[EN] The Dogger rocks are 1,88 hectares wide natural monument declared in 1952 and belongs to National Park Velka Fatra, situated at the begining of Trlenska valley. Natural monument consists of limestone rock walls, 5 – 20 metres high, exposed by natural erosion with folded benches of radiolarit, in which fossils of sea radiolarits are preserved. Allows study of the profile, composition and color of doggeric layers. This is a typical deep-sea development of the Middle Jurassic (Dogger) era, in a typical radiloarit´s development of Krížna nappe limestones. Rocks are interesting because of presence of underwater slip, so-called slumping. This was reinforced by diagenetic sedimentary layers, that were deformed due to gravity sliding on an inclined seabed slope. It is also possible to see the presence of folding fractures on the outcrop. Horizontal folds were subsequently covered with the overlying layers. The soil is sandy - loam, mixed with gravel, shalow with debris and protruding rocks.
RADIOLARIA – They are microscopic unicellular organisms with quartc shells. They are among the oldest animals on Earth, and axisted since Proterozoic period, almost two billions years ago Shells of dead radiolkaria sank to the sea bottoms and accumulated in thick layers. This created geologically significant sediments that rose to form continents in later orogenetic processes and changed into crystalline slate. The most widespread radiolaria rock is radiolarite.
RADIOLARITE – It is solid quartz rock formed from fossilized radiolaria.
The monument and its surroundings is being overgrown by forest, but is easily accessible from the instructive panel Dogger´s rocks on the road in the valley Trlenská. Just go through the bench creek and then footpath through the meadow into the forest.
To login this cache, it is needed to send me an email through my profile with answers to these questions:
1. Describe the structure of the rock block - thickness of the layers, the direction of folds.
2. Describe by your own words, how you think the rocks were exposed?
3. Estimate roughly distance between the coordinates and the road.
4. What is the altitude of this place?
Optional: Interesting photo from the spot will be delightful.
You can log in now. If not received within 3 days of e-mail with the answers needed to login, your log will have to be deleted as invalid!
Zdroj/Information sources:
http://sk.wikipedia.org/wiki/Dogerské_skaly
panel naucneho chodnika Vlkolinec