Environmental dynamics and land occupation in the Saharan margins of the Holocene Maghreb

Jean-Louis Ballais (1, 2) , Mohamed Tahar Benazzouz (3) , Aïcha Benmohammadi (4)

1 Université de Provence - UFR Sciences Géographiques et de l'Aménagement
2 ESPACE - Études des Structures, des Processus d’Adaptation et des Changements de l’Espace
3 UMC - Université frères Mentouri Constantine I
4 UIT - Université Ibn Tofaïl

It appears that the moist phase of the Lower Holocene came early and aridity tended to disappear in the Late Ice Age. From this point of view, the chronology of the pre-Saharian Maghreb is considerably closer to that used for the tropical Sahara. Along the same lines, the short arid phase around 7500-7000 BP is similar to what has been observed in the Sahel. On the other hand, concerning the importance of the moist phase after 7000 BP, we must look toward the European Atlantic chronology. .Along the same lines, the accumulation of the lower terrace appears for the most part to be contemporary to the "main holocene fill" of the southern French Alps. For the Prehistoric Upper Holocene, the tropical Saharan chronology becomes evanescent, due to the increase in aridity. Clues indicating a more moist climate than today have been found, however, for around 2000 and 1500 BP, in different spots in the Sahara, notably around Tibesti and in Sudan. Furthermore, the small amount of evidence currently recognized in the pre-Saharan Maghreb is not yet sufficient for a systematic comparison with the European chronology, although the clues are promising.

Keywords: eolian sands; ergs; alluvial terraces; climate

Domains: Environmental Sciences; Humanities and Social Sciences; Geography

Jean-Louis Ballais, Mohamed Tahar Benazzouz, Aïcha Benmohammadi. Environmental dynamics and land occupation in the Saharan margins of the Holocene Maghreb. Environmental Dynamics and History in Mediterranean Areas, Apr 2002, Paris, France. pp.341-351. ⟨hal-01569786⟩