tag:theconversation.com,2011:/fr/topics/mineralogy-10598/articlesMineralogy – The Conversation2023-11-08T13:53:29Ztag:theconversation.com,2011:article/2134792023-11-08T13:53:29Z2023-11-08T13:53:29ZTurkana stone beads tell a story of herder life in a drying east Africa 5,000 years ago<p>On the shores of Lake Turkana in east Africa, about 5,000 to 4,000 years ago, pastoralists buried their dead in communal cemeteries that were marked by stone circles and pillars. <a href="https://doi.org/10.1073/pnas.1721975115">The north-west Kenya “pillar sites”</a> were built around the same time as Stonehenge in the UK. But these places have a different story to tell: about how mortuary traditions reflect people’s environments, behaviours and reactions to change.</p>
<p>The burial sites appeared at a time of major <a href="https://www.sciencedirect.com/science/article/pii/S027737912200021X">environmental</a> and economic <a href="https://www.sciencedirect.com/science/article/pii/S0012825217303331">change</a> in the region. The Sahara, which received enough rainfall 9,000-7,000 years ago to sustain populations of fisher-hunter-gatherers and pastoralists, was <a href="https://pastglobalchanges.org/publications/pages-magazines/pages-magazine/7413">drying</a>, causing groups of people to move east and south. Even in eastern Africa, lake levels were dropping dramatically; grassy plains were expanding. Around Lake Turkana, people began herding animals in addition to fishing and foraging. </p>
<p>At several of the pillar sites around Lake Turkana, archaeologists have found that hundreds of people were <a href="https://link.springer.com/article/10.1007/s12520-019-00914-4">ceremonially interred</a> under large, circular platform mounds. Many of those individuals were found wearing remarkable colourful stone beads, some as part of necklaces, bracelets, earrings, and other jewellery worn, for example, around the waist. These beautiful personal ornaments include blue-green amazonite, soft pink zeolite, deep red chalcedony, purple fluorite and green talc, among other minerals and rocks.</p>
<p>I study relationships between humans and their environments, especially at times of major economic transformations, using scientific techniques applied to archaeology. I recently led a team of experts in geology and archaeology of the region to conduct the first comprehensive mineralogical <a href="https://www.tandfonline.com/doi/full/10.1080/00934690.2023.2232703">analysis</a> of the Turkana stone beads. </p>
<p>The focus of our study was to discover what types of minerals and rocks the early herders had used to make adornments, and where these materials came from. </p>
<p>This kind of information can tell archaeologists about the role of artefacts in the society that used them.</p>
<h2>Wearing beads</h2>
<p>Humans have been making and wearing beads for over <a href="https://www.science.org/doi/10.1126/sciadv.abi8620">140,000 years</a>. Beads are one of the oldest forms of symbolism and are often used as <a href="https://theconversation.com/the-tiny-ostrich-eggshell-beads-that-tell-the-story-of-africas-past-128577">adornment</a> in a culture. Wearing something on your body is an expressive choice that can have many meanings, such as protection, acknowledgement of friendships and bonds, status or role in society. Personal ornaments like beads may indicate a common cultural understanding. </p>
<p>Analysis of <a href="https://theconversation.com/what-excavated-beads-tell-us-about-the-when-and-where-of-human-evolution-53695">beads in archaeological sites</a> has shown that we can learn many things from them. </p>
<p>At the Turkana pillar sites, the stone bead tradition was clearly important, partly because of the number of beads found accompanying burials, and partly because the practice persisted for hundreds of years. </p>
<p>Knowing the range of materials helps us understand landscape use in the past: where people were buried, where they watered their animals, seasonal movements for grazing, special yearly trips to significant places and other movements. Pastoralists recorded or marked their worlds by what they left behind and what they took with them. Patterns in the composition of the bead collections may indicate there was communication and exchange of objects across the region.</p>
<h2>Sorting the stone beads</h2>
<p>Of the six pillar sites that have been excavated by archaeologists, three have yielded substantial assemblages of stone beads: Lothagam North, Manemanya and Jarigole. Our team began by sorting the stone beads by site, and by their mineral and rock types.</p>
<p>Our study identified the mineral characteristics of 806 stone beads. We looked at properties like <a href="https://www.britannica.com/science/specific-gravity">specific gravity</a>, crystal and molecular structure, and the characteristic emissions that are particular to certain minerals. </p>
<p>What we found was a strikingly diverse set of beads that varied by site. The visual characteristics of some of the beads – colour, lustre and so on – may have made them particularly valuable or had a special meaning economically, socially, spiritually or symbolically. Their source and workability may also have given them a certain value. </p>
<p>Pink zeolites and turquoise amazonites were the most common stone beads at the site of Lothagam North, comprising over three-quarters of the assemblage. This was very similar to the site of Jarigole, located across the lake. The sites are hundreds of kilometres apart, with Lake Turkana in between – suggesting a cultural connection between them.</p>
<p>In contrast, the kinds of beads at Manemanya were different: mostly softer and paler pink and off-white calcite beads that were quite large. Further, while at Lothagam North there often were just a few beads found with any individual, one person at Manemanya was buried with over 300 stone beads and over 10,000 ostrich eggshell beads. </p>
<p>This suggests that although having stone beads was a commonality across the sites, distinctions – and distinct meanings for different people – did exist. </p>
<h2>Sourcing stones</h2>
<p>We also wanted to know whether the beads were produced from local sources (within a few days’ walk) or acquired through long-distance journeys or trade. Sourcing allows us to partially reconstruct how the earliest pastoralists moved around the landscape during the year.</p>
<p>A survey of the areas west of Lake Turkana and a search of the published literature on the geology of the region identified places where these materials might have come from.</p>
<p>There are possible sources for most of these materials within about 150km of the pillar sites. Limestone rocks may have been procured easily near the lake. Some of the tougher materials, like the chalcedonies, could have been carried to the lake area by rivers, to be picked up perhaps by someone watering cattle or fetching water from a stream. Other minerals come from a specific source. The variety of bead types demonstrates that people knew their landscape well.</p>
<p>Sometimes, they went out of their way to get certain minerals, or perhaps traded for them. The closest known sources for amazonite and fluorite are, respectively, 225 km, in southern Ethiopia; and 350 km, near the modern city of Eldoret, Kenya. </p>
<p>These suggest that bead making was not just a casual affair; material selection was intentional.</p>
<h2>Local landscapes</h2>
<p>Early herders in the Turkana Basin obtained materials from both local and distant places, and shaped them into personal adornments. These stone beads were placed with the dead, in numbers and combinations that differed by individual and place. We don’t yet fully know what they meant – but future research in the Turkana Basin will continue to explore the lives and legacies of these pioneering herders as they negotiated new environmental and social landscapes.</p>
<p><em>Edits and comments for this article were provided by Late Prehistory of West Turkana project co-directors Drs. Elizabeth Hildebrand and Katherine Grillo, project minerologist Mark Helper, and Emmanuel Ndiema, who helped lead the sourcing study.</em></p><img src="https://counter.theconversation.com/content/213479/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Funding for Klehm's research on the pillar site stone beads was provided by the Wenner-Gren Foundation.</span></em></p>Mineralogical analysis of 5,000-year-old stone beads from Turkana, Kenya suggest a novel mortuary tradition by early pastoralists.Carla Klehm, Research Assistant Professor, Center for Advanced Spatial Technologies, University of ArkansasLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2082852023-06-22T10:22:46Z2023-06-22T10:22:46ZGrattan on Friday: Labor’s ‘Godfather’ seeks deal on electoral reform – but some fear changes could disadvantage community candidates<p>Special Minister of State Don Farrell, who’s also minister for trade and tourism and the government’s deputy leader in the Senate, is a numbers man from way back. </p>
<p>A powerbroker of the right, in 2012 Farrell (only a parliamentary secretary at the time) had the numbers to be placed top of the South Australian Senate ticket, relegating the left’s Penny Wong, who was a senior minister, to the second spot for the 2013 election.</p>
<p>Sometimes, however, the numbers don’t prevail. Amid the ensuing controversy, Farrell stepped down to second place. </p>
<p>As a result he lost his seat at the 2013 election. He turned his hand to establishing a vineyard, before being returned at the 2016 election and becoming deputy opposition leader in the Senate. Then he had to cede that position to Kristina Keneally after the 2019 election. </p>
<p>Farrell and Anthony Albanese were long-time factional opponents. But under Albanese’s government, Farrell is prospering. With the thaw in China-Australia relations, it’s a very good time to be trade minister. </p>
<p>Now Farrell is set to wrangle sweeping changes to the donation and spending rules for federal elections. Those changes have the potential to affect parliamentary numbers in future elections. </p>
<p>This week the Joint Standing Committee on Electoral Matters (JSCEM) recommended broad reforms: a drastic lowering of the threshold for disclosing donations, and “real time” disclosure; caps on donations and spending, including for “third parties” (such as Climate 200, founded by Simon Holmes à Court) and associated entities (primarily bodies raising money for parties); and increased public funding for elections. The committee also said there should be legislation for truth in advertising. </p>
<p>The recommendations were made in the <a href="https://www.aph.gov.au/Parliamentary_Business/Committees/Joint/Electoral_Matters/2022federalelection/Interim_Report">committee’s majority report</a>, with the Coalition members dissenting on key issues. JSCEM didn’t spell out fine detail, and its final report won’t come until late in the year. </p>
<p>Farrell is not waiting for JSCEM’s last word. Unsurprisingly, the recommendations from the Labor-dominated committee are in line with Labor’s policy, and Farrell is already off and running. He’ll have negotiations with the players over the next few months, although legislation would wait until after the final report. He says he wants to get consensus if possible – a challenge, given the opposition’s position, but not necessarily out of the question. </p>
<p>A central aim of the proposals is to reduce the power of “big money” to influence elections. </p>
<p>“Big money” donations from business and unions have long been a concern. Clive Palmer elevated this to a new level with his spending in the 2019 and 2022 elections. Palmer spent $83.6 million in the 2019 campaign. In 2022, he spent an extraordinary $117 million (albeit to minimal effect – only one senator from his United Australia Party was elected, and he had little influence on the overall result). </p>
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<a href="https://theconversation.com/sweeping-election-donation-and-spending-reforms-recommended-by-parliamentary-committee-208030">Sweeping election donation and spending reforms recommended by parliamentary committee</a>
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<p>Few would defend the Palmer cash splash as being appropriate in a good electoral system. </p>
<p>But dig deeper and the spending argument becomes a lot more complicated, with the pros and cons of caps nuanced, and decisions requiring fine judgments. </p>
<p>Teals elected in 2022 had expensive campaigns. Allegra Spender (Wentworth) spent more than $2 million, as did Monique Ryan in Kooyong. Without large amounts of money, some of the teal candidates could have struggled to get the name recognition that helped them win. Without Climate 200, a number of candidates would have had substantially less resources.</p>
<p>The teals might be dubbed the high end of the wider “community candidate” movement, which has gained increasing public support and given voters more choice and thus, arguably, more agency in our democracy. </p>
<p>Electoral reform is all about having a “level playing field”. But many factors influence that playing field, including whether the person is already on the field as a sitting member (or has advantaged access, as a candidate backed by an established political party). </p>
<p>Kate Chaney, a teal who holds the Western Australian seat of Curtin, was a member of JSCEM. In her “additional comments” in the report she says, while agreeing with the principle of curbing “big money”, it’s important the system is open to new entrants.</p>
<p>“Caps” need to be “structured to recognise the additional barriers to entry faced by independents or new entrants”, Chaney argues. “Donation caps must not be set too low […] new entrants are dependent on ‘seed capital’ to reach critical mass in campaign viability.” </p>
<p>Chaney is also hesitant about extra public funding, saying it’s “unhelpful” to replace private “big money” with “state dependency/taxpayer funding”. “State dependency is the opposite of community funding and engagement which should be promoted by changes to our system.” </p>
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<a href="https://theconversation.com/australians-feelings-towards-china-are-thawing-but-suspicion-remains-high-lowy-2023-poll-208103">Australians' feelings towards China are thawing but suspicion remains high: Lowy 2023 poll</a>
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<p>Holmes à Court claims “poorly implemented” caps would actually weaken democracy rather than enhance it. He says the changes that have been made in Victoria and NSW “give the majors a free ride and effectively handicap outside competition”.</p>
<p>While superficially the odds might seem against an agreement between government and opposition, they both stand to gain from pushing towards it (there would be less chance on truth-in-advertising legislation). The two main parties share the serious problem of a falling primary vote, which they want to protect from further erosion. </p>
<p>Certainly, Holmes à Court has fears. “We wholeheartedly support reform if it’s fair, but we should all be suspicious because major parties have a track record of changing election laws to rig the game for their own benefit,” he tells The Conversation.</p>
<p>“Let’s be frank, Labor would like to see the back of Palmer, and the Coalition would like to kill the independents movement.</p>
<p>"While the Libs are saying they oppose Labor’s changes, ultimately they have only two ways to get back into government: change their culture, or change the rules, the latter being much easier.</p>
<p>"The devil is very much in the details. If we’re not careful it’ll be a big step backwards for Australia’s recently reinvigorated democracy.”</p>
<p>One person’s “consensus” can be another’s dirty deal, it seems. Different players have distinct interests. </p>
<p>Before the last election Graham Richardson, himself a former Labor right-wing powerbroker, <a href="https://www.theaustralian.com.au/commentary/labors-godfather-a-guardian-of-common-sense/news-story/70ae72981abfe30d99f6528a721658c3">wrote</a> of Farrell, “the Godfather brings traditional common sense to Labor’s decision-making processes”. </p>
<p>Principle, pragmatism and common sense will all be needed to find the combination of reforms most attuned to reflecting the country’s democratic will and giving voters maximum agency. <a href="https://theconversation.com/politics-with-michelle-grattan-special-minister-of-state-don-farrell-wants-donation-and-spending-caps-for-next-election-208107">Farrell says</a> it’s a matter of finding the right balance, between restricting the ability to “buy” elections and finding ways to improve access to democracy. “My job in the next six months […] will be to try and find that balance.”</p><img src="https://counter.theconversation.com/content/208285/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michelle Grattan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Farrell and Albanese were long-time factional opponents. But under Albanese’s government, Farrell is prospering. With the thaw in China-Australia relations, it’s a very good time to be trade minister.Michelle Grattan, Professorial Fellow, University of CanberraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1950152022-11-21T11:36:24Z2022-11-21T11:36:24ZGroundbreaking studies of Earth’s churning oceans recognised at Australia’s most prestigious science prizes this year<figure><img src="https://images.theconversation.com/files/496396/original/file-20221121-14-7m0lqx.jpg?ixlib=rb-1.1.0&rect=609%2C0%2C6173%2C4311&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=3827">Greg Shirah/NASA Scientific Visualisation Studio</a></span></figcaption></figure><p>This year, Australia’s prestigious Prime Minister’s Prize for Science has been awarded to a physical oceanographer whose work has had a “transformative impact” on our understanding of Earth’s oceans.</p>
<p>Professor Trevor McDougall AC from the University of New South Wales has made major contributions to unveiling the fundamental physics of the ocean.</p>
<p>During his illustrious career, McDougall has discovered previously unknown ocean mixing processes – the turbulent ways seawater churns and <a href="https://www.uib.no/en/rg/fysos/53334/ocean-mixing">irreversibly changes</a> under various conditions.</p>
<p>His discoveries have improved climate models, allowing us to better predict our planet’s fast-changing future.</p>
<p>“The ocean is notoriously difficult to observe; we know more about the surface of the Moon than we do about the seafloor,” McDougall said.</p>
<p>“We study the ocean because it transports a lot of heat from the equatorial regions towards the poles and also because it acts as the thermal flywheel of the climate system.” </p>
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<a href="https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A smiling older gentleman looking at the camera with the sea in the background" src="https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496389/original/file-20221121-12-1clq6g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Trevor McDougall is a world-leading researcher in ocean thermodynamics.</span>
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<p>A world-leading authority on ocean mixing, McDougall was recognised for his many contributions, including a redefinition of the thermodynamic description of seawater. The latter <a href="https://csiropedia.csiro.au/science-adopts-a-new-definition-of-seawater/">was accepted by</a> the Intergovernmental Oceanographic Commission in 2009 as a new international standard. </p>
<p>“To receive the Prime Minister’s Prize for Science is an incredible honour, and it’s also an honour for the early career researchers that I’ve been working with for the past ten years,” said McDougall.</p>
<p>“They’ve been integral to some of the results that have been recognised in this prize.” </p>
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Read more:
<a href="https://theconversation.com/the-ocean-is-becoming-more-stable-heres-why-that-might-not-be-a-good-thing-157911">The ocean is becoming more stable – here's why that might not be a good thing</a>
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<h2>Predicting sea level rise</h2>
<p>Earth’s oceans and their role in climate change are also the focus of another prize recipient this year – physical oceanographer and ocean modeller Dr Adele Morrison from the Australian National University (ANU). </p>
<p>She won the Malcolm McIntosh Prize for Physical Scientist of the Year for her innovative methods of modelling ocean circulation around Antarctica.</p>
<p>Morrison’s research has greatly reduced uncertainty in predicting future sea level rise from Antarctic ice sheet melt, driven by warm ocean currents in the Southern Ocean.</p>
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<span class="caption">Adele Morrison’s work has revealed the ongoing impact of warm ocean currents on Antarctic ice melt.</span>
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<p>Such work is particularly pertinent to Australia, with 85% of Australians living in places that could soon be affected by rising sea levels.</p>
<p>Morrison hopes to “inspire the next generation of scientists to unravel new discoveries and technologies that limit the impacts of climate change and our transition to a zero-emissions world”.</p>
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Read more:
<a href="https://theconversation.com/satellites-reveal-ocean-currents-are-getting-stronger-with-potentially-significant-implications-for-climate-change-159461">Satellites reveal ocean currents are getting stronger, with potentially significant implications for climate change</a>
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<h2>Molecular diagnostics and solar cell improvements also recognised</h2>
<p>Several other researchers and inventors received accolades at the ceremony held on November 21 at Parliament House in Canberra.</p>
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<li><p>Adjunct Professor Alison Todd and Dr Elisa Mokany, co-founders of the molecular diagnostics company SpeeDx, received the Prize for Innovation. Their highly advanced diagnostic tests have improved diagnosis and treatments for several infectious diseases and cancers.</p></li>
<li><p>The other Prize for Innovation went to Dr Nick Cutmore, Dr James Tickner and Mr Dirk Treasure of the company Chrysos. They have successfully commercialised an X-ray technology that measures the presence of gold and minerals in ore samples.</p></li>
<li><p>Professor Si Ming Man from ANU was awarded the Frank Fenner Prize for Life Scientist of the Year for his work on inflammation and new therapies for inflammatory diseases.</p></li>
<li><p>The Prize for New Innovators went to University of Melbourne’s Dr Pip Karoly, whose unique seizure forecasting technology is improving the lives of millions of people with epilepsy.</p></li>
<li><p>UNSW Associate Professor Brett Hallam was also awarded the Prize for New Innovators, whose discoveries and patented tech have improved solar cell performance by a whopping 10%.</p></li>
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<h2>Inspiring our youngest future scientists</h2>
<p>Each year, the prizes also include recognition for outstanding achievements in science teaching.</p>
<p>Mr George Pantazis from Marble Bar Primary School in Western Australia was awarded the Prize for Excellence in Science Teaching in Primary Schools for his work integrating First Nations cultural knowledge, including the critically endangered Nyamal language, in the school’s science, technology, engineering, and mathematics (STEM) program.</p>
<p>This “wouldn’t be possible without the support of our teachers and the community, in particular the Nyamal people and their Elders”, said Pantazis.</p>
<p>“This prize is the highlight of my career. I owe it all to the students. Without them, I have nothing.”</p>
<p>The Prize for Excellence in Science Teaching in Secondary Schools went to Ms Veena Nair from Viewbank College, Victoria. She has collaborated with countless academics and industry leaders to not only show students the practical application of STEAM (science, technology, engineering, arts and mathematics) subjects, but also find pathways for them in STEAM careers.</p>
<p>“As a first-generation migrant, I’m deeply thankful to my birth country India, where I got my foundation skills – and to my adopted country Australia, where I was given the wings to fly,” said Nair.</p>
<p>For 23 years now, the Prime Minister’s Science Prizes have been awarded for outstanding achievements in scientific research, research-based innovation and excellence in science teaching. The recipients share a prize pool of $750,000.</p>
<p>This is the first year since 2019 the prizes were held at the Parliament House again, with the 2020 and 2021 events having taken place virtually.</p>
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<a href="https://theconversation.com/explainer-whats-the-difference-between-stem-and-steam-95713">Explainer: what's the difference between STEM and STEAM?</a>
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The 2022 Prime Minister’s Science Prizes have been awarded for outstanding achievements in scientific research, innovation and teaching.Signe Dean, Science + Technology Editor, The ConversationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1696332021-10-13T05:58:47Z2021-10-13T05:58:47ZExplainer: why did the High Court rule against Clive Palmer and what does the judgment mean?<p>The High Court has unanimously <a href="https://cdn.hcourt.gov.au/assets/publications/judgment-summaries/2021/hca-30-2021-10-13.pdf">rejected</a> claims by mining magnate Clive Palmer and his company Mineralogy that legislation passed by the Western Australian parliament intended to prevent him from claiming billions in damages was unconstitutional.</p>
<p>The High Court’s decisions are a resounding victory for the Western Australian government. In the short term, the state has been spared a damages claim that may have amounted to nearly $30 billion – almost equivalent to its annual budget. </p>
<p>WA Premier Mark McGowan called the judgment a “monumental victory” for West Australians, saying it confirmed the parliament did “the right thing” by standing up to Palmer.</p>
<p>So, what did the court find and what will it mean for the state moving forward?</p>
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<h2>What the dispute is about</h2>
<p>The dispute between Palmer and the WA government began in 2012 over an iron ore project in the Pilbara. Palmer argued his development proposals for the Balmoral South iron ore project were unlawfully refused by the previous state government. </p>
<p>These claims were pursued through arbitration – a dispute resolution process that happens outside the courts. </p>
<p>In an extraordinary step last year, the WA parliament <a href="https://7news.com.au/news/wa/palmer-v-wa-saga-to-drag-on-as-laws-pass-c-1238792">passed</a> the so-called Mineralogy Act, which sought to protect the state from having to pay any damages to Palmer.</p>
<p>Palmer challenged the Mineralogy Act on a host of grounds, all of which were rejected by the High Court.</p>
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<strong>
Read more:
<a href="https://theconversation.com/how-clive-palmer-could-challenge-the-act-designed-to-stop-him-getting-30-billion-145098">How Clive Palmer could challenge the act designed to stop him getting $30 billion</a>
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<h2>The state can amend agreements with mining companies</h2>
<p>As is common in the mining industry, Mineralogy holds its mining project rights under a “state agreement” with WA. This is an agreement that sets out a framework for mining approvals and payments and is incorporated in an <a href="https://www.legislation.wa.gov.au/legislation/prod/filestore.nsf/FileURL/mrdoc_43096.htm/$FILE/Iron%20Ore%20Processing%20(Mineralogy%20Pty%20Ltd)%20Agreement%20Act%202002%20-%20%5B00-c0-01%5D.html?OpenElement">act of parliament</a>. </p>
<p>Palmer claimed the WA parliament did not follow the proper amendment process outlined in the state agreement when it unilaterally passed the Mineralogy Act. </p>
<p>However, the High Court said the process in the agreement did not apply to parliament. As such, parliament could unilaterally amend the state agreement. </p>
<p>This could have implications for other state agreements with mining companies, as the state could likely change the terms whenever it wants to.</p>
<h2>Denying arbitration awards not unconstitutional</h2>
<p>Palmer and Mineralogy were granted <a href="https://theconversation.com/how-clive-palmer-could-challenge-the-act-designed-to-stop-him-getting-30-billion-145098">two favourable arbitration decisions</a> that were key to their damages claims. He had registered the two awards in the Queensland Supreme Court.</p>
<p>However, the Mineralogy Act deems these arbitration awards to be of no effect. </p>
<p>Palmer argued this meant the Mineralogy Act breached section 118 of the Australian Constitution, which requires full recognition of the laws of other states (in this case, Queensland). </p>
<p>The High Court rejected this argument because all states’ commercial arbitration laws permit a court to refuse to recognise an award if it is invalid in the state where it was made, in this case Western Australia.</p>
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<h2>Not a breach separation of powers</h2>
<p>The separation of powers is a key constitutional principle that says powers should be separated between the three branches of government – the legislature, executive and the judiciary.</p>
<p>Palmer argued the Mineralogy Act interfered with the integrity of the state courts and was an exercise of judicial power by the Western Australian parliament.</p>
<p>The High Court found the effect of the Mineralogy Act might be to change existing legal rights, but this did not amount to a breach of the separation of powers. </p>
<p>The law may have been extreme, but the court ruled it did not interfere with the integrity of the courts, nor was it an exercise of judicial power by the parliament.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/meet-mark-mcgowan-the-wa-leader-with-a-staggering-88-personal-approval-rating-156293">Meet Mark McGowan: the WA leader with a staggering 88% personal approval rating</a>
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<h2>…or a breach of rule of law</h2>
<p>Palmer also argued the Mineralogy Act breached the rule of law by preventing him and his company from pursuing their damages claim.</p>
<p>Although the Australian Constitution does not expressly mention the rule of law, the High Court has said on more than one occasion that it is an “assumption” of the Constitution. </p>
<p>However, the High Court has also said the courts should be wary of giving content to the rule of law that cannot be found in the Constitution itself. In other words, Palmer needed to point to specific provisions of the Constitution that supported his claim the rule of law had been breached. This he was unable to do.</p>
<p>The Mineralogy Act may have changed legal rights, but the court said it did not amount to a breach of the rule of law under the Constitution.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/after-clive-palmers-60-million-campaign-limits-on-political-advertising-are-more-important-than-ever-117099">After Clive Palmer's $60 million campaign, limits on political advertising are more important than ever</a>
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<h2>What are the potential implications of the ruling?</h2>
<p>Mineralogy and Palmer have a number of other related court cases on foot, including a <a href="https://www.comcourts.gov.au/file/Federal/P/QUD257/2020/actions">consumer law claim</a> against Western Australia. </p>
<p>While the High Court did not consider the validity of provisions under the new law directly related to these claims, its ruling may still have an impact. By finding in favour of the state for some of the Mineralogy Act provisions, it may undermine the basis for Palmer’s other claims.</p>
<p>From a political standpoint, the outcome is also likely to bolster the popularity of the McGowan government. </p>
<p>Palmer has also claimed the Mineralogy Act would deter companies from investing in WA, but whether the new law – or the High Court judgement – undermines investor confidence in the state remains to be seen.</p><img src="https://counter.theconversation.com/content/169633/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Murray Wesson has previously received funding from the International Mining for Development Centre (IM4DC).</span></em></p><p class="fine-print"><em><span>Ian Murray has previously received funding from Rio Tinto, BHP Billiton and the Minerals Council of Australia for research relating to Indigenous benefits management structures.</span></em></p>The court said WA’s new law to prevent Palmer from collecting damages against the state was not unconstitutional. Here’s why.Murray Wesson, Senior Lecturer in Law, The University of Western AustraliaIan Murray, Associate Professor, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1676782021-09-20T10:48:34Z2021-09-20T10:48:34ZA giant space rock demolished an ancient Middle Eastern city and everyone in it – possibly inspiring the Biblical story of Sodom<figure><img src="https://images.theconversation.com/files/421903/original/file-20210917-27-aguoxh.jpg?ixlib=rb-1.1.0&rect=6%2C0%2C710%2C608&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artist's evidence-based depiction of the blast, which had the power of 1,000 Hiroshimas.</span> <span class="attribution"><span class="source">Allen West and Jennifer Rice</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>As the inhabitants of an ancient Middle Eastern city now called Tall el-Hammam went about their daily business one day about 3,600 years ago, they had no idea an unseen icy space rock was speeding toward them at about 38,000 mph (61,000 kph).</p>
<p>Flashing through the atmosphere, the rock exploded in a massive fireball about 2.5 miles (4 kilometers) above the ground. The blast was around 1,000 times more powerful than the Hiroshima atomic bomb. The shocked city dwellers who stared at it were blinded instantly. Air temperatures rapidly rose above 3,600 degrees Fahrenheit (2,000 degrees Celsius). Clothing and wood immediately burst into flames. Swords, spears, mudbricks and pottery began to melt. Almost immediately, the entire city was on fire.</p>
<p>Some seconds later, a massive shockwave smashed into the city. Moving at about 740 mph (1,200 kph), it was more powerful than the <a href="https://en.wikipedia.org/wiki/Tornado_records">worst tornado ever recorded</a>. The deadly winds ripped through the city, demolishing every building. They sheared off the top 40 feet (12 m) of the 4-story palace and blew the jumbled debris into the next valley. None of the 8,000 people or any animals within the city survived – their bodies were torn apart and their bones blasted into small fragments. </p>
<p>About a minute later, 14 miles (22 km) to the west of Tall el-Hammam, winds from the blast hit the biblical city of Jericho. Jericho’s walls came tumbling down and the city burned to the ground. </p>
<p>It all sounds like the climax of an edge-of-your-seat Hollywood disaster movie. How do we know that all of this actually happened near the Dead Sea in Jordan millennia ago? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite image showing the area with Tall el-Hammam about 7 miles (12 kilometers) northeast of the Dead Sea" src="https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=384&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=384&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=384&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=483&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=483&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421905/original/file-20210917-31825-1drwpso.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=483&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Now called Tall el-Hammam, the city is located about 7 miles northeast of the Dead Sea in what is now Jordan.</span>
<span class="attribution"><span class="source">NASA</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Getting answers required nearly 15 years of painstaking excavations by hundreds of people. It also involved detailed analyses of excavated material by more than two dozen scientists in 10 states in the U.S., as well as Canada and the Czech Republic. When our group finally <a href="https://doi.org/10.1038/s41598-021-97778-3">published the evidence</a> recently in the journal Scientific Reports, the 21 co-authors included archaeologists, geologists, geochemists, geomorphologists, mineralogists, paleobotanists, sedimentologists, cosmic-impact experts and medical doctors.</p>
<p>Here’s <a href="https://doi.org/10.1038/s41598-021-97778-3">how we built up this picture</a> of devastation in the past.</p>
<h2>Firestorm throughout the city</h2>
<p>Years ago, when archaeologists looked out over excavations of the ruined city, they could see a dark, roughly 5-foot-thick (1.5 m) jumbled layer of charcoal, ash, melted mudbricks and melted pottery. It was obvious that an intense firestorm had destroyed this city long ago. This dark band came to be called the destruction layer.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Excavators stand in a dry landscape with ruins of ancient walls" src="https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421904/original/file-20210917-48847-shp2wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers stand near the ruins of ancient walls, with the destruction layer about midway down each exposed wall.</span>
<span class="attribution"><span class="source">Phil Silvia</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>No one was exactly sure what had happened, but that layer wasn’t caused by a volcano, earthquake or warfare. None of them are capable of melting metal, mudbricks and pottery. </p>
<p>To figure out what could, our group used the <a href="https://impact.ese.ic.ac.uk/ImpactEarth/ImpactEffects/">Online Impact Calculator</a> to model scenarios that fit the evidence. Built by impact experts, this calculator allows researchers to estimate the many details of a cosmic impact event, based on known impact events and nuclear detonations.</p>
<p>It appears that the culprit at Tall el-Hammam was a small asteroid similar to the one that <a href="https://doi.org/10.1117/12.462399">knocked down 80 million trees</a> <a href="https://theconversation.com/mystery-solved-meteorite-caused-tunguska-devastation-15154">in Tunguska, Russia in 1908</a>. It would have been a much smaller version of the <a href="https://theconversation.com/more-bad-news-for-dinosaurs-chicxulub-meteorite-impact-triggered-global-volcanic-eruptions-on-the-ocean-floor-91053">giant miles-wide rock that pushed the dinosaurs into extinction</a> 65 million ago.</p>
<p>We had a likely culprit. Now we needed proof of what happened that day at Tall el-Hammam.</p>
<h2>Finding ‘diamonds’ in the dirt</h2>
<p>Our research revealed a remarkably broad array of evidence.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="magnified images of tiny quartz grains" src="https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=618&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=618&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=618&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=776&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=776&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421943/original/file-20210917-31825-1vbrfje.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=776&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Electron microscope images of numerous small cracks in shocked quartz grains.</span>
<span class="attribution"><span class="source">Allen West</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>At the site, there are finely fractured sand grains called shocked quartz that only form at 725,000 pounds per square inch of pressure (5 gigapascals) – imagine six <a href="https://man.fas.org/dod-101/sys/land/m1.htm">68-ton Abrams military tanks</a> stacked on your thumb.</p>
<p>The destruction layer also contains tiny <a href="https://doi.org/10.1086/677046">diamonoids</a> that, as the name indicates, are as hard as diamonds. <a href="https://doi.org/10.1086/677046">Each one is smaller</a> <a href="https://doi.org/10.1016/j.chroma.2016.08.056">than a flu virus</a>. It appears that wood and plants in the area were instantly turned into this diamond-like material by the fireball’s high pressures and temperatures.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=561&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=561&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421909/original/file-20210917-27-7y1o9c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=561&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Diamonoids (center) inside a crater were formed by the fireball’s high temperatures and pressures on wood and plants.</span>
<span class="attribution"><span class="source">Malcolm LeCompte</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Experiments with laboratory furnaces showed that the bubbled pottery and mudbricks at Tall el-Hammam liquefied at temperatures above 2,700 F (1,500 C). That’s hot enough to <a href="https://www.onlinemetals.com/en/melting-points">melt an automobile</a> within minutes.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="magnified view of spherical shapes" src="https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=594&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=594&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=594&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=746&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=746&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421942/original/file-20210917-27-5s3b15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=746&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Spherules made of melted sand (upper left), palace plaster (upper right) and melted metal (bottom two).</span>
<span class="attribution"><span class="source">Malcolm LeCompte</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>The destruction layer also contains tiny balls of melted material smaller than airborne dust particles. <a href="https://doi.org/10.1073/pnas.1301760110">Called spherules</a>, they are made of vaporized iron and sand that melted at about 2,900 F (1,590 C).</p>
<p>In addition, the surfaces of the pottery and meltglass are speckled with tiny melted metallic grains, including iridium with a <a href="https://www.rsc.org/periodic-table/element/77/iridium">melting point of 4,435 F</a> (2,466 C), platinum that <a href="https://www.rsc.org/periodic-table/element/78/platinum">melts at 3,215 F</a> (1,768 C) and <a href="https://en.wikipedia.org/wiki/Zirconium(IV)_silicate">zirconium silicate at 2,800 F</a> (1,540 C).</p>
<p>Together, all this evidence shows that temperatures in the city rose higher than those of volcanoes, warfare and normal city fires. The only natural process left is a cosmic impact.</p>
<p>The same evidence is found at known impact sites, such as <a href="https://theconversation.com/mystery-solved-meteorite-caused-tunguska-devastation-15154">Tunguska</a> and the <a href="https://theconversation.com/more-bad-news-for-dinosaurs-chicxulub-meteorite-impact-triggered-global-volcanic-eruptions-on-the-ocean-floor-91053">Chicxulub crater</a>, created by the asteroid that triggered the dinosaur extinction.</p>
<p>One remaining puzzle is why the city and over 100 other area settlements were abandoned for several centuries after this devastation. It may be that high levels of salt deposited during the impact event made it impossible to grow crops. We’re not certain yet, but we think the explosion may have vaporized or splashed toxic levels of Dead Sea salt water across the valley. Without crops, no one could live in the valley for up to 600 years, until the minimal rainfall in this desert-like climate washed the salt out of the fields. </p>
<h2>Was there a surviving eyewitness to the blast?</h2>
<p>It’s possible that an oral description of the city’s destruction may have been handed down for generations until it was recorded as the story of Biblical Sodom. The Bible <a href="https://sarata.com/bible/chapter/Genesis.19.html#19:24">describes the devastation of an urban center</a> near the Dead Sea – <a href="https://www.biblegateway.com/passage/?search=Luke+17%3A28%E2%80%9330&version=NRSV">stones and fire fell from the sky</a>, more than one city was destroyed, thick smoke rose from the fires and city inhabitants were killed.</p>
<p>Could this be an ancient eyewitness account? If so, the destruction of Tall el-Hammam may be the second-oldest destruction of a human settlement by a cosmic impact event, after the village of <a href="https://doi.org/10.1038/s41598-020-60867-w">Abu Hureyra in Syria about 12,800 years ago</a>. Importantly, it may the first written record of such a catastrophic event.</p>
<p>[<em>Over 110,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p>The scary thing is, it almost certainly won’t be the last time a human city meets this fate.</p>
<figure>
<img src="https://d2pn8kiwq2w21t.cloudfront.net/images/imagesasteroid20180723main-animation-16.width-1320.gif">
<figcaption><span class="caption">Animation depicting the positions of known near-Earth objects at points in time for the 20 years ending in January 2018. <i>Credit: NASA/JPL-Caltech</i></span></figcaption>
</figure>
<p>Tunguska-sized airbursts, such as the one that occurred at Tall el-Hammam, can devastate entire cities and regions, and they pose a severe modern-day hazard. As of September 2021, there are <a href="https://cneos.jpl.nasa.gov/stats/totals.html">more than 26,000 known near-Earth asteroids</a> and a hundred short-period near-Earth comets. One will inevitably crash into the Earth. Millions more remain undetected, and some may be headed toward the Earth now.</p>
<p>Unless orbiting or ground-based telescopes detect these rogue objects, the world may have no warning, just like the people of Tall el-Hammam.</p>
<p><em>This article was co-authored by research collaborators archaeologist <a href="https://www.researchgate.net/profile/Phillip-Silvia">Phil Silvia</a>, geophysicist <a href="https://www.researchgate.net/profile/Allen-West">Allen West</a>, geologist <a href="https://www.researchgate.net/profile/Ted-Bunch-2">Ted Bunch</a> and space physicist <a href="https://www.researchgate.net/profile/Malcolm-Lecompte">Malcolm LeCompte</a>.</em></p><img src="https://counter.theconversation.com/content/167678/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher R. Moore does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>New research suggests that fire from the sky in the form of a small asteroid annihilated a city near the Dead Sea 3,600 years ago.Christopher R. Moore, Archaeologist and Special Projects Director at the Savannah River Archaeological Research Program and South Carolina Institute for Archaeology and Anthropology, University of South CarolinaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/641522016-12-09T02:07:57Z2016-12-09T02:07:57ZCatching lightning in a fossil – and calculating how much energy a strike contains<figure><img src="https://images.theconversation.com/files/149316/original/image-20161208-31402-vgl94l.jpg?ixlib=rb-1.1.0&rect=229%2C9%2C1634%2C1299&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Very powerful, try to avoid.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/rickywilson/2569675373">Rick Wilson</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>For most of human history, people have been terrified by lightning. <a href="http://www.sacred-texts.com/afr/fssn/fsn21.htm">Frightening bolts from above</a>, lightning was a <a href="http://lightningsafety.com/nlsi_info/myths.html">tool of the gods</a> to smite mortals for their hubris (or their unfortunate penchant for seeking shelter from storms under trees). The discovery and implementation of <a href="https://www.fi.edu/history-resources/franklins-lightning-rod">Benjamin Franklin’s lightning rod</a> tamed this once formidable, divine weapon.</p>
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<a href="https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=897&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=897&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=897&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1127&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1127&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149318/original/image-20161208-31352-1m75vph.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1127&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Will a lightning bolt contain enough energy to blast Marty McFly through time?</span>
</figcaption>
</figure>
<p>Nonetheless, lightning’s strength still lingers in our imagination. Hollywood considers it powerful enough to allow strangely designed cars from the early 1980s to <a href="http://www.imdb.com/title/tt0088763/">break the space-time continuum</a>. In the comic book world, it’s an ingredient in the <a href="https://en.wikipedia.org/wiki/Flash_(Barry_Allen)">formula for developing superpowers</a>. It has also been given the power to <a href="https://en.wikipedia.org/wiki/Frankenstein%27s_monster">return life to the dead</a>, though not always with the intended effect.</p>
<p>Just how much energy actually is in a lightning bolt? It may seem like this question should have been definitively answered before, but it turns out it’s difficult to answer quantitatively. In my research, we <a href="http://doi.org/10.1038/srep30586">tackled this issue in a new way</a>: We deduced how big a bolt of lightning was based on the size of rocks formed by lightning.</p>
<h2>Rough estimates</h2>
<p>Lightning is obviously powerful: One need only look at a tree that it’s splintered down the center for proof. Lightning generates temperatures hotter than the surface of the sun, <a href="http://doi.org/10.1016/0021-9169(64)90113-8">in excess of 20,000 degrees Celsius</a>, a temperature that is otherwise unrelateable to the human experience.</p>
<p>This temperature measurement provides <a href="http://doi.org/10.1029/RG022i004p00363">one way to estimate the energy of lightning</a>. It takes a certain amount of energy to heat air to a high temperature. By measuring the length of a lightning strike, multiplying it by the energy per length required to heat up the air to tens of thousands of degrees, we can calculate lightning’s energy.</p>
<p>Alternatively, we can approach the measurement of lightning energy by considering the voltage of a strike. A volt is a measurement of the amount of energy released as each pack of electrons flows from one side of an object to another – for instance, a battery. When lightning strikes, we can determine the <a href="http://doi.org/10.1109/15.249398">voltage it induces on nearby powerlines</a>; measurements range from hundreds of thousands to millions of volts. From <a href="https://en.wikipedia.org/wiki/Ohm%27s_law">Ohm’s law</a>, we can calculate the power of lightning by multiplying this by the number of electrons that move during the strike, a value known as the current. If we know the duration of this strike, we can then calculate the energy.</p>
<p>These methods have a large range of errors: not calculating the length of the lightning strike correctly, or getting the amount of gas heated per length wrong, or the temperature, or voltage, or number of electrons – all give pretty large errors for these calculations. </p>
<p>Could there be another route to calculating lightning energy that might pare down some of these errors? Florida’s unique geology provided an interesting route to answering this question.</p>
<h2>Fossilized lightning</h2>
<p>Florida tends to be a fairly boring state for a rock enthusiast. There’s sand, and there’s limestone. Not much else, and all of it is young, geologically speaking. Sometimes the sand is on top of the limestone, and sometimes it’s on the side. Sometimes the sand was deposited 15 million years ago, sometimes 5 million years ago. There’s a lot of sand. </p>
<p>Florida’s weather is a bit more interesting; it’s actually the U.S. state <a href="http://www.vaisala.com/VaisalaImages/Lightning/avg_sd_2005-2014_CONUS_2km_grid.png">most often struck by lightning</a>. A lot of times this lightning strikes the sand that covers the state. When it does so, it creates a new type of rock, called a fulgurite – a hollow tube formed as the lightning travels through the sand, vaporizing it and melting its outer edges. When the sand cools down, which happens quickly, the hollow tube is frozen in glass, recording the path the lightning traveled. By definition, a fulgurite is a metamorphic rock, changed by heat and pressure, from sand to something new.</p>
<p>Fulgurites are generally rare, unless you know where to look. Central peninsular Florida hosts several sand mines that supply the raw material for roads and cement, golf courses and playgrounds. At one site, we collected several hundred fulgurites; more than 250 lay in the field, with many more found in spoil piles, filtered out of the sand prior to its being loaded onto trucks.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149290/original/image-20161208-31383-kx7vxr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The sand mine in Polk County, Florida, from which the fulgurites were collected.</span>
<span class="attribution"><span class="source">Matthew Pasek</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>These sites are not really any different than any place else in Florida – they aren’t some sort of lightning magnet – but the geologic setting was just right for keeping them around for a long time. These sand mines probably have about one million year’s worth of fulgurites buried inside of them. They’re easy to find – since glass isn’t something you want in commercial sand, the mine filters them out.</p>
<p>The fulgurites range in thickness from about the size of a baby’s little finger to about the size of man’s arm in thickness. The thicker ones had to be formed by much more energetic lightning bolts: a thicker fulgurite means more sand had to be vaporized. Most fulgurites we recovered were short fragments, though the longest ones found were a yard or two long.</p>
<h2>Calculating from the fulgurites</h2>
<p>It takes a specific amount of energy to vaporize sand into gas. First the sand has to be heated to around 1700°C, about the temperature of molten lava. At this temperature, the sand melts. The molten sand then has to heat to just shy of 3000°C, when it vaporizes. It takes about 15 megajoules of energy to heat and vaporize a kilogram of sand. That’s about the amount of energy the average U.S. household consumes in six hours, or the kinetic energy an average car would have if it were going 300 miles per hour.</p>
<figure class="align-center zoomable">
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<figcaption>
<span class="caption">The largest fulgurite found during recovery at the sand mine.</span>
<span class="attribution"><span class="source">Matt Pasek</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>After measuring our fulgurites, we determined that on average, the energy required to form these rocks was at least about one megajoule per meter of fulgurite formed. We calculated the energy per meter since, again in most cases, the fulgurites we had collected were broken. </p>
<p>So based on our calculations, how close does Hollywood come, with estimates like in “Back to the Future” of 1.21 gigawatts of power in lightning? Power is energy per time, and our measurements of fulgurites suggest that megajoules of energy make rock in thousandths to millionths of seconds. So a gigawatt is actually on the low side – lightning power may be a thousand times that, reaching into the terawatts, though the average is probably tens of gigawatts.</p>
<p>That’s enough energy to power about a billion houses, albeit only for a few millionths of a second. Unfortunately, given its sporadic and unpredictable nature, no power grid will ever be able to harness lightning effectively. But with that much power, perhaps breaking the space-time continuum in a souped-up Delorean is not so unfeasible after all….</p>
<h2>An oddity in the pattern</h2>
<p>When we looked at these fulgurites in depth, something odd came out of the data. Our energy measurements followed something called a “lognormal” trend.</p>
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<p>Rather than following the bell curve we often see in the distribution of natural phenomena – like, for instance, the heights of American men – the energy curve was less equally balanced. For heights, the same number of men are two inches above average as are two inches below. But for lightning, the large lightning strikes were much larger than the average, while the smaller strikes were not so much smaller than the average. Strikes that were twice the average were as frequent as those that were half the average.</p>
<p>Now why might this be at all interesting or useful? Measuring the energy in lightning is a way of measuring potential damage: A lightning strike can vaporize rock, so what might it do to wood or electronics? Our measurements show that the biggest lightning strikes are multiples of the average lightning strikes: A big one might be 20 times as large as the average. That’s a lot for a <a href="https://en.wikipedia.org/wiki/Lightning_rod#Lightning_protection_system">lightning protection system</a> to handle. The peak energy calculated from our rock-based method may give an idea as to the maximum damage we may expect, and may eventually allow for better preparation against the worst-case scenario.</p><img src="https://counter.theconversation.com/content/64152/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Pasek receives funding from NASA Exobiology and Evolutionary Biology (Grant NNX14AN96G)</span></em></p>Lightning strikes are powerful – but we haven’t had solid estimates of their energy until now. Researchers turned to the hollow stone tubes they create by vaporizing sand for more precise calculations.Matthew Pasek, Associate Professor of Geosciences, University of South FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/469912015-09-28T03:30:42Z2015-09-28T03:30:42ZAncient minerals on Earth can help explain the early solar system<figure><img src="https://images.theconversation.com/files/96173/original/image-20150925-16033-qplrah.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The early solar system was once a turbulent place.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/34547181@N00/15763988775">Flickr/Philippe Put</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>A new discovery of an extremely rare mineral, called <a href="http://www.mindat.org/min-11467.html">reidite</a>, from a layer of rock in the North West Highlands of Scotland may seem utterly insignificant on first glance. But this occurrence of reidite has major implications for understanding the early evolution of our solar system.</p>
<p>To comprehend the significance of these small specs of reidite, we must first consider the moon.</p>
<p>The most obvious features on the moon’s surface are the circular craters formed by countless meteorite impacts. The dating of <a href="http://www.lpi.usra.edu/lunar/missions/apollo/apollo_11/samples/">lunar samples</a> collected during the Apollo missions tells us that many of these impacts formed around 3.9 billion years ago, which was relatively early in the evolution of our 4.6 billion year old solar system.</p>
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<figcaption>
<span class="caption">Impact craters on the moon date back many billions of years.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasacommons/9457381915/">Flickr/NASA on The Commons</a></span>
</figcaption>
</figure>
<p>This intense period of meteorite impact events, often referred to as the <a href="http://www.bbc.co.uk/science/earth/earth_timeline/late_heavy_bombardment">Late Heavy Bombardment</a> hypothesis, has attracted much interest over the past 40 years. But there is a growing body of alternative models that could account for the many impact craters on the moon and hence Earth, and these require a different evolutionary hypothesis for the early solar system.</p>
<h2>Crater impressions on Earth</h2>
<p>Compared to the moon, the Earth appears to record relatively few impact events. Yet because of its size, Earth should have experienced about 20 times more impacts than the moon. </p>
<p>This apparent discrepancy can be explained by the dynamic nature of the Earth’s crust. Tectonic plates on Earth are in continuous motion and over time, which leads to the destruction, erosion and/or burial of impact craters. There are almost no intact rocks remaining that would have been around to witness the Late Heavy Bombardment. </p>
<p>Fortunately, zircon – a mineral that is found in small amounts in many of Earth’s rocks – gives us the chance to interrogate the early impact history. Zircon contains trace amounts of <a href="http://www.rsc.org/periodic-table/element/92/uranium">uranium</a>, whose radioactive decay to <a href="http://www.rsc.org/periodic-table/element/82/lead">lead</a> can be used for precise dating of geological events. </p>
<p>Zircon is very resilient to almost all physical and chemical processes. Incredibly old grains, up to 4.4 billion years old, have been found as eroded detritus now preserved in younger sedimentary rocks. These ancient zircons have proven to be an invaluable repository of the geological conditions and processes that operated on Earth shortly after its formation, and may potentially preserve the ancient impact history of the Late Heavy Bombardment.</p>
<p>The question is, how do we recognise zircon grains that have been impacted by a meteorite? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=479&fit=crop&dpr=1 600w, https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=479&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=479&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=602&fit=crop&dpr=1 754w, https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=602&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/94090/original/image-20150908-2016-14o6voa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=602&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Reidite layers (yellow) within a host zircon grain (red)</span>
<span class="attribution"><span class="source">Steven Reddy/Curtin University</span></span>
</figcaption>
</figure>
<p>In the past decade a number of <a href="http://link.springer.com/article/10.1007%2Fs00410-006-0174-4">studies</a> have shown that zircon can contain microscopic features, called microstructures, that indicate that the grain has been stressed and deformed as a result. Unfortunately, these microstructures are not diagnostic of impacts in many cases, and may have formed by plate tectonic processes.</p>
<p>But reidite, which has the same chemical composition as zircon, only forms from zircon at the extremely high-pressure shock conditions imposed by an impacting meteorite; pressures equal to those found around 900km below Earth’s surface.</p>
<p>The reidite discovered in Scotland was found as microscopic layers only 2μm wide (about 1/40th the thickness of the average human hair) within grains of zircon. Yet even at these microscopic levels its presence represents the smoking gun of a meteorite impact. </p>
<p>Until a year ago, the three known occurrences of reidite were all associated with impacts that were less than 35 million years ago, which is very young, geologically speaking. It seemed likely that ancient reidite reverted back to zircon. </p>
<h2>New finds of ancient times</h2>
<p>In 2015 two new discoveries have extended the known occurrence of reidite. The <a href="http://geology.gsapubs.org/content/43/4/315">first</a> was dated to around 450 million years ago and the second, the <a href="http://geology.gsapubs.org/content/43/10/899">Scottish example</a>, at around 1.2 billion years. These discoveries were made at Curtin University in Perth, and identified the reidite using electron backscatter diffraction, a high resolution scanning electron microscopy technique.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=327&fit=crop&dpr=1 600w, https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=327&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=327&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=411&fit=crop&dpr=1 754w, https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=411&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/94085/original/image-20150908-1996-skeqep.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=411&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The outcrops around Stac Fada in Scotland where the new reidite was discovered.</span>
<span class="attribution"><span class="source">Tim Johnson / Curtin University</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Despite the minute size of the Scottish reidite, the discovery is extremely important. It shows that reidite is stable over long periods of geological time and does not necessarily revert back to zircon. This opens up the potential of using reidite to clearly identify ancient impact events recorded in shocked zircon grains that may be preserved in the detritus of sedimentary rocks formed long after the time of impact. </p>
<p>Establishing the early Earth impact record is challenging. Four billion year old reidite remains elusive, and the ability to constrain the absolute timing of impact events in reidite-bearing zircon grains has yet to be proven.</p>
<p>We are currently looking for evidence of older reidite and are exploring how deformation associated with reidite formation may modify the distribution of elements over incredibly small distances within host zircon. </p>
<p>These micro- and nanoscale observations on Earth’s ancient zircon grains may yield the information that will allow us to test the competing models of the early Earth’s impact record and say something useful about the early evolution of the solar system.</p><img src="https://counter.theconversation.com/content/46991/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steven Reddy receives funding from the Australian Research Council and the Science and Industry Endowment Fund. </span></em></p>The early solar system was a busy place with plenty of meteorite impacts on the new planets and moons. But finding evidence of such impacts on Earth can be tricky.Steven Reddy, Professor of Geology and Geoscience Atom Probe Science Leader, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.