scholarly journals Stratigraphy of the Chattanooga Shale (Upper Devonian and Lower Mississippian) in vicinity of Big Stone Gap, Wise County, Virginia, with a section on petrology

10.3133/b1499 ◽  
1981 ◽  
Keyword(s):  
Upper Devonian ◽  
Chattanooga Shale

scholarly journals A Perspective on Stratigraphic, Vertically-Upward “Displacements or Dislocations” of Conodont-Elements: An Example From the Upper Devonian, Pre-Lithified, Black Shales of the Chattanooga Shale Formation In Tennessee, USA

2019 ◽  
Vol 8 (2) ◽  
pp. 35
Author(s):  
Michael Iannicelli
Keyword(s):  
Black Shale ◽  
Black Shales ◽  
Upper Devonian ◽  
Cold Climate ◽  
Fine Grained ◽  
Sedimentary Deposits ◽  
Chattanooga Shale ◽  
Shale Formation ◽  
Freezing Temperatures ◽  
Age Determinations

Stratigraphic “displacements or dislocations” are coarse clasts and / or objects (such as unaltered remains or conodont-elements) slowly mobilizing or migrating vertically upward through a fine-grained matrix by a cryogenetic process known as “upfreezing” due to freezing temperatures. The process was originally established by periglaciologists and cold-climate geomorphologists who applied it only to unconsolidated, sedimentary deposits. In this study, the process is applied to the marine, pre-lithified, black shales of the Upper Devonian, Chattanooga Shale Formation, specifically in Tennessee, USA. The importance of this recognition is to alert paleontologists and stratigraphers about the strong possibility of inaccurate age-determinations made concerning coarse objects such as a conodont-element (denticles) (but not fossilized molds) because of their fossilized presence in age-determined, stratigraphic, rock levels when the apatite-composed denticles may have instead been initially deposited at a lower stratigraphic level during pre-lithification of the fine-grained, host-rock (shale) before the paleo-upfreezing process mobilized the denticles upwards. Many lines of evidences are given in this study towards apparent, predominant, freezing temperatures in the pre-existing, Chattanooga Sea of the Appalachian Basin, including particular, supposed, bioturbated, pre-lithified, organic black shale that is reinterpreted here as cryoturbated, pre-lithified, organic, black shale.

Protosalvinia Dawson and associated conodonts of the upper Trachytera Zone, Famennian, Upper Devonian, in the eastern United States

2009 ◽  
Vol 83 (1) ◽  
pp. 70-79 ◽  
Author(s):  
D. Jeffrey Over ◽  
Remus Lazar ◽  
Gordon C. Baird ◽  
Juergen Schieber ◽  
Frank R. Ettensohn
Keyword(s):  
United States ◽  
Appalachian Basin ◽  
Upper Devonian ◽  
Illinois Basin ◽  
Eastern United States ◽  
Southern Appalachian ◽  
Chattanooga Shale ◽  
New Albany Shale ◽  
Northern Appalachian Basin

Protosalvinia first occur in association with conodonts of the Upper trachytera Zone and below the Three Lick Bed in the Ohio Shale and the Ellicott Shale of the central and northern Appalachian Basin, as well as in the Clegg Creek Member of the New Albany Shale of the Illinois Basin. In the Chattanooga Shale of the southern Appalachian Basin, Protosalvinia are found no lower than the Upper marginifera Zone or associated with obviously reworked conodonts in the Middle expansa Zone. Regionally Protosalvinia are associated with a disconformity and may be found with conodonts of the Lower expansa Zone.

scholarly journals Supplemental Material: Biomarker evidence of algal-microbial community changes linked to redox and salinity variation, Upper Devonian Chattanooga Shale (Tennessee, USA)

2020 ◽  
Author(s):  
Yi Song ◽  
Shucheng Xie
Keyword(s):  
Microbial Community ◽  
Original Data ◽  
Upper Devonian ◽  
Salinity Variation ◽  
Chattanooga Shale ◽  
Community Changes ◽  
Aryl Isoprenoids

Table S1: original data of all proxies in this paper and concentration of each element and compound; Figure S2: Mass chromatograms of selected sample showing the distribution of (a) n-alkanes, (b) C27-C29 steranes and diasteranes (m/z 217), (c) Terpane m/z 191 fingerprint, (d) aryl isoprenoids (m/z 133 or 134).

scholarly journals Supplemental Material: Biomarker evidence of algal-microbial community changes linked to redox and salinity variation, Upper Devonian Chattanooga Shale (Tennessee, USA)

2020 ◽  
Author(s):  
Yi Song ◽  
Shucheng Xie ◽  
et al.
Keyword(s):  
Microbial Community ◽  
Original Data ◽  
Upper Devonian ◽  
Salinity Variation ◽  
Chattanooga Shale ◽  
Community Changes ◽  
Aryl Isoprenoids

Table S1: original data of all proxies in this paper and concentration of each element and compound; Figure S2: Mass chromatograms of selected sample showing the distribution of (a) n-alkanes, (b) C27-C29 steranes and diasteranes (m/z 217), (c) Terpane m/z 191 fingerprint, (d) aryl isoprenoids (m/z 133 or 134).

Biomarker evidence of algal-microbial community changes linked to redox and salinity variation, Upper Devonian Chattanooga Shale (Tennessee, USA)

2020 ◽  
Vol 133 (1-2) ◽  
pp. 409-424 ◽  
Author(s):  
Yi Song ◽  
Geoffrey J. Gilleaudeau ◽  
Thomas J. Algeo ◽  
D. Jeffrey Over ◽  
Timothy W. Lyons ◽  
...  
Keyword(s):  
Microbial Community ◽  
Organic Carbon ◽  
Upper Devonian ◽  
Photic Zone ◽  
Sharp Reduction ◽  
Green Algal ◽  
Chattanooga Shale ◽  
Lipid Biomarker ◽  
Community Changes ◽  
Microalgal Community

Abstract Late Devonian marine systems were characterized by major environmental perturbations and associated biotic community changes linked to climate change and widespread oceanic anoxia. Here, we provide high-resolution lipid biomarker chemostratigraphic records from the Upper Devonian Chattanooga Shale (Tennessee, USA) to investigate algal-microbial community changes in the southern Illinois Basin that were related to contemporaneous shifts in marine redox (as proxied by trace metals, Fe-species, and Corg/P) and salinity conditions (as proxied by B/Ga, Sr/Ba, and S/total organic carbon). The Frasnian was characterized by dominantly bacterial lipids (high hopane/sterane), near-marine salinity, and a shift from oxic to increasingly reducing conditions in response to increasing organic carbon sinking fluxes. Aryl isoprenoids and aryl isoprenoid ratios reveal that the O2-H2S chemocline was unstable and intermittently shallow (i.e., within the photic zone). The Frasnian-Famennian boundary was marked by a shift in microalgal community composition toward green algal (e.g., prasinophyte) dominance (lower C27 and higher C28 and C29 steranes), a sharp reduction in watermass salinity, and a stable O2-H2S chemocline below the photic zone, conditions that persisted until nearly the end of the Famennian. We infer that changing watermass conditions, especially a sharp reduction in salinity to possibly low-brackish conditions (<10 psu), were the primary cause of concurrent changes in the microalgal community, reflecting tolerance of low-salinity conditions by green algae. Transient spikes in moretane/hopane (M/H) ratios may record enhanced terrestrial weathering at the Frasnian-Famennian and Devonian–Carboniferous boundaries, triggered by coeval glacio-eustatic falls and increased inputs of soil organic matter. High M/H and pristane/phytane, in combination with low chemical index of alteration and K/Al, record a decrease in chemical weathering intensity during the Famennian that may have been due to contemporaneous climatic cooling, and a concurrent reduction in silt content may reflect stabilization of land surfaces by vascular plants and resulting reduced sediment yields. This study demonstrates the effectiveness of combining organic and inorganic geochemical proxies (including novel paleosalinity indices) for determination of environmental controls on the composition and productivity of plankton communities in paleomarine systems.

Conodont biostratigraphy of the Chattanooga Shale, Middle and Upper Devonian, southern Appalachian basin, eastern United States

2007 ◽  
Vol 81 (6) ◽  
pp. 1194-1217 ◽  
Author(s):  
D. Jeffrey Over
Keyword(s):  
United States ◽  
Appalachian Basin ◽  
Upper Devonian ◽  
Eastern United States ◽  
Conodont Biostratigraphy ◽  
Fine Grained ◽  
Southern Appalachian ◽  
Global Correlation ◽  
Chattanooga Shale ◽  
Conodont Fauna

The Chattanooga Shale of the southern Appalachian Basin contains a diverse conodont fauna of the high Givetian, Frasnian, and Famennian. The predominantly fine-grained strata were deposited in an offshore setting where depositional packages are separated by unconformities. Conodonts allow regional and global correlation of these strata, recognition of the Frasnian-Famennian boundary, and narrow biostratigraphic constraint of two Frasnian ash beds, MN Zone 8 for the Belpre Ash and upper MN Zone 13 for the Center Hill Ash. Three new Frasnian palmatolepid conodonts are described in open nomenclature, and the holotype ofPalmatolepis regularisCooper is reillustrated.

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