scholarly journals New occurrences of Palaeopascichnus from the Stáhpogieddi Formation, Arctic Norway, and their bearing on the age of the Varanger Ice Age

2018 ◽  
Vol 55 (11) ◽  
pp. 1253-1261 ◽  
Author(s):  
Sören Jensen ◽  
Anette E.S. Högström ◽  
Magne Høyberget ◽  
Guido Meinhold ◽  
Duncan McIlroy ◽  
...  
Keyword(s):  
South Australia ◽  
Trace Fossils ◽  
Ice Age ◽  
Major Break ◽  
Age Range ◽  
New Occurrences

We report on new occurrences of the late Ediacaran problematicum Palaeopascichnus (Protista?) from the Stáhpogieddi Formation, Arctic Norway. The stratigraphically lowest occurrences are in beds transitional between the Lillevannet and Indreelva members: the highest in the second cycle of the Manndrapselva Member, stratigraphically close to the lowest occurrences of Cambrian-type trace fossils. This establishes a long stratigraphical range of Palaeopascichnus on the Digermulen Peninsula, as has been previously documented from Newfoundland, South Australia, and elsewhere in Baltica. The age range of Palaeopascichnus in Avalonia and Baltica is from ∼565 to 541 Ma. Since the transition from the Mortensnes Formation to the Stáhpogieddi Formation is without a major break in sedimentation, this supports the inference that the underlying glacigenic Mortensnes Formation is ca. 580 Ma, and therefore Gaskiers-equivalent, or younger.

New occurrences of Oldhamia and other trace fossils in the Cambrian of the Yukon and Ellesmere Island, arctic Canada

1994 ◽  
Vol 31 (5) ◽  
pp. 767-782 ◽  
Author(s):  
H. J. Hofmann ◽  
M. P. Cecile ◽  
L. S. Lane
Keyword(s):  
North America ◽  
Western Europe ◽  
Trace Fossils ◽  
Trace Fossil ◽  
Ellesmere Island ◽  
Early Cambrian ◽  
Arctic Canada ◽  
North Central ◽  
Middle Cambrian ◽  
New Occurrences

Trace fossil assemblages from green and maroon argillites at 34 localities in the British Mountains and Barn Mountains of northernmost Yukon, and 3 localities in the Grant Land Formation of northern Ellesmere Island contain abundant Planolites spp., Oldhamia curvata, Oldhamia flabellata, and Oldhamia radiata, and rare Oldhamia antiqua, Oldhamia? wattsi (n.comb.), Bergaueria hemispherica, Cochlichnus sp., Didymaulichnus? sp., Helminthoidichnites sp., Monomorphichnus sp., Protopaleodictyon sp., and Tuberculichnus? sp. Additionally, 11 new sites in the Selwyn Mountains of north-central Yukon have yielded an ichnofauna including Helminthorhaphe sp., O. curvata, O. flabellata, O. radiata, Plagiogmus? sp., Planolites spp., and unidentified small hemispherical traces. All these assemblages are interpreted as Early Cambrian to early Middle Cambrian, based on comparison with Oldhamia-bearing ichnofaunas of similar age in North America, Argentina, and western Europe, and on archaeocyathids and olenellids in overlying units.

Vertebrate Trace Fossils from the Late Pleistocene of Kangaroo Island, South Australia

Ichnos ◽  
2017 ◽  
Vol 25 (2-3) ◽  
pp. 232-251 ◽  
Author(s):  
Aaron B. Camens ◽  
Stephen P. Carey ◽  
Lee J. Arnold
Keyword(s):  
Late Pleistocene ◽  
South Australia ◽  
Trace Fossils

Ediacaran events: boundary relationships and correlation of key sections, especially in ‘Armorica’

1984 ◽  
Vol 121 (6) ◽  
pp. 635-643 ◽  
Author(s):  
R. J. F. Jenkins
Keyword(s):  
Southern Africa ◽  
North Atlantic ◽  
South Australia ◽  
Trace Fossils ◽  
Faecal Pellets ◽  
Late Precambrian ◽  
Flinders Ranges ◽  
Northern Russia ◽  
Body Fossil ◽  
Radiometric Data

AbstractThe transitional interval between the Adelaidean and Ediacaran systems in the central Flinders Ranges, South Australia, comprises mainly basinal sediments, with some tuff beds (Bunyeroo Formation) and a widespread thin dolomite bed which apparently evidences a brief regressive episode (base of Wonoka Formation). Body imprints of metazoans, trace fossils and probable faecal pellets are present at various levels in the Ediacaran succession. Comparable assemblages occurring in key successions in southern Africa, northern Russia, Siberia, Newfoundland and England promise a global biostratigraphy. One Ediacaran body fossil occurs in the Yangtze Gorges section, China. Analysis of abundant late Precambrian radiometric data for the present North Atlantic margins suggests that the Ediacaran may be dated between about 590 Ma and ~ 545–540 Ma.

Spatial variation in size and age structures and reproductive characteristics of the King George whiting (Percoidei : Sillaginidae) in South Australian waters

2000 ◽  
Vol 51 (1) ◽  
pp. 11 ◽  
Author(s):  
A. J. Fowler ◽  
L. McLeay ◽  
D. A. Short
Keyword(s):  
Gonad Development ◽  
South Australia ◽  
Size Distributions ◽  
Age Classes ◽  
Habitat Types ◽  
Histological Techniques ◽  
Geographic Regions ◽  
High Wave Energy ◽  
Age Range ◽  
Age Structures

Adult King George whiting were sampled at 12 localities representing a range of habitat types across South Australia. Sampling was undertaken between March and May for a minimum of 2 years between 1995 and 1998. Fish were aged by otolith interpretation, and reproductive maturity was determined by gonad analysis using macroscopic and histological techniques. In total, 6961 fish comprising 3678 females and 3283 males were considered from four localities in each of three geographic regions. In both Gulf St Vincent and Spencer Gulf, age structures became more complex from north to south, associated with a shift in size towards larger fish. In the simplest age structures, >90% of fish were from the 3-year age class, whereas the age range of the most complex was 3–17 years, with the 3–5 age classes most numerous. Males were more abundant in smaller size classes and females in the larger. Although some fish from each locality showed some gonad development, only at three localities did spawning occur. At these places, populations had the broadest age and size distributions and were in deep water that experienced medium to high wave energy. Since spawning grounds and nursery areas are up to several hundred kilometres apart, the processes of larval advection and adult movement are implicated as obligate processes of the life history.

Genetic structure of yellow cedar (Chamaecyparis nootkatensis)

2001 ◽  
Vol 79 (7) ◽  
pp. 822-828 ◽  
Author(s):  
Carol Ritland ◽  
Terry Pape ◽  
Kermit Ritland
Keyword(s):  
Genetic Structure ◽  
Gene Diversity ◽  
Species Conservation ◽  
Ice Age ◽  
North Coast ◽  
Evolutionary Divergence ◽  
Southeast Alaska ◽  
Chamaecyparis Nootkatensis ◽  
Inbreeding Coefficients ◽  
Age Range

A range-wide survey of isozyme variation in yellow cedar (Chamaecyparis nootkatensis (D. Don) Spach; or Alaska cedar) found significant inbreeding and a striking geographical structure. The proportion of diversity among populations (GST) was 0.139, and three major geographical groups were evident: (1) Vancouver Island - mid-north coast British Columbia (B.C.); (2) south coast B.C. - Washington state; (3) southeast Alaska. This may indicate the presence of multiple refugia during ice-age range contractions. Geographically disjunct populations in Oregon and southeastern B.C. were also genetically distinct. Adult inbreeding coefficients (F) were usually positive but varied widely among populations, as did gene diversity. The overall average of F = 0.18 suggests that considerable selfing (ca. 30%) occurs in this species. Other statistics were more typical for a conifer: within population heterozygosity (HS) averaged 0.148, total gene diversity (HT) was 0.171, and the number of alleles per locus and percentage polymorphic loci averaged 1.68 and 50, respectively. This geographic structure has implications for species conservation and for breeding programs. Also, previous studies of other Cupressoideae (Rich. ex Sweet) species indicate that these levels of inbreeding and population structure are not uncommon, and may influence evolutionary divergence in the Cupressoideae.Key words: Chamaecyparis nootkatensis, yellow cedar, genetic structure, inbreeding, phylogeography, isozymes.

Problematica, trace fossils, and tubes within the Ediacara Member (South Australia): redefining the ediacaran trace fossil record one tube at a time

2011 ◽  
Vol 85 (2) ◽  
pp. 256-265 ◽  
Author(s):  
Aaron Sappenfield ◽  
Mary L. Droser ◽  
James G. Gehling
Keyword(s):  
Fossil Record ◽  
South Australia ◽  
Trace Fossils ◽  
Information Structures ◽  
Common Component ◽  
The Past ◽  
Morphological Criteria ◽  
New Perspective ◽  
Body Fossil ◽  
Hand Sample

Ediacaran trace fossils are becoming an increasingly less common component of the total Precambrian fossil record as structures previously interpreted as trace fossils are reinterpreted as body fossils by utilizing qualitative criteria. Two morphotypes, Form E and Form F of Glaessner (1969), interpreted as trace fossils from the Ediacara Member of the Rawnsley Quartzite in South Australia are shown here to be body fossils of a single, previously unidentified tubular constructional morphology formally described herein as Somatohelix sinuosus n. gen. n. sp. S. sinuosus is 2-7 mm wide and 3-14 cm long and is preserved as sinusoidal casts and molds on the base of beds. Well-preserved examples of this fossil preserve distinct body fossil traits such as folding, current alignment, and potential attachment to holdfasts. Nearly 200 specimens of this fossil have been documented from reconstructed bedding surfaces within the Ediacara Member. When viewed in isolated hand sample, many of these specimens resemble ichnofossils. However, the ability to view large quantities of reassembled and successive bedding surfaces within specific outcrops of the Ediacara Member provides a new perspective, revealing that isolated specimens of rectilinear grooves on bed bases are not trace fossils but are poorly preserved specimens of S. sinuosus. Variation in the quality and style of preservation of S. sinuosus on a single surface and the few distinct characteristics preserved within this relatively indistinct fossil also provides the necessary data required to define a taphonomic gradient for this fossil. Armed with this information, structures which have been problematic in the past can now be confidently identified as S. sinuosus based on morphological criteria. This suggests that the original organism that produced this fossil was a widespread and abundant component of the Ediacaran ecosystem.

scholarly journals Obesity and age as factors in leg amputations in fatal motorcycle crashes

2019 ◽  
Vol 60 (1) ◽  
pp. 26-29
Author(s):  
Siobhan O’Donovan ◽  
Corinna van den Heuvel ◽  
Matthew Baldock ◽  
Roger W Byard
Keyword(s):  
Lower Limb ◽  
Motor Vehicle ◽  
South Australia ◽  
Control Group ◽  
Significant Information ◽  
The Road ◽  
The Right ◽  
Lower Leg Amputation ◽  
Leg Amputation ◽  
Age Range

The autopsy files at Forensic Science South Australia were searched over an 11-year period from January 2008 to December 2018 for all cases of motorcycle fatalities in which there had been lower-limb amputations. Six cases were identified, consisting of five male riders and one female pillion passenger. The age range was 48–67 years (average 59 years), which was significantly older than the control group (40.6 years; p < 0.01). All the decedents were overweight, with a body mass index (BMI) of 28.7–43.5 kg/m2 (average 34.9 kg/m2), which again was significantly greater than the control group (28.8 kg/m2; p < 0.05). Five of the incidents involved a collision between a motorcycle and a motor vehicle; the remaining case involved a collision with a tree. Five of the amputations were on the right side in the motorcycle-vehicle impacts, and they varied in severity from loss of a foot to a hind-quarter amputation. There was a single left lower-leg amputation which occurred during the collision with a tree, which was beside the road on the motorcyclist’s left. This study has shown that motorcyclists at greatest risk of lower-limb/pelvis amputations are older than the average rider with higher BMIs. This may be significant information given the increase in both BMI and age in many populations.

Sedimentology and integrated chronostratigraphy of the lower Heatherdale Shale (Cambrian, stages 2–3), Stansbury Basin, South Australia

2020 ◽  
pp. 1-13
Author(s):  
Feiyang Chen ◽  
Glenn A. Brock ◽  
Marissa J. Betts ◽  
Zhiliang Zhang ◽  
Hao Yun ◽  
...  
Keyword(s):  
Lower Cambrian ◽  
Depositional Environment ◽  
South Australia ◽  
Depositional Environments ◽  
Regional Correlation ◽  
Upper Stage ◽  
Age Range ◽  
Depositional Setting ◽  
Integrated Study ◽  
Major Progress

Abstract Major progress has recently been made regarding the biostratigraphy, lithostratigraphy and isotope chemostratigraphy of the lower Cambrian successions in South Australia, in particular of the Arrowie Basin, which has facilitated robust global stratigraphic correlations. However, lack of faunal and sedimentological data from the lower Cambrian Normanville Group in the eastern Stansbury Basin, South Australia – particularly the transition from the Fork Tree Limestone to the Heatherdale Shale – has prevented resolution of the age range, lithofacies, depositional environments and regional correlation of this succession. Here we present detailed sedimentologic, biostratigraphic and chemostratigraphic data through this transition in the eastern Stansbury Basin. Three lithofacies are identified that indicate a deepening depositional environment ranging from inner-mid-shelf (Lithofacies A and B) to outer shelf (Lithofacies C). New δ13C chemostratigraphic data capture global positive excursion III within the lower Heatherdale Shale. Recovered bradoriid Sinskolutella cuspidata supports an upper Stage 2 (Micrina etheridgei Zone). The combined geochemistry and palaeontology data reveal that the lower Heatherdale Shale is older than previously appreciated. This integrated study improves regional chronostratigraphic resolution and interbasinal correlation, and better constrains the depositional setting of this important lower Cambrian package from the eastern Stansbury Basin, South Australia.

scholarly journals Discovery of the oldest bilaterian from the Ediacaran of South Australia

2020 ◽  
Vol 117 (14) ◽  
pp. 7845-7850 ◽  
Author(s):  
Scott D. Evans ◽  
Ian V. Hughes ◽  
James G. Gehling ◽  
Mary L. Droser
Keyword(s):  
Fossil Record ◽  
Common Ancestor ◽  
South Australia ◽  
Trace Fossils ◽  
Last Common Ancestor ◽  
Ediacara Biota ◽  
Size And Morphology ◽  
Animal Communities ◽  
Critical Link ◽  
Anterior Posterior

Analysis of modern animals and Ediacaran trace fossils predicts that the oldest bilaterians were simple and small. Such organisms would be difficult to recognize in the fossil record, but should have been part of the Ediacara Biota, the earliest preserved macroscopic, complex animal communities. Here, we describeIkaria wariootiagen. et sp. nov. from the Ediacara Member, South Australia, a small, simple organism with anterior/posterior differentiation. We find that the size and morphology ofIkariamatch predictions for the progenitor of the trace fossilHelminthoidichnites—indicative of mobility and sediment displacement. In the Ediacara Member,Helminthoidichnitesoccurs stratigraphically below classic Ediacara body fossils. Together, these suggest thatIkariarepresents one of the oldest total group bilaterians identified from South Australia, with little deviation from the characters predicted for their last common ancestor. Further, these trace fossils persist into the Phanerozoic, providing a critical link between Ediacaran and Cambrian animals.

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