Palaeogeothermal Study of Idjeran M'Zab and Amguid-El Biod Hassi Messaoud Ridge (Central Sahara, Algeria) – Relationship with Deep Tectonics

B25 PALAEOGEOTHERMAL STUDY OF IDJERAN M’ZAB AND AMGUID-EL BIOD HASSI MESSAOUD RIDGE (CENTRAL SAHARA ALGERIA) – RELATIONSHIP WITH DEEP TECTONICS The Algerian central Sahara consists of two ridges which extend in a submeridian 1 direction from the Hoggar to the Sahara Atlas. Gassi touil and Rhourde Nouss areas are located on the high Amguid el biod Hassi messaoud ridge in the triassic basin horsts. The tectonic study revealed two important tectonic phases (Hercynian and autrichian) that affected differently these two regions. The autrichian phase is noticeable in the Gassi Touil region especially as it is unusual in the saharian level