Hydrogeophysical and Structural Investigations Using VES: A Case Study of Dosso Region in the Southwestern Part of the Meso-Cenozoic Iullemmeden Basin (Southwestern Niger)  

作　　者：Abdou Ali Ibrahim Huguette C. Emvoutou Alain Zanga Konaté Moussa Serigne Faye Abdou Ali Ibrahim;Huguette C. Emvoutou;Alain Zanga;Konaté Moussa;Serigne Faye(Department of Life and Earth Sciences, Ecole Normale Supérieure, Université Abdou Moumouni, Niamey, Niger;Department of Earth Sciences, Faculty of Sciences, University of Douala, Douala, Cameroon;Department of Geology, Faculty of Sciences and Techniques, University Cheikh Anta Diop of Dakar, Dakar, Senegal;Department of Geology, Faculty of Sciences and Techniques, Université Abdou Moumouni, Niamey, Niger)

机构地区：[1]Department of Life and Earth Sciences, Ecole Normale Supérieure, Université Abdou Moumouni, Niamey, Niger [2]Department of Earth Sciences, Faculty of Sciences, University of Douala, Douala, Cameroon [3]Department of Geology, Faculty of Sciences and Techniques, University Cheikh Anta Diop of Dakar, Dakar, Senegal [4]Department of Geology, Faculty of Sciences and Techniques, Université Abdou Moumouni, Niamey, Niger

出　　处：《Open Journal of Geology》2024年第1期50-80,共31页地质学期刊（英文）

摘　　要：A regional study connecting geolelectrical surveys with geology and hydrogeology was carried out in the western part of the Iullemmeden basin, precisely in the Dosso region in Niger. One hundred and four (104) vertical electrical sounds have been realized, among them nineteen representative were thus be used as parametric surveys. The local resistivity values of the geological formations of Quaternary range from 100 Ω⋅m to 1000 Ω⋅m (sands and lateritic sandstones). The Oligo-Miocene formation of the Continental terminal (Ct) shows resistivity values ranging from 1 to 5 Ω⋅m (brackish groundwaters) to 1500 Ω⋅m (clay sandstones) while the Upper Cretaceous formation of the Continental “hamadien” (Ch) indicates values ranging from 20 Ω⋅m (sandy clay) to 5000 Ω⋅m (clayey sandstones). The geological formations of Paleocene have values from 2 Ω⋅m (marls) to 60 Ω⋅m (calcareous marl), while the Precambrian basement exhibits values of granite around 300 Ω⋅m to 60,000 Ω⋅m. The update of the structural settings reveals many faults in the study area which explain both the shape of the basin and the geometry of the aquifers. Tectonics is also consistent with the hydraulic characteristics of aquifers. In addition, brackish groundwaters were identified as perched aquifer groundwaters in different depths in Dosso region. They probably come from the marine brines during the regression of the Paleocene Sea.A regional study connecting geolelectrical surveys with geology and hydrogeology was carried out in the western part of the Iullemmeden basin, precisely in the Dosso region in Niger. One hundred and four (104) vertical electrical sounds have been realized, among them nineteen representative were thus be used as parametric surveys. The local resistivity values of the geological formations of Quaternary range from 100 Ω⋅m to 1000 Ω⋅m (sands and lateritic sandstones). The Oligo-Miocene formation of the Continental terminal (Ct) shows resistivity values ranging from 1 to 5 Ω⋅m (brackish groundwaters) to 1500 Ω⋅m (clay sandstones) while the Upper Cretaceous formation of the Continental “hamadien” (Ch) indicates values ranging from 20 Ω⋅m (sandy clay) to 5000 Ω⋅m (clayey sandstones). The geological formations of Paleocene have values from 2 Ω⋅m (marls) to 60 Ω⋅m (calcareous marl), while the Precambrian basement exhibits values of granite around 300 Ω⋅m to 60,000 Ω⋅m. The update of the structural settings reveals many faults in the study area which explain both the shape of the basin and the geometry of the aquifers. Tectonics is also consistent with the hydraulic characteristics of aquifers. In addition, brackish groundwaters were identified as perched aquifer groundwaters in different depths in Dosso region. They probably come from the marine brines during the regression of the Paleocene Sea.

关 键 词：Vertical Electrical Soundings Continental Terminal Continental “Hamadien” Brackish Groundwaters Iullemmeden Basin Dosso Region 

分 类 号：P64[天文地球—地质矿产勘探]