ORIGINAL_ARTICLE
Hydrothermal waters from karst aquifer: Case study of the Trozza basin (Central Tunisia)
Tunisia is rich in geothermal resources from ancient civilizations. Hydrothermal activity in Tunisia has been related to three main stages: magmatic and tectonic activities, eustatisme (Atlantic and Mediterranean coupling) and climate change. The principal factor and the responsable of this phenomenon is the meteoric water by piston flow processes. It constitue the catalyst of volcanism. The Trozza basin, well known since the Roman period for the importance of its thermo-mineral waters, is characterized by a large occurrence of thermal fluid discharges whose main thermal aquifer. Hydrochemical pattern is mainly controlled by the dissolution of evaporitic sediments (halite, gypsum and/or anhydrite) as well as by the incongruent dissolution of carbonate minerals. This reservoir represents the only vapor hydrothermal system in Tunisia. It is constitute the deepest formation cropping out in the study area. The Triassic deposits and the filonic of Pb-Zn/S caused the contamination of the Continental Intercalaire thermal water in this reservoir. The upwelling of the deep groundwater to the shallow level and discharging also in karst caves of the carbonates minerals. This carbonate reservoir of thermal water (≈ 50 °C), consist of emissions of hot air and vapors and represent a unique case gas hydrothermal karst in Tunisia. It plays a role in the attraction for local population and tourists. But the use of geothermal energy is still in its juvenile stage. Presently, the thermal waters are a resort for wellness, fitness and therapeutic purposes. Kairouan basin, in particular, has numerous thermo-mineral springs, the majority of which are used for public baths, swimming pools, and for medical treatments provided by thermal establishments. Previous studies have shown that location and chemical composition of these thermal manifestations are strongly influenced by the regional geology, the tectonic and the climate impact.
https://jtethys.journals.pnu.ac.ir/article_4188_632c036d03a60a3244fa4a75f47aba04.pdf
2017-03-01
33
44
Thermal water
Karst aquifer
Trozza basin
Tunisia
ORIGINAL_ARTICLE
Hydrogeochemistry of hydrothermal waters from Salams magma chamber: Case study of Isti Su hot spring, NW of Iran
The Isti Su hot spring is located in southeast of Salmas, in Western Azerbaijan, Iran. The area is a small part of Sanandaj-Sirjan geological zone which hosts many hot springs. The magma chamber of Salmas region is the main heat source of the hot springs in Isti Su area. Abundant rainfall and relatively long duration of snowfall as well as several deep faults in the area create the best conditions to have several hot springs in the area. The host rocks of the area are sedimentary and metamorphic rocks of Cambrian to Recent sediments which are intruded by several granite and ophiolite bodies. Several hot springs have been formed in the vicinity of these plutonic to sub-volcanic bodies. The Isti Su hot spring is one of the most typical hot springs of the Salmas region. Eight samples were collected from the study area. In order to investigate the seasonal changes in the field and chemical parameters and to measure trace element concentrations in dry and wet seasons, springs were sampled twice in May and November. Temperature, pH and electrical conductivity (EC) of the water samples were measured on-site. Temperatures of the selected samples range from 26.3 °C to 38.5 °C. The pH values of the samples vary between 6.4 and 7.5. TDS contents range from 9200 to 1790 mgL-1. The results of geochemical analysis show that the As, Li, Fe, Hg, Na, and Cr are not more than WHO’s standard level. As and B are two times more than WHO’s standard level. The As and B concentrations in the hydrothermal and geothermal solutions rise higher than its standard level. WHO’s recommended As level for drinking water is 0.01 mg/l-. The Na-SO4-HCO3 triangular diagram shows that the samples are of HCO3 and Na types. Open skin scars, gangrene, malignant cancers and environmental problems are among the consequences of high concentrations of As and B. The high content of As and B in water of this hot spring can be harmful to the environment and people of the area.
https://jtethys.journals.pnu.ac.ir/article_4189_78b847a96eb543c23c81b2262e7cea97.pdf
2017-03-01
45
52
Hydrogeochemistry
toxic elements
hot spring
Salam
Iran
ORIGINAL_ARTICLE
Investigation geophysical by Magnetometry and Modeling Iron Ore desposit Bijar Kurdestan province
Iron ore deposit Bijar area is located in east north in Kordestan province based of field observation, ore minerals are magnetite, magnetite-martitite and magnetite-pyrite. No. 922 points on the 16 profiles were collected over about 7500 meters in the area. Magnetometers treatment of advanced devices and new GSM-19T is made in Canada. The data were corrected and the magnetic field intensity map was prepared.The remaining amount was calculated regional field and deposit modeling was performed using reverse Euler and accordingly, in this area a mass burial was diagnosed with high magnetism. Due to the intensity of the magnetic field taken, This mass has a high content of metals and minerals are similar and based on geophysical data, location drilling boreholes, to deposit at least depth, have been proposed.
https://jtethys.journals.pnu.ac.ir/article_4213_5867de14b0c49f4c129944a9d4e32286.pdf
2017-03-01
53
60
Magnetic Surveys
modeling
Euler Method
Bijar
ORIGINAL_ARTICLE
Using secondary minerals in Sahneh ophiolitic complex, west Iran
Kermanshah ophiolite is an extremely crushed ophiolitic complex in which a complete ophiolitic sequence is not observed. Gabbros, deloritc dikes and mostly serpentinized peridotites are among the most important constituents of these ophiolitic set. Pridotites existing in the study area are of metamorphosized types that have been severely affected by the hydrothermal solutions due to their extremely crushed conditions and have tolerated almost a severe alteration. Such decompositions and destructions result in creation of secondary minerals of the serpentine group (lizardite, chrysotile, antigorite), clorite, talc, magnesite, iddingsite and brusite). A survey of the secondary minerals existing in the pridotites show that the study area has been undergone a low temperature metasomatism at the green schist face level and then the region temperature has risen up to the amphibiolitic face level due to metamorphosization. In this paper the conditions and the reactions relating to the formation procedure of any of the above said minerals have been surveyed.
https://jtethys.journals.pnu.ac.ir/article_4236_e8e5ab924fa1d95058ad8bd7f314dc16.pdf
2017-03-01
61
69
Metamorphosization
Ophiolitic complex
Secondary minerals
Serpentine group
ORIGINAL_ARTICLE
Earthwork Volume Optimization Using Imperialistic Competitive Algorithm to Minimize Energy Consumption of Agricultural Land Leveling
Land leveling is one of the most important steps in soil preparation for consequent objectives. Parallel policies need to take both energy and environmental subjects into the account as well as certain financial development and eco-friendly protection. Energy is one of the most important elements in agricultural sector. Nevertheless, pollution is linked with the usage of fossil fuels (particularly gasoline) as an energy source. Earthwork optimization plays an important role in reducing the total cost of highway projects. In this research, ICA has been followed to optimize earthwork volume for minimizing energy consumption of agricultural land leveling compared to minimum least squares, genetic algorithm, particle swarm optimization (PSO) have been employed for developing of optimization the energy related and other parameters. The study was specified based on the proposed land leveling project in district of Ahwaz, Iran. The study farm was a 70 ha area and located in the west of Iran. Topography of the farm was mapped in the scale of mapping as fine as 1:500. The outputs of the plan were length, width and height of points (coordinates of x, y and z) and the grid size in the region was 20 m×20 m. The aim of this work was use of new techniques and specifically optimization methods such as Imperialist competitive algorithm, genetic algorithms and PSO in modeling the leveling plane to minimize cut and fill volume and consequently the amount of energy consumption of leveling operations. It has been assumed that soil cut and fill volumes are equal and no need to move/ remove excessive soil. Therefore, there is no need to define a cut/fill variable in the model based on ICA. The results indicated that ICA offers a plan of earthwork, minimizing energy consumption of land leveling more efficiently than minimum least squares, genetic algorithm and PSO.
https://jtethys.journals.pnu.ac.ir/article_4241_18223d4f6788f5a90c7ee245601a18b1.pdf
2017-03-01
70
86
Optimization
Land leveling
Imperialistic Competitive Algorithm
Earthwork
Cut-Fill Volume (V)
Energy
ORIGINAL_ARTICLE
The Late Cenomanian-Coniacian Gattar and Aleg reservoirs in Sidi Bouzid area, Central Tunisia: Logging, diagenesis and reservoir implications
At the Sidi Bouzid area located in Central Tunisia, Cenomanian-Turonian reservoir rocks are well outcropping, especially in the Jebel el Kébar and Meloussi areas. The present work confirms that these carbonate intervals constitute the lateral equivalent of the Early-Middle Turonian Biréno and Late Turonian-Coniacian Douleb reservoir Members which are included within the pelagic marls of the Turonian-Early Campanian Aleg Formation. In addition to the Late Cenomanian-Early Turonian Gattar dolomites, the Biréno and Douleb fractured carbonates constitute, in this area, good reservoirs and thus potential targets in subsurface since they produce oil to the East in Sfax area or in the Gulf of Gabès. Detailed sedimentological, petrographic and petrophysical studies carried out from several sections surveyed at Jebel el Kébar and Jebel Meloussi have focused on the vertical stacking of the carbonate series, thickness, geometry, composition and pore types within the main Cenomanian-Turonian reservoir layers. However, at a North-South transect, these reservoir layers are characterized by frequent and rapid changes in facies and thickness from Jebel el Kébar to Jebel Meloussi and within the Jebel el Kébar itself. These lateral changes appear in close relation with the particular paleogeographic setting which could be governed by several processes such as sea level changes and, especially, contemporaneous tectonic activities. The latter have strongly influenced the reservoir thickness and properties. Furthermore, this study focuses on the origin of fluids controlling the main diagenetic processes (e.g., dolomitization and dissolution) and on the pore type, volume and their interconnection. These latter could be a part of the reservoir aspect characterization. Moreover, attention will also be paid to the spatio-temporal distribution of the Cenomanian-Turonian carbonate Members which would be served as an analog for reservoirs in the Sidi Bouzid area (Central Tunisia) and elsewhere (e.g., African Tethyan margin, North America, and Middle East).
https://jtethys.journals.pnu.ac.ir/article_4243_6641a218dc815c54c48a2bc2448ed898.pdf
2017-03-01
87
102
Cenomanian-Turonian series
Diagenetic processes
Pore system
Reservoir characterization
Central Tunisia