A Wisdom Archive on volcanic ash

Volcanic ash is the term for very fine rock and mineral particles less than 2 mm in diameter that are ejected from a volcanic vent. Ash is created when solid rock shatters and magma separates into minute particles during explosive volcanic activity. The usually violent nature of an eruption involving steam (phreatic eruption) results in the magma and perhaps solid rock surrounding the vent, being torn into particles of clay to sand size. The plume that is often seen above an erupting volcano is composed primarily of ash and ste ... Including:

• Volcanic ash - Characteristics
• Volcanic ash - Dangers
• Volcanic ash - Ash and aviation
• Volcanic ash - Atmospheric effects

Read more here: » Volcanic ash: Encyclopedia - Volcanic ash

Volcanic ash jams machinery. This poses a great danger to aircraft flying near ash clouds. There are many instances of damage to jet aircraft as a result of an ash encounter. Engines may quit, and fuel and water systems may become fouled, requiring repair. After the Galunggung, Indonesia volcanic event in 1982, a British Airways Boeing 747 flew through an ash cloud that fouled all 4 engines, stopping them. The plane descended from 36,000 feet to only 12,000 feet bef ...

Read more here: » Volcanic ash: Encyclopedia II - Volcanic ash - Ash and aviation

Volcanic cones are among the simplest volcano formations. They are built by fragments (called ejecta) thrown up (ejected) from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. Types typically differentiated are spatter cone, cinder cone, ash cone, and tuff cone.

Including:

• Volcanic cone - Spatter Cone
• Volcanic cone - Ash Cone
• Volcanic cone - Cinder Cone

Read more here: » Volcanic cone: Encyclopedia - Volcanic cone

A volcanic winter is the reduction in temperature caused by volcanic ash and droplets of sulfuric acid obscuring the sun, usually after a volcanic eruption. Volcanic winter - Effects on life. The causes of the bottleneck phenomenon, i.e. a sharp decrease in a species' population immediately followed by a period of great genetic divergence (differentiation) among survivors - might be attributed to volcanic winters. According to anthropologist Stanley Ambrose, such events diminish the population size to "leve ... Including:

• Volcanic winter - Effects on life
• Volcanic winter - Ancient case of volcanic winters
• Volcanic winter - Recent cases of volcanic winter

Read more here: » Volcanic winter: Encyclopedia - Volcanic winter

Blue Amber is a rare coloration of amber. It most commonly is found in the Dominican Republic and well regarded by collectors for its value. Blue Amber - Origin. It is not fully understood what causes the blue coloration. One theory links the rare properties to the occurrence of volcanic ash or dust which was present when the resin was first pressed out from Hymenaea protera millions of years ago. Another suggests that due to volcanic activity hot lava must have flown over those areas where regular a ... Including:

• Blue Amber - Origin
• Blue Amber - Is it really blue?

Read more here: » Blue Amber: Encyclopedia - Blue Amber

Assyrtiko or Asyrtiko is the indigenous white wine grape of the island of Santorini, Greece. Considered Greece's best white grape varietal by experts such as Nico Manessis, author of The Greek Wine Guide (Olive), assyrtiko is widely planted in the arid volcanic-ash-rich soil of Santorini and other Aegean islands, mainly on Paros (as well as in other scattered regions of Greece like Chalkidiki for example), where the average age of the root stock is 70 years, and many vines date back 150 years or more. The grapes are large and round, and have a ... Including:

• Assyrtiko - External link

Read more here: » Assyrtiko: Encyclopedia - Assyrtiko