Ordovician Formations and Faunas, Southern Mackenzie Mountains

1975 ◽  
Vol 12 (4) ◽  
pp. 663-697 ◽  
Author(s):  
Rolf Ludvigsen
Keyword(s):  
Deep Water ◽  
Carbonate Facies ◽  
Northern Canada ◽  
Northeastern Part ◽  
Early Ordovician ◽  
The Road ◽  
Carbonate Sedimentation ◽  
Skull Formation ◽  
Tectonic Features ◽  
First Time

Ordovician strata of the South Nahanni River area occur as a western fine clastic facies with graptolitic faunas (Road River Formation) and an eastern carbonate facies with shelly faunas (Broken Skull, Sunblood, Esbataottine, and Whittaker Formations). The lithofacies are controlled by major tectonic features. In the early Ordovician the Selwyn Basin received fine clastic sedimentation (Road River) while carbonate sedimentation (Broken Skull, Sunblood, Esbataottine) was confined to the Root Basin and the fringes of the emergent Redstone Arch. Later in the Ordovician a pronounced transgression caused a marked eastwardly shift of facies belts and resulted in the flooding of the Arch and deposition of a widespread carbonate sheet (Whittaker) in the northeastern part of the study area.The carbonate facies of the Root Basin and south of the Redstone Arch contains a complete record of shelly faunas of Canadian to, probably, Maysvillian age. The Broken Skull Formation consists of craggy weathering, variably sandy carbonates and contains, in its highest parts, the Hesperonomia fauna (Canadian). The Sunblood Formation consists of generally resistant, red-orange-buff weathering limestones and minor dolostones and contains two faunas; the Orthidiella-'Goniotelina' fauna (Whiterockian) and the Bathyurus sp. 1 fauna (?Chazyan). The Esbataottine Formation (proposed) comprises moderately recessive, grey-buff weathering limestones and contains two faunas; the Mimella fauna (Chazyan) and the Doleroides fauna (Blackriveran). The lower Whittaker Formation (Trentonian to ?Maysvillian) comprises three lithosomes containing discrete faunas which appear to represent coeval communities: The Strophomena-Ceraurus fauna in thinly bedded, argillaceous limestones; the Bighornia-Thaerodonta fauna in well bedded, nonargillaceous limestones; and the Hesperorthis-Oepikina fauna in well bedded dolostones. A unique fauna of deep water aspect, the Cryptolithus-Anataphrus fauna, occurs in shales and black limestones of the Road River Formation and is, in part, equivalent to the faunas of the lower Whittaker Formation. The Sunblood, Esbataottine, and Whittaker Formations contain abundant and well preserved silicified trilobites; many of which are reported for the first time from western and northern Canada.

The sequence and correlation of Early Ordovician (Arenig) graptolite faunas in the Richardson Trough and Misty Creek Embayment, Yukon Territory and District of Mackenzie, Canada

2006 ◽  
Vol 43 (12) ◽  
pp. 1791-1820 ◽  
Author(s):  
D E Jackson ◽  
A C Lenz
Keyword(s):  
Northwest Territories ◽  
Deep Water ◽  
Yukon Territory ◽  
Early Ordovician ◽  
The Road ◽  
Bedded Chert ◽  
First Occurrence ◽  
Mackenzie Mountains ◽  
First Time

Four graptolite biozones are recorded from the Arenig portion of the Road River Group in the Richardson and Mackenzie mountains in the Yukon and Northwest Territories. In ascending order, these zones are Tetragraptus approximatus, Pendeograptus fruticosus, Didymograptus bifidus, and Parisograptus caduceus australis (new). The Castlemainian stage may be represented by nongraptolitic massive bedded chert. The Arenig–Llanvirn boundary is drawn below the first occurrence of Undulograptus austrodentatus. Fifty-four graptolite taxa are present, and 16 of these species and subspecies are recorded for the first time in this deep-water biotope, namely, Didymograptus? cf. adamantinus, D. asperus, D. dilatans, D. cf. kurcki, D. validus communis, Holmograptus aff. leptograptoides, H. sp. A, Isograptus? sp. nov. A, I. ? dilemma, Keblograptus geminus, Pseudisograptus manubriatus harrisi, Ps. m. koi, Ps. m. janus, Ps. cf. tau, Xiphograptus lofuensis, and Zygograptus cf. abnormis.

Batocrinidae (Crinoidea) from the Lower Mississippian (lower Viséan) Fort Payne Formation of Kentucky, Tennessee, and Alabama: systematics, geographic occurrences, and facies distribution

2018 ◽  
Vol 92 (4) ◽  
pp. 681-712
Author(s):  
William I. Ausich ◽  
Elizabeth C. Rhenberg ◽  
David L. Meyer
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Dominant Species ◽  
Carbonate Facies ◽  
Shallow Marine ◽  
First Time ◽  
Water Carbonate ◽  
Shallow Water Carbonate ◽  
Water Facies ◽  
Mixed Carbonate

AbstractThe Batocrinidae are characteristic faunal elements in Lower Mississippian shallow-marine settings in North America. Recent delineation of objectively defined genera allows a reexamination of batocrinid species and their distribution in the Fort Payne Formation (early Viséan, late Osagean), a well-studied array of carbonate and siliciclastic facies. The Fort Payne batocrinid fauna has 14 species assigned to six genera, plus hybrid specimens.Magnuscrinus spinosus(Miller and Gurley, 1895a) is reassigned to its original placement inEretmocrinus. Hybrid specimens (Ausich and Meyer, 1994) are regarded asEretmocrinus magnificus×Eretmocrinus spinosus.Macrocrinus casualisis the dominant species ofMacrocrinusin the Fort Payne, andM.mundulusandM.strotobasilarisare recognized in the Fort Payne Formation for the first time.Magnuscrinus cumberlandensisn. sp. is named, 13 species are designated as junior synonyms, the name for the hybrid specimens is changed toEretmocrinus magnificus×Eretmocrinus spinosus, and the previous occurrences of two species in the Fort Payne are rejected. The Eastern Interior Seaway was a mixed carbonate-siliciclastic setting with both shallow- and deep-water epicontinental sea facies ranging from relatively shallow autochthonous green shales to deep-water turbidite facies.Dizygocrinuswas restricted to shallow-water carbonate and siliciclastic facies,Eutrochocrinuswas restricted to shallow-water carbonate facies, andMagnuscrinuswas restricted to deep-water facies. Species distributions varied fromAbatocrinus steropes,Alloprosallocrinus conicus,Macrocrinus mundulus, andUperocrinus nashvillae, which occurred throughout the Eastern Interior Seaway, to species that were restricted to a single facies.Eretmocrinus magnificus,Alloprosallocrinus conicus, andUperocrinus robustuswere the dominant batocrinids in the Fort Payne Formation.UUID:http://zoobank.org/703aafd8-4c73-4edc-9870-e2356e2d28b8

Contribution to the flora of marine algae of the coastal zone of the northeastern part of the Sea of Okhotsk

2018 ◽  
Vol 52 (1) ◽  
pp. 63-73
Author(s):  
N. V. Evseeva
Keyword(s):  
Coastal Zone ◽  
Sea Of Okhotsk ◽  
Marine Algae ◽  
Herbarium Material ◽  
Northeastern Part ◽  
The Sea Of Okhotsk ◽  
The Family ◽  
First Time

The revision of the herbarium material, collected in the northern part of the Sea of Okhotsk in 1965–1966 and stored in VNIRO, allowed to expand the taxonomic list of macrophyte algae of the coastal zone of this area. The locations of discovery of 24 previously unmentioned species are described. Myrionema balticum, Ulvella repens, Syncoryne reinkei, Acrochaetium arcuatum were found in the Sea of Okhotsk for the first time. Most species new for the Sea of Okhotsk is represented by epiphytes of the family Ulvellaceae (Chlorophyta). The final taxonomic list of this region, including literature data, consists of 169 species.

ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF

2017 ◽  
Author(s):  
Svetlana Rubtsova ◽  
Svetlana Rubtsova ◽  
Natalya Lyamina ◽  
Natalya Lyamina ◽  
Aleksey Lyamin ◽  
...  
Keyword(s):  
Black Sea ◽  
Field Intensity ◽  
Deep Water ◽  
Coastal Waters ◽  
Integrated Management ◽  
Abiotic Factors ◽  
Environmental Safety ◽  
The Black Sea ◽  
Intensity Increase ◽  
First Time

The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.

Deep Water Scientific Drilling in Lake Malawi, Africa

2006 ◽  
Vol 40 (1) ◽  
pp. 29-35
Author(s):  
K. Moran ◽  
M. Paulson ◽  
M. Lengkeek ◽  
P. Jeffery ◽  
A. Frazer
Keyword(s):  
Deep Water ◽  
Lake Malawi ◽  
Design Work ◽  
Scientific Drilling ◽  
Drilling Rig ◽  
Core Recovery ◽  
Lake Floor ◽  
Drilling System ◽  
Rift Valley Lakes ◽  
First Time

A new deep water drilling system was developed and applied to recover deeply buried sediments for scientific analyses in one of the deep rift valley lakes of Africa—Malawi. This approach overcame the difficulty of maintaining position over a drill site in a remotely located, large, deep lake. Environmental conditions in Lake Malawi are similar to deep water marine settings and, as such, a marine approach was adopted for the Lake Malawi Drilling Project (LMDP). In February and March 2005, the modified pontoon, Viphya, successfully completed a scientific drilling expedition in Lake Malawi. This expedition recovered core at depths greater than 380 m below lake-floor in water depths as great as 600 m. The major refit of Viphya included installation of a moonpool, bridge, crew accommodations, mess, washroom, power system, dynamic positioning, and a drilling system. These major modifications required early pontoon surveys and naval architectural analyses and design work prior to their commencement. The expedition also used modified scientific coring tools with a marine geotechnical drilling rig for the first time, resulting in excellent core recovery and quality.

scholarly journals Depositional, diagenetic and stratigraphic aspects of Macaé Group carbonates (Albian): example from an oilfield from Campos Basin

2015 ◽  
Vol 45 (2) ◽  
pp. 243-258 ◽  
Author(s):  
Juliana Okubo ◽  
Ricardo Lykawka ◽  
Lucas Veríssimo Warren ◽  
Julia Favoreto ◽  
Dimas Dias-Brito
Keyword(s):  
Deep Water ◽  
Carbonate Rocks ◽  
Facies Analysis ◽  
Sedimentary Facies ◽  
Fair Weather ◽  
Thin Sections ◽  
Carbonate Sedimentation ◽  
Diagenetic Processes ◽  
Campos Basin ◽  
Facies Associations

<p>Carbonate rocks from the Macaé Group (Albian) represent an example of carbonate sedimentation related to the drift phase in Campos Basin. This study presents depositional features, integrating them with diagenetic and stratigraphic aspects of the Macaé Group carbonates including the upper part of the Quissamã Formation and the lower part of the Outeiro Formation. Macroscopic analyses in cores and microscopic ones in thin sections allowed the recognition of eleven sedimentary facies - nine of them corresponding to the Quissamã Formation and two of them representing the Outeiro Formation. These facies were grouped into five facies associations. Oolitic grainstones and oncolitic grainstones are interpreted to be deposited in shallow depth probably in shoals above the fair weather wave base. The interbanks between shoals were formed in less agitated waters and characterized by deposition of peloidal bioclastic packstones and wackestones representative of sedimentation in calm waters. Bioclastic packstones and oolitic packstones/wackestones represent allochthonous deposits related to the beginning of the regional drowning that occur in upper Quissamã Formation. Pithonellids wackestones and bioclastic wackestones with glauconite are related to deep water deposits, characteristics of the Outeiro Formation. Post-depositional features revealed the action of diagenetic processes as, micritization, cimentation, dissolution, compaction, dolomitization and recrystallization occurred during the eo- and mesodiagenesis phases. Vertical facies analysis suggests shallowing upward cycles stacked in a sequence progressively deeper towards the top (from the Quissamã Formation to the Outeiro Formation).</p>

scholarly journals Upper Barremian-Lower Aptian Urgonian limestone's in the Rakova bara section (Carpatho-balkanides, NE Serbia): Analysis and comparison with adjacent areas

2010 ◽  
Vol 90 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Ivana Carevic ◽  
Darivojka Ljubovic-Obradovic ◽  
Monika Bozinovic ◽  
Velimir Jovanovic
Keyword(s):  
Shallow Water ◽  
Benthic Foraminifera ◽  
Carbonate Sedimentation ◽  
Lower Aptian ◽  
First Time ◽  
Water Carbonate ◽  
Shallow Water Carbonate

The Upper Barremian-Lower Aptian succession is recorded from a limestone sequence that crops out in the surrounding of Rakova Bara in the Carpatho-Balkanides range in northeastern Serbia. The micropalaeontological and sedimentological studies lead to recognition of the two types of microfacies. The benthic foraminiferal association consists of Vercorsella laurentii, Rumanoloculina robusta, Praechrysalidina infracretaceae, Dictyoconus gr. arabicus, Debarina hahounerensis, Charentia cuvilieri and Pseudocyclammina lituus that confirm the stratigraphical and palaeoenvironmental connection of the microfossil assemblages with the classical Urgonian-type, shallow-water carbonate sedimentation. The association documented for the first time in the study area is considered typical of the Tethyan Realm. The stratigraphical position of the benthic foraminifera species within the Upper Barremian-Lower Aptian interval is discussed. The Urgonian Limestone's of the studied section are comparable with adjacent areas of eastern Serbia and Romanian South Carpathians. .

scholarly journals Zeiform mouthbrooding in the deepsea – dispelling a myth

2020 ◽  
Author(s):  
Ralf ◽  
G. David Johnson ◽  
Kevin Conway
Keyword(s):  
Deep Water ◽  
Deep Sea ◽  
Developmental Stages ◽  
Extended Period ◽  
Marine Fishes ◽  
Early Developmental Stages ◽  
Water Fish ◽  
First Time ◽  
Early Developmental ◽  
Deep Sea Fauna

Mouthbrooding or oral incubation, the retention of early developmental stages inside of the mouth for an extended period of time, has evolved multiple times in bony fishes1,2. Though uncommon, this form of parental care has been documented and well-studied in several groups of freshwater fishes but is also known to occur in a small number of marine fishes, all inhabiting coastal waters1,2. A recent paper3, reported for the first time mouthbrooding in a deep-water fish species, the zeiform Parazen pacificus, which according to the authors “fills in a gap in the larval literature for this family of fishes and prompts further investigation into other novel reproductive modes of deep-sea fauna.”

Halimeda incrassata (Bryopsidales, Chlorophyta) reaches the Canary Islands: mid- and deep-water meadows in the eastern subtropical Atlantic Ocean

2018 ◽  
Vol 61 (2) ◽  
pp. 103-110 ◽  
Author(s):  
Carlos Sangil ◽  
Laura Martín-García ◽  
Julio Afonso-Carrillo ◽  
Jacinto Barquín ◽  
Marta Sansón
Keyword(s):  
Atlantic Ocean ◽  
Canary Islands ◽  
Deep Water ◽  
Population Coverage ◽  
Isolated Populations ◽  
La Palma ◽  
Soft Bottoms ◽  
The Caribbean ◽  
Marine Flora ◽  
First Time

AbstractExtensive offshore meadows ofHalimeda incrassataare documented for the first time in sandy bottoms of La Palma, Canary Islands.Halimeda incrassataforms dense sublittoral assemblages between 20 and 55 m, but isolated populations occur down to 65 m depth. This species currently spreads over an area of 9.14 ha. Population coverage varies with depth, with the highest values at 35–40 m and an average cover of 62.34%. The calcified segments ofH. incrassataact as a stable substratum in these soft bottoms for the growth of other macroalgae, such as the rhodophytesLophocladia trichocladosandCottoniella filamentosa. Specimens reach lengths of up to 10 cm, shorter than individuals from the Caribbean. Although it is difficult to ascertain whether this species is a recent introduction, there is evidence of a correlation between the increase in population coverage and recent ocean warming, constituting another example of the tropicalization of the marine flora of this region.

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