利用不对称的地下水位潮汐波动确定滨海含水层参数

在滨海地区，地下水水位受潮汐波动影响较大，使得传统的抽水试验、水位回复试验等方法确定含水层参数存在困难且花费较大。通过对广西北海市滨海含水层地下水位动态资料进行分析，发现其上升段和下降段是不对称的。基于海岸带承压含水层正弦潮汐波的传播理论，提出了确定含水层参数的分段法，并与振幅衰减法和滞后时间法进行对比，各种方法求出的储水系数与导水系数之比(S/T)很接近，说明分段法是有效的。对于北海市滨海含水层，上升段求出的S/T值比下降段要大，其成因机理还有待进一步分析。

Determination of Coastal Aquifer Parameters Based on Measurements of Asymmetrical Tidal Fluctuations in Groundwater Levels

Because of the influence of tidal fluctuations, determination of aquifer parameters by using methods of pumping tests and recovery of groundwater levels becomes difficult and costs more in coastal areas. In this paper, through the study of the dynamic data of groundwater levels in the coastal aquifer in Beihai, Guangxi, we find that the rising and falling sections of the tide are asymmetrical. Based on the theory of the propagation of the sinusoidal tidal wave in confined aquifers, we provide a segmentation method to calculate the parameter of the aquifer, and compare the result with the those of the swing attenuation method and the time lag method. The ratios of storativity to transmissivity calculated with the three methods are close. This shows that the segmentation method is effective. The S/T of the rising section is larger than that of the falling section in the coastal aquifer in Beihai. The mechanism needs further analyses.