Lava is molten rock generated by geothermal energy and expelled through fractures in planetary crust or in an eruption at temperatures from 700 to 1,200 °C. The structures resulting from subsequent solidification and cooling are sometimes described as lava; the molten rock is formed in the interior of some planets, including Earth, some of their satellites, though such material located below the crust is referred to by other terms. A lava flow is a moving outpouring of lava created during a non-explosive effusive eruption; when it has stopped moving, lava solidifies to form igneous rock. The term lava flow is shortened to lava. Although lava can be up to 100,000 times more viscous than water, lava can flow great distances before cooling and solidifying because of its thixotropic and shear thinning properties. Explosive eruptions produce a mixture of volcanic ash and other fragments called tephra, rather than lava flows; the word lava comes from Italian, is derived from the Latin word labes which means a fall or slide.
The first use in connection with extruded magma was in a short account written by Francesco Serao on the eruption of Vesuvius in 1737. Serao described "a flow of fiery lava" as an analogy to the flow of water and mud down the flanks of the volcano following heavy rain; the composition of all lava of the Earth's crust is dominated by silicate minerals: feldspars, pyroxenes, amphiboles and quartz. Silicate lavas can be classified into three chemical types: felsic and mafic; these classes are chemical. Felsic or silicic lavas such as rhyolite and dacite form lava spines, lava domes or "coulees" and are associated with pyroclastic deposits. Most silicic lava flows are viscous, fragment as they extrude, producing blocky autobreccias; the high viscosity and strength are the result of their chemistry, high in silica, potassium and calcium, forming a polymerized liquid rich in feldspar and quartz, thus has a higher viscosity than other magma types. Felsic magmas can erupt at temperatures as low as 650 to 750 °C.
Unusually hot rhyolite lavas, may flow for distances of many tens of kilometres, such as in the Snake River Plain of the northwestern United States. Intermediate or andesitic lavas are lower in aluminium and silica, somewhat richer in magnesium and iron. Intermediate lavas form andesite domes and block lavas, may occur on steep composite volcanoes, such as in the Andes. Poorer in aluminium and silica than felsic lavas, commonly hotter, they tend to be less viscous. Greater temperatures tend to destroy polymerized bonds within the magma, promoting more fluid behaviour and a greater tendency to form phenocrysts. Higher iron and magnesium tends to manifest as a darker groundmass, occasionally amphibole or pyroxene phenocrysts. Mafic or basaltic lavas are typified by their high ferromagnesian content, erupt at temperatures in excess of 950 °C. Basaltic magma is high in iron and magnesium, has lower aluminium and silica, which taken together reduces the degree of polymerization within the melt. Owing to the higher temperatures, viscosities can be low, although still thousands of times higher than water.
The low degree of polymerization and high temperature favors chemical diffusion, so it is common to see large, well-formed phenocrysts within mafic lavas. Basalt lavas tend to produce low-profile shield volcanoes or "flood basalt fields", because the fluidal lava flows for long distances from the vent; the thickness of a basalt lava on a low slope, may be much greater than the thickness of the moving lava flow at any one time, because basalt lavas may "inflate" by supply of lava beneath a solidified crust. Most basalt lavas are of pāhoehoe types, rather than block lavas. Underwater, they can form pillow lavas, which are rather similar to entrail-type pahoehoe lavas on land. Ultramafic lavas such as komatiite and magnesian magmas that form boninite take the composition and temperatures of eruptions to the extreme. Komatiites contain over 18% magnesium oxide, are thought to have erupted at temperatures of 1,600 °C. At this temperature there is no polymerization of the mineral compounds, creating a mobile liquid.
Most if not all ultramafic lavas are no younger than the Proterozoic, with a few ultramafic magmas known from the Phanerozoic. No modern komatiite lavas are known, as the Earth's mantle has cooled too much to produce magnesian magmas; some lavas of unusual composition have erupted onto the surface of the Earth. These include: Carbonatite and natrocarbonatite lavas are known from Ol Doinyo Lengai volcano in Tanzania, the sole example of an active carbonatite volcano. Iron oxide lavas are thought to be the source of the iron ore at Kiruna, Sweden which formed during the Proterozoic. Iron oxide lavas of Pliocene age occur at the El Laco volcanic complex on the Chile-Argentina border. Iron oxide lavas are thought to be the result of immiscible separation of iron oxide magma from a parental magma of calc-alkaline or alkaline composition. Sulfur lava flows up to 250 metres 10 metres wide occur at Lastarria volcano, Chile, they were formed by the melting of sulfur deposits at temperatures as low as 113 °C.
The Association of Gospel Rescue Missions known as the International Union of Gospel Missions, is a nonprofit organization in the United States, founded in 1913. AGRM's member missions work to provide emergency shelter, permanent housing, food and family services, education and job training programs. In addition, AGRM member organizations operate rehabilitation programs for drug addicts and alcoholics, provide assistance to the elderly poor and at-risk youth. If annual cash contributions to all member missions were combined, the Association would be among the ten largest nonprofit organizations in the United States; each year, AGRM's network of some 300 rescue missions serve 66 million meals, provide more than 20 million nights of shelter and housing, assist some 45,000 people in finding employment, provide clothing to more than 750,000 people, graduate nearly 17,000 homeless men and women from addiction recovery programs into productive living. Rescue missions have been providing hospitality to impoverished people in America since the 1870s.
Rescue mission staff members provide effective care for men and children who are hungry, abused, or addicted. AGRM is North America's largest network of crisis shelters and rehabilitation centers. Jerry and Maria McAuley founded a rescue mission in October 1872, which became a precursor of a ministry, to spread around the world; the rescue mission would become the New York City Rescue Mission. Mission leaders saw a need for an organization that would foster “fellowship, cooperation with all engaged or interested in gospel missions, other rescue work throughout the United States and in other lands, in the mutual advancement of the cause of our Lord Jesus Christ.” The International Union of Gospel Missions was organized on September 1913, in New York City. Mr. Sidney Whittemore is credited as the father of the body; the State of New York granted the rescue ministry leaders a certificate of incorporation on October 14, 1913. As the IUGM grew, it devised a system of convenience for closer and more concentrated work among its members by establishing local branches known as districts.
Today there are nine districts. Rescue — Pulling people to safety from adverse conditions, from choices and habits that lead to damaged health and death Redemption — Presenting people with a gospel, about life transformation in Jesus, the reclamation of His creation Rehabilitation — Helping people break the bonds of addiction and desperate behavior, experience a life of healing and wholeness Re-assimilation — Preparing people to dwell in community, to have meaningful roles that lead to stability and missional living As part of its mission, AGRM takes four major responsibilities: Creating new rescue mission ministries; the Association of Gospel Rescue Missions is responsible for aiding missions of homeless people and others in need every year. In 2010 alone, the association graduated more than 18,000 homeless men and women from its programs into productive living, distributed more than 24 million pieces of clothing, provided some 210,000 families with 735,000 items of furniture–along with offering millions of meals and nights of lodging.
AGRM welcomes both organizational memberships. City Mission City Vision College, online college founded in 1998 by AGRM as "Rescue College".
The Rihand River is a tributary of the Son River and flows through the Indian states of Chhattisgarh and Uttar Pradesh. Its old name was Renuka; the Rihand rises from Matiranga hills, in the region south west of the Mainpat plateau, about 1,100 meters above mean sea level. The river flows north through the central part of Surguja district for 160 kilometres; the Rihand and its tributaries form a fertile plain in the central part of the district stretching from its origin to Lakhanpur, Pratappur. Thereafter, it flows north into Sonbhadra district of Uttar Pradesh via Singrauli district of Madhya Pradesh, where it is called Rhed and joins the Son, it is principal tributaries in Surguja district are the Mahan, the Morana, the Geur, the Gagar, the Gobri, the Piparkachar, the Ramdia and the Galphulla. Many seasonal and perennial rivers join the Rihand reservoir such as the Kanchan, the Mayar and the Azir of Singrauli district of Madhya Pradesh; the Rihand Dam was constructed across the Rihand River near Pipri in Sonbhadra district of Mirzapur division in 1962 for hydropower generation.
Nearest railway station is Renukoot. Rihand River has a fall named'Rakasganda', in its journey in Surajpur district of Chhatishgarh; this fall is important for tourist point of view. List of rivers in India Tourism in Chhattisgarh