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Multivariate analysis is used to differentiate shape variations between ichnites of theropod and ornithopod dinosaurs. Tracks of an alleged theropod cf. Tyrannosauropus from the mid-Cretaceous (late Albian-Cenomanian) Winton Formation of Lark Quarry, central-western Queensland, Australia were examined and foot shape ratios calculated. Multivariate analysis of these shape variables indicates this track-maker was an ornithopod dinosaur. A strong morphological similarity exists between the Lark Quarry ichnites and those of the iguanodontian ichnotaxon Amblydactylus gethingi. Considering the grade of ornithopod this ichnogenus is thought to represent (a non-hadrosaurid styracosternan) and the age and geography of Lark Quarry, we suggest that the track-maker may have been a dinosaur similar to Muttaburrasaurus langdoni. 相似文献
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诸城市恐龙化石资源非常丰富,全市共发现恐龙化石产地30多处,其中典型的化石产地有"库沟化石长廊"、"恐龙涧隆起带"、"臧家庄化石层叠区"和"黄龙沟足迹化石群"。当地政府为了保护这些珍贵的化石资源,采取了许多行之有效的保护措施,但在保护过程中发现仍然存在一些不足之处。该文根据目前保护现状,针对保护中存在的主要问题,进行深入分析查找原因,提出可行性措施。 相似文献
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A Corythosaurus skull (UALVP 13) was collected in 1920 from what is now Dinosaur Provincial Park in southern Alberta, Canada and was designated the holotype of Corythosaurus excavatus, a new hadrosaur species by Gilmore (1923). In 1992, a previously uncovered, weathered, headless skeleton was found. This was collected in 2012 by the University of Alberta as there was potential it could belong to the holotype skull. In addition, an isolated hadrosaur dentary had been found in 1992 close to the articulated postcranial skeleton and may be one of the missing jaws of Corythosaurus excavatus. The hypothesis that it may be the skeleton of the holotype of Corythosaurus excavatus is tested using anatomical information and statistical analyses. Statistical comparisons suggest it is possible that the skull and dentary belong to the same specimen. Furthermore, bivariate plots and percentage prediction errors also indicate that the postcranial material could belong to the UALVP 13 skull. Because many large vertebrate fossil specimens (even types) are not always collected in their entirety, this method may be used as a line of evidence to determine whether independently collected specimens potentially belong to the same individual. The problems described herein highlight the need to collect specimens in their entirety, and for good field documentation, including the spatial and stratigraphic context of all finds. 相似文献
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应用医疗ＣＴ扫描法观察恐龙蛋化石，可清晰地分辨出卵形，卵壳，卵蛋白，卵黄及充填的矿物等结构，并可测出各部具体数据，为恐龙蛋化石的研究开辟了一个新的途径。 相似文献
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四川安岳恐龙化石埋藏地遂宁组、蓬莱镇组中遗迹化石及其环境意义 总被引：1，自引：1，他引：0
在四川安岳恐龙化石埋藏地上侏罗统遂宁组、蓬莱镇组地层中,发现了Scoyenia,Palaeophycus,Akolithos,Muensteria,Planolite,Cylindricum,Thalassinoides,Arenicolites等8个遗迹属,共10个遗迹种,归属为Scoyenia遗迹群落。遗迹群落与沉积构造特征表明遂宁组、蓬莱镇组沉积环境为泛滥平原,其中恐龙化石埋藏于泛滥平原上洪泛湖泊的滨湖砂岩之中。恐龙集中埋藏的原因可能是其死亡后被搬运于滨湖环境。 相似文献
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胶东诸城晚白垩世恐龙骨骼化石地球化学及埋藏学研究 总被引：1，自引：0，他引：1
胶东诸城发育了世界罕见的晚白垩世中晚期恐龙化石集群埋藏点,主要分布在诸城市东南的库沟、恐龙涧、西见屯和臧家庄。本文通过薄片鉴定、电子探针、常量、微量和稀土元素分析等方法技术,系统研究了诸城恐龙骨骼化石微观特征与地球化学特征,分析了恐龙骨骼埋藏成岩过程,厘定4个化石集群埋藏层的相对层位关系和骨骼沉积物来源方向,探讨了恐龙死亡的可能原因。研究表明,研究区恐龙骨骼化石主要矿物成分为磷灰石和方解石,也零星含有Fe、Mn、BaSO4及SiO2等矿物成分;骨骼化石和围岩主量、微量与稀土元素分析显示,CaO、P2O5、F、REE、Y、Sr和Ba、U高值且远高于围岩,其中CaO、P2O5、F、Sr和Ba的高值是由于原始骨骼组成中这些元素背景含量高,而REE、Y及U的异常高值是成岩过程中吸附作用所致;骨骼中Rb、Th、Nb、SiO2、Al2O3、TiO2、Zr、Hf含量低于围岩是由于它们属于亲沉积碎屑元素,都来自母岩的风化产物;骨骼化石中稀土元素表现为轻稀土富集型,稀土配分模式与上地壳相似,并具有Eu轻微正异常和Ce负异常特点;研究认为,骨骼与围岩较高的Sr、Ba含量及稀土元素异常系源于干旱气候与氧化环境的浅埋藏成岩作用;依据不同化石点骨骼中磷灰石矿物与方解石矿物组成的对比、骨骼与围岩主量元素分子风化率指数及REE、HREE、LREE与(La/Yb)N、(Ce/Yb)N和(La/Sm)N、δEu、δCe等参数的对比,研究区4个集群埋藏的恐龙化石层相对层位关系由下至上分别厘定为库沟、西见屯、恐龙涧与臧家庄;骨骼围岩沉积物源主要来自下伏青山群火山岩与莱阳群沉积岩的剥蚀产物;研究区上白垩统红土崖组下部不到100m厚的地层中恐龙化石异地集群埋藏层的多次出现表明,集群埋藏不是一个简单孤立事件,恐龙的死亡也可能受制于干旱气候的影响,特别是环境背景的Sr和Ba等元素有可能是环境毒素;干旱缺水、缺少食物、有毒元素散布可以导致恐龙集群死亡;骨骼在季节性洪水或阵发性泥石流的作用下由诸城西北向东南搬运和堆积。 相似文献
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A Yanji Basin tracksite in the Cretaceous Tongfosi Formation in the Yanbian Korean Autonomous Prefecture, Jilin Province was reinvestigated twenty years after the original study.The re-examination confirms the presence of tracks tentatively referred to ornithopods and theropod tracks including several not previously reported. In addition to the main track-bearing level, a second footprint horizon was identified from which a probable ornithopod track was collected. Some of the formerly identified tracks were documented using photogrammetry, whereas others that had been collected, eroded, buried or obscured by dense vegetation. The age of the track-bearing beds is inferred to be late Albian to early Cenomanian. Comparison with track-bearing units of the same age in Shandong, China, and Korea indicated quite different compositions of track assemblages. In the case of the Korean sites the differences may be facies related. While the Korean ichnofauna is characterized by the co-occurrence of ornithopod, sauropod and tridactyl theropod tracks with didactyl dromaeosaurid, Minisauripus (small theropod), pterosaur and avian tracks, the latter four are absent in the Tongfosi assemblage. This could reflect a restricted environment being not favourable for activities of these trackmakers or simply a preservational bias. 相似文献