海底峽谷之形成起源一直是海底形貌發展中一個開發不完全的領域，而海下異重流與海底峽谷之間的互動是影響峽谷發展很重要的因素。然而現今的研究中對於海底峽谷之起源發展一直沒有一個定論。本研究即是以實驗研究探討異重流下切海底峽谷的機制及其演化過程。研究中以鹽水模擬異重流，並在實驗過程中持續增加地形之地勢差距，讓海底峽谷隨著地勢差距發展自然演化出複雜的集水區與河道。實驗過程中，我們以縮時攝影完整記錄海底峽谷的演化過程，並且使用雷射掃描技術獲得每個發展階段之三維數值高程模型。
我們以正攝影像圖進行地形之幾何平面分析，可以獲得峽谷之集水區面積及其發展形態。而在數值高程模型上，可以量測出峽谷之縱剖面及橫斷面。分析結果顯示將各個階段的縱剖面資料無因次化後，出現了高度的自我相似。我們進一步求得峽谷之沖蝕體積，並提供一個簡化後之幾何關係式，可以推估過去與未來之峽谷演化過程。另一方面，我們以三維數值高程模型為基底，進行流量累積模式分析，定量地獲得異重流於各峽谷中的流量剖面。期待本研究之物理模型實驗及初步之數值模式成果，能對於海底峽谷的起源及其發展過程有進一步的瞭解，也希望引領更多的研究人員投入實驗研究。

Submarine canyon is the main channel to transport material from continental shelf to abyss plan. Interaction between turbidity currents and submarine landscape is important for canyon evolution. But the origin of submarine canyon is not well understood. In this study, we start with an experiment about how the turbidity currents eroded submarine canyon. We substituted turbidity currents with saline flow and gradually increased the relief to evolve both drainage area and channels. The experiment processes are recorded by time-lapse photography. Topographic imaging system is used to construct the DEM for each experiment stage. We use orthophoto for plan-view observation and calculating the area of drainage system. We slice DEMs for longitudinal profiles. The results of normalized longitudinal profiles for each stage shown highly self-similar to each other. We defined the excavated canyon volume and thus derived the simplified geometric equation to estimate canyon volume in the pass and future. We also construct a flow accumulation model through the DEMs to acquire the discharge profile of turbidity currents. Look forward to that our experiment results are not only promoting the studies of canyon evolution, but also inspiring other people to investigate the origin of submarine canyon.

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