摘要
利用重力异常构建壳幔密度结构,是获取地球内部物性参数、岩石结构的方法之一,可以为研究地球动力学演化过程提供约束.直接观测到的重力异常是获取壳幔密度结构的重要资料.重力异常是不同深度物质产生的重力场的叠加,针对不同的研究区域,需要对重力异常进行必要的分离;在此基础上,可以通过正演拟合和反演方法等途径获得壳幔密度结构.正演拟合可以获得精细壳幔密度结构,但需要较强的先验约束信息,受主观人为的因素影响较大.反演方法计算快,人为因素影响较小,但获得壳幔密度结构具有平滑的特征,难以得到精细密度结构.反演结果对初始模型有一定的依赖性,非唯一性较强.
As one of the methods to understand the structure and physical properties of earth, constructing crust-mantle density structure using gravity anomalies can provide constraints for geodynamic evolution. Observed gravity anomalies are significant data in obtaining crust-mantle density structure. The anomaly contains anomalies caused by material from different depth. It should be separated for a particular study object. After separation,density structure can be obtained by forward fitting or inversion.Forward fitting can provide detailed crust-mantle density structure,but it needs prior information and it is largely affected by subjective factors. Inversion calculates fast and subjective factors have little influence on it, but it has difficulty in constructing detailed structure and the crust-mantle density structure obtained by inversion is a smooth model. Result of inversion depends on the starting model and it has ambiguity.
出处
《地球物理学进展》
CSCD
北大核心
2016年第1期143-151,共9页
Progress in Geophysics
基金
国家自然科学基金(41274090)资助
关键词
重力
壳幔结构
重力异常分离
重力异常计算
正演拟合
反演
gravity
crust-mantle density structure
separating gravity anomalies
calculating gravity anomalies
forward fitting
inversion
