On the Flow and Fracture of Igneous Rocks

Abstract

L The stress-strain relations of some igneous rocks for longitudinal and lateral direction were observed.The curves of the longitudinal strain versus stress were approximately linear up to the moment of rupture, but the strain in the lateral direction showed the abrupt increase in the fracture range.2. It was found that such abrupt increase of the lateial stravin was closely related with the flow.The longitudinal creep during the moderate period was almost recovered by the removal of the load, but in the lateral direction, large amount of residual strain was observed after the removal of the load.3. The empirical formulae of creep for granite were given as follows, S=A0-F Aie-alt+A2e-a2t+Ase-a3t +B log t+Ct, for the longitudinal direction, and S=A+Blog t+Ct, for the lateral direction, respectively.In the former equation, the reciprocals of a1, a2 and as denote the retardation times.The later equation concurs with the formula given by Griggs and others.