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GEOLOGY ON POST STAMPS |
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GEOLOGY ON POST STAMPS |
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Bułgaria / Bulgaria
Wapienne grzbiety Ritlite wypreparowane przez erozję z miększych skał
marglistych, Ljutibrod.
Limestone vertical
beds called Ritlite, eroded from the marly surrounding rocks, Lyutibrod.
Coll. Grzegorz Barczyk
Ritlite (The Racks)
The protected area "Ritlite" is situated in the southern part of the Fore-Balkan (ca. 50 km ENE of Sofia). In the region, Paleozoic and Mesozoic rocks crop out, subdivided in many lithostratigraphical units. Many faults and folds complicate the geological structure of the area. The Racks are one of the most famous geological phenomena in Bulgaria. This is due to their unique beauty and their location in the very interesting Iskar Gorge, as well as the easy access and the possibility for travelling passengers to observe the features by train or by car.
From: http://www.gsi.ie/everyone/europe/bulgaria/bulgaria.htm
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Lyutibrod and Ritlite
These are rocky formations (a natural phenomenon) in the Iskar Gorge near
the village of Lyutibrod in the shape of parallel stone walls. Their height
is 60-80 m by the left bank of the Iskar River and gradually increases up to
200 m to the west. Their length is 200-500 m.
The western wall is 2,6 m thick. East of it is the
second wall (which is 6.5 m thick and is sitauated at a distance of 40 m). The
third wall is 6,5 m thick and is sitauated at a distance of 5 m. In ancient
times the Roman fortress wall at Ritlite blocked the exit of the Iskar Gorge and
was destroyed later. Ritlite are visited by mountain climbers and alpinists. The
Cherepishki monastery, the place of Rashov Dol, the ruins of the middle
centuries town of Koritengrad and the hill of Shishmanitsa are near there.
From: http://www.visit.vratza.com/index.php?lang=fr&r=ritlite&title=Lutibrod+et+Ritli
Sediments from the upper parts of the Urgonian complex (Vratsa Urgonian
Group, Lyutibrod Formation) are exposed. The Lyutibrod Formation (Lower
Cretaceous, Lower Aptian) is built up of detritic, oolithic, orbitolina-bearing
and other limestones in alternation with terrigeneous-carbonatic
packets(interbedding sandy limestones, calcareous sandstones and marls).Its
sediments are typical of the external carbonate platform or marginal
environments.Tempestites are often present in the section. Detailed observations
prove the presence of retrogradational and progradational tendencies and
sequences.In combination they form 3rd order sequences with eustatic genesis.
Both the limestones and marls contain abundant and various fossils (bivalves,
gastropods, corals, brachiopods and orbitolinas, the latter being rock-forming
in some levels).
The Urgonian complex along the Iskur valley between the Cherepish Monastery and
Lyutibrod is near the boundary between two tectonic units: the West-Balkan and
the Central-Balkan – Fore-Balkan ones. The boundary between them has a thrust
or upthrust character. Consequently, the packets of the Lyutibrod Formation are
in an upright position, the soft (marly or terrigeneous-carbonate) rock
intervals are eroded, and the vertical limestone packets form the natural
phenomenon "Ritlite".
From: http://www.geology.bas.bg/32igc/FTB26SecondDay.html
