BGS Rock Classification Scheme
Mechanically broken rock without primary cohesion - In the Rock Classification Scheme, this class is subdivided into fault-breccia, and fault-gouge, according to the proportion of visible fragments within a finer-grained matrix. The abundance and size of the fragments depends on the original character of the rock and also the rate and duration of movement. The resulting rocks range from coarse breccias with limited disruption of the original rock to fine gouge where the rock is largely reduced to paste. Any cohesion is the result of secondary cementation. Such rocks invariably form at low confining pressures. British Geological Survey Research Report RR/99/02, section 7.1.
| Code | MRPC |
|---|---|
| Description | Mechanically broken rock without primary cohesion - In the Rock Classification Scheme, this class is subdivided into fault-breccia, and fault-gouge, according to the proportion of visible fragments within a finer-grained matrix. The abundance and size of the fragments depends on the original character of the rock and also the rate and duration of movement. The resulting rocks range from coarse breccias with limited disruption of the original rock to fine gouge where the rock is largely reduced to paste. Any cohesion is the result of secondary cementation. Such rocks invariably form at low confining pressures. British Geological Survey Research Report RR/99/02, section 7.1. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Not Available |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/MRPC |
CAVEAT
"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.