| A layer of the hydrosphere. |
| •owl:Thing |
| •SpatioTemporalThing |
| •Endurant |
| •PhysicalEndurant |
| •PhysicalObject |
| •NonAgentivePhysicalObject |
| •PhysicalPlace |
| •GeosphereLayer |
| •HydrosphereLayer |
| •PlanetaryStructureObject |
| •HydrosphereLayer |
| PlanetaryStructureObject |
| GeosphereLayer |
| hasPrimarySubstanceConstituent SOME Water |
| isPartOf SOME Hydrosphere |