scholarly journals Discovery of the Early Cretaceous Ankylosaur Gastroliths and Scale Impressions from the Ordos Basin, Inner Mongolia, China

2016 ◽  
Vol 06 (05) ◽  
pp. 355-360 ◽  
Author(s):  
书安 姬
1993 ◽  
Vol 30 (10) ◽  
pp. 2128-2138 ◽  
Author(s):  
Donald B. Brinkman ◽  
Jiang-Hua Peng

Ordosemys leios, n.gen., n.sp., from the Early Cretaceous Luohandong Formation, Zhidan Group, Ordos Basin, Inner Mongolia, is a primitive aquatic turtle with a reduced, fenestrated plastron. It shares with the members of the Centrocryptodira the presence of well-formed articular surfaces on the cervical and caudal vertebrae. Within the Centrocryptodira, characters of the cervical vertebrae suggest it is more closely related to the Polycryptodira than is the Meiolaniidae. Ordosemys shares with the Chelydridae the presence of two procoelous anterior caudals, but this character may be primitive for the Polycryptodira. Characters of the basicranial region of the braincase shared by Ordosemys and the Chelonioidea support a sister-group relationship between these two taxa, but a sister-group relationship between Ordosemys and the Polycryptodira is more strongly supported by characters shared by the Chelonioidea and other members of the Polycryptodira.


1993 ◽  
Vol 30 (10) ◽  
pp. 2163-2173 ◽  
Author(s):  
Dale A. Russell ◽  
Zhi-Ming Dong

An articulated skeleton of a 1 m long theropod from Early Cretaceous strata in Inner Mongolia is clearly referrable to the Troodontidae, representing the most complete specimen known of this group of small carnivorous dinosaurs. The tail and neck of the animal were curled next to its body upon burial; the upper surface of the skeleton was badly damaged by erosion. Previously unknown details of troodont morphology include a quadratic contact with the braincase wall (forming part of a channel leading to the lateral depression), a presacral vertebral count possibly similar to that of most theropods, absence of ossified caudal tendons, presence of a rod-like clavicle, and absence of sternal ossifications. A new genus and species (Sinornithoides youngi n.gen., n.sp.) is established for the specimen on the basis of its short skull, laterally directed orbital rim of the frontal, and elongated hind limb. A reassessment of character distributions in other small theropods and primitive birds must be completed before troodontid affinities can be established with greater precision.


1993 ◽  
Vol 30 (10) ◽  
pp. 2177-2179 ◽  
Author(s):  
Zhi-Ming Dong

The discovery of an Early Cretaceous bird from the Ordos Basin of Inner Mongolia (People's Republic of China) is reported. The specimen, collected by the Dinosaur Project (China – Canada – Alberta – Ex Terra) Expedition of 1990, includes scapulocoracoids, humeri, radii, ulnae and metacarpals. It is referred to the Enantiornithes.


1993 ◽  
Vol 30 (10) ◽  
pp. 2153-2162 ◽  
Author(s):  
Donald B. Brinkman ◽  
Zhi-Ming Dong

New material of Ikechosaurus sunailinae from the Early Cretaceous Laohongdong Formation of the Ordos Basin, Inner Mongolia, People's Republic of China, is described. This material, which includes well-preserved articulated skeletons and a series of isolated elements, demonstrates that Ikechosaurus is more closely related to Champsosaurus than to Simoedosaurus, sharing with Champsosaurus the presence of an elongate snout, anteriorly constricted parasphenoid with the foramen canalis caroticus internus located in or near the suture between the parasphenoid and the pterygoid, an anterior extension of the anterior end of the jugal, and an elongate symphysis including the splenial. Ikechosaurus is primitive relative to Champsosaurus in the anterior position of the internal narial openings, in the less strongly flared temporal region with the temporal openings placed largely above one another, in the absence of fenestra in the occiput between the parietal and squamosal, and in the interpterygoid vacuity bordered posteriorly by the basisphenoid. Ikechosaurus and Tchoiria are at a similar grade of evolution, but can be separated by details in the arrangement of bone forming the skull roof.


1993 ◽  
Vol 30 (10) ◽  
pp. 2139-2152 ◽  
Author(s):  
Donald B. Brinkman ◽  
Jiang-Hua Peng

Sinemys lens is redescribed on the basis of new material from the Early Cretaceous of Shandong, China, and a new species of Sinemys from the Ordos Basin in Inner Mongolia is recognized. Sinemys and Manchurochelys are placed in the Sinemydidae (sensu stricto) on the basis of the derived features of a small first suprapygal and an elongate, narrow posterior lobe of the plastron. Sinemys is autapomorphic in the absence of a cervical scute, the entry of the first vertebral onto the anterior margin of the carapace, the absence of a pygal bone, the entry of the fifth vertebral scute into the posterior margin of the carapace, in that the riblike lateral projections of the last three costal bones fit between the adjacent peripherals, and in the isolation of the epiplastra from the hyoplastra by lateral expansion of the entoplastron.Sinemys gamera sp.nov., from the Early Cretaceous Luohandong Formation of the Ordos Basin, Inner Mongolia, is characterized by the presence of a flat carapace with an abbreviated posterior end and the presence of long spines on the seventh costal. The spines in S. gamera may serve a hydrodynamic function.


Palaeoworld ◽  
2018 ◽  
Vol 27 (2) ◽  
pp. 188-201 ◽  
Author(s):  
Yun-Feng Li ◽  
Chun-Lin Sun ◽  
Hongshan Wang ◽  
David L. Dilcher ◽  
Xiao Tan ◽  
...  

2020 ◽  
Author(s):  
Dengfa He

<p>Craton is the stable unit of the lithosphere. The cratonic basin is thus the sedimentary basin developed upon craton. It has long been recognized as a kind of basin characterized by minor tectonic deformation and stable architecture. With the increasing evidences in the recent years, it is noticed that it has much more mobility, and is controlled not only by the lithospheric plate movements but also by the deep mantle activation. To explore the mobile behaviour of cratonic basin is an important window to address the intra-continental deformation mechanism. Taking the Ordos basin as an example, based on the new deep boreholes, the high-resolution seismic reflection profiles, cores, and the outcrops around the basin, the paper establishes the chronology of tectonic movement around the Ordos basin utilizing the integrated method of the isotopic dating, the bio-stratigraphy, and the sequence stratigraphy. It shows that, the basin developed the ten regional unconformities, underwent multi-period volcanic activities during the Middle Proterozoic, the late Early Paleozoic, the Late Triassic, and the Early Cretaceous. It was subjected to multi-stage compression, such as the Late Ordovician to Devonian, the Late Triassic, the Late Jurassic to Early Cretaceous, and the Neogene to Quaternary. Upon the crystalline basement of the Archaean and the Lower Proterozoic, the basin underwent five distinct extension-compression cycles, such as the extension in middle Proterozoic and compression in late Proterozoic, the extension in Cambrian to early Ordovician and compression in late Ordovician to Devonian, the extension in Carboniferous to middle Triassic and compression in late Triassic, the extension in early to middle Triassic and compression in late Jurassic to Cretaceous, and the extension in Paleogene and compression in Neogene to Quaternary, with a charter of a much longer period of the earlier cycle and a shorter period of the later cycle, and a longer period of extension and a shorter period of contraction in each cycle. The extension-compression cycle controlled the formation and evolution of the Ordos oil and gas super basin.</p>


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