| Term | Description |
| Vent | |
| IceShelf | |
| VentField | |
| Backarc | |
| DrillHole | |
| VolcanicCone | |
| Hemisphere | |
| Lagoon | |
| Island | |
| FocusSite:MARGINS | Margins Focus Site |
| Rift | |
| Forearc | |
| BackarcBasin | |
| RidgeAxis | |
| Estuary | A partly enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. |
| Shelf | |
| Fault | |
| SubductionZone | A type of convergent plate boundary where two tectonic plates move towards one another and one slides under the other |
| Continent | |
| Lake:Subglacial | |
| Lake | |
| Gulf | |
| ForearcBasin | |
| Atoll | A ring-shaped coral reef including a coral rim that encircles a lagoon partially or completely. The coral of the atoll often sits atop the rim of an extinct seamount or volcano which has eroded or subsided partially beneath the water. |
| Glacier | |
| FocusSite:GeoPRISMS | GeoPRISMS Focus Site |
| Ocean | |
| SpreadingCenter | Tectonic feature |
| Iceberg | |
| Volcano | |
| Margin | |
| RidgeSlope | |
| River | |
| Seamount | |
| TripleJunction | |
| Rise | relatively shallow area of ocean |
| Strait | |
| Bay | |
| FossilRidge | |
| VolcanicArc | |
| Basin | |
| Canyon | |
| TransformFault | |
| Peninsula | |
| VentCluster | A hydrothermal complex with numerous hydrothermal vents. |
| FocusSite:Ridge2000 | Ridge 2000 Focus Site |
| FocusSite:Arctic | Arctic Focus Site |
| SpreadingCenterSegment | |
| Fjord | |
| Sea | |
| Plate | Lithospheric Plate |
| Slope | |
| Ridge | |
| OceanicPlateau | |
| Archipelago | chain, cluster, or group of islands |
| AbyssalHill | |
| FractureZone | |
| MountainRange | |
| Caldera | |
| FocusSite:Antarctic | Antarctic Focus Site |
