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Title: Numerical simulations of the mingling caused by a magma intruding a resident mush
Currently, our ability to interpret the mechanics of magma mingling and mixing is limited by an incomplete understanding of the modes of mixing across all melt fractions and compositions. Here, we present numerical simulations of the emplace- ment of crystal-free magma in crystal-rich reservoirs employing a computational fluid dynamics and discrete element method (CFD–DEM). We performed two runs corresponding to the emplacement of basalt into two end-member types of magmas mush (basaltic and dacitic). We found that the intruded volumes have similar shapes and are surrounded by a halo where the crys- tal volume fraction of the mush is lower. The dynamics of intruded melt are, however, different. Importantly, the mingling of the intruded and host materials starts after emplacement and consists in the incorporation of mush material into the intruded magma. Our findings imply that purely thermo-mechanical processes controlled by grain-scale dynamics are sufficient to explain fundamental aspects of recharge.  more » « less
Award ID(s):
1950113
PAR ID:
10555675
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Volcanica
Edition / Version:
1
Volume:
7
Issue:
1
ISSN:
2610-3540
Page Range / eLocation ID:
89 to 104
Subject(s) / Keyword(s):
magma
Format(s):
Medium: X Size: 2MB Other: pdf
Size(s):
2MB
Sponsoring Org:
National Science Foundation
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