Assessment of deep geothermal research and development in the Upper Rhine Graben

Abstract

Deep geothermal energy represents a key element of future renewable energy production due to its base load capability and the almost inexhaustible resource base. Especially with regard to heat supply, this technology offers a huge potential for carbon saving. One of the main targets of geothermal projects in Central Europe is the Upper Rhine Graben, which exhibits elevated subsurface temperatures and reservoirs with favorable hydraulic properties. Several decades of intensive research in the region resulted in a comprehensive understanding of the geological situation. This review study summarizes the findings relevant to deep geothermal projects and thus provides a useful working and decision-making basis for stakeholders. A total of nine geological units have been identified that are suitable for deep geothermal exploitation, comprising the crystalline basement, various sandstone formations and Mesozoic carbonates. An extensive lithostratigraphic, structural, geochemical, hydraulic and petrophysical characterization is given for each of these potential reservoirs. This paper furthermore provides an overview of the available data and geological as well as temperature models.

Optimizing scenarios of a deep geothermal aquifer storage in the southern Upper Rhine Graben

“…The Upper Rhine Graben (URG), central part of the European Cenozoic Rift System, is approximately 300 km long and 30 to 40 km wide and has a laterally highly variable tectonic setting (Frey et al 2022). In the southern and central part of the URG the main strike direction is NNE-SSW and in the northern part roughly N-S.…”

Spatial Pattern of the Seismicity Induced by Geothermal Operations at the Geysers (California) Inferred by Unsupervised Machine Learning

“…However, some limitations to this technology should be considered: appropriate locations require a deep geological assessment to better evaluate the economic potential of sites for their extensive exploitation with new installations, as reported in [18], which serves as a useful working and decision-making basis for stakeholders. Besides, nowadays it is difficult to fully understand the legal system regarding geothermal energy in a given European country [19] without some acquaintance with the overarching EU framework [20].…”

Pre- to early-rift thermal conditions of the Upper Rhine Graben using geological and organic geochemical controls

“…The Upper Rhine Graben (URG) is a Cenozoic intracontinental rift with significant local thermal anomalies. Historically, it was the focus for research on hydrocarbon resources and more recently on deep geothermal energy (e.g., Frey et al, 2022aFrey et al, , 2022b. This is precisely the case for the Pechelbronn sub-basin, located in the western central part of the URG, which was mentioned as early as the end of the 15 th century for its hydrocarbon resources (Schwarz, 2021) and hosts a geothermal field studied since the end of the 19 th century (Gérard and Kappelmeyer, 1987).…”

“…In addition, the same control factors are involved in evaluating petroleum systems, which depend on burial, time and temperature (e.g., Philippi, 1965;Welte, 1966;Bajor et al, 1969). Consequently, because the URG is one of the main targets of geothermal projects in Central Europe (Frey et al, 2022a), it is essential to reconstruct the evolution of its burial and thermal history. Generally, thermal maturity assessment of organic matter allows calibration of the burial and thermal reconstructions.…”