Seashells

A shell is a part of a sea creature known as mollusk. Mollusks are wormlike creatures and exist in the ocean, fresh water and also on land. The main characteristic of mollusks is that they dont have internal skeleton. Their shell serves as an exo-skeleton and protects them from the outside world. The shells are primarily composed of calcium carbonate, which is secreted by the outer surface of the mantle of the shell and are loosely attached to the animal body.

The food consumed by mollusk causes pigments to be produced within the mantle and based on this pigment secretion the outer shell's color and shapes are formed. If the pigment secretion is continuous, spiral or radial lines are formed. If the pigment secretion is periodic, then spots appear on the shell. When the mollusk dies, its shell is the one part that typically remains intact. Seashells are very often found in beach drift, which is deposited along strandlines on beaches.

Pamukkale

From a distance the fantastic rock formations of Pamukkale (meaning "cotton castle" in turkish) in southwestern Turkey resemble a castle built of snow and ice. Tier upon tier, the dazzling white ramparts and parapets descend for more than 300 feet down a rugged mountainside. On closer inspection, however, the steplike series of overlapping basins looks more like a gigantic waterfall petrified by some mysterious, awesome force of nature. The strange rocks of Pamukkale are the improbable handiwork of hot springs.

Farther up the mountainside springs bubble from the earth, issuing a stream of water with a temperature of about 43 degree celsius and very high concentration of dissolved mineral salts. The water has been flowing down the slope, cooling, evaporating, and depositing the dissolved minerals. Bit by bit, the walls of the many stepped rocky terraces and basins took their present form. For centuries the spring water has been prized for its therapeutic properties. In ancient times the Romans built a thermal resort, Hierapolis, nearby.

Strokkur

Ever since medieval times, Iceland has been famous for its many hot springs and geysers. Although the Geysir's performance has become less impressive in recent times, dozens of other hot springs continue to bubble and spurt in the same thermal area in southwestern Iceland. Amoung the most active and predictable in the group, located in a valley at the foot of a range of volcanic mountains, is Strokkur, the "churn". Every 4 to 10 minutes it shoots a jet of boiling water as high as 100 feet into the sky.

Fluctuations in the water level in its basin herald each eruption. As the turbulence increases, the surface of the water heaves up into a dome, then explodes into a cloumn of steam and water droplets. The clouds of vapour blow away on the breeze, but the water falls back to the basin to contribute to the next eruption. The abundance of geysers is due to Iceland's geological history. In this volcanically active zone, molten magama lies close to the earth's surface, where it heats underground water and powers its periodic eruptive escapes through fissures in the crust.

Eisriesenwelt

The mysteries of Eisriesenwelt were not discovered until 1879. Subsequent exploration revealed that the cave system extends over a total distance of some 26 miles (42 Kilometers). Eisriesenwelt - the "world of the ice giants" - is the largest ice cave in the world. Much of the interior of this cave system high in the Austrian Alps is filled with the fanciful forms of stalactites and stalagmites similar to those found in other caves. But here the contours seem to be more fluid and the colors more translucent. The reason is: The underground formations are composed not of minerals but of ice.
 
Since the temperature in the cave remains at or near freezing all year round, water dripping from the ceiling solidifies into immense icicles, similar to stalactites. Drops falling to the floor freeze, to form spirelike stalagmites. In some places ice stalactites and stalagmites have joined into large floor-to-ceiling fluted pillars. Currently about 200,000 tourists come here every year. The cave with its entrance perched 3,300 feet above the valley floor, is accessible by cable car. Beyond the entrance visitors discover an artfully illuminated, shimmering fantasyland of ice sculptures on a mammoth scale.