Evolution morphologique du littoral des Chtouka ouest (Maroc), depuis l'ouljien

Abstract : With its southern latitude position (30 n), "the Western Chtouka region" shows the characteristics of a sub-arid environment. in the past, the western Chtouka littoral received an important flow of sandy sediments and still does toda during the successive droughts which hit the region, this aeolian action has become greathly predominant. a clear altera of the morphodynamic as thus teken place over some decades. the study of the existing dunes systems shows that dunes mov the coast towards the interior of the region. The sedimentary evolution expresses it self during the transport by a prog decreasing of the grain size, an impoverishment of the carbonate contents and a growing aeolisation of quartz grains. The study of the morphological inheritances of this coast, clarified by both the morphosedimentary analysis and a 14 c chronology, allowed us to understand the main features of the landscapes evolution from the ouljian (=Eemian) until now. Ouljian dune systems, besides the dynamic factors, the eustatic causes are at the origin of the edification of these san the western Chtouka coast. Eight dune systems have been identified, the oldest studied here being attributed to the late followed by the soltanian (=Weichselian), mellahian, and holocene systems. The formation of this post-ouljian sand depos been controlled by the sedimentation-subsidence balance. and its essentielly linked to the fluctuations of the ocean lev of morphodynamic activity which have been kept allowed us to follow more or less precisely the evolution of the palaeo-l particularly at the upper soltanian and holocene. Today, the degradation of this environment is increased by the anthrop especially since historical periods. The degradation of the argania sp. forest is the most striking evidence of it.
Document type :
Theses
File URL :
http://docnum.univ-lorraine.fr/prive/BUL_T_1996_0005_BARRADA.pdf
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01776549
Contributor : Administrateur Du Ccsd <>
Submitted on : Tuesday, April 24, 2018 - 4:02:51 PM
Last modification on : Wednesday, April 25, 2018 - 1:32:26 AM

Identifiers

  • HAL Id : tel-01776549, version 1

Collections

Citation

Mohamed Barrada. Evolution morphologique du littoral des Chtouka ouest (Maroc), depuis l'ouljien. Géographie. Université Nancy 2, 1996. Français. ⟨NNT : 1996NAN21005⟩. ⟨tel-01776549⟩

Share

Metrics

Record views

18