KRAFLA MAGMA TEST BED (KMT) Logo here? Crossing the Scientific and. Technological Frontier. from Solid Rock to Magma

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1 KRAFLA MAGMA TEST BED (KMT) ersity of Liv Lavallee, Univ Krafla fumarole. Yan Logo here? erpool. Crossing the Scientific and Technological Frontier from Solid Rock to Magma

2 Introduction One of the great challenges in understanding Earth s crustal processes is the interface between the aqueous fluid-bearing or hydrothermal regime and the silicate melt-bearing or magmatic regime. The migrations of magma and fluid are the agents of mass and heat transfer within the crust and to the surface. Humans experience this as volcanic eruptions, geothermal energy, and ore deposits. The rate of heat loss from magma through a surrounding hydrothermal system controls the lifetime of the magma body and the energy available for extraction from the hydrothermal system. We can imagine a magma body as a thermos flask where the wall is the crystallized magma itself. This insulating wall is the critical interface of transition from magmatic to hydrothermal systems, but at very high temperatures its rock wall can deform so any fractures will quickly heal. Without melt or fluid to flow, heat transfer would be by conduction, which is mostly dependent on thickness of the wall. The high temperature face of this zone is hypothesized to be crystallizing magma and the low temperature face is thought to contain growing fluid-filled cracks. The answer to how magma and hydrothermal systems are coupled lies in this zone. Geothermal drilling in the Krafla Caldera, Iceland, serendipitously hit rhyolite magma at a depth of only 2

3 2100 m. This was a major breakthrough and provides unprecedented opportunities allowing us to: closely observe, sample, and manipulate the transition zone in order to rigorously test concepts of volcanic systems develop improved or new monitoring techniques for volcanology push drilling and sensor technology to the crust s high-temperature maximum explore the roots of geothermal systems and the potential for direct energy extraction from magma the ultimate geothermal resource. The concept of crossing a frontier is apt, because exploration of the interior of our planet has received less attention than exploration of outer space or the atom. With our burgeoning population, we need to pay more attention to the frontiers beneath us. This attention requires multinational and multistakeholder partnerships such as the Ocean Drilling Program and now the International Continental Scientific Drilling Program (ICDP), of which KMT is a part. The frontier between solid and molten Earth is one through which all of the Earth s crust has passed, but our observations have not. What is proposed is more than a drilling project. It is a cluster of coordinated, multidisciplinary efforts encompassing: borehole and sample observations coupled with large-scale experimental studies linked surface geophysical and geochemical observations advanced geothermal energy technology sensor development for extreme environments advanced volcanic eruption forecasting. It combines the serendipity of the Krafla discovery with the growing pressure temperature overlap of drilling, volcanology, and laboratory experimentation. This is the Krafla Magma Testbed (KMT). 3

4 Volcano monitoring Globally, governments spend large sums on volcano monitoring because with proper monitoring, the risk of disaster can be reduced. Volcanoes give early warning of eruption by: increases in small earthquakes inflation of the volcano on a scale of centimeters (or meters in extreme cases) changes in the amounts and chemistry of escaping gases. Such signs are readily detected by instrument networks at the surface and are termed unrest. The World Organization of Volcano Observatories (WOVO) has 79 members from 33 countries. National expenditures for observatories range from tens of millions Euros per year for prosperous countries with high vulnerabilities to modest operations that 4 are part of weather stations in other cases. Average fatalities per year are under one thousand, modest by comparison with floods and earthquakes, but volcanic catastrophes with hundreds of thousands killed and economic losses in the hundreds of billions are possible. Eruptions on this huge scale are geologically common but have not occurred in modern times. Today, most volcanoes that threaten significant populations or air routes are monitored with arrays of telemetered instruments to detect and measure unrest. However, the signals measured are only proxies for what the magma beneath the volcano is doing. This has never been directly observed, so we are in a worrying situation where decisions of great consequence are based on models that are untested.

5 By drilling through the rock magma interface and into magma, we can: establish where and under what conditions magma is stored beneath a volcano stimulate its boundary region by fluid injection to see whether the result is indeed the inferred unrest and ultimately place sensors near and even in magma to provide direct measurement of a rise in temperature or increase in pressure that could lead to eruption. if the magma is closer to the surface the a shorter warning time for its arrival at the surface. The fact that magma under Krafla was discovered at half the predicted depth is therefore reason enough to seriously re-evaluate existing volcano monitoring methods. The KMT will develop a World Volcano Model, a world standard for hazard assessment, monitoring, and data interpretation, comparable to that being developed for earthquakes. The latter development could be a complete gamechanger in monitoring strategy, providing greater assurance of timely and accurate warning, and perhaps shifting to more efficient, less labour-intensive monitoring strategies. A simple and certain result will be the ground-truthing of geophysical techniques such as seismic, electromagnetic, gravity, and geodetic measurements that are used to infer the presence of magma and transient changes in magma pressure. The threat of eruption is deemed to be higher 5

6 Geothermal potential 6

7 In many ways, geothermal energy is an ideal energy source for the future because it is: renewable (unlike fossil fuels) low to net zero in CO2 emission continuous independent of diurnal and seasonal cycles (unlike solar, wind, and hydroelectric) small in footprint and ecological impact because the production facility is sited on the fuel source free from the accident and spill hazards of transporting fossil fuels and nuclear waste, and from the major ecological impact of hydropower reservoirs. Despite its many advantages, geothermal energy currently makes up only about 0.1% of global power production. Geothermal power plants are relatively inefficient in converting heat to electricity compared to fossil fuel and nuclear plants, because they use lower temperature natural steam. They lack economies of scale because conventional practice yields only tens or hundreds of MWe production per geothermal field. Also, the resource is restricted geographically and not transportable, except by transmission of the electric power produced. KMT will test the feasibility of extracting heat directly from magma rather than indirectly from rocks heated by magma. This will increase the heat energy extractable from a geothermal field by an order of magnitude and the efficiency of conversion to electricity by a factor of two or three. Meanwhile, instead of transporting fuel to conveniently located power plants, the electricity can be transmitted to users by lowloss, high-voltage DC cables, including submarine cables. The demand for development and production of high-voltage DC transmission systems is currently driven by ocean wind-power farms, but high-grade geothermal fields can quickly benefit as well. As the drive to reduce anthropogenic CO2 emission increases, the development of geothermal energy must also increase. The use of supercritical steam heated directly by magma will dramatically change the economics of geothermal energy. Volcanic ranges and islands could become national and international power factories. In addition, the reduction of eruption risk is a possible collateral benefit. 7

8 Magma manipulation Now is the time to seize upon the convergence of multiple fields of science and engineering with a magma testbed. Geothermal drilling and flow testing, which by nature perturb the system and measure the response, have reached the magmatic hearth. Real-time volcano monitoring techniques have been revolutionized through conversion from analog to digital systems and the advent of geographical positioning systems (GPS) and interferometric synthetic aperture radar (ISAR) technology. This has in turn led to a blossoming of models for magma that must be tested to be reliably used. Large-scale laboratory experiments with rock under magmatic conditions and sophisticated finite-element fluid-dynamic models can now inform us of both natural and drilling induced perturbations to the magmatic system. In turn, new observations through drilling can inform new laboratory experiments. Sensors that are being developed to monitor conditions within jet and rocket engines, which have the same temperature regime as magma, can be applied to direct monitoring. The result of the KMT will be that for the first time we will have: a real understanding of time-dependent behavior of magmatic systems in response to pressure and temperature changes and fluid injection magma engineering that could be used to greatly increase the extraction of geothermal energy the possibility of reducing the volume of shallow eruptible magma in the system, thereby reducing eruption risk. 8

9 Technology transfer from the Kafla Magma testbed We will be working at the limits of technology in drilling, materials, and sensor systems in a dynamic environment. It extends from crystallizing magmas at 900 C, 50 MPa, and 2100 m depth transitioning upward within 30 m abruptly to solid rock at 350 C and then through a producing geothermal system to ambient atmospheric temperature and pressure at the surface. As well as providing an extreme environment for unprecedented research and for developing the commercial geothermal opportunity of supercritical steam, Krafla will drive innovation from Technology Readiness Level 1 (TRL1), basic scientific principles, to TRL 10, qualified tested and operational technology. 9

10 TRL 1 4 Develop the basic theories of magma crystallization, heat migration and circulation of fluids at a magma rock interface through direct in situ observations. Development of functions to test in situ technology including laboratory simulation and validation of indirect and direct measurement and geophysical models. Outcomes New theories on magma crystallization and heat flux New models for the magma fluid rock interface Feasibility of reducing volume of eruptible magma through energy extraction TRL 3 6 Installation of sensor networks and validation in different geo-environments Joining the best practice in the geothermal and volcanological environment Outcomes New sensor systems for hot, acid and dynamic geological environments Real-time calibrations for operational geophysics including intentional stimulation and detection of volcanic unrest Transfer of application from materials technology TRL 6 10 Demonstration of the use of supercritical steam in an active magma chamber environment Demonstration of use of sensor systems in an active magma environment for enhanced realtime volcano monitoring Outcomes Commercialization of supercritical steam geothermal systems Sensor systems to model and help to predict volcanic eruptions Next steps We are actively engaged in raising 20 m Euros from public- and private-sector sources in multiple countries to launch the first drilling and engineering phase of the KMT. Related scientific investigations have already begun in Italy, Germany, New Zealand, United States and Iceland. 10

11 About the authors Donald Bruce Dingwell is President of the International Association of Volcanology and Chemistry of Earth s Interior and 3rd Secretary General of the European Research Council. He is Director and Professor, Earth and Environment, Ludwig Maximilian University of Munich and was President of the European Geosciences Union. A foremost expert on laboratory measurement of magmatic properties, he is largely responsible for development of the field of experimental volcanology. John C Eichelberger is Principal Investigator for KMT, Professor of Geology at University of Alaska Fairbanks, and Vice President Academic of University of the Arctic. He was Volcano Hazards Program Coordinator for the US Geological Survey. He has served as PI on four scientific drilling projects on volcanoes, and investigator on two others including the successful coring of a 1200 o C lava lake in Hawaii. He received the European Geosciences Union s award for work in natural hazards science in John N Ludden, CBE, is Executive Director of the British Geological Survey and Chair, Earth Science Europe. He has held numerous science direction and management posts, including Director of the Earth Sciences Division at the French National Centre for Scientific Research (CNRS) and President of the European Geosciences Union (EGU). Charles Mandeville is Program Coordinator for the US Geological Survey s Volcano Hazards Program. He manages the five volcano observatories of the US and guides the underlying scientific research and is also a Member of the Steering Committee for the Global Volcano Model. He is well known for his work on magmatic volatiles. Sigurður H Markusson is Geochemist and Project Manager of Landsvirkjun National Power Company s Krafla Geothermal Project. Landsvirkjun, as operator of the Krafla geothermal field and power plant, is the key industrial partner of KMT and has drilled through the rock melting point in three separate boreholes. Paolo Papale is former Director of Volcanology for Italy s Istituto Nazionale Geofisica e Vulcanologia (INGV). He currently leads the Volcano Hazard Centre at INGV where he is responsible for volcano hazard studies and assessment on some of the most active, populated, and dangerous volcanoes in the world. Freysteinn Sigmundsson is Professor of Geophysics at Nordic Volcanological Centre, Institute of Earth Sciences, University of Iceland. He leads and has led a number of major volcanological project consortia in Europe and is widely recognized for his work on volcano deformation and plate tectonics. 11

12 Contact Hjalti Páll Ingólfsson: John Eichelberger: