Calculation of dike trajectories from volcanic centers
Calculation of dike trajectories from volcanic centers
复制标题
从火山中心计算堤坝轨迹
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
J. Lister
中科院分区：
文献类型：
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作者：
C. Mériaux;J. Lister
[1]通过对区域应力和岩墙应力的力学分析，解释了火山中心或地幔上方岩墙群的模式，其中岩墙的侵位受应力状态的控制和引导。岩脉形态与由震源和区域应力系统引起的主应力轨迹形态的对比通常被用来推断古应力。然而，堤防的轨迹是由堤防诱发应力和源/区域应力系统之间的复杂相互作用决定的。我们基于一种新的边界积分公式进行了数值计算，该公式考察了区域应力、岩浆压力和堤防注入对连续弯曲堤坝周围局部应力状态的同时影响。堤防路径是根据堤防由I型破坏传播的条件计算的。我们的结果表明，区域应力的大小将比以前基于主应力轨迹分析的估计高2-5倍。
[1] Patterns of dike swarms around volcanic centers or above mantle plumes are interpreted by a mechanical analysis of regional and dike-induced stresses, in which dike emplacement is controlled and guided by the stress state. Comparisons of dike patterns with patterns of principal-stress trajectories caused by a source and a regional stress system are commonly used to infer paleostresses. However, dike trajectories are determined by a complex interaction between dike-induced stresses and the source/regional stress system. We present numerical calculations based on a novel boundary-integral formulation, which examines the simultaneous effects of regional stresses, magma pressure, and dike injection on the local stress state around a continuously curving dike. Dike paths are calculated from the condition that dikes propagate by mode I failure. Our results suggest that the magnitude of the regional stresses would be 2–5 times higher than previous estimates based on principal-stress trajectory analysis.