Glossary of terms related to stress states in rock masses 69Palaeostress. A previously active in sifu stress state which is no longer in
existence, cf. residual stress which is currently active. Palaeostress can be
inferred from geological structures but cannot be determined by stress
measurement techniques.
Near-field stress. The natural stress state within the vicinity of, and
perturbed by, a heterogeneity (usually caused by engineering activities,
e.g. a tunnel as a low-modulus inclusion).
Far-field stress. The stress state that exists in the region beyond the
near-field, where no significant perturbation due to the heterogeneity
occurs.
Regional stress. The stress state in a relatively large geological domain.
Local stress. The stress state in a small domain-usually with the
dimensions of, or smaller than, an engineered structure.