Nyiragongo Lava, Congo - Photograph by Carsten Peter, National Geographic Cradling one of the world's largest and least studied lava lakes& than 700 feet across and possibly miles deep& has twice sent molten rock racing toward residents of Goma.
The mountain-like mounds that we associate with volcanoes are what remain after the material spewed during eruptions has collected and hardened around the vent. This can happen over a period of weeks or many millions of years.
It’s technically a pallasitic meteorite, and the green-yellow transparent minerals are called olivine, which composes most of the upper mantle of the Earth. The metallic parts are an iron-nickel alloy.
Night Supercell An amazing supercell tracks across southern Nebraska, producing other-worldy storm structures. At times this storm looked like a giant tsunami in the sky. The supercell formed after two supercells merged near McCook Nebraska.