Duddly
How are Fulgurites formed and what are they.
Please Explain in detail with your sources
Answer
From the NSSL (National Severe Storms Laboratory) FAQ
What is it called when lightning strikes sand and melts it, forming a tube?
Fulgarite. Fulgarite has been found all over the world, but is relatively rare. The color depends on the minerals in the sand that was struck.
http://www.nssl.noaa.gov/primer/lightning/ltg_faq.shtml
FULGURITES are rocks produced by the intense heat of lightning striking the ground. They normally consist of glass, created when the lightning melts the sand and rock, with embedded sand and rock fragments. Due to the rapid heating of the materials making up the fulgurites, they also contain abundant gas pockets that are usually lined with glass.
http://www.gc.maricopa.edu/earthsci/imagearchive/fulgarites.htm
Most people have never seen a fulgurite, and many that have probably did not realize what it was at the time. Fulgurites are natural tubes or crusts of glass formed by the fusion of silica (quartz) sand or rock from a lightning strike. Their shape mimics the path of the lightning bolt as it disperses into the ground.
All lightning strikes that hit the ground are capable of forming fulgurites. A temperature of 1800 degrees Celsius is required to instantaneously melt sand and form a fulgurite (most lightning strikes have a temperature of 2500 degrees Celsius). Fulgurites have been found worldwide, but are relatively rare.
Two types of fulgurites have been recognized: sand and rock fulgurites. Sand fulgurites are the most common and are generally found in beach or desert regions containing clean (free of fine-grained silt or clay), dry sand. They resemble roots or branching tube-like structures that have a rough surface, covered with partially melted sand grains.
Sand fulgurite tubes have a glassy interior, due to rapid cooling and solidification of the sand after the lightning strike. The size and length of a fulgurite depends on the strength of the lightning strike and the thickness of the sand bed. Many sand fulgurites average 1 or 2 inches in diameter and can be up to 30 inches long. Sand fulgurites have been found in Utahâs deserts and on top of some of the higher summits of the Wasatch Range.
Rock fulgurite (circled in white) found on quartzite at the summit of Mount Raymond in the Wasatch Range, Salt Lake County, Utah. Hammer for scale.
Coatings or crusts of glass formed on rocks from a lightning strike are called rock fulgurites. These fulgurites are found as veins or branching channels on a rock surface or lining preexisting fractures within the host rock. Rock fulgurites are primarily found on the top or within several feet of mountain summits.
Mountain peaks are natural lightning rods that are repeatedly blasted by lightning strikes during severe weather. Rock fulgurites can be found throughout many of the mountain ranges of the world, including the French Alps (Mont Blanc), Pyrenees Range, and western U.S. mountains such as the Sierra Nevada, volcanic peaks of the Cascade Range, Rocky Mountains, and Utahâs Wasatch Range.
While hiking in the summer of 2003, I discovered both sand and rock fulgurites on some of the higher summits of the Wasatch Range. I observed very small sand fulgurites (an inch or less) in some of the surface float on top of Mount Raymond (10,241 feet) and Broads Fork West Twin (11,328 feet).
I also found rock fulgurites on top of Mount Raymond, Broads Fork West Twin, Mount Baldy (11,068 feet), and Mount Timpanogos (11,749 feet). Some of the rock fulgurites, such as those found on Mount Timpanogos, are the result of human activity (a steel shelter placed on top of the peak attracts lightning).
In the Wasatch Range, rock fulgurites appear to be confined to mountaintops composed chiefly of quartzite, but summits consisting of other rock types could have them as well.
So, the next time you go hiking or exploring be on the lookout for fulgurites! It is very possible new fulgurite discoveries await the adventurer on many of the higher summits and desert areas of Utah.
http://geology.utah.gov/surveynotes/gladasked/gladfulgurites.htm
Tell me about Sosua, Dominican Republic.?
brocaknows
I'm thinking about heading over there with some friends. Anyone who has been there- are the beaches very crowded? museums, activities, shopping? would you recommend another area? what's the nightlife like? What kind of bars/clubs? What would you say the average age was? Thanks!
Answer
Sosua, located approximately 25 km east of Puerto Plata, and less than 10 km east from Puerto Plata International Airport , is divided into two areas - Los Charamicos (western side) and El Batey (eastern side). Los Charamicos is predominantly occupied by Dominicans who make their living through fishing, tourism jobs or small businesses. El Batey first saw growth in the early 1940's, when an influx of Jewish settlers, escaping Nazi Germany, settled here and developed a dairy industry. Productos Sosua, a producer of dairy products and grocery store chain, is one of the businesses they started that still thrives today. Although many of these settlers moved on, their legacy continues with a small local Jewish community and Synagogue. After this period there was a boom of wealthy Dominicans and Expats whom built beach homes here. The 1970's and 80's saw an influx of tourism to the area, and many hotels, restaurants and shops were built. Over the years since, the town did experience some ups and downs, with pockets of 'sex tourism' earning the area a bit of a seedy reputation. In the last few years, Expats and others who make this town their home, rallied to clean it up and invest in its future. New hotels have been built and tourism has increased to the area. Although the town offers numerous restaurants, bars, activities and 5 beaches to choose from, it's Sosua Beach that amazes most of its visitors. This 1/2 km of beach has beautiful soft, white sand, clear turquoise waters, and sits sheltered in a small cove surrounded by amazing high coral cliffs. Just behind the beach there are plenty of souvenir shops and restaurants vying for your business. This is also where most snorkeling and diving tours depart from. It is close to Puerto Plata and there shopping is the business, museums you have a few. The Jewish Museum, and you have tons of activities. jetskiing, snorkeling, ther is always a merengue party or something going on. It is never a dull moment anywhere. It is on like donkey Kong at night. enjoy.
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