A new Silurian xiphosuran from Podolia, Ukraine, USSR

A single incomplete specimen of a xiphosuran, Pasternakevia podolica gen. et sp. nov., from the Ludlow Series of Podolia, Ukraine, USSR, is described. It has a smooth, spatulate carapace and rounded genal cornua. The opisthosoma bears nine free tergites (second to tenth); the first tergite is reduced and hidden beneath the carapace. The tergites have a broad axial region and small pleurae; the second tergite is hypertrophic. Telson and appendages are not preserved. P. podolica resembles Pseudoniscus Nieszkowski, 1859 and Cyamocephalus Currie, 1927; it is thus placed in the infraorder Pseudoniscina Eldredge, 1974, but certain characters are shared with the synziphosurines. It comes from the lagoonal deposits of the upper part of the Ustye Suite (Bagovytsa Horizon) where it occurred together with Baltoeurypterus tetragonophthalmus (Fischer, 1839)

Faunal dynamics across the Silurian-Devonian positive isotope excursions (δ13C, δ18O) in Podolia, Ukraine: Comparative analysis of the ireviken and klonk events

Two global isotopic events, the early Sheinwoodian (early Wenlock) and that at the Silurian-Devonian transition, have been comprehensively studied in representative carbonate successions at Kytayhorod and Dnistrove, respectively, in Podolia, Ukraine, to compare geochemistry and biotic changes related correspondingly to the Ireviken and Klonk events. These two large-scale isotope excursions reveal different regional ecosystem tendencies. The well-defined increasing trend across the Llandovery-Wenlock boundary in siliciclastic input, redox states and, supposedly, bioproductivity, was without strict correlative relations to the major 13C enrichment event. The environmental and biotic evolution was forced by eustatic sea-level fluctuations and two-step climate change toward a glaciation episode, but strongly modified by regional epeirogeny movements due to location near the mobile Teisseyre-TÖrnquist Fault Zone. Thus, the global early Sheinwoodian biogeochemical perturbation was of minor depositional significance in this epeiric sea, as in many other Laurussian domains. Conversely, the Podolian sedimentary record of the Klonk Event exhibits temporal links to the abrupt δ13C anomaly, overprinted by a tectonically driven deepening pulse in the crucial S-D boundary interval. This carbon cycling turnover was reflected in the regional carbonate crisis and cooling episodes, paired with a tendency towards eutrophication and recurrent oxygen deficiency, but also with major storms and possible upwelling. Faunal responses in both Podolian sections follow some characters of the Silurian pattern worldwide, as manifested by conodont changeover prior to the major early Sheinwoodian isotopic/climatic anomaly. This contrasts with the relative brachiopod and chitinozoan resistances in the course of the Ireviken Event. Also, during the Klonk Event, a moderate faunal turnover, both in benthic and pelagic groups, occurred only near the very beginning of the prolonged 13C-enriched timespan across the system boundary, possibly due to progressive dysoxia and temperature drop. The characters point to a peculiarity of the Klonk Event by comparison with the Silurian global events, and some similarity already to the succeeding Devonian transgressive/anoxic episodes

The Starunia collections in the Natural History Museum of the National Academy of Sciences of Ukraine in Lviv

In the Natural History Museum of the National Academy of Sciences of Ukraine in Lviv there is a collection of a famous Pleistocene mammoth and a woolly rhinoceros, the so-called “first rhinoceros” from Starunia. The mammoth and the first rhinoceros were found 102 years ago, on 5th October and 6th November, 1907, respectively, in a shaft of an ozokerite (earth wax) mine near Starunia village (the Eastern Carpathians). The discovery of large Pleistocene mammals in Starunia was a spectacular, worldfamous scientific event. Beside the mammoth and the rhinoceros, many specimens of Pleistocene flora and fauna from Starunia and other places of the Fore-Carpathian region are exhibited in the Lviv Natural History Museum

A new icriodontid conodont cluster with specific mesowear supports an alternative apparatus motion model for Icriodontidae

Increasing numbers of conodont discoveries with soft tissue preservation, natural assemblages and fused clusters of the hard tissue have strengthened the hypothesis regarding the function and mechanism of the conodont feeding apparatus. Exceptional fossil preservation serves as a solid basis for modern reconstructions of the conodont apparatus illustrating the complex interplay of the single apparatus elements. Reliable published models concern the ozarkodinid apparatus of Pennsylvanian and Early Triassic conodonts. Recognition of microwear and mammal-like occlusion, especially of platform elements belonging to individuals of the genus Idiognathodus, allows rotational closure to be interpreted as the crushing mechanism of ozarkodinid platform (P1) elements. Here we describe a new icriodontid conodont cluster of Caudicriodus woschmidti that consists of one pair of icriodontan (I) and 10 pairs of coniform (C1\ue2\u80\u935) elements, with I elements being preserved in interlocking position. The special kind of element arrangement within the fused cluster provides new insights into icriodontid apparatus reconstruction and notation of elements. However, orientation of coniform elements is limited to a certain degree by possible preservational bias. Four possible apparatus models are introduced and discussed. Recognition of specific wear on denticle tips of one of the icriodontan elements forms the basis for an alternative hypothesis of apparatus motion. Analysis of tip wear suggests a horizontal, slightly elliptical motion of opposed, antagonistically operating I elements. This is supported by similar tip wear from much better preserved, but isolated, elements of Middle Devonian icriodontids. More detailed interpretation of the masticatory movement will allow enhanced understanding of anatomical specifications, diet and palaeobiology of different euconodont groups

Lochkovian conodonts from Podolia, Ukraine, and their stratigraphic significance

In the Podolian Dniester Basin (southwestern Ukraine) the Lower Devonian marine deposits are represented by about 530 m thick continuous sequence of interlaminated carbonate and schale outcrops at several localities. Conodonts occur in most of the carbonate layers of the whole Lochkovian but are not abundant and their ramiform elements are mostly broken or lacking. Therefore, only the pectiniform, Pa elements of twenty five stratigraphically important conodont species occurring in the region are discussed and two new species, Caudicriodus schoenlaubi and Pandorinellina? parva are proposed. The hypothetical phyletic relationships within the main representatives of the icriodontid and spathognathodontid genera, Caudicriodus, Zieglerodina, and Pandorinellina? are traced. Comparison of the previously published and newly obtained data revealed discrepancies in the hitherto used interpretation of some of the conodont taxa and their stratigraphic ranges. Contrary to the earlier reports, Caudicriodus postwoschmidti does not occur in the lower Lochkovian but only in the middle part of the Chortkiv Formation, high above the Monograptus uniformis Zone. Based on new material and verification of the previous determinations, a modified scheme of the Lochkovian conodont zonation in Podolia is proposed. Conodont zones: Caudicriodus hesperius, C. transiens, C. postwoschmidti, C. serus, and ?Caudicriodus steinachensis are distinguished. The zones are correlated with conodont zonations in other regions—Barrandian, Cantabrian Mountains, Pyrenees, and Nevada. Biostratigraphy of the Siluro−Devonian transition and Lochkovian is integrated with the carbon isotope stratigraphy

Early Devonian scolecodonts from Podolia, Ukraine

One of the most fossiliferous and thickest sections of the marine Lower Devonian deposits was, for the first time investigated for the content of polychaete jaws (= scolecodonts). They are represented by elements of five genera and at least nine species but are not abundant and mostly fractured. Only a fraction of the specimens are sufficiently well preserved to allow genus and species-level identification. However, in some of them even the microstructure of the jaw wall can be observed. Over 90% of the determinable specimens are represented by the jaws of paulinitids which mostly belong to three species known from the Silurian of the Baltic region. Additionally, mochtyellids, atraktoprionids, skalenoprionids and, in the lower part of the sequence, polychaetaspids have been recorded. Two new species are established—Polychaetaspis kozlowskii sp. nov. and Atraktoprion podolicus sp. nov. Status of the genera Oenonites Hinde, 1879 and Kettnerites is discussed. Lectotype of the first is not determinable to the species level, while holotype of the type species of the second is probably missing and not determinable after the original illustration

Lithostratigraphical correlation of the Ordovician in the Bi3goraj-Narol area with deposits of the adjacent regions of the marginal zone of the East European Craton in Poland and Ukraine

Presented is an attempt to correlate the Ordovician formal lithostratigraphic units of the Biłgoraj-Narol area with their counterparts in the adjacent regions of the marginal zone of the East European Craton in the territories of Poland and Ukraine. The comparison embraces profiles of 8 structural units representing various palaeogeographical environments, with different structure and facies. They differ in degree of drilling status as well. In the area of Poland these are: the Baltic Basin, the Łysogóry Unit of the Holy Cross Mts and the Lublin area. In Ukraine the comparison embraced: the Lviv Basin, the Carpathian Foredeep, the substratum of the Carpathians and the Volhynia and Podolia. The paper does not deal with the isochronous deposits known from the substratum of the Warsaw Basin and the Podlasie-Brest Basi

A new Silurian xiphosuran from Podolia, Ukraine, USSR

Volume: 30Start Page: 537End Page: 54

ГЕОЛОГО-ПЕТРОФІЗИЧНА ХАРАКТЕРИСТИКА БАСЕЙНОВИХ ДРІБНОЗЕРНИСТИХ ПОРІД СИЛУРУ ПІВДЕННО-ЗАХІДНОЇ ОКРАЇНИ СХІДНО-ЄВРОПЕЙСЬКОЇ ПЛАТФОРМИ

The paper presents the results of studies of mineralogical-petrophysical, lithological-facies and petrophysical properties of marine deep-seated deposits of argillite and aleurolite fractions of Silurian rocks of the south-western margin of the East European Platform as a potential object for prospecting of shale gas and tight gas.Приведены результаты исследований минералого-петрографических, литолого-фациальных и петрофизических свойств морских глубоководных отложений аргиллитовой и алевролитовой фракций пород силура юго-восточной окраины Восточно-Европейской платформы как потенциального объекта для поиска сланцевого (shale gas) и плотного газа (tight gas). Наведено результати досліджень мінералого-петрографічних, літолого-фаціальних і петрофізичних властивостей морських глибоководних відкладів аргілітової та алевролітової фракцій порід силуру південно-західної окраїни Східно-Європейської платформи як потенційного об’єкту для пошуків сланцевого газу (shale gas) та щільного газу (tight gas).

Charakterystyka geologiczna i fizykochemiczna dolnopaleozoicznych osadów Wołynia i Podola (zachodnia Ukraina)

The 340 to 1102 m thick multi-facies sequence was deposited during the Silurian at the Volhyno-Podillya margin of the East European Platform. The open shelf facies bordered from the west by a barrier formed by reefs, bioherms, crinoids, or by banks of detrital sediments (at the boundary of the lagoon and the open sea). Lagoonal deposits are represented by thin intercalations of sedimentary dolomites, sometimes with intercalations of organogenic limestones, marls, argillites, gypsum and anhydrite. Within the open shelf and slope facies, marls, lumpy clayey limestones and argillites are prevailing. A zone of reefal buildups has a rather complicated and insufficiently investigated structure. The exclusively terrigenous deposits of the submerged part of the continental slope form the entire Silurian sequence in the central part of the L’viv Depression and in the Carpathian Foredeep. Open porosity of the Silurian argillites vary from 0.6 to 2.4% and they are almost impermeable (less than 0.001 μm2•10–3). Volume weight ranges between 2.64 and 2.8 g/cm3. Natural radioactivity of rocks varies from 9 to 18 mcR/hr, apparent electric resistance is 20–154 Ohmm, interval time of longitudinal waves spreading is 126–365 μcs/m. TOC content, determined in 21 samples using the thermal analysis, varies from 0.75 to 2.38%. The composition of volatiles of fluid inclusions and closed pores of argillites shows the predominance of methane (up to 100 vol. %). In deeper horizons, carbon dioxide, nitrogen and ethane (a few percent) appear.Zróżnicowane facjalnie utwory syluru, miąższości od 340 do 1102 m, były deponowane na wołyńsko-podolskiej krawędzi platformy wschodnioeuropejskiej. Bariera budowana przez rafy, biohermy i ławice materiału detrytycznego graniczyła na zachodzie z facjami otwartego szelfu. Na wschód od tej bariery, w lagunie, tworzyły się osady dolomitowe z przeławiceniami organogenicznych wapieni, margli, iłowców, gipsu i anhydrytu. Osady szelfu i skłonu są reprezentowane głównie przez margle i ilaste wapienie gruzełkowe oraz argility. Strefa bariery rafowej ma dość skomplikowaną i jeszcze niedostatecznie rozpoznaną budowę. Osady terygeniczne występują tylko w zanurzonym odcinku skłonu kontynentalnego w centralnej części depresji lwowskiej oraz w podłożu zapadliska przedkarpackiego. Efektywna porowatość argilitów sylurskich wynosi od 0,6 do 2,4% i są one prawie nieprzepuszczalne (mniej niż 0,001 μm2ּ10–3). Gęstość objętościowa waha się pomiędzy 2,64 i 2,8 g/cm3. Promieniotwórczość naturalna skał sięga od 9 do 18 mcR/h, a pozorna oporność właściwa wynosi 20–154 Ohmm, czas interwałowy rozchodzenia się fal podłużnych – 126–365 μcs/m. Zawartość TOC, określona w 21 próbkach z wykorzystaniem analizy termicznej, waha się od 0,75 do 2,38%. Skład substancji lotnych z inkluzji fluidalnych i zamkniętych porów w argilitach wykazuje dominację metanu (do 100% obj.). W głębszych horyzontach pojawiają się dwutlenek węgla, azot i etan (kilka procent)