探花直播 of Cambridge - tectonics
/taxonomy/subjects/tectonics
enScientists 'see' puzzling features deep in Earth鈥檚 interior
/research/news/scientists-see-puzzling-features-deep-in-earths-interior
<div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/flowing-lava.jpg?itok=ulVyQT6-" alt="Etna Volcano Eruption 12 January 2011" title="Etna volcano eruption, 12 January 2011, Credit: gnuckx" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> 探花直播enigmatic area of rock, which is located almost directly beneath the Hawaiian Islands, is one of several ultra-low velocity zones 鈥� so-called because earthquake waves slow to a crawl as they pass through them.</p>
<p> 探花直播<a href="https://www.nature.com/articles/s41467-022-30502-5">research</a>, published in <em>Nature Communications</em>, is the first to reveal the complex internal variability of one of these pockets in detail, shedding light on the landscape of Earth鈥檚 deep interior and the processes operating within it. 聽</p>
<p>鈥淥f all Earth鈥檚 deep interior features, these are the most fascinating and complex. We鈥檝e now got the first solid evidence to show their internal structure - it鈥檚 a real milestone in deep earth seismology,鈥� said lead author Zhi Li, PhD student at Cambridge鈥檚 Department of Earth Sciences.</p>
<p>Earth鈥檚 interior is layered like an onion: at the centre sits the iron-nickel core, surrounded by a thick layer known as the mantle, and on top of that a thin outer shell 鈥� the crust we live on. Although the mantle is solid rock, it is hot enough to flow extremely slowly. These internal convection currents feed heat to the surface, driving the movement of tectonic plates and fuelling volcanic eruptions. 聽</p>
<p>Scientists use seismic waves from earthquakes to 'see' beneath Earth鈥檚 surface 鈥� the echoes and shadows of these waves reveal radar-like images of deep interior topography. But, until recently, 'images'聽of the structures at the core-mantle boundary, an area of key interest for studying our planet鈥檚 internal heat flow, have been grainy and difficult to interpret.</p>
<p> 探花直播researchers used the latest numerical modelling methods to reveal kilometre-scale structures at the core-mantle boundary. According to co-author Dr Kuangdai Leng, who developed the methods while at the 探花直播 of Oxford, 鈥淲e are really pushing the limits of modern high-performance computing for elastodynamic simulations, taking advantage of wave symmetries unnoticed or unused before.鈥� Leng, who is currently based at the Science and Technology Facilities Council, says that this means they can improve the resolution of the images by an order of magnitude compared to previous work.聽</p>
<p> 探花直播researchers observed a 40% reduction in the speed of seismic waves travelling at the base of the ultra-low velocity zone beneath Hawaii. This supports existing proposals that the zone contains much more iron than the surrounding rocks 鈥� meaning it is denser and more sluggish. 鈥淚t鈥檚 possible that this iron-rich material is a remnant of ancient rocks from Earth鈥檚 early history or even that iron might be leaking from the core by an unknown means,鈥� said project lead聽Dr Sanne Cottaar from Cambridge Earth Sciences.</p>
<p> 探花直播research could also help scientists understand what sits beneath and gives rise to volcanic chains like the Hawaiian Islands. Scientists have started to notice a correlation between the location of the descriptively-named hotspot volcanoes, which include Hawaii and Iceland, and the ultra-low velocity zones at the base of the mantle. 探花直播origin of hotspot volcanoes has been debated, but the most popular theory suggests that plume-like structures bring hot mantle material all the way from the core-mantle boundary to the surface.</p>
<p>With images of the ultra-low velocity zone beneath Hawaii now in hand, the team can also gather rare physical evidence from what is likely the root of the plume feeding Hawaii. Their observation of dense, iron-rich rock beneath Hawaii would support surface observations. 鈥淏asalts erupting from Hawaii have anomalous isotope signatures which could either point to either an early-Earth origin or core leaking, it means some of this dense material piled up at the base must be dragged to the surface,鈥� said Cottaar.</p>
<p>More of the core-mantle boundary now needs to be imaged to understand if all surface hotspots have a pocket of dense material at the base. Where and how the core-mantle boundary can be targeted does depend on where earthquakes occur, and where seismometers are installed to record the waves. 聽</p>
<p> 探花直播team鈥檚 observations add to a growing body of evidence that Earth鈥檚 deep interior is just as variable as its surface. 鈥淭hese low-velocity zones are one of the most intricate features we see at extreme depths 鈥� if we expand our search, we are likely to see ever-increasing levels of complexity, both structural and chemical, at the core-mantle boundary,鈥� said Li.</p>
<p>They now plan to apply their techniques to enhance the resolution of imaging of other pockets at the core-mantle boundary, as well as mapping new zones. Eventually they hope to map the geological landscape across the core-mantle boundary and understand its relationship with the dynamics and evolutionary history of our planet.</p>
<p><em><strong>Reference:</strong><br />
Zhi Li, Kuangdai Leng, Jennifer Jenkins, Sanne Cottaar.聽'<a href="https://www.nature.com/articles/s41467-022-30502-5">Kilometer-scale structure on the core鈥搈antle boundary near Hawaii</a>.' Nature Communications (2022), DOI: 10.1038/s41467-022-30502-5</em></p>
</div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>New research led by the 探花直播 of Cambridge is the first to obtain a detailed 'image'聽of an unusual pocket of rock at the boundary layer with Earth鈥檚 core, some three thousand kilometres beneath the surface.</p>
</p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Of all Earth鈥檚 deep interior features, these are the most fascinating and complex</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Zhi Li</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://www.flickr.com/photos/gnuckx/5350977100/in/photolist-99Ra4S-Nf6mBg-eoYhnV-2jgGAGQ-UTX7U5-9QXTH7-UrdR5h-fJUeZo-HbXHM6-eQHWLV-2kKj4zw-9NJFKf-UTX7Ru-7xEgz8-2mfTKk6-cR9Lkd-2ki8TQQ-e16kFX-8MNr64-aqLUmW-bxjHz4-fJx9MP-2jgaZsH-58xyi7-2n9vtqs-7d28DN-253wa93-cR9KHN-fJBHHD-cR9LvE-ov4CWx-9NF1UU-RpKjPA-8gQU1J-UTX7Q7-UTX7KC-nE3Qbt-5W25mK-oeUq7Y-m1g9JM-2jtMqSm-GAF6NF-cR9LeY-2jtNMRK-2iSj1VY-DrwWoo-pN8Rm5-9A9Xh6-9QSqZn-28oFcmZ" target="_blank">gnuckx</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Etna volcano eruption, 12 January 2011</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />
探花直播text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>. Images, including our videos, are Copyright 漏 探花直播 of Cambridge and licensors/contributors as identified.聽 All rights reserved. We make our image and video content available in a number of ways 鈥� as here, on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>
</div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div><div class="field field-name-field-license-type field-type-taxonomy-term-reference field-label-above"><div class="field-label">Licence type: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/imagecredit/public-domain">Public Domain</a></div></div></div>Thu, 19 May 2022 09:00:00 +0000cmm201232241 at Earth's interior is swallowing up more carbon than thought
/research/news/earths-interior-is-swallowing-up-more-carbon-than-thought
<div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/news/volcanoaerial.jpg?itok=dIQffxNm" alt="Alaska鈥檚 Pavlof Volcano: NASA鈥檚 View from Space" title="Alaska鈥檚 Pavlof Volcano: NASA鈥檚 View from Space, Credit: NASA Goddard Space Flight Center" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>They found that the carbon drawn into Earth鈥檚 interior at subduction zones - where tectonic plates collide and dive into Earth鈥檚 interior - tends to stay locked away at depth, rather than resurfacing in the form of volcanic emissions.</p>
<p>Their findings, published in <a href="https://www.nature.com/articles/s41467-021-24533-7">Nature Communications</a>, suggest that only about a third of the carbon recycled beneath volcanic chains returns to the surface via recycling, in contrast to previous theories that what goes down mostly comes back up.</p>
<p>One of the solutions to tackle climate change is to find ways to reduce the amount of CO<sub>2</sub> in Earth鈥檚 atmosphere. By studying how carbon behaves in the deep Earth, which houses the majority of our planet鈥檚 carbon, scientists can better understand the entire lifecycle of carbon on Earth, and how it flows between the atmosphere, oceans and life at the surface.</p>
<p> 探花直播best-understood parts of the carbon cycle are at or near Earth鈥檚 surface, but deep carbon stores play a key role in maintaining the habitability of our planet by regulating atmospheric CO<sub>2</sub> levels. 鈥淲e currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth鈥檚 interior carbon stores, which cycle carbon over millions of years,鈥� said lead author Stefan Farsang, who conducted the research while聽a PhD student at Cambridge's Department of聽Earth Sciences.</p>
<p>There are a number of ways for carbon to be released back to the atmosphere (as CO<sub>2</sub>) but there is only one path in which it can return to the Earth鈥檚 interior: via plate subduction. Here, surface carbon, for instance in the form of seashells and micro-organisms which have locked atmospheric CO<sub>2</sub> into their shells, is channelled into Earth鈥檚 interior. Scientists had thought that much of this carbon was then returned to the atmosphere as CO<sub>2</sub> via emissions from volcanoes. But the new study reveals that chemical reactions taking place in rocks swallowed up at subduction zones trap carbon and send it deeper into Earth鈥檚 interior - stopping some of it coming back to Earth鈥檚 surface.</p>
<p> 探花直播team conducted a series of experiments at the European Synchrotron Radiation Facility, 鈥� 探花直播ESRF has聽world-leading facilities and the expertise that we needed to get our results,鈥� said co-author Simon Redfern, Dean of the College of Science at NTU Singapore, 鈥� 探花直播facility can measure very low concentrations of these metals at the high pressure and temperature conditions of interest to us.鈥� To replicate the high pressures and temperatures of subductions zones, they used a heated 鈥榙iamond anvil鈥�, in which extreme pressures are achieved by pressing two tiny diamond anvils against the sample.</p>
<p> 探花直播work supports growing evidence that carbonate rocks, which have the same chemical makeup as chalk, become less calcium-rich and more magnesium-rich when channelled deeper into the mantle. This chemical transformation makes carbonate less soluble 鈥� meaning it doesn鈥檛 get drawn into the fluids that supply volcanoes. Instead, the majority of the carbonate sinks deeper into the mantle where it may eventually become diamond.</p>
<p>鈥淭here is still a lot of research to be done in this field,鈥澛爏aid聽Farsang.聽鈥淚n the future, we aim to refine our estimates by studying carbonate solubility in a wider temperature, pressure range and in several fluid compositions.鈥�</p>
<p> 探花直播findings are also important for understanding the role of carbonate formation in our climate system more generally. 鈥淥ur results show that these minerals are very stable and can certainly lock up CO<sub>2</sub> from the atmosphere into solid mineral forms that could result in negative emissions,鈥� said Redfern. 探花直播team have been looking into the use of similar methods for carbon capture, which moves atmospheric CO<sub>2</sub> into storage in rocks and the oceans.</p>
<p>鈥淭hese results will also help us understand better ways to lock carbon into the solid Earth, out of the atmosphere. If we can accelerate this process faster than nature handles it, it could prove a route to help solve the climate crisis,鈥� said Redfern.</p>
<p>聽</p>
<p><em><strong>Reference:</strong><br />
Farsang, S, Louvel, M, Zhao, C聽et al.聽<a href="https://www.nature.com/articles/s41467-021-24533-7">Deep carbon cycle constrained by carbonate solubility</a>.聽Nature Communications (2021). DOI: 10.1038/s41467-021-24533-7</em></p>
<p><em>Adapted from a news release by the聽ESRF</em></p>
</div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Scientists from Cambridge 探花直播 and NTU Singapore have found that slow-motion collisions of tectonic plates drag more carbon into Earth鈥檚 interior than previously thought.</p>
</p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">We currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth鈥檚 interior carbon stores, which cycle carbon over millions of years</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Stefan Farsang</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://www.flickr.com/photos/gsfc/8815681798" target="_blank">NASA Goddard Space Flight Center</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Alaska鈥檚 Pavlof Volcano: NASA鈥檚 View from Space</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />
探花直播text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>. Images, including our videos, are Copyright 漏 探花直播 of Cambridge and licensors/contributors as identified.聽 All rights reserved. We make our image and video content available in a number of ways 鈥� as here, on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>
</div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div><div class="field field-name-field-license-type field-type-taxonomy-term-reference field-label-above"><div class="field-label">Licence type: </div><div class="field-items"><div class="field-item even"><a href="/taxonomy/imagecredit/attribution">Attribution</a></div></div></div>Mon, 26 Jul 2021 09:59:43 +0000cmm201225621 at Earthquake rocks Afghanistan and Pakistan 鈥� an area prone to magnitude 7 quakes
/research/discussion/earthquake-rocks-afghanistan-and-pakistan-an-area-prone-to-magnitude-7-quakes
<div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/discussion/151027hindu-kush-range.png?itok=TgeAwu1i" alt="Topography of Hindu Kush." title="Topography of Hindu Kush., Credit: Wikimedia Commons" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>A devastating earthquake struck the <a href="https://www.icimod.org/who-we-are/staff/strategic-cooperation-regional/">Hindu Kush</a> region of north-east Afghanistan just after lunchtime on October 26, rocking communities as far away as Tajikistan, Pakistan and even India. A devastating earthquake struck the <a href="https://www.icimod.org/who-we-are/staff/strategic-cooperation-regional/">Hindu Kush</a> region of north-east Afghanistan just after lunchtime on October 26, rocking communities as far away as Tajikistan, Pakistan and even India.</p>
<p> 探花直播strong quake, estimated at magnitude 7.5 by the US Geological Survey (USGS), had its origins more than 200km deep beneath Earth鈥檚 surface, and was felt as strong shaking across a very wide area. Casualties have been reported from across the region, with widespread landslips causing potential further damage to infrastructure.</p>
<p>So far it has been reported that <a href="https://www.theguardian.com/world/2015/oct/26/earthquake-of-77-magnitude-strikes-in-northern-pakistan">150 people have died</a>, but this number is likely to rise.</p>
<p> 探花直播quake is the second large shake to hit the Alpine-Himalayan earthquake belt this year, following the one that <a href="https://theconversation.com/nepal-shows-its-vulnerability-after-devastating-earthquake-40799">devastated Nepal</a> in April. A region stretching from the Mediterranean through Anatolia, Iran and Central Asia into the mountains of South-East Asia, the Alpine-Himalayan belt is the home of around a fifth of the world鈥檚 largest earthquakes.</p>
<p>聽</p>
<figure class="align-right"><img alt="" src="https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/99708/width237/image-20151026-18424-jdfvex.png" /><figcaption><span class="caption">Tectonic plates collide.</span> <span class="attribution"><span class="source">LennyWikipedia~commonswiki</span>, <a class="license" href="https://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>聽</p>
<p> 探花直播earthquake was driven by collision between the Eurasian tectonic plate to the north and the Indian plate to the south. 探花直播area marks the scar of the closure of an ancient ocean, the <a href="https://www.uwgb.edu/dutchs/platetec/closteth.htm/">Thethys</a>, which once separated the continents of Gondwana, including most of the landmasses in today鈥檚 southern hemisphere, and Laurasia, made up of most of the countries that are today in the northern hemisphere.</p>
<p> 探花直播Hindu Kush has experienced many such earthquakes before today, and this latest appears to follow closely the pattern of those of the past. <a href="https://earthquake.usgs.gov/earthquakes/eventpage/us10003re5">Preliminary analysis</a> by the USGS indicates that it was caused by a deep fault in which rocks thrust past each other instantaneously. They point out that seven earthquakes of magnitude 7 or more <a href="https://earthquake.usgs.gov/earthquakes/eventpage/us10003re5">have hit within 250km of the current earthquake</a> over the past century. Most recently the magnitude 7.4 earthquake, some 20km west of the latest event, <a href="https://edition.cnn.com/2013/07/05/world/earthquakes-fast-facts/">killed over 150 people</a> in March 2002.</p>
<p>This type of deep fault, a near-vertical a thrust fault, is a process that has previously been associated with the tearing off of sections of ancient ocean floor sinking into the Earth鈥檚 mantle beneath today鈥檚 continent. Researchers have <a href="https://www.nature.com/articles/ngeo132">previously suggested</a> that earthquakes in the Hindu Kush can be caused by the break off of strips of such slabs, stretching and tearing free, on geological time scales, as they fall deep into the mantle.</p>
<p>Whatever the geological triggers for the quake, grieving communities will now be gathering themselves together and guarding against the inevitable aftershocks. With increased understanding of the risks that Earth poses along this seismic belt, it is important to be aware and prepare for future large earthquakes. If buildings are not to be destroyed time and again, it is important to adopt and adhere to construction and planning codes. A key step in promoting legal enforcement is educating the community about the risks, as well as how to respond as safely as possible during an earthquake.</p>
<p>Efforts such as the 鈥�<a href="http://ewf.nerc.ac.uk/">Earthquakes without Frontiers</a>鈥� continue to <a href="/research/features/earthquakes-without-frontiers">highlight the risks of earthquakes</a>, and have drawn attention to the tectonic forces that stand poised to strike along Tethys鈥� former shores.</p>
<p><em><strong><span><a href="https://theconversation.com/profiles/simon-redfern-95767">Simon Redfern</a>, Professor in Earth Sciences, <a href="https://theconversation.com/institutions/university-of-cambridge-1283"> 探花直播 of Cambridge</a></span></strong></em></p>
<p><em><strong>This article was originally published on <a href="https://theconversation.com/"> 探花直播Conversation</a>. Read the <a href="https://theconversation.com/earthquake-rocks-afghanistan-and-pakistan-an-area-prone-to-magnitude-7-quakes-49783">original article</a>.</strong></em></p>
<p><em> 探花直播opinions expressed in this article are those of the individual author(s) and do not represent the views of the 探花直播 of Cambridge.</em></p>
</div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Professor Simon Redfern (Department of Earth Sciences) discusses the devastating earthquake that struck Afghanistan on October 26 and the geological triggers that caused it.</p>
</p></div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://commons.wikimedia.org/wiki/File:Hindu-Kush-Range.png" target="_blank">Wikimedia Commons</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Topography of Hindu Kush.</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br />
探花直播text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright 漏 探花直播 of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways 鈥� as here, on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/social-media/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>
<p>For image use please see separate credits above.</p></div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div>Tue, 27 Oct 2015 12:35:31 +0000Anonymous161092 at Earthquakes without frontiers
/research/features/earthquakes-without-frontiers
<div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/features/151026-earthquakes.png?itok=WDPHdUkQ" alt=" 探花直播city of Muzafarabad, Pakistan lays in ruins after the 2005 Kashmir earthquake that hit the region." title=" 探花直播city of Muzafarabad, Pakistan lays in ruins after the 2005 Kashmir earthquake that hit the region., Credit: Timothy Smith, U.S. Navy" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> 探花直播Ganges is India鈥檚 most iconic river, flowing from the Himalaya to the Bay of Bengal, and its massive river basin is one of the most fertile and densely populated regions in the world. 探花直播Ganges flows through 29 cities with a population over 100,000, 23 cities with a population between 50,000 and 100,000, and close to 50 towns.</p>
<p>But someday 鈥� perhaps tomorrow or perhaps in 100 years 鈥� a massive earthquake will hit the region, and the consequences could be catastrophic: as many as a million lives in the Ganges river basin could be at risk, primarily because buildings have not been constructed to be earthquake resilient, despite the fact that the relevant building codes are in place.</p>
<p>Of course, earthquakes don鈥檛 respect borders, and India is not alone in being at risk due to poorly constructed buildings. Northern India lies in the Alpine鈥揌imalayan earthquake belt, which stretches from the Mediterranean to the Pacific. It is the second-most seismically active region in the world, and responsible for around 20% of the world鈥檚 largest earthquakes. 探花直播belt is being created by ongoing plate tectonics: as the African, Arabian and Indian plates continue to move northwards, they collide with the Eurasian plate.</p>
<p> 探花直播earthquake belt includes the most famous of the great trade routes, the Silk Road, which follows the edges of deserts and mountains, and high plateaus like Tibet. 探花直播landscape of the Silk Road has been shaped by earthquakes over millions of years: forcing mountains upwards and making life in the desert possible by controlling where water comes to the surface.</p>
<p>As the earthquake faults grind rocks together they make an impermeable clay, which often forces water to the surface along spring lines, determining where people live. To the casual observer, it seems as if the major earthquakes in this part of the world often seem to 鈥榯arget鈥� towns and cities but, in reality, people are often simply living where the water is, which is also where earthquakes happen.</p>
<p>Between 2 and 2.5 million people have died in earthquakes since 1900. Approximately two thirds of those deaths occurred in earthquakes in the continental interiors 鈥� places like northern India. Over that time, advances in the scientific understanding of earthquakes have been translated into impressive resilience in places where the hazard is well understood, which are mainly on the edges of the oceans. Comparable advances have not, however, taken place in most parts of the continental interiors, where the hazard is still much less well identified and poorly understood.</p>
<p>鈥淓arthquake science has progressed so that we鈥檙e now much better at recognising the signals in the landscape that tell us whether a particular place is dangerous,鈥� says Professor James Jackson, Head of Cambridge鈥檚 Department of Earth Sciences. 鈥淲e can鈥檛 tell you exactly when an earthquake is going to happen, but we can say it will happen, not least because it鈥檚 happened before. If it鈥檚 happened before, it will happen again. What we can do, however, is to understand earthquakes better and use that knowledge to help make buildings safer.鈥�</p>
<p>Four years ago, with funding from the Natural Environment Research Council, Jackson and colleagues from other universities in the UK established Earthquakes Without Frontiers (EWF), an international partnership bringing together earthquake scientists from across the great earthquake belt, from China to Italy, in order to share expertise. 鈥淏ut it soon became clear that the project was about much more than earthquake science, and the real issue was how to translate science into effective policy, which requires an understanding of the social context in which people live,鈥� says Jackson.</p>
<p>With additional funding from the Economic and Social Research Council, EWF expanded to include social science and policy dimensions. 探花直播project, which runs until 2017, has three overarching objectives: to increase knowledge of earthquake hazards across the region; to establish greater resiliency against these hazards; and to establish a well-networked interdisciplinary partnership to support local earthquake scientists. Within Asia, there are more than 50 national level stakeholders who are working with EWF on earthquake risk reduction.</p>
<p>Across much of the earthquake belt, people live in large cities, mostly in poorly built apartment blocks and buildings that have not been designed to withstand earthquakes. Large cities such as Tehran, Almaty and Bishkek have all been destroyed multiple times by earthquakes, and it鈥檚 only a matter of time before the next one hits. 探花直播problem that EWF faces is convincing the public and policy makers of the importance of making towns and cities more earthquake resilient.</p>
<p>鈥淚n these big cities, everyday life is difficult enough: they鈥檙e very congested, they have huge problems with traffic, air quality, water quality, food supply and poverty,鈥� explains Jackson. 鈥淎nd quite understandably, the risk of an earthquake seems quite remote compared to daily worries. But that doesn鈥檛 make the threat go away.鈥�</p>
<p>鈥淲e face two main problems: the first is that there is a lack of awareness of the fact that seismologists cannot predict earthquakes 鈥� it鈥檚 just not something we are able to do or will be able to do,鈥� says Dr Supriyo Mitra of the Indian Institute of Science Education and Research Kolkata. Mitra obtained his PhD at Cambridge, and is now one of the key Indian academic collaborators on the project, primarily working in Indian-administered Kashmir. 鈥� 探花直播other problem is that there is a lot of resistance to making buildings safe. It is an additional cost, but it鈥檚 a necessity and we need to get that across to people.鈥�</p>
<p>Perhaps the most important change that can be made to increase earthquake resilience in these areas is the enforcement of building codes. 探花直播building codes in Los Angeles and Tehran are similar, but the difference is that in Los Angeles, most buildings are constructed according to those codes, while in Tehran most are not, so as a result, Los Angeles is highly resilient to earthquakes, while Tehran remains very vulnerable.</p>
<p>鈥淓nforcement comes not just from legal enforcement, but education,鈥� adds Jackson. 鈥淧eople are really starting to realise that this is important. And once you educate the public, it rises up the agenda because the public insists that it does.</p>
<p>鈥淭here are going to be around a billion new homes built across Asia over the next 10 years 鈥� let鈥檚 build them so they are safe.鈥�</p>
</div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p> 探花直播Alpine鈥揌imalayan belt, which stretches from the Mediterranean to the Pacific, is one of the world鈥檚 most seismically active regions. Now, a combination of earth science, social science and education is being used to help the region become more resilient to earthquakes, protecting lives and property.</p>
</p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">We can鈥檛 tell you exactly when an earthquake is going to happen, but we can say it will happen, not least because it鈥檚 happened before. If it鈥檚 happened before, it will happen again.</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">James Jackson</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://commons.wikimedia.org/wiki/File:Muzaffarabad_-_2005_Kashmir_earthquake.jpg" target="_blank">Timothy Smith, U.S. Navy</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even"> 探花直播city of Muzafarabad, Pakistan lays in ruins after the 2005 Kashmir earthquake that hit the region.</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />
探花直播text in this work is licensed under a <a href="https://creativecommons.org/licenses/by/4.0/" rel="license">Creative Commons Attribution 4.0 International License</a>. For image use please see separate credits above.</p>
</div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div>Mon, 26 Oct 2015 13:31:11 +0000sc604160932 at