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The science of sustainable drainage

Sustainable Drainage Systems map.

As the floods that struck Britain in early 2014 made all too clear, heavy rain can be bad news for homes, businesses and the environment. Tom Marshall found out how the British Geological Survey (BGS) is helping housebuilders control flooding while saving money.

 

The skies open and water gushes off roofs, down gutters and into drains. Heavy rain quickly overwhelms the drainage network; before long, water backs up and starts creeping towards buildings. In cities most of the ground is covered with concrete and tarmac, so the runoff can’t easily soak away.

Many UK drainage systems are old and connect to sewers, so torrential rain can send sewage sluicing into drains and eventually into rivers, killing fish en masse. On top of this ecological havoc, the sudden pulse of rainwater often makes watercourses burst their banks downstream.

This is all dangerous and costly; floods after heavy rain in 2007 left insurers facing an estimated £3.2 billion bill. The floods of early 2014 destroyed vital infrastructure and inundated at least 5,800 homes, at an average repair cost of £30,000-£40,000. Our changing climate is likely to make such extreme weather more common, and we need better ways of coping. One is a set of techniques known as Sustainable Drainage Systems – SuDS.

The key is slowing water down – diverting it into ponds and artificial wetlands or giving it time to soak into the ground (‘infiltration’) instead of discharging it directly to drains. The more water we can put into the soil, the less risk heavy rain will cause flooding. Even if this isn’t possible, water can be held in underground tanks and then released slowly.

Housebuilders use many of these techniques already, but new regulations mean their involvement needs to become more systematic. The Floods and Water Management Act took effect in 2010; this year or next Defra plans to release National Standards for Sustainable Drainage. The details aren’t yet certain, but local authorities are already setting up SuDS approval bodies.

The upshot is that runoff from a new housing development must now be no greater than from a greenfield site. That’s during an extreme storm, plus 30 per cent to allow for climate change. Developers must prioritise infiltration to deal with excess water, turning to alternatives only if it’s unworkable.

This all costs money. Developers must spend time planning and building effective drainage schemes that take up as little space as possible, to maximise housing density.

BGS gets involved during this planning phase, when developers are investigating whether infiltration SuDS are appropriate, and if so which kind. This depends on the soil and geology beneath. With permeable ground, promoting infiltration may just be a matter of diverting water into ponds or soakaways so it can be absorbed. On poorly-draining land, though, developers might need to install systems with a large surface area, such as permeable pavements, or with basins where water can be stored temporarily before infiltration.

Geological variation makes a big difference to the kind of drainage that’s appropriate. But until recently it was hard for developers to get a clear idea of ground conditions during the planning stage, before doing on-site tests. BGS researchers have produced a detailed Infiltration SuDS Map, bringing together 20 geological datasets to help the industry understand its drainage options.

Getting water into the ground

‘In theory you could get this information from a geological map,’ says Dr Rachel Dearden, a NERC Knowledge Exchange Fellow at BGS and head of the SuDS project. ‘But most developers don’t have the time or training to interpret these. We’re repackaging the information in a way that’s easy for the housebuilding industry to understand and act on.’

The maps are inexpensive – £1.50/km2 for the detailed version – and available over the internet. They let developers quickly narrow down their drainage options and highlight potential hazards from draining water into the ground. They’ll still need to do infiltration tests on site – but they get a headstart, beginning with more knowledge about the ground conditions.

This isn’t only useful to housebuilders; it also helps local authorities decide if the SuDS plans they submit will work and take account of all relevant issues, before approving them. After all, it is the authorities that have to maintain schemes after work finishes.

‘The first question for developers is “could draining water into the ground potentially cause major problems?” and they need an indication of the answer at an early stage,’ Dearden explains. If the site sits over soluble limestone bedrock, infiltration could create house-swallowing sinkholes. Likewise if nearby slopes are unstable, it could trigger landslides. If the water table is already high, adding more could risk groundwater flooding. Or if the ground level has been built up artificially with material from elsewhere, storing water in it could release potentially dangerous contaminants.

Their second question is ‘will the ground drain?’ Developers need to understand the permeability of the ground, the depth of the water table and whether the site is on a floodplain. They must also bear in mind the ground’s stability – is it compressible? Will it shrink and swell? If so, repeatedly wetting and drying it could weaken foundations.

Finally, the groundwater itself could be a problem. Do people ultimately drink it? If infiltration SuDS are being installed in an area covered by an Environment Agency Source Protection Zone, the developer needs to be careful before doing anything that could harm groundwater quality; they may need to filter the runoff with artificial wetlands or swales (shallow vegetated ditches). If any of these problems are present, the earlier they know the better.

For housebuilders, the move towards SuDS isn’t without advantages. It can often even be cheaper than traditional drainage – there’s less outlay on pipes, concrete and other artificial materials. And nobody wants to see flooding or poisoned fish due to badly-planned drainage.

Developers are increasing their use of SuDS ahead of the new regulations. But they need clear guidance on how to do this without major cost increases. Dearden has been working closely with housebuilders, meeting representatives and presenting at industry conferences to spread the word about how BGS data can help them comply with regulations economically. She’s also met numerous local authorities to discuss their plans for SuDS approval.

Steve Wielebski, chairman of the National Technical Committee at the Home Builders Federation, notes that the industry has long experience in managing runoff from built-up areas. ‘The concept behind SuDS is four thousand years old – it’s nothing new,’ he says.

‘Everyone agrees that if we can get water into the ground, we should do it,’ he adds. ‘But until recently housebuilders haven’t had good information to inform initial research into drainage for a site, and that’s why our members are finding the BGS data so very useful.’ This lets developers target investigations much more precisely, reducing the need for expensive on-site research. ‘There’s so much high-quality information available so cheaply that it’s beyond me why anyone wouldn’t make use of it,’ Wielebski says. ‘Rachel has done the industry proud in getting the word out about this.’

Note : The above story is based on materials provided by Natural Environment Research Council. The original article was written by Dr Rachel Dearden.

Is there organic matter on Mars?

Image of the Red Planet taken by the Mars Global Surveyor in 1999. Credit: NASA/JPL/MSSS

Organic matter recently detected by NASA’s robotic rover Curiosity is probably not due to contamination brought from Earth as researchers originally thought. A team of German and British scientists led by geoscientist Prof. Dr. Frank Keppler from Heidelberg University now suggests that the gaseous chlorinated organic compound — chloromethane — recently found on the Red Planet most likely comes from the soil of Mars, with its carbon and hydrogen probably deriving from meteorites that fell on the planet’s surface. This assumption is supported by isotope measurements made by the scientists in which they replicated some of the Mars lander experiments. In these investigations, samples from a 4.6 billion old meteorite that fell in Australia in 1969 were used.

Results from this study have been published in Scientific Reports.

The question of whether there is organic matter on Mars, an essential requirement for life on this planet, has been debated by the scientific community for a long time. To address this issue, the NASA Curiosity rover, which landed on Mars in August 2012, has conducted investigations on Martian soil. Upon heating soil samples simple organic molecules were detected and identified by on-board measurement systems. One of the substances detected was chloromethane, which contains carbon, hydrogen and chlorine atoms. In the opinion of the NASA experts, however, this compound could have been formed during the soil heating experiments by a reaction between perchlorates in Martian soil and an on-board chemical. Thus, even though the chlorine in the chloromethane comes from Mars, the carbon and hydrogen were considered to have been brought to Mars by the Curiosity rover. Interestingly this kind of organic material had also been identified in earlier experiments during the Viking mission in 1976, but the compound was considered a terrestrial contaminant.

The German-British team of scientists led by Prof. Keppler has investigated whether there could be another explanation for the observations of chloromethane on Mars. They assumed that the gaseous chlorinated organic compound is indeed derived from Martian soil, but that its carbon and hydrogen are provided by meteorites. To support their hypothesis, the researchers examined samples from a 4.6 billion years old meteorite that fell on earth in 1969 near the Australian city of Murchison. According to Prof. Keppler this meteoritic material contains two per cent carbon. Space experts assume that a relatively large amount of micrometeorites with a similar composition to the one of Murchison fall on the surface of Mars each year.

When Frank Keppler and his colleagues heated the Murchison meteoritic matter in the presence of chlorine they observed chloromethane. “The ratio of heavy to light carbon and hydrogen atoms, known as the isotopic fingerprint of a gas, clearly shows that the organic material has an extraterrestrial origin,” Prof. Keppler says. The scientists transferred their results to Martian surface conditions which receive meteorites of similar composition. “Hence chloromethane which was found by the two separate Mars missions could be formed by the Martian soil, and the carbon and hydrogen would have their origin in the micrometeorites that rain down on Mars,” explains Prof. Keppler. “However, it cannot be ruled out that microorganisms which might have been living on the planet some time ago might have provided a fraction of the organic matter.” The Heidelberg scientist assumes that in future Mars missions the isotopic fingerprint of the chloromethane could determine whether its origin is from organic material that is indigenous to Mars, was deposited by meteorites or is contamination from the landers sent from Earth.

Frank Keppler leads the Biogeochemistry working group at Heidelberg University’s Institute of Earth Sciences. In addition to scientists from Heidelberg, experts from the Max Planck Institute of Chemistry in Mainz and the School of Biological Sciences at Queen’s University in Belfast contributed to this research.

Reference:
F. Keppler, D.B. Harper, M. Greule, U. Ott, T. Sattler, G.F. Schöler & J.T.G. Hamilton. Chloromethane release from carbonaceous meteorite affords new insight into Mars lander findings. Scientific Reports, 2014 DOI: 10.1038/srep07010

Note : The above story is based on materials provided by Heidelberg University.

Yarlung Tsangpo River

Map of the Yarlung Tsangpo River

The Yarlung Tsangpo is the part of Brahmaputra River that flows through Tibet, known by its Tibetan name. It originates at Angsi Glacier in western Tibet southeast of Mount Kailash and Lake Manasarovar. It later forms the South Tibet Valley and Yarlung Tsangpo Grand Canyon before passing through the state of Arunachal Pradesh, India, where it is known as Siang.It is sometimes called Yarlung Zangbo or Yarlung Zangbo Jiang . The part Tsangpo denotes a river flowing from or through Tsang, meaning Tibet west of Lhasa.

Downstream from Arunachal Pradesh the river becomes wider and at this point is called the Siang. After reaching Assam, the river is known as Brahmaputra. From Assam, the river enters Bangladesh at Ramnabazar. From there until about 200 years ago it used to flow eastward and joined the Meghna River near Bhairab Upazila. This old channel has been gradually dying now. At present the main channel of the river is called Jamuna River, which flows southward to meet Ganges, which in Bangladesh is called the Padma.

When leaving the Tibetan Plateau, the Yarlung River flows in the world’s largest and deepest canyon, Yarlung Tsangpo Grand Canyon. The gorge has been described as “the highest river in the world” by the organizers of a kayaking expedition, although it’s not clear from their press release what definition was used.

Description

The Yarlung Tsangpo River is the highest major river in the world. Its longest tributary is the Nyang River. In Tibet the river flows through the South Tibet Valley, which is approximately 1,200 kilometres (750 mi) long and 300 kilometres (190 mi) wide. The valley descends from 4,500 metres (14,800 ft) above sea level to 3,000 metres (9,800 ft). As it descends, the surrounding vegetation changes from cold desert to arid steppe to deciduous scrub vegetation. It ultimately changes into a conifer and rhododendron forest. The tree line is approximately 3,200 metres (10,500 ft).Sedimentary sandstone rocks found near the Tibetan capital of Lhasa contain grains of magnetic minerals that record the Earth’s alternating magnetic field current.

The basin of the Yarlung River, bounded by the Himalayas in the south and Kang Rinpoche and Nyenchen Tanglha Mountains in the north, has less severe climate than the more northern (and higher-elevation) parts of Tibet, and is home to most of the Autonomous Region’s population (Lhasa City, Shigatse, Lhoka, and Nyingchi Prefectures).

The Yarlung Tsangpo Grand Canyon, formed by a horse-shoe bend in the river where it leaves the Tibetan Plateau and flows around Namcha Barwa, is the deepest, and possibly longest canyon in the world. The river has been a challenge to whitewater kayakers because of the extreme conditions of the river.

The Yarlung Tsangpo River has three major waterfalls. The largest waterfall of the river, the “Hidden Falls”, was not publicized in the West until 1998, when its sighting by Westerners was briefly hailed as a “discovery.” They were even portrayed as the discovery of the great falls which had been the topic of stories told to early Westerners by Tibetan hunters and Buddhist monks, but which had never been found by Western explorers at the time. Chinese authorities protested, however, saying that Chinese geographers, who had explored the gorge since 1973, had already taken pictures of the falls in 1987 from a helicopter.

Note : The above story is based on materials provided by Wikipedia

Leaping lizards!

High-speed video footage of leaping lizards supports a 40-year-old hypothesis about how theropod dinosaurs, like the velociraptors of Jurassic Park fame, adjusted the angle of their tails to stay stable when jumping.

Source : Nature Video

Mars, too, has macroweather

A global mosaic of Mars from the Viking mission. Credit: NASA/JPL

Weather, which changes day-to-day due to constant fluctuations in the atmosphere, and climate, which varies over decades, are familiar. More recently, a third regime, called “macroweather,” has been used to describe the relatively stable regime between weather and climate.

A new study by researchers at McGill University and UCL finds that this same three-part pattern applies to atmospheric conditions on Mars. The results, published in Geophysical Research Letters, also show that the sun plays a major role in determining macroweather.

The research promises to advance scientists’ understanding of the dynamics of Earth’s own atmosphere — and could provide insights into the weather of Venus, Saturn’s moon Titan, and possibly the gas giants Jupiter, Saturn, Uranus and Neptune.

The scientists chose to study Mars for its wealth of data with which to test their theory that a transitional “macroweather” regime exists on other planets. They used information collected from Viking — a Mars lander mission during the 1970s and 1980s — and more recent data from a satellite orbiting Mars.

By taking into account how the sun heats Mars, as well as the thickness of the planet’s atmosphere, the scientists predicted that Martian temperature and wind would fluctuate similarly to Earth’s — but that the transition from weather to macroweather would take place over 1.8 Martian days (about two Earth days), compared with a week to 10 days on Earth.

“Our analysis of the data from Mars confirmed this prediction quite accurately,” said Shaun Lovejoy, a physics professor at McGill University in Montreal and lead author of the paper. “This adds to evidence, from studies of Earth’s atmosphere and oceans, that the sun plays a central role in shaping the transition from short-term weather fluctuations to macroweather.” The findings also indicate that weather on Mars can be predicted with some skill up to only two days in advance, compared to Earth’s 10 days.

Co-author Professor Jan-Peter Muller from the UCL Mullard Space Science Laboratory, said: “We’re going to have a very hard time predicting the weather on Mars beyond two days given what we have found in weather records there, which could prove tricky for the European lander and rover!”

Reference:
Shaun Lovejoy, J.-P. Muller, J. P. Boisvert. On Mars too expect macroweather. Geophysical Research Letters, 2014; DOI: 10.1002/2014GL061861

Note : The above story is based on materials provided by McGill University.

Rocky Mountain storms lead to new findings about hailstones

Rocky Mountains. Credit: Public Domain

Hailstones from three Rocky Mountain storms formed around biological material, then bounced around the clouds picking up layers of ice, according to a new Montana State University study.

 

The discovery of a biological embryo extends previous findings about the formation of snow and rain, applies to hailstones globally and provides basic information about a little-studied topic, said the researchers who published their findings Nov. 6 in the Journal of Geophysical Research: Atmospheres.

“This is the first paper to really show that biological material makes hailstones,” said John Priscu, a renowned polar scientist and professor in MSU’s Department of Land Resources and Environmental Sciences. “Despite the millions in dollars of damage the storm caused in Bozeman (Mont.), the damaging hailstones provided us with a better understanding of hailstone formation, which will help us understand the role of aerosol particles in the formation of precipitation.”

Alex Michaud – MSU doctoral student and first author of the paper—normally studies Antarctic microorganisms with Priscu, but he took on a side project after hailstones pummeled Bozeman, Mont., on June 30, 2010.

“If it weren’t for his inquisitive nature of how things work, no good would have come from the devastating storm,” Priscu said.

Once the storm subsided, Michaud collected hailstones and stored them in an MSU freezer at minus 22 degrees Fahrenheit. The hailstones averaged 1.5 inches in diameter. Then Michaud gathered hailstones from two more area storms that occurred in 2010 and 2011. Those averaged about half an inch in diameter.

Examining some 200 hailstones in MSU’s Subzero Science and Engineering Research Facility showed that the hailstones formed around a biological embryo, Michaud said. Analyzing stable isotopes of water in an Ohio State University laboratory showed that most of the hailstone embryos froze at relatively warm temperatures, generally above 6.8 degrees Fahrenheit, which corroborates freezing temperatures of biological embryos recovered from the middle of hailstones.

Two different research methods showed that a warm temperature of ice nucleation indicates biological material is the likely nuclei, Michaud said. He added that hailstones grow in such a way that makes them a nice model system for studying atmospheric ice nucleation and cloud processes.

Among those providing direction and advice to Michaud were Priscu and David Sands, both co-authors on the published paper and internationally known researchers.

Priscu was chief scientist and one of three directors of a historic U.S. expedition that drilled through half a mile of Antarctic ice and found microorganisms living in a subglacial lake in January 2013. Michaud was part of the Whillans Ice Stream Subglacial Access Research Drilling project (WISSARD) and is about to head to Antarctica for its next phase.

Sands, a professor in MSU’s Department of Plant Sciences and Plant Pathology, conducted and published previous research that gained widespread attention for showing that active airborne bacteria were involved in the formation of rain and snow over several continents. Michaud’s hailstone study builds upon his work.

Co-author John Dore, associate research professor in MSU’s Department of Land Resources and Environmental Sciences, conducted low-level phosphate analyses to validate hailstone decontamination procedures. The presence of phosphates indicates contamination that originated on the ground. Dore also analyzed stable isotope data and developed temperature calibrations for the hailstone layer formation, and participated in many discussions about hail and how the research pieces fit together.

Co-authors outside of MSU were Deborah Leslie and W. Berry Lyons in the School of Earth Sciences and Byrd Polar Research Center at The Ohio State University. Lyons is a long-time collaborator of Priscu’s, and Leslie received her Ph.D. in Lyons’ lab. She analyzed stable isotopes from the melted hailstone embryos to estimate the temperatures that the hailstone embryos froze in the clouds.

In addition to his co-authors, Michaud said former MSU postdoctoral researcher Brent Christner and MSU affiliate Cindy Morris provided important assistance by helping him develop ideas and discuss data. Christner is also part of the WISSARD project. Morris collaborated with Sands on previous research about the formation of rain and snow.

Michaud also consulted with fellow hailstone researcher Tina Santl Temkiv, a postdoctoral researcher at Aarhus University in Denmark. She is in the university’s Department of Bioscience where Michaud was last spring through the National Science Foundation’s Integrative Graduate Education and Research Traineeship (IGERT) program.

“It was very coincidental that she published two hailstone microbiology papers two years before me and we ended up at the same university for a few months. Plus, we are the only ones to work on hailstone microbiology since a 1973 paper in Nature,” Michaud said, noting that the two jokingly established the first hailstone microbiology research center at Aarhus.

Reference: 
Alexander B. Michaud et al: Biological ice nucleation initializes hailstone formation. Journal of Geophysical Research: Atmospheres 2014; DOI: 10.1002/2014JD022004

Note : The above story is based on materials provided by Montana State University

Clues to one of Earth’s oldest craters revealed

Clouds over Australia are shown. Credit: NASA

The Sudbury Basin located in Ontario, Canada is one of the largest known impact craters on Earth, as well as one of the oldest due to its formation more than 1.8 billion years ago.

Researchers who took samples from the site and subjected them to a detailed geochemical analysis say that a comet may have hit the area to create the crater.

“Our analysis revealed a chondritic platinum group element signature within the crater’s fallback deposits; however, the distribution of these elements within the impact structure and other constraints suggest that the impactor was a comet. Thus, it seems that a comet with a chondritic refractory component may have created the world-famous Sudbury basin,” said Joe Petrus, lead author of the Terra Nova paper.

Reference: DOI: 10.1111/ter.12125

Note : The above story is based on materials provided by Wiley

Latrines, sewers show varied ancient Roman diet

In this undated photo provided by Mark Robinson, environmental archeologist at Oxford University Museum of Natural History, a scallop shell with makeup found in a sewer of Herculaneum. Archaeologists picking through latrines, sewers, cesspits and trash dumps at Pompeii and Herculaneum have flushed out tantalizing clues to what appears to be a varied diet in those ancient Roman cities destroyed in 79 A.D. by the eruption of Vesuvius. Much of what the inhabitants of those doomed towns didn’t digest or left on their plates became traces lining toilet pipes, remnants in centuries-long buildup in cesspits, or throwaway in dumps. At a three-day conference ending Friday in Rome, archaeologists discussed their discoveries, including gnawed-on fish bones, goose eggshells from meals of the elite and carbonized nibbles baked perhaps as offerings for deities. (AP Photo/Mark Robinson/Oxford University Museum of Natural History)

Archaeologists picking through latrines, sewers, cesspits and trash dumps at Pompeii and Herculaneum have found tantalizing clues to an apparently varied diet there before the eruption of Mount Vesuvius destroyed those Roman cities in 79 A.D.

Much of what residents didn’t digest or left on their plates went down into latrine holes, became remnants in cesspits built up over the centuries or was thrown away in local dumps. At a three-day conference ending Friday in Rome, archaeologists discussed their discoveries, including gnawed-on fish bones and goose eggshells that were possibly ancient delicacies for the elite.

“We just have small glimpses of the environment, but some are quite curious,” Mark Robinson, a professor of environmental archaeology at Oxford University Museum of Natural History, told the conference.

Here’s some of the curiosities the experts discussed:

ROMANS LIKED EATING LOCAL

Much of what the inhabitants ate was local. Archaeologists noted that some types of mollusk shells found in the sewers of Herculaneum came from the ancient town’s beach. Notable exceptions include grain, which was likely imported from Egypt; dates from the Middle East and northern Africa; and pepper spice from India. Although flour left no traces across such a long time, grain weevils apparently survived the milling process, ending up in a Herculaneum sewer that served a block of shops and home.

PORK PLEASED ROMAN PALATES THEN AND NOW

Today’s Romans are big on pork—pork slices known as porchetta are a popular filling for lunchtime sandwiches. Trash dumps from roughly the 1st century B.C. and the early 1st century A.D. in the Pompeii neighborhood of Porta Stabia yielded an abundance of pig bones, a sure sign that pork was popular then, noted Michael MacKinnon from the University of Winnipeg. Particularly tasty mollusks known as telline were popular on ancient tables; now telline as an ingredient for a seafood sauce is a much sought-after item on present-day Roman menus.

A CHICKEN IN EVERY POT?

That’s not clear but lots of chicken eggs were consumed, judging by the numerous pieces of eggshell found. Erica Rowan, an archaeologist at the University of Exeter who worked on the Herculaneum sewer, also reported finding two fragments of goose egg shell, possibly the remnants of a meal consumed by the elite. But for the most part, it appeared that both rich and not-so-rich Romans in these cities ate much the same food, especially fish.

HORS D’OEUVRES FOR THE DEITIES

Being buried for centuries in the sewers and cesspits helped preserve food traces—Vesuvius’ eruption also carbonized some food for posterity. Bite-sized, carbonized, cake-like breads—”nibbles for the gods” is how Robinson referred to them—were discovered at a disused kiln in Pompeii. Pieces of votive cups were also found, prompting archaeologists to view the nibbles as possible offerings to ancient Roman deities.

ANCIENT RECYCLING

Robinson also reported finding a scallop shell that held rouge, serving as a kind of women’s compact.

Note : The above story is based on materials provided by © 2014 The Associated Press. All rights reserved.

Seismic Hazard in the Puget Lowland, Washington State, USA

Figure 1 from Personius et al.

Boulder, Colo., USA – Seismic hazards in the Puget Lowland of northwestern Washington include deep earthquakes associated with the Cascadia subduction zone and shallow earthquakes associated with crustal faults across the region. Research presented in Geosphere this month establishes not only that one of the more prominent crustal faults, the Darrington-Devils Mountain fault zone, displays evidence of strong earthquakes in the past, but that it will likely be a source of strong earthquakes in the future.

Paleoseismic investigations on the Darrington-Devils Mountain fault zone by Stephen F. Personius and colleagues, using three-dimensional trenching, document a large-magnitude (M 6.7 to 7.0) earthquake about 2,000 years ago and show evidence of a similar earthquake about 8,000 years ago.

An additional surprising result is evidence indicating that the sense of slip on the fault zone during these earthquakes was primarily right-lateral, with a smaller component of north-side-up vertical slip. Holocene north-side-up, right-lateral oblique slip is opposite the south-side-up, left-lateral oblique sense of slip inferred from deformation of Eocene and older rocks along the fault zone. According Personius and colleagues, the cause of this slip reversal is unknown, but may be related to ongoing clockwise rotation of northwestern Washington State into a position more favorable to right-lateral slip in the current stress field.

Note : The above story is based on materials provided by The Geological Society of America

Lava continues to flow toward Hawaii’s Pahoa “Video”

Lava flowing from the Kilauea volcano in Hawaii slows but continues to threaten the village of Pahoa. Rough Cut

Video Source: Reuters

140-million-year-old dinosaur tooth found in Malaysia

Associate Professor Department of Geology, Dr. Masatoshi Sone shows a fossil tooth of an Ornithischian dinosaur at the University of Malaya in Kuala Lumpur on November 13, 2014
Associate Professor Department of Geology, Dr. Masatoshi Sone shows a fossil tooth of an Ornithischian dinosaur at the University of Malaya in Kuala Lumpur on November 13, 2014

While still unsure of the exact species of dinosaur, lead researcher Masatoshi Sone from the University of Malaya said the discovery means “it is plausible that large dinosaur fossil deposits still remain in Malaysia”.

“We started the programme to look for dinosaur fossils two years ago. We are very excited to have found the tooth of the dinosaurian order called Ornithischian in central Pahang state” last year, he said.

Researchers from Japan’s Waseda University and Kumamoto University also took part in the project.

Ornithischian, or “bird-hipped”, is a major group comprised of herbivous dinosaurs such as triceratops.

The dinosaur would have been about as big as a horse, Sone said.

The darkened tooth fossil—13-mm-long (0.5-inches) and 10.5-mm-wide—was discovered in a sedimentary rock formation by a team of Malaysian and Japanese palaeontologists.

It was found close to where the first Malaysian dinosaur fossil, estimated to be at least 75 million years old, was discovered in 2012.

That fossil was found to belong to a fish-eating predator belonging to the family of dinosaur known as Spinosaurid, believed to be semi-aquatic.

The exact location of the discoveries is being kept secret in order to preserve it.

Note : The above story is based on materials provided by AFP

Blowholes and caves surprise on Nullarbor geological survey

"When the pilot spotted a blowhole, he marked the position with a GPS for the ground team to physically verify and accurately locate," Dr Burnett says.Image: spelio
“When the pilot spotted a blowhole, he marked the position with a GPS for the ground team to physically verify and accurately locate,” Dr Burnett says.Image: spelio

La Trobe University expert says Dr Shannon Burnett says he had always thought of the Nullabor Plain as “just a big desert”.

“However, as I started studying and collecting data for my honors project in 2011, I became intrigued as flank margin caves [forming on margins of enclosing ridges] are normally found on islands, but this is the first time they have been found on a continental setting,” he says.

Dr Burnett has been gathering data on the region’s blowholes with the help of the Victorian Speleological Society.

They carried out aerial surveys and subsequent ground confirmation expeditions and also considered data collected from previous surveys carried out by the Western Australian Cavers.

Dr Burnett found the blowholes in two bands, one along the coast and the other about 75km inland, in a 25−30km wide band incorporating 1,307 features.

He believes the cave porosity is much greater than the blowhole density because the blowholes blow draughts of up to 70km/h indicating they are connected by extensive cave systems of small un-enterable passages.

He says the blowhole draughts are caused by barometric pressure and not tidal influences.

Air survey uncovers blowholes

“We chose areas to survey that we believed had a high density of features or had one or more significant features,” Dr Burnett says.

“I had the use of a retired pilot with an ultra-light aircraft who flew in a systematic pattern so that the whole search area could be covered.

“When the pilot spotted a blowhole, he marked the position with a GPS for the ground team to physically verify and accurately locate.

“Because of accessibility issues on the Nullarbor, previous data [was] biased around roads and the Trans-Continental railway, however the systematic coverage of the large and defined search areas by the ultra-light aircraft has almost eliminated bias.”

Dr Burnett says it was too difficult to access and explore the Nullarbor’s northern regions and satellite imagery wasn’t an option as he didn’t have the budget for paid satellite imagery and the blowholes are too small to be seen on free satellite services.

He says more surveys and expeditions will be conducted, especially as these flank margin caves represent an unrecognised potential petroleum reservoir.

Note : The above story is based on materials provided by Science Network WA

Raw: Lava Burns on Local Hawaii Road

Video from the Big Island of Hawaii shows lava from the Kilauea Volcano burning on a local road. The lava’s leading edge remains 500 feet from Pahoa Village Road. However, several lobes of lava broke out and advanced on Sunday. (Nov. 10)

Video provided by AP

Understanding the 1989 Loma Prieta Earthquake in an Urban Context

Figure 5 from Kevin M. Schmidt et al.
Figure 5 from Kevin M. Schmidt et al.

Despite the absence of primary surface rupture from the 1989 Loma Prieta earthquake, patterns of damage to pavement and utility pipes can be used to assess ground deformation near the southwest margin of the densely populated Santa Clara or “Silicon” Valley, California, USA. Schmidt and colleagues utilized more than 1,400 damage sites as an urban strain gage to determine relationships between ground deformation and previously mapped faults.

Post-earthquake surveys of established monuments and the concrete channel lining of Los Gatos Creek reveal belts of deformation consistent with regional geologic structure. The authors conclude that reverse movement largely along preexisting faults, probably enhanced significantly by warping combined with enhanced ground shaking, produced the widespread ground deformation.

Such damage, with a preferential NE-SW sense of shortening, occurred in response to the 1906 and 1989 earthquakes and will likely repeat itself in future earthquakes in the region.

Note : The above story is based on materials provided by  The Geological Society of America

Volcano hazards and the role of westerly wind bursts in El Niño

tectonic-plate-mystery-geologypage
On June 27, lava from Kīlauea, an active volcano on the island of Hawai’i, began flowing to the northeast, threatening the residents in a community in the District of Puna. Credit: USGS

On 27 June, lava from Kīlauea, an active volcano on the island of Hawai`i, began flowing to the northeast, threatening the residents in Pāhoa, a community in the District of Puna, as well as the only highway accessible to this area. Scientists from the U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) and the Hawai`i County Civil Defense have been monitoring the volcano’s lava flow and communicating with affected residents through public meetings since 24 August. Eos recently spoke with Michael Poland, a geophysicist at HVO and a member of the Eos Editorial Advisory Board, to discuss how he and his colleagues communicated this threat to the public.

Drilling a Small Basaltic Volcano to Reveal Potential Hazards

Drilling into the Rangitoto Island Volcano in the Auckland Volcanic Field in New Zealand offers insight into a small monogenetic volcano, and may improve understanding of future hazards.

From AGU’s journals: El Niño fades without westerly wind bursts

The warm and wet winter of 1997 brought California floods, Florida tornadoes, and an ice storm in the American northeast, prompting climatologists to dub it the El Niño of the century. Earlier this year, climate scientists thought the coming winter might bring similar extremes, as equatorial Pacific Ocean conditions resembled those seen in early 1997. But the signals weakened by summer, and the El Niño predictions were downgraded. Menkes et al. used simulations to examine the differences between the two years.

The El Niño-Southern Oscillation is defined by abnormally warm sea surface temperatures in the eastern Pacific Ocean and weaker than usual trade winds. In a typical year, southeast trade winds push surface water toward the western Pacific “warm pool”–a region essential to Earth’s climate. The trade winds dramatically weaken or even reverse in El Niño years, and the warm pool extends its reach east.

Scientists have struggled to predict El Niño due to irregularities in the shape, amplitude, and timing of the surges of warm water. Previous studies suggested that short-lived westerly wind pulses (i.e. one to two weeks long) could contribute to this irregularity by triggering and sustaining El Niño events.

To understand the vanishing 2014 El Niño, the authors used computer simulations and examined the wind’s role. The researchers find pronounced differences between 1997 and 2014. Both years saw strong westerly wind events between January and March, but those disappeared this year as spring approached. In contrast, the westerly winds persisted through summer in 1997.

In the past, it was thought that westerly wind pulses were three times as likely to form if the warm pool extended east of the dateline. That did not occur this year. The team says their analysis shows that El Niño’s strength might depend on these short-lived and possibly unpredictable pulses.

Note : The above story is based on materials provided by American Geophysical Union

‘Dark magma’ could explain mystery volcanoes

The structure of Earth's interior, showing the solid inner core and molten outer core and the surrounding mantle. Hot plumes of rock rise from the base of the mantle and erupt on the surface at hot spots like Iceland. © Johan Swanepoel/iStockphoto/Thinkstock
The structure of Earth’s interior, showing the solid inner core and molten outer core and the surrounding mantle. Hot plumes of rock rise from the base of the mantle and erupt on the surface at hot spots like Iceland. © Johan Swanepoel/iStockphoto/Thinkstock

“It’s a very provocative paper … a bit speculative,” says Thomas Duffy, a geoscientist at Princeton University who was not involved with the study. “But it’s taking us in an important step on the road to understanding the deep Earth.”

Most volcanoes form because tectonic plates, vast sections of Earth’s crust, smash against or slide underneath each other. The pushing and melting there feed the volcanoes in the infamous Ring of Fire around the Pacific Ocean. But hot spot–spawned volcanoes like Hawaii’s are a different breed. They are nowhere near tectonic plate edges, and yet millions of years ago they spewed out so much lava that they nearly blanketed whole continents with molten rock or covered the globe with soot. Geologists believe the source of this magma is coming from just above Earth’s outer core, but they’re not exactly sure how.

Alexander Goncharov, a geophysicist at the Carnegie Institution for Science in Washington, D.C., and colleagues think that there are patches of magma—remnants from an early molten stage of our planet’s history—quilted around the outer core. Because the bottom of Earth’s mantle is nearly 3000 kilometers below the surface—about a 3-day journey if you could drive there by car—temperatures and pressures reach such hellish extremes that the atomic structures of these magmas are different from those they would have at lesser pressures. Duffy says that “can really change physical properties a lot,” including the way the material looks and absorbs heat.

To test how magma might behave near the core, Goncharov and his colleagues squeezed a sliver of a dark, opaque glass, made from iron and silicate to mimic the composition of deep Earth magmas, between two diamonds to simulate pressures near the core. The team then shined an infrared light through the glass and measured how much light passed through. As the pressure increased, so did the amount of light the glass absorbed, and the team saw a change in the atomic structure of the glass, the researchers report online today in Nature Communications.

Goncharov says that means magmas at high pressures in the lower mantle must be sponging up heat emanating from the core. As these patches of magma around the core get hotter, they start to act as a door for heat to pass into the mantle by convection. The heated mantle rocks then move up through the planet in a massive plume until they erupt on the surface, creating large volcanoes in strange places like Hawaii, Yellowstone, Easter Island, and Mount Etna, and some of the most violent eruptions.

If the team is right, its work could illuminate a key part of Earth’s geology. Duffy says these plumes are “one of the most important things to understand,” because the movement of heat powers many processes on the planet. For one, Earth’s magnetic field depends on how the core spins and flows inside the planet. As a result, Duffy says, “the way heat flows from the core to the mantle could potentially affect the way Earth’s magnetic field evolves over time.”

Not everybody is ready to get behind Goncharov and his colleagues’ new hypothesis. “There are two fundamental limitations of the paper,” Duffy says. “First that they’re studying a glass and not [melted rock], and there’s the fact that [the experiment] is at room temperature and not high temperature.” Until scientists perform the experiment with molten rock heated to about 3200°C, Duffy says, they can’t be sure how the magma really behaves.

And geologists still contest whether the pockets of magma around Earth’s outer core actually exist. To probe Earth’s interior, scientists rely on seismic waves from large earthquakes that have to travel through 3000 kilometers of rock. At that depth, the measurements become “a little bit ambiguous,” Duffy says. “And there’s a question as to why the liquid wouldn’t just all drain [away].” Because these dark magma pockets float above the core, it’s a bit like imagining an ocean rising tens of kilometers above sea level. “It’s not impossible,” he says, “but the idea that there’s melt in the deep
mantle is controversial.”

Reference:
Motohiko Murakami,Alexander F. Goncharov,Naohisa Hirao,Ryo Masuda,Takaya Mitsui,Sylvia-Monique Thomas& Craig R. Bina , http://dx.doi.org/10.1038/NCOMMS6428

Note: The above story is based on materials provided by American Association for the Advancement of Science. The original article was written by Angus Chen.

Kīlauea, 1790 and today

The Island of Hawai'i, USA. Credit: Image courtesy NASA.
The Island of Hawai’i, USA. Credit: Image courtesy NASA.

The footprints, made by warriors and their families, appear along a major trail in use at the time. Today, the area is one of the most visited parts of Hawai’i Volcanoes National Park.

The explosive eruption resulted from the violent interaction of groundwater with hot rocks. Such explosive eruptions have happened frequently in Kīlauea’s past and will probably occur in the future when the caldera collapses down to the water table, some 600 m (2000 ft) below the summit of the volcano.

The 1790 eruption of Kīlauea was explosive, and its major impacts were in the summit area of the volcano. The eruption taking place now at Kīlauea is effusive, says Swanson, producing a flow of lava that erupts without explosion. This flow is erupting from a site named Pu’u ‘Ō’ō on the east rift zone, far from the summit area, and lava has to flow many kilometers (several miles) before reaching inhabited areas.

Explosive eruptions are very hazardous; the 1790 fatalities bear witness to this fact. Lava flows are not very hazardous to life but can be exceedingly destructive to property. Explosive eruptions are brief but terrifying. Lava flows often last for months or more and are captivating to the viewer. Kīlauea has both types of eruptions, but not at the same time.

Violent explosive eruptions from the summit of Kīlauea are geologically common. They are generally clustered into periods lasting a few centuries. It has been about 200 years since the most recent major explosion, which culminated about 300 years of frequent explosive eruptions. In the past 200 years, Kīlauea has produced many lava flows similar to the present one; small explosions took place in 1924 and, on an even smaller scale, during the past 6 years.

The general public is unaware of Kīlauea’s explosive nature, because the volcano has erupted mainly lava flows in recent times. Kīlauea will almost certainly become explosive at some future time, producing conditions similar to those of 1790. However, according to Swanson, there is no reason to think that a period of violent eruptions will resume any time soon. The public can probably expect more lava flows in the near future, such as those of the past three decades from Pu’u ‘Ō’ō.

Reference:
D. A. Swanson, S. J. Weaver, B. F. Houghton. Reconstructing the deadly eruptive events of 1790 CE at K lauea Volcano, Hawai’i. Geological Society of America Bulletin, 2014; DOI: 10.1130/B31116.1

Note : The above story is based on materials provided by Geological Society of America.

Archaeologists discover remains of Ice Age infants in Alaska

University of Alaska Fairbanks professors Ben Potter and Josh Reuther excavate the burial pit at the Upward Sun River site. Credit: UAF photo courtesy of Ben Potter

The remains of two Ice Age infants, buried more than 11,000 years ago at a site in Alaska, represent the youngest human remains ever found in northern North America, according to a new paper published in the Proceedings of the National Academy of Sciences.

The site and its artifacts provide new insights into funeral practices and other rarely preserved aspects of life among people who inhabited the area thousands of years ago, according to Ben Potter, a researcher at the University of Alaska Fairbanks and the paper’s lead author.

Potter led the archaeological team that made the discovery in fall of 2013 at an excavation of the Upward Sun River site, near the Tanana River in central Alaska. The researchers worked closely with local and regional Native tribal organizations as they conducted their research. The National Science Foundation funded the work.

Potter and his colleagues note that the human remains and associated burial offerings, as well as inferences about the time of year the children died and were buried, could lead to new thinking about how early societies were structured, the stresses they faced as they tried to survive, how they treated the youngest members of their society, and how they viewed death and the importance of rituals associated with it.

Potter made the new find on the site of a 2010 excavation, where the cremated remains of another 3-year-old child were found. The bones of the two infants were found in a pit directly below a residential hearth where the 2010 remains were found.

“Taken collectively, these burials and cremation reflect complex behaviors related to death among the early inhabitants of North America,” Potter said.

In the paper, Potter and his colleagues describe unearthing the remains of the two children in a burial pit under a residential structure about 15 inches below the level of the 2010 find. The radiocarbon dates of the newly discovered remains are identical to those of the previous find–about 11,500 years ago–indicating a short period of time between the burial and cremation, perhaps a single season.

Also found within the burials were unprecedented grave offerings. They included shaped stone points and associated antler foreshafts decorated with abstract incised lines, representing some of the oldest examples of hafted compound weapons in North America.

“The presence of hafted points may reflect the importance of hunting implements in the burial ceremony and with the population as whole,” the paper notes.

The researchers also examined dental and skeletal remains to determine the probable age and sex of the infants at the time of the death: One survived birth by a few weeks, while the other died in utero. The presence of three deaths within a single highly mobile foraging group may indicate resource stress, such as food shortages, among these early Americans.

Such finds are valuable to science because, except in special circumstances like those described in the paper, there is little direct evidence about social organization and mortuary practices of such early human cultures, which had no written languages.

The artifacts–including the projectile points, plant and animal remains–may also help to build a more complete picture of early human societies and how they were structured and survived climate changes at the end of the last great Ice Age. The presence of two burial events–the buried infants and cremated child–within the same dwelling could also indicate relatively longer-term residential occupation of the site than previously expected.

The remains of salmon-like fish and ground squirrels in the burial pit indicate that the site was likely occupied by hunter-gatherers between June and August.

“The deaths occurred during the summer, a time period when regional resource abundance and diversity was high and nutritional stress should be low, suggesting higher levels of mortality than may be expected give our current understanding” of survival strategies of the period, the authors write.

Reference:
Ben A. Potter, Joel D. Irish, Joshua D. Reuther, and Holly J. McKinney. New insights into Eastern Beringian mortuary behavior: A terminal Pleistocene double infant burial at Upward Sun River. PNAS, November 10, 2014 DOI: 10.1073/pnas.1413131111

Note : The above story is based on materials provided by University of Alaska Fairbanks. The original article was written by Marmian Grimes.

Discovery of a dinosaur tail in northern Mexico

A team of paleontologists have discovered the fossilized remains of a 72 million-year-old dinosaur tail in a desert in northern Mexico. It’s the first ever found in the country.

Source: AFP

A/C came standard on armored dinosaur models

Ankylosaurs

Berlin, Germany (November, 2014) – Sweating, panting, moving to the shade, or taking a dip are all time-honored methods used by animals to cool down. The implicit goal of these adaptations is always to keep the brain from overheating. Now a new study shows that armor-plated dinosaurs (ankylosaurs) had the capacity to modify the temperature of the air they breathed in an exceptional way: by using their long, winding nasal passages as heat transfer devices.

Led by paleontologist Jason Bourke, a team of scientists at Ohio University used CT scans to document the anatomy of nasal passages in two different ankylosaur species. The team then modeled airflow through 3D reconstructions of these tubes. Bourke found that the convoluted passageways would have given the inhaled air more time and more surface area to warm up to body temperature by drawing heat away from nearby blood vessels. As a result, the blood would be cooled, and shunted to the brain to keep its temperature stable.

Modern mammals and birds use scroll-shaped bones called conchae or turbinates to warm inhaled air. But ankylosaurs seem to have accomplished the same result with a completely different anatomical construction.

“There are two ways that animal noses transfer heat while breathing,” says Bourke. “One is to pack a bunch of conchae into the air field, like most mammals and birds do–it’s spatially efficient. The other option is to do what lizards and crocodiles do and simply make the nasal airway much longer. Ankylosaurs took the second approach to the extreme.”

Lawrence Witmer, who was also involved with the study, said, “Our team discovered these ‘crazy-straw’ airways several years ago, but only recently have we been able to scientifically test hypotheses on how they functioned. By simulating airflow through these noses, we found that these stretched airways were effective heat exchangers. They would have allowed these multi-tonne beasts to keep their multi-ounce brains from overheating.”

Like our own noses, ankylosaur noses likely served more than one function. Even as it was conditioning the air it breathed, the convoluted passageways may have added resonance to the low-pitched sounds the animal uttered, allowing it to be heard over greater distances.

Note : The above story is based on materials provided by Society of Vertebrate Paleontology

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