沙漠边缘地带旁折光影响的规律

THE LAW OF SIDE-REFRACTION EFFECT INDESERT EDGES

本文根据我国西北地区，塔里木和柴达木两盆地沙漠地区所布设的一等三角锁环资料统计分析结果，得出沙漠地区旁折光属于同性折光场影响，它使得沿沙漠地区布设的一等三角锁系全向沙漠中心偏转。沙漠地区旁折光对三角锁系的方位角条件及基线条件常数项的影响，表现为系统性误差，而一等三角锁系的图形条件和极条件常数项则不受旁折光的影响。按照统计分析检验结果，三角形闭合差仍为随机误差并服从正态分布，而三角锁系的观测误差却不服从正态分布。

: According to the statistic analysis of the data of 1st-order triangulation chains laid along the desert edges of Tarim and Qaidam basins side-refraction in desert forms ho mogeneous refraction field which causes 1st-order tnangulation chains laid along desert edges to deflect towards the desert center The effect of side-refraction in desert on the absolute terms of azimuth and baseline conditions exhibits systematic errors but the ab solute terms of figure and polar conditions are free of the effect According to the test results of statistic distribution triangle closures are random errors in nature they obey normal distribution However observation errors of triangulation chains fail to obey this distribution The argument of this paper is meaningful for the layout observation and adjust ment as Well as improving the accuracy of triangulation chains laid along desert edges