</p><p>Hurricane Irene, for example, caused stormquakes near Little Bahama Bank while it was a Category 3 storm near Florida, according to the Tampa Bay Times. Hurricane Ike caused stormquakes in the Gulf of Mexico in 2008 and Hurricane Bill caused several off of New England and Nova Scotia in 2009, according to Florida State University News.</p><p>But not every major storm produces stormquakes. Hurricane Sandy, one of the most expensive storms in U.S. history, did not.</p><p>The quakes seem to rely on distinct geological features, National Geographic explained. They occur in regions with broad continental shelves off the coast, which allow the waves from the stormquakes time to build on each other. They also occur in regions with ocean banks, flat underwater hills that channel the waves' energy towards the ground.</p><p>Because of these features, Fan thinks <a href="https://www.ecowatch.com/tag/hurricane-michael" target="_self">Hurricane Michael</a>, which devastated the Florida Panhandle in 2018, probably did cause stormquakes.</p><p>"Given the seafloor topography in the Gulf, I would expect Hurricane Michael to have generated stormquakes offshore," he told the Tampa Bay Times.</p><p>For Fan and his fellow scientists, this paper is just the beginning of attempting to understand this newly identified phenomenon.</p><p>"This paper is laying the foundation for building up new information about how the world works," Wendy Bohon, an earthquake geologist at the Incorporated Research Institutions for Seismology who did not participate in the study, told National Geographic.</p>
<blockquote class="twitter-tweet"><p lang="en" dir="ltr"><a href="https://twitter.com/hashtag/HurricaneLorenzo?src=hash&ref_src=twsrc%5Etfw">#HurricaneLorenzo</a> strengthens to a Category 5 <a href="https://twitter.com/hashtag/storm?src=hash&ref_src=twsrc%5Etfw">#storm</a> and now holds the record for strongest storm recorded this far north and east in the Atlantic. <a href="https://twitter.com/hashtag/hurricane?src=hash&ref_src=twsrc%5Etfw">#hurricane</a> <a href="https://twitter.com/hashtag/disaster?src=hash&ref_src=twsrc%5Etfw">#disaster</a> <a href="https://t.co/4FFBQCl05B">https://t.co/4FFBQCl05B</a></p>— Music for Relief (@MusicForRelief) <a href="https://twitter.com/MusicForRelief/status/1178681565284462592?ref_src=twsrc%5Etfw">September 30, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
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Mining Powers Modern Life, but Can Leave Scarred Lands and Polluted Waters Behind
03 October 2019
Insights + Opinion
The Bingham Canyon open-pit copper mine in Utah has operated since 1903. David Guthrie, CC BY 2.0
By Matthew Ross
Modern society relies on metals like copper, gold and nickel for uses ranging from medicine to electronics. Most of these elements are rare in Earth's crust, so mining them requires displacing vast volumes of dirt and rock. Hard rock mining – so called because it refers to excavating hard minerals, not softer materials like coal or tar sands – generated $600 billion in revenues worldwide in 2017.
<p>The Trump administration has revived several controversial mining proposals that previously were blocked or stalemated. They include the <a href="https://pebblepartnership.com/" target="_blank">Pebble Mine</a> at the headwaters of Alaska's Bristol Bay and leasing around Minnesota's <a href="https://www.mprnews.org/story/2018/09/06/boundary-waters-mining" target="_blank">Boundary Waters Canoe Area Wilderness</a>. It also approved a <a href="https://tucson.com/news/local/rosemont-mine-wins-final-permit-needed-for-construction/article_e3676d00-7297-5429-9854-a8816b75c639.html" target="_blank">large copper mine</a> in southern Arizona, which was subsequently <a href="https://news.azpm.org/p/news-features/2019/8/20/156855-exploring-the-legal-framework-behind-blocking-the-rosemont-mine/" target="_blank">blocked by a federal court ruling</a>.</p><p>I study human-altered landscapes, including areas impacted by mines. Mining operations are major <a href="http://www.ecowatch.com/tag/water" rel="noopener noreferrer">water</a> pollution sources and can cause problems that persist for generations. Their global footprints also directly reshape significant portions of Earth's topography, leaving indelible evidence of human presence.</p>
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<h2>Digging Deep and Wide</h2><p>In most locations, concentrations of copper, gold and other elements are too low to be extracted profitably. But in some spots they occur in seams of mineable, high-concentration minerals called ores. The economically viable concentration of a mineral depends largely on its market price. Gold ore can be viable at concentrations as low as 0.0001%, while copper becomes uneconomic below 0.5%.</p><p>To reach these deposits underground, miners tunnel, dig open pits or scrape through the earth's surface. The choice of technique depends on factors including how consolidated the ore is, the geologic setting and the depth of the ore.</p><p>Deep mines disturb the smallest amount of surface land, but are inherently more dangerous for miners. Far below the earth's surface, crews constantly risk encountering toxic gas fumes or stale air with no life-giving oxygen. Other dangers include <a href="http://www.ecowatch.com/tag/earthquakes" rel="noopener noreferrer">earthquakes</a> and equipment failures. In 2010, 33 Chilean miners spent <a href="https://www.cnn.com/2013/07/13/world/americas/chilean-mine-rescue/index.html" target="_blank">over two months trapped underground</a> in a copper-gold mine after a ramp collapsed, but ultimately were rescued.</p><p>Growing international emphasis on mine safety and changes in technology and ore quality have prompted a shift from deep mining to pit mines or surface mines, which access ores from the open air. Pit mines can be up to three-quarters of a mile deep, but typically cover less than 20 square miles. In contrast, surface mines typically extend less than 1,000 feet into the earth's crust, but can extend over hundreds of square miles.</p>
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Along with metals such as gold, silver and iron, mines also produce materials including sand and gravel, crushed stone and Portland cement. USGS
<h2>Acidic Waters</h2><p>Accessing ore typically involves blowing apart bedrock, removing it from the shaft or pit and storing waste materials nearby after extracting the ore. In these heaps of loose rock, known as spoil piles, previously buried raw minerals are exposed to air or water. Sulfur-rich compounds in the rock react with oxygen and water, producing sulfuric acid, which can lower the pH of nearby streams to levels comparable to lemon juice or vinegar.</p><p>At its worst this process, known as <a href="https://www.colorado.edu/cwest/research/research-themes/water-and-environmental-quality/acid-minerock-drainage" target="_blank">acid mine drainage</a>, can kill most native aquatic life. If acid drainage reaches groundwater, it may persist for decades or centuries and start a cascade of other impacts that impair water quality throughout local river networks.</p><p>When acid mine drainage lowers a stream's pH, other metals can also start to melt out of minerals in spoil piles, mine shafts or adjacent soils, leaching into soil and groundwater that intersects these areas. This creates waters with increased levels of cadmium, copper, lead and other heavy metals, which are harmful to aquatic insects, fish and human health.</p><p>These effects can be transported far downstream and last for generations. Old and abandoned mines around the world have harmed water quality <a href="https://theconversation.com/acid-drainage-the-global-environmental-crisis-youve-never-heard-of-83515" target="_blank">long after mining has ceased</a>. Their impacts can come as long-term slow leakage, or as sudden discharges like the <a href="https://www.denverpost.com/2019/02/20/colorado-mining-industry-water-pollution/" target="_blank">2015 Gold King spill</a> near Silverton, Colorado, which released three million gallons of mine wastewater and debris into the Animas River.</p><p>According to the U.S. Government Accountability Office, there are <a href="https://www.gao.gov/new.items/d11834t.pdf" target="_blank">at least 161,000 abandoned hardrock mining sites</a> in the U.S. West and Alaska. Of these, at least 33,000 have contaminated water supplies or left piles of mine waste contaminated with arsenic behind.</p>
<h2>Altering the Planet's Shape</h2><p>Mining operations have also left thousands of square miles of land altered. In some cases, particularly <a href="https://pubs.acs.org/doi/abs/10.1021/acs.est.5b04532" target="_blank">mountaintop removal mining</a>, entire land forms are <a href="http://mtm-explore.web.duke.edu/" target="_blank">permanently reshaped</a>. For millennia the planet's surface was configured by the slow geologic processes of wind and rain. In contrast, mining alters the very geology, topography, hydrology and ecology of sites within years or decades.</p><p>These earth-moving activities represent the kind of effect that has led many environmental scientists to argue that our planet has entered a new geologic epoch – <a href="https://theconversation.com/the-irony-of-the-anthropocene-people-dominate-a-planet-beyond-our-control-64948" target="_blank">the Anthropocene</a> – where human choices have a greater impact on the earth than purely natural processes. Landscape evolution moves in very slow cycles, so these topographic and geologic impacts may last far longer than mining's effects on water quality. And because geologic processes are slow, scientists don't know how these landscapes will diverge or converge in their future evolution.</p>
<h2>Essential and Scarce</h2><p>Like oil and gas producers, mining companies have to contend with the fact that <a href="https://pubs.usgs.gov/circ/2007/1294/reports/paper9.pdf" target="_blank">the products they seek are scarce</a>, and easily extractable pools have already been tapped, leading to decreases in <a href="https://doi.org/10.3390/resources5040036" target="_blank">ore quality</a>. But demand for these metals continues to grow.</p><p>Rapidly expanding green energy will require extracting vast quantities of <a href="https://theconversation.com/what-are-rare-earths-crucial-elements-in-modern-technology-4-questions-answered-101364" target="_blank">rare earth metals</a> to power <a href="https://www.windpowermonthly.com/article/1519221/rethinking-use-rare-earth-elements" target="_blank">wind turbines</a>, electric vehicle <a href="https://highenergytrading.com/why-we-need-cobalt-rare-earth-minerals-to-power-electric-cars/" target="_blank">batteries</a> and <a href="https://pubs.usgs.gov/circ/1365/" target="_blank">solar panels</a>. Cellphones, computers, camera lenses and other goods also contain these materials.</p>
<blockquote class="twitter-tweet"><p lang="en" dir="ltr">Apple will start using post-industrial <a href="https://twitter.com/hashtag/recycled?src=hash&ref_src=twsrc%5Etfw">#recycled</a> rare earth metals in its iPhones, a company executive told Reuters. <a href="https://t.co/AsrmjbWFQB">https://t.co/AsrmjbWFQB</a> <a href="https://t.co/KxAbfuDTQo">pic.twitter.com/KxAbfuDTQo</a></p>— Resource Recycling (@rrecycling) <a href="https://twitter.com/rrecycling/status/1176952768080355330?ref_src=twsrc%5Etfw">September 25, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
<p>Economic imperatives lead companies to continue to push for new mines, either in the U.S. or abroad, where <a href="http://dx.doi.org/10.1126/science.268.5215.1305" target="_blank">environmental controls may be weaker</a>. And new projects are likely to move more rock, consume more energy and have longer-lasting impacts than those that preceded them.</p><p>Ensuring that mining operations are subject to effective oversight and long-term monitoring, and that companies are held accountable for environmental damages, is a long-term challenge wherever mining takes place. The best way to completely avoid the complications that come from mining more minerals is to reduce consumption of them, make mining processes more efficient and make it more economic to recycle industrial materials and <a href="https://www.recyclingtoday.com/article/rare-earth-metals-recycling/" target="_blank">rare earth metals</a>.</p>
<blockquote class="twitter-tweet"><p lang="en" dir="ltr">Why Global Environmentalists Are Silent on Venezuela’s Mining Crisis <a href="https://t.co/pmntFa7yK0">https://t.co/pmntFa7yK0</a> <a href="https://twitter.com/greenpeaceaustp?ref_src=twsrc%5Etfw">@GreenpeaceAustP</a> <a href="https://twitter.com/wwwfoecouk?ref_src=twsrc%5Etfw">@wwwfoecouk</a></p>— EcoWatch (@EcoWatch) <a href="https://twitter.com/EcoWatch/status/1012259420435337216?ref_src=twsrc%5Etfw">June 28, 2018</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
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<em>Matthew Ross is an assistant professor of water quality at Colorado State University.<br/>
Disclosure statement: Matthew Ross receives funding from the National Science Foundation and NASA.</em>
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<em>Reposted with permission from our media associate <a href="https://theconversation.com/mining-powers-modern-life-but-can-leave-scarred-lands-and-polluted-waters-behind-119453" target="_blank">The Conversation</a>.</em>
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