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Ga;siorowski M.,Polish Academy of Sciences | Hercman H.,Polish Academy of Sciences | Ridush B.,Chernivtsi National University | Ridush B.,Ukrainian Institute of Speleology and Karstology | Stefaniak K.,Wroclaw University
Quaternary International

The Crimean Peninsula is an extraordinary region located on the border between Europe and Asia. Its location made it an important refuge for migratory animals during the entire Pleistocene. The red deer (Cervus elaphus) was one of the most abundant species among large herbivores in the Crimean region. Its numerous remains were found in several cave sites, including the Emine-Bair-Khosar Cave. The bone-bearing sediments in the cave were deposited from MIS 3 to the beginning of the Holocene, with a significant hiatus during the Last Glacial Maximum (LGM). These two facts made it possible to reconstruct the climate changes and plant succession during the last 40,000 years. To recognise these processes, we studied the isotopic composition of carbon and nitrogen of collagen from red deer bones deposited in this trap cave. At the beginning, the δ15Ncoll values varied widely, suggesting a relatively high proportion of grass in the red deer diet. The high 15N concentrations were correlated with relatively high δ13Ccoll values. This part of the sequence was probably deposited during a relatively warm and dry period (MIS 3) when steppe was the dominant vegetation type. Later, the δ15Ncoll values decreased significantly and the δ13Ccoll remained basically unchanged. The prominent decrease in the soil activity suggests a climate deterioration and tundra development during MIS 2, before the Last Glacial Maximum (LGM). After LGM, during the Late Glacial, the δ13Ccoll declined and the δ15Ncoll significantly increased, reflecting milder climate conditions and, probably, spread of forest near the cave. © 2013 Elsevier Ltd and INQUA. Source

Ridush B.,Chernivtsi National University | Ridush B.,Ukrainian Institute of Speleology and Karstology | Stefaniak K.,Wroclaw University | Socha P.,Wroclaw University | And 4 more authors.
Quaternary International

The Crimean Mountains are well known from the abundance of Middle and Late Palaeolithic sites and palaeontological remains recovered from cultural layers in caves and rockshelters. The fossil-bearing deposits of Emine-Bair-Khosar Cave, located at the elevation of 1000 m on the Chatyrdag Plateau, yielded a very diverse and numerous vertebrate remains that widen the knowledge of Late Pleistocene faunal diversity in the Crimea. The assemblage comprised in total almost 50 species of vertebrates. Studies included geomorphological, geological and stratigraphic analyses as well AMS 14C dating. Faunal remains were present in ten palaeontological sites. The main bone accumulation (section Ba2) was deposited during Middle Valdai or Vytachiv (MIS 3) interstadial, and including a long time gap, to the end of the Pleistocene and the Holocene. Comparison of the Emine-Bair-Khosar fauna with vertebrate faunas of other Crimean sites showed a remarkable stability in the faunal composition and frequency during the whole MIS 3 interstadial. Steppe and other open-country species dominated in the compared assemblages, while boreal-tundra species were far less numerous. Inhabitants of forests, including red deer and some rodents, were stable members of fossil assemblages. © 2012 Elsevier Ltd and INQUA. Source

Klimchouk A.,Ukrainian Institute of Speleology and Karstology | Tymokhina E.,Ukrainian Institute of Speleology and Karstology | Amelichev G.,Ukrainian Institute of Speleology and Karstology
International Journal of Speleology

In carbonate rocks, especially in those with high primary porosity such as most Cenozoic carbonates, the interaction between deeply derived rising flow through sub-vertical fracture-controlled conduits and intrastratal matrix flow of shallower systems can invoke mixing corrosion and result in prominent speleogenetic effects. This paper outlines a conceptual model of such interaction and provides instructive field examples of relevant morphological effects from two different regions within the Prichernomorsky (north Black Sea) basin, where karst features are developed in lower Pliocene, Eocene and Paleocene limestones. In the Crimean fore-mountain region, extensive steep to vertical limestone scarps formed through recent exposure of hypogenic fracture-controlled conduits provide outstanding possibilities to directly examine details of the original karstic porosity. The morphological effects of the conduit/matrix interaction, documented in both caves and exposed scarps, include lateral widening of sub-vertical conduits within the interaction intervals (formation of lateral notches and niches) and the development of side bedding-parallel conduits, pockets and vuggy-spongework zones. Natural convection circulation, invoked by interaction of the two flow systems, spreads the morphological effects throughout the conduit space above the interaction interval. Where the interaction of the two flow systems is particularly strongly localized, such as along junctions of two vertical fracture sets, the resultant morphological effect can take the form of isolated chambers. The variety of speleogenetic features developed through the conduit/matrix interaction, can be broadly grouped into two categories: 1) variously shaped swells of the major fracture conduit itself (morphological features of its walls - niches and pockets), and 2) features of the vuggy-spongework halo surrounding the conduit. This halo includes clustered and stratiform cavities, spongework zones and lateral side conduits. The speleogenetic features due to conduit/matrix flow interaction, especially the halo forms, often demonstrate distinct asymmetry between opposite walls of the conduits. The prominent phenomenon of the vuggy-spongework halo around fracture-controlled conduits has important hydrogeological implications. A comparison of karst features in different regions and rock formations clearly shows that in spite of some distinctions imposed by local structural, sedimentological and paleo-hydrogeological peculiarities, hypogenic speleoforms in limestones of different age and of different degree of diagenetic maturity demonstrate remarkable similarities. Source

Dublyansky Y.V.,University of Innsbruck | Klimchouk A.B.,Ukrainian Institute of Speleology and Karstology | Spotl C.,University of Innsbruck | Timokhina E.I.,Ukrainian Institute of Speleology and Karstology | Amelichev G.N.,Ukrainian Institute of Speleology and Karstology
Chemical Geology

Although it is commonly perceived that isotopic alteration of carbonate rock is suppressed at low temperatures (below ca. 80-100. °C), this study demonstrates that alteration halos do develop in permeable limestones of relatively low textural maturity. The study of Paleogene carbonate bedrock constituting the walls of hypogene karst conduits of the Crimean Piedmont (Ukraine) revealed several events of water-rock interaction, each resulting in isotopic alteration of the bedrock.Early development of hypogene karst conduits shifted δ18O and δ13C toward lower values by 1-2‰ and 1-3‰, respectively. The width of the alteration zone locally exceeds several meters. The case hardening associated with cavernous weathering shifted δ18O and δ13C of the bedrock toward slightly more positive values (by up to 3‰ and 1‰, respectively). The thickness of isotopic halos ranges from a few centimeters to tens of centimeters. During late-stage hypogene karstification the δ18O values of the bedrock was shifted toward lower values (by 5-6‰), forming a thin (5-15mm) alteration halo. In most cases δ13C was also shifted toward lower values (by 6-9‰), but in one case a shift toward higher values (by ca. 2‰) was observed.Water involved in early hypogene karst and in the origin of cavernous weathering structures was enriched in 18O{cyrillic}. Such waters are known in Crimea in association with mud volcanoes on the Kerch Peninsula. We suggest that similar deep-seated water affected the Crimean Piedmont during the Middle Miocene. Water involved in late hypogene karstification had δD values of -75 to -68‰ and δ18O values of -10 to -9‰ (fluid inclusion data), similar to present-day spring and well water in Crimea. Isotopic calculations and fluid-inclusion data indicate that the late hypogene karst processes occurred at low temperatures ( Source

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