Late Quaternary evolution of the La Cantera Fault System (Central Precordillera, Argentina): A morphotectonic and paleoseismic analysis

摘要: Abstract The La Cantera Fault System (LCFS) is the most active Quaternary structure in Central Precordillera of San Juan, central-western Argentina; system extends for 47 km along intermountain valley that separates Sierra de and Invernada, north Juan River. average fault trend 20°; it dips at angles varying between 15° 30° W northern section, to approximately 40° central up 60° southern section. affects Holocene recent alluvium deposits western piedmont defined by a series landforms found compressive tectonic environments, including simple compound counterslope scarps, staircased alluvial terraces, sag ponds, flexural aligned springs, broom-shaped drainage patterns, river diversions, beheaded channels, changes incision depths, sinuosity gradient channels. Trench investigations indicated least three events occurred past 1.1–10.1 ky. topographic profiles selected channels interfluves cutting across trace were analyzed using Stonex Vector GPS differential establish relationship topography slope rivers. This morphometric analysis scarps indicates tectonics have played an essential role controlling pattern piedmont, leading rivers adjust these variations. Based on geomorphologic, stratigraphic structural characteristics, LCFS considered be relevant seismogenic source intraplate portion South America, with recurrence interval 2000 ± 500 years moderate magnitude earthquakes during last 11,000 years.