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1.
本文记述了发现于宁夏六盘山地区的恐龙足迹化石。共计5个化石点,分别位于宁夏六盘山地区固原市隆德县和泾源县,赋存地层为下白垩统六盘山群和尚铺组、李洼峡组和马东山组,包括蜥脚类和鸟脚类恐龙足迹化石,其中以蜥脚类为主。足迹可识别的有4条行迹,其中,隆德县香水镇行迹所代表的恐龙个体较小,臀高仅1.44m,其余3组行迹代表的恐龙较大,臀高在2.79~3.27m之间;鸟脚类恐龙臀高约为0.48 m,为小型鸟脚类恐龙。采用Alexander的速度计算方法对造迹恐龙的速度进行研究,表明六盘山地区蜥脚类造迹恐龙速度为0.34~1.41m/s之间,复步长与臀高的比值小于2,均为正常行走状态。足迹保存层面岩性主要为粉砂质泥岩、细砂岩,具水平层理、波痕、泥裂、雨雹痕等沉积构造,含植物碎片化石,并发育有大量的无脊椎动物潜穴化石。根据岩性及沉积构造判断,造迹恐龙活动环境为离湖岸较近的浅水地带。  相似文献   

2.
Here we report a large dinosaur tracksite from an extensive fluvial sandstone surface in the Lower Cretaceous Jiaguan Formation of Sichuan Province, China. The site contains over 250 individual tracks comprising at least 18 recognizable trackways, including the longest theropod trackway (cf. Eubrontes) known from China. This exceptional theropod trackway consists of 81 successive footprints covering a distance of 69 m. The tracks are well-preserved and are expressed both as true tracks on the main “upper” surface and as transmitted undertracks on a locally exposed “lower” bed. Also recorded are six other theropod trackways, including small Grallator-like ichnites, eight sauropod trackways (cf. Brontopodus), and three small ornithopod (cf. Ornithopodichnus) trackways with a parallel orientation, which may indicate gregarious behavior. Several trackways of a larger theropod trackmaker show pes imprints with elongated traces of the metatarsals, suggesting extramorphological (substrate-controlled) variation and/or plantigrade posture, which is here interpreted as indicating a change in gait assumed in response to deep and soft sediment. The assemblage indicates a diverse dinosaur fauna in the Lower Cretaceous Sichuan Basin with variously sized theropods, sauropods, and ornithopods. The late occurrence of footprints of the Grallator-Eubrontes plexus in Lower Cretaceous strata is further evidence of the extended stratigraphic range of this morphotype and the distinct palaeobiogeographic distribution of these trackmakers in East Asia.  相似文献   

3.
In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well. Actually, the dinosaur footprints were found by local inhabitants much earlier in history, but not for science. The slabs bearing the dinosaur footprints were collected for domestic use, such as building stones, millstones, cellar covers, sheepfold fences, windlass holders, etc. This paper is to describe the dinosaur footprints on both sides of three slabs used for cellar covers, sheepfold fences and windlass holders by the local people. 24 dinosaur footprints and 4 trackways have been recognized and all of them belong to theropod. Four kinds of dinosaur footprints are identified, including 1 new ichnogenus and 2 new ichnospecies: (1) Shanbeipus caudatus ichnogen. et ichnosp. nov.; (2) Pengxianpus yulinensis ichnosp. nov.; (3) Eubrontes ichnosp; (4) Kayentapus ichnosp. Dinosaur-footprint-bearing beds were initially identified as the Fuxian Formation of the Lower Jurassic. Multipal dinosaur footprints associated with fragment plant fossils suggest a humid fluvio-lacustrine environment setting in the Ordos Basin during the early period of the Jurassic.  相似文献   

4.
A diverse assemblage of late Pleistocene marsupial trackways on a lake bed in south-western Victoria provides the first information relating to the gaits and morphology of several megafaunal species, and represents the most speciose and best preserved megafaunal footprint site in Australia. The 60–110 ka volcaniclastic lacustrine sedimentary rocks preserve trackways of the diprotodontid Diprotodon optatum, a macropodid (probably Protemnodon sp.) and a large vombatid (perhaps Ramsayia magna or ‘Phascolomysmedius) and possible prints of the marsupial lion, Thylacoleo carnifex. The footprints were imprinted within a short time period, demonstrating the association of the taxa present, rather than the time-averaged accumulations usually observed in skeletal fossil deposits. Individual manus and pes prints are distinguishable in some trackways, and in many cases some digital pad morphology is also present. Several parameters traditionally used to differentiate ichnotaxa, including trackway gauge and the degree of print in-turning relative to the midline, are shown to be subject to significant intraspecific variation in marsupials. Sexual dimorphism in the trackway proportions of Diprotodon, and its potential for occurrence in all large bodied, quadrupedal marsupials, is identified here for the first time.  相似文献   

5.
藏东昌都地区阿涅塘化石点中侏罗世达布卡组滨湖相紫红色中-细砂岩中,发现以凸形迹完好地保存的4层恐龙足迹,包括Grallator类、大型兽脚类、小型兽脚类和小型蜥脚类等足迹类型,并构成两列完美的行迹. 组成行迹T1的4个Grallator类足迹被命名为Grallator anietangensis isp. nov.,对其进行了详细的形态学分析,并讨论了造迹恐龙的大小和运动状态,这是Grallator类足迹在西藏地区的首次发现. 组成行迹T2的9个大型兽脚类足迹被归为Theropoda igen. et isp. indet.,对该类足迹进行了形态描述和功能分析;这类足迹在中国是首次记录,其连续且清晰的尾迹表明造迹者并非处于正常运动状态,而是应对某种特殊境况的特别行为方式,即其正以昂起的前躯一边观察,一边以极低的速度前进,因前躯昂起,尾部相应下垂,从而留下尾迹. 两列行迹均显示出造迹者正沿古昌都湖岸前进. 中国迄今所发现的恐龙骨骼和Grallator类足迹化石主要表现为以西南地区为中心,再向四周不断发散的扩散模式,但Grallator类足迹化石综合提供的信息显示恐龙动物的扩散速度比骨骼化石反映的速度更快.   相似文献   

6.
7.
One hundred and forty six dinosaur footprints occur on the Cenomanian outcrop of Fenoliga. They are arranged in six trackways and six footprint groups (a–f). Two basic footprint types can be distinguished: firstly, large circular-elliptical sauropod footprints, forming four trackways (I, III, V, VI) and five footprint groups (a–e), and secondly, smaller, tridactyl theropod footprints forming two trackways (II and IV) and one footprint group (f). Three type specimens, one sauropod and two theropod, were determined during the course of the work. Since no dinosaur bones have been discovered in the Cenomanian rocks of Istria so far, these findings are outstandingly important in the analysis of the regional dinosaur fauna.  相似文献   

8.
1923年Nopcsa命名的Emydichnium是龟类足迹最早的报道,后来其他一些中生代的足迹也被陆续报道描述。但是大多数化石只显示出或多或少的明显爪印或者划痕,无法反映造迹者足部较为全面的生物学特征。山东诸城皇龙沟足迹点保存了早白垩世大量形态多样的龟类足迹,本文对其中一保存较好,能够反映足部生物学特征的龟类足迹进行了详细描述,并依据数据统计与莱阳足迹Liayangpus进行对比,显示两者存在明显不同。诸城的龟类足迹区别于以往发现的龟类足迹,因此根据其形态建立新种:完整诸城足迹Zhuchengichnites perfectus。本文亦对中国发现的龟类足迹化石点的层位、保存类型等进行了总结。  相似文献   

9.
张艳霞  孙业君  陈军  崔卫生  陈树清 《地质论评》2022,68(5):2022102015-2022102015
1923年Nopcsa命名的Emydichnium是龟类足迹最早的报道,后来其他一些中生代的足迹也被陆续报道描述。但是大多数化石只显示出或多或少的明显爪印或者划痕,无法反映造迹者足部较为全面的生物学特征。山东诸城皇龙沟足迹点保存了早白垩世大量形态多样的龟类足迹,本文对其中一保存较好,能够反映足部生物学特征的龟类足迹进行了详细描述,并依据数据统计与莱阳足迹Liayangpus进行对比,显示两者存在明显不同。诸城的龟类足迹区别于以往发现的龟类足迹,因此根据其形态建立新种:完整诸城足迹Zhuchengichnites perfectus。本文亦对中国发现的龟类足迹化石点的层位、保存类型等进行了总结。  相似文献   

10.
简要报道了新近首次在冀西北张家口尚义地区发现的恐龙足迹。野外地质调查发现,恐龙足迹赋存于尚义晚中生代盆地侏罗系—白垩系后城组顶部。恐龙行迹呈近东西向展布,由数十个足迹构成。初步研究表明,造迹者分别属于兽脚类和蜥脚类恐龙,由西向东行进。足迹中包括兽脚类足迹70余个,组成数个行迹;蜥脚类足迹15个,构成1列行迹。蜥脚类足迹特征显示其可能属于游泳状的行迹。华北北部土城子组/后城组发育于燕辽生物群—热河生物群更替演化时期(晚侏罗世—早白垩世早期),以往在该时期沉积物中罕见脊椎动物骨骼化石。近年来华北北部土城子组/后城组中频繁发现的恐龙足迹表明,燕辽生物群—热河生物群更替演化时期发育着以恐龙为代表的脊椎动物群。该发现将有助于进一步了解土城子组/后城组沉积时期恐龙属种的多样性及其生物古地理环境。晚侏罗世—早白垩世早期沉积古地理和古生态环境及其与恐龙动物群发育的研究有助于揭示陆地生物群更替演化和环境的关系。  相似文献   

11.
记述了广东省南雄盆地上白垩统主田组3组恐龙行迹,由杨梅坑足迹点的足迹命名了南雄鸭嘴龙足迹(Hadrosauropodus nanxiongensis ichnosp. nov.)一新种;古市足迹点的足迹归入鸭嘴龙足迹一未定种(Hadrosauropodus isp.)。这是中国鸭嘴龙足迹属的首次描述,将该足迹的分布从北美拓展至中国,并为南雄盆地存在大型的鸭嘴龙提供了新的化石证据。还整理了中国已描述的大型鸟脚类足迹:中国足迹(Sinoichnites)被定为非正式的塑模标本;扬子足印(Yangtzepus)被归入兽脚类足迹;禽龙足迹(Iguanodonopus)被认为是裸名,归入禽龙足迹(Iguanodontipus);嘉荫足迹(Jiayinosauropus)增加了新材料并得以具体描述;内乡足迹(Neixiang footprint)得以重新描述。  相似文献   

12.
李素  周瑶琪  姚旭  李超 《地质论评》2012,58(3):434-443
鲁东诸城皇华镇地区下白垩统莱阳群发现大量恐龙足迹化石(兽脚类、鸟脚类、蜥脚类).足迹化石赋存地层为龙旺庄组灰绿色、黄绿色泥质细砂岩、粉砂岩,为滨浅湖—河流相沉积环境.足迹特征显示:蜥脚类恐龙体重大,四足行走,前后足迹面积相近,似椭圆形;鸟脚类和兽脚类恐龙为两足行走,足迹为三趾型;兽脚类恐龙体重最轻、数量最多.三大类恐龙...  相似文献   

13.
Twelve trackways of ornithopods from Lower Cretaceous lacustrine margin deposits of the Jindong Formation represent new dinosaur trackways described from Korea. The site, discovered during highway construction, was rescued by removing the most important trackways to the Korean Natural Heritage Center in Daejeon, where they are on permanent display. The new ichnotaxon Ornithopodichnus masanensis ichnogen. et ichnosp. nov. is recognized as a distinctive robust tridactyl track, slightly wider than long (l/w ratio = 0.91), with positive (inward) rotation. The toe prints are very thick, broad and U-shaped, resulting in a trefoil outline with a smoothly rounded hind margin. Digit III is short and projects anteriorly much less than digit II and IV (= weak mesaxony). Divarication of digits II-IV is about 70° with interdigital angle II-III larger than III-IV. Trackway width is narrow and the stride length/track length ratio is about 4.2–4.6. The Ornithopodichnus trackways evidently represent gregarious blunt-toed Iguanodon-like bipedal ornithopods, although poorly preserved manus traces are discerned in a few trackways. Ornithopodichnus is distinct from other well known iguanodontid tracks that display much stronger mesaxony and indicates a polarity in ornithopod foot morphology that can be verified by reference to known foot skeletons.  相似文献   

14.
More than 125 footprints of theropods from the Cretaceous Longwangzhuang Formation have been mapped in a preliminary study at a site in the Zhucheng region of China. The tracks represent at least three morphotypes. The largest morphotype is a large theropod (footprint length ∼30 cm) represented by a single trackway and an isolated natural cast. At least 10 trackways assigned to the new ichnospecies Corpulentapus lilasia represent a medium-sized biped (footprint length ∼13 cm) with very short, wide, robust, ‘tulip-shaped’ tracks and long steps (∼5 × footprint length), and a short central digit (III) indicating weak mesaxony. Corpulentapus trackways are narrow and theropod-like even though track morphology is convergent with the footprints of some ornithopods. The third morphotype, made by a medium-sized grallatorid track maker (ichnogenus Paragrallator), is about the same size (∼13 cm) as the robust morphotype, but far more elongate and gracile, with an elongate central digit (III) indicating strong mesaxony. This ichnotaxon requires detailed comparison with Grallator sensu stricto. The contrast in morphology between the two common morphotypes is striking and demonstrates that two distinct medium-sized taxa of presumed theropod affinity frequented the same habitat in significant numbers.  相似文献   

15.
A dinosaur tracksite was discovered in Batha on the side of the road from Harissa to Ghosta (Keserwan, Lebanon). About ten trackways are exposed at the top of two beds of Lower Cretaceous limestones over an area of approximately 1000 m2. These footprints were probably made by at least two dinosaur species, Sauropoda and either Theropoda or Ornithopoda. The site, which is the first record from Lebanon, should be protected to allow further scientific investigations.  相似文献   

16.
The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauropodomorphs. All the trackways are sub parallel likely indicating gregarious behavior. One theropod track(cf. Grallator) was recorded. The sauropodomorph tracks predominantly represent quadrupedal progression(Morphotype A), and footprint morphology is similar to the ichnospecies Liujianpusshunan, characterized by outward pes rotation. Three trackways indicate bipedal progression, and two of these(Morphotype B) indicate inward pes rotation, accompanied by elongate pes digit scratch marks. For the latter phenomenon three possible scenarios are discussed:(1) significant rotation changes accompanying changes in gait,(2) swimming behavior,(3) formation of undertracks.Sedimentological evidence indicates the tracks were made on a linguloid rippled, muddy, immature sandstone substrate characterized by significant differences in substrate consistency across the trackbearing surface. Microbially induced sedimentary structures(MISS) characterized by distinctive wrinkle marks indicate a stressed, probably semi-arid, paleoenvironment that was not conducive to habitation by invertebrate organisms. This is consistent with other evidence that Lower Jurassic sauropodomorph tracks are often associated with semi-arid paleoenvironments.  相似文献   

17.
A large track site with multiple,well-preserved trackways of an Early Jurassic quadrupedal ornithischian dinosaur is the first report of Moyenisauripus-like trackways from Asia,herein named Shenmuichnu...  相似文献   

18.
A previously unknown and morphologically distinct pentadactyl mammal track was recovered from the Upper Cretaceous (Maastrichtian) Laramie Formation at the Fossil Trace site, a National Natural Landmark which is the type locality for Schadipes crypticus, the only named mammal track known from North America. The track is different, and larger than S. crypticus, and thus is evidence of a diversity of mammal trackmakers at this site. Although Cretaceous mammal tracks are very rare, preliminary indications are that those currently known are all morphologically distinct and therefore indicative of a global diversity of different trackmakers, as the body fossil record suggests. Lack of well-preserved mammal trackways with morphologically distinct manus and pes footprints hampers efforts to name diagnostic ichnotaxa.  相似文献   

19.
The low-gradient Red River is a rapidly migrating, sinuous stream with easily erodible banks. Avulsion is common at many scales, from individual meander bends that are cut off to major sections of the river that form multiple, complex meander belts. The present meander belt can be subdivided into mappable landforms—termed phases—that are associated with river courses of different ages and thus associated with archeological sites of different ages. Within the study area two phases are present. The younger Modern meander belt phase has formed within the past 0.2–0.3 ky, precluding preservation of prehistoric archaeological sites. Any protohistoric artifacts that may have been preserved in this meander belt phase would be deeply buried because as much as 2 m of the vertical accretion sediment has accumulated between artificial levees in <0.1 ky and 1–2 m of sediment has accumulated beyond the artificial levees in <0.2 ky. Archeological site preservation in this highly mobile fluvial end member can be used as a predictor for other, similar streams. A large prehistoric site is preserved on an older (0.5–1 kya) Late Prehistoric meander belt phase associated with an abandoned river course. In the study area a Fourche Maline 7 period (A.D. 800–900) through Caddo IV period (ca. A.D. 1500–1700) archeological site (3MI3/30) is preserved on this slightly higher altitude portion of the flood plain. At locations proximal to the river, the site may be buried by overbank sediment 0.4 m thick, but at more distant locations the site is at the surface or only buried by thin overbank sediment because of low sedimentation rates (0.04 cm yr−1) over the span of a millennium. Sites, such as 3MI3/30, that are occupied contemporaneous with overbank sedimentation may be stratified; however, localized erosion and removal of some archeological material may occur where channelized flow crosses the natural levee. © 1998 John Wiley & Sons, Inc.  相似文献   

20.
In the 80's, Leonardi treated the presence of a vertebrate ichnological locality from the Barremian Corda Formation, Parnaíba Basin, on the left bank of the Tocantins river, near of the São Domingos town, Itaguatins, State of Tocantins, Brazil. Originally, the record was composed of at least seven in situ trackways, accounting for fifty six tracks. Since 2011, the Hydroelectric Power Plant do Estreito has begun to work, causing the development of a water reservoir 160 km upstream to the ichnological site, causing periodic and highly energetic floods over the footprints-bearing level and altering it. The imprints are poorly to moderate preserved, but it is possible to distinguish the general morphology and the spatial arrangement of the footprints. The specimens are represented by pes imprints, mostly circular to subcircular, with no digital and claw impressions. No distinguishable manus imprints are present. The trackways are relative narrow with respect to the size of the tracks, so they are considered into the Parabrontopodus-like category. The São Domingos tracks have been originally assigned to iguanodontid dinosaurs, and posteriorly related to a sauropodian origin. This idea is herein accepted, particularly to a basal sauropod, basal macronarians, or diplodocoids. Up to date, the tracks from the São Domingos locality are the only vertebrate fossil record from the Corda Formation, meaning an important contribution to the Cretaceous ichnofauna from South America.  相似文献   

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