The tide may induce fluctuations in groundwater levels in coastal aquifers.In this paper; a numerical model describing 1D groundwater flow in a coastal confined aquifer was established based on the finite element method.Fluctuation in the tide was simplified as a sinusoidal wave.Groundwater level oscillations in a coastal confined aquifer with sloping initial groundwater level were simulated.A comparison of the results with those of the aquifer with horizontal groundwater level shows that the groundwater level oscillations induced by the tide in the coastal confined aquifer are similar to those of the tide but the fluctuation ranges of groundwater levels are smaller than those of the tide.The degree of the effect by the tide is related to the distance from the coast.The fluctuation range of groundwater levels and the tidal efficiency decrease negatively exponentially with the distance from the coast and are smaller than those of the aquifer with horizontal groundwater level.The time lag of the groundwater levels to the tide increases linearly with the distance from the coast.%海潮波动可以引起海岸带地下水位发生波动.建立了基于有限差分法的滨海地区一维承压含水层地下水运动数值模型.将潮汐波动概化为正弦波,模拟了滨海地区地下水位随潮汐波动的变化.通过与初始水位水平的承压含水层水位变化的比较表明,受海潮影响的滨海承压含水层地下水位与海潮有相似的波动特征,但变幅减小,受海潮的影响程度与离海岸的距离有关,随着离海岸距离的增加,地下水位的变幅及潮汐效率呈负指数函数衰减,但比前者变化程度稍缓,地下水位对海潮的滞后时间随距离呈线性增加.
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