Table T6. Glossary of structural terms.
| Term | Definition |
|---|---|
| Composite vein | Compositionally and texturally zoned vein containing different mineral assemblages that may or may not represent different generations. |
| Crystal-plastic | Grain-scale plasticity permitted by a deformation mechanism called “dislocation creep” at relatively high temperature. Dislocations are propagated along favored crystallographic planes. |
| Fabric | Relative orientation of parts of a rock mass. Preferred linear orientation of part of a rock is termed linear fabric, preferred planar orientation is termed planar fabric, and lack of a preferred orientation is referred to as random fabric. |
| Fault | Fractures with kinematic evidence for shear displacement across the discontinuity or with an associated cataclasite. |
| Foliation | Any repetitively occurring penetrative planar feature in a rock body. |
| Joint | Fractures where the two sides show no differential displacement (relative to the naked eye or 10× hand lens) and have no filling material. |
| Late magmatic vein | Fracture filled with texturally and/or compositionally distinct mineral products of late magmatic fluids, usually cutting the primary features of the basalts. |
| Shear vein | Obliquely opening veins with minor shear displacement, filled with slickenfibers or overlapping fibers. |
| Texture | Relative size, shape, and spatial interrelationship between grains and internal features of grains in a rock. |
| Vein | Extensional or oblique open fractures filled with epigenic minerals. |
Previous | Close | Next | Top of page