Regional patterns of tectonic stress in Europe

Abstract

Nearly 1500 stress orientation determinations are now available for Europe. The data come from earthquake focal mechanisms, overcoring measurements, well bore breakouts, hydraulic fracturing measurements, and young fault slip studies and sample the stress field from the surface to seismogenic depths. Three distinct regional patterns of maximum compressive horizontal stress (SHmax) orientation can be defined from these data: a consistent NW to NNW SHmax stress orientation in western Europe; a WNW‐ESE SHmax orientation in Scandinavia, similar to western Europe but with a larger variability of SHmax orientations; and a consistent E‐W SHmax orientation and N‐S extension in the Aegean Sea and western Anatolia. The different stress fields can be attributed to plate‐driving forces acting on the boundaries of the Eurasian plate, locally modified by lithospheric properties in different regions. On average, the orientation of maximum stress in western Europe is subparallel to the direction of relative plate motion between Africa and Europe and is rotated 17° clockwise from the direction of absolute plate motion. The uniformly oriented stress field in western Europe coincides with thin to medium lithospheric thickness (approximately 50–90 km) and high heat flow values (>80 m W/m2). In western Europe a predominance of strike‐slip focal mechanisms implies that the intermediate principal stress is vertical. The more irregular horizontal stress orientations in Scandinavia coincide with thick continental lithosphere (110–170 km) and low heat flow (<50 m W/m2). The cold thick lithosphere in this region may result in lower mean stresses associated with far‐field tectonic forces and allow the stress field to be more easily perturbed by local effects such as déglaciation flexure and topography. The stress field of the Aegean Sea and western Anatolia is consistent with N‐S extension in a back arc setting behind the Hellenic trench subduction zone. The stress field is influenced in places by regional geologic structures, e.g., in the Western Alps, where SHmax directions show a slight tendency toward a radial stress pattern. Not all major geologic structures, however, appear to affect the SHmax orientation, e.g., in the vicinity of the Rhine rift system horizontal stress orientations are continuous.

Intraplate seismicity in the western Bohemian Massif (central Europe): A possible correlation with a paleoplate junction

“…The TBU can thus act as an effective guide transmitting stress from the Alps through the rigid upper crust (Müller et al, 1992) to the west Bohemian seismoactive region and even farther to north into the ST (Fig. 5), where, however, much less seismic energy is being released compared to the NK area (Fig.…”

The distribution of rivers to terrestrial sinks: Implications for sediment routing systems

“…The first classification categorizes each internal sub-catchment according to the tectonic regime of the modern terrestrial sink classification as defined by , which represents six main tectonic regimes (Ingersoll, 2012): foreland, passive margin, intracratonic, forearc, extensional or strike-slip. The geographical distribution of these tectonic regimes is derived from published regional and global scale stress-maps, neotectonic maps, plate tectonic boundaries and previous tectonic basin classifications (e.g., Mann and Burke, 1984;Dewey et al, 1986;Watson et al, 1987;Müller et al, 1992;Zoback, 1992;Marsaglia, 1995;Decelles and Giles, 1996;Allmendinger et al, 1997;Honthaas et al, 1998;Bird, 2003;Yi et al, 2003;Yueqiao et al, 2003;Wang et al, 2006;Cunningham, 2010;Hartley et al, 2010;DeCelles et al, 2011;Ingersoll, 2012). The second tectonic regime classification reflects the main tectonic regime of exorheic catchments as it drains to the shoreline based on the work of Nyberg and Howell (2016).…”

Present-day stress field of Southeast Asia

“…included in the description of regional stress fields (Müller et al, 1992;Zoback, 1992;Hillis and Reynolds, 2000).…”

“…Mapping of the plate-scale present-day stress field can reveal key insights into the forces controlling intraplate deformation (Müller et al, 1992;Richardson, 1992;Zoback, 1992;Hillis and Reynolds, 2000). Early phases of the World Stress Map (WSM) and Australian Stress Map projects demonstrated that the first-order intraplate stress field is primarily the result of forces generated at plate boundaries, most importantly mid-ocean ridge 'push', subducting slab 'pull', trench 'suction' and resistance due to continental collision (Forsyth and Uyeda, 1975;Zoback, 1992;Reynolds et al, 2002).…”