Balanced rocks set design ground motion values for New Zealand dam

SEISMOLOGICAL SOCIETY OF AMERICA

Research News

 

IMAGE: FRAGILE GEOLOGIC FEATURE, CLYDE DAM AREA, NEW ZEALAND. view more 

CREDIT: MARK STIRLING

For the first time, researchers have used precariously-balanced rocks to set the formal design earthquake motions for a major existing engineered structure--the Clyde Dam, the largest concrete dam in New Zealand.

Mark Stirling of the University of Otago and colleagues identified and assessed the ages of these gravity-defying rock formations located about 2 kilometers from the dam site, using these data to determine the peak ground accelerations that the rocks could withstand before toppling.

This in turn was used to set the Safety Evaluation Earthquake (SEE) spectrum for the dam, or the expected peak earthquake ground motions occurring with a return period of 10,000 years that governs the safety assessment and seismic design of the structure.

As the researchers report in the Bulletin of the Seismological Society of America, the peak ground acceleration for the new SEE spectrum, developed from the rock data as well as an updated seismic hazard model for the region, is significantly reduced compared to their preliminary estimates developed in 2012.

However, the new design ground motion values are similar to those used--by chance--when the dam was built in the 1980s. "There is nothing that needs to be done in the way of dam strengthening," said Stirling. "However, the study shows all the relevant authorities that the dam is compliant given the modern regulations."

The study also "serves as an important proof-of-concept for future applications of fragile geologic features (FGFs) in engineering design," Stirling and his colleagues write.

FGFs are especially useful in setting engineering design parameters in places where the period between relevant earthquakes is very long--10,000 years or more. In these cases, the geologic features can help test probabilistic seismic hazard estimates. While seismologists have explored the usefulness of these features for other engineering design projects, such as the canceled Yucca Mountain nuclear waste repository in Nevada and the Diablo Canyon power plant in California, the Clyde Dam is the first to use fragile features to set design ground motion.

The Clyde Dam is located in the Central Otago "Range and Basin" region of the southern part of New Zealand's South Island. On a broad plateau located southwest of the dam called Cairnmuir flat, outcrops of schist rock that stick up above the landscape are carved by erosion into potentially unstable configurations.

In a painstaking effort, Stirling and colleagues identified these precariously-balanced rocks and took field measurements of their geometries to estimate their fragility. Then the researchers analyzed the formations using radionuclide data that estimate how long a rock surface has been exposed to the atmosphere. These data can show how long a rock has been balanced in a specific position.

"In terms of data collection, it was the FGF age estimation that was most challenging," said Stirling. "It required specialist input, hard physical work, and there were usually large uncertainties in interpreting the dates to say how long the FGFs had been fragile."

By combining these data with information on past earthquakes along the nearby Dunstan fault, Stirling and colleagues concluded that the rocks at Cairnmuir flat had been poised in their unstable positions since at least 24,000 years ago. This suggests that all of them have survived at least two Dunstan fault earthquakes.

The researchers then developed a fragility distribution of all precariously-balanced rocks in their study, based on peak ground acceleration, to determine the peak ground accelerations most likely to topple any random fragile rock structure with greater than 95% probability. This information was used to recommend a new SEE spectrum for the dam site.

Preliminary probabilistic seismic hazard calculations for the site suggested that "the FGFs in the area would be knocked down by these strong ground motions if they occurred--it's easy to roughly estimate the fragility of the features by eye in the field," Stirling explained. But since the features are still standing tall, it was then only a matter of time and research, he added, before the new Clyde Dam hazard estimates were revised.

CAPTION

Fragile geologic feature, Clyde Dam area, New Zealand.

CREDIT

David Barrell

CAPTION

Fragile geologic feature, Clyde Dam area, New Zealand.

CREDIT

David Barrell

 

Research suggests ways to tackle water security challenges in world's drylands

UNIVERSITY OF YORK

Research News

 

IMAGE: DRYLANDS view more 

CREDIT: LINDSAY STRINGER

The research - published ahead of World Day to Combat Desertification and Drought on 17 June 2021 - examines recent and projected climate change impacts on water security across the world's drylands up to the year 2100.

It concludes that more efficient water management, technology and infrastructure, and better demand and supply management can offer more equitable access to water resources and help to achieve development goals.

Lead author, Professor Lindsay Stringer from the Department of Environment and Geography at the University of York said "People in dryland areas are already adapting to climate changes, but they need to be supported with coherent system-oriented policies and institutions that put water security at their core."

Globally, water scarcity already affects between one and two billion people. Drylands in hot, tropical areas have already experienced temperature rises under climate change that is higher than the global average.

Projected climate changes indicate that in a few decades, millions more people (approximately half the world's population) will be living under conditions of high water stress.

The drylands' human and environmental systems could be hampered in their ability to adapt to water dynamics under climate change, with knock-on effects for other places beyond the drylands as well.

The paper's authors strongly support the integration of water concerns across borders and sectors, through approaches such as Integrated Water Resources Management (IWRM).

Professor Stringer said "To make sure no one gets left behind, more attention needs to be paid to how decisions about water management link to other things, like food, energy, livelihoods, migration and human health."

Professor Stringer also argues that achieving water security is not just an environmental challenge, but also a governance issue "We need to ensure access to water and its quality is properly managed. That requires political will, capacity, resourcing and leadership to develop a truly integrated approach to delivering water-related decisions."

"Stakeholder engagement is increasingly important, particularly in complex contexts where dryland rivers flow across multiple national borders, and approaches like IWRM are really vital in shaping more equitable water resource allocation."

The research is published in One Earth.

CAPTION

Wetlands in Drylands

CREDIT

Lindsay Stringer

Notes to editors

Professor Lindsay Stringer is currently a coordinating lead author for the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report.

DOI: https://doi.org/10.1016/j.oneear.2021.05.010

Bed sharing does not lead to stronger infant-mother attachment or maternal bonding

New research led by the University of Kent has found that there is no link between bed sharing, infant-mother attachment, and infant behavioral outcomes

UNIVERSITY OF KENT

Research News

 

New research led by the University of Kent has found that there is no link between bed sharing, infant-mother attachment, and infant behavioural outcomes.

Contrary to previous beliefs that bed sharing is beneficial (or even required) for babies to develop a secure attachment style and for mothers to develop a strong bond to their baby, researchers have found that it is neither associated with positive or negative outcomes related to infant attachment and maternal bonding.

There is a lot of controversial debate about bed sharing by parents and the infant sleep literature, in particular. Notably, researchers and practitioners recommend against bed sharing, particularly before four months of age due to the increased risk of Sudden Infant Death Syndrome (SIDS).

In reality, parents quite often share their bed with their baby due to several reasons such as practicality and breastfeeding, or because they follow the idea of 'attachment parenting'.

The research paper, published by the Journal of Developmental & Behavioral Pediatrics, analyses data from 178 infants and their parents, at term, three, six and eighteen months. No associations between bed sharing during the first six months and infant-mother attachment and infant behavioural outcomes (attention levels/hyperactivity and task persistence) at eighteen months were found. Similarly, there were no associations between bed sharing during the first six months and maternal bonding and sensitivity in interacting with the infant at consequent assessment points.

This new study, led by Dr Ayten Bilgin (Kent's School of Psychology) alongside Professor Dieter Wolke, Professor of Developmental Psychology and Individual Differences at the University of Warwick concludes that longer follow-up studies on effects on child development may be required.

Dr Bilgin said: 'A lot of people think that bed sharing is necessary to promote secure attachment with infants. However, there is little research in this area and quite mixed evidence. More insight into the outcomes of bed sharing is required to better inform parents, guardians and practitioners.'

Professor Wolke said: 'Around a third of all parents share their bed with their infant during the first 18 months of life occasionally to most nights in this UK study. We found the practice was associated with ease of breastfeeding and dealing with night waking of the baby.'

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The research paper 'Bed-Sharing in the First 6 Months: Associations with Infant-Mother Attachment, Infant Attention, Maternal Bonding and Sensitivity at 18 Months' is published by the Journal of Developmental & Behavioral Pediatrics. doi: 10.1097/DBP.0000000000000966

At underwater site, research team finds 9,000-year-old stone artifacts

Underwater archaeology team finds ancient obsidian flakes 2,000 miles from quarry

UNIVERSITY OF TEXAS AT ARLINGTON

Research News

 

IMAGE: ASHLEY LEMKE, UT ARLINGTON view more 

CREDIT: UT ARLINGTON

An underwater archaeologist from The University of Texas at Arlington is part of a research team studying 9,000-year-old stone tool artifacts discovered in Lake Huron that originated from an ocentral Oregon.

The obsidian flakes from the underwater archaeological site represent the oldest and farthest east confirmed specimens of western obsidian ever found in the continental United States.

obsidian quarry more than 2,000 miles away in "In this case, these tiny obsidian artifacts reveal social connections across North America 9,000 years ago," said Ashley Lemke, assistant professor of sociology and anthropology at UT Arlington. "The artifacts found below the Great Lakes come from a geological source in Oregon, 4,000 kilometers away---making it one of the longest distances recorded for obsidian artifacts anywhere in the world."

The unique study was a multi-faceted pursuit with divers in the water and researchers in the laboratory from UTA, the University of Michigan, Lake Superior National Marine Conservation Area, the University of Missouri Research Reactor Center, the Northwest Research Obsidian Studies Laboratory and the University of Georgia. Their combined work, "Central Oregon obsidian from a submerged early Holocene archaeological site beneath Lake Huron," was published last month in the journal PLOS One.

Because the site was underwater and undisturbed, researchers systematically and scientifically recovered the obsidian, a form of volcanic glass that was used and traded widely throughout much of human history as a prized material for making sharp tools.

"These are very small pieces that have very large stories to tell," Lemke said. "Obsidian from the far western United States is rarely found in the east."

Lemke is a leader and innovator in the field, serving as the chair of the Advisory Council on Underwater Archaeology, an international group dedicated to underwater archaeology and the preservation of underwater cultural resources. She is an expert on submerged ancient sites in the Americas and has researched other areas such as the Gulf of Mexico and Atlantic Ocean.

The find in Lake Huron is part of a broader study to understand the social and economic organization of caribou hunters at the end of the last ice age. Water levels were much lower then; scientists have found, for example, ancient sites like stone walls and hunting blinds that are now 100 feet underwater.

"This particular find is really exciting because it shows how important underwater archaeology is," Lemke said. "The preservation of ancient underwater sites is unparalleled on land, and these places have given us a great opportunity to learn more about past peoples."

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Study reveals bycatch risk for dolphins and porpoises in global small-scale fishe

A new study by Newcastle University shows that the risk of dolphins and porpoises being caught in small-scale (artisanal) fisheries is highest in low- and middle-income regions around the tropics and sub-tropics

NEWCASTLE UNIVERSITY

Research News

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IMAGE: THE BYCATCH THREAT OF GLOBAL SMALL-SCALE FISHERIES. view more 

CREDIT: PRODELPHIUS, PERU

A new study by Newcastle University shows that the risk of dolphins and porpoises being caught in small-scale (artisanal) fisheries is highest in low- and middle-income regions around the tropics and sub-tropics.

Marine scientists assessed the risk posed by small-scale fisheries to all 72 species of toothed whales found throughout the world's oceans. They found that this risk was highest in the Central Indo-Pacific, Temperate Northern Pacific, Temperate South America and the Western Indo-Pacific.

Publishing their findings in the journal Fish and Fisheries, the authors argue that addressing the bycatch risks posed by small-scale fisheries in the high-risk regions is especially challenging and must be considered a global priority for toothed whale conservation.

They warn that immediate management and conservation actions are required to reduce and ideally eliminate small-scale fisheries bycatch to prevent species extinctions.

Dr Andrew Temple, Research Associate at the School of Natural and Environmental Sciences and Senior Consultant at MRAG Ltd said: "Fisheries are the greatest threat to the survival of dolphins, porpoises and other toothed whales worldwide. This is the first study to take a global perspective on the threat to these species from small-scale fisheries."

Professor Per Berggren, of Newcastle University's School of Natural and Environmental Sciences, continued: "Small-scale fisheries are a particular threat to species found in coastal shallow waters where dolphin and porpoise distribution overlaps with gillnets use. Our results suggest that some of the most at-risk species are the four species of humpback dolphins, Irrawaddy dolphin, Australian snubfin dolphin, Franciscana dolphin, Guiana dolphin, Indo-Pacific finless porpoise, and the likely soon to be extinct vaquita."

Dr Andrew Temple added: "Our results highlight a "wicked problem" for toothed whale bycatch in small-scale fisheries. Small-scale fisheries are vital to the food, nutritional, and economic security of many communities in low- and middle-income nations. Managers of these fisheries therefore have to carefully balance the actions required to save these species against the risks that these actions might result in unintentional harm to fishing communities that rely on the oceans for their livelihoods. Solving this "wicked problem" is made even more challenging because funds available to fisheries managers are generally more limited in these high-risk regions, making effective fisheries management extremely difficult."

The study authors recognise that conservation actions need to be realistic and will certainly require international collaboration and cooperation. They call for mitigation actions that are tailored to the specific local economic and social contexts, and balance species and human needs.

CAPTION

Global risk assessment of toothed whale by-catch in small-scale fisheries by Large Marine Ecoregion (LME) Realms. (a) Relative risk scores by LME Realm, calculated as the Euclidean distance with fisheries pressure risk and species susceptibility risk as axes. (b) Fisheries pressure relative risk score by LME Realm. (c) Species susceptibility relative risk score by LME Realm. (d) Relative risk scores by LME Realm with associated weighted mean standard errors displayed. LME Realms = Arctic, Central Indo-Pacific (CIP), Eastern Indo-Pacific (EIP), Temperate Australasia (TA), Temperate Northern Atlantic (TNA), Temperate Northern Pacific (TNP), Temperate South America (TSA), Temperate Southern Africa (TSAf), Tropical Atlantic (TAt), Tropical Eastern Pacific (TEP) and Western Indo-Pacific (WIP).

Drone cameras record social lives of killer whales

A new study led by the University of Exeter and the Center for Whale Research suggests killer whales may socialise with each other based on age and gender, with younger whales and females more sociable than other groups.

The research used drone cameras to study one pod of southern resident killer whales off the US coast of Washington State, in the Pacific Ocean.

Around 10 hours of footage was captured over 10 days.

Australia whales: ‘Unbelievable’ super-group caught on film

When a drone pilot captured footage of an enormous group of whales off the New South Wales coast last year, it sent scientists into a frenzy.

A pod of that size - known as a super-group - and the "bubble-net" feeding behaviour they were displaying had never been documented off Australia before.

A research paper has now confirmed both extraordinary events.

Video by Isabelle Rodd.

#FREERAIF
Mustafa al-Darwish: Saudi man executed for crimes committed as a minor

Mustafa al-Darwish was arrested in 2015 and charged with trying to carry out an armed revolt

Saudi Arabia has executed a man for offences that rights groups say he committed while aged 17, despite the kingdom's assurance that it had abolished the death penalty for minors.

Mustafa Hashem al-Darwish was arrested in 2015 for protest-related offences.

Saudi authorities say he was charged with forming a terror cell and trying to carry out an armed revolt.

But rights groups had called for a stop to his execution, saying their trial had been unfair.

Amnesty International and Reprieve, an anti-death penalty charity, say 26-year-old al-Darwish had already recanted his confession, which was allegedly made after he was tortured. Saudi authorities have not publicly commented on the accusation.

According to Reuters news agency, al-Darwish's charges included "seeking to disturb security by rioting" and "sowing discord".

Evidence against him included a picture "offensive to the security forces", and his participation in over 10 "riot" gatherings in 2011 and 2012.

Reform and repression go hand in hand in Saudi Arabia

The Saudi interior ministry said al-Darwish had also attempted to kill local security forces, state media reports. However court documents did not specify the dates of any of his offences, according to Reuters.

Reprieve said al-Darwish's family received no warning about the execution in advance, and only learned about it online.

"How can they execute a boy because of a photograph on his phone?," his family said in a statement, published by Reprieve. "Since his arrest, we have known nothing but pain. It is a living death for the whole family."

The Saudi interior ministry, cited by state news agency SPA, said al-Darwish was executed in Dammam, a city in the oil-rich Eastern Province.

Campaign group Reprieve said Saudi Arabia has now executed the same number of people in the first half of 2021 as it did in the whole of 2020

Saudi authorities last year said that they would no longer hand out death sentences to people who committed crimes while they were minors, and instead only apply a maximum 10-year jail sentence.

The royal decree said the new law would be applied retroactively to those awaiting execution.

Amnesty and Reprieve say al-Darwish's case should have been reviewed under the new law. They and other groups have repeatedly raised concerns about the implementation of this reform.

The UK's foreign secretary, Dominic Raab, also raised the issue of justice reform during a visit to Riyadh last month, according to the UK foreign office.

Earlier this year, the Saudi Human Rights Commission said the kingdom had "drastically" reduced the number of people it put to death in 2020.

However, Reprieve said Saudi Arabia had now executed the same number of people in the first half of 2021 as it did in the whole of 2020.

AMERICAN COLONY
(American) Samoa culture plays role in US citizenship ruling

American Samoa is the only unincorporated territory of the United States where the inhabitants are not American citizens at birth.

HONOLULU (AP) — In a decision citing American Samoa cultural traditions, those born in the U.S. territory shouldn't have citizenship automatically forced on them, a federal appeals court ruled Wednesday.

© Provided by The Canadian Press

The 10th U.S. Circuit Court of Appeals ruling reverses a lower court ruling that sided with three people from American Samoa who live in Utah and sued to be recognized as citizens. The judge ruled the Utah residents are entitled to birthright citizenship under the 14th Amendment. He then put his ruling on hold pending appeal.

U.S. Congress should play a bigger role than the courts in deciding citizenship for those in territories, the appeals court ruling said.

American Samoa is the only unincorporated territory of the United States where the inhabitants are not American citizens at birth.

Instead, those born in the cluster of islands some 2,600 miles (4,184 kilometers) southwest of Hawaii are granted “U.S. national” status, meaning they can’t vote for U.S. president, run for office outside American Samoa or apply for certain jobs. The only federal election they can cast a vote in is the race for American Samoa’s nonvoting U.S. House seat.

The ruling notes that American Samoa government leaders and others opposed the lawsuit because they are concerned automatic citizenship could disrupt cultural traditions, such as communal land ownership and social structures organized around large, extended families led by matai, those with hereditary chieftain titles.

“There is simply insufficient caselaw to conclude with certainty that citizenship will have no effect on the legal status of the fa’a Samoa,” or the American Samoan way of life, the ruling said. “The constitutional issues that would arise in the context of America Samoa’s unique culture and social structure would be unusual, if not entirely novel, and therefore unpredictable.”

Drawing on the views of the American Samoa people is one of the more gratifying aspects of the ruling, said Michael Williams, an attorney representing the American Samoa government, which intervened to oppose the lawsuit.

“It is also vindication for the principle that the people of American Samoa should determine their own status in accordance with Samoan culture and traditions,” he said.

A path toward U.S. citizenship exists for those who want it. But some say it’s costly and cumbersome. Non-citizen nationals of American Samoa are entitled to work and travel freely in the United States and receive certain advantages in the naturalization process.

Neil Weare, one of the attorneys representing the plaintiffs, said they are disappointed by the ruling, and are reviewing next steps. Options include asking a wider panel of appeals court judges to hear the case or taking it to the U.S. Supreme Court.

Weare is president of Equally American, which advocates for equality and civil rights for people in U.S. territories.

He said he was impressed with a dissenting judge’s opinion.

”When the Fourteenth Amendment was ratified, courts, dictionaries, maps, and censuses uniformly regarded territories as land ‘in the United States,’" wrote Judge Robert E. Bacharach in his dissent.

Self-determination is a highly valued principle in American Samoa, said Line-Noue Memea Kruse, adjunct faculty in Pacific islands studies at Brigham Young University-Hawaii and whose book is cited in the ruling.

“There are many foreign interests looming over these citizenship cases,” she said. "This is not the end. They will keep pushing. This to me is a form of inter-territorial hegemony."

Jennifer Sinco Kelleher , The Associated Press

CANADA
Green Party's Annamie Paul survives emergency meeting over leadership
David Thurton CBC

© Adrian Wyld/Canadian Press Green Party leader Annamie Paul survived an emergency meeting on her leadership Tuesday night. But the party's federal council adopted a separate motion asking Paul to publicly "repudiate" one of Paul's former senior advisors

The leadership of the Green Party's Annamie Paul is safe— for now — after party brass decided late Tuesday not to kickstart a process that could have ultimately ousted her as leader of the party.

The party's federal council – which is the governing body of the party – held an emergency meeting Tuesday night that lasted more than three-and-a-half hours. Officials were expected to hold a vote on whether to trigger a complex process under the party's constitution which could've declared no-confidence in Paul's leadership.

That vote did not end up taking place, multiple sources with knowledge of the meeting told CBC News.

Instead, sources say, the federal council adopted a separate motion asking Paul to publicly "repudiate" one of Paul's former senior advisors, Noah Zatzman, who accused many politicians — including unspecified Green MPs — of discrimination and anti-Semitism in a social media post last month.

The motion also calls for Paul to "explicitly support" the Green Party caucus. If not, the motion says, Paul would face a vote of non-confidence on July 20.

Tuesday night's decision follows a difficult few weeks for the party, which has been ripped apart by internal disputes over the Israeli-Palestinian conflict.

As violence in the region escalated, Paul issued a statement calling for a ceasefire and condemning both Palestinian rocket attacks and excessive Israeli military force, an apparent attempt to put forward a moderate position close to that of the Trudeau government.

© Guy LeBlanc/Radio-Canada Fredericton MP Jenica Atwin announced on Thursday that she is leaving the federal Green Party to sit as a Liberal.

Green MP Jenica Atwin — who has since left the Green caucus to join the Liberals — ripped into Paul's statement on Twitter. "It is a totally inadequate statement," Atwin wrote. "Forced evictions must end. I stand with Palestine and condemn the unthinkable air strikes in Gaza. End Apartheid."

 (SHE HAS RECANTED AND SINCE BECOME PRO ISRAEL AS PER THE LIBERAL PARTY POLICY)

Green MP Paul Manly also took issue with Paul's statement, saying the planned removal of Palestinian families from the East Jerusalem neighbourhood of Sheikh Jarrah "is ethnic cleansing."

Zatzman responded with a Facebook post stating that Greens "will work to defeat you and bring in progressive climate champions who are antifa and pro LGBT and pro indigenous sovereignty and Zionists!!!!!"

Zatzman is no longer an adviser to the leader. His six-month contract, slated to expire on July 4 and obtained by The Canadian Press, stipulates that the party will pay Zatzman a fee for time worked beyond 100 hours per month.

CBC News has reached out to the Green Party, Paul and Zatzman for comment following Tuesday's meeting.

Separately, two party executives recently announced they would step down early. One of them was John Kidder, a vice-president on the party's governing body and husband to MP and former leader Elizabeth May.

When Atwin announced last week that she was crossing the floor to join the Liberals, she said there were too many "distractions" in the Green Party and she wanted to work in a more "supportive and collaborative" environment.

In a media statement, May and B.C. Green MP Manly said they were "heartbroken" by Atwin's decision — and that Zatzman was to blame.

"Unfortunately, the attack against Ms. Atwin by the Green Party leader's chief spokesperson on May 14th created the conditions that led to this crisis," the two said. The MPs added that, while they were frustrated, they have "no intention of leaving the Green Party of Canada."

Speaking to reporters after Atwin's announcement, Paul said she was blindsided by her departure and only learned about it from media reports.

Paul said that while the party supports cross-party cooperation and rejects excessive partisanship, she said there are "significant differences" between the Green and Liberal parties and called Atwin's floor-crossing a "disappointment."

Paul said a byelection should be called in Fredericton because voters there chose to elect a Green MP in the 2019 campaign.

She said she doesn't believe the internal squabbling over Israel was what pushed Atwin to switch sides. She said she understands Atwin was in talks with the Liberals for "numerous weeks" before the internal debate over Middle East issues flared up.