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The Villarrica Volcano is one of the most active volcanoes in South America and is located in a major tourism region. A dense temporal seismological network was installed to investigate the volcanic seismicity and the seismic structure of the edifice with seismic traveltime tomography at high spatial resolution. The network was in operation for 2 weeks from 01.03.2012 to 14.03.2012. It consisted of 30 three-component and 45 one-component short period seismographs covering an area of about 2000 km2. The covered area has a diameter of 45 km and includes the volcanic building.

The Villarrica Volcano is one of the most active volcanoes in South America and is located in a major tourism region. A dense seismological network is used to investigate the seismic characteristics of the volcano and its seismic structure tomographically with high spatial resolution. The network was in operation for 2 week from 01.03.2012 to 14.03.2012. It consisted of 30 3-component and 45 1-component short period seismographs covering an area of 2000 km*2. The covered area has a diameter of 45 km and includes the volcanic building.

The DESCRAMBLE project, which developed a proof-of-concept test of reaching deep geothermal supercritical resources, has been an occasion to improve knowledge of deep chemical-physical conditions for predicting and controlling future drilling activities. The test site has been an existing dry well in Larderello, Italy, already drilled to a depth of 2.1 km and temperature of 350 °C, which was deepened to intersect a seismic marker at almost 3 km depth. Down at the final depth of 2.9 km, in the middle of the seismic reflections, an unexpected extremely high temperature was measured (507- 517°C at 2.9 km). This value, associated with the geological conditions of the rocks, with a leak off pressure of about 30 MPa (300 bar), can pave the way for a further utilization of this well for an EGS system, producing supercritical fluids from reinjected water.

The DESCRAMBLE project has developed novel drilling technologies for a proof-of-concept test of reaching deep geothermal supercritical resources. In the project, we have drilled and tested the continental-crust condition for demonstrating novel drilling techniques, the control of gas emissions and high temperature/pressure conditions expected from the deep fluids. The project has also improved knowledge of deep chemical-physical conditions for predicting and controlling future drilling conditions. The test site has been an existing dry well in Larderello, Italy, already drilled to a depth of 2.2 km and temperature of 350 °C, which was deepened to 3 km depth reaching supercritical conditions. The productivity and efficiency of the project were ensured by the combination of industrial and research participation and by the recognized expertise of the consortium in geothermal R&D as well as oil and gas drilling, combining excellence in both sectors. DESCRAMBLE's results will be presented in this paper, covering all the main aspects of the project: drilling procedures, material, well control, mud logging, well testing, modelling, geochemical and geophysical surveys and monitoring, petrographic and petrophysical evaluations and very high temperature and pressure logging tool.

Information on both hydraulic and thermal conditions of the subsurface is fundamental for the planning and use of hydrothermal energy. This is paramount in particular for densely populated international border regions, where different subsurface applications may introduce conflicts of use and require reliable cross-border management and planning tools. In the framework of the Interreg4a GeoPower project, fundamental geological and geophysical information of importance for the planning of geothermal energy utilization in the Danish-German border region was compiled and analyzed. A 3D geological model was developed and used as structural basis for the set-up of a regional temperature model. In that frame, new reflection seismic data were obtained to close local data gaps in the border region. The analyses and reinterpretation of available relevant data (old and new seismic profiles, core and well-log data, borehole data, literature data) and a new time-depth conversion (new velocity model) allowed correlation of seismic profiles across the border. On this basis, new topologically consistent depth and thickness maps for 12 geological/lithological units were drawn, with special emphasis on potential geothermal reservoirs, and a new 3D structural geological model was developed. The interpretation of petrophysical data (core data and well logs) allows to evaluate the hydraulic and thermal rock properties of geothermal formations and to develop a parameterized 3D thermal conductive subsurface temperature model. New local surface heat-flow values (range: 72−84 mW/m2) were determined and predicted temperature were calibrated and validated by borehole temperature observations. Finally, new temperature maps for major geological sections (e.g. Rhaetian/Gassum, Middle Buntsandstein) and selected constant depth intervals (1 km, 2 km, etc.) were compiled. As an example, modelled temperatures for the Middle Buntsandstein geothermal reservoir are shown with temperatures ranging between 24 and 192 °C for depths of interest.