Andean deformation and rift inversion, eastern edge of Cordillera Oriental (Guateque–Medina area), Colombia

Abstract

In the Guateque-Medina area, Paleozoic basement and Mesozoic rift basins have been uplifted and exhumed during the Andean orogeny (12 Ma to present). Surface exposures and subsurface data constrain the deformation style and the rift geometry. We have mapped a regional transect and restored a cross section. We have also reconciled existing stratigraphic data, from cordillera, foothills and foreland basin, and have added new data of our own. In Early Cretaceous shales, there is evidence for fault-controlled sedimentation. A brecciated evaporitic layer, which is locally emerald bearing, has acted as a regional detachment. The underlying basement, composed of Paleozoic sediments, crops out as the Quetame Massif. It was uplifted during the Andean orogeny on a series of high-angle reverse faults. The main SE-verging Tesalia fault has resulted from Andean reactivation of an Early Cretaceous normal fault, which bounded a half-rift. A series of NW-verging back-thrusts may have resulted from Andean reactivation of Paleozoic faults. Between the back-thrusts and the Tesalia fault is a basement pop-up. It may be part of a flower structure, because components of right-lateral slip have been identified. These are attributed to eastward subduction of the Nazca plate beneath South America. In general, the style and timing of Andean deformation in the Guateque-Medina area are compatible with the plate tectonic setting of the northern Andes.

Cenozoic contractional reactivation of Mesozoic extensional structures in the Eastern Cordillera of Colombia

“…It has also been interpreted as a lower Cretaceous normal fault [Rowan and Linares, 2000;Branquet et al, 2002] but evidence collected during our field work and investigations by others [Branquet et al, 2002;Rowan and Linares, 2000] do not point toward a significant reactivation, but rather suggest that the fault acted as a buttress. The latter point is suggested by the fact that analogous to the Naranjal and San Juanito faults the Esmeralda Fault separates a shorter wavelength folding domain from the wide basement culmination of the Farallones Anticline (Figure 14).…”

An integrated analysis of an orogen-sedimentary basin pair: Latest Cretaceous-Cenozoic evolution of the linked Eastern Cordillera orogen and the Llanos foreland basin of Colombia

“…Reactivated Mesozoic normal faults, such as the Guaicaramo fault system in the central Llanos foothills, have been considered to be the major boundary of those structural styles. Models of inversion tectonics have been created for the southern segment of the Eastern Cordillera and Llanos foothills (Casero et al, 1997;Rowan and Linares, 2000;Branquet et al, 2002;Restrepo-Pace et al, 2004;Toro et al, 2004;Cortés et al, 2006a;Mora et al, 2006), in the central segment of the Eastern Cordillera and Llanos foothills (Colleta et al, 1990;Dengo and Covey, 1993;Cooper et al, 1995;Cazier et al, 1995;Roeder and Chamberlain, 1995;Rathke and Coral, 1997;FajardoPeña, 1998;Taboada et al, 2000;SarmientoRojas, 2001;Rochat et al, 2003;Toro et al, 2004;Martinez, 2006;Mora et al, 2006), and in the northern segment of the Eastern Cordillera and Llanos foothills (Chigne et al, 1997;Corredor, 2003;Villamil et al, 2004). Although structural models differ both in the angle and depth of detachment of the Guaicaramo fault system and in fault involvement of crystalline basement to the east, structural restorations from the axial zone of the Eastern Cordillera and Llanos Basin are similar (Fig.…”

Eastward extent of the Late Eocene–Early Oligocene onset of deformation across the northern Andes: constraints from the northern portion of the Eastern Cordillera fold belt, Colombia

“…Evidence of this age includes the age of the foreland deposits in the adjacent Eastern Llanos basin and the lack of pre-orogenic sediments that are younger than Middle Miocene ( Van der Hammen et al, 1973;Irving, 1975;Colletta et al, 1990;Dengo and Covey, 1993;Roeder and Chamberlain, 1995;Kammer, 1999;Branquet et al, 2002). However, whether an event of uplift and deformation occurred, which caused thrusting and folding on the western and eastern margin of the Eastern Cordillera during the Late Eocene -Early Oligocene, remains controversial (Schamel, 1991;Laumonier et al, 1996;Gomez et al, 2003).…”