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Imaggeo on Mondays: harnessing Earth’s inner heat

Imaggeo on Mondays: harnessing Earth’s inner heat

Iceland, the land of ice and fire, is well known for its volcanicity. Most famously, it is home to Eyjafjallajökull: the volcano which caused wide spread mayhem across European airspace when it erupted in 2010.

But not all the local volcanic activity is unwelcome. High temperature geothermal areas are a byproduct of the volcanic setting and the energy released can be used to power homes and infrastructure. Indeed, geothermal power facilities currently generate 25% of the country’s total electricity production.

“I took the photograph during a three hour walk in the Krafla area, a few kilometres away from Myvatn Lake in Northern Iceland,” explains Chiara Arrighi, a PhD student at the University of Florence in Italy, who took today’s featured image while on a two week holiday on the island.

There are 20 high-temperature areas containing steam fields with underground temperatures reaching 250°C within 1,000 m depth dotted across the country. Krafla, a caldera of about 10 km in diameter, and the wider Myvatn area is one of them. The volcano has a long history of eruptions, which drives the intrusion of magma at (geologically) shallow depths which in turn heats groundwater trapped deep underground, generating the steam field. Only a few hundred meters from the shooting location a power station of 60 MW capacity exploits high- and low-pressure steam from 18 boreholes.

Fumaroles and mud pots, like the one photographed by Chiara, are the surface expression of the geothermal activity. The discoloration of the rocks in the immediate vicinity of the bubbling mire is due to the acidic nature of the water in the pool. The steam is rich in hydrogen sulphide, which oxidises to sulphur and/or sulphuric acid as it mixes with oxygen when it reaches the surface. It deposits around the vents of fumaroles and as sulphuric acid in the stagnant waters, leading to alteration of the surrounding bedrock and soil.

If you pre-register for the 2017 General Assembly (Vienna, 22 – 28 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

Imaggeo on Mondays: Deep in the Himalayas

Deep in the Himalayas . Credit: Yuval Sadeh (distributed via imaggeo.egu.eu).

The Himalayas: vast, formidable and home to the Earth’s highest peaks. The mountain range stretches inexorably through Indian, Bhutan, Nepal, China (Tibet) and Pakistan separating the Tibetan Plateau to the north from India’s alluvial plains to the south.

India, as we know it today, started life much further south, as an island not far off the coast of Australia. It was separated from Asia (on the Eurasian plate) by the Tethys Ocean, a vast body of water which  wrapped, almost entirely, around the supercontinent Pangea. As the supercontinent started to break up, some 200 million years ago, India began its slow (in human terms, but quite fast geologically speaking) journey north towards Asia.

Moving at speeds between 9 to 16 cm per year (for comparison, human hair grows roughly 15 cm per year), by 80 million years ago, India was located 6,400 km south of Asia. The Tethys was being slowly subducted under the Asian plate and would eventually close (disappear) all together some 30 million years later, when the Indian plate collided against Asia and the Himalayas began to uplift.

The closing and subduction of the Tethyan Ocean, followed by the collision of the two continents produced the Himalayas. The mountain range is divided into six parallel belts, each of which has distinct lithotectonic zones. They are highly complex and represent a long history of tectonic processes and deformation events.

The high peaks of Nepal and China attract a fair share of the limelight, offering thrill seeking adventurers the possibility to get close to (if not scale) the highest mountains on Earth. But lesser known areas of the Himalayas also offer a window into the geological past of the planet and breathtaking scenes for intrepid people too.

Today’s photograph features a valley deep in the Indian Himalayas, and illustrates some geological, geomorphological and other phenomena’s together with a small village that was built inside this glacier curved valley.

 

If you pre-register for the 2017 General Assembly (Vienna, 22 – 28 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

January GeoRoundup: the best of the Earth sciences from across the web

January Georoundup: the best of the Earth sciences from across the web

The start of the new year sees the launch of a new series here on GeoLog. Drawing inspiration from popular stories on our social media channels, as well as unique and quirky research news, this monthly column aims to bring you the best of the Earth and planetary sciences from around the web.

Major stories

One of the biggest stories of this month was the anticipated release of the average global surface temperatures for 2016. It probably wasn’t a great surprise to discover that newly released National Oceanic and Atmospheric Administration (NOAA), NASA and the UK’s MetOffice data showed 2016 was the hottest year on record. On average, temperatures last year were 0.99℃ higher than the mid-century mean. It marks the third year in a row that Earth has registered record-breaking temperatures and highlights a trend, as climate blogger, Dana Nuccitelli, explains in an article for The Guardian:

“We’re now breaking global temperature records once every three years”

This video, showing NASA global surface temperature record since 1880, illustrates the point clearly. There were no record breaking years between 1945 and 1976, but since 1980 there have been 12.

 

This month also saw the inauguration of the 45th President of the United States. A fierce climate-change denier, Donald Trump’s rise to power has many worried about the future of climate change policy at the White House. To shine a light on the realities of climate change in the face of a largely climate sceptic administration and despite the ever rising global temperatures, The Guardian dedicate 24 hours to reporting on how climate changes is affecting regions across the globe. Among the comprehensive coverage this collection of climate facts stands out.

And it turns out the fears about the newly elected administration may not have been unfounded. Earlier this week the US Department of Agriculture and other federal agencies issued a ban preventing its scientists from communicating with the press and public about their research findings; even on social media. The order has since been rescinded, but US- based scientists remain concerned. In response, the AGU has written a letter to federal agencies in the US defending the protection of scientific integrity and open communications.

Closer to home, central Italy was struck by a sequence of four earthquakes on 18th of January, with the largest registering a magnitude of 5.7. The epicentres were located close to the town of Amatrice – in a region already shaken by several strong, and sometimes devastating, earthquakes in 2016. Later that day, and following a period of very heavy snowfall, a deadly avalanche in the Apennines buried a hotel in the Grand Sasso resort area, which had also been affected by the earthquakes. Although some news reports were quick to suggest the avalanche had been triggered by the earthquakes, researchers will need more data and a more detailed analysis to make this connection.

What you might have missed

While we are on the topic of climate change, a newly published report by the  European Environmental Agency is not to be missed.

“Climate change poses increasingly severe risks for ecosystems, human health and the economy in Europe.”

The document assesses the latest trends and projections on climate change and its impacts across Europe. While the effects of increasing temperatures will be felt across the continent, Southern and south-eastern Europe is projected to be a climate change hotspot with the forecasts showing the region will bear the brunt of the impacts.

A powerful 7.9 magnitude earthquake struck off the coast of Papua New Guinea on 22nd January. While the USGS estimated there was a low risk to property, tsunami warnings were issued across the South Pacific. In the wake of the tremor, the Incorporated Research Institutions for Seismology (IRIS) tweeted this neat ground motion visualisation of the earthquake waves.

A study published in Nature and summarised in Eos, highlights that while overt discrimination of women in the geosciences has not been as prevalent in recent years, many female scientists are still subject to subtle and unconscious bias leading to barriers to success in the geosciences.

Five links we liked

  • NOAA’s new GOES-R satellite for weather monitoring returned its first stunning photos of planet Earth – here are six reasons why the data it will acquire matter.
  • Snow fell in the Sahara for the first time in 37 years! This photogallery shows the usually red sand dunes of the desert covered in a sprinkling of white snow.
  • Scientist at The University of Cambridge have published the first global map of flow within the Earth’s mantle, showing that the surface moves up & down “like a yo-yo”.

The EGU story

At the EGU, the highlight of the month is the number of abstracts we received from researchers wishing to present and discuss their science at the EGU 2017 General Assembly. With over 17,500 abstracts, and an improved set-up to accommodate the high number of expected participants, the conference promises to be the largest and most exciting to date. We look forward to welcoming everyone in Vienna on 23–28 April!

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

Imaggeo on Mondays: the remotest place on Earth?

Imaggeo on Mondays: the remotest place on Earth?

Perhaps a bold claim, but at over 4,000 km away from Australia and 4,200 km from South Africa, Heard Island is unquestionably hard to reach.

The faraway and little know place is part of a group of volcanic islands known as HIMI (comprised of the Heard Island and McDonald Islands), located in the southwest Indian Ocean. Shrouded in persistent bad weather and surrounded by the vast ocean, Heard Island, the largest of the group, was first sighted by the merchant vessel Oriental in 1853.

Its late discovery and inaccessibility mean Heard Island is largely undisturbed by human activity (some research, surveillance, fishing and shipping take place on the island and it’s surrounding waters). It boasts a rich fauna and flora: seals, invertebrates, birds and seals call it home, as do hardy species of vegetation which grow low to the ground to avoid the fierce winds which batter the island.

Geologically speaking the islands are pretty unique too. They are the surface exposure of the second largest submarine plateau in the world, the Kerguelen Plateau. Limestones deposited some 45–50 million years ago began the process which saw the emergence of the islands from the ocean floor. Ancient volcanic activity followed, accumulating volcanic materials,  such as pillow lavas and volcanic sediments, up to 350m thick. For the last million years (or less) Heard Island has been dominated by volcanism, giving rise to the 2745m tall Big Ben and 700m tall Mt. Dixon. Eruptions and volcanic events have been observed on the island since 1947. Much of the recent volcanism in the region has centered around McDonald island, which has grown 40 km in area and 100 m in height since the 1980s.   

As the group of islands provides a remarkable setting, where geological processes and evolution (given that large populations of marine birds and mammals numbering in the millions, but low species diversity) can be observed in in real time, UNESCO declared HIMI a World Heritage Site back in 1997.

If you pre-register for the 2017 General Assembly (Vienna, 22 – 28 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

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