Quilotoa lake

Quilotoa (Spanish pronunciation: [kiloˈto.a]) is a water-filled caldera and the most western volcano in the Ecuadorian Andes. The 3 kilometres (2 mi) wide caldera was formed by the collapse of this dacite volcano following a catastrophic VEI-6 eruption about 800 years ago, which produced pyroclastic flows and lahars that reached the Pacific Ocean, and spread an airborne deposit of volcanic ash throughout the northern Andes. The caldera has since accumulated a 250 m (820 ft) deep crater lake, which has a greenish color as a result of dissolved minerals. Fumaroles are found on the lake floor and hot springs occur on the eastern flank of the volcano.

Quilotoa is a tourist site of growing popularity. The route to the "summit" (the small town of Quilotoa) is generally traveled by hired truck or bus from the town of Zumbahua 17 km to the South. Visitors must pay two US dollars each to look from the lip of the caldera. A number of simple hostales have developed in the immediate area, and offer services such as mules and guides for the five-hour hike around the caldera (whose diameter is about 9 km), a half-hour hike down (and 1-2 hour hike back up the 400 meter vertical ascent), and very basic lodging down in its bowl. Camping is permitted at the bottom of the crater, but there is no potable water (except half-liter bottles sold at the hostel), and only a single pit toilet, located in the hostel.

A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot magma, volcanic ash and gases to escape from below the surface.

Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust in the interiors of plates, e.g., in the East African Rift, the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America. This type of volcanism falls under the umbrella of "Plate hypothesis" volcanism. Volcanism away from plate boundaries has also 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.

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. 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.

A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters. The word comes from Spanish caldera, and this from Latin CALDARIA, meaning "cooking pot." In some texts the English term cauldron is also used.

In 1815, the German geologist Leopold von Buch visited the Las Cañadas caldera of Teide on Tenerife, and the Caldera de Taburiente on La Palma, both in the Canary Islands. When he published his memoirs he introduced the term caldera into the geological vocabulary.

A crater lake is a lake that forms in a volcanic crater or caldera, such as a maar; less commonly and with lower association to the term a lake may form in an impact crater caused by a meteorite. Sometimes lakes which form inside calderas are called caldera lakes, but often this distinction is not made. Crater lakes covering active (fumarolic) volcanic vents are sometimes known as volcanic lakes, and the water within them is often acidic, saturated with volcanic gases, and cloudy with a strong greenish color. Lakes located in dormant or extinct volcanoes tend to have fresh water, and the water clarity in such lakes can be exceptional due to the lack of inflowing streams and sediment.

Landscape comprises the visible features of an area of land, including the physical elements of landforms such as (ice-capped) mountains, hills, water bodies such as rivers, lakes, ponds and the sea, living elements of land cover including indigenous vegetation, human elements including different forms of land use, buildings and structures, and transitory elements such as lighting and weather conditions.

Combining both their physical origins and the cultural overlay of human presence, often created over millennia, landscapes reflect the living synthesis of people and place vital to local and national identity. Landscapes, their character and quality, help define the self image of a region, its sense of place that differentiates it from other regions. It is the dynamic backdrop to people’s lives.

The Earth has a vast range of landscapes including the icy landscapes of polar regions, mountainous landscapes, vast arid desert landscapes, islands and coastal landscapes, densely forested or wooded landscapes including past boreal forests and tropical rainforests, and agricultural landscapes of temperate and tropical regions.

Landscape photography is a genre intended to show different spaces within the world, sometimes vast and unending, but other times microscopic. This popular style of photography is practiced by professionals and amateurs alike. Photographs typically capture the presence of nature and are often free of man-made obstructions. Landscape photographers usually attempt not only to convey the documentary aspect, but also an appreciation of the scenery that is being photographed.