Krafla Magma Testbed: An International Project Crossing The Scientific Frontier From Geothermal System Into Magma
Abstract
Few Earth regimes are subject to as much inference and as little direct knowledge as magma. Among the most important mysteries is the transition from hydrothermal to magmatic, i.e. from aqueous fluid-present to silicate melt-present, regimes. Because solid rock is ductile at near-solidus temperature, fractures should have fleeting existence and therefore heat transfer should be by conduction. Heat and mass transport across this zone influences evolution of magma bodies. The hydrothermal regime influences eruptive behavior when magma intrudes it and propagation of the transition zone toward magma is demonstrated by physical and chemical evidence. Both drilling observations and heat-balance considerations indicate that the melt- and fluid-absent transition zone is thin. Drilling of Iceland Deep Drilling Project's IDDP-1, 2 km into Krafla Caldera, showed that the transition from deep-solidus fine-grained granite to liquidus rhyolite is less than 30 m thick, probably much less. For the first time, we have the opportunity to interrogate an entire system of heat and mass transport, from magmatic source through the hydrothermal zone to surface volcanism, and in so doing unite the disciplines of volcanology and geothermal energy. With support from industry, national geoscience agencies, community stakeholders, and the International Continental Scientific Drilling Program (ICDP), we are developing a broad program to push the limits of knowledge and technology in extremely hot Earth. We use the term "testbed" for two reasons: Surface and borehole observations used in volcano monitoring and geothermal exploration will be tested and reinterpreted in light of the first "ground-truth" about magma. More than "observing", magma and the transition zone will be manipulated through fluid injection and extraction to understand time-dependent behavior. Sensor technology will be pushed to measure magmatic conditions directly. Payoffs are in fundamental planetary science, volcano monitoring and geothermal production, and potentially in reduction of eruption risk through direct extraction of thermal energy from magma.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.V51C..03E
- Keywords:
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- 8419 Volcano monitoring;
- VOLCANOLOGYDE: 8434 Magma migration and fragmentation;
- VOLCANOLOGYDE: 8439 Physics and chemistry of magma bodies;
- VOLCANOLOGYDE: 8486 Field relationships;
- VOLCANOLOGY