Cambrian trilobites from Brzechów, Holy Cross Mountains (Poland) and their significance in stratigraphic correlation and biogeographic reconstructions

2007 ◽  
Vol 144 (4) ◽  
pp. 661-686 ◽  
Author(s):  
ANNA ŻYLIŃSKA ◽  
MONIKA MASIAK

A revision of the trilobite fauna from Brzechów in the Holy Cross Mountains (Poland) shows that the assemblage consists of Palaeolenus medius (Bednarczyk), Issafeniella orlowinensis (Samsonowicz), Kingaspidoides sanctacrucensis (Czarnocki), Paradoxides (Acadoparadoxides) oelandicus Sjögren, P. (A.) cf. mureroensis Sdzuy and P. (A.) sp. It is earliest Middle Cambrian in age according to the West Gondwana standard of Geyer & Landing (2004) and can be correlated with the Cephalopyge notabilis Zone of Morocco. Moreover, the co-occurrence of the ranges of P. (A.) oelandicus with P. (A.) cf. mureroensis might suggest that P. (A.) oelandicus appears earlier in the Brzechów sandstones than in Scandinavia, thus the strata exposed here do not find their correlative in the Scandinavian succession. As a result, the Banian/Agdzian boundary (Lower–Middle Cambrian boundary according to the West Gondwana standard) probably lies within the Kamieniec Formation, and also below the Brzechów sandstones, in the upper part of the Ociesęki Formation. Close similarity of the discussed assemblage with contemporaneous assemblages from Morocco, Jordan or New Brunswick indicates that the fauna is generally of peri-Gondwanan and Gondwanan aspect.

2000 ◽  
Vol 74 (5) ◽  
pp. 858-878 ◽  
Author(s):  
Stephen R. Westrop ◽  
Ed Landing

The Hanford Brook Formation, one of the classic Cambrian units of Avalonian North America, contains at least eight species of endemic trilobites, including Berabichia milleri Westrop n. sp., that are assigned to seven genera. The vertical succession of faunas is far more complex than has been recognized previously, with each member containing a lithofacies-specific assemblage. These are, in ascending order: a bradoriid-linguloid Association without trilobites in the nearshore St. Martin's Member, a Protolenus Association in dysaerobic siltstones and sandstones of the Somerset Street Member, and a Kingaspidoides-Berabichia Association in hummocky cross-stratified sandstones of the Long Island Member that overlie a parasequence boundary at Hanford Brook. Due to the breakdown of biogeographic barriers in the late Early Cambrian, two new species-based zones, the Protolenus elegans and Kingaspidoides cf. obliquoculatus zones, share trilobite genera with the Tissafinian Stage of Morocco. This generic similarity has been the basis for correlation of this upper Lower Cambrian interval on the Avalon continent with the West Gondwanan lowest Middle Cambrian. However, the clear facies control on the occurrence of genera in the Hanford Brook Formation and the presence of an abrupt faunal break and unconformity at the base of the Tissafinian in Morocco makes this correlation questionable. The Hanford Brook Formation may represent a late Early Cambrian interval unknown in Gondwana. Sequence-stratigraphic criteria even raise the possibility that the Protolenus Association is the biofacies equivalent of Callavia broeggeri Zone faunas of the Brigus Formation of Newfoundland, Nova Scotia and Massachusetts.


2018 ◽  
Vol 156 (06) ◽  
pp. 1027-1051 ◽  
Author(s):  
JAKUB NOWICKI ◽  
ANNA ŻYLIŃSKA

AbstractTwo hundred and eighty specimens of paradoxidids from two localities in the Holy Cross Mountains (Poland) have been reanalysed using morphometric techniques. Revision of the dataset provided evidence for the presence of two endemic taxa: Acadoparadoxides kozlowskii (Orłowski, 1959) and Acadoparadoxides samsonowiczi (Orłowski, 1959), both belonging to the earliest group of Acadoparadoxides, initially considered to be present only in Gondwanan successions. Thus, this is the first description of the members of this group outside West Gondwana. The taxonomic revision, and the presence of representatives of the earliest acadoparadoxidines coupled with the absence of taxa typical of Scandinavia that were previously described from this locality have resulted in the modification of the biostratigraphic scheme hitherto used in the Holy Cross Mountains. The newly established A. samsonowiczi – A. kozlowskii Assemblage Zone is correlated with the Morocconus notabilis Zone of Morocco, and thus represents the Cambrian Series 2 and 3 boundary interval. Links with West Gondwana challenge the existing palaeogeographic interpretations for the southern part of the Holy Cross Mountains and point to an urgent need to revise the position of the Małopolska Block during the middle Cambrian.


1988 ◽  
Vol 25 (5) ◽  
pp. 669-690 ◽  
Author(s):  
Saifullah K. Tanoli ◽  
Ron K. Pickerill

The Cambrian – Lower Ordovician Saint John Group of the Saint John area, southern New Brunswick, has historically been subdivided into 11 formations. The existing scheme is inappropriate, however, as many of the supposed formations, particularly those of Middle Cambrian–Early Ordovician age, were distinguished on a biostratigraphic rather than lithostratigraphic basis. We suggest the sequence can be more appropriately subdivided into seven formations, each of which can be clearly and easily identified by the field geologist. Lower Cambrian formations comprise, from base to top, the Ratcliffe Brook, Glen Falls, and Hanford Brook formations, all of which are retained from the previous nomenclature. Middle Cambrian strata comprise the Forest Hills Formation (to replace the Fossil Brook and Porter Road formations) and Upper Cambrian strata the King Square Formation (to replace the Hastings Cove and Agnostus Cove formations) and Silver Falls Formation (to replace the Black Shale Brook and Narrows formations). Lower Ordovician strata are referred to as the Reversing Falls Formation (to replace the Navy Island and Suspension Bridge formations). Descriptions of each formation are given, major sections of each are included, and stratigraphic correlation of the sequence in different geographic areas is demonstrated.


1985 ◽  
Vol 22 (6) ◽  
pp. 881-892 ◽  
Author(s):  
John D. Greenough ◽  
S. R. McCutcheon ◽  
V. S. Papezik

Lower to Middle Cambrian volcanic rocks occur within the Avalon Zone of southern New Brunswick at Beaver Harbour and in the Long Reach area. The Beaver Harbour rocks are intensely altered, but the major- and trace-element geochemistry indicates that they could be highly evolved (basaltic andesites) within-plate basalts. The mafic flows from the Long Reach area form two chemically and petrologically distinct groups: (1) basalts with feldspar phenocrysts that represent evolved continental tholeiites with some oceanic characteristics; and (2) a group of aphyric basalts showing extremely primitive continental tholeiite compositions, also with oceanic affinities and resembling some rift-related Jurassic basalts on the eastern seaboard. Felsic pyroclastic rocks in the Long Reach area make the suite bimodal. This distribution of rock types supports conclusions from the mafic rocks that the area experienced tension throughout the Early to Middle Cambrian.


1982 ◽  
Vol 114 (4) ◽  
pp. 349-357 ◽  
Author(s):  
D. P. Peschken ◽  
D. B. Finnamore ◽  
A. K. Watson

AbstractThe gall fly Urophora cardui (L.) (Diptera: Tephritidae), native to Europe, was released at 24 locations across Canada beginning in 1974. It became established in Ontario, Quebec, and New Brunswick but died out in all but one location in western Canada. Evidence for winter mortality in the west does not explain the failure of these colonies. Although galls, in particular those on the main shoot, reduce the height of Canada thistle, so far the impact on the host weed, Canada thistle (Cirsium arvense) (L.) Scop., is slight.


1991 ◽  
Vol 28 (7) ◽  
pp. 1121-1130 ◽  
Author(s):  
Michel Villeneuve ◽  
Jean-Jacques Cornée

Paleogeographic reconstructions of Paleozoic time are presented for the northwest margin of the West-African Craton. An extensional regime and a marine transgression were dominant during the Early Cambrian. During the Middle Cambrian, the Rokélides orogen was responsible for the sea regression to the south, while the proto-Atlantic opening was active to the north of the Reguibat shield. A large stable marine platform was present during Early and Middle Ordovician. A general regression and the formation of the West-African Inlandsis took place during the Late Ordovician. During Silurian time, this sea transgressed over most of the African platform. Incipient Hercynian deformations during the Early Devonian produced horsts and grabens in Morocco. At the end of the Devonian and the beginning of the Carboniferous, the sea was restricted to isolated basins and tectonic trenches. Collision between West Africa and North America during the Late Carboniferous transformed the Lower Paleozoic margin into an Hercynian orogenic belt, whose structure is controlled by the presence of crustal blocks, generated as early as the Cambrian, and probably reflecting, in turn, older Panafrican zones of weakness. [Translated by the Journal]


Geology ◽  
2020 ◽  
Vol 48 (5) ◽  
pp. 441-445 ◽  
Author(s):  
F.A. Sundberg ◽  
K.E. Karlstrom ◽  
G. Geyer ◽  
J.R. Foster ◽  
J.W. Hagadorn ◽  
...  

Abstract Trilobites appeared and diversified rapidly in the Cambrian, but it is debated as to whether their radiations and extinctions were globally synchronous or geographically restricted and diachronous. The end of the early Cambrian is a classic example—it has traditionally been defined by the extinction of olenellid and redlichiid trilobites and the appearance of paradoxidid trilobites. Here we integrate the global biostratigraphy of these three trilobite groups with high-precision tuff and tandem detrital zircon U-Pb age constraints to falsify prior models for global synchronicity of these events. For the first time, we demonstrate that olenellid trilobites in Laurentia went extinct at least 3 Ma after the first appearance of paradoxidids in Avalonia and West Gondwana (ca. 509 Ma). They also disappeared before the extinction of redlichiids and prior to the base of the Miaolingian at ca. 506 Ma in South China. This indicates that these three trilobite groups (paradoxidids, olenellids, and redlichiids) and their associated biotas overlapped in time for nearly 40% of Cambrian Epoch 2, Age 4. Implications of this chronological overlap are: (1) trilobite transitions were progressive and geographically mediated rather than globally synchronous; and (2) paleontological databases underestimate the diversity of the early Cambrian. This ∼3 Ma diachroneity, at a critical time in the early evolution of animals, also impacts chemostratigraphic and paleoclimatic data sets that are tied to trilobite biostratigraphy and that collectively underpin our understanding of the Cambrian Earth system.


1949 ◽  
Vol 6 (02) ◽  
pp. 197-207
Author(s):  
Roscoe R. Hill

John Lloyd Stephens was a remarkable man in his day and probably would have been remarkable at any time in American history. Lawyer, politician, traveler, author, diplomat and entrepreneur, he made his contribution to American life. Because of the heritage which he left, now as the centenary of his death approaches, the presses of two leading American universities have enriched their list of titles with books relating to Stephens. Rutgers University Press, located in Stephens’ native state, has brought out a new edition of Incidents of Travel in Central America, Chiapas, & Yucatan (New Brunswick, 1949. 2 vols., Pp. xx, 346; xiv, 340. Illus., map.) under the able editorship of Richard L. Predmore. In the West, the University of Oklahoma Press has offered to the reading public Maya Explorer: John Lloyd Stephens and the Lost Cities of Central America and Yucatan (Norman, 1948. Pp. xviii, 324., illus.), a delightful biography by Victor Wolfgang von Hagen.


2017 ◽  
Vol 155 (7) ◽  
pp. 1566-1595 ◽  
Author(s):  
J. JAVIER ÁLVARO ◽  
JORGE ESTEVE ◽  
SAMUEL ZAMORA

AbstractA Cambrian immigration event of paradoxidid trilobites has traditionally marked some regional lower–middle Cambrian boundaries in the Acado-Baltic subprovince (including Baltica and the Mediterranean and Avalonian margins of West Gondwana). The earliest paradoxidine species in Morocco and the Iberian Peninsula have been used as a chronostratigraphic link to support the definition of a common base for the Cambrian Series 3, but recent studies have proposed new species without revising previously established ones. This paper offers a morphological statistical analysis based on both linear measurement and landmark-based geometric morphometric approaches performed on the earliest paradoxinine trilobites sampled in the Anti-Atlas (Morocco) and the Iberian Chains (Spain). As a result, the diagnosis of Acadoparadoxides mureroensis is emended and several species recently erected in Morocco (A. cf. mureroensis, A. levisettii, A. ovatopyge and A. pampalius) are suggested as synonyms of A. mureroensis until 3D statistical analyses are available based on material preserved on carbonate or silica nodules. The first appearance of A. mureroensis in both areas can be provisionally used for regional correlation until homotaxic tests are checked.


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