The purpose of this proposal is to develop finite element models to study the effect of pre-existing zones of weakness and variations in gross mechanical properties in the continental lithosphere in controlling the continental breakup process. Two types of two-D models will be used: cross-sectional, plane-strain models to investigate the role of zones of weakness, and thin sheet models to investigate the role of along-strike variations in mechanical properties.. Total tectonic subsidence will be used to estimate the amount of pre-spreading extension of the margins of the Labrador Sea and Central Atlantic basins. Theoretcial studies such as this are important in order to understand a fundamental process in the evolution of the earths crust: how continents break apart.
