Did you know?

Background Extended neoteny and late stage allometric growth increase morphological disparity between growth stages in at least some dinosaurs. Coupled with relatively low dinosaur density in the Upper Cretaceous of North America, ontogenetic transformational representatives are often difficult to distinguish. For example, many hadrosaurids previously reported to represent relatively small ...The Upper Cretaceous Israeli marine succession was influenced by two major unrelated processes: (1) Tectonic-control of the Syrian Arc fold system that differentiated the outer-shelf into ...Tröger K-A (1989) Problems of Upper Cretaceous inoceramid biostratigraphy and paleobiogeography in Europe and western Asia. In: Wiedmann J (ed) Cretaceous of the Western Tethys. Proceedings of the 3rd International Cretaceous Symposium Tübingen 1987. Schweizerbart, Stuttgart. Google Scholar Wani R, Gupta NS (2015) Ammonoid …The recently described Dineobellator notohesperus, consisting of a partial skeleton from the Upper Cretaceous (Maastrichtian) of New Mexico, is the only diagnostic dromaeosaurid to be recovered ...Sep 1, 2021 · These successions correspond to four distinct tectono-sedimentary phases, from older to younger forming the Upper Paleozoic Karoo Supergroup, the Cretaceous Galula Formation, the Oligocene Nsungwe Formation and the Miocene-Recent Lake Beds strata (Roberts et al., 2012) (Fig. 1). The hard skeletons of belemnites (the guard or. rostrum) are common in the Upper Cretaceous. chalks and marls of Boreal Europe, and it is here. phylogeny of the belemnites has been worked. out ...Japanese Upper Cretaceous marine reptile fossils occur in five major stratigraphical units: the Yezo, Kuji, Futaba, Izumi, and Goshoura groups (Figs. 1 and 2; Table 1).Many of these specimens were excavated by private collectors and donated to local museums; therefore, their locality data is based solely on museum records and/or published accounts.The fossil remains of young dinosaurs are very rare. This juvenile hadrosaur is a cast of one of the fifteen individuals of baby Maiasaura ("good mother lizard") collected in 1978 by Princeton University from the Upper Cretaceous (80-65 million years ago) Two Medicine Formation of Teton County in western Montana. The presence of several small …Our porosity evaluation focuses on the Upper Cretaceous and Tertiary interval that overlies the Eagle Ford Formation in South Texas (Fig. 1).This 3-4 km thick, shale-dominated section was a passive margin during deposition and, other than some localized normal faulting, there is little structural deformation and no significant unconformities (i.e., gaps in geologic time) in the interval of ...The Austin Group (Coniacian-Santonian) is a sequence of interstratified chalk and marl deposited during a sea-level highstand as a transgressive unit. Austin Chalk deposition occurred on a southeastward-dipping carbonate ramp that exhibits distinctive onshore and offshore chalk lithofacies. Discrete intervals within offshore Austin lithofacies ...Tectonism during the early Cretaceous in western North America resulted in the development of a foreland basin and formation of the Western Interior Seaway (e.g. Burchfiel et al., 1992). By Maastrichtian times, this epeiric sea linked the polar ocean and the subtropical Gulf of Mexico . The Upper Cretaceous succession currently exposed in the ...The Upper Cretaceous chalks of southern England are a thick sequence of rhythmically bedded, bioturbated coccolith micrites, deposited in an outer shelf environment in water depths which varied between 50 and 200-300 m. The products of sea floor cementation are widely represented in the sequence, and a series of stages of progressive ...Upper Cretaceous pelagic red carbonates which consist of limestone and muddy limestone within the Eastern Pontides, NE Turkey (Fig. 1). There, the red beds have a great lateral extent with remarkable lithology and thickness of up to 45 m, and are characterized by abun-Judith River near the confluence with the Missouri River. Named by. F.V. Hayden, 1871; [2] F.B. Meek, 1876. [3] The Judith River Formation is a fossil -bearing geologic formation in Montana, and is part of the Judith River Group. It dates to the Late Cretaceous, between 79 and 75.3 million years ago, [4] corresponding to the "Judithian" land ...The Cretaceous climate was characterized by arid and semiarid conditions in different parts of the world. Climatic changes for the Early to Late Cretaceous had been reported by many authors in North America, East Asia, Africa, and South America due to the geological evolution of Laurasia and Gondwana.In South America, the Bauru Basin, located in Brazil, is one of the most critical places to ...The irregular spatial distribution is explained by the fact that in the most of the West Siberian sedimentary basin the Cretaceous is overlapped by Cenozoic sediments (e.g. Kontorovich et al., 2014). Upper Cretaceous outcrops are only available at the flanks of the basin, and in the Yenisei–Khatanga trough in the east.The Santo Anastácio Formation (Lower Cretaceous - Albian) is constituted by reddish-yellow massive/rooted paleosols generated over aeolian sandstones (draa facies association according Batezelli, 2015).The Araçatuba Formation (Upper Cretaceous - Campanian) is constituted by greenish to red very fine-grained silty sandstones and sandy siltites, with normal gradation, and planar-parallel ...Hunt, C.O. 1987. Dinoflagellate cyst and acritarch assemblages in shallow-marine and marginal-marine carbonates: the Portland Sand, Portland Stone, and Purbeck Formations (Upper Jurassic/Lower Cretaceous) of southern England and northern France. In: Hart, M.B. (ed) Micropalaeontology of Carbonate Environments.Section snippets Materials and experiments. Twenty-one lacustrine shale core samples were obtained from the Upper Cretaceous Qingshankou Formation (K 2 qn) of Songliao Basin, NE China. The Songliao Basin is a Mesozoic-Cenozoic basin with an area of about 260,000 km 2 (Fig. 1). The Qingshankou Formation of Songliao Basin consists of lacustrine mudstone and shale up to 550 m thick that ...The Wind River Basin of central Wyoming trends west-northwest from near the community of Alcova to near the town of Dubois (fig. 1). On the perimeter of the basin, outcrops of the Frontier Formation were examined and described during the years 1972-1975. Invertebrate fossils were collected from those outcrops during the years 1972-1996, in places with the assistance of other earth scientists ...A carbonate hardground surface with a bryozoan and vertiODP Leg 132, with some Upper Cretaceous sediment recov The Hell Creek Formation is an intensively studied geological formation of mostly Upper Cretaceous and some Early Paleocene rocks in North America, named for exposures studied along Hell Creek, near Jordan, Montana. The formation stretches over portions of Montana, North Dakota, South Dakota, and Wyoming. In Montana, the Hell Creek Formation ...The Dinosaur Park Formation is the uppermost member of the Belly River Group (also known as the Judith River Group), a major geologic unit in southern Alberta.It was deposited during the Campanian stage of the Late Cretaceous, between about 76.5 and 74.4 million years ago. It was deposited in alluvial and coastal plain environments, and it is bounded … The Cretaceous period was the last and longest segment of the M Paleoenvironmental changes recorded in the Santa Marta Formation (Santonian—Campanian, Upper Cretaceous), James Ross Island, Antarctica, inferred from palynofacies analyses. Gustavo Santiago, Marcelo de Araujo Carvalho, Renato Rodriguez Cabral Ramos, Sandro Marcelo Scheffler. In Press, Journal Pre-proof, Available online 28 September 2023.Apatite U–Pb dating of dinosaur teeth from the Upper Cretaceous Nemegt Formation in the Gobi Desert, Mongolia: Contribution to depositional age constraints Sep 4, 2023 · The first fossils of short-tail

Upper Cretaceous-Paleocene Magnetostratigraphy of the Longmenshan Foreland Basin and Its Implications for the Tectonic Deformation of the Longmenshan Fault Zone. ... The LMSFZ experienced two stages of uplift during the Cretaceous-Early Cenozoic (at 128.0-124.1 and 68.8-64.1 Ma). (b) The stress field generated by the subduction and ...Govindan A (1972) Upper Cretaceous planktonic foraminifera from the Pondicherry area, South India. Micropaleontol 18:160–193. Google Scholar Govindan A (1993) Cretaceous anoxic events, sea level changes and microfauna in Cauvery Basin, India. In: Proceedings of second seminar on petroliferous basins of India, vol 1.The Cretaceous Period is considered the archetypical greenhouse interval, yet there is mounting evidence for intermittent cooler climatic phases throughout this geologic span. Few continental climate histories exist for the Cretaceous south of the paleoequator, and fewer still for Africa during this time. The Cretaceous Galula Formation is one of the few exposed fossiliferous continental ...The Saratoga Chalk of Arkansas yields a rich ammonite fauna of 17 species, referred to the Nostoceras (N.) hyatti zone. Recognition that the northwest European N. (N.) pozaryskii Blaszkiewicz, 1980, is a synonym of N. (N.) hyatti Stephenson, 1941, and N. (N.) helicinum (Shumard, 1861) dates the zone as latest Campanian on the basis of co-occurrence with Belemnitella langei Jeletzky, 1948, in ...

A new megaraptoran theropod dinosaur from the Upper Cretaceous Bajo de la Carpa Formation of northwestern Patagonia. Cret. Res. …The Upper Cretaceous to Paleogene sequences in the Middle East are characterized by regional anoxic black shale occurrences, enriched in different stratigraphic levels of various local basins (Abed et al., 2005; Almogi-Labin et al. 1990a, 1993; Ashckenazi-Polivoda et al., 2010, 2011; Holbourn et al., 1999; Inan et al., 2010). The studied black ...The Upper Cretaceous (Turonian) Akrabou Formation at Asfla in south east Morocco is a marine carbonate succession well-known for its exceptionally preserved, often three-dimensional marine vertebrate fossils.It is perhaps best known for its diverse ichthyological assemblage comprising both cartilaginous and bony fishes, notably ……

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs. The Lower Cretaceous is the first geological epoch in the Cre. Possible cause: Background Dinosaur eggs containing embryos are rare, limiting our understanding of .