Water Chemistry, Geothermometry of the Northern Algerian Sahara in Geothermal System, Case Study Ghardaia, Algeria

Séminaire International sur l′Hydrogéologie et l′Environnement 12 – 14 Mars 2019, Ouargla (Algérie) Water chemistry, Geothermometry of the northern Algerian Sahara in geothermal system, case study Ghardaia, Algeria Mihoub Redouane (1), Amroune Abdelouhab (2), Bekkouche SMA(3) and Rabahi Noureddine (4) (1) Unité de Recherche Appliquée en Energies Renouvelables, URAER, Centre de Développement des Energies Renouvelables, CDER, 47133, Ghardaïa, Algeria (2) Département des sciences agronomiques, Faculté des sciences, Universitaire Mouhamed Boudiaf M’Sila. (3) Unité de Recherche Appliquée en Energies Renouvelables, URAER, Centre de Développement des Energies Renouvelables, CDER, 47133, Ghardaïa, Algeria (4) Département de geologie, Faculté des sciences, Université de Batna -2. E-Mails [email protected] Sbaâ, and Timimoun to the West . The Northern Abstract—Ghardaia, located in the north of the Sahara Aquifer System "SASS" covers an area Sahara in Algeria, and extends over an area of exceeding [1 million (square kilometers)], 60 % in 2 86105 km . The water Wells inventory in the Algeria, 10 % in Tunisia and 30 % in Libya. With study area has reported to 565 Wells which exploit a capacity of up to 1600 m , there are two main the intercalary continental and offering a flow of reservoirs: 3 387.86 hm /year. A chemical study counting data- Intercalary Continental midsole combining land base reveals in this study, that we describe the Lower Jurassic and Lower Cretaceous. physic-chemical characteristics .The isotopic Terminal Complex with carbonate formations indicate a meteoric origin of the thermal water from the Upper Cretaceous to Paleocene and results the estimated temperature ranges between Eocene and Miocene series. 22°C to 45°C, while the cationic geothermometers The geological science is a part of renewable where estimated between 100-500°C. energy it consists in extracting the heat stored in Geothermal represented by several interesting the soil for the production of electricity , clues and corresponding to the northan and north - geothermal science in high temperature [39] or east of the study area. The south marks the areas of the heating , geothermal science in low- geothermal high heat flux. : the main temperature [48]. The magmatic activity has led, characteristics of groundwater in the region in a as soon as the superior Eocene, to the effusion, at regional geological setting and data collected of its summit in basaltic traps to tholïtics affinities. oil Wells contribute that there are an internal The Hoggar in the south of Algeria is a bulge of movement of warm waters through the existing lithospheric scale [33]associated with a hot point . fault network and by contact with rocks create a The Paleozoic series, discordant on the base which convection process. The Ghardaia’s geothermal form the filling of these basins, have significant system is a non-volcanogenetic system. The water thicknesses, often exceeding the 8000 m. The has gained depth. Hoggar is located within the African plate far from Key-Words— Algeria, Ghardaia, geothermal water, the recent East African rift system. Associated mixing, deep circulation. with a swell 1,000 km in diameter, Hoggar Cenozoic volcanism is classically considered to be I. INTRODUCTION a mantle plume product even though no thermal Algerian platform, is the most important basins, it anomaly has been observed [16] ;[23].on average. includes those of Illizi-Berkine , Hassi Messaoud, The advantage and disadvantage of methods Hassi R'mel and Oued Mya (Ghardaia) in the applied in this study is the Treatment of all center, and Tindouf, Bechar, Reggane, Ahnet, existing data enabled us to identify geothermal area and especially to define the relationships with 70 Séminaire International sur l′Hydrogéologie et l′Environnement 12 – 14 Mars 2019, Ouargla (Algérie) characteristics hydro-chemical that may be developed. The rest of this paper is organized as offered, and to build the areas of internal energy follows: Section (2) presents site location and data stored? collection. In section (3) we describe water The aim of this study is to find out the origin of chemistry in section (5) geothemometry, in section the thermal water and possible relationship with (6) concludes the end suggest a future work. the geological and tectonic set of the study area. The studies on the deep aquifers since the beginning of the twentieth century have II. Site Location and Data Collection demonstrated that the underground circuit of thermal waters integrates into the overall Ghardaïa , located in the center of the Northern movement of groundwater. The Temperature Sahara ,600 km, south of the capital Algiers .It is gradient is by definition related to the depth and one of the great oasis in Algeria , it is nature of the rock and hence an average gradient characterized by a vast expanse where rocky may not represent the thermal condition 4° C / 100 outcrops of bare of rock witch blackish brown m. The use of thermal waters in Algeria goes back color. This tray is masked by the strong river to antiquity. In effect, the remnants such as wells erosion early Quaternary who cut in its southern and remnants of public baths were found near hot part of the flat-topped buttes and shaped valleys. It springs as early as 3000 front. J.-C. Subsequently, is located between (3° 40' 38" longitude E - 32° the Roman civilization has made a systematic use 29' 14" N latitude), him surface area is 86 105 of thermal waters and mineral resources for km2. The collected data used in this work ( various uses. The temperature of the soil depends Geothermal data, physic-chemical data, data of on the depth in which is measured, Such as the sun water well, of oil well , temperature, etc.), have rays [38], the ambient temperature and the wind been collected at the Applied Research Unit for speed. In geothermal resource, the mode of Renewable Energies (URAER) , Agency of water transfer of the heat offering exchange surfaces (ADE) ,and Agency hydraulics resources (ANRH), between sufficient this fluid and the rock and the and SONATRACH, situated in the south of possibilities of movement for the heat transfer Algeria (Ghardaia ) . The relief (Fig.1) of Ghardaïa fluid. The water with its physic-chemical and is characterized in to the north by the chain of thermal characteristics constitutes the most rocky (the chabka) and in to the south by effective vector. The thermal waters acquire a new (Hamada)[12]. The altitudes are relatively low; interest for the man and their hydrothermal they gradually declined from up-stream to down- systems represent an energy resource which has stream, especially in the northern part of the area, the advantage of having a low impact on the leads to the formation of many valleys called environment. Algeria with its solar deposit is very dayates, very fertile or sink and join a multitude of important to large opportunities for the Valley. Rock cliffs and the Oasis determine the development of the chain [41]. An optimal use of landscape in which are located the cities of M'Zab solar energy [39] needs an accurate knowledge of and around which revolve other oasis: Berriane, El solar radiation at a particular geological location. Guerrara, Zelfana, Metlili and much more remote Accurate measurement of soil temperature is a in the south ,the oasis of Hassi El Fhel and El difficult task. Heat flux plates can be used to make Golea [9]. The climate of Ghardaia’s area is arid direct measurements of soil temperature [38] .This with a minimum and maximum air temperature work is a general summary of data collected which ranging from (14 - 47 °C) and from (2 - 37 °C) constitutes a state of places of the potentialities of during summer and winter months respectively. geothermal energy in the Ghardaia’s area which The daily Global Solar Radiation (GSR) varies future strategies to recovery of this resource can be between a minimum of (607 Wh/m2/day) to a 71 Séminaire International sur l′Hydrogéologie et l′Environnement 12 – 14 Mars 2019, Ouargla (Algérie) maximum of (7574 Wh/m2/day) and the annual-3) T mean-daily GSR is about (5656 Wh/ m2/day) [18]. he dry residue Represents the total Exceptionally, when the rains are important, mineralization of water "total dissolved salts and especially in the northwest of Ghardaïa, These organic matter content in water" .the variations in Valleys (O. Mzab) drain enormous quantities of south of the study area (El Menia are not water which has estimated between( 205 -722 overloaded 1 - 0.5 g /l the increase from the center m3/s) .The winds are violent and frequent in the to the north " charged water " 1-2.5 g / l. month of February, in June it causes a sand storms. The month of June to September, is the Table1: water chemical ions data (mg/l) from the sirocco how predominate northern part of Algerian sahara (Ghardaia). 4) Reservoir temperature estimation The temperature of the groundwater increases by Figure . 1. Site location of Ghardaia city; (1° C per 30 m) when the thermal gradient is (a)Algeria area, b) Ghardaia area, c) relief (3D) of normal. The temperatures used (Fig.4.) are those Ghardaia area). measured at the level (0) in diverse points in the study area . We note through that the temperature varies with depth, the waters temperature value is III. Water Chemistry influenced by the thermal gradient. The temperatures are increasing from the south (El 1) Potentiel hydrogen (PH) Variations are 7.5 to Golia) to the north of study area (north of 8.8 the water is between neutrality and basicity Berriane ) . The maximum value measured is 45°C northernmost water is more basic 8.8 "northern more in the North, the minimum value measured is Beriane", 7.8 to 8.4 in "the center" , the waters 24°C in the south and the average temperature is have "pH "value 8.3 has higher northernmost so 40°C characterizes the Center of study area.

Load more