Abstract

Information relating to rates of deformation, that is strain-rates, is rare, partly because of the problems of determining strain, but mainly because of the difficulties encountered in determining the period during which any specific strain is generated. These practical difficulties are discussed and specific examples are presented of strain-rates involved in geological processes. These include slow strain-rates, relating to down warp and uplift, and fast strain-rates associated with meteoritic impact, volcanic activity and faulting. There follows a discussion of strain-rate associated with intrusive events and the rates of deformation which may obtain during folding are inferred from model data.