Lava Behaving in Ways Nobody Understands

Lava is already one of the most dramatic things on Earth, but sometimes lava does things that go beyond dramatic and into genuinely bizarre. It blows bubbles, it turns blue, it flows like water, and it cools into shapes that look totally strange. So in this video, I'm going to count down 15 strange lava anomalies. Let's start with number 15. Lava bubbles. When most people picture a volcanic eruption, they imagine rivers of this orange molten rock pouring down a mountain. What they probably don't imagine, though, are bubbles. These enormous, glowing, dome-shaped bubbles of lava, inflating from the surface of a lava lake, like something out of a slow-motion cooking show. They can stretch upwards to the size of a car or even a small house before bursting in an explosion of molten droplets and volcanic gas. This is one of the most mesmerizing things you can witness on an active volcano. Lava bubbles form when trapped volcanic gas, primarily carbon dioxide and sulfur dioxide, rise up through the magma column and collect just beneath the surface of a lava lake. The gas pushes the semi-molten skin of the lava upward, stretching into a thin dome that glows bright orange from the heat of the liquid rock. The dome expands, sometimes reaching about 15 or 20 feet across until the pressure exceeds the strength of the cooling surface skin, and the bubble pops, collapsing back into the lava in a spray of incandescent fragments that arc high through the air. Some of the best places to see these lava bubbles are at persistent lakes. Erta Ale in Ethiopia, Nyiragongo at the Democratic Republic of Congo, and Kilauea in Hawaii all have produced spectacular bubble activity. These bubbles aren't just cool-looking, they are scientifically useful, too, because the frequency, size, and behavior of them tell volcanologists how much gas is dissolved in the magma. Which is one of the key indicators of whether an eruption is likely to escalate or calm down. But honestly, most people are not watching lava bubble videos for the science. They're watching because a glowing dome of liquid rock the size of a garden shed is inflating and exploding in slow motion. It's one of the most hypnotic things on the internet. Number 14. Pele's Hair and Pele's Tears When lava fountains erupt from Hawaiian volcanoes, the spray of molten rock sometimes catches the wind and stretches into impossibly thin strands of volcanic glass. These translucent fibers is fine as human hair, floating on the breeze and settling across the land for miles downwind. These strands are called Pele's hair, named after the Hawaiian goddess of volcanoes and fire, and they're one of the strangest but most beautiful byproducts of volcanic activity. Each strand of Pele's hair is essentially a tiny thread of basaltic glass, formed when a droplet of molten lava is flung into the air by a fountain or spattering event and the wind stretches it into a filament. The fibers can be less than half a millimeter thick, but several feet long. They're delicate, golden, slightly curved, and surprisingly strong for something so fine. They accumulate in drifts on the downside of the eruptions, collecting in crevices and tangling together like spun gold. During a major eruption, Pele's hair has been found coating surfaces, draping over vegetation, and even drifting onto residential areas miles from the vent. Alongside the hair, you often find Pele's tears, small rounded or teardrop-shaped pieces of volcanic glass, usually black or dark brown and each one between a few millimeters and a couple of centimeters across. They form from the same lava fountain spray, but instead of stretching into filaments, these droplets cool before the wind can elongate them, freeze them into smooth, solid glass beads mid-flight. Sometimes a tear and a strand are still attached, a small dark droplet with a golden glass thread trailing behind it. Pele's hair is not unique to Hawaii. Similar glass fibers have been found near lava fountains in Iceland, Italy, and elsewhere, but the Hawaiian name is stuck, because it was the Hawaiian volcanoes where the phenomenon was first described. The National Park Service at Hawaii Volcanoes National Park receives dozens of packages every year from tourists who took a piece of Pele's hair home, experienced a run of terrible luck, and mailed it back with an apology. Number 13. The Blue Flames of Kawah Ijen in Indonesia On the island of Java, there's a volcano where the lava appears to burn blue. At night, the slopes of Kawah Ijen glow with an electric blue light, this river of blue flame cascading down the dark mountainside, pooling in blue lakes of fire at the bottom of the crater, looking like a volcano from another planet. It is one of the most visually stunning sights in all of volcanology, and the explanation is almost as strange as the phenomena itself. The blue flames aren't actually blue lava. What's happening is this, Kawah Ijen sits on an enormous deposit of elemental sulfur, and the volcano's fumaroles, those are the vents in the crater floor, release sulfuric gases at these very high temperatures, sometimes exceeding 600 degrees Celsius. When these superheated gases hit the comparatively cool air of the surface, they ignite spontaneously, producing flames that burn in the distinctive electric blue color, combusting sulfur. Some of the gas condenses before it burns, forming rivers of molten sulfur that flow down the crater walls, creating the illusion of a blue lava flowing across the land. The phenomena really is only visible at night, and during the day the blue flames are completely washed out by sunlight, and the crater looks like any other volcanic landscape, albeit one with a strikingly turquoise-colored acidic lake at the bottom that measures roughly a kilometer across, and has a pH of less than 0.5. This is one of the most corrosive bodies of water on the planet. But after dark, the crater transforms into something utterly alien. Miners who extract elemental sulfur from the volcano for sale to local industries, which is an incredibly grueling job, work by the light of the blue flames, their silhouettes lit from below by the glow of combusting gas, in a scene that looks like a painting of the underworld. Photographers and tourists hike to the crater rim at two or three in the morning to see the spectacle and the images they bring back to look like science fiction. This is a mountain burning blue against the black Indonesian sky, like a portal into a world where the rules of geology are just a bit different. 12. Lava Tree Molds, Hawaii In the rainforest near Kilauea Volcano, there's a park where you can walk among the ghosts of trees. Not dead trees, ghost trees. Perfect, hollow, cylindrical molds of lava standing upright in the forest, each one preserving the exact shape of a tree trunk that was there when the lava flow swept through. The process works like a natural casting technique. When a lava flow moves through a forested area, the molten rock, which can be around 1200 degrees Celsius, surrounds and encases the tree trunks. The lava is hot enough to ignite and burn the wood, but the tree's moisture cools the lava that's in direct contact with the trunk, causing it to solidify faster than the surrounding flow. As the wood burns away and the lava drains or continues moving, what remains is a hollow cylinder of hardite basalt, in the exact shape of the original tree. At the Lava Tree State Monument, dozens of these lava tree molds stand in a tropical forest that have completely regrown around them in the centuries since the flow. Some are only a few feet tall, these squat cylinders marking where shorter tree stumps once stood. Others stand 10 to 12 feet in the air, hollow and open at the top, their walls encrusted with lichen and moss. You can walk right up to them, look inside, where the inner walls still bear the grain and texture of the tree bark that burned away centuries ago. It's a negative impression of a living thing preserved in rock. The effect is deeply strange, and it's oddly moving. A forest of real living trees growing in the spaces between a forest of stone trees? Each stone tree, a hollow monument, is something alive that was swallowed by lava, consumed by fire, and erased entirely. The tree molds here at Pahoa are one of the most accessible and least known volcanic curiosities in Hawaii, and walking among them in the tropical shade listening to birdsong is an experience that stays with you far longer than you'd expect it to. Number 11. Ordoinio Lengai, Tanzania Every volcano on Earth erupts lava that glows red, orange, or yellow. Every volcano, except one, in northern Tanzania near the southern shore of Lake Nectron in the Great Rift Valley. There's a steep-sided stratovolcano called Ordoinio Lengai, the Mountain of God in the Maasai language, and it erupts lava that's black, not dark red, not deep orange, cooling to dark brown, black, jet black, like ink, flowing out of the crater in thin streams that look less like molten rock and more like motor oil. And then, within hours of eruption, the lava turns white. This volcano is the only one on Earth currently producing natural carbonitide lava, a type of magma made from silicate minerals found in virtually all other volcanic rocks, but from sodium and calcium carbonates. This makes the lava unique in almost every way. It erupts at about 500 to 590 degrees Celsius, that's half the temperature of basaltic lava. It's so cool, relatively speaking, that at night it barely glows at all, a dull red at best, nothing like the brilliant orange rivers of a Hawaiian or Icelandic eruption. During the day, freshly erupted lava appears completely black, as dark and fluid as melted tar. Its viscosity is extraordinary, roughly a thousand times less viscous than basaltic lava, making it the most fluid lava on Earth, and it runs in thin, fast streams across the crater floor. And then, here's the truly strange part. Within hours of erupting, the black lava begins to react with moisture in the atmosphere. The sodium carbonate minerals absorb water and carbon dioxide from the air, and the surface of the flow changes color, from black to gray, from gray to pale brown, from pale brown to stark white. Within days, fresh lava that erupted as a black liquid has turned completely white, giving the summit an appearance that, from a distance, looks like snow. Visitors that don't know any better assume the mountaintop is covered in ice. It's not. It's covered in decomposed, alien lava that turned white because it got wet. The Maasai consider this volcano sacred. It's a dwelling place of their god, Ngai, and for centuries, elders have led pilgrimages to the mountain's base to pray for rain, cattle, and healthy children. But standing on the crater rim, watching black lava flow like water across a floor covered in white powder while the flamingo-filled waters of Lake Natron shimmer in the distance below, it's one of the most otherworldly experiences available on this planet, without leaving the atmosphere. Number 10. Lava Coils and Spirals Every once in a while, a lava flow does something that looks like it was designed by a graphic artist. Instead of flowing in a straight line or just pooling in a shapeless mass, the lava curls back on itself and forms a perfect spiral. It's a coil of solidified rock sitting on the surface of a lava field, looking, for all the world, like a giant cinnamon roll made of basalt. Just don't bite into it. Lava coils, sometimes called lava spirals or lava roses, they're rare and beautiful formations that happen when the surface of a lava flow cools and solidifies while the molten lava beneath it continues to move. If the flow encounters a shear zone, which is a place where two adjacent sections of the flow are moving at different speeds, the cooled surface crust can be twisted, rotated, and rolled into a spiral shape before it fully hardens. The result is a coil of rope-like pahoehoe lava, sometimes only a few inches across, sometimes several feet in diameter, preserved in the lava field. The best-known examples of these lava coils have been found on the Big Island, where the extremely fluid, slow-moving lava from Kilauea create ideal conditions for their formation. Some of the best examples were documented during Kilauea's 1969-74 Mauna Ulu eruption and more recent 2018 Lower East Rift Zone eruption, when massive volumes of extremely fluid lava poured across the land, produced coils ranging from a few inches to over six feet in diameter. Similar formations have also been documented in Iceland, and on the flanks of Mount Etna in Sicily, and in the ancient lava flows of the Canary Islands off the coast of Africa. Now, lava coils aren't common. The vast majority of lava flows don't produce them, because the conditions required are specific and fleeting. Finding an intact lava coil in the field is considered a minor prize among volcanologists, geologists, and hiker, who know enough about terrain to recognize what they're looking at. What makes the lava coils remarkable isn't their rarity, but what they represent. This is a tangible record of something that is normally invisible. Each spiral preserves the exact moment when two adjacent sections of lava flows were moving at different speeds. They are fossils of motion. They're permanent records in a brief, violent, beautiful moment in the life of a lava flow. Number 9. Dirty Thunderstorms, or Volcanic Lightning During certain eruptions, something happens that can look like it was pulled straight from a mythology textbook. Lightning. Bright, jagged, unmistakable lightning, erupting inside the volcanic ash plume itself, flickering and branching through the column of smoke and debris like an electrical storm trapped inside of an explosion. The sky above the volcano turns into a battleground between fire and electricity. Volcanic lightning happens when particles inside an eruptive column collide with enough force and frequency to generate static electricity. It's essentially the same process that creates lightning in a regular storm, except inside of water droplets and ice crystals, it's inside of pulverized rock, volcanic ash, and ice particles. The collisions strip the electrons from the particles, creating regions of positive and negative charge within the plume. When the charge differential becomes large enough, it will discharge, and the result is a bolt of lightning that can be hundreds of feet long, crackling through a cloud of volcanic ash against a backdrop of glowing lava. The phenomenon has been documented at eruptions around the world. The Eyjafjallajökull in Iceland, 2010, the persistently active Sakurajima in Japan, Kalbuko in Chile in 2015, and most spectacularly, at the January 2022 eruption of Tonga's Hungatonga-Hungahaapai, which produced over 590,000 individual events in just 11 hours. It was the most intense lightning storm ever recorded on Earth, volcanic or otherwise. The lightning generated inside the plume was so prolific and so intense, it was detected by weather monitoring sensors on the opposite side of the Pacific Ocean, thousands of miles away. But scientists are still working to fully understand volcanic lightning. It does appear to come in at least two distinct types. Vent lightning, which happens in the dense region directly above the vent, where the eruption column is hottest and most turbulent. And plume lightning, which happens higher up in the ash cloud as it spreads out and cools, behaving more like conventional thunderstorm lightning. Plume lightning can produce long branching bolts that look nearly identical to the lightning in a regular storm, except the cloud they emerge from is made of pulverized rock. Pictures and video of volcanic lightning are among the most shared and awe-inspiring images of all volcanology. It's the combination of orange lava, gray-black ash clouds, and white-blue lightning bolts that creates an almost impossible thing to believe is real. It looks like a special effect, like a movie poster. But it's none of those things. It's just simply what happens when the Earth tears itself open with enough force to generate its own thunderstorm. As if nature itself decided that an eruption alone wasn't sufficiently dramatic enough. And then she added a light show for emphasis. Number 8. Lava Ocean Entry, The Fire Hose When an active flow reaches the edge of a coastline and then pours into the ocean, the collision between the 1200-degree molten basalt and 25-degree water produces one of the most violent and visually spectacular, terrifying natural events on the planet. The lava hits the ocean and the water instantly flashes to steam, not gently or gradually, explosively, producing enormous billowing clouds of white hydrochloric acid vapor called laze. That's a combination of lava and haze that rises up hundreds of feet into the air. This is a relentless orange river meeting the blue ocean in an ongoing explosion of steam, sound, and new land being created in real time. During Kilauea's dramatic 2018 eruption on the Big Island, lava from fissure number 8 in the Lower East Rift Zone carved a river of molten rock through the residential community and entered the ocean through a feature that became known worldwide as the Fire Hose. A concentrated stream of lava shot out from a lava tube opening in a sea cliff about 60 feet above the waterline, arcing through the air in a sustained pressurized jet of glowing orange liquid. The Fire Hose produced a steam plume that was visible from orbit, and the footage, captured by USGS volcanologists and news helicopters, became some of the most widely shared volcanic video of the entire decade. The jet ran continuously for days, pouring hundreds of cubic meters of lava per hour into the ocean. The 2018 eruption was not the first time that lava had reached the ocean. Flows from the Pu'u O'o event had been entering the sea intermittently since 86, but the Fire Hose was unique in its intensity and concentration. The visual was so extraordinary that it fundamentally changed public awareness of what lava ocean entries look like. And for most people who saw it, it was the first time they realized lava doesn't always creep slowly into the sea. Sometimes it sprays in there. Ocean entries are not just visually dramatic, they are geologically active. During the 2018 eruption, the lava flows added over 875 new acres of land to the Big Island of Hawaii, extending the coastline out toward the Pacific. And that new land, though, is unstable. Lava deltas are built on a foundation of loose rubble and can collapse without warning. But it's real, new solid land created from molten rock in the space of a few weeks. The sound of a lava ocean entry is extraordinary too, a continuous roaring hiss overlaid with deep thuds and cracks as chunks of cooling lava will shatter and tumble into the water. The air smells of sulfur and hot metal, and the steam plume can extend miles downwind. At the contact point, the exact line where the fire meets the water, the new earth is being manufactured grain by grain in the most dramatic construction project nature has to offer. Moving on to number seven, columnar basalt. When a thick flow of lava cools slowly and evenly, not too fast, not too unevenly, but just at the right rate, with just the right uniformity, something extraordinary happens. The rock contracts as it cools, and instead of cracking randomly, it'll fracture into a pattern of near-perfect geometric columns, each one a vertical, hexagonal prism of basalt. The result is one of the coolest-looking geological formations, like it was designed by an architect with an obsession for geometry. The most famous example of this is the Giant's Causeway on the northeast coast of Northern Ireland. It's a site consisting of about 40,000 interlocking basalt columns, most of them hexagonal, rising up from the sea like a broken floor of a cathedral built for giants. The columns range from a few inches to about two feet across, and some of them reach heights of over 40 feet. They fit together so precisely, you can run your fingers along the joints and barely feel the gap. This formation was created by an ancient volcanic eruption about 50 to 60 million years ago, when a massive flow of lava cooled and contracted with an evenness that produced this mathematically regular pattern. But the columnar basalt is not unique to Ireland and Scotland, it appears all over the world, wherever the right conditions of lava composition, flow thickness, and cooling rate align. The Devil's Postpile National Monument in California is a dramatic wall of perfectly hexagonal columns, standing about 60 feet high in the Sierra Nevada. This was formed by a lava flow about 100,000 years ago, and exposed by glacial erosion. The Svartavoss Waterfall in Iceland's Vatnajökull National Park drops over a curtain of dark columnar basalt so cool-looking, it directly inspired the design of Reykjavik's landmark church. The organ pipes formation near Melbourne, Australia, the basalt prisms of Santa Maria Regla in the state of Hidalgo in Mexico, and the spectacular columns of the Jeju Island in South Korea. They're all expressions of this same phenomenon. It's the same principle that governs the shape of honeycomb cells in a beehive, and the pattern of cracks in dried mud. Nature, left to its own devices, defaults to hexagons, because hexagons are the most efficient shape. And when lava flow is thick enough, uniform enough, and cools slowly enough, the result is a land of stone columns so perfect that every visitor's first instinct is to assume someone carved them. 6. Pillow Lava Most people think of lava as something that will flow down the side of a mountain, but the vast majority of volcanic activity on the planet doesn't happen on land at all. It happens at the bottom of the ocean, along the 40,000-mile chain of underwater mountain ridges where the tectonic plates are slowly pulling apart. When lava erupts underwater, it doesn't behave anything like the rivers and fountains you see in Hawaii or Iceland. It does something way stranger. It forms pillows. Pillow lava is one of the most distinctive formations on Earth that covers more of the planet's surface than any other type of rock because it covers most of the ocean floor. When basaltic lava erupts beneath the sea, the enormous pressure of the overlying water prevents it from exploding or flowing freely. Instead, the rock oozes out from fractures in the seabed like toothpaste from a tube. The moment the lava touches the cold seawater, which at the bottom of the ocean can be just a few degrees above freezing, the outer surface chills instantly and forms a thin, rubbery skin of cooled glass. But the interior remains molten, and continuing pressure of magma behind it inflates the skin outward, pushing it into a rounded, bulging shape. Individual pillows will range from a few inches to several feet across. Their surfaces are covered in a thin layer of volcanic glass. When you cut up pillow lava in cross-sections, you can see the concentric cooling rings inside. These layers are progressively finer-grained basalt, radiating inward. These pillow lavas, they're not just a curiosity of the deep ocean. Because the tectonic forces have been shoving pieces of ocean floor onto land for billions of years, that's the process called abduction. The ancient pillow lavas can be found on dry land all over the world. The Trudeau Mountains of Cyprus, the Josephine Ophiolite in Oregon, the outcrops in Oman, Newfoundland and Scotland all contain pillow lavas. Walking among these formations is kind of strange and almost disorienting. You're standing on dry land, possibly on a sunlit mountainside. You're at the bottom of an ocean that no longer exists from eruptions that happen before any animal ever crawled onto a beach. These pillows are still perfectly recognizable after hundreds of millions of years. They're smooth, rounded and stacked against one another like a pile of dark loaves of bread. There have been some recent advances in deep-sea exploration technology and it's allowed scientists to observe this pillow lava forming in real time at the mid-ocean ridges. The footage is mesmerizing, glowing orange against the black of the deep ocean, building a new seafloor one pillow at a time down there in total silence, in total dark, miles below the surface. And it's invisible to every human being on Earth except the engineers watching through a camera on a robotic submarine. If you're enjoying the video, please drop a like and a comment down below. It really does help the channel out. Number 5. Lava Tubes Beneath the surface of nearly every major basaltic lava field on Earth, there are tunnels. Not tunnels dug by machines or carved by water. These are tunnels created by the lava itself. Long cylindrical underground passageways through which rivers of molten rock once flowed. When the eruption ends and the lava supply is cut off, the molten river will drain out of these tunnels like water draining from a pipe. These are lava tubes. They're among the most extraordinary natural structures. The formation process is pretty elegant. When a river of fluid lava flows across the surface, the upper layer will cool and solidify first, creating an insulating crust. Beneath the crust, the still molten lava continues to flow, which carves a channel that gradually deepens and widens. Over time, the crust will thicken into a solid roof and the flowing lava beneath it is effectively insulated from the surface, protected from heat loss. And it can travel enormous distances without cooling significantly. The result is an underground river, a liquid rock, flowing through a self-made tunnel at temperatures exceeding 1,100 degrees Celsius for miles. The longest lava tube in the world is the Kazumura Cave on the Big Island of Hawaii, a single continuous tube stretching over 40 miles beneath the flanks of the Kilauea volcano, with a vertical drop of over 3,600 feet from its upper entrance to the coast. It's longer than the longest limestone cave in the U.S., and it was formed by lava flows about 350 to 500 years ago. Walking inside it is like walking inside the artery of a volcano. The walls are smooth, coated in frozen drips and flow marks, and the ceiling occasionally features lavasicles. These are stalactite formations created when the last trickles of lava hanging from the roof cooled down and froze in place. Lava tubes exist wherever this fluid lava has flowed in sufficient volume. Hawaii, Iceland, the Canary Islands, Sicily, Australia, Kenya, Saudi Arabia, and even the lava fields of the Pacific Northwest in the U.S. The Jeju Island lava tube in South Korea, including the spectacular Mangjeonggol Cave, with its soaring ceilings and perfectly preserved formations, is a UNESCO World Heritage Site. The Ondara lava tubes in Queensland, Australia, they were formed by a single eruption about 190,000 years ago, and they stretch for over 100 miles through the outback. Cueva del Viento on Tenerife in the Canary Islands is the longest lava tube in Europe and the fifth longest in the world with over 10 miles of mapped passages. And then there's the extraterrestrial dimension. There is increasingly strong evidence that lava tubes exist and may be far larger than anything on Earth, both on the Moon and Mars. Orbital imaging from NASA and the ESA have revealed what appear to be collapsed lava tube skylights on the lunar surface, these dark circular pits in the basaltic plains of the Maria that match the signature of collapsed tube roofs. Because the Moon has lower gravity than the Earth, lunar lava tubes could be enormous, and some estimates suggest they may be hundreds of meters wide and potentially extend for tens of kilometers. Planetary scientists have proposed that intact lunar lava tubes could serve as a natural shelter for human settlements, offering protection from cosmic radiation, micrometeorite impacts, and the brutal temperature swings of the lunar surface. The idea that humans might one day live inside a lava tube in another world, sheltering in tunnels, carved by the same process that built the caves beneath Kilauea and Etna, is one of the most remarkable connections between everyday geology and the future of our species. The same volcanic force that shaped the land of Hawaii may one day shape humanity's first permanent homes beyond Earth. 4. Obsidian Flows Most lava, when it cools, it turns into a dull gray or dark brown rock. Textured, it's rough, and it's unremarkable to look at. But under very specific conditions, when lava with a high silica content cools extremely rapidly, without enough time for mineral crystals to form, it produces something genuinely extraordinary. Obsidian. Volcanic glass, a jet-black, razor-sharp, glossy material so smooth and lustrous that it looks like it was manufactured in a factory. And in certain parts of the world, obsidian doesn't appear as isolated chunks or small fragments. It appears as entire flows, rivers of black glass that cooled so quickly, they solidified into these glassy sheets that stretch across the land like dark mirrors. The process that creates obsidian is essentially the opposite of what creates columnar basalt. Where columnar basalt requires slow, even cooling, obsidian requires fast cooling. So fast that the atoms in the molten rock don't have the time to arrange themselves into an orderly crystal structure. Instead, they freeze in a disordered, amorphous state. This is why obsidian has no grain, no crystal structure, and no visible texture. It's a super-cooled liquid, a material that was molten one moment and then solid the next, with no time in between for the kind of molecular organization that gives most rocks their rough character. The most spectacular obsidian flows in the world are found in places where thick, silica-rich lava erupted and then cooled rapidly. Big Obsidian Flow at the Newberry Volcanic Monument in central Oregon is one of the youngest lava flows in the continental U.S. It erupted about 1,300 years ago, and the flow is so fresh that almost no vegetation has colonized it yet. Glass Mountain in Northern California's Medicine Lake Highlands is another great example. A massive obsidian flow that erupted about 950 years ago and produced an enormous dome of glassy black rock over 100 feet thick in places, surrounded by pumice and lighter volcanic debris. This flow is so young and so well-preserved it looks like it could have cooled last year. The glassy surface still shines in the sun, and the fractured edges are still razor-sharp. Obsidian Cliff in Yellowstone National Park. This was one of the single most important prehistoric quarry sites in all of North America. For thousands of years, the indigenous peoples traveled hundreds of miles, sometimes from the Great Plains and the Pacific Northwest, to collect obsidian from this cliff, because obsidian fractures with what geologists call a conchoidal break. When struck correctly, it doesn't crumble, it'll fracture in smooth, curved planes that produce edges that are atomically thin. Obsidian blades have been measured at as little as 30 angstroms, about 3 nanometers, which is considerably sharper than the finest surgical steel scalpel ever. So basically, for thousands of years before metallurgy existed, obsidian was the sharpest cutting material available anywhere on the planet. But today, obsidian flows are some of the coolest-looking volcanic landscapes on the planet. Rivers of frozen glass, black and shining, cutting through forests and fields. And they look like they should be liquid, they look like they should belong on another planet, where the geology follows different rules. But they're simply what happens when the right kind of lava cools at the right kind of speed. Number 3. Surtsey On the morning of November 14th, 1963, the crew of a fishing vessel was working in the waters south of Iceland when they noticed something odd. The sea was warm, unusually warm, and it smelled of sulfur. Looking south, they saw what appeared to be a column of dark smoke rising from the surface. Their first thought was a ship was on fire. They radioed the Coast Guard and a rescue response was initiated. And then the ocean tore itself open. What the fishermen witnessed was the beginning of a volcanic eruption on the ocean floor roughly 430 feet below the surface. And over the next several hours, the eruption intensified. Columns of steam, ash, and volcanic debris shot thousands of feet into the sky. By the following morning, something extraordinary had happened. A new island appeared. A piece of land that didn't exist a day before was now sitting in the ocean, steaming and growing. The eruption continued for three and a half years, from November 1963 to June 1967. And by the time it ended, the island of Surtsey stood roughly 500 feet above sea level and covered about one square mile of new terrain. The island was named Surtsey after Surtur, a fire giant of Norse mythology who sets the world ablaze at Ragnarok, a fitting name for a piece of land that was literally forged by fire rising up from the sea. What happened next, though, made it one of the most scientifically valuable pieces of real estate. Almost immediately after the eruption ended, scientists recognized that it offered something unique. A completely sterile, pristine island with no prior biological history sitting in the middle of a productive ocean. Access to it was immediately restricted to authorized researchers only, no tourists, no construction, and no introduction of any foreign species. Scientists began monitoring the ecological development with meticulous care, documenting every plant, insect, bird, and microorganism that arrived. The mosses appeared first within a year or two of the eruption's end, then some grasses, then seabirds began nesting, and their droppings fertilized the soil, allowing even more complex plants to take root. By the 2000s, Tsertsi had over 60 species of vascular plants, several species of nesting seabirds, and a growing community of invertebrates. An entire ecosystem had bootstrapped itself into existence on a pile of rocks in the middle of the Atlantic, with no human assistance of any kind. Tsertsi as a scientific resource, it depends on remaining as free from human contamination as possible. A pristine volcanic canvas on which nature is painting an ecosystem from scratch. But the island itself is slowly shrinking. Wave erosion has reduced much of the area by about half since the eruption ended. The loose volcanic tephra that forms much of the island's coastline is no match for the relentless pounding of the Atlantic. But already, the research from Tsertsi has fundamentally reshaped our understanding of how ecosystems establish themselves. This data has been applied to models of ecological recovery after eruptions in Hawaii, Iceland, and the Philippines, and to theoretical models of how life might colonize habitable surfaces beyond Earth. An island that erupted from the North Atlantic in a column of fire and steam that was named after the Norse god of flame that didn't exist before 63 has become one of the most carefully monitored and most scientifically relevatory places on the planet. It's a piece of new Earth, slowly learning how to be alive. Number 2. Kilauea On the southeastern coast of the Big Island of Hawaii, there's a volcano that's been erupting almost continuously since 1983. A volcano so persistently, reliably, and stubbornly active that it's become the single most studied volcano in the history of science, and arguably, the most important natural laboratory for understanding how the Earth creates new land. This is Kilauea, and over the past four decades, it's produced enough lava to pave a four-lane highway stretching from New York to Los Angeles and back. Kilauea is a shield volcano. This is a broad, gently sloping structure built almost entirely from thousands of overlapping flows of basaltic lava. It sits on the flank of its much larger neighbor, Mauna Loa, on the Big Island of Hawaii, and it draws its magma from the Hawaiian hotspot. This is a plume of abnormally hot mantle rock rising deep from within the Earth and feeding volcanoes in this part of the Pacific for at least 70 million years. The numbers from Kilauea's recent eruptive history are pretty amazing. The Pu'u O'o eruption, which lasted from 1983 to 2018, was one of the longest-lived rift zone eruptions ever. Over those 35 years, Kilauea produced an estimated 4.5 cubic kilometers of lava. That lava flowed through tubes and surface channels down the south flank of the volcano, through the forests and over roads, and occasionally through residential communities and into the Pacific, where it added over 500 acres of brand new land. Then, in 2018, everything escalated. A massive eruption in the lower east rift zone opened 24 volcanic fissures in a residential community about 25 miles from the summit. Rivers of lava, some of them moving at highway speed, poured through the neighborhood, consuming over 700 homes. The eruption produced about 0.8 cubic kilometers of lava in just three months, a volume that would have taken the previous eruption years to match. By the time that eruption ended, Kilauea had added about 875 acres of new land to the Big Island of Hawaii. Kilauea is not the most explosive volcano on Earth. It's not the tallest and it's not the most dangerous in the conventional sense. The eruptions are generally non-explosive and effusive, producing rivers of lava. What Kilauea is, beyond any reasonable doubt, is the most creatively productive volcano. It builds land and it manufactures the coastline. Year after year, decade after decade, in a process that's been ongoing, with a few interruptions, for about 600,000 years. The Hawaiian Volcano Observatory, operated by the USGS and perched on the rim of Kilauea's summit caldera, is one of the oldest volcano observatories in the world. It was founded in 1912 by Thomas Jagger, with the explicit goal of studying eruptions to save lives. Almost everything we know about how shield volcanoes work, how lava tubes form, and how eruptions evolve over time comes, in significant part, from data collected here. The volcano has erupted again since 2018. Lava returned to the summit caldera in December of 2020, and some further eruptions happened in 2021 and 23, and beyond. Each new eruption is monitored in real time by an array of seismometers, tiltmeters, GPS stations, and thermal cameras. Standing on the coast of the Big Island, watching fresh lava from Kilauea hiss and steam as it pours into the ocean, you're witnessing the planet building itself. Every square inch of ground you've ever stood on is happening right in front of you in real time at a temperature of 1200 degrees Celsius. It is creation itself, rendered in liquid rock, and it never gets old. Number 1. Nyiragongo, the world's most dangerous lava lake. In the Eastern Democratic Republic of Congo, on the edge of the city of Goma, a bustling city of about 2 million people, there's a volcano with a lava lake at its summit that's been burning almost continuously since at least 1928. The lake is about 700 feet across and it sits inside a steep-walled crater over 3,000 feet in diameter. The surface of the lake is churning, spattering, and it's incandescent. It's a sheet of molten basaltic lava that glows orange by day and lights up the clouds above the volcano like a furnace at night. This is Mount Nyiragongo and it contains the largest persistent lava lake on Earth. Nyiragongo has erupted dozens of times in recorded history and its lava is chemically unusual. It's nephronalanite, a silica-poor composition that makes it extraordinarily fluid. Nyiragongo's lava has the lowest viscosity of any known continental volcanic lava, which means that when the lava erupts and the lava lake drains, the molten rock does not creep slowly down the mountainside like thick flows of Mount Etna or Kilauea. It runs. It pours down the flanks of the volcano like a river of glowing liquid. It's been clocked at up to 60 miles an hour, faster than a person can drive. It is, by a considerable margin, the fastest-flowing lava ever recorded. But the lava lake itself is one of the most mesmerizing sights on Earth. It's one of the most difficult to visit, too. Reaching the crater rim requires a five- to six-hour hike up the forested flanks of the volcano. Hikers who make the climb camp on the crater rim overnight and then experience the looking down into the active lava lake after dark, a boiling, glowing, spattering circle of molten rock hundreds of feet down. The lava illuminates the crater walls in orange and red while the lake's surface churns and occasionally erupts in fountains that throw incandescent lava dozens of feet into the air. It's described by virtually everyone who has seen it as one of the most amazing yet terrifying sights they've ever seen. In January of 2002, it erupted catastrophically. Fractures opened on the southern flank of the volcano and the lava lake drained through them in a matter of hours, sending rivers of extremely fluid lava racing down the mountain. The lava reached Goma. It cut the city in half and it destroyed roughly 15% of the buildings and it flowed all the way to the shores of Lake Kivu, where it entered the water and sent up enormous clouds of steam. Over 100 people lost their lives and an estimated 400,000 of them were displaced. The eruption was a stark and tragic reminder of what makes Ngiragongo so dangerous. It's not just the size of the lava lake or the frequency of the eruptions, but the speed of the lava itself. The volcano erupted again in May of 2021, with lava again flowing toward Goma and forcing the evacuation of the city. The lava lake reformed within months after the eruption and it's active to this day, reminding everyone within sight of the red sky above the crater that the most dangerous lava lake in the world is still open for business. But what makes Ngiragongo number one on this list is not just the size of the lava lake or the terrifying speed of the lava, or the dramatic proximity of a major city to one of the most active volcanic threats on the planet. It's the combination of all of those things existing at the same time in one place right now. You can see the glow from Goma. You can see it from Lake Kivu. On clear nights, pilots approaching the region can see the red light reflected off the clouds from hundreds of miles away, as if the earth itself just left the light on. There is no lava phenomenon anywhere on this planet that is more visually dramatic. And more scientifically cool, more logistically terrifying, or more viscerally undeniably alive than the lava lake of mountain Ngiragongo. It is the earth at its most raw and its most powerful. A churning pool of liquid rock at a thousand degrees Celsius burning in the heart of Africa. It is still very much capable of opening up and pouring itself across the land whenever and wherever it decides that the time has come. So if you enjoyed this video, you're going to love our next one on the top 15 most radioactive places in the world. I'll see you over there.