Age • Along • Array • Below • Caused • Cold • Collide • Cone • Crust • Decreases • Depth • Describe • Distance • Divergent • Diverse • Explore • Form • Forms • Generally • Geological • Giant • Habitats • Hydrothermal • Into • Just • Kilometers • Land • Large • Limestone • Lives • Long • Major • Marine • Mid • Ocean • Reach • Reef • Rift • Shallow • Significant • Sinks • Term • Thousand • Trench • Underwater • Valley • Vary • Vents • Volcanoes • Warm