建構與評估跨孔熱示蹤劑試驗模式解析現地尺度含水層流場特性

多數的水文地質調查工作都是為了能夠清楚地描繪出含水層參數在空間上的分布特性，含水層抽水試驗為最直接獲得水文地質參數之方法，然傳統之水力試驗僅能求得單一或相對含水層特徵參數之平均值，並無法妥善解析平面空間上之參數分布。水力剖面掃描方法的提出有效提升空間資料取得的困境，可同時獲得每口井之流通係數值外，並可經由各口井間洩降關係求得儲蓄係數或比儲係數。水力剖面掃描法雖可有效解析出含水層特徵參數之空間分布狀態，但其試驗設計困難以及分析方法繁瑣且複雜，針對於具有需要短促工作期限需要馬上取得水文地質參數之相關工作，反而較難廣泛執行於實際應用層面。因此本研究提出熱示蹤劑法之概念，以地下水溫度作為監測指標參數，當藉由井內釋放人工熱源，由注熱點所釋放出之熱能即可視為「溶質」隨地下水傳輸，由熱作溶質於地下水中釋放可尋找地下水傳輸之優勢路徑，藉由注熱井及觀測井溫度梯度差異之變化定義地下水於含水層中之流向與流速，並以解析解反推估定義含水層特徵參數與空間分布場。

關鍵字

熱示蹤劑；水力傳導係數；溫度觀測

並列摘要

Understanding the hydrogeological conditions and aquifer parameters such as transmissivity and hydraulic conductivity of the site plays an imperative role in groundwater resource management, engineering design, and aquifer remediation. This study aims to assess aquifer heterogeneity using multiple hydraulic tests in the same well field. The approach compares estimations by adopting diverse data analysis methods, thereby providing insights into the use of hydraulic surveys at the field-scale site. Single well, multi-well, and cross-hole constant rate pumping tests were conducted in the well field. The well field included five wells that were considered for pumping and slug tests. On the other hand, the heat carried by groundwater served as a tracer to estimate the direction and velocity of groundwater flow at the site. A heater was used to elevate the temperature of different wells to generate an anomalous signal. These temperature anomalies were used to estimate the thermal and hydraulic conductivities using an inversion analysis solution. The results of the hydraulic tests were compared with heat tracer tests. This study provides a more efficient approach for obtaining the spatial distribution of aquifer parameters; and helps project management make better decision under same budget.

並列關鍵字

heat transfer ； hydraulic conductivity ； temperature observation

參考文獻

王新建、朱大林、潘紀順 (2015)，利用溫度全局優化法探測堤壩多重集中滲漏，工程地質學報，第23 卷第 2 期，345-343頁。doi:10.13544/j.cnki.jeg.2015.02.019。

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Bohling, G.C., Zhan, X., Butler J.J., Jr., Zheng, L., (2002) Steady shape analysis of tomographic pumping tests for characterization of aquifer heterogeneities. Water Resources Research, 38, 60-1-60-15. doi:10.1029/2001WR001176。

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