Decompression and Fracturing Caused by Magmatically Induced Thermal Stresses

Abstract Studies of host rock deformation around magmatic intrusions usually focus on the development stresses directly related to intrusion process. This is done either by considering an inflating region that represents intruding body, or multiphase deformation. Thermal processes, especially volume changes caused thermal expansion are typically ignored. We show upper crustal magma bodies likely be significant and sufficient create extensive fracture network body brittle yielding. At same time, cooling induces decompression within intrusion, which can promote appearance a volatile phase. Volatile phases inclusion may thus processes control magmatic‐hydrothermal alteration intrusions. suggests play important role in systems. To quantify magnitude intrusions, we present fully compressible 2D visco‐elasto‐plastic thermo‐mechanical numerical model. utilize finite difference staggered grid discretization graphics processing unit based pseudo‐transient solver. First, purely thermo‐elastic solutions, then include effects viscous relaxation plastic The dominant mechanism our models determined self‐consistent manner, taking into account stress, pressure, temperature conditions. Using experimentally flow laws, resulting comparable even exceed confining pressure. alone could result bodies.