Pete Oxford / Geothermal activity as evidenced by bubbles eminating from the seabed, Roca Redonda and eroded volcano in mid ocean north of Isabela Island, Galapagos Islands, Ecuador, South America

Doug Perrine / Hot molten pillow lava erupts from an underwater lava tube at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii

Tui De Roy / Cerro Azul caldera with lake and tufa cone at 5,900 feet, Cerro Azul Volcano, Isabella Island, Galapagos Islands, Ecuador

Doug Perrine / Shimmering heat waves distort the image of diver as he samples erupting pillow lava at ocean entry of Kilauea Volcano, Hawaii Island.

Doug Perrine / Videographer filming pillow lava erupting underwater at Kilauea Volcano, Hawaii.

Doug Perrine / Diver shaping erupting pillow lava by hand to form underwater lava sculptures at ocean entry from Kilauea Volcano, Hawaii.

Doug Perrine / Diver sampling red hot pillow lava at underwater eruption of Kilauea Volcano, Hawaii.

Michel Roggo / Underwater view of Blue Lake, lake in an extinct volcano, Mount Gambier, South Australia, Australia. March 2015. Photographed for The Freshwater Project

Michel Roggo / Underwater view of Blue Lake, lake in an extinct volcano, Mount Gambier, South Australia, Australia. March 2015. Photographed for The Freshwater Project

Michel Roggo / Underwater view of Blue Lake, lake in an extinct volcano, Mount Gambier, South Australia, Australia. March 2015. Photographed for The Freshwater Project

Franco Banfi / Mesmerising dancing volcanic sands and multicoloured sediments leaping from the bottom at Litlaa 'Little River', northern Iceland

Franco Banfi / Split level view of volcanic crack Nesgja, in Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba diver exploring volcanic crack Nesgja, in Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba diver exploring volcanic crack Nesgja, in Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba diver exploring volcanic crack Nesgja, in Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba diver diving 'Little Strytan' a chimney rising from 25 meters in hot water, emerging from Strytan - the only geothermal cone found in the world shallow enough for scuba diving, Eyjafjordur nearb...

Franco Banfi / Scuba diver in the Silfra Lagoon, with a shallow sandy bottom, visibility stretching to 120m, Thingvellir National Park, Iceland.

Franco Banfi / Diver leaving the cathedral at Silfra Canyon, a deep fault filled with fresh water in the rift valley between the Eurasian and American tectonic plates, Thingvellir National Park, Iceland.

Franco Banfi / Diver explores the cathedral at Silfra Canyon, a deep fault filled with fresh water in the rift valley between the Eurasian and American tectonic plates, Thingvellir National Park, Iceland.

Franco Banfi / Scuba diver runs through Silfra Hall, a 200 meters up and down swim that leads to Silfra Cathedral, Thingvellir National Park, Iceland.

Franco Banfi / Scuba diver coming up after a dive inside the volcanic crack Nesgja, in the Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba diver inside the volcanic crack Nesgja, in the Asbyrgi National Park, northern Iceland

Franco Banfi / Scuba divers getting ready to jump inside the volcanic crack Nesgja, in the Asbyrgi National Park, northern Iceland

Franco Banfi / Mesmerising dancing volcanic sands and multicoloured sediments leaping from the bottom at Litlaa 'Little River', northern Iceland

Pete Oxford / San Lucas Marsupial Frog (Gastrotheca pseustes) tadpole, Chimborazo Volcano, Andes, Ecuador

Doug Perrine / Hot lava from Kilauea Volcano erupting underwater as pillow lava, offshore from Hawaii Volcanoes National Park, Puna, Hawaii,Hawaiian Islands, USA. 20th January 2013.

Doug Perrine / Hot lava from Kilauea Volcano erupting underwater as pillow lava, offshore from Hawaii Volcanoes National Park, Puna, Hawaii,Hawaiian Islands, USA. 20th January 2013.

Norbert Wu / Volcano Sponge (Anoxycalyx joubini) detail, Komodo Island, Indonesia

Doug Perrine / Diver Bud Turpin observes erupting pillow lava at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii. Model released MR 381

Doug Perrine / Videographer Shane Turpin films pillow lava erupting underwater at Kilauea Volcano, Hawaii, MOdel released MR 382

Doug Perrine / Hot molten pillow lava erupts from an underwater lava tub at ocean entry of eruption from Kilauea Volcano, Hawaii, USA

Doug Perrine / Diver Bud Turpin observes erupting pillow lava at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii. Heat waves rising from the lava distort his image Model released MR 381

Doug Perrine / Diver Bud Turpin observes erupting pillow lava at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii, Heat waves rising from the lava distort his image. Model released MR 381

Doug Perrine / Hot molten pillow lava erupts from an underwater lava tube at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii

Doug Perrine / Hot molten pillow lava erupts from an underwater lava tube at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii

Doug Perrine / Diver Bud Turpin observes erupting pillow lava at ocean entry of Kilauea Volcano on Hawaii Island, Hawaii. Heat waves rising from the lava distort his image. Model released MR 381

Doug Perrine / Diver Bud Turpin shapes erupting pillow lava by hand to form underwater lava sculptures at ocean entry from Kilauea Volcano, Hawaii Island, while son Shane Turpin shoots video Model released MR 381,...

Norbert Wu / Volcano Sponge (Anoxycalyx joubini) pair primitive animal colonies that filter water for food particles, Antarctica

Juergen Freund / Diver at bubbling underwater volcano. Indo-pacific ocean.

David Fleetham / Highly acidic hydrogen sulfide (H2S) bubbles emanating out of the sand on the seabed, off the volcanic Apo Island, Philippines, Pacific Ocean.

Doug Perrine / Gray reef shark (Carcharhinus amblyrhynchos) juveniles and Bluestripe snapper (Lutjanus kasmira) swimming through channel formed by collapsed lava tube, Mahaiula, North Kona, Hawaii, USA, Pacific Ocea...

Franco Banfi / Volcano sponge (Anoxycalyx (Scolymastra) joubini) portrait, Antarctic Peninsula, Antarctica, Southern Ocean.

Juergen Freund / Cabbage coral (Scleractinia) in coral reef near Gunung Banda Api volcano, these corals thrived in lava flow from the 1988 eruption. Banda Neira, Banda Islands, Indonesia.

Juergen Freund / Cabbage coral (Scleractinia) in coral reef, diver in background. Cabbage coral thrived in lava flow from the 1988 eruption. Near Gunung Banda Api volcano, Banda Neira, Banda Islands, Indonesia. 2018.

Juergen Freund / Cabbage coral (Scleractinia) in coral reef near Gunung Banda Api volcano, these corals thrived in lava flow from the 1988 eruption, taken with fisheye lens. Banda Neira, Banda Islands, Indonesia.

Juergen Freund / Cabbage coral (Scleractinia) in coral reef near Gunung Banda Api volcano, these corals thrived in lava flow from the 1988 eruption. Diver in background, taken with fisheye lens. Banda Neira, Banda Isl...

Juergen Freund / Cabbage coral (Scleractinia) in coral reef near Gunung Banda Api volcano, these corals thrived in lava flow from the 1988 eruption. Diver in background. Banda Neira, Banda Islands, Indonesia.

Juergen Freund / Coral reef taken with fisheye lens. Near Gunung Banda Api volcano, Banda Neira, Banda Islands, Indonesia.