Rodriguez et al 2018 latitudinal and longitudinal patterns of exhumation in the andes of north central chile

Tectonics
10.1029/2018TC004997
Figure 2. (a) Geological map of north-central Chile. Modified from Sernageomin (2003). DHA = Doña Ana Hill, BH = Blanco
Hill.
Since the Late Cretaceous the geological evolution in north-central Chile has been characterized by the
occurrence of major compressive events followed by periods of apparently milder, though uninterrupted
compression (Barnes & Ehlers, 2009; Charrier et al., 2012). However, in Jurassic and Early Cretaceous times,
a tensile stress regime caused generalized extension in the continental margin and the development of wide
backarc extensional basins (e.g., Charrier et al., 2007), to the east of the magmatic arc. According to the outcrop
distribution of Jurassic to Lower Cretaceous volcano-sedimentary and sedimentary rocks (Figure 2),
these extensional basins developed mainly along the border between the present-day Coastal and Main
Cordilleras and the border between the present-day Main and Frontal Cordilleras (Figure 2). Tectonic inversion
of the extensional basins occurred during the Peruvian (late Early to early Late Cretaceous) and the subsequent
“K-T” (Cretaceous- Paleogene boundary) and Incaic (mid-late Eocene) orogenic phases (e.g., Amilibia
et al., 2008). In the studied region, the west vergent Vicuña-San Félix and the east vergent Rivadavia reverse
faults have been joined at depth and interpreted as uplifting the western border of the Main Cordillera northward
from 30°S during the Incaic orogeny (Cembrano et al., 2003; Pineda & Emparán, 2006; Pineda &
Calderón, 2008), building the Incaic Range (Charrier et al., 2007; Charrier et al., 2009). According to
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