The late Frasnian (Upper Devonian) Kellwasser Crisis

2005 ◽  
pp. 151-159 ◽  
Author(s):  
E. Schindler
Keyword(s):  
Upper Devonian ◽  
Kellwasser Crisis

Revised taxonomy and autecology for the brachiopod genusAmbocoeliain the Middle and Late Devonian northern Appalachian Basin (USA)

2013 ◽  
Vol 87 (2) ◽  
pp. 277-288 ◽  
Author(s):  
James J. Zambito ◽  
Mena Schemm-Gregory
Keyword(s):  
New York ◽  
Evolutionary History ◽  
Taxonomic Revision ◽  
Appalachian Basin ◽  
Upper Devonian ◽  
Late Devonian ◽  
Environmental Preferences ◽  
History Of ◽  
Northern Appalachian Basin ◽  
Kellwasser Crisis

Brachiopods belonging toAmbocoeliaoccur ubiquitously in Middle and Upper Devonian strata of the northern Appalachian Basin. Originating during the Eifelian,Ambocoelia umbonatapersisted through numerous biocrises, but went extinct during the late Frasnian Kellwasser Crisis.Ambocoelia umbonatavar.gregaria, the only other form of this genus that is present within the New York Devonian succession, originated around the time of the Kellwasser Crisis and persisted locally into at least the latest Famennian. Examination of syntypic material ofA. umbonatavar.gregariahas resulted in the taxonomic revision of this form and elevation toAmbocoelia gregaria. Comparison of ontogenetic stages and environmental preferences ofA. umbonataandA. gregariasuggests that the latter exhibits a paedomorphic morphology that may have evolved fromA. umbonatathrough neoteny. Furthermore, these comparisons also give new autecological insights forAmbocoelia, suggesting thatA. umbonatawas capable of living in a diversity of environments by using a variety of life positions, whereasA. gregariawas likely more specialized. This taxonomic revision provides the necessary framework for revising the biostratigraphic range ofAmbocoeliaand, furthermore, the evolutionary history of this genus in relation to the Lower Kellwasser Event.

Petrophysical heterogeneity and associated lithotypes of carbonate reservoirs of Upper Devonian platform in the Republic of Bashkortostan

2018 ◽  
pp. 42-45
Author(s):  
T.V. Burikova ◽  
◽  
A.S. Dushin ◽  
O.R. Privalova ◽  
R.V. Akhmetzyanov ◽  
...  
Keyword(s):  
Upper Devonian ◽  
Carbonate Reservoirs ◽  
Republic Of Bashkortostan ◽  
The Republic

Biostratigraphic guide to Upper Devonian and Mississippian rocks along the Wasatch Front and Cordilleran Hingeline, Utah

1978 ◽  
Author(s):  
Charles A. Sandberg ◽  
Raymond Gutschick
Keyword(s):  
Upper Devonian ◽  
Wasatch Front ◽  
Mississippian Rocks

The major pre-Mississippian unconformity in Rock Canyon, central Wasatch Range, Utah

2014 ◽  
Vol 1 ◽  
pp. 1-5
Author(s):  
David Clark ◽  
Drew Derenthal ◽  
Bart Kowallis ◽  
Scott Ritter
Keyword(s):  
Upper Devonian ◽  
Large Size ◽  
Preliminary Work ◽  
Mississippian Rocks

In central Utah, the major pre-Mississippian unconformity is fairly well understood at most of the localities where it is recognized. However, the unconformity is more enigmatic in Rock Canyon of the central Wasatch Range. At this locality, dolomitization of most pre-Mississippian rocks obscures stratigraphic identification of Devonian and older units. The absence of any identifiable angular relationship further complicates resolution. Because of this, both identification of the stratigraphic level of the unconformity and, consequently, its magnitude remain controversial. Large-size dolomite samples taken in Rock Canyon at closely spaced intervals for the 3.6-m directly below definite Upper Devonian rocks yield microfossils, including conodonts, in the uppermost 1.6-m of that interval that indicate no unconformity exists between the Cambrian Maxfield Limestone and the Upper Devonian-Lower Mississippian Fitchville Dolomite at the horizon previously identified as unconformable. Rather, an unknown thickness of dolomitized Upper Devonian Pinyon Peak Formation and probable older rock (possibly Bluebell Dolomite and Victoria Formation) occurs between the top of definite Maxfield and base of the Fitchville. The identification of the unconformity horizon remains unknown. Our preliminary work outlines a promising procedure for future understanding of the magnitude and stratigraphic level of the unconformity.

Sign in / Sign up

Export Citation Format

Share Document