  In this paper a composite model for earthquake rupture initiation and
propagation is proposed. The model includes aspects of damage mechanics,
fiber-bundle models, and slider-block models. An array of elements is
introduced in analogy to the fibers of a fiber bundle. Time to failure for each
element is specified from a Poisson distribution. The hazard rate is assumed to
have a power-law dependence on stress. When an element fails it is removed, the
stress on a failed element is redistributed uniformly to a specified number of
neighboring elements in a given range of interaction. Damage is defined to be
the fraction of elements that have failed. Time to failure and modes of rupture
propagation are determined as a function of the hazard-rate exponent and the
range of interaction.
