摘要
位于中朝准地台的华北地区是由几个不同的断块组成的,重力异常场的分布具有很强的浅部效应、块状分布和深浅叠加场的特点。重力的高程效应很复杂,不同波长的起伏变化有不同的影响系数。本文对布格改正的有关问题进行了讨论,指出华北如区表浅层的密度值偏低(2520kg/m^3),该区合理的布格改正公式为△g_2=-0.0879H。将重(?)场的垂直导数和向上延拓结合起来,有利于揭示地壳上部构造特征。本文搜集整理了由第四系到寒武系的沉积层资料,给出了沉积层总厚度和视密度的分布。对深部重力异常的分析表明,华北沉积层的形成有深源性质,在均衡调节中起着一定的内载荷作用。
North China located at the Sino-Korean Paraplaiform is composed of several different blocks. The distribution of the gravity field is characterized by the shallow structural effects, block distribution and stacked field of deep-shallow structure. The gravitational effects of elevation is very complicated and the relieves of topography with different waveleng ths have different gravitational effects. Some relevant problems of Bouguer correction is studied in the paper. The near-surface density North China is quite low of 2520 kg/m3 and thus a reasonable equation of Bouguer correction is deduced, △g2 = - 0.0879H. The combination of vertical derivatives and upward continuation of gravity field is efficient to display the features of shallow structure. The data of sedimentary layers from the Quaternary down to the Cambrian are collected, and then the distributions of total thickness and apparent density of sedimentary deposits are presented. Deep gravitational anomaly indicates that sedimentary structure plays a role of internal loads in compensation adjustment, and its formation is a deep process.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第4期385-398,共14页
Chinese Journal of Geophysics
关键词
重力场
沉积层构造
华北
重力异常
Gravitational anomaly, Sedimentary structure, Bonguer correction, Thickness and density, North China.
