乌江上游深切峡谷区平寨水库伴生的岩溶地下水库库容计算

Reservoir Capacity Calculation of Karst Underground Reservoir Associated with Pingzhai Reservoir in Deep Canyon Area of Upper Reaches of Wujiang River

选取贵州乌江南源上的平寨水库作为研究对象,对其伴生的岩溶地下水库的库容进行计算。平寨水库是贵州省黔中水利枢纽工程的控制性水源工程,总库容达10.89亿m^(3)。该地表水库位于云南高原向黔中高原过渡斜坡带上的深切峡谷区,峡谷两侧碳酸盐岩地层广泛分布,其中的三叠系下统永宁镇组碳酸盐岩地层岩溶化程度较高,为平寨水库伴生的岩溶地下水库的形成提供了重要条件。采用水库运营期水量反算法,对平寨水库大坝竣工后初始蓄水阶段(2015—2016年)进行水均衡计算,结果表明,与平寨水库相伴生的岩溶地下水库的总库容达3.11亿m^(3),约占平寨水库地表总库容的29%。

Taking Pingzhai reservoir on the southern main stream of Wujiang River in Guizhou Province as a case study,storage capacity of its associated karst underground reservoir is calculated.Pingzhai reservoir is a key water source of Hydro-junction project in Central Guizhou Province,with a total storage capacity of 1.089 billion m^(3).The reservoir is located in the deep canyon area on the slope of Yunnan Plateau to Central Guizhou Plateau.The carbonate strata are widely distributed on both sides of the canyon.The carbonate strata of Lower Triassic Yongningzhen Formation have experienced intensive karstification,which is an important foundation for the formation of karst groundwater reservoir in this area.The water balance calculation of the impoundment stage is conducted during the initial operation period of the reservoir(2015-2016).The results show that the storage capacity of the karst underground reservoir accompanying the Pingzhai surface reservoir is 311 million m^(3),accounting for 29%of the total surface capacity of the Pingzhai reservoir.