Results 131 to 140 of about 704 (154)

The late Frasnian (Upper Devonian) Kellwasser Crisis

2005
Detailed investigations of sequences containing the Kellwasser Bio-event near the Frasnian-Famennian boundary demonstrate a stepwise character of influences on different groups of organisms over a time span of more than 1 my. Therefore the term Kellwasser Crisis (KW Crisis) is introduced. Extraordinary episodes of the KW Crisis, like e.g.
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Disentangling allometry and response to Kellwasser anoxic events in the Late Devonian conodont genusAncyrodella

Lethaia, 2008
Is the ability to respond to minor perturbations a key to survival to major crisis? This idea was supported by previous studies on Late Devonian conodonts. Genera surviving the Frasnian/Famennian (F/F) crisis, at the end of the Upper Kellwasser anoxic event, had shown a response to a similar but minor event, the Lower Kellwasser (LKW). In contrast, the
Girard, Catherine, Renaud, Sabrina
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Late Devonian Kellwasser Bioevent at Echouech Borehole (EC-1) Southern Tunisia

To identify and characterise the Kellwasser event in southern Tunisia, which is the subject of this study, we revised the biostratigraphy of the Echouech cores from the late Devonian, particularly Frasnian-Famennian transition. This interval is characterised by diversified fauna.
Wissal Ghazzay-Souli, Saloua Razgallah, Daniel Vachard   +2 more
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Cyclostratigraphy and Astrochronology of the Late Devonian Kellwasser Crisis, Northern Appalachian Basin, USA

2018
Late Devonian marine mass extinctions associated with the Frasnian-Famennian stage transition (approximately 370 million years ago) occurred in a succession of extinction pulses within a narrow stratigraphic interval known as the Kellwasser Crisis. In most localities, this interval is typically only meters thick, but an expanded, 32 m thick cyclic ...
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Ichnofabrics and chemostratigraphy argue against persistent anoxia during the Upper Kellwasser Event in New York State

Palaeogeography, Palaeoclimatology, Palaeoecology, 2018
Abstract Organic-rich strata coeval with bioevents of varying magnitudes characterize global Devonian sedimentary successions. The Upper Kellwasser (UKw) black shale depositional event is coincident with the largest pulse of diversity loss within the marine Late Devonian mass extinction and has been shown to be an ecologically critical turnover for ...
Emily E. Haddad, Diana L. Boyer, Mary L. Droser, Bridget K. Lee, Timothy W. Lyons, Gordon D. Love   +5 more
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The Late Frasnian Kellwasser horizons of the Harz Mountains (Germany): Two oxygen-deficient periods resulting from different mechanisms

Chemical Geology, 2006
In the Harz Mountains (Germany), three Late Devonian sections, Aeketal, Huhnertal and Kellwassertal, were analyzed for major- and trace-element concentration. The inorganic geochemical data were used to determine the environmental conditions, associated with the deposition of the two Late Frasnian black Kellwasser horizons in a submarine-rise ...
Riquier, Laurent, Tribovillard, Nicolas, Averbuch, Olivier, Devleeschouwer, Xavier, Riboulleau, Armelle   +4 more
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Geochemical analyses of the Late Devonian “Kellwasser Event” stratigraphic horizon at Steinbruch Schmidt (F.R.G.)

1986
We report here the absence of an Ir anomaly in an exceptionally complete stratigraphic sequence across the Frasnian-Famennian boundary in the Rhenish Slate Mountains of the Federal Republic of Germany. There exists no anomaly either at the “Kellwasser Event” mass extinction horizon (Uppermost gigas-Lower triangularis Subzonal interval), or at the ...
George R. MC Ghee, Charles J. Orth, Leonard R. Quintana, James S. Gilmore, Edward J. Olsen   +4 more
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“Time-Specific Facies” and biological crises — The Kellwasser Event interval near the Frasnian/Famennian boundary (Late Devonian)

Palaeogeography, Palaeoclimatology, Palaeoecology, 2012
Abstract Features which may be called “Time-Specific Facies” (TSF) can be linked to global bioevents — or better biological crises. The Late Devonian Kellwasser (KW) Event is a classic example of such a crisis. This geologically short-lived “event” shows recurring patterns within the critical time interval, including patterns that are often minute ...
Manfred Gereke, Eberhard Schindler
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MULTI-PROXY ANALYSIS OF THE LOWER KELLWASSER EVENT IN THE APPALACHIAN BASIN

Geological Society of America Abstracts with Programs, 2021
Sarah Brisson, Andrew Bush, J. Andrew Beard, Michael T. Hren   +3 more
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Trilobites from the latest Frasnian Kellwasser Crisis in North Africa (Mrirt, central Moroccan Meseta)

2002
Feist, Raimund (2002): Trilobites from the latest Frasnian Kellwasser Crisis in North Africa (Mrirt, central Moroccan Meseta).
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