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Title: Simplified equations for lower crustal flow driven by lateral pressure gradients
SUMMARY Evidence from seismology, geology and geodynamic studies suggests that regional-scale lower crustal flow occurs in many tectonic settings. Pressure gradients caused by mantle processes and crustal density heterogeneity can provide driving force for lower crustal flow. Numerically modelling such flow can be computationally expensive. However, by exploiting symmetry in the physical system, it is possible to represent the vertical component of flow in terms of its lateral components, thereby reducing the problem’s spatial dimension by one. Here, we present a mathematical formulation for flow in a viscous channel below an elastic upper plate, which is optimized for solution by common numerical methods. Our formulation drastically reduces the computational load required to simulate lower crustal flow over large areas and long timescales. We apply this model to two example problems, with and without an elastic upper plate, identifying combinations of parameters that are capable of generating measurable geologic uplift.  more » « less
Award ID(s):
1727451
PAR ID:
10232212
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Geophysical Journal International
Volume:
226
Issue:
2
ISSN:
0956-540X
Page Range / eLocation ID:
1036 to 1044
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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