基于辐射井抽水试验的水文地质参数求解

 在新疆台兰河流域冲洪积扇平原修建坎儿井式地下水库，以解决干旱区水资源合理利用分配等问题。为确定该地下水库库区的水文地质参数，本文利用研究区抽水试验资料，采用等效大井法和博尔顿法计算含水层的渗透系数和给水度，并利用MODFLOW软件建立了数值模型，进行参数反演，以验证计算结果的准确性、可靠性。利用等效大井法在已知抽水量和降深的前提下，反求含水层渗透系数；通过博尔顿法的“迟后疏干”效应，采用配线法确定给水度。计算结果表明：对于台兰河流域含水层的水文地质参数的计算，采用等效大井法和博尔顿法计算的结果较符合实际，为今后计算干旱区含水层水文地质参数提供参考依据。

Determination of hydrogeological parameter based on the data of radiation well pumping test

An underground reservoir was built in the alluvial fan plain of the Tailan River basin to solve the rational use of water resources allocation in the arid areas. In order to solve Xinjiang Wensu agriculture irrigation and domestic water questions, the Karez type of underground reservoir has been constructed in the Tailan River basin’s small Ajili- ke ditch. In order to determine the underground water reservoir area’s hydrogeology parameters, this paper discusses the research area’s pumping water test data, using the equivalent of large well and the Bolton method for calculation of the permeability coefficient and specific yield, and by using numerical model establishes Processing Mod flow software, parameter inversion, to verify the accuracy of the calculation results and reliability. Using the equivalent of large well method and under the premise of knowing pumping volume and drawdown depth of groundwater, the permeability coefficient was reversed；Through the Bolton method’s "after late when" effect, the wiring method is used to determine specific yield. The calculation results show that, Firstly, the method of equivalent large can well solve the permeability coefficients, through the experience formula in the known quantity of pumping and drawdown of groundwater of large diameter radiation well, and reverse the permeability coefficient K value, through the numerical simulation of the parameters of the permeability coefficient inversion, the results show that the calculation results is closer to the actual situation, arid hydrogeology parameters for the calculation of wide application value. Secondly, When the Bolton method was used for solving the specific yield, the following issues were considered:  the unconfined aquifer’s drying off through pumping water does not happen instantly and complete instantaneously (the “after late when” effect of aquifer’s drying off). The test material gotten in pumping water late period was used to determine the aquifer’s specific yield based on the wiring method. However, the calculated specific yield has certain limitation, so the determination of arid aquifer’s hydrogeology parameters must be carried out the further study in the future.