Hydrodynamic functioning of rhythmic springs: a case of M’Chaki spring (Jijel – NE Algeria)

• Published in: Arabian journal of geosciences Vol. 13; no. 20
• Main Authors: Debieche, Taha-Hocine, Bouzenoune, Azzedine, Zahi, Faouzi, Drouiche, Abdelmalek, Mahdid, Souhil, Rouikha, Youcef, Chine, Amal
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.10.2020; Springer Nature B.V
• Subjects: Carbonates; Discharge; Earth and Environmental Science; Earth science; Earth Sciences; Geology; Hydrodynamics; Original Paper; Reservoirs; Rhythms; Spring; Triassic; Water flow; Water springs; Algeria; Rhythmic spring; Karst; Hydrochemistry; Gauging; Reservoir siphonic
• ISSN: 1866-7511; 1866-7538
• DOI: 10.1007/s12517-020-06082-3

Rhythmic springs are characterized by a rhythmic flow attributable to a hydraulic phenomenon of filling and emptying one or several siphonic reservoirs located upstream of the springs. The M’Chaki spring is the only rhythmic spring in Algeria. The present research was carried out to determine its hydrodynamic functioning on the basis of understanding the hydrodynamic and chemical responses of the spring as well as the geological conditions of the area. Hydrodynamic results indicate that the M’Chaki spring has two types of flow: one is permanent, while the other one is rhythmic, characterized by a cyclicity ranging from 30 min up to 2 h 16 min during the year. Comparison of the spring’s discharge between low and high water periods shows that the discharge of permanent flow varies between 24 and 100 L/s, and the maximum rhythmic flow discharge varies between 70 and 280 L/s, indicating the contribution of rainfalls to supplying the spring. Cycle’s analysis (from 37 up to 60 min) during one day shows that the rhythmic flow is linked to 3 siphonic reservoirs. Hydrochemical study confirmed the obtained hydrodynamic results and indicated that the origin of the permanent water flow is less superficial than the rhythmic water flow. It mentioned also that the siphonic reservoirs were carved in Triassic brecciated formations and highly fractured Liassic carbonate formations. Combining geological, hydrodynamic and hydrochemical data enabled us to propose a conceptual scheme to reveal the disposition of siphonic reservoirs and to explain the functioning of the M’Chaki spring.