Ocean’s journey towards the center of the Earth

A Monash geoscientist and a team of international researchers have discovered the existence of an ocean floor was destroyed 50 to 20 million years ago, proving that New Caledonia and New Zealand are geographically connected.

Using new computer modelling programs Wouter Schellart and the team reconstructed the prehistoric cataclysm that took place when a tectonic plate between Australia and New Zealand was subducted 1100 kilometres into the Earth’s interior and at the same time formed a long chain of volcanic islands at the surface.

Mr Schellart conducted the research, published in the world-leading journal Earth and Planetary Science Letters, in collaboration with Brian Kennett from ANU (Canberra) and Wim Spakman and Maisha Amaru from Utrecht University in the Netherlands.

“Until now many geologists have only looked at New Caledonia and New Zealand separately and didn’t see a connection, Mr Schellart said.

“In our new reconstruction, which looked at a much larger region including eastern Australia, New Zealand, Fiji, Vanuatu, New Caledonia and New Guinea, we saw a large number of similarities between New Caledonia and northern New Zealand in terms of geology, structure, volcanism and timing of geological events.

“We then searched deep within the Earth for proof of a connection and found the evidence 1100 km below the Tasman Sea in the form of a subducted tectonic plate.

“We combined reconstructions of the tectonic plates that cover the Earth’s surface with seismic tomography, a technique that allows one to look deep into the Earth’s interior using seismic waves that travel through the Earth’s interior to map different regions.

“We are now able to say a tectonic plate about 70 km thick, some 2500 km long and 700 km wide was subducted into the Earth’s interior.

“The discovery means there was a geographical connection between New Caledonia and New Zealand between 50 and 20 million years ago by a long chain of volcanic islands. This could be important for the migration of certain plant and animal species at that time,” Mr Schellart said.

Mr Schellart said the new discovery diffuses the debate about whether the continents and micro-continents in the Southwest Pacific have been completely separated since 100 million years ago and helps to explain some of the mysteries surrounding evolution in the region.

“As geologists present more data, and computer modelling programs become more hi-tech, it is likely we will learn more about our Earth’s history and the processes of evolution.”

Earth’s crust melts easier than thought

Mt. Rushmore granite crystallized from magma that formed 1.7 billion years ago. -  Peter Nabelek, University of Missouri
Mt. Rushmore granite crystallized from magma that formed 1.7 billion years ago. – Peter Nabelek, University of Missouri

Earth’s crust melts easier than previously thought, scientists have discovered.

In a paper published in this week’s issue of the journal Nature, geologists report results of a study of how well rocks conduct heat at different temperatures. They found that as rocks get hotter in Earth’s crust, they become better insulators and poorer conductors.

The findings provide insights into how magmas are formed, the scientists say, and will lead to better models of continental collision and the formation of mountain belts.

“These results shed important light on a geologic question: how large bodies of granite magma can be formed in Earth’s crust,” said Sonia Esperanca, a program director in the National Science Foundation (NSF)’s Division of Earth Sciences, which funded the research.

“In the presence of external heat sources, rocks heat up more efficiently than previously thought,” said geologist Alan Whittington of the University of Missouri. “We applied our findings to computer models that predict what happens to rocks when they get buried and heat up in mountain belts, such as the Himalayas today or the Black Hills in South Dakota in the geologic past.

“We found that strain heating, caused by tectonic movements during mountain belt formation, easily triggers crustal melting.”

In the study, the researchers used a laser-based technique to determine how long it took heat to conduct through different rock samples. In all their samples, thermal diffusivity, or how well a material conducts heat, decreased rapidly with increasing temperatures.

The thermal diffusivity of hot rocks and magmas was half that of what had been previously assumed.

“Most crustal melting on Earth comes from intrusions of hot basaltic magma from the Earth’s mantle,” said Peter Nabelek, also a geologist at the University of Missouri. “The problem is that during continental collisions, we don’t see intrusions of basaltic magma into continental crust.”

These experiments suggest that because of low thermal diffusivity, strain heating is much faster and more efficient. Once rocks get heated, they stay hotter for much longer, Nabelek said.

The processes take millions of years to happen, and scientists can only simulate them on a computer. The new data will allow them to create computer models that more accurately represent processes that occur during continental collisions.

New Madrid fault system may be shutting down

This map shows areas damaged by the Dec. 16, 1811, magnitude 7.2 earthquake. That earthquake was the first of three major temblors along the New Madrid fault in 1811 and 1812. -  (Image courtesy of Seth Stein, based on results by Susan Hough)
This map shows areas damaged by the Dec. 16, 1811, magnitude 7.2 earthquake. That earthquake was the first of three major temblors along the New Madrid fault in 1811 and 1812. – (Image courtesy of Seth Stein, based on results by Susan Hough)

The New Madrid fault system does not behave as earthquake hazard models assume and may be in the process of shutting down, a new study shows.

A team from Purdue and Northwestern universities analyzed the fault motion for eight years using global positioning system measurements and found that it is much less than expected given the 500- to 1,000-year repeat cycle for major earthquakes on that fault. The last large earthquakes in the New Madrid seismic zone were magnitude 7-7.5 events in 1811 and 1812.

Estimating an accurate earthquake threat for the area, which includes parts of Illinois, Indiana, Tennessee, Arkansas and Kentucky, is crucial for the communities potentially affected, said Eric Calais, the Purdue researcher who led the study.

“Our findings suggest the steady-state model of quasi-cyclical earthquakes that works well for faults at the boundaries of tectonic plates, such as the San Andreas fault, does not apply to the New Madrid fault,” said Calais, who is a professor of earth and atmospheric sciences. “At plate boundaries, faults move at a rate that is consistent with the rate of earthquakes so that past events are a reliable guide to the future. In continents, this does not work. The past is not necessarily a key to the future, which makes estimating earthquake hazard particularly difficult.”

The team determined that the ground surrounding the fault system is moving at a rate of less than 0.2 millimeters per year and there is likely no motion. A paper detailing the work is published in the current issue of Science magazine.

Seth Stein, co-author of the paper, said this surface movement represents energy being stored that could be released as an earthquake.

“Building up energy for an earthquake is like saving money for a big purchase,” said Stein, the William Deering Professor of Earth and Planetary Sciences at Northwestern University. “You put money in over a long period of time and then spend it all at once and have to start saving again.”

With an earthquake, it is elastic deformation that must be built up. This can be measured using GPS through movements on the surface, he said.

“The slower the ground moves, the longer it takes until the next earthquake, and if it stops moving, the fault could be shutting down,” Stein said. “We can’t tell whether the recent cluster of big earthquakes in the New Madrid is coming to an end. But the longer the GPS data keep showing no motion, the more likely it seems.”

The U.S. Geological Survey-funded study used data recorded at nine GPS antennas mounted in the ground in the earthquake zone.

“GPS technology can measure movement to the thickness of a fishing line,” Stein said. “Use of GPS to study earthquakes shows the impact a new technology can have. It lets us see that the world is different than we thought it was.”

In the Midwest there are other faults that show no activity today but have evidence of earthquakes occurring within the past 10,000 to 1 million years, Calais said.

“If other faults in the central and eastern U.S. have been active recently, geologically speaking, they could potentially be activated again in the future,” he said. “We need to develop a new paradigm for how earthquakes happen at faults that are inside continents.”

Calais and Stein are exploring possible explanations for the behavior of faults like the New Madrid. One possibility is that earthquakes in these areas occur in clusters and then migrate to a nearby fault.

“There is the possibility that seismicity migrates with time as earthquakes trigger earthquakes on nearby faults,” Calais said. “Geologists studying the seismic history of faults have found that there have been earthquakes on several faults in the central and eastern U.S. and that they seem to produce bursts of earthquakes and then turn off.”

The team is doing additional analysis and modeling to study this further.

Fledgling mantle plume may be cause of African volcano’s unique lava

Nyiragongo, an active African volcano, possesses lava unlike any other in the world, which may point toward its source being a new mantle plume says a University of Rochester geochemist. The lava composition indicates that a mantle plume-an upwelling of intense heat from near the core of the Earth-may be bubbling to life beneath the soil of the Democratic Republic of the Congo. The findings are presented in the current issue of the journal Chemical Geology.

“This is the most fluid lava anyone has seen in the world,” says Asish Basu, professor of earth science at the University of Rochester. “It’s unlike anything coming out of any other volcano. We believe we’re seeing the beginning of a plume that is pushing up the entire area and contributing to volcanism and earthquakes.”

Basu analyzed the lava, which resides in the world’s largest lava lake-more than 600 feet wide inside the summit of Nyiragongo-and found that the isotopic compositions of neodymium and strontium are identical to ancient asteroids. This suggests, says Basu, that the lava is coming from a place deep inside the Earth where the source of molten rock is in its pristine condition.

Because the Earth’s crust is undergoing constant change via tectonic motion, weathering, and resurfacing, its chemical composition has been dramatically altered over its 4-billion-year lifespan, but the Nyiragongo magma source in the deep mantle has not, says Basu. That magma source is thought to retain some of the solar system’s original make-up of elements, and this is what Basu and his colleagues believe they have detected in Nyiragongo’s lava lak

Scientists believe mantle plumes can last hundreds of millions of years, and that their heat can create phenomena such as Yellowstone National Park or the string of Hawaiian Islands. Basu says Nyiragongo’s frequent eruptions may be the birthing pains of a similar plume and the possible beginning of new large-scale geological formations in the region.

Basu says other well known features of the region also point toward the idea of a growing plume. Nyiragongo lies on a vast ring of volcanoes and fissures that wrap around Uganda and the United Republic of Tanzania, and inside this ring the land is domed upward more than a mile above sea level. Basu believes the head of the plume is pooling in this region, pushing it upward like a 500-mile-wide air bubble in a pie crust.

But it is Nyiragongo, says Basu, that is being fed directly from the plume. Another volcano, Nyamuragira, just 15 miles to the north of Nyiragongo displays much more conventional lava compositions. Basu says this is because Nyamuragira is being fed from the edge of where the plume’s head is pooling, mixing in elements of melted crust and upper mantle, whereas Nyiragongo is being fed directly from the plume’s main body. Together the two mountains are responsible for approximately 40 percent of all of Africa’s volcanic eruptions.

“This is a very troubled region of the world, and we hope to be able to help better understand the conditions under which the people of that area must live,” says Basu. Nyiragongo last erupted in 2002, sending its super-fluid lava down its slopes at more than 60 miles per hour toward the nearby town of Goma, destroying 4,500 buildings and leaving 120,000 homeless. Basu and other scientists hope that understanding the composition of the lava that feeds Nyiragongo may help ongoing worldwide scientific efforts to understand the hazards of the region.

Leading geoscientists to discuss alternative energy, water, health and public policy issues

More than 300 geoscientists will gather soon for the 43rd Annual Meeting of the South-Central Section of the Geological Society of America. The meeting, which takes place at the UT Dallas Conference Center, is chaired by geoscientists from UT Dallas.

Eight themed sessions will highlight cutting-edge scientific research and feature technical presentations on geology and health issues, water resource challenges and shale reservoirs, as well as the geologic evolution of the US-Mexico border region, Texas-Oklahoma, Big Bend, and Permian Basin regions. More than 130 presentations will be made by academic and industry scientists, undergraduates and graduate students.

The meeting’s geology and health talks will cover contaminated groundwater, lead poisoning in children and the possible link between global warming and the northward expansion of the U.S. kidney stone “belt.”

Presentations on water resource challenges deal with stresses to local aquifer systems and freshwater in light of increased water demand and encroaching sea levels. Changes in local hydrogeologic environments over time will be covered.

Another popular theme session consists of several talks aimed at understanding the nature of local shale reservoirs and methods for extracting shale gas and shale oil in the Barnett Shale (Fort Worth area), Williston (Michigan area) and Appalachian basins (Eastern U.S.).

The sessions on Monday will close with a free and open public policy forum at 3:30 in the Conference Center led by UT Dallas President Dr. David E. Daniel. Panelists will discuss the role geoscientist can and should play in improving public policies concerning water, energy and land use.

To view the technical program, visit http://gsa.confex.com/gsa/2009SC/finalprogram/.

MEETING INFORMATION:



Complete meeting information is available at http://www.geosociety.org/sectdiv/southc/09mtg/index.htm

Information on registration is available at http://www.geosociety.org/sectdiv/southc/09mtg/registration.htm

MEDIA REGISTRATION INFORMATION



Eligibility for media registration is as follows:

  • Working press representing bona fide, recognized news media with a press card, letter or business card from the publication.

  • Freelance science writers, presenting a current membership card from NASW, ISWA, regional affiliates of NASW, ISWA, CSWA, ACS, ABSW, EUSJA, or evidence of work pertaining to science published in 2008 or 2009.

  • PIOs of scientific societies, educational institutions, and government agencies.

Journalists and PIOs must pay for any short courses or field trips in which they participate. Representatives of the business side of news media, publishing houses, and for-profit corporations must register at the main registration desk and pay the appropriate fees.

Complimentary meeting registration covers attendance at all technical sessions and access to the exhibit hall. Media must pay regular fees for paid luncheons, field trips, etc.

First English-language account of scientists’ quest to measure the globe

Full Meridian of Glory: Perilous Adventures in the Competition to Measure the Earth by Paul Murdin is an adventure story of the Paris Meridian and the scientists who worked through revolution, war, rebellion, piracy, fire, shipwreck, blockade, snow, tropical heat, kidnapping, murder and turbulent love affairs to pursue an intellectual problem of mapmaking and science.

Financed by the French government, the Paris Academy of Sciences was put to the task to measure France by defining the line later known as the Paris Meridian. From the seventeenth to nineteenth centuries, a multitude of astronomers and geodesists were employed to extend this work to measure the entire Earth. This book is about what they did and why.

Full Meridian of Glory is the first English-language account of this historical material in its entirety. It is the story of the scientists who created the Paris Meridian, and collaborated in alliances and split into warring factions. The book details the personal, national and political conflicts and disputes as they strived for ideals of accuracy, truth and objectivity.

Murdin vividly writes about the adventures of the scientists in France, Spain, Lapland and Ecuador who pursued their quest to measure the globe. They turned a practical problem into a crucial scientific test of one of the most important intellectual problems of their time – Newton’s theory of universal gravitation. Their work affected the course of science and politics, and left its mark on the landscape, the art and the literature of history and of our own age.

Paul Murdin is treasurer of the Royal Astronomical Society and Senior Fellow at Cambridge University.

Full Meridian of Glory is published by Springer, the second-largest publisher of journals in the science, technology, and medicine (STM) sector and the largest publisher of STM books. Springer is part of Springer Science+Business Media, one of the world’s leading suppliers of scientific and specialist literature.

Wenchuan earthquake mudslides emit greenhouse gas

Mudslides that followed the 12 May 2008 Wenchuan, China earthquake, ranked by the US Geological Survey as the 11th deadliest earthquake ever recorded, may cause a carbon-dioxide release in upcoming decades equivalent to two percent of current annual global carbon emissions from fossil fuel combustion, a new study shows.

Mudslides wipe away plants and topsoil, depleting terrain of nutrients for plant regrowth and burying swaths of vegetation. Buried vegetable matter decomposes and releases carbon dioxide and other gases to the atmosphere.

The expected carbon dioxide release from the mudslides following the Wenchuan earthquake is similar to that caused by Hurricane Katrina’s plant damage, report Diandong Ren, of the University of Texas at Austin, and his colleagues, who used a computer model to predict the ecosystem impacts of the mudslides.

What’s more, the vegetation destruction will lead to a loss of nitrogen from the quake-devastated region’s ecosystem twice as large as the loss of that nutrient from California ecosystems because of the October 2007 wildfires there, Ren says. And, as the biomass buried by the China quake rots, 14 percent of the nitrogen will be spewed into the atmosphere as nitrous oxide, a pollutant typically released from agricultural operations, automobiles, and other sources.

The team will publish its findings on 4 March 2009 in Geophysical Research Letters, a journal of the American Geophysical Union (AGU).

Although landscapes devastated by the Chinese earthquake may re-green soon, the recovery will be cosmetic, says Ren. “From above, the area will look green in a few years, because grass grows back quickly, but the soil nutrients recover very slowly, and other kinds of plants won’t grow,” he says.

The magnitude-7.9 Wenchuan quake was followed by many aftershocks in the Sichuan Basin, an area that, because of its geological features – deep valleys enclosed by high mountains with steep slopes – is already prone to landslides. May is also the rainy season in Sichuan, and the combination of aftershocks and major precipitation events in the days following the earthquake caused severe mudslides. The avalanches killed thousands, destroyed roads and blocked rivers and access to relief, and shredded water and power stations, among other facilities. To predict ecosystem impacts of the mudslides, Ren and his collaborators applied a comprehensive computer model of landslides that incorporates several physical parameters, such as soil mechanics, root mechanical reinforcement (the root’s grip of the dirt, which mitigates erosion), and precipitation.

Ren’s model also shows that the primary mudslides following the earthquake removed large areas of nutrient-rich topsoil, leaving behind deep scars in the land that will take decades to recover, preventing the re-growth of vegetation.

The researchers write in their paper that, although being able to predict the location and timing of a mudslide is essential to mitigate its impacts, current mudslide models are not accurate enough.

“Previous approaches, which are mainly based on statistical approaches and empirical measures, have no predictive ability of where mudslides are going to happen,” Ren says. His model, he claims, could be applied to forecast under what circumstances a landslide would occur at a specific location. He points out this would be particularly useful for places such as Southern California, where global warming predictions call for an increase in the frequency of these events.

US-led international research team confirms Alps-like mountain range exists

Flying twin-engine light aircraft the equivalent of several trips around the globe and establishing a network of seismic instruments across an area the size of Texas, a U.S.-led, international team of scientists has not only verified the existence of a mountain range that is suspected to have caused the massive East Antarctic Ice Sheet to form, but also has created a detailed picture of the rugged landscape buried under more than four kilometers (2.5 miles) of ice.

“Working cooperatively in some of the harshest conditions imaginable, all the while working in temperatures that averaged -30 degrees Celsius, our seven-nation team has produced detailed images of last unexplored mountain range on Earth,” said Michael Studinger, of Columbia University’s Lamont-Doherty Earth Observatory, the co-leader of the U.S. portion of the Antarctica’s Gamburstev Province (AGAP) project. “As our two survey aircraft flew over the flat white ice sheet, the instrumentation revealed a remarkably rugged terrain with deeply etched valleys and very steep mountain peaks.”

The National Science Foundation (NSF), in its role as manager of the U.S. Antarctic Program, provided much of the complex logistical support that made the discoveries possible. NSF also supported U.S. researchers from Columbia University, Washington University in St. Louis, Pennsylvania State University, the Center for Remote Sensing of Ice Sheets (CReSIS) at the University of Kansas, the U.S. Geological Survey (USGS) and the Incorporated Research Institutions in Seismology (IRIS).

The initial AGAP findings–which are based on both the aerogeophysical surveys and on data from a network of seismic sensors deployed as part of the project–while extremely exciting, also raise additional questions about the role of the Gamburtsevs in birthing the East Antarctic Ice Sheet, which extends over more than 10 million square kilometers atop the bedrock of Antarctica, said geophysicist Fausto Ferraccioli, of the British Antarctic Survey (BAS), who led the U.K. science team.

“We now know that not only are the mountains the size of the European Alps but they also have similar peaks and valleys,” he said. “But this adds even more mystery about how the vast East Antarctic Ice Sheet formed.”

He added that “if the ice sheet grew slowly then we would expect to see the mountains eroded into a plateau shape. But the presence of peaks and valleys could suggest that the ice sheet formed quickly–we just don’t know. Our big challenge now is to dive into the data to get a better understanding of what happened” millions of years ago.

The AGAP survey area covered roughly 2 million square kilometers of the ice sheet.

The initial data also appear to confirm earlier findings that a vast aquatic system of lakes and rivers exists beneath the ice sheet of Antarctica, a continent that is the size of the U.S. and Mexico combined.

“The temperatures at our camps hovered around -30 degrees Celsius, but three kilometers beneath us at the bottom of the ice sheet we saw liquid water in the valleys,” said AGAP U.S. Co-leader Robin Bell, also of Lamont Doherty. “The radar mounted on the wings of the aircraft transmitted energy through the thick ice and let us know that it was much warmer at the base of the ice sheet.”

The AGAP data will help scientists to determine the origin of the East Antarctic Ice Sheet and the Gamburtsevs’ role in it. It will also help them to understand the role the subglacial aquatic system plays in the dynamics of ice sheets, which will, in turn, help reduce scientific uncertainties in predictions of potential future sea level rise. The most recent report of the Intergovernmental Panel on Climate Change (IPCC) said that it is difficult to predict how much the vast ice sheets of Greenland and Antarctica will contribute to sea-level rise because so little is known about the behavior of the ice sheets.

The data also will be used to help locate where the world’s oldest ice is located.

The AGAP discoveries were made through fieldwork that took place in December and January, near the official conclusion of the International Polar Year (IPY), the largest coordinated international scientific effort in five decades. Ceremonies marking the conclusion of IPY fieldwork will take place in Geneva, Switzerland on Feb. 25.

NSF is the lead U.S. agency for IPY. Through the Antarctic Program, NSF manages all federally funded research on the southernmost continent.

Fully in the spirit of IPY, noted Detlef Damaske of Germany’s Federal Institute for Geosciences and Natural Resources, teams of scientists, engineers, pilots and support staff from Australia, Canada, China, Germany, Japan, the U.K. and the U.S. pooled their knowledge, expertise and logistical resources to deploy two survey aircraft, equipped with ice-penetrating radar, gravimeters and magnetic sensors as well as the network of seismometers, an effort that no one nation alone could have mounted.

“This is a fantastic finale to IPY,” added Ferraccioli.

Bell meanwhile, noted that AGAP is “emblematic of what the international science community can accomplish when working together.”

In one of the most ambitious, challenging and adventurous ‘deep field’ Antarctic IPY expeditions, AGAP scientists gathered the terabytes of data needed to create images of the enigmatic Gamburtsevs, first discovered by Russian scientists in 1957 during the International Geophysical Year (IGY), the predecessor to IPY.

While the planes made a series of survey flights, covering a total of 120,000 square kilometers, the seismologists flew to 26 different sites throughout an area larger than the state of Texas using Twin Otter aircraft equipped with skis, to install scientific equipment that will run for the next year on solar power and batteries.

The seismology team, from Washington University, Penn State, IRIS, and Japan’s National Institute of Polar Research, also recovered ten seismographs that have been collecting data since last year over the dark Antarctic winter at temperatures as low as -73 degrees Celsius (-100 degrees Fahrenheit).

“The season was a great success,” said Douglas Wiens, of Washington University in St. Louis. “We recovered the first seismic recordings from this entire part of Antarctica, and operated seismographs over the Antarctic winter at temperatures as low as -100 F for the first time. Now, we are poring over the data to find out what is responsible for pushing up mountains in this part of Antarctica.”

Oceanic seesaw links Northern and Southern hemisphere during abrupt climate change

Very large and abrupt changes in temperature recorded over Greenland and across the North Atlantic during the last Ice Age were actually global in extent, according to an international team of researchers led by Cardiff University.

New research, published in the journal Nature today, supports the idea that changes in ocean circulation within the Atlantic played a central role in abrupt climate change on a global scale.

Using a sediment core taken from the seafloor in the South Atlantic, the team were able to create a detailed reconstruction of ocean conditions in the South Atlantic during the final phases of the last ice age.

Dr Stephen Barker, Cardiff University’s School of Earth and Ocean Sciences and lead author on the paper, said: “During this period very large and abrupt changes in temperature were observed across the North Atlantic region. However, evidence for the direct transmission of these shifts between the northern and southern hemispheres has so far been lacking”.

The new study suggests that abrupt changes in the north were accompanied by equally abrupt but opposite changes in the south. It provides the first concrete evidence of an immediate seesaw connection between the North and South Atlantic. The data shows, for example, that an abrupt cooling in the north would be accompanied by a rapid southerly shift of ocean fronts in the Southern Ocean, followed by more gradual warming across the south.

Dr Barker explains: “The most intuitive way to explain these changes is by varying the strength of ocean circulation in the Atlantic. By weakening the circulation, the heat transported northwards would be retained in the south.”

Climate physicist, Dr Gregor Knorr, co-author of the study and now based at the Alfred Wegener Institute in Germany, said: “Our new results agree with climate models that predict a rapid transmission of climate signals between the two hemispheres as a consequence of abrupt changes in ocean circulation.”

The study has wide implications for our understanding of abrupt climate change. Dr Ian Hall, School of Earth and Ocean Sciences, said: “While it is unlikely that an abrupt change in climate, related to changes in ocean circulation, will occur in the near future, our results suggest that if such an extreme scenario did occur, its effects could be felt globally within years to decades.”

Intelligent use of the Earth’s heat

Geothermal energy is increasingly contributing to the power supply world wide. Iceland is world-leader in expanding development of geothermal utilization: in recent years the annual power supply here doubled to more than 500 MW alone in the supply of electricity. And also in Germany, a dynamic development is to be seen: over 100 MW of heat are currently being provided through geothermal energy.

Alone in the region of Travale, in the pioneering country Italy, a team of european scientists have localizied geothermal reservoirs, holding a potential comparable to the effectiveness of 1.000 wind power plants. This is one of the results presented at the international final conference of the project ?I-GET” (Integrated Geophysical Exploration Technologies for deep fractured geothermal systems) in Potsdam. The aim of this European Union project, in which seven european nations participated, was the development of cutting-edge geophysical methods with which potential geothermal reservoirs can be safely explored and directly tapped.

?The new methods deliver important decision-support for the selection of sites for future geothermal projects. With this we can considerably reduce the risk of expensive misdrills” explains Dr. Ernst Huenges, Head of Geothermal Research at the host institute GFZ – German Research Centre for Geosciences.

The newly developed approaches have been tested at four European geothermal locations with different geological and thermo¬dynamic conditions: high-temperature reservoirs have been examined in Travale/Italien (metamorphic rocks) and in Hengill/Island (volcanic rocks), two deposits with medium-temperature in deep sediment rocks are Groß-Schönebeck/Germany and Skierniewice/Poland. The methodology is based on the measurement of seismic velocities and electrical conductivity in the underground which deliver information on the rock-physical characteristics at depth. Different methods have, hereby, been combined, in addition to borehole measurements and rock-analysis

I-GET experiments have been carried out using a case study in the surrounding of the GFZ research borehole at Groß Schönebeck, nordwest of Berlin. And here, extensive pre-knowledge from experimental investigations in the in situ geothermal-laboratory in Groß Schönebeck is already available. The geological conditions prevailing in the North German Basin are representative for further parts of central Europe, and thus the research results are also of high interest beyond Germany’s borders.

The GFZ, member of the Helmholtz-Association of German Research Centres, had the leading role in I-GET and was able to contribute with is acquired knowledge in the field of low-temperature geothermal reservoirs.

The results of I-GET emanate worldwide: experts from Indonesia, New Zealand, Australia, Japan and the USA were among the 120 scientists and industry representatives from the 20 countries who participated at the meeting.

?Reliable geothermal technologies are in demand worldwide. Even countries with a long experience in geothermal energy such as Indonesia and New Zealand are interested in the results acquired in I-GET”, says Dr. Ernst Huenges. Therefore, the GFZ is further developing its geothermal research and is currently setting up an International Centre for Geothermal Research, which will, in particular, carry out application-oriented large-scale projects on a national and international level.