Late Quaternary Intraplate Deformation Defined by the Las Chacras Fault Zone, West‐Central Argentina

Abstract

Quaternary Andean backarc deformation within the Pampean segment (27-33.5°S) related to the convergence of the Nazca and South American plates is widely distributed, extending up to 700 km east from the Perú-Chile trench (Figure 1a). The plate margin encompasses the thin-skinned fold-and-thrust belts of the Andean Main Cordillera, Frontal Cordillera, and Precordillera in the west, and the thick-skinned reverse faults of the Sierras Pampeanas in the east (Figure 1b). This wide distribution and partitioning of deformation among structures with different tectonic styles has been associated with subduction of a shallowly dipping section of the Nazca plate at these latitudes, known as the Pampean flat-slab segment (Figure 1b;

Reactivation Potential of Intraplate Faults in the Western Quebec Seismic Zone, Eastern Canada

“…Similarly, the short temporal coverage of instrumental seismicity records is not enough to create an inventory of detailed earthquake source models and to determine earthquake recurrence intervals in intraplate regions. However, we know from global examples that large earthquakes are far more common than previously thought in "stable continental regions" (Calais et al, 2016;Rimando et al, 2021). In eastern North America, instrumental, historical, and paleoseismic records show that the region has been shaken by devastating earthquakes, such as the 1929 MS 7.2 Grand Banks and the 1811-1812 MW 7.2-8.2 New Madrid earthquakes) (Bent, 1995;Hasegawa & Kanamori, 1987;Tuttle, et al, 2002).…”