Fractures: Tension and Shear

Abstract

Abstract The paper applies the observation cycle to rock fracturing processes. Specifically, it repeats the observation cycle by going from the large (field) scale to increasingly detailed laboratory scales. With this, it is possible to determine that what appear to be tensile or shear fractures on the large scale are produced through a combination of tensile and shear mechanisms on the smaller scale. This involves observations with a variety of techniques that are briefly described. What is also emphasized is that observation has to go hand in hand with abstraction, i.e., modeling to help understand the observed phenomena. The paper, therefore, makes two contributions—a better understanding of rock fracturing processes and showing the importance of the observation cycle in a scientific process.