scholarly journals Histology and Geochemistry of Allosaurus (Dinosauria: Theropoda) From the Cleveland-Lloyd Dinosaur Quarry (Late Jurassic, Utah): Paleobiological Implications

2021 ◽  
Vol 9 ◽  
Author(s):  
Christophe Ferrante ◽  
Lionel Cavin ◽  
Torsten Vennemann ◽  
Rossana Martini
Keyword(s):  
Late Jurassic ◽  
Skeletal Maturity ◽  
Upper Jurassic ◽  
Published Data ◽  
Growth Strategies ◽  
Geochemical Composition ◽  
Growth Variability ◽  
Geochemical Study ◽  
Potential Biomarker ◽  
Growth Distribution

The Late Jurassic Allosaurus is one of the better-studied dinosaurs. A histological and geochemical study of a tibia and a femur of A. fragilis recovered in the Upper Jurassic Cleveland-Lloyd Dinosaur Quarry, Utah, United States has been done in order to address growth characteristics of this species. The two bones, probably belonging to separate individuals, are among the largest known for this species, which make them suitable to address such issues. The inclusion of our data on femur growth markings in the previously published data reflects a range of growth variability rather than two distinct growth strategies. The tibia has a well-developed external fundamental system indicating somatic maturity achievement. Using a quantitative method of superimposition to retrocalculate missing lines of arrested growth, the tibia appears to correspond to an individual that reached its skeletal maturity at 22 years and died at approximately 26 years. In the tibia, the concentration of zinc, a potential biomarker associated with bone formation, displays a higher concentration in zones of rapid growth compared to annuli. There is no direct relationship between the values of δ18Op and the lines of arrested growth distribution. The absence of relations between the histological organization and an enrichment in REE of the bone, indicates that the variations of δ18Op likely represent a diagenetic process rather than a primordial, biologic composition. However, the geochemical composition of the bones is not homogeneous along the sections, indicating that the signal variations have not been completely erased by diagenesis.

The Provenance Tectonic Background Analysis of the Upper Jurassic Mohe Basin in Northeast China

2013 ◽  
Vol 734-737 ◽  
pp. 476-479
Author(s):  
Yue Qiao Zhang ◽  
Wei Hou ◽  
Fang Zhang
Keyword(s):  
Continental Margin ◽  
Northeast China ◽  
Late Jurassic ◽  
Active Continental Margin ◽  
Upper Jurassic ◽  
Orogenic Belt ◽  
Island Arc ◽  
Geochemical Composition

The provenance tectonic background of Late Jurassic Mohe Basin was researched through the geochemical composition of sandstone. The Late Jurassic Mohe Basin is characterized by multiple provenances. One provenance is the active continental margin, and another is the island arc. Comparing with the regional lithology, the active continental margin may be from the Mongolia-Okhotsk orogenic belt, and the island arc may be from the northern of the Da Hingan Mountains. The characteristics are concerned with its geotectonic position.

scholarly journals The taphonomy of dinosaurs from the Upper Jurassic of Tendaguru (Tanzania) based on field sketches of the German tendaguru expedition (1909–1913)

Fossil Record ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 25-61 ◽  
Author(s):  
W.-D. Heinrich
Keyword(s):  
Old Age ◽  
Late Jurassic ◽  
Depositional Environment ◽  
Upper Jurassic ◽  
Skeletal Remains ◽  
Time Span ◽  
Post Mortem ◽  
Seasonal Drought ◽  
Long Time

Tendaguru is one of the most important dinosaur localities in Africa. The Tendaguru Beds have produced a diverse Late Jurassic (Kimmeridgian to Tithonian) dinosaur assemblage, including sauropods (<i>Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia</i>), theropods (e.g., <i>Elaphrosaurus, Ceratosaurus, Allosaurus</i>), and ornithischians (<i>Kentrosaurus, Dryosaurus</i>). Contrary to the well studied skeletal anatomy of the Tendaguru dinosaurs, the available taphonomic information is rather limited, and a generally accepted taphonomic model has not yet been established. Assessment of unpublished excavation sketches by the German Tendaguru expedition (1909–1913) document bone assemblages of sauropod and ornithischian dinosaurs from the Middle Saurian Bed, Upper Saurian Bed, and the Transitional Sands above the <i>Trigonia smeei</i> Bed, and shed some light on the taphonomy of the Tendaguru dinosaurs. Stages of disarticulation range from incomplete skeletons to solitary bones, and strongly argue for carcass decay and post-mortem transport prior to burial. The sauropod bone accumulations are dominated by adult individuals, and juveniles are rare or missing. The occurrence of bones in different superimposed dinosaur-bearing horizons indicates that skeletal remains were accumulated over a long time span during the Late Jurassic, and the majority of the bone accumulations are probably attritional. These accumulations are likely to have resulted from long-term bone imput due to normal mortality events caused by starvation, seasonal drought, disease, old age and weakness. The depositional environment of the Middle and Upper Saurian Bed was mainly limnic to brackish in origin, while the palaeoenvironment of the Transitional Sands was marginal marine. <br><br> Tendaguru zählt zu den bedeutendsten Dinosaurier-Lagerstätten Afrikas. Aus den Tendaguru-Schichten sind zahlreiche Skelettreste von Sauropoden (<i>Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia</i>), Theropoden (z.B. <i>Elaphrosaurus, Ceratosaurus, Allosaurus</i>) und Ornithischiern (<i>Kentrosaurus, Dryosaurus</i>) geborgen worden. Sie stammen aus der späten Jura-Zeit (Kimmeridge — Tithon). Während der Skelettbau der Tendagurusaurier gut untersucht ist, wirft die Taphonomie des Sauriervorkommens von Tendaguru noch immer Fragen auf. Unklar ist bislang, wie die enormen Anreicherungen von Dinosaurierknochen in den Tendaguru-Schichten zustandekamen. Unveröffentlichte Grabungsskizzen der Deutschen Tendaguru Expedition (1909–1913) erweitern unsere Kenntnisse über die Taphonomie der Tendagurusaurier. In den ausgewerteten Grabungsskizzen sind Knochenansammlungen von Sauropoden und Ornithischiern aus dem Mittleren und Oberen Sauriermergel sowie aus den Übergangsschichten über der <i>Trigonia smeei</i>-Schicht dokumentiert. Die Lage und der Erhaltungszustand der Funde lassen auf erheblichen Zerfall der Kadaver und post-mortalen Transport von Skelettelementen vor der Einbettung schließen. Das Vorkommen von Saurierknochen in mehreren übereinanderliegenden Profilabschnitten der Tendaguru-Schichten zeigt, daß Skelettreste während der späten Jura-Zeit über einen längeren Zeitraum hinweg akkumuliert wurden. Die Ansammlungen von Skelettresten gehen wahrscheinlich auf „normale” Sterbe-Ereignisse zurück, wie z. B. Verhungern, Verdursten, Kankheit, Altersschwäche und jahreszeitliche Dürre. Als Ablagerungsraum der Mittleren und Oberen Saurierschicht kommt ein küstennaher limnischer, zeitweise wohl auch brackischer Küstenstreifen in Betracht. Die knochenführenden Übergangsschichten unter- und oberhalb der Saurierschichten sind randlich marine Ablagerungen. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.1999.4860020102" target="_blank">10.1002/mmng.1999.4860020102</a>

scholarly journals Detrital zircon geochronology and provenance of the Middle to Late Jurassic Paradox Basin and Central Colorado trough: Paleogeographic implications for southwestern Laurentia

Geosphere ◽  
2021 ◽  
Author(s):  
John I. Ejembi ◽  
Sally L. Potter-McIntyre ◽  
Glenn R. Sharman ◽  
Tyson M. Smith ◽  
Joel E. Saylor ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Detrital Zircon ◽  
Late Jurassic ◽  
Upper Jurassic ◽  
Morrison Formation ◽  
Detrital Zircon Geochronology ◽  
Sediment Dispersal ◽  
Paradox Basin ◽  
Southern Oklahoma ◽  
Trace Elemental

Middle to Upper Jurassic strata in the Paradox Basin and Central Colorado trough (CCT; south­western United States) record a pronounced change in sediment dispersal from dominantly aeolian deposition with an Appalachian source (Entrada Sandstone) to dominantly fluvial deposi­tion with a source in the Mogollon and/or Sevier orogenic highlands (Salt Wash Member of the Morrison Formation). An enigmatic abundance of Cambrian (ca. 527–519 Ma) grains at this prove­nance transition in the CCT at Escalante Canyon, Colorado, was recently suggested to reflect a local sediment source from the Ancestral Front Range, despite previous interpretations that local base­ment uplifts were largely buried by Middle to Late Jurassic time. This study aims to delineate spatial and tem­poral patterns in provenance of these Jurassic sandstones containing Cambrian grains within the Paradox Basin and CCT using sandstone petrog­raphy, detrital zircon U-Pb geochronology, and detrital zircon trace elemental and rare-earth ele­mental (REE) geochemistry. We report 7887 new U-Pb detrital zircon analyses from 31 sandstone samples collected within seven transects in west­ern Colorado and eastern Utah. Three clusters of zircon ages are consistently present (1.53–1.3 Ga, 1.3–0.9 Ga, and 500–300 Ma) that are interpreted to reflect sources associated with the Appalachian orogen in southeastern Laurentia (mid-continent, Grenville, Appalachian, and peri-Gondwanan terranes). Ca. 540–500 Ma zircon grains are anom­alously abundant locally in the uppermost Entrada Sandstone and Wanakah Formation but are either lacking or present in small fractions in the overlying Salt Wash and Tidwell Members of the Morrison Formation. A comparison of zircon REE geochem­istry between Cambrian detrital zircon and igneous zircon from potential sources shows that these 540–500 Ma detrital zircon are primarily magmatic. Although variability in both detrital and igneous REE concentrations precludes definitive identifica­tion of provenance, several considerations suggest that distal sources from the Cambrian granitic and rhyolitic provinces of the Southern Oklahoma aulacogen is also likely, in addition to a proximal source identified in the McClure Mountain syenite of the Wet Mountains, Colorado. The abundance of Cambrian grains in samples from the central CCT, particularly in the Entrada Sandstone and Wana­kah Formation, suggests northwesterly sediment transport within the CCT, with sediment sourced from Ancestral Rocky Mountains uplifts of the southern Wet Mountains and/or Amarillo-Wichita Mountains in southwestern Oklahoma. The lack of Cambrian grains within the Paradox Basin sug­gests that the Uncompahgre uplift (southwestern Colorado) acted as a barrier to sediment transport from the CCT.

scholarly journals On a remarkable new species of <i>Tharsis</i>, a Late Jurassic teleostean fish from southern Germany: its morphology and phylogenetic relationships

Fossil Record ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 1-23 ◽  
Author(s):  
Gloria Arratia ◽  
Hans-Peter Schultze ◽  
Helmut Tischlinger
Keyword(s):  
New Species ◽  
Late Jurassic ◽  
Strong Support ◽  
Sister Group ◽  
Common Species ◽  
Upper Jurassic ◽  
Morphological Characters ◽  
Morphological Description ◽  
Sister Group Relationship ◽  
Southern Germany

Abstract. A complete morphological description, as preservation permits, is provided for a new Late Jurassic fish species (Tharsis elleri) together with a revision and comparison of some morphological features of Tharsis dubius, one of the most common species from the Solnhofen limestone, southern Germany. An emended diagnosis of the genus Tharsis – now including two species – is presented. The new species is characterized by a combination of morphological characters, such as the presence of a complete sclerotic ring formed by two bones placed anterior and posterior to the eye, a moderately short lower jaw with quadrate-mandibular articulation below the anterior half of the orbit, caudal vertebrae with neural and haemal arches fused to their respective vertebral centrum, and parapophyses fused to their respective centrum. A phylogenetic analysis based on 198 characters and 43 taxa is performed. Following the phylogenetic hypothesis, the sister-group relationship Ascalaboidae plus more advanced teleosts stands above the node of Leptolepis coryphaenoides. Both nodes have strong support among teleosts. The results confirm the inclusion of Ascalabos, Ebertichthys and Tharsis as members of this extinct family. Tharsis elleri n. sp. (LSID urn:lsid:zoobank.org:act:6434E6F5-2DDD-48CF-A2B1-827495FE46E6, date: 13 December 2018) is so far restricted to one Upper Jurassic German locality – Wegscheid Quarry near Schernfeld, Eichstätt – whereas Tharsis dubius is known not only from Wegscheid Quarry, but also from different localities in the Upper Jurassic of Bavaria, Germany, and Cerin in France.

scholarly journals Decomposition of dinosaurian remains inferred by invertebrate traces on vertebrate bone reveal new insights into Late Jurassic ecology, decay, and climate in western Colorado

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9510
Author(s):  
Julia B. McHugh ◽  
Stephanie K. Drumheller ◽  
Anja Riedel ◽  
Miriam Kane
Keyword(s):  
Late Jurassic ◽  
Upper Jurassic ◽  
Site Formation ◽  
Morrison Formation ◽  
Bone Surface ◽  
The North ◽  
Western Colorado ◽  
Burial Rates ◽  
Minimum Residence Time ◽  
Taphonomic Analysis

A survey of 2,368 vertebrate fossils from the Upper Jurassic Mygatt-Moore Quarry (MMQ) (Morrison Formation, Brushy Basin Member) in western Colorado revealed 2,161 bone surface modifications on 884 specimens. This is the largest, site-wide bone surface modification survey of any Jurassic locality. Traces made by invertebrate actors were common in the assemblage, second in observed frequency after vertebrate bite marks. Invertebrate traces are found on 16.174% of the total surveyed material and comprise 20.148% of all identified traces. Six distinct invertebrate trace types were identified, including pits and furrows, rosettes, two types of bioglyph scrapes, bore holes and chambers. A minimum of four trace makers are indicated by the types, sizes and morphologies of the traces. Potential trace makers are inferred to be dermestid or clerid beetles, gastropods, an unknown necrophagous insect, and an unknown osteophagus insect. Of these, only gastropods are preserved at the site as body fossils. The remaining potential trace makers are part of the hidden paleodiversity from the North American Late Jurassic Period, revealed only through this ichnologic and taphonomic analysis. Site taphonomy suggests variable, but generally slow burial rates that range from months up to 6 years, while invertebrate traces on exposed elements indicate a minimum residence time of five months for carcasses with even few preserved invertebrate traces. These traces provide insight into the paleoecology, paleoclimate, and site formation of the MMQ, especially with regards to residence times of the skeletal remains on the paleolandscape. Comprehensive taphonomic studies, like this survey, are useful in exploring patterns of paleoecology and site formation, but they are also rare in Mesozoic assemblages. Additional work is required to determine if 16.174% is typical of bulk-collected fossils from Jurassic ecosystems in North America, or if the MMQ represents an unusual locality.

scholarly journals Upper Jurassic carbonate buildups in the Miechów Trough, Southern Poland – insights from seismic data interpretation

2019 ◽  
Author(s):  
Łukasz Słonka ◽  
Piotr Krzywiec
Keyword(s):  
Transition Zone ◽  
Seismic Data ◽  
Late Jurassic ◽  
Data Interpretation ◽  
Upper Jurassic ◽  
Carbonate Sediments ◽  
Northern Margin ◽  
Depositional System ◽  
Carbonate Buildups ◽  
Shelf Sedimentation

Abstract. The geometry and internal architecture of the Upper Jurassic carbonate depositional system in the epicontinental basin of western and central Europe, and within the northern margin of the Tethyan shelf are hitherto only partly recognised, especially in areas with thick Cretaceous and younger cover such as the Miechów Trough. In such areas, seismic data are indispensable for analysis of a carbonate depositional system, in particular for identification of the carbonate buildups and the enveloping strata. The study area is located in the central part of the Miechów Trough that in the Late Jurassic was situated within the transition zone between the Polish part of western and central European epicontinental basin and the Tethys Ocean. This paper presents the results of interpretation of 2D seismic data calibrated by deep wells that document the presence of large Upper Jurassic carbonate buildups. The lateral extent of particular structures is in the range of 400–1000 m, and their heights are in range of 150–250 m. Interpretation of seismic data revealed that the depositional architecture of the subsurface Upper Jurassic succession in the Miechów Trough is characterised by the presence of large carbonate buildups surrounded by basinal (bedded) limestone-marly deposits. These observations are compatible with depositional characteristics of well-recognised Upper Jurassic carbonate sediments that crop out in the adjacent Kraków-Częstochowa Upland. The presented study provides new information about carbonate open shelf sedimentation within the transition zone in the Late Jurassic, which proves the existence of much more extensive system of organic buildups which flourished in this part of the basin. Obtained results, due to high quality of available seismic data, provide also an excellent generic reference point for seismic studies of carbonate buildups from other basins and of different ages.

A new primitive eucryptodiran turtle from the Upper Jurassic Phu Kradung Formation of the Khorat Plateau, NE Thailand

2014 ◽  
Vol 152 (1) ◽  
pp. 166-175 ◽  
Author(s):  
HAIYAN TONG ◽  
WILAILUCK NAKSRI ◽  
ERIC BUFFETAUT ◽  
VARAVUDH SUTEETHORN ◽  
SURAVECH SUTEETHORN ◽  
...  
Keyword(s):  
New Species ◽  
Sichuan Basin ◽  
Late Jurassic ◽  
New Genus ◽  
Upper Jurassic ◽  
New Taxon ◽  
Full Width ◽  
The Sichuan Basin

AbstractA new genus and new species of primitive eucryptodiran turtle, Phunoichelys thirakhupti gen. et sp. nov., is described on the basis of shell remains from the lower part of the Phu Kradung Formation, at Phu Noi locality, Kalasin Province, NE Thailand. It is assigned to Xinjiangchelyidae on the basis of the marginals covering the lateral end of the costals and the anal scutes invading the hypoplastra. The new taxon is further characterized by a low and rounded carapace without a cervical notch; the whole carapace and plastron covered with a clear ornamentation consisting of tiny irregular vermiculated furrows; a complete neural series that reaches the suprapygal; a very wide and short cervical scute; relatively wide vertebral scutes; and a long first thoracic rib that extends along the full width of the first costal. The sutured plastron/carapace connection and the marginals covering the lateral end of the second to seventh costals suggest that the turtles from Phu Noi may be related to some primitive xinjiangchelyids from the Sichuan Basin. The discovery of a xinjiangchelyid turtle in the lower part of the Phu Kradung Formation supports a Late Jurassic age for that part of the formation.

The systematic position of the Late Jurassic alleged dinosaur Macelognathus (Crocodylomorpha: Sphenosuchia)

2005 ◽  
Vol 42 (3) ◽  
pp. 307-321 ◽  
Author(s):  
Ursula B Göhlich ◽  
Luis M Chiappe ◽  
James M Clark ◽  
Hans-Dieter Sues
Keyword(s):  
Late Jurassic ◽  
Upper Jurassic ◽  
Systematic Position ◽  
Lower Jurassic ◽  
Late Triassic ◽  
Morrison Formation ◽  
Postcranial Skeleton ◽  
Western Colorado ◽  
New Material ◽  
Limb Posture

Macelognathus vagans was described by O.C. Marsh in 1884, based on a mandibular symphysis from the Upper Jurassic Morrison Formation of Wyoming. Often considered a dinosaur but later tentatively referred to the Crocodylia, its phylogenetic identity has until now been enigmatic. New material of this species from the Morrison Formation of western Colorado demonstrates its affinities with basal crocodylomorphs commonly grouped together as the Sphenosuchia, which are characterized by a gracile postcranial skeleton with erect limb posture. Macelognathus shares features with Kayentasuchus from the Lower Jurassic Kayenta Formation of Arizona and Hallopus, which may be from the Morrison Formation of eastern Colorado. The new material constitutes the youngest definitive occurrence of a sphenosuchian, previously known from the Late Triassic to the Middle or Late? Jurassic.

THE REGIONAL GEOLOGY OF THE BONAPARTE GULF TIMOR SEA AREA

1974 ◽  
Vol 14 (1) ◽  
pp. 77 ◽  
Author(s):  
Robert A. Laws ◽  
Gregory P. Kraus
Keyword(s):  
Late Cretaceous ◽  
Late Jurassic ◽  
Oil And Gas ◽  
Upper Jurassic ◽  
Structural Configuration ◽  
Structural Pattern ◽  
Source Areas ◽  
Timor Sea ◽  
Early Palaeozoic ◽  
Sea Area

The present structural configuration of the Bonaparte Gulf-Timor Sea area is essentially the result of Mesozoic and Tertiary fragmentation of a once relatively simple Permo-Triassic Basin. A northwest-southeast Palaeozoic structural grain in the southeastern portion of the area resulted from early Palaeozoic faulting, possibly tied to aborted rift development. This faulting effectively controlled sedimentation throughout the Phanerozoic. Pronounced northeast-southwest Jurassic to Tertiary structural trends dominate the central and northern area, paralleling the present edge of the continental shelf and swinging south southwest into the northern extension of the Browse Basin. Post-Palaeozoic epeirogenies which had the greatest effect on the regional structural pattern occurred in the mid-Jurassic, Early Cretaceous, within the Eocene and in the Plio-Pleistocene.The Kimberley and Sturt Blocks flanking the basin to the south and east constituted the most important source areas for clastic sedimentation throughout the Phanerozoic. Periodic contributions during the Mesozoic were derived from a postulated source to the northwest in the vicinity of the present-day Timor Trough.The maximum thickness of Phanerozoic sediments present within the Bonaparte Gulf-Timor Sea area exceeds 50,000 ft (15,000 m). Early Palaeozoic to Carboniferous evaporites, carbonates and clastics are unconformably overlain by a thick sequence of Permian deltaic sediments in the southeastern Bonaparte Gulf Basin. This is succeeded by a Triassic to Middle Jurassic transgressive-regressive clastic sequence, grading northwestward to marginal marine and marine clastics and carbonates. The Permian to mid-Jurassic sediments are unconformably overlain by Upper Jurassic sands and shales, mainly fluvial in the southeast and north, becoming more marine westward. These clastics are everywhere succeeded by a monotonous sequence of Cretaceous shales and shaly limestones followed by a generally north to northwesterly thickening wedge of Tertiary carbonates and minor elastics.Hydrocarbon shows have been noted offshore in rocks of Carboniferous, Permian, Late Jurassic, Late Cretaceous and Eocene age. Porous clastics in conjunction with thick and laterally-extensive, organically-rich shales are present within the Palaeozoic and Mesozoic sequences. These sediments, in association with fault- and diapir-related anomalies and stratigraphic plays, combine to make certain provinces of the Bonaparte Gulf-Timor Sea area prospective in the search for viable oil and gas reserves.

Dinoflagellate cysts from an allochthonous block of Nordenskjöld Formation (Upper Jurassic), north-west James Ross Island

1992 ◽  
Vol 4 (3) ◽  
pp. 267-278 ◽  
Author(s):  
Michael G. Snape
Keyword(s):  
New Species ◽  
Papua New Guinea ◽  
Antarctic Peninsula ◽  
Late Jurassic ◽  
New Genus ◽  
Upper Jurassic ◽  
Dinoflagellate Cysts ◽  
Dinoflagellate Cyst ◽  
North West ◽  
James Ross Island

An allochthonous block of the Nordenskjöld Formation from north-west James Ross Island, Antarctic Peninsula has yielded a diverse marine palynoflora. Dinoflagellate cyst assemblages from the 185 m thick sequence are described and compared with similar microfloras previously described from Australia, Papua New Guinea and Madagascar. A mid Tithonian (Late Jurassic) age is suggested for the section. One new genus, Helbydinium gen. nov. and four new species, Helbydinium scabratum sp. nov., Leptodinium acneum sp. nov., Leptodinium posterosulcatum sp. nov. and Rhynchodiniopsis foveata sp. nov. are described.

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