Capitol - Washington, DC

The United States Capitol in Washington, D.C., is among the most architecturally impressive and symbolically important buildings in the world. It has housed the meeting chambers of the Senate and the House of Representatives for almost two centuries. Begun in 1793, the Capitol has been built, burnt, rebuilt, extended, and restored; today, it stands as a monument not only to its builders but also to the American people and their government.

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Source: http://www.aoc.gov/cc/capitol/index.cfm

Abyss

The abyssal zone is the pelagic zone that contains the very deep benthic communities near the bottom of oceans. Abyss is from the Greek word meaning bottomless sea. At depths of 4,000 to 6,000 meters (13,123 to 19,685 feet), this zone remains in perpetual darkness and never receives daylight. Its permanent inhabitants – for example, the Black swollower, tripod fish, deep-sea anglerfish, and the giant squid – are able to withstand the immense pressures of the ocean depths, up to 775 kg per square centimeter (76 MPa). Many abyssal creatures have underslung jaws to sift through the sand to catch food. The deep trenches or fissures that plunge down thousands of feet below the ocean floor – for example, the midoceanic trenches such as the Marina Trench in the Pacific – are almost unexplored. Only the bathyscaph Trieste has been able to descend to these depths. These regions are also characterized by continuous cold and lack of nutrients. The abyssal zone has temperatures around 2 to 3 degrees Celsius.
The area below the abyssal zone is the hadal zone and hardly any living creatures inhabit it. The zone above is the bathyal zone, and above that is the photic zone, in which the majority of ocean life exists.

Sorce: http://en.wikipedia.org/

Peak - Luray Caverns

For more than 125 years, Luray Caverns has been renowned as a spectacular natural wonder. Today the caverns remain as magical and majestic as when they were first discovered in 1878 by a tinsmith and a local photographer. Millions of visitors have wandered the subterranean pathways and discovered for themselves the natural draw of Luray Caverns.

Begining of the Shenandoha Valley
During the continental drift about 600 million years ago, the Americas separated from the continents of Europe and Africa. A broad, shallow depression from Alabama north to Newfoundland was formed. Then, for 400 million years an ancient sea flooded the area that is now the Appalachian Mountains. Layers of water-borne sediments accumulated on the ocean floor, followed by limestone sediments composed of fossilized marine animals and shells. The weight of the sediments eventually compressed the two layers into metamorphic rock. As a result of the eons-old shifting of the earth's tectonic, or crystal, plates, North America and Africa collided. This elevated and fractured the sea floor, causing the older, underlying layer of metamorphic rock to tilt upward and slide over the younger layer, creating a towering mountain range, the Appalachians.

Growth of Formations
As the large volumes of water drained away, nature began crafting the stone formations left in the caverns today. Inside a cave created by the shifting earth, a solution of calcium carbonate gave up some of its carbon dioxide, allowing a precipitation of lime to form. This precipitation began as a thin deposit ring of crystallized calcite, but continued to collect, creating stalactites that hung from the ceiling. As water drops flowed down these deposits and fell to the floor, deposits built upwards, forming stalagmites. When a stalactite growing down from the ceiling met a stalagmite growing up from the floor, a column or pillar was formed. The growth process, also called dripstone, continues in Luray Caverns. Ours is an active cave where new deposits accumulate at the rate of one cubic inch every 120 years.

The Formations
Stalactites are often formed in a fluted and uniformed fashion from the ceiling down. Stalagmites, too, build with distinct mounds and ridges on their way toward the ceiling. Dripstone, in addition to covering the ceilings and floors, is also abundant on cavern walls. Sometimes dripstone results in massive decorations called flowstone, when mineral-bearing water spreads over limestone walls or builds its deposits from a protruding edge. These crystalline deposits can form draperies and stone waterfall formations.

There are many factors that can impact the shape and color of formations, including the rate and direction of the seepage, the amount of acid in the water, the temperature and humidity content of a cave, air currents, the above ground climate, the amount of annual rainfall and the density of the plant cover.

All coloration in Luray Caverns is natural, caused by different minerals in the seeping ground water. White is the color of calcium carbonate in its pure form. Other elements absorbed from the soil and rock layers create impure forms of calcite. Reds and yellows are caused by iron and iron-stained clays, black is the result of manganese dioxide, and blues and greens are the result of solutions of copper minerals.

Source:http://www.luraycaverns.com