我国采用的高程系统是正常高高程系统,其高程起算面是似大地水准面。水准测量的最终高差是按式: H_常~B—H_常~A=H_测~B—H_测~A+ε+λ计算式中:ε——正常水准面不平行改正。λ——重力异常改正。在一般水准平差计算工作中,往往不考虑重力异常的影响。这种作法,当测线布设在平原或高差不大的丘陵区的情况下是可以的,但测线是布设在海拨高,高差大的山区时,就值 The elevation system used in our country is a normal high-elevation system, and its elevation is similar to the geoid. The final height difference of leveling is calculated according to the formula: H_normal ~ B_H_normal ~ A = H_test ~ B_H_test ~ A + ε + λ In the formula: ε - normal leveling non-parallel correction . λ - gravity anomaly correction. In the calculation of the general level adjustment, often do not consider the impact of gravity anomalies. This practice, when the survey line layout in the plain or small hilly area is not the case, but the survey line is located in the high altitude, high mountain range, the value