Abstract
The Lingtong granitoid complex (LGC) is composed of four major plutonic units that intruded and cooled in the Middle Jurassic (170-155 Ma). Gravity-anomaly modeling indicates that the LGC is a sheet-like laccolith, less than 10 km thick, that dips shallowly below the surface toward the Tancheng-Lujiang (Tan-Lu) fault, a major lithospheric structure in Eastern China. Measurements of foliation in the field and measurements of planar and linear magnetic fabrics from the study of anisotropy of magnetic susceptibility in the LGC indicate that foliation is dominantly shallowly dipping and magnetic lineation is mainly parallel to the dip direction of the laccolith toward the Tan-Lu fault zone. The trend of lineations is consistent with flow of magma up the thrust to reach shallower levels. The magma of the LGC probably originated by crustal melting within the Tan-Lu fault zone and the emplacement of magma occurred along a shallowly-dipping thrust that drained the Tan-Lu fault zone, the mechanism of which is mainly dike-fed model.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 535-544 |
| Number of pages | 10 |
| Journal | Science in China, Series D: Earth Sciences |
| Volume | 44 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 2001 |
Bibliographical note
Funding Information:Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant No. 49772149), NFS of the United States (NFS/INT-9507687) and Doctoral Foundation of Ministry of Education of China (1996—1998). We thank Dr. Michael Jackson (Minnesota) and Senior Engineer Mr. Hou Guoliang for their kind help and teaching in using the magnetic susceptibility anisotropy bridge, and we also thank Associate Professor Zhang Changhou for his help during field work.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
Keywords
- 3D-geometry
- Anistropy of magnetic susceptibility
- Emplacement mechanism
- Granitoid pluton
- Gravity modeling