Gravity collapse structures in the Central Precordillera fold-andthrust belt, Argentina

Several landforms found in the fold-and-thrust belt area of Central Precordillera, Pre-Andes of Argentina, which were often associated with tectonic efforts, are in fact related to non-tectonic processes or gravitational superficial structures. These second-order structures, interpreted as gravitational collapse structures, have developed in the western flank of sierras de La Dehesa and Talacasto. These include rock-slides, rock falls, wrinkle folds, slip sheets and flaps, among others; which together constitute a monoclinal fold dipping between 30º and 60º to the west. Gravity collapse structures are parallel to the regional strike of the Sierra de la Dehesa and are placed in Ordovician limestones and dolomites. Their sloping towards the west, the presence of bed planes, fractures and joints; and the lithology (limestone interbedded with incompetent argillaceous banks) would have favored their occurrence. Movement of the detached structures has been controlled by lithology characteristics, as well as by bedding and joints. Detachment and initial transport of gravity collapse structures and rockslides in the western flank of the Sierra de la Dehesa were tightly controlled by three structural elements: 1) sliding surfaces developed on parallel bedded strata when dipping >30° in the slope direction; 2) Joint’s sets constitute lateral and transverse traction cracks which release extensional stresses and 3) Discontinuities fragmenting sliding surfaces.  Some other factors that could be characterized as local (lithology, structure and topography) and as regional (high seismic activity and possibly wetter conditions during the postglacial period) were determining in favoring the steady loss of the western mountain side in the easternmost foothills of Central Precordillera.

Civic Humanism and the Classical Tradition in the Early Republic of Chile

The first decades of the 19th century constituted a period of profound change for Chile, the principal results of which were to be seen in the consolidation of the process of independence from Spanish dominion in 1818. The consequences were not limited to a revolution of military and political nature; they also included a renovation of the cultural panorama -at least among the educated patriots who made an effort to distance themselves ideologically from the Monarchy-, with the implicit challenge of establishing a new order for Chile, based on legitimate and universally recognizable foundations. The inspirational framework for these efforts is usually associated with other revolutionary examples -France and the United States- that preceded the emancipation processes in Spanish America, as well as with the discourses of illustrated liberalism. As we will attempt to demonstrate in this study, a new reading of the texts written by the Creoles that lead the Chilean independence process may, nonetheless, also reveal the relevance of the classical tradition as a model for the configuration and legitimization of the first Republican projects that especially admired the ideals of Republicanism.