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Imaggeo on Mondays: Cordillera del Paine

9 Jul

Cordillera del Paine by Martin Mergili, distributed by EGU under a Creative Commons licence.

Images such as the one above inspire scientists and nature lovers alike. This photograph, showing a Chilean landscape with elements representative of various Earth-science disciplines, is simply stunning. In a beautiful mix of shapes and colours, a quiet lake with floating icebergs appears tucked in between a roughed mountain in the background and a colourful double rainbow in the foreground.

The photographer, Martin Mergili of the University of Natural Resources and Life Sciences in Vienna, captured this inspiring scenery during a holiday trip a few years ago. The photo shows the eastern edge of the southern part of Cordillera del Paine, a “small but spectacular” mountain group in the Torres del Paine National Park, which is located in Chilean Patagonia almost 2,000 kilometres south of Santiago de Chile.

“The prominent peaks visible in the left portion of the image are the Cuernos del Paine,” Martin explains. “The rainbow in the foreground is not just decoration, it reflects the ever-changing weather patterns characteristic of that area. Even though it is located in the rainshade of the Cordillera at the edge of the semi-arid Patagonian lowlands, the westerlies bring a lot of moist air from the Pacific Ocean. The icebergs in the lake in the foreground (Lago Grey) originate from the large Glaciar Grey calving into the lake.”

More stunning images of this and other landscapes are available from Martin’s website.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

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Imaggeo on Mondays: Jointed Colorado Rockies

18 Jun

Jointed Colorado Rockies by Will Gosnold, distributed by the EGU under a Creative Commons license

The Rocky Mountains, or Rockies, are a North American mountain system stretching around 5,000 km from northern British Columbia, Canada, to New Mexico in the southwestern United States. They are made up of a discontinuous series of mountain ranges with distinct geological origins, the last of which was formed during the Laramide orogeny (mountain formation event) 80–55 million years ago.

With a population of 568,158 (2011 estimate), Wyoming has the lowest population and second lowest population density of any US state, yet it has the 10th largest area. Its environment is defined by its geological history, lying at the intersection of the Rockies to the west and, to the east, the Great Plains, a broad expanse of flat land running north to south across North America.

The sheer size and distance covered by the Rockies, even through just the one state of Wyoming, is hard to imagine by European standards. At 253,348 sq km, Wyoming itself has a greater area, for example, than the UK, Romania, Belarus, Greece, or Bulgaria, just to name a few. Perhaps the best way to understand the scale of the Rockies is by experiencing them from above, an experience captured here by Will Gosnold through an aircraft window. Gosnold, a professor within the Department of Geology and Geological Engineering at the University of North Dakota, describes this photo opportunity, “I took the photo from the window of a Delta Airlines plane, over what is likely Wyoming, during a flight from San Francisco to Minneapolis while returning from the Fall Meeting of the American Geophysical Union on 9 December 2011.”

Apart from boasting the Rockies and its vast expanse of publicly owned land, including a section of Yellowstone National Park, Wyoming produces a broad array of mineral commodities. Apart from being the largest and second largest producer of coal and natural gas respectively in the US, it also produces coalbed methane, crude oil, uranium, and trona, an evaporite mineral used for the production of washing soda (sodium carbonate). Diamond and uranium mines have also recently operated in the state.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Imaggeo on Mondays: Apostles along the Great Ocean Road

4 Jun

The 12 Apostles along the Great Ocean Road by Fabien Darrouzet, distributed by EGU under a Creative Commons licence.

Tucked between the rough Southern Ocean and stunning cliff tops, Australia’s Great Ocean Road is one of the world’s most scenic routes. The 243-kilometre stretch of road along the country’s south-eastern coastline is surrounded by beautiful beaches, lush rainforests, as well as incredible geological formations. The 12 Apostles, stacks of rocks located in the Port Campbell National Park, are one of the highlights of the route.

Two of these structures are visible in this wild scene captured by Fabien Darrouzet of the Belgian Institute for Space Aeronomy in Brussels. He took this picture in June 2011 while travelling in Australia before the XXV General Assembly of the International Union of Geodesy and Geophysics in Melbourne.

“Those stacks are composed by miocene limestone rock, and were formed by erosion,” Fabien explains. “The Southern Ocean gradually eroded the soft limestone of the coast to form caves in the cliffs, which then became arches, which in turn collapsed, leaving rock stacks up to 45 metres high.”

The wild Southern Ocean with its rough waves is still shaping these rock formations. “Due to the strong waves in this area, those stacks are susceptible to more erosion, and can even collapse, as one did in July 2005,” Fabien says. “This means these geoscience elements are in constant evolution, and they show the changes of nature due to nature itself.”

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Publications by the EGU

10 May

The EGU is responsible for 14 Open Access journals, all freely available online

Since 2001, the EGU and Open Access publishing house Copernicus Publications has published a growing number of successful geoscientific journals. These include 14 peer-reviewed Open Access journals, of which 11 have a Thomson Reuters Impact Factor, placing them in the top echelon of their respective discipline. EGU also publishes a host of other materials available in paper and online. As a signatory of the Berlin Open Access Declaration (2003), the EGU is committed to making all their publications freely available.

The EGU’s Open Access scientific journals are:


Imaggeo on Mondays: A rock and a hard place

23 Apr

'My way' by Amirhossein Mojtahedzadeh, distributed by EGU under a Creative Commons license

Rocks within the Earth are constantly being subjected to forces that bend, twist, and fracture them, causing them to change shape and size. This process is known as deformation. Polyphase deformation occurs over time when rocks are affected, or stressed, by more than one phase of deformation.

Geomorphologist Amirhossein Mojtahedzadeh captured this stunning scene whilst on field work. “This photo was taken near Qom in central Iran. These formations are contained by sedimentary rocks, which underwent polyphase deformation and metamorphism – clearly visible in areas at this location,” he says.

Iran covers an area of 1 648 000 square kilometres. The central plateau, located between the bounding mountain ranges, is a major feature of the country’s diverse morphology.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Imaggeo on Mondays: A mineral under the microscope

9 Apr

Epidote by Gunnar Ries, distributed by EGU under a Creative Commons license

Epidote, an abundant rock-forming mineral found in metamorphic rocks, nearly always appears in green, although it may vary in shade and tone. Under a microscope of polarized light, however, it exhibits strong pleochroism, that is, it shows different colors when observed at different angles. The thin section (a laboratory preparation of a mineral or rock sample for use with a polarizing microscope) in the picture displays strong yellow colours, beautiful tones of pink and purple, and light and dark shades of blue.

This photography under a microscope was taken by mineralogist Gunnar Ries. He comments, “I took this picture in 1996 from a unakite sampled in the German state of Mecklenburg-Vorpommern, near the town of Rerik, during a field trip. The thin section was one of the first I ever made!”

Although Epidote can be found worldwide, including in Pakistan, China, and across Africa, it is particularly prevalent in the Austrian Alps, where it appears in the form of distinctly large, sharp, and lustrous crystals. Epitode is often seen on display at mineral conventions, with the finest pieces – featuring delicate and elongated crystals – being highly treasured by collectors.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Imaggeo on Mondays: Reflecting mountains in Sørfjorden, Norway

12 Mar

A sunny morning in Sørfjorden by Martin Mergili, distributed by EGU under a Creative Commons licence.

Located just southeast of Bergen on the Norwegian Atlantic coast, Hardangerfjorden is the third longest fjord in the world, measuring more than 170 km from the Atlantic Ocean to the Hardangervidda mountain plateau. Its longest branch, Sørfjorden, cuts 50 km from the main fjord and ends at Odda.

Geormorphologist Martin Mergili visited the area in 2008, following the 33rd International Geological Congress in Oslo. “The photo was taken from the small town of Odda at the southernmost tip of the Sørfjord, a southern branch of the Hardangerfjord. The western slopes of the deeply incised fjord, which are shown on the photograph, lead up to the Folgefonna, one of the major ice fields of Norway. Partly glacierised highlands and deeply incised fjords are characteristic landforms of western Norway, formed during the Pleistocene. The picture was shot on a sunny and calm morning,” he recollects.

Fjords are formed by abrasion, when a retreating glacier cuts a U-shaped valley into the surrounding bedrock. They are primarily located in mountainous regions, against prevailing westerly marine winds that are orthogonally lifted over the mountains resulting in abundant snowfall to feed the glaciers. Coasts featuring the most pronounced fjords can be found in western Norway, northwestern North America, and southwestern New Zealand.

To view more from Martin Mergili’s collection of photos, many of which have geoscientific relevance, please visit: www.mergili.at/worldimages.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Imaggeo on Mondays: Open pit in Mirny, Siberia

5 Mar

Mirny open pit mine by Jean-Daniel Paris, distributed by EGU under a Creative Commons licence.

This former open-pit diamond mine is currently the second largest excavated hole in the world. After diamond was discovered in there in 1955, the area became the first and largest diamond mine in the Soviet Union, producing up to 2,000 kg of diamond per year during the 1960s. Its surface operations continued until 2001 and the mine was permanently shut in 2011.

This photo was taken on 22 July 2008 by climatologist Jean-Daniel Paris on a trip with the YAK-AEROSIB project (https://yak-aerosib.lsce.ipsl.fr), which sought to measure the trophospheric composition of greenhouse gases and pollutants over Siberia.

“The scientific flight itinerary from Novosibirsk to Yakutsk and back is completed in about five days. Along the way, we overnighted at a handful of towns, including Mirny. We spent a few hours around the town waiting for the refueling and visited this old diamond mine pit. Despite emissions from its scattered industrial and extraction activities, Siberia remains close enough to a pristine continental tropospheric laboratory,” commented Paris.

Diamond is formed when carbon bearing material is exposed to high pressure within the Earth’s lithospheric mantle or at the site of a meteor strike. Annually, approximately 26,000 kg of natural diamond is mined worldwide, a harvest worth almost €7 billion. Roughly half the planet’s mines are located in Central and Southern Africa, but others can be found in Canada, Brazil, Australia, India, and Russia. Another 100,000 kg is also produced synthetically each year and is mainly used for industrial purposes.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Imaggeo on Mondays: Huts in Arcachon Bay

16 Jan

The Tchanquees Huts in the Arcachon Bay by Yann Vitasse, distributed by EGU under a Creative Commons licence.

Yann Vitasse, now a researcher at the Institute of Botany, University of Basel in Switzerland, got a wonderful present in 2009 for completing his PhD: a flight on an ultralight aircraft above the southwest coast of France. It was then he took this stunning photo of the Arcachon Bay, a water area near Bordeaux that is fed by the Atlantic Ocean and by a number of fresh waterways.

“Here you see the famous Tchanquees Huts which were built on stilts in the middle of the Arcachon Bay, on the bird island. These huts were originally used for monitoring oyster beds,” Vitasse said.

The photo was taken at low tide, a time when the water covers an area of only 40 square kilometres. By comparison the bay takes up some 150 square kilometers at high tide, when the entire area to the left of the huts is covered by sea water.

The bird island, starting to the right of the huts, also varies in area being some 10 times larger at low tide. Geologists are still out on the origin of this structure. Some defend it is a former sandbar while others prefer the theory that it formed from the remains of a high dune shaped by the wind and the ocean.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

Sand Dunes at EGU GA 2012

22 Nov

Several participants in the Geoblogsphere having been posting recently about sand dunes. Its part of Sand Dune Week declared on twitter by Brian Romans. Some of the posts are listed by Matthew Francis or find more by searching on twitter for “sand dune week”.

There are three sessions at the European Geosciences Union General Assembly 2012 directly related to sand dunes, these are listed below. To submit an abstract visit the meeting website.

GM5.1 Aeolian Processes and Landforms

Convener: J.M. Nield, Co-Convener: J. King
Aeolian geomorphology covers a wide spectrum of research from the small scale study of processes in the field or laboratory to modelling projects predicting long-term dune field evolution. This session aims to bring together a diverse group of researchers that study wind-blown sediment (both sand and dust) and associated bedforms in a range of environments, from coastal and semi-arid regions, to hyper arid deserts. Contributions that use novel instrumentation in field studies, remote sensing at the landscape scale or innovative numerical modelling methods, are encouraged, particularly those which attempt to elucidate feedback between surface properties and sediment transport.

GM10.1/PS2.9 Planetary Geomorphology

Convener: S. Conway, Co-Conveners: M. Balme , C. Gallagher
This session aims to give a different perspective on planetary science by bringing together geomorphologists from terrestrial sciences with those who spend more time on other planets. Studies of landscapes on any scale on any solid body are welcome. We particularly encourage those who use Earth analogues (either in the field or laboratory) to present their work. Submissions can include studies on glacial, periglacial, aeolian, volcanic or fluvial landforms. We welcome submissions from geomorphologists who are new to planetary science.

AS4.13/CL4.7 Aeolian dust, initiator, player, and recorder of environmental change

Convener: P. Knippertz, Co-Convener: J.-B. Stuut

The interactions between aerosols, climate, and weather are among the large uncertainties of current climate and atmospheric research. Mineral dust is an important natural source of aerosol with significant implications on radiation, cloud microphysics, atmospheric chemistry and the carbon cycle via the fertilization of marine and terrestrial ecosystems.
In addition, properties of dust deposited in sediments and ice cores are important (paleo-)climate indicators.

This interdivision session is open to contributions dealing with:
(1) measurements of all aspects of the dust cycle (emission, transport, deposition, size distribution, particle characteristics) with in situ and remote sensing techniques,
(2) numerical simulations of dust on global and regional scales,
(3) meteorological conditions for dust storms, dust transport and deposition,
(4) interactions of dust with clouds and radiation,
(5) influence of dust on atmospheric chemistry,
(6) fertilization of ecosystems through dust deposition,
(7) any study using dust as a (paleo-)climate indicator including investigations of Loess, ice cores, lake sediments, ocean sediments and dunes.

We especially encourage our colleagues to submit papers on the integration of different disciplines and/or modeling of past, present and future climates.

Image by Ioannis Daglis, distributed by EGU under a Creative Commons licence.