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PAMUKKALE
Pamukkale means "cotton
castle" in Turkish.The springs have been used as a spa since the second
century BC .The travertine features have their origins in the shifting
of a fault in the valley of the Menderes river (between here and
Denizli). As the fault shifted, very hot springs with a very high
mineral content (notably chalk) arose at this location. Apart from the
slightly radioactive minerals, the calcium and hydrogen carbonate react
to create calcium carbonate (also known as travertine) and limestone.
This is what gives Pamukkale it's whiteness and created the pools.You
can walk down barefooted in the waterfalls from the village on top. The
place is crowded when the tour-buses arrive. If you stay at one of the
small pensions they might give you a tour of the ruins and travertines
at night. It is worth seeing the remains of the ancient city of
Aphrodisias. You can rent a van from Denizli to get there. Or the local
hotels run tours for approx 25 lira. Also there are thermal baths at the
top of the travertine pools and the ancient city of Hierapolis with a
great Amphytheatre. Of moderate interest might be Denizli it's a bit
dull but there's a lively market. Loadikya is another less visited ruin
site only 10kms from Pamukkale on the local dolmus, entrace was free and
there was virtually NO tourists there. Peaceful way to spend a day
looking at ruins but also the beautiful scenery there as well.
The
sources of thermal water for Pamukkale are about 20 km from
Denizli.
The ancient city of Hierapolis is also located in the same place. The
water comes from underground karstic caverns and creates the cascades
through precipitation of CaCO3 (calcium bicarbonate ) as the CO2 (carbon
dioxide) evaporates. Thermal spring water is beneficial for myocardium
and cardiac complaints.The curative value of this thermal spring was
understood in ancient times as well. It has been used for centuries.
During the Roman Era religious ceremonies and festivals were held at the
thermal pools, and important statesmen and rich people came to
Hierapolis to be cured. Religious functionaries and ancient physicians
administered healing.
The
spring waters are rich in calcium, magnesium sulfate, bicarbonate and
carbon dioxide. They also have a radioactive content of 1,537
picocuries/liter. The pH is 6.0.
Travertine is a kind of rock which is formed as calcium bicarbonate
precipitates out of hot spring water. It may be formed in many ways
under different atmospheric conditions. Geological activity of the past
affected a large area in which the Pamukkale thermal springs are found.
There are 17 thermal sources in this special area with temperatures
ranging between 35-100°C. The source of Pamukkale is only one unit of
that whole area. The thermal water flows to the top of the cascades by a
320-meter-long channel and then flows on the cascades about 240-300 m.
CaCO3 begins to precipitate on the cascades as the carbon dioxide
evaporates, but in the beginning the precipitate is soft like gel. It
needs time to completely dry and harden. In order to protect the
cascades from destruction and to preserve their natural beauty, entrance
to the travertine area has been prohibited since 15 May 1997.
Weather
conditions, the temperature of the water, and sufficient time for water
to spread and flow are very important for the maintenance of white
travertines. Precipitation goes on until the levels of carbon dioxide in
the thermal water and the surrounding air are balanced. While the
quantity of CO2 is 725 mg/l in the source, it is only 125 mg/l at the
end of the travertines. Calcium bicarbonate also decreases from 1200
mg/l to 400 mg/l, and calcium decreases from 576 to 8 mg/l. Analysis
indicates that 499.9 mg of CaCO3 precipitates per liter of thermal water
over the cascades. The average density of the thermal water is 1.48
g/cm3 with a flow rate of 466.2 liters/second. That means 43,191 grams
of calcium bicarbonate precipitate from the thermal water per day.
Theoretically, that can whiten a 13,584 m2 area. However, whitening a
13,584 m2 area is practically very difficult. The whole travertine area
currently covers 22,000 m2.There is an area called ''Domuz Çukuru''
which is about 3000 m2 on an old street which used to be connected to
Pamukkale Town. It is free for tourists.
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