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1

Elemental and organic carbon proxies for redox conditions of the Oligocene formations in the Ropa Tectonic Window (Outer Carpathians, Poland) : palaeoenvironmental implications

Wójcik-Tabol P.

Annales Societatis Geologorum Poloniae

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2017

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Vol. 87, No. 1

41--53

EN

The Oligocene Grybów Succession is recognized as a counterpart of the anoxic Menilite Formation. Its comprehensive geochemical investigations are made in the key sections of the Ropa Tectonic Window (the Grybów Unit, Polish Outer Carpathians). The maceral assemblages, dominated by land-plant liptinite, vitrinite and intertinite, correspond to kerogen types II and III. A Tmax vs. HI diagram shows terrestrial kerogen type II with various additions of type III and algal kerogen type I. A variation in δ13Corg. (from –25.21 to –27.38‰) may have resulted from variations in the composition of organic matter (the content of terrestrial vs. marine organic matter), controlled by depositional setting (turbidite vs. hemipelagic). The highest TOC contents are associated with an enhanced influx of land-derived organic matter. The redox-sensitive trace elements positively correlate with TOC and TS contents. Redox conditions varied between oxic and anoxic, as was concluded from TOC-TS, V/(V+Ni) and U/Th. The turbidity currents might have ventilated the bottom waters, especially more efficiently in the proximal zone of turbidite sedimentation. Moreover, oxygenated bottom waters may have also affected the concentration of trace metals, owing to migration of the redox interface downward within the sediments.

2

First record of rare fish snake blenny Lumpenus lampretaeformis (Walbaum 1792) in the Puck Bay

Pieckiel P., Wawrzyniak W.

Biuletyn Instytutu Morskiego w Gdańsku

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2016

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Vol. 31, No. 1

7--10

EN

Snake blenny was noted for the first time in the Puck Bay [see Fig.1] on depth 42.1 m. This part of the Bay is connected with Gdańsk, deep with the maximum depth of 118 m. Snake blenny is probably a post glacial relict fish species in the Baltic. It prefers comparatively deep waters between 30 m to 120 m, as those water depths probably holds the suitable habitat for the fish for spawning and feeding life. However, considering snake blenny’s low tolerance for oxygen deficiency, which may occur in deepest parts of the Gulf of Gdansk, this species may be endangered in this area.

PL

Taśmiak długi Lumpenus lampretaeformis (Walbaum 1792) został odnotowany po raz pierwszy w wodach Zatoki Puckiej na głębokości 42,1 m (rys 1.) w bezpośrednim sąsiedztwie Głębi Gdańskiej gdzie maksymalna głębokość dochodzi do 118 m. W Bałtyku ryba ta jest prawdopodobnie reliktem pochodzenia polodowcowego. Siedliskiem taśmiaka długiego, zarówno dla celów rozrodczych jak i żerowiskowych, w Bałtyku są wody w zakresie głębokości od 30 m do 120 m. Biorąc pod uwagę wrażliwość tego gatunku na niedobory tlenowe, które występują w Bałtyku w szczególności w najgłębszych partiach wód włączając tu Głębię Gdańską, jego siedliska mogą być zagrożone.

3

Geochemical and stable isotope patterns of calcite cementation in the Upper Cretaceous Chalk, UK: Direct evidence from calcite-filled vugs in brachiopods

Hu X., Jeans C., Dickson T.

Acta Geologica Polonica

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2012

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Vol. 62, no. 2

143-172

EN

The history of research into the cementation of the Upper Cretaceous Chalk of the UK is reviewed. Calcite-filled vugs within the shell cavities of terebratulid brachiopods from the Cenomanian Chalk of eastern england have been investigated by cathodoluminesence imaging, staining, electron microprobe and stable isotope analysis. This has provided the first detailed analysis of the geochemistry of the Chalk.s cement. two cement series, suboxic and anoxic, are recognized. Both start with a Mg-rich calcite with positive [delta^13]C values considered to have been precipitated under oxic conditions influenced by aerobic ammonification. The suboxic series is characterized by positive [delta^13]C values that became increasingly so as cementation progressed, reaching values of 3.5[per mil]. Manganese is the dominant trace element in the earlier cement, iron in the later cement. Mn-and Fe-reducing microbes influenced cement precipitation and the trace element and [delta^13]C patterns. The anoxic series is characterized by [delta^13]C values that became increasingly negative as cementation progressed, reaching values of .6.5[per mil]. Trace elements are dominated by iron and manganese. Sulphate-reducing microbes influenced cement precipitation and the trace element and [delta^13]C patterns. Both cement series are related closely to lithofacies and early lithification pre-dating the regional hardening of the Chalk. The suboxic series occurs in chalk which was continuously deposited and contained hematite pigment and limited organic matter. The anoxic series was associated with slow to nil deposition and hardground development inc halks that originally contained hematite pigment but no longer do so, and an enhanced supply of organic matter.

4

PO4 release at the sediment surface under anoxic conditions: a contribution to the eutrophication of the Baltic Sea?

Schneider B.

Oceanologia

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2011

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No. 53 (1-TI)

415-429

EN

The vertical profiles of phosphate, total CO2 and oxygen/hydrogen sulphide were determined in the deep water of the Gotland Sea during March 2003 to July 2006 with a temporal resolution of 2-3 months. This time span included the shift from anoxic to oxic conditions resulting from a water renewal event, as well as the transition back to anoxic waters during the subsequent two-year stagnation period. The data from depths below 150 m were used to identify and quantify phosphate release and removal processes. The relationship between the total CO_2 generated by mineralization (CT, min) and the PO_4 concentrations indicated that the initial decrease in the phosphate concentrations after the inflow of oxygen-rich water was mainly a dilution effect. Only about one third of the PO_4 removal was a consequence of the precipitation of insoluble iron-3-hydroxo-phosphates (Fe-P), which occurred slowly at the sediment surface under oxic conditions. From the CT, min/PO4 ratios it was also concluded that the formation of Fe-P was reversed during the later phase of the stagnation, when the redoxcline approached a depth of 150 m. A phosphate mass balance was performed for four deep water sub-layers in order to quantify the dissolution of Fe-P during the stagnation period and thus to estimate the amount of Fe-P deposited during the last inflow of oxygen-rich water. A value of about 50 mmol-P m-2 was found, which refers to the specific biogeochemical conditions during the change from anoxic to oxic conditions that preceded the stagnation period.

5

Framboidy pirytowe jako wskaźniki paleośrodowiska

Zatoń M., Rakociński M., Marynowski L.

Przegląd Geologiczny

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2008

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Vol. 56, nr 2

158-164

EN

The problemof application of pyrite framboids in reconstructions of the redox conditions is presented. The characteristics of pyrite framboids, their origin and principles of application in paleoenvironmental interpretations are given. The pyrite framboid diameter distribution as indicators of redox conditions was presented on the examples of the Middle Jurassic (Upper Bajocian-Lower Bathonian) ore-bearing clays of the Polish Jura, and Upper Devonian (Middle and Upper Famennian) dark grey and black shales from Kowala (Holy Cross Mountains). It has been shown, that during the sedimentation of the ore-bearing clays, the pyrite framboids formed in the sediment, below the oxic water column; however, some episodic oscillation around the dysoxic conditions cannot be entirely excluded. During the sedimentation of the Middle Famennian dark grey shales, the redox conditions at the sea-floor oscillated around dysoxia. In both examples, the framboids are characterized by wide range of their diameters and the presence of large, >10 "my"m, framboids. On the contrary, the Upper Famennian black shales, representing the Hangenberg event, were deposited below the euxinic conditions in the water column. It is indicated by a high frequency of small-size framboids, far below 6 "my"m in diameter, and the lack of the large ones. The overlying shales, on the other hand, show the transition to more oxic conditions. The redox conditions interpreted above are in agreement with the independent biomarker analyses and paleontological observations.

6

Czarna kreda fliszu morawskiego

Waśkowska-Oliwa A., Golonka J., Strzeboński P.

Geoturystyka

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2007

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nr 1

29-36

PL

Obszarem stratotypowym dolnokredowych warstw wierzowskich jednostki śląskiej Karpat fliszowych są Morawy w Republice Czeskiej. Profile tych warstw są efektowne i ciekawe, zapisują historię geologiczną wczesnych stadiów rozwoju słabo przewietrzanego basenu śląskiego. Pośród czarnych mułowców występują ławice i soczewy piaskowcowo-mułowcowe, soczewki septariowe, koncentracje siarczków żelaza oraz skamieniałości mezozoicznych głowonogów. Wskutek silnej erozji dennej na terenie występowania wychodni warstw wierzowskich rozwijają się głęboko wcięte doliny i wąwozy z licznymi kaskadami i szypotami w dnie.

EN

The Moravia Region in the Czech Republic is the strato-type area for the Lower Cretaceous Verovice Beds of the Carpathian Flysch Silesian Unit. The most comprehensive profiles of these beds occur there, with black mudstones as the prevailing lithological variety. The Verovice Beds successions are impressive and interesting as these contain numerous geological features, reflecting anoxic sedimentary conditions. The deeply incised valleys, ravines and gorges with numerous cascading waterfalls and rapids are the result of the strong bottom erosion in the area of their occurrence.

7

The Early Toarcian environmental event

Coe A., Cohen A., Kemp D., Pearce Ch., Caswell B., Skelton P.

Volumina Jurassica

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2006

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Vol. 4, no. 1

155-156

EN

A pronounced negative carbon-isotope excursion in marine organic matter, marine carbonate and terrestrial plant material during the Early Toarcian indicates a major and sudden perturbation to the global carbon cycle, which has been previously ascribed to the release of a large volume of methane from marine methane hydrates (Hesselbo et al. 2000, Cohen et al. 2004). Associated features of this event include evidence for a 400-800% increase in global chemical weathering rate (Cohen et al. 2004), a major increase in seawater temperatures, increased global organic carbon burial, a crisis in the primary producers and mass extinctions. We have characterized the precise structure of the carbon-isotope excursion at high resolution using analyses of bulk organic carbon from organic-rich mudrocks from Yorkshire, UK (Kemp et al. 2005). Our data record 3 separate, abrupt negative shifts of up to 3 per mil each. We interpret this stepwise excursion pattern as unambiguous evidence for 3 separate pulses of methane release from methane hydrates. Evidence from other recently published papers on this event in which the above interpretation has been questioned will be discussed. We have also obtained high-resolution calcium carbonate, sulphur and total organic carbon concentration data from the same section. These data have been analysed using spectral analysis and reveal cycles that we ascribe to astronomical precession. The stratigraphic phase relationship between the cyclostratigraphy and the 3 pulses of methane release also permits a direct causal link to be made between methane hydrate dissociation and astronomical climate forcing (Kemp et al. 2005). Our new cyclostratigraphy allows us to constrain accurately the duration of different parts of the environmental perturbation, including the onset and recovery periods. New Mo-isotope data that we have produced suggest that rapid changes in the redox state of the oceans occurred on very short (thousand year) timescales during the Early Toarcian. These changes in redox are directly linked in time to the three abrupt carbon isotope shifts. We are currently completing high-resolution palaeontological studies through this interval in order to better characterize the associated mass extinction event and to understand the life habits of the marine fauna that characterize the crisis interval.

8

The effect of hypoxia and anoxia on osmotic concentrations of Corophium volutator (Pallas) from the Gulf of Gdańsk

Dobrzycka-Krahel A., Szaniawska A.

Oceanological and Hydrobiological Studies

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2005

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Vol. 34, No.1

99--109

EN

The aim of the investigations was to determine the effect of hypoxia and anoxia on the osmoregulation of Corophium volutator. The experiments were performed at salinities of 3.0, 6.6,15.0, and 25.0 PSU in conditions of hypoxia (saturation = 30% O2) and anoxia at a constant temperature of 10°C. Control experiments in aerated water were conducted simultaneously. Hypoxia (saturation = 30% O2) had no statistically significant effect on the osmoregulation of C. volutator after either 6 h or 48 h. However, after 6 h it did lower the osmotic concentration slightly. After 6 h anoxia had no effect on osmoregulation, but no subsequent effects of this factor (after 24 and 48 h) were detectable due to high animal mortality. Anoxia also had no effect on osmoregulation after 24 h at salinities of 15.0 and 25.0 PSU or 48 h at 15.0 PSU.

9

Geochemical and ecological aspects of lower Frasnian pyrite-ammonoid level at Kostomłoty (Holy Cross Mountains, Poland)

Racki G., Piechota A., Bond D., Wignall P. B.

Geological Quarterly

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2004

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Vol. 48, No 3

267--282

EN

The lower Frasnian (transitans Zone with Ancyrodella priamosica = MN 4 Zone) rhythmic basin succession of marly limestones and shales (upper Szydłówek Beds) at Kostomłoty, western Holy CrossMts., Central Poland, contains a record of the transgressive-hypoxic Timan Event in this drowned part of southern Laurussian shelf. The unique facies consists of organic-rich marly shales and a distinctive pyritic, goniatite level, 1.6mthick. The faunal assemblage is dominated by pyritized shells of diminutivemollusks with cephalopods (including goniatites Epitornoceras and Acanthoclymenia), buchioline bivalves (Glyptohallicardia) and styliolinids. This interval is marked by moderately low Th/U ratios and pyrite framboid size distributions suggestive of dysoxic rather than permanent euxinic conditions. The scarcity of infauna and bioturbation resulted in finely laminated sedimentary fabrics, as well as the low diversity of the presumed pioneer benthos (mostly brachiopods). In the topmost part of the Szydłówek Beds, distinguished by the Styliolina coquina interbedded between limestone-biodetrital layers, the above geochemical proxies and C-isotope positive shift indicate a tendency to somewhat increased bottom oxygen deficiency and higher carbon burial rate linked with a bloom of pelagic biota during high-productivity pulse. The geochemical and community changes are a complex regional record of the initial phase of a major perturbation in the earth-ocean system during a phase of intermittently rising sea level in the early to middle Frasnian, and associated with the highest positive C-isotope ratios of the Devonian.