Three-dimensional numerical analysis of magma transport through a pre-existing fracture in the crust

doi:10.1016/j.jog.2014.03.002

	Three-dimensional numerical analysis of magma transport through a pre-existing fracture in the crust
	Chen, Zuan 1; Cheng, Xu 1; Huang, Xiaoge 1; Bai, Wuming 1; Jin, Zhi-He 2
刊名	JOURNAL OF GEODYNAMICS
	2014-05-01
卷号	76 页码:46-55
关键词	Magma transport Pre-existing fracture Finite element method Finite difference method Discontinuous deformation analysis
ISSN号	0264-3707
DOI	10.1016/j.jog.2014.03.002
文献子类	Article
英文摘要	Magmas are transported through pre-existing fractures in many repeatedly erupting volcanoes. The study of this special process of magma transport is fundamentally important to understand the mechanisms and conditions of volcanic eruptions. In this paper, we numerically simulate the magma propagation process through a pre-existing vertical fracture in the crust by using the combined finite difference method (FDM), finite element method (FEM) and discontinuous deformation analysis (DDA) approach. FDM is used to analyze magma flow in the pre-existing fracture, FEM is used to calculate the opening of the fracture during magma intrusion, and DDA is used to deal with the contact of the closed fracture surfaces. Both two-dimensional (2D) and three-dimensional (3D) examples are presented. Parametric studies are carried out to investigate the influence of various physical and geometric parameters on the magma transport in the pre-existing fracture. We have considered magma chamber depth ranging from 7 km to 10 km under the crust surface, magma viscosity ranging from 2 x 10(-2) to 2 x 10(-2) MPa s, and the density difference between the magma and host rock ranging from 300 to 700 kg/m(3). The numerical results indicate that (1) the fluid pressure p varies gradually along the depth, (2) the shape of the magma body during propagation is like a torch bar and its width ranges from 2 m to 4 m approximately in the 3D case and 10 m to 50 m in the 2D case for the same physical parameters used, (3) the crust surface around the pre-existing fracture begins to increase on both sides of the fracture, forms a trough between them, then gradually uplifts during the transport of the magma, and finally takes the shape of a crater when the magma reaches the surface. We have also examined the influence of physical and geometric parameters on the minimum overpressure for magma transport in the 3D case. The numerical results show that our numerical technique presented in this paper is an effective tool for simulating magma transport process through pre-existing fractures in the crust. (C) 2014 Elsevier Ltd. All rights reserved.
WOS关键词	DRIVEN CRACK-PROPAGATION ; DYKE PROPAGATION ; COMPOSITE VOLCANOS ; LOCAL STRESSES ; FILLED CRACKS ; EMPLACEMENT ; BUOYANCY ; DEFORMATION ; MODEL ; EARTHQUAKE
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000335621200004
资助机构	National Natural Science Foundation of China(40874046 ; National Natural Science Foundation of China(40874046 ; Chinese Academy of Sciences(KZCX2-EW-118) ; Chinese Academy of Sciences(KZCX2-EW-118) ; 40974049 ; 40974049 ; 41174073) ; 41174073) ; National Natural Science Foundation of China(40874046 ; National Natural Science Foundation of China(40874046 ; Chinese Academy of Sciences(KZCX2-EW-118) ; Chinese Academy of Sciences(KZCX2-EW-118) ; 40974049 ; 40974049 ; 41174073) ; 41174073) ; National Natural Science Foundation of China(40874046 ; National Natural Science Foundation of China(40874046 ; Chinese Academy of Sciences(KZCX2-EW-118) ; Chinese Academy of Sciences(KZCX2-EW-118) ; 40974049 ; 40974049 ; 41174073) ; 41174073) ; National Natural Science Foundation of China(40874046 ; National Natural Science Foundation of China(40874046 ; Chinese Academy of Sciences(KZCX2-EW-118) ; Chinese Academy of Sciences(KZCX2-EW-118) ; 40974049 ; 40974049 ; 41174073) ; 41174073)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/85241]
专题	中国科学院地质与地球物理研究所
通讯作者	Chen, Zuan
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Study Earths Deep Interior, Beijing 100029, Peoples R China 2.Univ Maine, Dept Mech Engn, Orono, ME 04469 USA
推荐引用方式 GB/T 7714	Chen, Zuan,Cheng, Xu,Huang, Xiaoge,et al. Three-dimensional numerical analysis of magma transport through a pre-existing fracture in the crust[J]. JOURNAL OF GEODYNAMICS,2014,76:46-55.
APA	Chen, Zuan,Cheng, Xu,Huang, Xiaoge,Bai, Wuming,&Jin, Zhi-He.(2014).Three-dimensional numerical analysis of magma transport through a pre-existing fracture in the crust.JOURNAL OF GEODYNAMICS,76,46-55.
MLA	Chen, Zuan,et al."Three-dimensional numerical analysis of magma transport through a pre-existing fracture in the crust".JOURNAL OF GEODYNAMICS 76(2014):46-55.