A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, gases to escape from a magma chamber below the surface. Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle. Therefore, on Earth, volcanoes are found where tectonic plates are diverging or converging, most are found underwater. For example, a mid-oceanic ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can form where there is stretching and thinning of the crust's plates, e.g. in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande Rift in North America. This type of volcanism falls under the umbrella of "plate hypothesis" volcanism. Volcanism away from plate boundaries has been explained as mantle plumes; these so-called "hotspots", for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core–mantle boundary, 3,000 km deep in the Earth.
Volcanoes are not created where two tectonic plates slide past one another. Erupting volcanoes can pose many hazards, not only in the immediate vicinity of the eruption. One such hazard is that volcanic ash can be a threat to aircraft, in particular those with jet engines where ash particles can be melted by the high operating temperature. Large eruptions can affect temperature as ash and droplets of sulfuric acid obscure the sun and cool the Earth's lower atmosphere. Volcanic winters have caused catastrophic famines; the word volcano is derived from the name of Vulcano, a volcanic island in the Aeolian Islands of Italy whose name in turn comes from Vulcan, the god of fire in Roman mythology. The study of volcanoes is sometimes spelled vulcanology. At the mid-oceanic ridges, two tectonic plates diverge from one another as new oceanic crust is formed by the cooling and solidifying of hot molten rock; because the crust is thin at these ridges due to the pull of the tectonic plates, the release of pressure leads to adiabatic expansion and the partial melting of the mantle, causing volcanism and creating new oceanic crust.
Most divergent plate boundaries are at the bottom of the oceans. Black smokers are evidence of this kind of volcanic activity. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed. Subduction zones are places where two plates an oceanic plate and a continental plate, collide. In this case, the oceanic plate subducts, or submerges, under the continental plate, forming a deep ocean trench just offshore. In a process called flux melting, water released from the subducting plate lowers the melting temperature of the overlying mantle wedge, thus creating magma; this magma tends to be viscous because of its high silica content, so it does not attain the surface but cools and solidifies at depth. When it does reach the surface, however, a volcano is formed. Typical examples are the volcanoes in the Pacific Ring of Fire. Hotspots are volcanic areas believed to be formed by mantle plumes, which are hypothesized to be columns of hot material rising from the core-mantle boundary in a fixed space that causes large-volume melting.
Because tectonic plates move across them, each volcano becomes dormant and is re-formed as the plate advances over the postulated plume. The Hawaiian Islands are said to have been formed in such a manner; this theory, has been doubted. The most common perception of a volcano is of a conical mountain, spewing lava and poisonous gases from a crater at its summit; the features of volcanoes are much more complicated and their structure and behavior depends on a number of factors. Some volcanoes have rugged peaks formed by lava domes rather than a summit crater while others have landscape features such as massive plateaus. Vents that issue volcanic material and gases can develop anywhere on the landform and may give rise to smaller cones such as Puʻu ʻŌʻō on a flank of Hawaii's Kīlauea. Other types of volcano include cryovolcanoes on some moons of Jupiter and Neptune. Active mud volcanoes tend to involve temperatures much lower than those of igneous volcanoes except when the mud volcano is a vent of an igneous volcano.
Volcanic fissure vents are linear fractures through which lava emerges. Shield volcanoes, so named for their broad, shield-like profiles, are formed by the eruption of low-viscosity lava that can flow a great distance from a vent, they do not explode catastrophically. Since low-viscosity magma is low in silica, shield volcanoes are more common in oceanic than continental settings; the Hawaiian volcanic chain is a series of shield cones, they are common in Iceland, as well. Lava domes are built by slow eruptions of viscous lava, they are sometimes formed within the crater of a previous volcanic eruption, as in the case of Mount Saint Helen
The Atlanta & Edgewood Street Railroad Company of Atlanta, Georgia was organized in 1886 by Joel Hurt, C. W. Hubner, H. E. W. Palmer, W. P. Inman, Peter Lynch, R. C. Mitchell, Asa Griggs Candler, J. P. McDonald, J. G. Reynolds, A. F. Moreland, P. H. Harralson, it was authorized to run horsecars along Foster Street to what was the separate village of Edgewood. Soon thereafter the Atlanta & Edgewood introduced Atlanta's first electric streetcar service in 1889. Hurt owned the East Atlanta Land Company; the cars featured oak interiors and plate glass windows valued at $4,000. The steel rails were gauges heavier than those used on the Georgia Railroad which ran parallel just to the south; the rails were surrounded by paving made of Belgian block. The streetcar was designed to make and comfortably accessible Hurt's garden suburb, Inman Park. Streetcars in Atlanta Timeline of mass transit in Atlanta "Atlanta and Edgewood Street Railroad Company". Atlanta's Streetcars of the Nineteenth Century. Archived from the original on October 3, 2011.
Acts passed by the General Assembly of Georgia 1886. Atlanta, Georgia: George W. Harrison, State Printer. 1887. P. 162 – via Google Books. Garrett, Franklin M.. Atlanta and Environs: A Chronicle of Its People and Events, 1880s-1930. University of Georgia Press. P. 188. ISBN 0820339040 – via Google Books
Takako Minekawa is a Japanese musician and writer. As an accomplished all-around musician, Minekawa's musical skills set her outside of the J-Pop "idol" tradition: she writes and composes most of her material, singing quirky lyrics about subjects such as clouds and the color white, with her love of Kraftwerk and French Pop Music showing through her unique experimental sound, she makes use of vintage Casio keyboards and analog Moog synthesizers, as well as vocoders and other electronic instruments. Her live debut was in 1990, calling herself Mamene Kirerie as a member of the group Fancy Face Groovy Name alongside Kahimi Karie and backed by Flipper's Guitar, she was a member of the band L⇔R before releasing her solo debut, Chat Chat in 1994. Although as a child Minekawa had a short acting career, this interest has not resurfaced in her adult life, she has written professionally, as regular columnist in the Japanese edition of Keyboard Magazine. She married fellow musician Keigo Oyamada in 2000.
They divorced in 2012. The pair have collaborated on several projects. Cornelius remixed some of her songs, including the well-received "Milk Rock", he produced a few songs in her album Fun9. Minekawa's musical influences are as varied as her lyrics. An avowed fan of French pop, some of her favorite French artists include Françoise Hardy and Pierre Bachelet; the influence of the British band Stereolab can be heard in her music. While there are touches of humor in her lyrics and tone, she is a sincere fan of Krautrock the earlier works of electronic music pioneers Kraftwerk, to whom she dedicated the song Kraftpark! In an interview, Minekawa explained her admiration for the band: "I decided to describe the landscape of Kraftpark with sound and narration; this song is not a parody of Kraftwerk. I did it because I love them!" Another influence is former Yellow Magic Orchestra member Haruomi Hosono, who she paid tribute to with cover versions of his song "Kaze no Tani no Nausicaa", in 1995 and again in 2007 with Ryuichi Sakamoto.
After a 13-year hiatus, Minekawa recorded a new album, Toropical Circle with collaborator Dustin Wong, in 2013. Chat Chat Baroque in Winter Roomic Cube Athletica Cloudy Cloud Calculator Ximer...c.c.c.remix Fun 9 Recubed Maxi On Toropical Circle Savage Imagination Are Euphoria Official website Nippop Profile | Takako Minekawa US music label page – Emperor Norton Records Takako Minekawa at AllMusic Fan site with extensive gallery