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Hettangian tetrapod burrows from the continental Steierdorf Formation at Anina, western Romania

Csiki-Sava Z., Kedzior A., Pienkowski G., Popa M. E.

Geological Quarterly

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2016

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Vol. 60, No. 2

395--406

EN

Very large, sparsely distributed, sinuous, gently dipping and occasionally branching tunnels with subordinate swells, as well as possible chambers and scratches, are described from the Hettangian Dealul Budinic Member of the Lower Jurassic continental Steierdorf Formation at Anina in the South Carpathians, Romania, and are interpreted as tetrapod burrows. No bone remains have been found in association with these structures. The morphology and large dimensions of the burrows suggest that the trace-makers were sauropsid amniotes, most probably either crocodyliforms or small-sized basal neornithischian dinosaurs, although their therapsid affinities, despite being less likely, cannot be discarded either. The age, large size and probable origin of these burrows add important information to a poorly documented period of the evolution of tetrapod fossoriality. It may be suggested that within a relatively short time interval following the Triassic-Jurassic extinction event, when environmental conditions were still marked by strongly seasonal climate with prolonged droughts as well as extreme moisture and temperature fluctuations, fossorial habit probably became yet again an endurance strategy for burrow makers.

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New data on small theropod dinosaurs from the Upper Jurassic Morrison Formation of Como Bluff, Wyoming, USA

Dalman S.

Volumina Jurassica

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2014

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Vol. 12, no. 2

181--196

EN

In 1879, Othniel C. Marsh and Arthur Lakes collected in the Upper Jurassic Morrison Formation Quarry 12 at Como Bluff, Wyoming, USA, several isolated axial and appendicular skeletal elements of small theropod dinosaurs. Since the discovery the specimens remained unnoticed for over a century. The skeletal remains of small theropods are rare at Como Bluff and throughout the Morrison Formation. Their bones are delicately constructed, so they are not as well-preserved as the bones of large-bodied theropods. The bones of small theropods described here were found mixed with isolated crocodile teeth and turtle shells. Comparison of the skeletal materials with other known theropods from the Morrison Formation reveals that some of the bones belong to a very small juvenile Allosaurus fragilis and Torvosaurus tanneri and also to a new ceratosaur taxon, here named Fosterovenator churei, whereas the other bones represent previously unidentified juvenile taxa of basal tetanuran and coelurid theropods. The discovery and description of these fossil materials is significant because they provide important information about the Upper Jurassic terrestrial fauna of Quarry 12, Como Bluff, Wyoming. The presence of previously unidentified theropod taxa in the Morrison Formation indicates that the diversity of basal tetanuran and coelurid theropods may have been much greater than previously expected. Although the fossil material here described is largely fragmentary, it is tenable that theropods of different clades co-existed in the same ecosystems at the same time and most likely competed for the same food sources.

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Jurassic tetrapod footprint ichnofaunas and ichnofacies of the Western Interior, USA

Lockley M., Gierlinski G.

Volumina Jurassica

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2014

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Vol. 12, no. 2

133-150

EN

The Jurassic tetrapod track record of the Western Interior, USA, is one of the most diverse, complete and well-studied in the world, spanning a relatively continuous representation of Lower, Middle and Upper Jurassic formations. Although a few of these formations, notably the Morrison Formation, have yielded abundant body fossils, the majority lack abundant skeletal remains and, while trackrich, are in some cases completely barren of body fossils. Thus, the track record assumes great importance as the most complete and representative record of changing tetrapod faunas through time in a region where the body fossil record is often sparse or absent. In the Lower and Middle Jurassic, many distinctive assemblages are associated with eolian units (Wingate, Navajo and Entrada) that are almost devoid of body fossils. However, the former two units are rich in synapsid tracks characterized as the Brasilichnium ichnofacies. In the Middle Jurassic, fluctuating sea-levels exerted important controls on the distribution of theropod and pterosaur-dominated ichnofaunas associated with coastal plain and marginal marine settings. The Morrison ichnofauna is a reliable reflection of the body fossil record of that formation. Ongoing efforts to group and classify the various tetrapod ichnofaunas into tetrapod ichnofacies and tetrapod biochron categories have, in some cases, provoked stimulating, if sometimes inconclusive, debate.

4

A U/Pb age for the Mygatt-Moore Quarry, Upper Jurassic Morrison Formation, Mesa County, Colorado

Trujillo K., Foster J., Hunt-Foster R., Chamberlain K.

Volumina Jurassica

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2014

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Vol. 12, no. 2

107--114

EN

Mygatt-Moore Quarry in the Brushy Basin Member of the Upper Jurassic Morrison Formation is one of the more important large dinosaur quarries in the formation, yielding fossils of sauropod dinosaurs including Apatosaurus, Camarasaurus, and an indeterminate diplodocine (cf. Diplodocus or Barosaurus), the theropod dinosaurs Allosaurus and Ceratosaurus, and the ornithischians Othnielosaurus and Mymoorapelta. Fossil wood and carbonized plants are known from the deposit, and carbonized dinosaur skin has also been discovered. We report here on a new U/Pb radiometric age for the Mygatt-Moore Quarry, from a smectitic mudstone collected at the quarry horizon. We isolated zircons using an ultrasonic separation technique and standard heavy liquid and magnetic methods, analyzed single zircons using a chemical abrasion method (CA-TIMS). The age determined for this dinosaur quarry, 152.18 ±0.29 Ma, places the quarry at the boundary between the Kimmeridgian and Tithonian stages of the Late Jurassic Period. This age can now be used to place the quarry into stratigraphic position with respect to other dated horizons in the Morrison Formation and other rock units worldwide. We will also use this age along with other ages to create a radiometrically based stratigraphic framework for the Morrison Formation.

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Dinosaur assemblages from the Middle Jurassic Shaximiao Formation and Chuanjie Formation in the Sichuan-Yunnan Basin, China

Li K., Yang Ch., Hu F.

Volumina Jurassica

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2011

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Vol. 9, no. 1

21-42

EN

The Shaximiao Formation (Sichuan Basin, China), and the corresponding Chuanjie Formation of the neighboring Yunnan Basin (Sichuan-Yunnan Basin), representing continental Mesozoic strata, are distinguished from other Chinese Mesozoic units because of the large area over which they are distributed, their lithological characteristics and their abundant vertebrate fossils. This paper analyses and summarizes the dinosaur fossils from the Shaximiao Formation and compares them to other vertebrate groups of the same or similar ages, both in China and abroad. For the first time, this paper presents the viewpoint that the upper member of the Shaximiao Formation is of Middle Jurassic age (Bathonian–Callovian). Furthermore, we claim that the entire Shaximiao Formation is of Bajocian–Callovian age (middle-late part of Middle Jurassic). This conclusion is supported by the age inferred from invertebrate fossils and radiometric dating (165–178 Ma). The composition, evolution and geological age of the vertebrate fauna (particularly dinosaur fossils), as well as their comparison to the dinosaur fauna from the other parts of the Sichuan-Yunnan Basin (Chuanjie Fm.) is discussed. Middle Jurassic dinosaur assemblages from China show marked differences compared with other dinosaur assemblages in the world, and this is explained by geographical isolation.

6

Differences in global biomass and energy use between dinosaurs and mammals

Trammer J.

Acta Geologica Polonica

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2011

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Vol. 61, no. 2

125-132

EN

Estimates derived from the literature suggest that dinosaurs, even if they had a mammalian-type metabolism, produced globally much more biomass than mammals for the same amount of energy consumed. The average body mass of an individual dinosaur was several thousand times greater than in the case of mammals. Dinosaurs were one to several hundred times less numerous than mammals and, in comparison to mammals, the average number of individuals per dinosaur species was several to a dozen or so times lower than in mammals.

7

Krajobraz kulturowy wsi Krasiejów ze specyficzną funkcją ekspozycji dinozaurów

Szachowicz U., Niedźwiecka-Filipiak I.

Prace Komisji Krajobrazu Kulturowego

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2008

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nr 10

248--255

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Palaeoenvironmental interpretation of dinosaur- and mammal-bearing continental Maastrichtian deposits, Hateg basin, Romania

Bojar A. V., Grigorescu D., Ottner F., Csiki Z.

Geological Quarterly

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2005

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Vol. 49, No. 2

205--222

EN

The Hateg basin, South Carpathians, Romania, contains a thick sequence of Maastrichtian continental deposits from which a rich dinosaur and mammal fauna is known. Field data as well as mineralogical and stable isotope analyses from three representative profiles were integrated in order to reconstruct environmental conditions during Maastrichtian time. Tustea quarry is characterized by the presence of well drained calcisols, with smectite (montmorillonite) as the main clay component. Along the profile, the δ18 O and δ13 C isotopic compositions of calcretes show a small variation, of up to 0.9‰. The profile along the Barbat Valley shows preponderantly calcisols, the main clay mineral being smectite, with subordinate illite and chlorite. The oxygen isotopic compositions of calcretes are ~0.5‰ lighter than those from Tustea. The soils are interpreted as having formed under more humid conditions and they are similar to those situated at the bottom of the sequence developed along Sibisel Valley. The abundant smectite from the Tustea and Barbat Valley depos its, as well the presence of good developed soils, reflects palaeoenvironmental conditions predominantly controlled by climate. Preliminary magnetostratigraphic data along the Sibisel Valley section indicate that sedimentation started at the end of chron C32n. All other palaeomagnetic sites distributed up stream, as far as the upper limit of this formation, have only reversed polarity and the corresponding time interval is probably chron C31r. Along this valley, the sequence shows a general coarsening upward trend. The palaeosol type changes from calcisol- to vertisol-dominated sequences. The soils are moderate to weakly developed. The mineralogical composition of the clay fraction also changes, from smectite- to illite and chlorite-dominated. These features points to wards unstable tectonic conditions and higher uplift rates of the surrounding area within chron C31r. To wards the top of the sequence, the oxygen and carbon isotopic composition of calcretes be come 1 and ~2‰ lighter, respectively. These changes indicate a transition from generally semi-arid to wards more humid and possible cooler conditions and correlate with the world wide trend for chron 31r.

9

Nowe znaleziska tropów dinozaurów ze śladem śródstopia z dolnej jury Gór Świętokrzyskich

Niedźwiedzki G., Niedźwiedzki D.

Przegląd Geologiczny

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2004

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Vol. 52, nr 3

237-242

EN

Numerous specimens of dinosaur footprints with metatarsal impressions were collected from the Early Jurassic deposits of the Holy Cross Mountains, Poland. These elongate theropod and ornithischian footprints came from the Hettangian sites of Sołtyków, Gromadzice, and Gliniany Las. The following dinosaur ichnogenera were identified among them: Anchisauripus Lull, 1904; Kayentapus Welles, 1971; Moyenisauropus Ellenberger, 1974; Anomoepus Hitchcock, 1848.

10

Tropy dinozaurów ze śladem śródstopia z wczesnojurajskich osadów Polski

Niedźwiedzki G., Niedźwiedzki D.

Przegląd Geologiczny

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2001

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Vol. 49 nr 7

649-650

PL

Podczas prac badawczych prowadzonych w latach 1997-1999 na północnym obrzeżeniu Gór Świętokrzyskich autorzy znaleźli tropy dinozaurów ze śladem śródstopia. Nowe odkrycia składają się z tropów dinozaurów ptasiomiednicznych z ichnorodzaju Moyenisauropus i Anomoepus oraz tropów teropodów z ichnorodzaju Kayentapus i Anchisauripus. Materiał omówiony w pracy został zebrany w odkrywkach hetangu w Sołtykowie, Gromadzicach i Glinianym Lesie.

EN

During the fieldwork in 1997-1999 in the northern margin of the Holy Cross Mountains, the present authors found dinosaur tracks with metatarsal impressions. The recently discovered tracks are assigned to ornithischians of the ichnogenus Movenisauropus and Anomoepus, and theropods of Kayentapus and Anchisauripus. The material described was collected from Hettangian deposits ofSollvkow, Gromadzice. and Gliniany Las.

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New ornithischian dinosaur footprints in the Jurassic of Poland

Gierliński G., Gaździcka E., Niedźwiedzki G., Pieńkowski G.

Geological Quarterly

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2001

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Vol. 45, No 2

205-210

EN

New stratigraphic horizons with the ornithischian footprints have been found in central Poland. Basal thyreophoran ichnites are reported from the middle Hettangian Skloby Formation of Gromadzice. They support the previous conclusion that small and medium-sized Early Jurassic ornithischians preferred a coastal habitat with low-rise vegetation. Another find, an ornithopod footprint, came from the early Kimmeridgian Glowaczow Formation of Ożarow quarry. The track was discovered within the shallow-marine succession of calcareous deposits, which contributes to the interpretation of synsedimentary emersion of that area during the early Kimmeridgian.