Lava lake

Lava lakes are large volumes of molten lava, usually basaltic, contained in a volcanic vent, crater, or broad depression. The term is used to describe both lava lakes that are wholly or partly molten and those that are solidified (sometimes referred to as frozen lava lakes in this case).

Formation

Lava lakes can form in three ways:

Behaviors

Lava lakes occur in a variety of volcanic systems, ranging from the basaltic Erta Ale lake in Ethiopia and the basaltic andesite volcano of Villarrica, Chile, to the unique phonolitic lava lake at Mt. Erebus, Antarctica. Lava lakes have been observed to exhibit a range of behaviours. A “constantly circulating, apparently steady-state” lava lake was observed during the 1969–1971 Mauna Ulu eruption of Kilauea, Hawaii. By contrast, a lava lake at the 1983–1984 Pu'u 'O'o eruption of Kilauea displayed cyclic behaviour with a period of 5–20 minutes; gas “pierced the surface” of the lake, and the lava rapidly drained back down the conduit before the onset of a new phase of lake activity. The behaviour observed is influenced by the combined effects of pressure within the reservoir, exsolution and decompression of gas bubbles within the conduit and, potentially, exsolution of bubbles within the magma reservoir. Superimposed upon this is the effect of bubbles rising through the liquid, and coalescence of bubbles within the conduit. The interactions of these effects can create either a steady-state recirculating lake, or a lake level that periodically rises and then falls.

Lava Lake

Lava Lake is a lava dammed lake located in northwestern British Columbia, Canada. The lake lies within the Nisga'a Memorial Lava Beds Provincial Park, which includes fishing, hiking and other features.

Formation

Lava Lake formed when lava flowed into the Tseax River in the 18th century, damming it to form Lava Lake. The flow subsequently traveled 11 km (7 mi) north to the Nass River, where it filled the flat valley floor for an additional 10 km (6 mi), making the entire lava flow approximately 22.5 km (14 mi) long. This is one of Canada's youngest lava flows. The source for this lava was the Tseax Cone.

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Lake

A lake is an area of variable size filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean (except for sea lochs in Scotland and Ireland), and therefore are distinct from lagoons, and are also larger and deeper than ponds, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which are usually flowing. However most lakes are fed and drained by rivers and streams.

Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers. In some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.

Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic or recreational purposes.

Pigment

A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.

Many materials selectively absorb certain wavelengths of light. Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tinting strength relative to the materials it colors. It must be stable in solid form at ambient temperatures.

For industrial applications, as well as in the arts, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade over time, or with exposure to light, while some eventually blacken.

Pigments are used for coloring paint, ink, plastic, fabric, cosmetics, food, and other materials. Most pigments used in manufacturing and the visual arts are dry colorants, usually ground into a fine powder. This powder is added to a binder (or vehicle), a relatively neutral or colorless material that suspends the pigment and gives the paint its adhesion.

Lake (disambiguation)

Lake or lakes may refer to:

People

Places

Entertainment and media

Lava

Lava is the molten rock expelled by a volcano during an eruption. The resulting rock after solidification and cooling is also called lava. The molten rock is formed in the interior of some planets, including Earth, and some of their satellites. The source of the heat that melts the rock within the earth is geothermal energy. When first erupted from a volcanic vent, lava is a liquid at temperatures from 700 to 1,200 °C (1,292 to 2,192 °F).

A lava flow is a moving outpouring of lava, which is created during a non-explosive effusive eruption. When it has stopped moving, lava solidifies to form igneous rock. The term lava flow is commonly 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, and is probably derived from the Latin word labes which means a fall or slide. The first use in connection with extruded magma (molten rock below the Earth's surface) was apparently in a short account written by Francesco Serao on the eruption of Vesuvius between May 14 and June 4, 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.

Lava (2001 film)

Lava is a 2001 British black comedy directed by Joe Tucker.

The film competed at the Alexandria International Film Festival, Filmfest Oldenburg, Austin Film Festival and Rome Independent Film Festival in 2000.

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