The North China Craton (NCC) is one of the oldest cratons in the world. Currently, the destruction mechanism and geodynamics of the NCC remain controversial. All of the proposed views regarding the issues involve studying the internal density structure of the NCC lithosphere. Gravity field data are among the most important data in regard to investigating the lithospheric density structure, and gravity gradient data and gravity data each possess their own advantages. Given the different observational plane heights between the on-orbit GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) satellite gravity gradient and terrestrial gravity and the effects of the initial density model on the inversion results, sequential inversion of the gravity gradient and gravity are divided into two integrated processes. By using the preconditioned conjugate gradient (PCG) inversion algorithm, the density data are calculated using the preprocessed corrected gravity anomaly data. Then, the newly obtained high-resolution density data are used as the initial density model, which can serve as constraints for the subsequent gravity gradient inversion. Several essential corrections are applied to the four gravity gradient tensors (T_xx, T_xz, T_yy, T_zz) of the GOCE satellite, after which the corrected gravity gradient anomalies (${{\mathit{T}}^{′}}_{xx}$, ${{\mathit{T}}^{′}}_{xz}$, ${{\mathit{T}}^{′}}_{yy}$, ${{\mathit{T}}^{′}}_{zz}$) are used as observations. The lithospheric density distribution result within the depth range of 0–180 km in the NCC is obtained. This study clearly illustrates that GOCE data are helpful in understanding the geological settings and tectonic structures in the NCC with regional scale. The inversion results show that in the crust the eastern NCC is affected by lithospheric thinning with obvious local features. In the mantle, the presented obvious negative-density areas are mainly affected by the high-heat-flux environment. In the eastern NCC, the density anomaly in the Bohai Bay area is mostly attributed to the extension of the Tancheng–Lujiang major fault at the eastern boundary. In the western NCC, the crustal density anomaly distribution of the Qilian block is consistent with the northwest–southeast strike of the surface fault belt, whereas such an anomaly distribution experiences a clockwise rotation to a nearly north–south direction upon entering the mantle.

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华北克拉通岩石圈密度结构GOCE卫星重力梯度数据和地面重力数据的顺序反演

华北克拉通（NCC）是世界上最古老的克拉通之一。目前，NCC的破坏机制和地球动力学仍存在争议。关于该问题的所有提议观点都涉及研究NCC岩石圈的内部密度结构。重力场数据是研究岩石圈密度结构最重要的数据之一，重力梯度数据和重力数据各有其优势。考虑到在轨GOCE（重力场和稳态海洋环流探测器）卫星重力梯度和地面重力之间的观测平面高度不同，以及初始密度模型对反演结果的影响，重力梯度和重力的顺序反演分为两个集成过程。通过使用预处理的共轭梯度（PCG）反演算法，可以使用预处理的校正重力异常数据来计算密度数据。然后，将新获得的高分辨率密度数据用作初始密度模型，该模型可以用作后续重力梯度反演的约束条件。对四个重力梯度张量（GOCE卫星的T _{x x}， T _{x z}， T _{y y}， T _{z z}），之后校正后的重力梯度异常（${{\mathit{Ť}}^{′}}_{XX}$， ${{\mathit{Ť}}^{′}}_{Xž}$， ${{\mathit{Ť}}^{′}}_{ÿÿ}$， ${{\mathit{Ť}}^{′}}_{žž}$）用作观察值。获得了NCC中0〜180°km深度范围内的岩石圈密度分布结果。这项研究清楚地表明，GOCE数据有助于了解区域范围内NCC的地质环境和构造结构。反演结果表明，东部地壳NCC受到岩石圈变薄的影响，局部特征明显。在地幔中，出现的明显的负密度区域主要受到高热通量环境的影响。在东部华北地区，渤海湾地区的密度异常主要归因于东部边界的cheng城—庐江大断裂的扩展。在NCC西部，祁连区块的地壳密度异常分布与表面断层带的西北向东南走向一致，