This earthcache takes you to the amazing place in the SE of Istria Peninsula, Croatia. Vela Draga is a huge canyon under Ucka massif. It belongs to Ucka Nature Park.
Vela Draga - Geomorphological natural monument
Since 1963 vela Draga has been legally protected as a „natural area reserve“ and since 1968 as a geomorphological natural monument.
„The Vela Draga“ instructive path passes the edge of the impressive canyon of the same name and by means of interpretation boards makes the visitors familiar with this monument of an outstanding geomorphological value. The text of interpretation boards is written in a simple language meant for general public and explains the geological phenomena of the formation of the Ucka massif and the Vela Draga canyon itself.
Apart from geological phenomena the path provides information about alpinism and sports climbing, sports present in Vela Draga since 1931. With its impressive rocks and limestone towers up to 100 m high, including more than 60 well arranged climbing routes in a canyon surroudings, Vela Draga presents one of the most beautiful climbing grounds in Croatia.
The rocks of Ucka Mountain have been formed in the vast Tethys Ocean through a long geological time, from Cretaceous period 140 million zdar ago until mid Tertiary 30 million years ago. Endless and warm shallow marine waters were inhabited by numerous organisms protected by calcite or aragonite shells. Millions of years of settling of their skeleton remains have formed thick sediment layers which gradually, through compacting and cementing processes became solid rocks that we know under the name of limestone.
Collision of the African and European plates, which started by the end of the Cretaceous period 65 million years ago, and is still ongoing, has caused the Ocean shrinking, accompanied by intensive tectonic shifts. The originally horizontal layers settled into the Ocean‘s bottom, and then started creasing, cracking and raising above the sea, thus creating huge mountain chains such as the Alps and Dinara massif with Ucka as their part. Fine-grained sediment resulting from abrasion was periodically carried off into the sea depths by submarine avalanches, forming stratified rocks called flysch. So the former vastness of the Tothys was reduced to the sole area of the Mediterranean Sea. With current speed of continent movement of 2-3 cm per year, in some 50 million years even the Mediterranean could completely disappear due to the raising of its bottom into a new mountain chain.
After the raising of Ucka, which was the most intensive in the mid Tertiary, approximately 30 million years ago, the limestone in Vela Draga got exposed to atmospheric processes causing karstification – melting, abrasion and erosion which has been continuously forming the canyon ever since. Karstification gets even more intensive underground than on the surface, with water accumulating into strong currents that melt the rock and widen the cracks transforming them into cave passages. Such surface and underground karstification fragmentation along the fissures, aided with time, was the main sculptor of the canyon. Among other interesting sites, the canyon harbours a detailed story of fossil-rich limestone – the building material of the canyon – and a representation of surface erosion that is forming it still.
Coordinates will take you to the free parking place, where is also located the start point of the instructive path. Path lenght is 600m and it takes you about 30 minutes to go to the viewpoint and back to the parking spot. You will find answers to following questions on the information boards on the way to the viewpoint.
To get the log permission for this earthcache you have to answer the following questions and to do a task:
1) There are numerous remains of shells structuring the rock. What is the name of these shells?
2) What is the name of legendary traditional rock climber who is mentioned on one of the information boards?
3) Please, take a picture at the location (viewpoint), which may include either you, your GPS or some proof that you really reached the viewpoint and attach it to your log.
Please email me your answers (via GC-Profile) latest when you log this cache (you don't have to wait for a permission to log). If your answers are incorrect, I will inform you.
Logs and e-mail only in english please!
Text prepared by: Ramie Lackovic, B.Sc.Geology; Ph.D. Goran Susic