Tectonics modify the base-level of rivers and result in the progressive erosion of landscapes. We propose here a new method to classify landscapes according to their erosional stages. This method is based on the combination of two DEM-based geomorphic indices: the hypsometric integral, which highlights elevated surfaces, and surface roughness, which increases with the topographic elevation and the incision by the drainage network. The combination of these two indices allows one to produce a map of erosional discontinuities that can be easily compared with the known structural framework. In addition, this method can be easily implemented (e.g., in MATLAB) and provides a quick way to analyze regional-scale landscapes. We propose here an example of a region where this approach becomes extremely valuable: the Ore Mountains and adjacent regions. The lack of young stratigraphic markers prevents a detailed analysis of recent fault activity. However, discontinuities in mapped geomorphic indices coupled to the analysis of river longitudinal profiles suggest a tight relationship between erosional discontinuities and main tectonic lineaments.Remote Sens. 2014, 6 7972
The Sierra Madre de Chiapas evolved in the vicinity of the triple junction between the Cocos, North America and Caribbean plates. The Sierra Madre de Chiapas tectonics reflects positive topographic growth along its main core and a northwards-directed collapse through a free border related to the Gulf of Mexico. Major exhumation and topographic growth occurred during the middle–late Miocene (16–10 Ma). Evidence for this deformational event is provided by fault activity, major stratigraphic unconformities along the Sierra Madre de Chiapas and the Tabasco coastal plain (i.e. southern Gulf of Mexico), major salt-related motion, northward progradation of the sedimentation and northward migration of the buried deformational front. During the Neogene, strike-slip deformation and its related exhumation migrated landwards from the western edge of the Chiapas massif complex to the Chiapas Sierra. Horizontal displacement along the main strike-slip faults in the Chiapas Sierra has been indirectly estimated to be between 30 and 43 km during the last 6–5 Ma, implying 0.5–0.8 cm a
−1
of lateral accommodation. These values suggest that a significant amount of the motion transferred by the Caribbean and North American plates is currently being accommodated along the Chiapas area.
Supplementary material:
A geological map of the Sierra Madre de Chiapas is available at
www.geolsoc.org.uk/SUP18507
.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.