國家坐標系統是各項測量作業的基礎，而大地基準的選擇及建立更是會直接影響最後的測量成果，進一步的影響各項國家建設、民生工業以及人民的土地財產等權益。板塊運動之中尤其是非線性的板塊運動更是會改變坐標框架中參考站的相對位置，隨著時間的推移進而導致框架的幾何精度下降。而臺灣地處歐亞板塊及菲律賓海板塊的交界處，頻繁的板塊運動會造成地震、火山以及其他的自然災害，且臺灣各個區域也會因為板塊間的非線性運動而往不同的方向旋轉、位移。目前臺灣使用的坐標系統為TWD97 (Taiwan Datum 97 )，是建立於一個固定的線性框架ITRF94(The International Terrestrial Reference Frame 94)下之靜態基準，因此並不能精確的表達臺灣地區複雜的地殼變動情形，臺灣需要進行大地基準的革新以解決坐標框架變形之問題，即是在原有的靜態基準加上速度場與變形模型來改正因地殼運動造成之坐標偏移。本研究利用 2005 年至 2015 年間之臺灣地區連續運行參考站 GPS 觀測資料計算臺灣地區水平速度場情形，並參考日本、紐西蘭等國之速度模型建立方式，以內插、曲面擬合、局部加權回歸散點平滑等方法建立臺灣地區水平速度與變形模型。而臺灣地區參考站坐標解算之水平精度為 2mm-3mm、高程精度為 6mm-10mm，而速度場之年度平均標準差在 N 軸為 3.81mm，E 軸為 5.18mm。水平速度場模型方面以內插法中的線性及三次樣條內插法建立之模型有最好的精度，另外透過變形模型可以有效將地震之同震位移對坐標預測之影響消除，使速度模型之使用年限得以延長。 / National coordinate system is the foundation of surveying engineering, the establishment and the selection of geodetic datum would directly impact the accuracy of final result. Plate motion will cause earthquakes, volcanic eruptions and other natural disasters. Plate motion especially non-linear motion can also change the relationship between stations in the reference frame. Therefore, a rational and reliable reference frame is needed to ensure the Euclidean integrity quality. Taiwan is located along the bounding of the Eurasian and the Philippine plate, and is therefore a region of non-rigid motion and therefore will shift and rotate in different directions due to the changing stress field. Taiwan’s current coordinate system TWD97 is built by a fixed single term linear model ITRF94. It is not able to precisely model the non-linear motion of the crustal in the Taiwan region. Therefore, Taiwan needs velocity and deformation model to correct the distortion which caused by the crustal motion. This study used 11 years of Taiwan CORS GPS data to investigate the horizontal velocity field in Taiwan and established the horizontal velocity and deformation model by curve fitting, interpolation and LOWESS method. The horizontal coordinate accuracy of the stations is about 2mm-3mm, the vertical accuracy is about 6mm-10mm, and the average standard deviation of velocity field is 3.81mm in N axis, 5.18mm in E axis. As for velocity model, linear and cubic spline interpolations have better model accuracy. In addition, the deformation model can effectively eliminate the influence of coseismic deformation, so that the velocity model will not lose its utility.
| Identifer | oai:union.ndltd.org:CHENGCHI/G0104257027 |
| Creators | 熊育賢, Hsiung, Yu Hsien |
| Publisher | 國立政治大學 |
| Source Sets | National Chengchi University Libraries |
| Language | 中文 |
| Detected Language | English |
| Type | text |
| Rights | Copyright © nccu library on behalf of the copyright holders |
Page generated in 0.0024 seconds