基于直升机航空重力同步地形的布格改正处理

Airborne Bouguer gravity based on synchronous terrains surveyed using helicopter airborne gravimetry

重点勘探区内大规模的采矿活动从未间断过,矿山采空区、排土场和尾矿库等处在不断形变过程中。仍依靠搜集数字地形的方式,无法做到地形数据与航空重力测量数据的良好匹配,给航空重力地形改正和中间层改正带来极大的改正误差。本文通过直升机重磁测量系统的飞行GNSS大地高与无线电离地高度进行求差,再转换到正常高,最后经过调平和精细化处理获得同步实测地形。又与搜集的多种地形数据一起对比ICESat-2/ATL08星载激光高程,实测地形Wxd100和Wxd400的高程精度分别为5.33 m和8.93 m。使用实测地形进行航空重力布格改正后,矿区和多条典型测线的数据质量有了明显改善。

Large-scale mining activities have been continued in key exploration areas.Consequently,the mined-out areas,waste dumps,and tailings ponds of mines are constantly deforming.As a result,the digital terrain method fails to make the terrain data closely match the airborne gravimetric data,leading to serious correction errors in airborne gravity terrain correction and stone-slab correction.This study calculated the difference between the GNSS geodetic height and the radio terrain clearance altitude of the helicopter gravity and magnetic survey system and then converted the GNSS geodetic height into normal height.Then,the synchronous surveyed terrains were obtained through leveling and fine-scale processing.Moreover,the surveyed terrain data,together with various collected terrain data,were compared with the ICESat-2/ATL08 spaceborne laser elevation.The results show that the surveyed terrains Wxd100 and Wxd400 had elevation precision of 5.33 m and 8.93 m,respectively.After airborne Bouguer gravity correction was conducted using the surveyed terrains,the data quality of the mining area and several typical survey lines was greatly improved.