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1

Did plate tectonics control the generic diversity of Jurassic brachiopods? One point of view

Ruban D. A.

Geologos

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2018

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Vol. 24, No. 1

79--84

EN

Possible plate tectonic controls on faunal diversity dynamics have been discussed in the geological literature for around 50 years. The new model of plate tectonic processes is here linked to Jurassic generic diversity (simple α-diversity) of brachiopods. This comparison offers three observations, four hypotheses and three unresolved issues. Most importantly, changes in the global plate root mean square speed coincided with brachiopod diversity dynamics, which can be explained hypothetically by either environmental disturbance triggered by more active plate motion or activity of any process (such as eustasy) tied to plate tectonic mechanisms and with an impact on marine benthic communities. It is also established that global generic diversity dynamics of brachiopods during the Jurassic coincided with the regional picture as established for the Northern Caucasus and the Swiss Jura Alps; this coincidence is difficult to explain with regard to plate tectonics. These and other speculative considerations do not clarify the role of the plate tectonic factor in Jurassic generic diversity dynamics of brachiopods, and, thus, they indicate important issues for further research.

2

The Late Devonian (Frasnian/Famenian) mass extinction : a proposed test of the glaciation hypothesis

Mc-Ghee G. R.

Geological Quarterly

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2014

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Vol. 58, No. 2

263--268

EN

It is argued in this paper that late Frasnian global cooling was the first step in the onset of the Late Palaeozoic Ice Age, and that the late Frasnian extinctions are analogous to the early Oligocene (Oi-1) extinctions that took place in the first step in the onset of the Cenozoic Ice Age. It is argued that the physical evidence for the existence of late Frasnian glaciation, like the Oi-1 glaciation, is largely geochemical: the sharp increases in δ18O values and positive δ13C anomalies that occurred in the late Frasnian and earliest Famennian. In addition to the geochemical evidence, also like the Oi-1 glaciation, stratigraphic calculations indicate a major sea-level fall occurred during the late Frasnian and early Famennian, a sea-level fall that is argued to have been glacially produced. It is here proposed that the best possible independent physical evidence for the existence of late Frasnian glaciation, other than the geochemical and sea-level evidence, would be the discovery of ice-rafted debris in marine sediments of late Frasnian age similar to the ice-rafted debris found in Oi-1 marine sediments (Zachos et al., 1992; Ehrmann and Mackensen, 1992).

3

Mesozoic mass extinctions and angiosperm radiation: does the molecular clock tell something new?

Ruban Dmitry A.

Geologos

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2012

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Vol. 18, No. 1

37--42

EN

Angiosperms evolved rapidly in the late Mesozoic. Data from the genetic-based approach called ’molecular clock’ permit an evaluation of the radiation of flowering plants through geological time and of the possible influences of Mesozoic mass extinctions. A total of 261 divergence ages of angiosperm families are considered. The radiation of flowering plants peaked in the Albian, early Campanian, and Maastrichtian. From the three late Mesozoic mass extinctions (Jurassic/Cretaceous, Cenomanian/Turonian, and Cretaceous/Palaeogene), only the Cretaceous/Palaeogene event coincided with a significant, abrupt, and long-term decline in angiosperm radiation. If their link will be further proven, this means that global-scale environmental perturbation precluded from many innovations in the development of plants. This decline was, however, not unprecedented in the history of the angiosperms. The implication of data from the molecular clock for evolutionary reconstructions is limited, primarily because this approach deals with only extant lineages.

4

Proliferation of abnormal palynoflora during the end-Devonian biotic crisis

Filipiak P., Racki G.

Geological Quarterly

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2010

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Vol. 54, No 1

1-14

EN

The dispersed miospore assemblage of the Retispora lepidophyta-Verrucosisporites nitidus (LN) Zone from the Holy Cross Mountains(Poland) is marked by enrichment (above 4%) in abnormal spore morphotypes during a terrestrial flora turnover close to the Devonian-Carboniferous boundary, recorded just above the Hangenberg Black Shale level. Incomplete and complete tetrads represent mostly Vallatisporites spp., supplemented by Grandispora, Retusotriletes and Apiculiretusispora. Additional peculiar morphotypes, marked byanomalous overall shape and ornamentation, are interpreted as mutated varieties of Vallatisporites based on intermediate morphologicalstages, connecting them with this well known genus. This relatively high aberrant palynomorph frequency is accompanied by volcanicash intercalations, as well as by charcoal debris and polycyclic aromatic biomarkers indicative of forest wildfire. Thus, the anomalousspore morphology could reflect the mutagenic effect of regional acidification due to explosive volcanism. However, palynological literature data from NW France and Canada highlight the possibility of a supra-regional mutated miospore signal near the Devonian-Carboniferous boundary, and there is need for high-resolution studies of the LN Zone to examine this. The end-Permian scenario of abnormalfloral growth in immensely stressed habitats may therefore apply to other potentially volcanically-induced biotic turnovers.

5

High resolution biostratigraphy based on planktic foraminifera across the Cretaceous-Paleogene transition at the Bidart section (SW France)

Gallala N., Zaghbib-Turki D.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

243-255

EN

Based on high resolution biostratigraphic analysis of planktic foraminifers, it is confirmed that the Bidart section (eastern margin of the Atlantic Ocean) represents a continuous Cretaceous-Paleogene (K-Pg) succession. Nevertheless, the foraminiferal species Plummerita hantkeninoides, regarded as a latest Maastrichtian marker species, is absent and Abathomphalus mayaroensis ranges to the top of the Maastrichtian (= K/Pg boundary). Pseudoguembelina hariaensis is present throughout the succession, and it is proposed herein to substitute Pl. hantkeninoides as the marker of the uppermost Maastrichtian. At least 53 out of 72 species became suddenly extinct at the K/Pg boundary, defined by the Ir anomaly (Bonte et al. 1984; Delacotte et al. 1982). The extinct species are represented by globotruncanids and large heterohelicids, characteristic of the tropical-subtropical deep photic sea water under the mesotrophic conditions of the Late Maastrichtian. The Lower Danian succession (the zones of Guembelitria cretacea, Parvularugoglobigerina eugubina, Parasubbotina pseudobulloides) is less expanded than at El Kef (Tunisia) [the Global Stratotype Section and Point (GSSP) for the Cretaceous/Paleogene (K/Pg) boundary] or at Elles (Tunisia) [its auxiliary section].

6

Zagadka późnokredowego wymierania

Nowak B.

Przegląd Geofizyczny

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2008

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Z. 2

167-179

PL

Artykuł skupia się na problemie jednego z największych kryzysów świata organicznego w dziejach Ziemi, mającego miejsce na granicy kredy i paleogenu, w wyniku którego wyginęło wiele grup zwierząt, m.in. znane wszystkim dinozaury. W artykule ukazano poglądy różnych badaczy, wyjaśniające późnokredowe wymieranie, skupiając się w znacznej mierze na dominującej obecnie teorii impaktowej, sprecyzowanej przez Waltera i Luisa Alvarezów. Artykuł ten jest pewnego rodzaju śledztwem, w którym podjęto próbę rekonstrukcji wydarzeń z końca kredy oraz wskazano ofiary, które nie przetrwały zmian środowiska, zachodzących pod koniec mezozoiku. Ponadto ukazano dowody geologiczne i paleontologiczne, potwierdzające teorię Alvarezów, nie omijając danych, które przemawiają za pozostałymi hipotezami.

EN

The article discusses one of the direst crises in the history of the organic life on Earth. The event that took place at the Cretaceous/Paleogene transition (65 MY ago) was the cause of mass extinction of many animal species including well known dinosaurs. The article reviews hypotheses of various scientists explaining late Cretaceous demise focusing on the prevailing impact theory by Luis and Walter Alvarez. This essay is sort of investigation where the author attempts to reconstruct the events of the Upper Cretaceous Period. It also presents the victims that were unable to adapt to environmental changes of the late Mesozoic Era. Moreover, the article presents geological and paleontological arguments for Alvarez' theory without omitting the evidence that supports alternative theories.

7

Phanerozoic paleoenvironment and paleolithofacies maps : Mesozoic

Golonka J.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2007

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T. 33, z. 2

211-264

EN

The paper presents the detailed plate tectonic, paleogeographic, paleoenvironment and paleolithofacies maps for eight Mesozoic time intervals. The most significant Triassic convergent event was the Indosinian orogeny, the collision of Indochina and Indonesia with South China, and consolidation of Chinese blocks. The continued northward drift of the Cimmerian continents corresponded with the closing of the Paleotethys and opening of the Neotethys Ocean. Plate tectonic activity around the Triassic-Jurassic boundary caused paleogeographic and paleoclimatic change, which triggered mass extinction. The rifting in the Atlantic during the Early Jurassic was followed by Middle and Late Jurassic spreading. Cretaceous was the time of the farther spreading of Central Atlantic, as well as origin of South Atlantic and Indian oceans. These events were leading to the maximum dispersion of continents during Phanerozoic times.

PL

Artykuł przedstawia szczegółowe mapy obrazujące tektonikę płyt, paleogeografię, paleośrodowisko i paleolitofacje ośmiu mezozoicznych przedziałów czasowych. Mapy te dotyczą przedziałów czasowych w obrębie triasu, jury i kredy. Głównym konwergentnym wydarzeniem w okresie późnego triasu była orogeneza indochińska, czyli kolizja Indochin i Indonezji z południowymi Chinami, oraz konsolidacja bloków chińskich. Postępujący w kierunku północnym dryft płyt kimeryjskich spowodował zamykanie oceanu Paleotetyda i otwieranie się oceanu Neotetyda. Aktywna tektonika płyt na granicy triasu i jury spowodowała zmiany paleogeograficzne i paleoklimatyczne, które wywołały masowe wymieranie gatunków fauny i flory. Rifting Atlantyku centralnego w okresie wczesnej jury poprzedził środkowojurajski i późnojurajski spreding tego oceanu. W kredzie nastąpił dalszy spreding Atlantyku centralnego, jak również narodziny Atlantyku południowego i Oceanu Indyjskiego. Wydarzenia te prowadziły do największego w fanerozoiku rozproszenia kontynentów.

8

Phanerozoic paleoenvironment and paleolithofacies maps : late Palezoic

Golonka J.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2007

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T. 33, z. 2

145-209

EN

The paper presents the detailed plate tectonic, paleogeographic, paleoenvironment and paleolithofacies maps for eight Late Paleozoic time intervals. These maps are dealing with the Devonian, Carboniferous and Permian time slices. The relationship of the continental configuration, lithofacies, tectonics and climate from the disassembly of Oldredia to the assembly of Pangea is clearly depicted on this series of reconstructions. The distribution of lithofacies shows climatic change associated with continental disassembly and assembly. The breakup of continents and origin of oceans generated basins related to rifting and passive margin development. The assembly of continents contributed to the formation of foreland basins. The subduction zones are related to the back--arc basins. The biological extinction events were perhaps related to the plate reorganization and mantle plume activity.

PL

Artykuł przedstawia szczegółowe mapy obrazujące tektonikę płyt, paleogeografię, paleośrodowisko i paleolitofacje ośmiu przedziałów czasowych późnego paleozoiku. Mapy dotyczą szeregu przedziałów czasowych w obrębie dewonu, karbonu i permu. Wzajemne stosunki pomiędzy konfiguracją kontynentów, litofacjami, tektoniką płyt i klimatem, jakie panowały w okresie od rozpadu superkontynentu Oldredia aż po powstania nowego superkontynentu Pangen, są wyraźnie zaznaczone na poszczególnych mapach tworzących spójną serię rekonstrukcji palinspastycznych. Rozkład litofacji jest wyraźnie związany z rozpadem i łączeniem się kontynentów, a także ze zmianami klimatu wywołanymi tektoniką płyt. Rozpad kontynentów i tworzenie się oceanów wpłynęło na powstanie basenów związanych z ryftingiem i rozwojem krawędzi pasywnych. Łączenie się kontynentów przyczyniło się do tworzenia basenów przedgórskich. Strefy subdukcji związane są z basenami załukowymi. Zmiany klimatu i wymieranie są związane z reorganizacją płyt i aktywnością pióropuszy płaszcza.

9

Otwornice bentosowe a granica kreda/paleogen (K/P) w profilu Ain Settara, Tunezja

Peryt D., Alegret L., Molina E.

Przegląd Geologiczny

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2003

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Vol. 51, nr 12

1069-1074

PL

Z odsłonięcia Ain Settara (północna Tunezja) zbadano ponad 12-metrowy profil osadów najwyższego mastrychtu (2,5 m) i dolnego paleogenu (9.6 m) reprezentujący następujące poziomy otwornicowe: Plummerita hantkeninoides, Guembelitria cretacea, Parvularugoglobigerina eugubina i Parasubbotina pseudobulloides . W osadach najwyższego mastrychtu zespoły otwornic bentosowych są zróżnicowane pod względem taksonomicznym z podobnym udziałem form infaunalnych i epifaunalnych. Dramatyczna zmiana w strukturze zespołów otwornic bentosowych jest równoczesna z tworzeniem się warstewki z anomaliami geochemicznymi, tj. w spągu poziomu Guembelitria cretacea, gdzie zróżnicowane i o niskiej dominacji zespoły otwornicowe zostają zastąpione przez zespoły zubożone pod względem taksonomicznym a zdominowane przez epifaunalne morfogrupy. W tym momencie 14 rodzajów zanika. Niektóre z nich wymierają, podczas gdy inne pojawiają się ponownie w dolnym danie jako taksony Łazarza. Naszym zdaniem gwałtowny spadek dopływu pokarmu będący skutkiem załamania produkcji pierwotnej i równoczesnej zmiany w składzie fitoplanktonu (z przewagi nanoplanktonu wapiennego na przewagę bruzdnic) mogły być bezpośrednią przyczyną restrukturyzacji zespołów otwornic bentosowych. Globalne załamanie produkcji pierwotnej było prawdopodobnie skutkiem impaktu asteroidu na półwyspie Jukatan.

EN

The outer shelf-upper bathyal section across the Cretaceous/Paleogene (K/P) boundary at Am Settara (Central Tunisia) has been studied for quantitative changes in benthic foraminiferal assemblages. The studied interval extends from 2.5 m below to 9.6 m above the Cretaceous/Paleogene (K/P) boundary and encompasses the uppermost Plummerita hantkeninoides, Guembelitria cretacea, Parvularugoglobigerina eugubina and Parasubbotina pseudobulloides planktonie foraminiferal zones. In the uppermost Maastrichtian benthic foraminiferal assemblages are highly diversified and composed of mixed epifaunal and infaunal morphogroups. The dramatic change in the structure of benthic foraminiferal assemblages corresponds to the layer with the impact evidence, i.e., at the base of the Guembelitria cretacea Zone where highly diversified, low-dominance Upper Maastrichtian assemblages with infaunal and epifaunal morphogroups were suddenly replaced by taxonomically impoverished assemblages, strongly dominated by epifaunal morphogroups. At this level several species with inferred infaunal mode of life disappeared. Some of them went extinct, whereas others reappeared in the Lower Danian as Lazarus taxa. We interpret that a sudden breakdown of the food supply as a consequence of a collapse in primary productivity and simultaneous changes in the phytoplankton composition (from calcareous nannoplankton to dinoflagellates) resulted in extinction or temporary emigration of most infaunal morphogroups. The sudden collapse of primary productivity probably resulted from the impact of the K/P asteroid.

10

The Carbon biogeochemical cycle across the Permian-Triassic boundary strata and its implications : isotope record from the Changhsingian Stage at Meishan, south China

Gruszczyński M.

Acta Geologica Polonica

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2003

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Vol. 53, nr 3

167-179

EN

The new dataset of the carbon and oxygen stable isotope values across the sedimentary sequence of the Changhsingian Stage at Meishan, south China documents the carbon biogeochemical cycle in detail. The cycle began with storage of organic carbon (C[org]), mainly as biogenic carbon dioxide in clathrates, and carbon dioxide from anaerobic methane oxidation (AMO) in the stratified sea water masses, which is reflected by a rapid increase in the [delta izotop C13] values. Storage of C[org] demanded a large biomass productivity, and thus consumption of a vast amount of carbon dioxide, which would have been associated with climatic oceanic water cooling. Oceanic water cooling and enhanced volcanism is actually reflected by a gradual increase in the {delta izotop O18] values. The longterm stasis between C[org] burial and reburial was then achieved, as rflected by the stable course of the [delta izotop C13] curve. At the same time, cool water circulation caused a continuous increase in the [delta izotop O18] values. At the end of the cycle, several factors including earthquakes and other tectonic movements marking the onset of major Siberian volcanism, together with a local temperature increase resulted in a change of ocean circulation, caused mixing of stratified sea water masses. This was followed by destruction of the existing clathrates, degassing of carbon dioxide, oxidation of organic matter, and a rapid decrease in the oceanic [delta izotop C13] values. Apart from the carbon dioxide that was released to the atmosphere, part of the methane must have been oxidised, creating additional carbon dioxide as well as vater vapour. The carbon dioxide and water vapour must have initiated a greenhouse effect and caused thermal stratification of seawater which, in turn, initiated reconstruction of the redox in the Early Triassic. The end of the cycle was associated with the end-Permian mass extinction. The global warming associated with methane release from clathrates led to collapse of terrestrial plants. At the same time, the mixing event brought methane and organic matter for oxidation, which caused massive consumption of oxygen and extinction of the terrestrial fauna. In the marine environment, the mixing event brought water masses rich in carbon dioxide, as well as excess hydrogen ions from anoxic zones, onto shelf areas, causing a collapse of marine biota. The carbon biogeochemical cycle of the Changhsingian indicated by the initial rapid rise, long-term stasis, and final rapid drop in [delta izotop C13] values, seems to be a rule for a pattern of Phanerozoic [delta izotop C13] values in sedimentary carbonates. This suggest that a process of methane storage and release may have had a bearing on major geochemical perturbations throughout Earth history. However, methane storage, with or without the association of carbon dioxide and other forms of C[org] and its subsequent release, could have occurred in many different scenarios throughout the Phanerozoic. Therefore, the end of the carbon cycles may be associated with mass extinction only when release of methane is coupled with other phenomena, which is the case with the end-Permian event.