Kuckersite
Kuckersit or Kukersit (after the village Kukruse , dt. Kuckers ) is a red-brown sedimentary rock from the Ordovician of Estonia and northwestern Russia , which is combustible due to its high oil content and is counted among the oil shale . It forms the basis of a significant industry in Estonia.
The term "Kuckersite" was first used by Mikhail Dmitrijewitsch Salesski in 1916 , before the rock was called "Kucker's layer" and "Kucker's fire slate ".
Rock description
Kuckersite is a schisty , predominantly fine-grained rock of light to dark brown color. In places, it is rich in visible to the naked eye fossils ( ostracods (Ostrakoda) and bryozoans (Bryozoa)). Under the light microscope it can be seen that it consists largely of organic structures. In some places, irregular black lenses of asphalt minerals can be seen. The rock is rich in oil, the oil content can make up to 46% of the rock and is therefore one of the highest oil contents in oil shale worldwide. In addition to organic substances, there are silicates and aluminosilicates as well as a high lime content for an oil shale. In contrast to the similar Ordovician Dictyonema schists that are common in northern Estonia and Sweden, the heavy metal content of the cuckoo site is low. The formation of the rock changes, and limestone layers and nodules occur within the rock.
Emergence
In the Ordovician, large parts of the continental area were flooded. In Central and Northern Europe, limescale deposits formed in shallow seas, including in the Baltic States . In the area of today's Kuckersit large amounts of blue-green algae of the species Gloeocapsomorpha prisca were deposited in the shallow sea, a marine Gyttja formed . On the basis of comparisons with similar modern deposits, a depth of no more than four meters is assumed for the sea area in which the cuckersite originated.
Occurrence
Kuckersite occurs extensively on the eastern tip of the Gulf of Finland as a frequently repeated interposition in limestones of the Kõrgekallas and Viivikonna Formations of the Middle Ordovician of Estonia and Russia. In these 20 to 30 m thick limestone series, up to 50 individual layers of cuckersite and cuckersite-like rocks were counted, which are a few centimeters to a maximum of two to three meters thick . Above the in the lower part of this sequence in Estonia and Russia disrupted Main occurrence that most of the mining operations pulls up, exist in the upper part of the sequence, the so-called tapa-bearing which mainly south of Tapa found in Estonia.
The rock is exposed over more than 90 kilometers from Tallinn to Saint Petersburg , the area of its distribution area is more than 50,000 km 2 . The rock layers dip flat to the southwest and have been proven by drilling up to about 60 kilometers south of the coast. Total stocks in Estonia are estimated at around 6 to 21 billion tons, depending on the source.
use
The oil shale had long been known to the inhabitants of the Gulf of Finland and was used by them as fuel. Scientific research began in 1697 with a sample sent to Holland by Peter I for examination. The results of the investigations were not published until the beginning of the 19th century. Johann Gottlieb Georgi described the rock in his text Geographical-Physical and Natural-Historical Description of the Russian Empire, published in Königsberg from 1791–1798, to provide an overview of previous knowledge of the same type .
First attempts at large-scale mining began in the 1880s in the Kukruse area; industrial mining did not take place in Russia until 1916. The first large plant for the extraction of oil from kuckersite was put into operation in Kohtla-Järve in 1924 . Up until 1940, diesel fuel and lubricants were primarily produced, as well as wood preservatives and bitumen from shale oil. At that time, almost 10% of Estonian export earnings were made from shale oil.
Today, Kuckersit covers 62% of Estonia's oil needs and is particularly important in the field of energy supply. The oil extraction from the mined kuckersite takes place in so-called Kiviter retorts and Galoter retorts . Kuckersite is also used in power generation , in the building materials and chemical industries.
The extraction takes place today in the east of the country in the area of Kohtla-Järve and Narva by the company Eesti Põlevkivi , at the end of the 1990s there were still six mines up to 80 m deep and four open-cast mines . Larger deposits have been found to the west of Kohtla-Järve in particular, but have not yet been mined (as of 1999). Today the extraction and use of cuckersite in Estonia is just about competitive with the production of energy from natural gas or coal, and an exhaustion of the supplies is foreseeable. The industrial mining of kuckersite has given rise to major environmental problems that still burden the mining regions severely today.
Kuckersite has also been mined in Russia, but not as much as in Estonia. Even today there are still mining sites between St. Petersburg and the Estonian border.
Individual evidence
- ^ Hans Murawski, Wilhelm Meyer: Geological dictionary . Ferd. Enke Verlag Stuttgart, 11th edition 2004, 262 pages, ISBN 978-3-8274-1445-8 .
- ↑ a b c Robert v. Kesling: Notes on two Ordovician Ostracods from Estonia. Contributions from the Museum of Paleontology, University of Michigan, Vol. XII, No. 13. pp. 259-272, 1955 ( PDF, 790 kB ).
- ↑ a b c d e Stefan Porath: Production of chemical raw materials from kukersite by pyrolysis. Dissertation to obtain a doctorate from the chemistry department of the University of Hamburg, 128 p., 1999 .
- ^ A b c John R. Dyni: Geology and resources of some world oil-shale deposits. Scientific Investigations Report 2005-5294 . (PDF) In: US Department of the Interior. US Geological Survey . 2006. Retrieved August 27, 2007.
- ↑ a b K. Luts: Esthonian Oil Shale - Its Chemistry, Technology, and Analysis. Chapter I. The Kukersit. Revaler Buchverlag GmbH, 29 p., Reval 1944. ( PDF, 5.4 MB ( Memento from September 10, 2008 in the Internet Archive )).
- ↑ NE Altun, C. Hiçyılmaz, JY Hwang, A. Suat Bağci, MV Kök: Oil Shales in the world and Turkey; Reserves, current situation and future prospects: a review . (PDF) In: Estonian Academy Publishers (Ed.): Oil Shale. A Scientific-Technical Journal . 23, No. 3, 2006, ISSN 0208-189X , pp. 211-227. Retrieved August 27, 2008.
- ↑ a b Day 04 - 13.09.05: Võsu - Kohtla-Järve - Narva - Endla National Park. ( Memento from September 10, 2008 in the Internet Archive ) Geographical Institute of the Ruhr University Bochum, documents for the excursion to Estonia 2005.