油層的邊界範圍（或位置）與原始儲油量（Original oil in place, OOIP）有直接關係，而且會影響井底流壓及流率變化。文獻中的研究鮮少探討到地層形貌（如：背斜構造或斷層封閉構造…等）對井底流壓及流率之影響，藉由井底流壓與流率資料以及調查半徑的基礎，推求油層邊界距離與原始儲油量。本研究目的將探討地層邊界及背斜構造對井底流壓與流率影響，並由這些資料分析有限邊界地層之邊界距離。
本研究首先建立水平有限邊界地層模型並設計不同的地層邊界長度，由數值模型產生流壓或流率資料，並與文獻中的解析解進行驗證。驗證成功後，以基本模型為基礎將數值模型進行網格深度上的變化，建立背斜構造數值模式，模擬並計算流壓或流率資料與水平地層進行比較，比較構造對流壓與流率之影響性。在研究中使用交點法與井壓測試分析軟體，分析生產井流壓與流率之資料以進行地層邊界計算。
在地層體積不變的條件下，結果顯示背斜構造的有無對井底流壓與流率影響相當小，對於評估地層邊界距離的影響也相當小。本研究歸納出的結論：（1）水平地層及背斜構造地層對井底流壓與流率的影響，結果顯示地層中構造的有無對井底流壓與流率影響相當小。因此，在均質與均向地層、固定原始儲油量條件下，使用水平地層模型來進行數值模式建立即可；（2）地層邊界對井底流壓與流率的影響，其地層邊界距離評估的結果與實際的地層邊界距離相當接近。在分析流壓資料方面，交點法提供精準度較佳的時間取點方法以評估地層邊界距離；在分析流率資料方面，僅能使用目視法取時間點，對於評估地層邊界距離精準度較低。

An oil reservoir’s area is related to the original oil in place, and wellbore flow-pressure and flow-rate are affected by reservoir boundaries. The literature pays little attention to the effect of the formation structure on wellbore flow-pressure and flow-rate. The boundary effect time of flow-pressure and flow-rate data and radius of investigation are fundamental for understanding the distance from wellbore to boundary and how much original oil there was. We aimed to (1) determine whether reservoir boundaries and formation structure affected wellbore flow-pressure and flow-rate, and (2) estimate the distance from the wellbore to the reservoir boundaries by analyzing the flow-pressure and flow-rate.
We used a flat model of a finite reservoir (with different boundary radii) that simulated bottom-hole flow-pressure in a case of constant production, and flow-rate in a case of constant pressure. The simulation results were validated by analytical solutions from the literature. Based on the validated model, variable depths for each grid and for mapping the anticline structure were part of the structure model. Similarly, the structure model was set up to calculate bottom-hole flow-pressure and flow-rate. The results were compared with the bottom-hole flow-pressure and flow-rate of the structure model with the flat model. We used the intersection method and well-test analysis software to analyze the bottom-hole flow-pressure and flow-rate and to calculate the distance from the wellbore to the reservoir boundary.
Using the same reservoir volume for the flat and structure models, we found that (1) with or without an anticline structure, the result of the structure effect on bottom-hole flow-pressure, flow-rate, and radius of investigation was very slight. Therefore, we could ignore the effect of reservoir structure and use only the flat model as the field model; and that (2) by analyzing the effect of the boundaries on flow-pressure and flow-rate data, and then calculating the boundary radius using the radius-of-investigation equation, the distance from the wellbore to the reservoir boundaries could be determined. The calculated and actual radii of the boundary were close. The accuracy of the radius calculated by analyzing the flow-pressure data using the intersection method was more accurate than using the visual deviation point. Analyzing the flow-rate data using the visual deviation point between the infinite-acting and finite-flow period causes a judgment error and affects the calculated distance from the wellbore to the boundary.

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