北天山流动重力测网场源分辨能力

Field Source Resolution of Mobile Gravity Network in Northern Tianshan

利用球面六面体单元网络模型建立不同分辨率的重力异常扰动模型检测板,基于北天山地区实际地表流动重力测点分布,进行设定场源异常体的等效源反演恢复,进而评估北天山流动重力测网场源分辨能力。结果表明,在假设地下10 km处存在密度差为±1×10^(-3)g/cm^(3)的场源异常体情况下,北天山重力测网具备0.75°×0.75°及以上场源异常体识别能力;测网中大部分地区具备0.5°×0.5°场源异常体识别能力;测点分布较密集的少部分地区具备0.25°×0.25°场源异常体识别能力。最后,综合考虑北天山测网现有网形、地形、交通条件等因素,给出测网最佳优化方案。

We establish the gravity anomaly disturbance checkboard model with different resolutions using the spherical hexahedral element network model,and perform the gravity field modeling experiment based on the terrestrial mobile gravity measurement point distribution in northern Tianshan region.We then evaluate the field source resolution of mobile gravity network in northern Tianshan.The results show that under the assumption of the existence of field source anomaly with density difference of±1×10^(-3)g/cm^(3) at 10 km below the surface,the northern Tianshan gravity network can identify field source anomaly of 0.75°×0.75°.Most areas in gravity network can identify anomaly of 0.5°×0.5°.Some areas with a dense measurement points distribution can identify anomaly of 0.25°×0.25°.Considering the existing network shape,topography,traffic conditions,the best optimization plan of gravity network is given.