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年度	102	專案性質	實驗性質
專案類別	研究專案	研究主題	調查
申請機構	健行科技大學	申請系所	空間資訊與防災中心
專案主持人	鄭世楠	職等/職稱	教授
專案中文名稱	應用多重電極排列與感應極化法調查砂礫質地層污染之研究
中文關鍵字	環境地球物理；地電阻影像掃瞄法；感應極化法；砂礫石層污染
專案英文名稱	The application of multiple arrary and induced polarization method to investigate the contaminated site.
英文關鍵字	Geophysics survey；Electrical Resistivity Tomography； Induced Polarization
執行金額
執行期間	2012/12/10 至 2013/12/9
計畫中文摘要	近年來國內外工業活動造成之土地污染案例，對國土資源與生活環境形成莫大威 脅。在各類型污染一旦洩漏其移動分佈深受複雜的水文地質變化所影響，其污染流佈與 調查是我們所重視的。近年來，非破壞性地球物理探勘技術已逐漸運用在污染場址之地 下環境調查，搭配較少量的鑽孔資料可獲得〝面與空間〞資訊。目前地球物理最廣泛運 用之污染調查技術為直流電阻法。 本研究目的利用數值模擬與研究場址中常用之電極排列的二維電阻率影像之解析 度與效能。電極排列包括了溫奈-施蘭卜吉、梯度法、雙極排列法、偶極偶極法等五種 以上方法，並搭配感應極化法材料選用，藉此檢驗野外調查的效能(異常物效應值、訊 號雜訊比)與這些排列法排繪影像的能力。並由實場調查進行檢驗，選出 Dipole(偶極) 系列為最佳施測電極排列法。 感應極化法發展出雙電極施測方法，利用最佳不銹鋼棒作為電流極，而最佳電位極 材料為硫酸銅電極，再搭配最佳偶極偶極電極排列法為砂礫質地層中調查高電阻率汙染 物最佳搭配。成功利用 Dipole 系列方法搭配感應極化法在油品汙染場址及含氯物染場 址，將汙染物描繪出來，再利用採水及採土樣成功驗證本研究成果。 根據油品類與含氯場址現場實證調查結果，油品污染與含氯污染皆呈現與背景地質 相對高 chargeability（ms）的現象。實場調查最佳電極間距為 2 公尺以下。應用土壤與 地下水調查最佳電極排列法為偶極梯度法（Dipole-Gradient array）、梯度法（Edge-Gradient array）與溫奈-施蘭卜吉法（Wenner-Shlumberger array）等三種方法，其他電極排列在不 同的待測物搭配使用。 本研究推薦 Edge-Gradient 電極排列法，Edge-Gradient 電極排列法是理想的多波道 記錄的排列法。因最後的選擇則需視 野外場址的情況與目標物而定， Wenner-Schlumberger 排列法具有良好的資料品質，但因本身排列法解析度限制的因素所 致，對於相對高的異常物響應、高的訊號雜信比與低的雜訊幹擾，解析影像無法呈現最 佳狀況，但其擁有最強能量與最佳資料品質。
計畫英文摘要	DC electrical resistivity surveying is a popular geophysical exploration technique because of its simple physical principle and efficient data acquisition. Traditional resistivity measurements are carried out on the earth’s surface with a specified array in order to obtain apparent-resistivity sounding curves, apparent-resistivity profiling data or apparent resistivity pseudosections, all of which qualitatively reflect the vertical or horizontal variations in subsurface resistivity. This technique is widely used in groundwater, civil engineering and environmental investigations. Numerical simulations are used to compare the resolution and efficiency of 2D resistivity imaging surveys for 5 electrode arrays. The arrays analysed include polepole (PP), pole-dipole (PD), half-Wenner (HW), Schlumberger (SC), dipole-dipole (DD), γ -array (GM), multiple and moving gradient array (GD). Some synthetic geological models were used to examine the surveying efficiency (anomaly effects, signal-to-noise ratios) and the imaging capabilities of these arrays. The responses to variations in the data density and noise sensitivities of these electrode configurations were also investigated using robust (L1-norm) inversion and smoothness-constrained least-squares (L2-norm) inversion for the these synthetic models. The results show the following. (i) GM and WN are less contaminated by noise than the other electrode arrays. (ii) The relative anomaly effects for the different arrays vary with the geological models. However, the relatively high anomaly effects of PP, GM and WB surveys do not always give a high-resolution image. PD, DD and GD can yield better resolution images than GM, PP, WN and WB, although they are more susceptible to noise contamination. SC is also a strong candidate but is expected to give more edge effects. Accordingly, the GD, PD, DD and SC arrays are strongly recommended for 2D resistivity imaging, where the final choice will be determined by the expected geology, the purpose of the survey and logistical considerations.