Lithospheric structure and evolution of the North China Craton: An integrated study of geophysical and xenolith data
- PDF / 8,285,426 Bytes
- 15 Pages / 595.276 x 793.701 pts Page_size
- 65 Downloads / 192 Views
thospheric structure and evolution of the North China Craton: An integrated study of geophysical and xenolith data 1*
1,2
1
1
Jianping ZHENG , Bing XIA , Hongkun DAI & Qiang MA 1
2
School of Earth Sciences, State Key Laboratory of Geological Processes and Mineral Resources,
China University of Geosciences, Wuhan 430074, China; State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
Received March 16, 2020; revised September 15, 2020; accepted September 24, 2020; published online November 10, 2020
Abstract Determination of the physical and chemical structures of the inaccessible continental lithosphere by comprehensive geophysical and geochemical studies can provide valuable information on its formation and evolution. Extensive studies from various disciplines have revealed complex lithospheric modification of the North China Craton (NCC), but less attention has been paid to an integrated study from different fields. Here we provide an integrated constraint on the lithospheric mantle structure of the NCC by comprehensive semiology, gravity and thermal studies with xenolith data involving depth (levels in the lithosphere), property (chemical and physical), and timing (formation and reworking ages). Our results suggest that the NCC has a relatively heterogeneous lithospheric mantle. Its margins and internal weak zones, especially in the eastern NCC, are generally underlain by the fertile, weakly metasomatized mantle with generally young formation ages. In contrast, its core tends to preserve the refractory, strongly metasomatized mantle with ages roughly coupled to the overlying Archean crust. Such a lithospheric structure shows the preferential modification of the lithospheric mantle in the eastern NCC and in the peripheral regions of the western NCC. The interior of the craton, especially most of the western NCC, remains stable and has been weakly modified. Keywords Craton Citation:
Lithospheric thermal and density structure, Peridotite xenolith, Heterogeneous mantle replacement, North China
Zheng J, Xia B, Dai H, Ma Q. 2020. Lithospheric structure and evolution of the North China Craton: An integrated study of geophysical and xenolith data. Science China Earth Sciences, 63, https://doi.org/10.1007/s11430-020-9682-5
1. Introduction The lithosphere, including the crust and uppermost rigid mantle, is the outer shell of Earth. Knowledge on the structure, composition and evolution of the lithosphere is crucial for understanding the essential problems of Earth sciences, such as the continental formation and plate tectonics (Griffin et al., 1999; Lee et al., 2011). Integration of geochemical methods with the multiplicity of geophysical results provides an opportunity to understand the lithosphere structure (Artemieva, 2011; Eaton et al., 2009). For instance, the thermal * Corresponding author (email: [email protected])
structure of lithosphere can be constrained by combined thermal and xenolith studies. The former generally uses th
Data Loading...
