Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "upper Elliot Formation" wg kryterium: Temat


Wyświetlanie 1-2 z 2
Tytuł:
Large tridactyl dinosaur tracks from the Early Jurassic of southern Gondwana : uppermost Elliot Formation, Upper Moyeni, Lesotho
Autorzy:
Abrahams, Miengah
Sciscio, Lara
Reid, Mhairi
Haupt, T’nielle
Bordy, Emese M.
Powiązania:
https://bibliotekanauki.pl/articles/1836362.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
vertebrate ichnology
tridactyl
large theropods
southern Gondwana
Karoo
upper Elliot Formation
Opis:
A new ichnosite in southwest Lesotho (Upper Moyeni; Quthing District) is located within the uppermost part of the highly fossiliferous Elliot Formation, ~35 m below the conformably overlying Clarens Formation and ~65 m above the world-renowned Lower Moyeni ichnosite. While the Lower Moyeni site preserves diverse Early Jurassic ichnofossils, the ichnites at the Upper Moyeni comprise one vertebrate burrow and ~50 tridactyl tracks with footprint lengths between 15 and 51 cm. Many of the tracks preserve digital pad impressions, claw marks and displacement rims, all related to substrate conditions. The morphometric parameters of the Upper Moyeni tracks are consistent with Grallator, Eubrontes and Kayentapus. Several larger tracks with footprint lengths > 40 cm are Kayentapus-like and Eubrontes-like, and are comparable to previously described very large theropods tracks with lengths > 50 cm from the uppermost Elliot and Clarens formations. On the basis of sedimentological and ichnological evidence, the Upper Moyeni ichnofossils were formed in a palaeolandscape with small rivers and shallow lakes by burrowing tetrapods and a variety of bipedal dinosaurs (theropods), some of which were up to 7–8 m in body length. The Upper Moyeni tracks, together with the other very large tracks from coeval locations in southern Africa, collectively highlight the tendency towards increasing diversity in size of tridactyl tracks and by extension theropod trackmaker body size body size, which runs in tandem with the increasing diversity of non-sauropod, sauropodomorph body fossils in the Sinemurian-Pliensbachian of southern Gondwana.
Źródło:
Annales Societatis Geologorum Poloniae; 2020, 90, 1; 1-26
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dinosaur behaviour in an Early Jurassic palaeoecosystem – uppermost Elliot Formation, Ha Nohana, Lesotho
Autorzy:
Rampersadh, A.
Bordy, E. M.
Sciscio, L.
Abrahams, M.
Powiązania:
https://bibliotekanauki.pl/articles/191599.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
vertebrate ichnology
tridactyl
tetradactyl
climate change
southern Gondwana
Karoo
upper
Elliot Formation
Opis:
The Ha Nohana palaeosurface in southern Lesotho preserves tridactyl and tetradactyl tracks and trackways attributable to Early Jurassic bipedal, theropod-like dinosaurs. Complementary sedimentological and ichnological observations along the palaeosurface and in the strata below and above it allow detailed interpretations of climatically driven changes in this southern Gondwana palaeoecosystem. Sedimentological evidence suggests trackmaking under a semi-arid climate with heavy storms and episodic flash flooding that induced ephemeral, unconfined sheetwashes. The palaeosurface is overlain by rhythmically bedded, organic-matter rich mudstones that formed in a deep, stratified lake indicative of a longer and wetter period in the history of the site. The unique morphological details of the Ha Nohana tracks help refine the properties of the substrate during track making, the ichnotaxonomic affinities of the footprints and the interpretation of the foot movement relative to the substrate. Two footprint morphotypes, ~ 300 m apart, are defined on the palaeosurface. Tracks of morphotype I are tridactyl, shallow, contain digital pad impressions and were impressed on a firm, sand rippled substrate that underwent desiccation. Conversely, tracks of morphotype II are tetradactyl, deep, and have an elongated posterior region. These tracks are preserved on the surface of a massive sandstone and are associated with soft sediment collapse structures related to the animal’s foot sinking into the water-saturated, malleable sediment layer. Morphotype II tracks show that as the animal waded across the substrate, the liquefied sediment lost its cohesive strength and could only partially support the weight of the animal. In so doing, the animal’s foot sunk deep enough into the sediment such that the impression of the metatarsal and digit I (hallux) are now visible. Thus, the palaeosurface was walked on by small-to-medium sized theropods that traversed over ripple marks in firmer moist sand, as well as a larger theropod that tottered through water-logged sand.
Źródło:
Annales Societatis Geologorum Poloniae; 2018, 88, 2; 163-179
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies