![]() ![]() One of the longest fulgurites to have been found in modern times was a little over 4.9 m (16 ft) in length, and was found in northern Florida. Or they may form directly on sedimentary surfaces. ![]() Fulgurites are usually fragile, making the field collection of large specimens difficult.įulgurites can exceed 20 centimeters in diameter and can penetrate deep into the subsoil, sometimes occurring as far as 15 m (49 ft) below the surface that was struck. ![]() Branching fulgurites display fractal-like self-similarity and structural scale invariance as a macroscopic or microscopic network of root-like branches, and can display this texture without central channels or obvious divergence from morphology of context or target (e.g. Other types of fulgurites are usually vesicular, and may lack an open central tube their exteriors can be porous or smooth. The interior of Type I (sand) fulgurites normally is smooth or lined with fine bubbles, while their exteriors are coated with rough sedimentary particles or small rocks. However, lightning can strike man-made objects, resulting in colored fulgurites. Brightly colored lechatelierites resembling fulgurites are usually synthetic and reflect the incorporation of synthetic materials. Downed high voltage power lines have produced brightly colored lechatelierites, due to the incorporation of copper or other materials from the power lines themselves. Lechatelierite similar to fulgurites can also be produced via controlled (or uncontrolled) arcing of artificial electricity into a medium. Iron is a common impurity that can result in a deep brownish-green coloration. Most natural fulgurites fall on a spectrum from white to black. Material properties (size, color, texture) of fulgurites vary widely, depending on the size of the lightning bolt and composition and moisture content of the surface struck by lightning. Because fulgurites are generally amorphous in structure, fulgurites are classified as mineraloids. Many fulgurites show some evidence of crystallization: in addition to glasses, many are partially protocrystalline or microcrystalline. The primary SiO 2 phase in common tube fulgurites is lechatelierite, an amorphous silica glass. Description įulgurites are formed when lightning strikes the ground, fusing and vitrifying mineral grains. Fulgurites have no fixed composition because their chemical composition is determined by the physical and chemical properties of whatever material is being struck by lightning.įulgurites are structurally similar to Lichtenberg figures, which are the branching patterns produced on surfaces of insulators during dielectric breakdown by high-voltage discharges, such as lightning. This results in the formation of generally hollow and/or vesicular, branching assemblages of glassy tubes, crusts, and clumped masses. Such current may propagate into silica-rich quartzose sand, mixed soil, clay, or other sediments, rapidly vaporizing and melting resistant materials within such a common dissipation regime. When ordinary negative polarity cloud-ground lightning discharges into a grounding substrate, greater than 100 million volts (100 MV) of potential difference may be bridged. When composed of silica, fulgurites are classified as a variety of the mineraloid lechatelierite. So the expression "out of the blue" is completely accurate - if you can hear thunder, it's possible, if not very likely, that lightning from a nearby thunderstorm can make it to wherever you are.Fulgurites (from Latin fulgur 'lightning', and -ite), commonly called " fossilized lightning", are natural tubes, clumps, or masses of sintered, vitrified, and/or fused soil, sand, rock, organic debris and other sediments that sometimes form when lightning discharges into ground. states - Mississippi, Louisiana and Texas - in 2020. While most lightning bolts are 2 to 3 miles (3.2 to 4.8 kilometers) long, the world record flash was observed to stretch 477.2 miles (768 kilometers) across three U.S. Only about 10 percent of the victims of lightning strikes result in deaths - usually from cardiac arrest or irrevocable brain damage - which is somewhat surprising, considering a lightning bolt is about 50,000 degrees Fahrenheit (27,760 degrees Celsius) - about five times hotter than the surface of the sun.Īlthough a lightning bolt is only about an inch in diameter (2 to 3 centimeters), it can stretch for miles. According to the National Weather Service, between 19, an average of 43 lighting-related deaths were reported in the United States each year. Lightning is the most beautiful and dangerous aspect of a storm. What is the science behind this beautiful - but dangerous - natural phenomenon? ClassicStock/Getty Images Flashes of lightning against a dark sky create an otherworldly effect. ![]()
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