scholarly journals Dinantian conodont biostratigraphy of the Northumberland Trough

1987 ◽  
Vol 6 (2) ◽  
pp. 97-112 ◽  
Author(s):  
H. A. Armstrong ◽  
M. A. Purnell
Keyword(s):  
Shallow Water ◽  
Conodont Biostratigraphy ◽  
Shallow Subtidal

Abstract. Conodont faunas from Dinantian strata of the Northumberland Trough and Tweed Basin are described. Five zones are recognised. These zones are correlated with the standard British Stages and where possible with European and American sections. Chadian and Arundian faunas are dominated by Taphrognathus, Cloghergnathus and Cavusgnathus which typically occur in shallow intertidal and shallow subtidal environments. Holkerian and Asbian strata are barren of conodonts. In the Brigantian deeper-water genera including Gnathodus are represented. The shallow water nature of the lower faunas causes difficulty in correlation with goniatite-bearing sequences in the Craven Basin but reasonable correlations can be made to Ravenstonedale and the Avon Gorge.

Turleania rubriguttatus, a new species of pagurid hermit crab (Decapoda: Anomura: Paguroidea) from shallow water in Japan, with notes on T. senticosa (McLaughlin & Haig, 1996)

Zootaxa ◽  
2020 ◽  
Vol 4834 (1) ◽  
pp. 96-106
Author(s):  
TOMOYUKI KOMAI
Keyword(s):  
New Species ◽  
Shallow Water ◽  
Hermit Crab ◽  
Dorsal Surface ◽  
The Philippines ◽  
The Status ◽  
Shallow Subtidal ◽  
The Right ◽  
Kochi Prefecture ◽  
A New Species

A new species of the pagurid hermit crab genus Turleania McLaughlin, 1997, T. rubriguttatus, is described on the basis of two specimens, including one male and one female, from shallow subtidal waters in Kochi Prefecture, Japan. The new species appears close to T. albatrossae (McLaughlin & Haig, 1996), known from the Philippines, but the proximally unarmed dorsal surface of the right chela palm and the lack of a dorsomesial row of spines on the left cheliped carpus easily distinguish T. rubriguttatus n. sp. from T. albatrossae. Examination of the type material of T. similis Komai, 1999 and T. spinimanus Komai, 1999, and supplemental material from Japan, confirms that the two taxa are synonymous with T. senticosa (McLaughlin & Haig, 1996), as was suggested by previous authors. Re-examination clarified that in T. senticosa the maxilliped 3 has no developed arthrobranchs, and this led the author to assess the status of T. sinensis Han, Sha & An, 2016, which is also synonymised with T. senticosa. 

Windsor Group (Lower Carboniferous) conodont biostratigraphy and palaeoecology, Magdalen Islands, Quebec, Canada

1986 ◽  
Vol 23 (4) ◽  
pp. 439-453 ◽  
Author(s):  
Hilary A. Plint ◽  
Peter H. von Bitter
Keyword(s):  
Nova Scotia ◽  
Shallow Water ◽  
Lower Carboniferous ◽  
Conodont Biostratigraphy ◽  
Conodont Zonation ◽  
Total Lack ◽  
Magdalen Islands

The Taphrognathus transatlanticus, Clydagnathus windsorensis, and Gnathodus zones, initially defined in the Codroy Group of Newfoundland, were identified in the Havre-aux-Maisons Formation of the Windsor Group of the Magdalen Islands, Quebec, Canada. Recognition of these zones permits correlation within the islands and with Newfoundland and Nova Scotia. The Taphrognathus transatlanticus and Clydagnathus windsorensis zones correlate with the lower and upper macrofaunal B Subzone, respectively, whereas the Gnathodus Zone corresponds to the C, D, and E macrofaunal subzones.Tectonism and plastic movement of sulphates and chlorides have resulted in fragmentation and transport of parts of the Havre-aux-Maisons Formation. The conodont zonation complements the macrofaunal zonation permitting correlation of fragmented blocks. When macrofaunas are scarce or absent the conodont zonation provides an alternative to one based on macrofauna only. It has been used effectively in assessing previous zonal determinations based on macrofauna.Conodonts of the Magdalen Islands are dominated by Clydagnathus, Cavusgnathus, Mestognathus, and Taphrognathus, all asymmetric cavusgnathiform genera. This dominance, the total lack of Gnathodus, abundant sulphates and chlorides, as well as foraminiferal and algal evidence, suggest that Lower Carboniferous conodonts of the Magdalen Islands lived in shallow-water shelf environments under conditions of fluctuating salinity.

Stone rosettes as indicators of ancient shorelines: examples from the Precambrian Belcher Group, Northwest Territories

1979 ◽  
Vol 16 (9) ◽  
pp. 1887-1891 ◽  
Author(s):  
B. D. Rlcketts ◽  
J. A. Donaldson
Keyword(s):  
Shallow Water ◽  
Northwest Territories ◽  
Close Packing ◽  
Desiccation Cracks ◽  
Cross Bedding ◽  
Vertical Arrays ◽  
Water Origin ◽  
Shallow Subtidal ◽  
Shore Platforms

Flat-pebble conglomerates in the McLeary Formation of the Belcher Group display close packing of intraformational slabs in near-vertical arrays that appear distinctively polygonal in sections parallel to bedding. Such arrangements of flat pebbles, known by names such as stone rosettes and slone packings, are common on modem beaches, especially within the swash and backwash zone of shore platforms. Association of the McLeary stone rosettes with sedimentary features suggestive of shallow subtidal to supratidal origin (herringbone cross-bedding, reactivation surfaces, desiccation cracks, tepee structures, gypsum casts, oncolites, stromatolites, and probable beachrock) supports a hydrodynamic origin for these polygonal arrays of flat pebbles, an origin that has been demonstrated for modern occurrences. Where associated structures corroborate interpretation of a shallow-water origin, such stone rosettes provide evidence for ancient strandlines, and the designation "beach rosettes" is suggested as appropriate to distinguish them from stone rosettes formed by periglacial processes.

Conodont biostratigraphy and paleoecology of Middle Ordovician rocks in eastern Oklahoma

1989 ◽  
Vol 63 (1) ◽  
pp. 92-107 ◽  
Author(s):  
Jeffrey A. Bauer
Keyword(s):  
New Species ◽  
Conodont Biostratigraphy ◽  
Middle Ordovician ◽  
Two New Species ◽  
Shallow Subtidal ◽  
Conodont Fauna ◽  
Carbonate Deposits

Conodonts from the upper Burgen, Tyner, and Fite Formations (Middle Ordovician) of eastern Oklahoma include two new species, Phragmodus harrisi and Plectodina tynerensis. The conodont fauna indicates that the upper Burgen through middle Tyner is Whiterockian (pre- to earliest Chazyan) and that the upper Tyner–Fite is probably Kirkfieldian in age.The Whiterockian Burgen–Tyner preserves a regressive succession of shoreface, lagoonal, and intertidal deposits. That change is reflected by the conodont succession, which shows replacement of a fauna dominated by species of Neomultioistodus, Scandodus?, and Paraprioniodus by one dominated by species of Phragmodus, Plectodina, and Erismodus.Carbonate deposits of the Kirkfieldian(?) upper Tyner and Fite Formations follow a major hiatus and reflect shallow, subtidal to intertidal conditions. The conodont fauna is composed of species of Aphelognathus, Plectodina, Curtognathus, Erismodus, and Oulodus, among others.

Trilobites, biostratigraphy, and lithostratigraphy of the Crepicephalus and Aphelaspis zones, lower Deadwood Formation (Marjuman and Steptoean stages, Upper Cambrian), Black Hills, South Dakota

2000 ◽  
Vol 74 (2) ◽  
pp. 199-223 ◽  
Author(s):  
James H. Stitt ◽  
Patrick J. Perfetta
Keyword(s):  
New Species ◽  
North America ◽  
South Dakota ◽  
Shallow Water ◽  
Black Hills ◽  
Strong Preference ◽  
Upper Cambrian ◽  
Shallow Subtidal ◽  
Intrashelf Basin ◽  
One New Species

Trilobites assigned to 25 genera and 39 species are reported from the Crepicephalus Zone (Marjuman Stage) and Aphelaspis Zone (Steptoean Stage) in the lower part of the Deadwood Formation in the Black Hills of South Dakota. Six taxa are left in open nomenclature, and one new species, Glaphyraspis newtoni, is described.Analysis of the lithologies for this interval from the best exposed measured sections on a southeast-northwest transect reveal a nearshore, shallow subtidal, siliciclastic dominated environment to the southeast, succeeded offshore by a shallow subtidal to lowest intertidal carbonate shoal environment, and then a transitional shaly limestone interval into a more shaly distal intrashelf basin to the northwest.Specimens of species of Coosia, Crepicephalus, Tricrepicephalus, Kingstonia, Pseudagnostina, and Coosina comprise more than 75 percent of the fauna of the Crepicephalus Zone. Coosina ariston, Crepicephalus snowyensis, Tricrepicephalus tripunctatus, Arcuolimbus convexus, and some species of Blountia had a strong preference for the shallow-water siliciclastic facies present in the southeastern sections closest to the paleoshoreline. Crepicephalus rectus, Tricrepicephalus coria, Agnostogonus, cf. A. incognitus and the genera Coosella and Uncaspis preferred the farther offshore, deeper-water, shaly intershelf basin located in the northern Black Hills. Trilobites from the Crepicephalus Zone are used to correlate the lower part of the Deadwood Formation with coeval strata elsewhere in North America.

The lowermost Silurian of Jämtland, central Sweden: conodont biostratigraphy, correlation and biofacies

2005 ◽  
Vol 96 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Peter Dahlqvist ◽  
Stig M. Bergström
Keyword(s):  
North America ◽  
Shallow Water ◽  
Late Ordovician ◽  
Conodont Biostratigraphy ◽  
Conodont Biofacies ◽  
The One ◽  
First Time ◽  
Regional Review

ABSTRACTThe Late Ordovician–Early Silurian succession in Jämtland includes the marine Kogsta Siltstone, which is unconformably overlain by the shallow-water Ede Quartzite that grades into the open-marine Berge Limestone. A Hirnantia shelly fauna dates the uppermost Kogsta Siltstone as Hirnantian, and shelly fossils indicate an Aeronian age for the Berge Limestone. Biostratigraphically highly diagnostic conodonts of the early-middle Aeronian Pranognathus tenuis Zone provide the first firm date of the Upper Ede Quartzite and the lowermost Berge Limestone. The Lower Ede Quartzite has not yielded fossils, but sedimentological data suggest it to be of Hirnantian age and reflect the glacio-eustatic low-stand. The contact between the Lower and Upper Ede Quartzite, here taken to be the Ordovician–Silurian boundary, appears to be an unconformity associated with a stratigraphic gap that at least includes the Rhuddanian Stage. The biostratigraphically important conodonts Pranognathus tenuis, Kockelella? manitoulinensis, and Pranognathus siluricus are recorded from Sweden for the first time, and these and other conodonts are used for correlations with coeval units in Europe and North America. In a regional review of Aeronian conodont faunas, three intergrading, apparently depth-related, conodont biofacies are recognised, the Jämtland conodonts representing the one characteristic of the shallowest water.

Carboniferous conodont biostratigraphy

2020 ◽  
pp. SP512-2020-38
Author(s):  
James E. Barrick ◽  
Alexander S. Alekseev ◽  
Silvia Blanco-Ferrera ◽  
Natalia V. Goreva ◽  
Keyi Hu ◽  
...  
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Global Distribution ◽  
High Quality ◽  
Conodont Biostratigraphy ◽  
Conodont Biofacies ◽  
Extinction Event ◽  
Water Facies

AbstractCarboniferous conodont biostratigraphy comprises regional zonations that reflect the paleogeographic distribution of taxa and distinct shallow-water and deep-water conodont biofacies. Some species have a global distribution and can effect high quality correlations. These taxa are incorporated into definitions of global Carboniferous chronostratigraphic units. A standard global Carboniferous zonation has not been developed. The lowermost Mississippian is zoned by Siphonodella species, except in shallow-water facies, where other polygnathids are used. Gnathodus species radiated during the Tournaisian and are used to define many Mississippian zones. A late Tournaisian maximum in diversity, characterized by short-lived genera, was followed by lower diversity faunas of Gnathodus species and carminate genera through the Viséan and Serpukhovian. By the late Viséan and Serpukhovian, Lochriea provides better biostratigraphic resolution. Shallow-water zonations based on Cavusgnathus and Mestognathus are difficult to correlate. An extinction event near the base of the Pennsylvanian was followed by the appearance of new gnathodid genera: Rhachistognathus, Declinognathodus, Neognathodus, Idiognathoides, and Idiognathodus. By the middle of the Moscovian, few genera remained: Idiognathodus, Neognathodus and Swadelina. During the middle Kasimovian and Gzhelian, only Idiognathodus and Streptognathodus species were common. Near the end of the Gzhelian, a rediversification of Streptognathodus species extended into the Cisuralian.

Early Cambrian Trilobites from the Shackleton Limestone of the Central Transantarctic Mountains

1995 ◽  
Vol 69 (S45) ◽  
pp. 1-28 ◽  
Author(s):  
Allison R. Palmer ◽  
Albert J. Rowell
Keyword(s):  
New Species ◽  
Shallow Water ◽  
Geographic Distribution ◽  
Lower Cambrian ◽  
New Genus ◽  
Early Cambrian ◽  
Large Measure ◽  
Shallow Subtidal ◽  
Water Carbonate ◽  
Shallow Water Carbonate

We document and describe the trilobite faunas of the Lower Cambrian Shackleton Limestone. The faunas include taxa of Atdabanian, Botomian and possible Toyonian ages and have affinities with those known previously from Gondwana or peri-Gondwana terranes. The geographic distribution of these organisms reveals a large measure of faunal connectedness around the margin of this vast supercontinent in Early Cambrian time. This connectedness extended even to taxa that inhabited shallow-water carbonate shelf environments, because the Shackleton Limestone accumulated in a variety of shallow subtidal and peritidal settings along the ocean-facing margin of the East Antarctic craton, subsequent to a Neoproterozoic rifting event. Although the fossilized Shackleton Limestone fauna is dominated by archaeocyathans, trilobites are common locally. We describe the remains of 35 trilobite taxa from 32 collecting localities. One species,H. granulosa, is assigned to the new genusHolyoakia;the remaining new species arePagetides (Discomesites) spinosus, Lemdadella antarcticae, Kingaspis(?)convexus, Yunnanocephalus longioccipitalis, andOnchocephalina(?)spinosa.

scholarly journals Paleogeographic significance of Upper Triassic basinal succession of the Tamar Valley, northern Julian Alps (Slovenia)

2015 ◽  
Vol 66 (4) ◽  
pp. 269-283 ◽  
Author(s):  
Luka Gale ◽  
Bogomir Celarc ◽  
Marcello Caggiati ◽  
Tea Kolar-Jurkovšek ◽  
Bogdan Jurkovšek ◽  
...  
Keyword(s):  
Shallow Water ◽  
Southern Alps ◽  
Upper Triassic ◽  
Santo Stefano ◽  
Dolomia Principale ◽  
Julian Alps ◽  
Shallow Subtidal ◽  
Platform Carbonates ◽  
Slovenian Basin ◽  
Marly Limestone

AbstractThe Julian Alps (western Slovenia) structurally belong to the eastern Southern Alps. The Upper Triassic succession mostly consists of shallow water platform carbonates of the Dolomia Principale-Dachstein Limestone system and a deep water succession of the Slovenian Basin outcropping in the southern foothills of the Julian Alps. In addition to the Slovenian Basin, a few other intraplatform basins were present, but they remain poorly researched and virtually ignored in the existing paleogeographic reconstructions of the eastern Southern Alps. Herein, we describe a deepening-upward succession from the Tamar Valley (north-western Slovenia), belonging to the Upper Triassic Tarvisio Basin. The lower, Julian-Tuvalian part of the section comprises peritidal to shallow subtidal carbonates (Conzen Dolomite and Portella Dolomite), and an intermediate carbonate-siliciclastic unit, reflecting increased terrigenous input and storm-influenced deposition (Julian-lowermost Tuvalian shallow-water marlstone and marly limestone of the Tor Formation). Above the drowning unconformity at the top of the Portella Dolomite, Tuvalian well-bedded dolomite with claystone intercalations follows (Carnitza Formation). The latter gradually passes into the uppermost Tuvalian–lowermost Rhaetian bedded dolomite with chert and slump breccias, deposited on a slope and/or at the toe-of-slope (Bača Dolomite). Finally, basinal thin-bedded bituminous limestone and marlstone of Rhaetian age follow (Frauenkogel Formation). The upper part of the Frauenkogel Formation contains meter-scale platform-derived limestone blocks, which are signs of platform progradation. The Tarvisio Basin may have extended as far as the present Santo Stefano di Cadore area, representing a notable paleogeographic unit at the western Neotethys margin.

Conodont biostratigraphy of Tournaisian shallow-water carbonates in central Guangxi, South China

Geobios ◽  
2014 ◽  
Vol 47 (6) ◽  
pp. 389-401 ◽  
Author(s):  
Wenkun Qie ◽  
Xionghua Zhang ◽  
Yuansheng Du ◽  
Bing Yang ◽  
Wenting Ji ◽  
...  
Keyword(s):  
Shallow Water ◽  
South China ◽  
Conodont Biostratigraphy
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