2. Pico do Fogo is a stunning volcano located in Cape Verde. This volcano, with an elevation of 2,829 meters above sea level, is the highest peak of Cape Verde. Its last recorded explosion occurred in 1675.
Lightning crackles over Japan on Friday as ash and lava erupt from Shinmoedake peak, one of the calderas of the Kirishima volcano complex.
Shinmoedake began erupting Wednesday, coating nearby villages and farms with ash and prompting authorities to ask for voluntary evacuations within a 1.2-mile (2-kilometer) radius.
Volcanic lightning is still a mystery, though it may be that electrically charged silica—part of magma—interacts with the atmosphere when it flies out of a volcano, Steve McNutt of the Alaska Volcano Observatory told National Geographic News in February 2010.
A volcano is an opening in Earth’s crust that allows molten rock from beneath the crust to reach the surface. This molten rock is called magma when it is beneath the surface and lava when it erupts or flows from a volcano. Along with lava, volcanoes also release gases, ash, and rock. It’s a super hot mix that can be both incredibly destructive and creative.
Volcanoes form at the edges of Earth’s tectonic plates. These huge slabs of Earth’s crust travel atop the partly molten mantle, the layer beneath the crust. If you could see the plates, you might think they look like pieces of a puzzle because the edges fit together. But these puzzle pieces move, usually at the unnoticeable pace of only a few inches every year. Sometimes, though, plates collide with one another or pull apart, and it’s at these active zones where volcanoes form. Volcanoes may also erupt in areas called hotspots where the crust is thin.
Volcanoes erupt in different ways, producing different landforms. Steep, cone-shaped volcanoes form when plates collide. All the pressure and heat of the collision make for a violent eruption. The cone forms when lava and other material eject and build up around the opening. This type of volcano is known as a stratovolcano, and Mt. Rainier is a good example. Sometimes an eruption is so violent that the top of the volcano collapses, leaving a huge pit or caldera. You can see calderas in Yellowstone National Park and Crater Lake. When plates pull apart, lava escapes through the rift. This more gentle flow creates new crust on the seafloor and wide, rounded volcanoes on the surface called shield volcanoes. Hawaii’s Kilauea is a shield volcano. It is also an example of a volcano that formed over a hotspot.
Volcanic eruptions can be deadly. Eruptions of Krakatau and Tambora in Indonesia caused the deaths of more than 100,000 people. Dangerous as they are, volcanoes also build and shape the land, creating mountains and new seafloor and depositing minerals and nutrients that enrich soil.
Satellite images in the gallery are courtesy of Geo Eye.
What sets supervolcanoes apart is their ability to produce at least 240 cubic miles (1,000 cubic kilometers) of lava in a single blast. The Hong Kong supervolcano theoretically could have done so, though its last major eruption, 140 million years ago, appears to have produced 72 cubic miles (300 cubic kilometers) of ash and lava from an 11-mile-wide (18 kilometer-wide) caldera—enough to cover all Hong Kong.
Danger aside, their photography is unlike any other. Likewise, their satisfaction is unequivocal. “The views are really something special and completely unique every time,” Kale says. “I wouldn’t rather be doing anything else.” (Photos by Caters News Agency)
One of Ireland’s many stunning natural wonders is the Giant’s Causeway, located on the island’s northeast coast just a few miles from the town of Bushmills, in County Antrim. Like much of Irish lore, the Giant’s Causeway is steeped in as much myth and legend as actual fact. Certainly, the causeway was known to hunter-gatherer tribes who inhabited these lands for millennia, but its modern discovery is credited to the Bishop of Derry in 1692. In academic circles, the debates ranged from it being built by men with tools, to it being made by natural forces, to even being created by a giant, named Finn McCool.
Geologic History Although there are an abundance of tall tales, and myths describing colourful ways the Giant’s Causeway came into being, the actual, natural history is a bit less exciting. The actual history is that the rock formations were created by a lava flow some 65 million years ago by molten basalt rising through a chalk bed, and then cooling and cracking to form the tall columns that make up the causeway. The cracking produced interesting geometric designs, and although most of the columns are six-sided, others have between four and eight sides. The rapid cooling that took place is likely the result of the lava coming into contact with water. At the time of this monument’s creation, Ireland lie near the equator, shifting northward with the movement of the tectonic plates. The causeway’s 40,000 columns range in height, with the tallest around 36 feet high.