**2. Geology of the north of Algeria centre**

Region consists of structural and sedimentary units showing an imprint of the Alpine tectonics. From north to south there are: the Tell Atlas, varied and complex area. It includes an internal zone and an outer zone formed of non-native land (thrust sheets). Between the two Atlas (Tellian and Sahara) are flush with the High Plains ending to the east by the chain of Hodna and continue to the west by the Oran Meseta (**Figure 3**). The sedimentary formations covers are of Mesozoic and Cenozoic age and based on a diverse base involved in the fold [1].

The warm and sulfurous waters of Hammam Ksana emerge from the bowels of the geological layers of the Triassic and Jurassic of the rocky peaks of the Bibans. The source it self is located at 500 m altitude on a slope of Wadi Tazdart, douar of El Mehir.

#### **Tellian area**:

Characterized by a stack of thrust sheets with associated intra-mountain basins Sedimentary formations blankets are Mesozoic and Cenozoic age and based on a diverse base involved in the folding.

#### **Saharan area:**

Relatively stable or tectonics is less pronounced (**Figure 4**).

**Figure 3.** *Geological units of the northern Algeria.*

#### **Figure 4.**

*Relationship between the different structural units of the chain of Maghrebides (modified from Durand-Delga, 1969 Bibans and Babors who were considered the aboriginal also include tablecloths Tellian).*
