巴希拉平原因其农业和采矿活动而成为摩洛哥的重要地区。位于亚干旱至干旱气候,这个平原拥有一个代表碳酸盐序列的含水层系统,磷酸盐,蒸发和冲积沉积物。地下水从Gannour高原(补给区)流向流域充填沉积物以及Zima湖和SedElmejnoun,在那里水蒸发。本研究的目的是表征地下水的化学性质,并评估控制地下水化学的过程。我们可以将水样分为三个水化学水组:补给水(Ca/Mg-HCO3),过渡区水(Ca-HCO3-SO4/Cl)和排放水(Na-Cl/SO4)。因此,水的组成是由易溶矿物如方解石(Ca-HCO3占优势)的可用性决定的,石盐(Na-Cl为主)和石膏(Ca-SO4为主)。Cl/Br比表明Cl浓度因天然岩盐的溶解而增加。当地下水受到极端蒸发的影响时,Cl/Br比可能会增加到1900。高氟化物浓度与低Ca2+浓度(<100mg/L)相关。这意味着当补给水进入含水层时,它开始溶解萤石,因为Ca2+浓度低。一旦地下水被Ca2+饱和,氟化物的固定是通过富氟矿物如氟磷灰石的沉淀而发生的。根据环境同位素(18O和2H)分析,它们是影响地下水的三个潜在过程:1.通过低斜率值验证的蒸发,2.水-岩相互作用,3.水的混合物显示出不同的稳定同位素组成和盐度。
Bahira plain is an important area for Morocco due to its agriculture and mining activities. Situated in a sub-arid to arid climate, this plain hosts an aquifer system that represents sequences of carbonates, phosphates, evaporates and alluvial deposits. Groundwater flows from Ganntour plateau (recharge area) to the basin-fill deposits and Zima Lake and Sed Elmejnoun where water evaporates. The objective of this study was to characterize the chemical properties of the groundwater and to assess the processes controlling the groundwater\'s chemistry. We can divide water samples into three hydrochemical water groups: recharge waters (Ca/Mg-HCO3), transition zone waters (Ca-HCO3-SO4/Cl) and discharge waters (Na-Cl/SO4). Accordingly, compositions of waters are determined by the availability of easily soluble minerals like calcite (Ca-HCO3 dominant), halite (Na-Cl dominant) and gypsum (Ca-SO4 dominant). Cl/Br ratios show that Cl concentration increases from dissolution of natural halite. When groundwater is affected by extreme evaporation Cl/Br ratios may increase up to 1900. High fluoride concentrations are associated with low Ca2+ concentrations (<100mg/L). That means when recharge waters enter the aquifer, it starts dissolving fluorite since the Ca2+ concentration is low. Once groundwater becomes saturated with Ca2+, the immobilization of fluoride is occurring by precipitation of fluoride-rich minerals like fluoro-apatite. According to the environmental isotope (18O and 2H) analyses, they are three potential processes affecting groundwater: 1. Evaporation as verified by low slope value, 2. Water-rock interaction, 3. admixture of waters showed different stable isotope compositions and salinities.