Stratigraphy and graptolites of the Upper Ordovician Point Leamington Formation, central Newfoundland

1991 ◽  
Vol 28 (4) ◽  
pp. 581-600 ◽  
Author(s):  
S. Henry Williams
Keyword(s):  
Debris Flow ◽  
Black Shale ◽  
Strong Relationship ◽  
Late Ordovician ◽  
Black Shales ◽  
Upper Ordovician ◽  
Several Intervals

The Point Leamington Formation, as redefined herein, comprises a thick sequence of siliciclastic turbidites containing occasional Upper Ordovician graptolites and lies with the Exploits Subzone of the Dunnage Zone in central Newfoundland. The base of the unit is marked by the first coarse- to medium-grained sandstone, at a level that varies from the Dicranograptus clingani Zone to the Pleurograptus linearis Zone. Several intervals of interbedded black shales and siltstones higher in the formation yield assemblages characteristic of the P. linearis, Dicellograptus complanatus and Dicellograptus anceps zones. Debris-flow breccias occur at several levels within the Point Leamington Formation—some contain graptolitic, black shale clasts derived from the underlying Lawrence Harbour Formation—and range in age from Nemagraptus gracilis Zone to D. clingani Zone. Both the graptolite assemblages and lithostratigraphic succession of the Point Leamington Formation are similar to those of coeval rocks in southern Scotland, confirming a strong relationship between the two areas during the Late Ordovician.

Sedimentology of Upper Ordovician – Silurian sequences on New World Island, Newfoundland: separate fault-controlled basins?

1983 ◽  
Vol 20 (3) ◽  
pp. 345-354 ◽  
Author(s):  
R. J. Arnott
Keyword(s):  
Debris Flow ◽  
Black Shale ◽  
New World ◽  
Upper Ordovician ◽  
Sedimentary Sequences ◽  
Narrow Belt ◽  
Two Stages ◽  
Fault Scarps

Remapping of northeast New World Island, Newfoundland demonstrates that two major faults separate three distinct sedimentary sequences, Paleontology and sedimentology indicate that these sequences are partly equivalent in age but were deposited in separate basins of deposition that were adjacent to each other. Active Silurian faults, the Boyds Island and Byrne Cove Faults (new names), bounded the margins of these basins and directly influenced sedimentation by uplifting Ordovician volcanics, limestone, and black shale, which are found both in situ and as blocks within Silurian sediments. Silurian sediments deposited adjacent to these faults are dominated by pebbly mudstones and chaotic bedding interpreted as debris flow deposits and slumped horizons. Away from the fault scarps sedimentation was predominantly axial; it comprises resedimented conglomerates and thick- and thin-bedded sandstone turbidites.West of New World Island, similar synsedimentary faults are confined to a narrow belt south of the Lukes Arm – Sops Head Fault. Two stages of Acadian deformation overprint all structures associated with the Silurian faulting.

Mélange development in the Boones Point Complex, north-central Newfoundland

1981 ◽  
Vol 18 (3) ◽  
pp. 433-442 ◽  
Author(s):  
K. Douglas Nelson
Keyword(s):  
Debris Flow ◽  
Late Ordovician ◽  
The South ◽  
Upper Ordovician ◽  
North Central ◽  
Clastic Rocks ◽  
The North ◽  
Volcaniclastic Rocks ◽  
Acadian Orogeny

The Boones Point Complex in north-central Newfoundland is a narrow mélange belt separating Roberts Arm terrain volcanic and volcaniclastic rocks to the north from Upper Ordovician westerly derived clastic rocks to the south and east. The mélange has a sedimentary matrix and contains a polymict assemblage of blocks. Limestone blocks have yielded Llanvirn–Llandeilo conodont faunas. Sedimentologic and structural analyses indicate that the complex is composed of subaqueous debris flow deposits, which are the proximal facies equivalent of the Late Ordovician clastics to the south. This debris flow material was tectonically deformed prior to the Medial Devonian 'Acadian' orogeny, probably as a result of earlier 'Taconic' thrusting.

Katian (Late Ordovician) conodonts on the northwestern margin of the North China Craton

2021 ◽  
pp. 1-22
Author(s):  
Zhihua Yang ◽  
Xiuchun Jing ◽  
Hongrui Zhou ◽  
Xunlian Wang ◽  
Hui Ren ◽  
...  
Keyword(s):  
North China Craton ◽  
North China ◽  
Late Ordovician ◽  
Carbonate Platforms ◽  
Upper Ordovician ◽  
The North ◽  
Low Latitudes ◽  
Northwestern Margin ◽  
Conodont Fauna ◽  
Stratigraphic Range

Abstract Upper Ordovician strata exposed from the Baiyanhuashan section is the most representative Late Ordovician unit in the northwestern margin of the North China Craton (NCC). In total, 1,215 conodont specimens were obtained from 24 samples through the Wulanhudong and Baiyanhuashan formations at the Baiyanhuashan section. Thirty-six species belonging to 17 genera, including Tasmanognathus coronatus new species, are present. Based on this material, three conodont biozones—the Belodina confluens Biozone, the Yaoxianognathus neimengguensis Biozone, and the Yaoxianognathus yaoxianensis Biozone—have been documented, suggesting that the Baiyanhuashan conodont fauna has a stratigraphic range spanning the early to middle Katian. The Baiyanhuashan conodont fauna includes species both endemic to North China and widespread in tropical zones, allowing a reassessment of the previous correlations of the Katian conodont zonal successions proposed for North China with those established for shallow-water carbonate platforms at low latitudes. UUID: http://zoobank.org/7cedbd4a-4f7a-4be6-912f-a27fd041b586

scholarly journals Effect of Hydrothermal Activity on Organic Matter Enrichment of Shale: A Case Study of the Upper Ordovician and the Lower Silurian in the Lower Yangtze, South China

Minerals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 495 ◽  
Author(s):  
Yizhou Huang ◽  
Zhenxue Jiang ◽  
Kun Zhang ◽  
Yan Song ◽  
Shu Jiang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Oxygen Isotope ◽  
Shale Gas ◽  
Organic Matter Content ◽  
Hydrothermal Activity ◽  
Late Ordovician ◽  
Sedimentary Organic Matter ◽  
Upper Ordovician ◽  
Lower Silurian ◽  
Activity Intensity

The effect of organic matter on hydrocarbon potential, storage space, and gas content of shale is well-known. Additionally, present-day content of sedimentary organic matter in shale is controlled by depositional and preservation processes. Therefore, a study of the enrichment mechanisms of sedimentary organic matter provides a scientific basis for the determination of favorable areas of shale gas. In this study the Upper Ordovician Xinkailing Fm. and the first member of the Lower Silurian Lishuwo Fm. were examined. Stratigraphic sequences were identified through conventional logs and elemental capture spectrum data. Oxygen isotope analysis was applied to recover paleotemperature of seawater in the study area. The excess silicon content was calculated and the origin of the silica was determined by the Fe-Al-Mn ternary plot. The enrichment mechanism of organic matter was analyzed by two aspects: redox conditions and paleoproductivity. As a result, the stratigraphic interval was divided into two 3rd-order sequences. Through oxygen isotope, the paleotemperature of seawater was 62.7–79.2 °C, providing evidence of the development of hydrothermal activity. Analysis of excess siliceous minerals identified two siliceous mineral origins: terrigenous and hydrothermal. It also revealed an upwards decreasing tendency in hydrothermal activity intensity. Strong hydrothermal activity during the Late Ordovician, recognized as TST1, formed a weak-oxidizing to poor-oxygen environment with high paleoproductivity, which promoted organic matter enrichment. During the Late Ordovician to the Early Silurian, identified as RST1, TST2, and RST2, weakening hydrothermal activity caused the decline of paleoproductivity and increased oxidation of bottom waters, leading to a relative decrease of organic matter content in the shale. Therefore, favorable areas of shale gas accumulation in the Upper Ordovician and Lower Silurian are determined stratigraphically as the TST1, with a high total organic carbonate content. Geographically, the hydrothermally-active area near the plate connection of the Yangtze and the Cathaysian is most favorable.

scholarly journals The specificity of paleocoenosis and a trophic structure of the Upper Ordovician Bol’shaya Kos’yu reef (Northern Urals)

2020 ◽  
Author(s):  
L. A. Shmeleva ◽  
Keyword(s):  
Trophic Structure ◽  
Active Participation ◽  
Late Ordovician ◽  
Close Connection ◽  
Upper Ordovician ◽  
Northern Urals ◽  
Leading Role ◽  
Microbial Organisms

The study of the spatial-temporal and paleoecological structures of the paleocenoses of the Bolshaya Kosyu reef showed that the sphinctozoic sponges Amblysiphonelloides reticulata Rigby & Potter, 1986 and Corymbospongia sp. starting from the late Ordovician could settle in sublittoral environments with active hydrodynamics in close connection with cyanobacteria, which played a leading role in the functioning of the trophic structure of this ecosystem. Fossilized biofilms and glycocalyx, tubular and worm-like bacteriomorphs found on the surface of sponges are evidence of active participation of microbial organisms in the life of sphinctozoal sponges.

scholarly journals Erratum to “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 9 (1) ◽  
pp. 14
Author(s):  
Michael Iannicelli
Keyword(s):  
Black Shale ◽  
Environmental Chemistry ◽  
Black Shales ◽  
Photic Zone ◽  
Marine Organic Matter ◽  
Chattanooga Shale ◽  
Shale Formation ◽  
Organic Matter Biomarkers ◽  
Reference Section ◽  
Made In

Even though the author already incorporated the citation of Sinninghe-Damste & Schouten (2006) into the text of the paper, the author regrets having failed to include their full citation within the Reference Section of my above paper which is: Sinninghe-Damste, J. S. & Schouton, S. (2006). Biological markers for anoxia in the photic zone of the water column. In, Volkman, J. K. (ed.), Marine Organic Matter: Biomarkers, Isotopes and DNA, (pp. 127 – 163). The Handbook of Environmental Chemistry, vol. 2N. Springer: Berlin and Heidelberg. https://doi.org/10.1007/698_2_005 The author also needs to paraphrase a statement made in the last three lines of the 2nd paragraph on page 40 where it reads as: “Thus, we may conclude here that paleo-upfreezing of any conodont-element(s) originally buried in the pre-lithified, light-colored shale occurred in order to account for their presence in black shale”. Instead, in lieu of that statement, it should read as “At this point in time of the study, we may tentatively conclude here while completely concluding later in the study, that conodont-elements originally existing in the underlying, pre-lithified, light-colored shale, had to paleo-upfreeze vertically upward into pre-lithified, black shale sediment in order to account for their presence in lithified black shale”.

scholarly journals THE CLIMATIC SIGNIFICANCE OF LATE ORDOVICIAN–EARLY SILURIAN BLACK SHALES

2019 ◽  
Author(s):  
Alexandre Pohl ◽  
◽  
Yannick Donnadieu ◽  
Yannick Donnadieu ◽  
Guillaume Le Hir ◽  
...  
Keyword(s):  
Late Ordovician ◽  
Black Shales

scholarly journals Upper Ordovician graptolites from the Cape Phillips Formation, Canadian Arctic Islands

1987 ◽  
Vol 35 ◽  
pp. 191-202
Author(s):  
M. J. Melchin
Keyword(s):  
Great Britain ◽  
Shallow Water ◽  
Depositional Environment ◽  
Canadian Arctic ◽  
Late Ordovician ◽  
Outer Shelf ◽  
Upper Ordovician ◽  
The World ◽  
Cape Phillips Formation ◽  
Varying Length

Ashgill age graptolites have been collected from seven sections of the Cape Phillips Formation across most of its outcrop belt. The earliest graptolite zone recognisable is that of Orthograptus fastigatus. It is correla­ted with the Dicellograptus ornatus · Zone of the northern Canadian Cordilllera and the Dicellograptus complexus Subzone of the Dicel/ograptus anceps Zone of Great Britain although no dicellograptids have been found at any of the present sections. The overlying zone is that of Paraorthograptus pacificus, an ea­sily recognisable zone around much of the world. Graptolites of the C/imacograptus extraordinarius and Glyptograptus persculptus zones appear to be en­tirely absent from this formation. This is attributed to the Late Ordovician glaciation which has induced regression and submarine erosion in many areas worldwide. The earliest recognisable Silurian zone varies from section to section due to buried or barren intervals and/or hiatuses of varying length. The Parakidograptus acuminatus Zone has been recognised at only one section. At the others, the Atavograptus atavus, the Lagarograptus acinaces-Coronograptus gregarius, the Monograptus convolutus or the Monograptus spiralis Zone (s.1.) are the earliest recognisable Silurian fau­nas. Relatively low fauna! diversities in the Ashgill and lowest Llandovery portion of the section and the to­tal lack of dicellograptids are interpreted to be due to relatively shallow water, outer shelf or carbonate ramp depositional environment.

The brachiopods Alwynella and Grorudia: homeomorphic plectambonitoids in the Middle and Upper Ordovician of Baltoscandia

2007 ◽  
Vol 98 (3-4) ◽  
pp. 271-280 ◽  
Author(s):  
Linda Hints ◽  
David A. T. Harper
Keyword(s):  
New Species ◽  
Baltic Sea ◽  
Late Ordovician ◽  
Drill Core ◽  
Upper Ordovician ◽  
The Baltic Sea ◽  
New Material ◽  
The Baltic ◽  
A New Species ◽  
Water Facies

ABSTRACTTwo Ordovician plectambonitoid genera, Alwynella and Grorudia, occur in drill core sections of Latvia in the East Baltic, and in exposures and loose blocks on the Swedish Island of Öland in the Baltic Sea. The new material confirms differences between the two taxa that are assigned herein to separate families, Alwynellidae fam. nov. and Grorudiidae Cocks & Rong, 1989. In particular, the undercut cardinalia separates Alwynella from Grorudia and indicates its proximity to the sowerbyellids. The genus Grorudia, which is externally similar to Alwynella, is more closely related to the palaeostrophomenines. A new species Grorudia morrisoni sp. nov. is established in the East Baltic. The specimens from Öland are included tentatively within the genus Grorudia due to lack of interiors. Both Alwynella and Grorudia were confined to deeper-water facies in the Baltic palaeobasin, within successions ranging in age from latest Mid (late Llanvirn) to earliest Late Ordovician (mid Caradoc).

Foxe Platform and Basin Tectono-Sedimentary Element

2021 ◽  
pp. M57-2016-27
Author(s):  
Denis Lavoie ◽  
Nicolas Pinet ◽  
Shunxin Zhang
Keyword(s):  
Black Shales ◽  
Coarse Grained ◽  
Hudson Bay ◽  
Precambrian Basement ◽  
Upper Ordovician ◽  
Lower Paleozoic ◽  
Lower Silurian ◽  
The North ◽  
Marine Carbonate ◽  
Single Well

AbstractThe Foxe Platform and Basin Tectono-Sedimentary Element is an ovoid-shaped, predominantly marine basin located in the Canadian Arctic. The Paleozoic sedimentary succession (Cambrian to Silurian) unconformably overlies the Precambrian basement and reaches a maximum measured thickness of slightly over 500 metres in the only exploration well drilled in this basin. The Lower Paleozoic Foxe Platform and Basin Tectono-Sedimentary Element is surrounded by Precambrian basement and by the Paleozoic Arctic Platform to the north and by the Paleozoic-Mesozoic (?) Hudson Bay Strait Platform and Basin to the south. The Paleozoic succession consists of a Cambrian clastic-dominated interval overlain by Ordovician to lower Silurian predominantly shallow marine carbonate. Other than a single well drilled in the northern part of the basin, no subsurface information is available. Thermally immature Upper Ordovician organic matter rich calcareous black shales have been mapped on the onshore extension of the basin to the southeast. Potential hydrocarbon reservoirs consist of Cambrian porous coarse-grained clastics as well as Upper Ordovician dolostones and reefs.

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