| Abbreviation | Definition |
|---|---|
| CGMT | Construction Geotechnical Materials Testing |
| CGRS | Chorological Grid Reference System |
| CGS | Committee on Geological Sciences |
| CGVD | Canadian Geodetic Vertical Datum (orthometric height reference) |
| CIS | Continuous Injection System |
| CISP | Computer Inventory of Survey Plans |
| CLAMS | Coastal Landscape Analysis and Modeling System |
| CLO | Calibrated Lump Ore |
| CM | Core Mantle |
| CMB | Core-Mantle Boundary |
| CMBQ | Central Metasedimentary Belt of Quebec |
| CMT | centroid moment tensor |
| CNMOC | Commander, Naval Meteorology and Oceanography Command |
| CNSZ | Central Nevada Seismic Zone |
| CNYAPG | Central New York Association of Professional Geologists |
| CONT | Center Of Next Transformation |
| COOR | Coordinate |
| COSG | Committee On Seismology and Geodynamics |
| CP | Central Peak |
| CPM | Continuous Permeable Mountain |