Study on aquifer hydraulic properties using tidal response method for future groundwater development
Study on aquifer hydraulic properties using tidal response method for future groundwater development
复制标题
利用潮汐响应法研究含水层水力特性，为未来地下水开发提供依据
DOI：
10.1007/s10333-019-00749-8
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发表时间：
2019
影响因子：
2.2
通讯作者：
Satoshi Ishida
中科院分区：
文献类型：
--
作者：
Katsushi Shirahata;Shuhei Yoshimoto;Takeo Tsuchihara;Satoshi Ishida
采用潮汐响应法对某岛屿含水层的水力特性进行了研究。地下水是研究岛的主要水资源，未来地下水开发的含水层调查正在进行中。该方法由三个部分组成：在受同一海潮影响的成对近岸和相对内陆地点观测地下水水位，对收集到的地下水时间序列进行分解以产生孤立的潮汐分量，并应用描述地下水水位振荡在含水层中传播的基本公式来确定水力参数。这些观测只需要如今常用的自动记录地下水位的仪器。采用了两种分解技术，仅使用电子表格软件的内置功能即可轻松实现。在分离潮汐成分之前，使用数字高通滤波将半日和日周期的潮汐成分从较长周期的潮汐成分中分离出来。傅里叶变换的基本公式用于分离具有特定周期的潮汐成分。孤立一个潮汐成分有助于减少基于地下水水位正弦振荡幅度衰减和相移的水力参数计算公式的误差。含水层水力参数的计算也可以直接在电子表格上完成。推导出的含水层水力参数与之前在同一岛屿上进行的泵送试验的结果相比较。这些结果现在被用作进一步调查岛上可持续地下水开发的基础。
The hydraulic properties of an island’s aquifers were studied using a tidal response method. Groundwater is the principal water resource on the studied island, and the investigations of the aquifer for future groundwater development are ongoing. The method consists of three parts: observations of groundwater levels at paired near-shore and relatively inland sites affected by the same ocean tide, decompositions of the collected groundwater time series to yield isolated tidal components, and application of basic formulas describing propagation of groundwater-level oscillations in aquifers for determining hydraulic parameters. The observations require only auto-logging groundwater-level meters that are commonly used these days. Employed were two decomposition techniques that are easy to implement using only the built-in functions of spreadsheet software. Digital high-pass filtering was used to separate the tidal components of semidiurnal and diurnal periods from longer-period components prior to the following isolation of tidal constituents. Basic formulas for the Fourier transform were used to isolate one tidal constituent with a specific period. The isolation of one tidal constituent helps to reduce errors in the hydraulic parameter calculations based on formulas using the amplitude attenuation and phase shift of sinusoidal oscillations of the groundwater level. The calculation of aquifer hydraulic parameters can also be done directly on a spreadsheet. The derived aquifer hydraulic parameters compared well with those that were previously reported based on a pumping test conducted on the same island. The results are now used as a basis for further investigation of sustainable groundwater development on the island.