Pd. Bons, Development of crystal morphology during unitaxial growth in a progressively widening vein: I. The numerical model, J STRUC GEO, 23(6-7), 2001, pp. 865-872
A two-dimensional numerical model for the simulation of the formation of mi
crostructures in crack-seal veins is presented here. The grain aggregate in
the vein is described by grain boundary nodes that link short, straight bo
undary segments. Growth of crystals into a crack takes place by many small
incremental movements of nodes. The rate of growth depends on the chosen gr
owth morphology of the vein-forming material. Different growth morphologies
can be defined. For every user-defined number of steps, the wall rock is m
oved a user-defined distance and direction, which simulates the opening of
a crack, after which sealing can proceed again. The shape of the crack-surf
ace (e.g. smooth or with ridges) can be set by the user and can be made to
match fracture surfaces found in real rocks. The model is capable of reprod
ucing realistic crack-seal textures and can be used to systematically inves
tigate the role of different parameters on the microstructures of veins. Fi
rst applications of the model are presented in Part II of this paper (this
volume). 2001 Elsevier Science Ltd. All rights reserved.