Search for Hualien No.1 and a Study on the Recognition of Shipwrecks Using Sonar Imaging

本研究以聲學理論為基礎，透過聲納影像辨識去定義沉沒在臺灣北部草里外海的沉船是否為花蓮一號。本研究先後使用多音束測深儀及側掃聲納系統進行水下探測，確認目標船位置後，再輔以拖曳式水下攝影機進行光學驗證。分析相關資料後，由目標船船樓及艏甲板的長度比例，艏甲板前桅桿及拱型吊架位置、船樓甲板邊的扶手欄杆、船艙層數、駕駛臺及艉甲板空間尺寸等形貌特徵，認為目標船與花蓮一號的形貌相符，接著再以分離的船艏位置及殘骸形貌，分析推測花蓮一號在沉沒時的下沉過程。本研究在光學認證調查上是失敗的，建議未來研究在有限資源下如欲成功證實本沉船為花蓮一號，可採樣海床物質是否含有載砂船殘留之相關沉積物。This study, based on acoustic theory, analyzed sonar images to detect the shipwrecks sank on the seafloor off northeast Taiwan, to exam if it is Hualien No.1. Multi-beam sonar is used to collect bathymetric information as well as side scan sonar for inspecting the feature. After determine the position of shipwreck, underwater camera was then operated for optics verification. Judging from the length ratio of foredeck and superstructure, the position of foremast, the scene of handrails around reardeck and holds and hanks, the size of bridge and upper deck, we suggested this shipwreck corresponding to Hualien No.1. By analyzing the position of stem and the figure of the ruins of ship, we can assume the sinking process of Hualien No.1. Using underwater camera to make video for optics verification in this study is unsuccessful. Further study is recommended in the future including sediment cores collected around target zone to manifest if there is any sand doesn’t belong to the seafloor but the sand carried by Hualien No.1