2024-03-28T15:17:22Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1769032020-09-02T14:53:04Zcom_10261_123com_10261_8col_10261_502
00925njm 22002777a 4500
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Camafort Blanco, Miquel
author
Booth-Rea, Guillermo
author
Pérez, J. Vicente
author
Melki, F.
author
Gràcia, Eulàlia
author
Azañón, José Miguel
author
Ranero, César R.
author
2017-04-23
Active tectonics in North Africa is fundamentally driven by NW-SE directed slow convergence between the Nubiaand Eurasia plates, leading to a region of thrust and strike-slip faulting. In this paper we analyze the morphometriccharacteristics of the little-studied northern Tunisia sector. The study aimed at identifying previously unknownactive tectonic structures, and to further understand the mechanisms that drive the drainage evolution in this regionof slow convergence. The interpretation of morphometric data was supported with a field campaign of a selectionof structures. The analysis indicates that recent fluvial captures have been the main factor rejuvenating drainagecatchments. The Medjerda River, which is the main catchment in northern Tunisia, has increased its drainage areaduring the Quaternary by capturing adjacent axial valleys to the north and south of its drainage divide. Thesecaptures are probably driven by gradual uplift of adjacent axial valleys by reverse/oblique faults or associatedfolds like El Alia-Teboursouk and Dkhila faults. Our fieldwork found that these faults cut Holocene colluvial fanscontaining seismites like clastic dikes and sand volcanoes, indicating recent seismogenic faulting. The growth andstabilization of the axial Medjerda River against the natural tendency of transverse drainages might be causedby a combination of dynamic topography and transpressive tectonics. The orientation of the large axial Medjerdadrainage that runs from eastern Algeria towards northeastern Tunisia into the Gulf of Tunis, might be the associatedto negative buoyancy caused by the underlying Nubia slab at its mouth, together with uplift of the Medjerdaheadwaters along the South Atlassic dextral transfer zone
Geophysical Research Abstracts 19: EGU2017-16770 (2017)
http://hdl.handle.net/10261/176903
Active tectonics and drainage evolution in the Tunisian Atlas driven by interaction between crustal shortening and slab pull