Deep in shadows, deep in time: the oldest mesophotic coral ecosystems from the Devonian of the Holy Cross Mountains (Poland)

This research was funded by the National Science Center of Poland, (decision No. DEC-2013/09/D/ST10/04058), a research Grant to MKZ. MKZ would like to express his sincere thanks to B. R. Rosen (London) for inspiring discussions, P. Muir (Townsville) for access to coral collections, S. Cairns (Washington), J. Stolarski (Warsaw) and N. Santodomingo (London) for information on azooxanthellates. M. Ginter (Warsaw) provided advice on the shark on the reconstruction figure. Mr. B. Waksmundzki (Warsaw) kindly drew reconstructions of Platyaxum colonies and the reconstruction of the Laskowa MCE, and we are deeply indebted to him for this work. Dr. A. Boczarowski (Sosnowiec) kindly made his specimens available for the study. The managers of Laskowa Quarry, Mr. H. Ciosmak and R. ?wi?tek, are cordially thanked for allowing access to the quarry. Separate thanks are due to J. Pickett (Sydney) for commenting on the final version of the text and linguistic corrections.Recent mesophotic coral ecosystems (MCE) occur at depths between 30 and 150 m and are characterized by dominance of platy corals. Such morphology is an effect of specific adaptation to efficient light harvesting. Here, we describe and analyze platy coral assemblages from two Middle Devonian localities in the Holy Cross Mountains (Poland) that during this time were located on the southern shelf of Laurussia at tropical latitudes. The Eifelian argillaceous sediments of Skały are dominated by platy and encrusting tabulate corals (Roseoporella, Platyaxum and Alveolites). Coeval faunas from the shallow-water parts of the Holy Cross Mountains basin display bulbous and branching morphology, thus indicating a Paleozoic coral zonation similar to that known in the Recent. Hence, the Skały site seems to be the oldest known MCE (ca. 390 Ma). A Givetian biostrome from Laskowa Quarry is a second example dominated by platy corals, with abundant branching forms; this site can be recognized as another Devonian MCE. Frondescent Platyaxum, common at both sites, had a growth habit similar to that of Recent Leptoseris, Mycedium or Pavona. Platy morphology is photoadaptive and may evidence photosymbiosis in tabulate (Alveolites, Roseoporella, Platyaxum) and rugose corals (Phillipsastrea). Furthermore, it may serve as a tool for recognition of the lower euphotic zone in the fossil record.National Science Center of Polan

Depositional setting of the Devonian/Carboniferous biohermal Bol’shaya Nadota Carbonate Complex, Subpolar Urals

Multi-stage development of carbonate buildups has been recognised in the Bol’shaya Nadota Carbonate Complex, in the vicinity of the town of Inta (Subpolar Urals). The growth of typical stromatoporoid-coral bioherms, characteristic of the Middle-Late Devonian stage, was terminated by the appearance of the shallow water oolitic facies, most probably at the beginning of the Famennian. During the Viséan stage the carbonate platform was reconstructed, but algalbrachiopod- coral bioherms were characterized by relatively small dimensions and an interfingering with organodetrital- oolitic facies. Sporadically, the inter-mound facies is represented by goniatite-bivalve coquinas with two new goniatite species: Goniatites olysya sp.nov. and Lusitanoceras kusinae sp.nov. The persistence of biohermal sedimentation in the Bol’shaya Nadota area is most probably caused by the specific position of the region on the boundary of two sedimentary-structural units: Lemva and Elets Zones, which corresponded to a basinal and a tectonically-active elevated part of a platform margin respectively. The overall biotic composition of the Carboniferous bioherms from Bol’shaya Nadota, situated in the northern periphery of Laurussia, falls generally within the diversity spectrum of Lower Carboniferous mounds described from the southern margin of the continent

High-Precision U-Pb Zircon Age Calibration of the Global Carboniferous Time Scale and Milankovitch Band Cyclicity in the Donets Basin, Eastern Ukraine

High-precision ID-TIMS U-Pb zircon ages for 12 interstratified tuffs and tonsteins are used to radiometrically calibrate the detailed lithostratigraphic, cyclostratigraphic, and biostratigraphic framework of the Carboniferous Donets Basin of eastern Europe. Chemical abrasion of zircons, use of the internationally calibrated EARTHTIME mixed U-Pb isotope dilution tracer, and improved mass spectrometry guided by detailed error analysis have resulted in an age resolution o

Pleistocene fauna in the Sucha Wieś (Ełk Lakeland) and Czarnucha (Augustów Plain) sections, northeastern Poland

Do badań faunistycznych wykorzystano próbki osadów pobranych z otworu wiertniczego Sucha Wieś (Pojezierze Ełckie) z głębokości 153,60-178,00 m oraz z otworu wiertniczego Czarnucha (Równina Augustowska) z głębokości 96,05-118,85 m. Z badanej serii osadów jeziorno-bagiennych opisano szczątki różnych grup zwierząt: ślimaków (Gastropoda), małży (Bivalvia), małżoraczków (Ostrazoda), ryb (Pisces), chrząszczy (Coleoptera) i innych. Do określenia wieku osadów, szczególnie przydatne okazały się mięczaki (ślimaki i małże) oraz małżoraczki. Na podstawie obecności ślimaka Lithoglyphus jahni oraz małżoraczka Scottia browniana uznano, że osady nie mogą być młodsze od interglacjału mazowieckiego.Samples collected from the Sucha Wieś borehole (Ełk Lakeland) from a depth interval of 153.60-178.00 and from the Czarnucha borehole (Augustów Plain) from a depth interval of 96.05-118.85 m were analysed for faunal content. The lacustrine-marsh deposits contain fragments of various animals including gastropods, bivalves, ostracods, fish, Coleoptera and others. Especially important for age determinations are moluscs (gastropods and bivalves) and ostracods. The presence of Lithoglyphus jahni (gastropod) and Scottia browniana (ostracod) indicates that the deposits cannot be younger than the Mazovian Interglacial

The squamation of “Ctenacanthus” costellatus (Chondrichthyes: Ctenacanthiformes) from the Carboniferous of Lublin area, south-eastern Poland

A sample of late Viséan limestone from the Włodawa IG-4 borehole, east of Lublin, Poland, yielded a piece of a tooth and a few hundred well-preserved scales comparable to those of “Ctenacanthus” costellatus Traquair, 1884 from Glencartholm, Scotland, UK. Most of the scales are typical compound body scales of the ctenacanthid type. Their crowns are composed of several separate odontodes whose distal ends are turned backwards and bases are characterised by concave undersides. In the material, there are also sparse scales with similar crowns but with flat or convex bulbous bases, as well as ornamented plates and single, star-like denticles, probably from the head region. The taxonomic status of “Ctenacanthus” costellatus was analysed and a new generic name for that species, viz. Glencartius gen. nov., is proposed

Lacustrine sediments of Eemian Interglacial at Leszczyno (Płock Upland - Central Poland)

Eemian Interglacial lacustrine sediments at Leszczyno are situated within the area of theWarta Glaciaton and slightly to the east from the maximal extent of the Vistulian Glaciaton. These sediments are situated in a wide depresion left by dead ice; its origin was controlled by tectonic and glaciotectonic conditions. Lacustrine silts and calcareus gyttja (about 2.7 m thick overlie the Warta Glacial till, and are covered by sands, silts and of the Vistulian Glaciaton (about 7.6 m thick). Palynostratigraphically, the biogenic lake sediments include 7 local pollen assemblage zones (L PAZ).Their spectra represent succession of the plant assemblages nearly of the whole protocratic stage, mesocratic stage and older segment of the telocratic stage of the Eemian Interglacial. Pollen diagram of the sediments from Leszczyno represents the north Masovian variant of the Eemian Interglacial succession, characterized by values of Abies (3%). Those of Taxus reach 5%

Regressive-transgressive cyclothem with facies record of the re-flooding window in the Late Silurian carbonate succession (Podolia, Ukraine)

The term “re-flooding window” was recently proposed as a time-interval connected with the transgressive stage of present day peri-reefal development. In the analysis presented here, a fossil record of a re-flooding window has been recognized. Nine Late Silurian carbonate sections exposed on the banks of the Dnister River in Podolia (Ukraine) have been correlated base on bed-by-bed microfacies analysis and spectral gamma ray (SGR) measurements. Correlated were sections representing settings ranging from the inner part of a shallow-water carbonate platform to its slope, through an organic buildup. The reconstructed depositional scenario has been divided into six development stages, with the first three representing a regressive interval and the latter three a transgressive interval of the basin’s history. The re-flooding window has been identified at the beginning of a transgressive part of the succession. Surprisingly, it is characterized by an extremely fast growth of a shallow, tide-dominated platform and by deposition of calciturbiditic layers in a more basinal area. The interpreted succession is a small-scale model illustrating the reaction of carbonate depositional sub-environments to sea level changes and determining the facies position of the stromatoporoid buildups within the facies pattern on a Silurian shelf. The use of SGR analyses in shallow water, partly high-energy, carbonate facies, both for correlation purposes and for identifying depositional systems, is a relatively new method, and thus can serve as a reference for other studies of similar facies assortment

Stromatoporoid beds and flat-pebble conglomerates interpreted as tsunami deposits in the Upper Silurian of Podolia, Ukraine

Tsunami deposits are currently a subject of intensive studies. Tsunamis must have occurred in the geological past in the same frequency as nowadays, yet their identified depositional record is surprisingly scarce. Here we describe a hitherto unrecognized example of probable palaeotsunamites. The Upper Silurian (Pridoli) carbonate succession of Podolia (southwestern Ukraine) contains variously developed event beds forming intercalations within peritidal deposits (shallow water limestones, nodular marls and dolomites). The event beds are represented by stromatoporoid and fine-grained bioclastic limestones, in some places accompanied by flat-pebble conglomerates. The interval with event beds can be traced along the Zbruch River in separate outcrops over a distance of more than 20 km along a transect oblique to the palaeoshoreline. The stromatoporoid beds have erosional bottom surfaces and are composed of overturned and often fragmented massive skeletons. The material has been transported landward from their offshore habitats and deposited in lagoonal settings. The flat-pebble conglomerates are composed of sub-angular micritic clasts that are lithologically identical to the sediments forming the underlying beds. Large-scale landward transport of the biogenic material has to be attributed to phenomena with very high energy levels, such as tropical hurricanes or tsunamis. This paper presents a tsunamigenic interpretation. Morphometric features of redeposited stromatoporoids point to a calm original growth environment at depths well below storm wave base. Tsunami waves are the most probable factor that could cause their redeposition from such a setting. The vastness of the area covered by parabiostromal stromatoporoid beds resembles the distribution of modern tsunami deposits in offshore settings. The stromatoporoid beds with unsorted stromatoporoids of various dimensions evenly distributed throughout the thickness of the beds and with clast-supported textures most probably represent deposition by traction. In some sections, the stromatoporoids are restricted to the lowermost parts of the beds, which pass upwards into bioclastic limestones. In this case, the finer material was deposited from suspension. The coexistence of stromatoporoid beds and flat-pebble conglomerates also allows presenting a tsunami interpretation of the latter. The propagating tsunami waves, led to erosion of partly lithified thin-layered mudstones, their fragmentation into flat clasts and redeposition as flat-pebble conglomerates