青藏高原地壳运动与形变的GPS研究──第1期观测的精密星历解

Study on the Crust Movement & Deformation in QH-XZ Plateau via GPS Observation──the Solution Using Precies Ephemeris for the First term Observation

本项目组于１９９３年７月至８月，对青藏高原的地壳运动进行第１期监测，并用广播星历进行解算．１９９４年秋，又使用经武汉测绘科技大学改进到微机上的美国麻省理工学院研制的ＧＡＭＩＴ精密定位软件和ＮＧＳ（ＮａｔｉｏｎａｌＧｅｏｄｅｔｉｃＳｕｒｖｅｙ）精密星历，重新进行解算．解算结果表明，在４００多公里范围内，观测两个时段平均基线的重复性达到几毫米的高精度，相对精度优于３．１０×１０（－８），与广播星历解相比，基线重复精度提高了５～１２倍．

The study on the Crust Movement and Deformation in QH-XZ plateau yis GPS observation' is a key subject supported by the Fund of National Natural Science. Its purposes are to establish a high-precision GPS network for the investigation of crust movement and deformation in QH-XZ plateau, and to incorporate it with geology and geophysics to study the crust movement and earth-dynamics. The GPS observation of the crust movement in QH-XZ plateau was carried out forthe first time last year. The software TOPAS and GPS broadcast ephemeris were utilized firstly to process the GPS raw data. The precise positioning software GAMIT, which was developed by Massachusettes College of Science and Engineering and improved by Wuhan Technical University of Surveying and Mapping, and NGS precise ephemeris were used to process the same set of data this year, and the results indicate that the accuracies for the repeatability of the baselines, which are up to 480 km. are olny a few millimeters and the relative precision of the baseline is better than 3. 1 × 10(-8).The accuracies obtained by using GPS precise ephemeris are about 5 to 13 times better than using GPS broadcast ephemeris.