Showing posts with label rocks. Show all posts
Showing posts with label rocks. Show all posts

June 7, 2008

Pamukkale

PamukkaleFrom 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.

May 16, 2008

Balancing Rocks

Balancing Rocks


















With a history that stretches back 3 and half billion years, the enormous formations that make up the Balancing Rocks are the one among the oldest wonders on the planet. The rocks appear to be so precariously balanced, one on top of another, that even a light push could send them rolling down into the surrounding scrub. But as the thoushands of tourists who have tried can testify, no shove can dislodge the Balancing Rocks. They sway, but they never fall.

How do these rocks balance? Time, Climate, erosion and the structure of the rock give the answers. The rocks were once part of the earth's crust. The crust is mainly granite, which originally lay molten deep within the earth. Over millennia it gradually rose toward the surface, cooled, shrank, and cracked in such a way as to produce a series of massive granite blocks that were more or less rectangular. As time passed, groundwater seeping in through the cracks weathered these blocks and eventually rounded off the once angular corners. After the rocks became exposed on the surface of the land, the sun, wind and rain completed the rounding-off process. Daily heating and cooling helped flake off the surface layers already loosened by water, wind and rain carried away the debris. Thus, once-solid mass of granite has eroded into a heap of giant boulders, some poised at such delicate angles that a hand can rock but never dislodge them.