Abstract
GNSS observations constitute the main tool to reveal Earth’s crustal deformations in order to improve the identification of geological hazards. The Ecuadorian Andes were formed by Nazca Plate subduction below the Pacific margin of the South American Plate. Active tectonic-related deformation continues to present, and it is constrained by 135 GPS stations of the RENAGE and REGME deployed by the IGM in Ecuador (1995.4–2011.0). They show a regional ENE displacement, increasing towards the N, of the deformed North Andean Sliver in respect to the South American Plate and Inca Sliver relatively stable areas. The heterogeneous displacements towards the NNE of the North Andean Sliver are interpreted as consequences of the coupling of the Carnegie Ridge in the subduction zone. The Dolores–Guayaquil megashear constitutes its southeastern boundary and includes the dextral to normal transfer Pallatanga fault, that develops the Guayaquil Gulf. This fault extends northeastward along the central part of the Cordillera Real, in relay with the reverse dextral Cosanga–Chingual fault and finally followed by the reverse dextral Sub-Andean fault zone. While the Ecuadorian margin and Andes is affected by ENE–WSW shortening, the easternmost Manabí Basin located in between the Cordillera Costanera and the Cordillera Occidental of the Andes, underwent moderate ENE–WSW extension and constitutes an active fore-arc basin of the Nazca plate subduction. The integration of the GPS and seismic data evidences that highest rates of deformation and the highest tectonic hazards in Ecuador are linked: to the subduction zone located in the coastal area; to the Pallatanga transfer fault; and to the Eastern Andes Sub-Andean faults.
Highlights
The subduction of oceanic plates at convergent tectonic boundaries is responsible for the release of more than 90% of the total seismic moment, mainly occurring along the subduction interface [1,2] and the development of first-order large elongated cordilleras [3]
Convergent continental boundaries may undergo extension adjacent to shortening in fore-arc basins, as seen in Baja California [13,14]. These processes occur in the Ecuadorian Andes (Figures 1 and 2), where the North Andean Sliver [15,16] is affected by shortening and extension and displaced northeastward from the South American Plate, favored by the displaced northeastward from the South American Plate, favored by the Chingua Cosanga–Pallatanga–Puná fault system [16] (Figure 1e)
Discussion o the structures that accommodate deformation involving the main active faults and do mains of the South American Plate margin in Ecuador has led to different pr2oopfo1s7als [2,16 18] (Figure 1)
Summary
The subduction of oceanic plates at convergent tectonic boundaries is responsible for the release of more than 90% of the total seismic moment, mainly occurring along the subduction interface [1,2] and the development of first-order large elongated cordilleras [3]. Convergent continental boundaries may undergo extension adjacent to shortening in fore-arc basins, as seen in Baja California [13,14] These processes occur in the Ecuadorian Andes (Figures 1 and 2), where the North Andean Sliver [15,16] is affected by shortening and extension and displaced northeastward from the South American Plate, favored by the displaced northeastward from the South American Plate, favored by the Chingua Cosanga–Pallatanga–Puná fault system [16] (Figure 1e). Discussion o the structures that accommodate deformation involving the main active faults and do mains of the South American Plate margin in Ecuador has led to different pr2oopfo1s7als [2,16 18] (Figure 1)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.