About one third of Turkey is underlain by carbonate rocks. The intense karstification is spread almost all over Turkey. It is found particularly in the regions of the Taurus Mountain Range, in Northwest Anatolia, in Konya closed basin and in Southeastern Anatolia. Karstification is present both at high altitudes (over 2000 m.) and also it is known to exist at elevations below the sea level, such as Ovacik submarine springs, Kas - Kalkan submarine springs and the Mediterranean region coastal springs.

Turkey is thoroughly located in the Mediterranean sector of the Alpine organic belt. The Alpine orogeny and the following epirogenic movements in Turkey have been important factors in karstification.

According to Eroskay and Günay (1979), four karst regions can be differentiated in Turkey Taurus region, Central Anatolia region Southern Anatolia region, and Northwest Anatolia and Thrace region.

TAURUS REGION: This is the most important and largest karst region in Turkey. Taurus mountain ridges can be identified as the Alp's extension in Anatolia. It begins at the Aegean coast, continues through northeast of the Mediterranean sea to Iran and over eastern Anatolia. In this region between the Mediterranean coast and central Anatolia the width of carbonate units is mostly 200 km along the Taurus mountains, and the peaks of the sharp limestone hills are as high as 2500-3000 meters. The stratigraphy of the region contains different units from Cambrian to recent age. There are some parotocton metamorphits. Mesozoic limestones and dolomites occur in over 1000 m. thick layers. The evolution of the ophiolitic melange in the Late Cretaceous exists as an impervious base or cover according to the stratigraphical and structural position of the carbonate units. Important caves mostly exist along these contact lines.

CENTRAL ANATOLIA REGION: Central Anatolian region, which is located in the north of Taurus belt, seems a typical closed basin, morphologically bounded with high mountains. The average elevation is around 1200 m. The recrystallized hard limestones of Jurassic and Crataceous age, which bounded the basin on the south and west, are the extension of Taurus. The ophiolite settlement in the late Crataceous overlies the older carbonate units. The Neogene units, which cover large areas in the basin, are mostly on ophiolitic basement. Sometimes they are in contact with older limestones. Neogene limestone is locally called as Obruk limestone. The collapsed dolines in the basin which are called obruk, are the typical karst features.

SOUTHEAST ANATOLIA REGION: Considering the regional geology at the south of the Taurus belt, marginal folds and stable platforms units have been differentiated. In the marginal folds belt, karst has been developed mostly in the Midyat limestone of Eocen age. Gercüs or older impervious units underlie the Midyat limestone, as Korudag uplift. Sometimes carbonates of Mardin group of Cretaceous age crop out. Stable platform units are located at the south of marginal folds. It is the typical plateau-shaped smooth area of southeast Anatolia. In these region, large caves like the Taurus belt are rare.

NORTHWEST ANATOLIA AND THRACE REGION : In these region, limestone blocks covers limited areas when compared with other regions. In the Thrace part, Eocen limestone which lies along the southern margin of Istranca massif, Aegean part, Permian- Mesozoic limestones which overlie the older metamorphic massifs and Western Black Sea part Jurassic-Cretaceous flysch formations are important karstic units.

Extracted from Günay - Eroskay (1979).

TURKISH CAVE RESEARCHED ASSOCIATION

"Turkish Cave Research Association" has been established on April 1964. Activities has been carried under basic principles and aims such as general research, classification, scientific studies and touristy visits. Between the years 1964 - 1980 while representation of Turkey has been made at the international speleology platforms, also research activities has been undertaken with the French, Italian and English. In the meantime, as the Association we have participated in the activities carried at Cennet, Cehennem, Insuyu, Narlikuyu, Damlatas and Yalandünya caves to be opened to tourism. After 1980, researches were made with more weight given to the sports side of caving. During this term, more than fifty caves have been taken under research, maps have been prepared and the majority of these researches and activities has been published in the Association's bulletin. Furthermore, these activities have been made public through the exhibitions and meeting, conferences and with this aim, together with the Turkish Radio Television-TRT - Documentary of the Turkish Caves; Altinbesik, Indere, Tulumtas caves documentary programmes has been prepared. Right now, activities are being carried at the Central Taurus mountain region range.

DIRECTORATE OF THE INSTITUTE OF MINERAL RESEARCH

The Cave Research Project, operating since 1979 under the Directorate of the Institute of Mineral Research (M.T.A.), has completed the study of 150 caves of various sizes, despite shortages in personnel and equipment. The goal of the project is to determine the economical potential of caves rather than discovering the largest ones. The other aim is to form an inventory of Turkish caves. In accordance with the goals mentioned above, most of the research is concentrated in touristy areas or in karstic regions affected by water shortage.

BOSPHORUS UNIVERSITY, CAVE RESEARCH CLUB (BUMAK)

is a club formed by the students of the university. Activities are pursued on both sportive and scientific aspects of speleology for over 16 years. Though their study focuses mostly on the Zonguldak - Kastamonu region. They are also exploring and surveying caves in other regions of Turkey. Until now, over 80 unknown caves are explored.