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51.
A new theropod dinosaur, Shidaisaurus jinae gen. et sp. nov., has been described on the basis of an incomplete skeleton. The specimen was found near the base of the Upper Lufeng Formation (early Middle Jurassic) in Yunnan, China. It is the first theropod dinosaur from the Middle Jurassic of Yunnan. Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase, axis, and pelvic girdle. The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China. Most Chinese taxa of Jurassic theropod dinosaurs have not been well described; a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurus jinae. 相似文献
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53.
采用扫描电镜、电子探针和X射线粉末衍射分析技术,研究了浙江天台盆地TB-1恐龙蛋化石的结构和组分。初步了解这个含似蛋白和蛋黄的恐龙蛋化石的结构和组分为;含铁钛的硅酸盐矿物售合体(蛋壳表层)、灰褐色方解石(蛋壳内层)、浅米黄色方解石(壳内矿物层)、白色石膏(腔内似蛋白矿物)和米黄色萤石(腔内似蛋黄矿物)。 相似文献
54.
利用显微镜和碳同位素分析法对自河南西峡盆地晚白垩世的16枚恐龙蛋化石进行了研究。在显微镜下观察到恐龙蛋化石壳由原生碳酸盐矿物和次生碳酸盐矿物两部分组成。利用图像分析法得到了两者所占的比例分别为60.5%和39.5%。恐龙蛋内充填的次生碳酸盐矿物的δ^13C值在-5.63‰ ̄-5.68‰之间,平均为-5.65‰。恐龙蛋化石壳的δ^13C同位素值在-5.88‰ ̄-7.79‰之间。经计算,获得了恐龙蛋壳 相似文献
55.
辽宁黑山恐龙化石的发现及其地层意义 总被引:3,自引:0,他引:3
在辽宁省黑山县八道壕煤矿沙海组下部发现一颗恐龙牙齿化石,鉴定为Asiatosaurussp.,时代属早白垩世,对我国北方热河生物群时代归属研究及侏罗系-白垩系界线的划分都具有重要意义。 相似文献
56.
由恐龙化石论晚白垩世事件沉积 总被引:2,自引:0,他引:2
本文根据晚白垩世恐龙化石的分布结合地层学特征,初步提出了这套含有恐龙化石的晚白垩世地层属于事件沉积的观点,并认为导致这次事件沉积的原因可能是由天体撞击地球产生的强海啸形成。 相似文献
57.
河南西峡盆地恐龙蛋化石及略论恐龙绝灭问题 总被引:3,自引:0,他引:3
西峡盆地晚白垩世红色陆相碎屑岩系地层中(包括高沟组、马家村组、寺沟组),产有类型多、数量大、成窝性好的恐龙蛋化石。已发现有7科8属10种。自下而上,恐龙蛋的种类、数量、含蛋层数、蛋窝均大幅度地减少,由高沟组内5科67种,约10层含蛋层,至寺沟组内仅存1科1属2种,含蛋层为2层。恐龙绝灭原因的研究,已有30种以上的学说或观点,但这些观点都不能圆满地解释恐龙的绝灭问题。恐龙的绝灭应该是多因素的,既有地外的灾变,又有地内,生物本身生理的因素。在内、外因等诸因素的共同作用下,恐龙才有可能绝灭。 相似文献
58.
中国恐龙蛋化石及其生态地层浅析 总被引:2,自引:0,他引:2
文章系统地对中国恐龙蛋化石的地理分布作了总结,并将恐龙蛋化石类型归纳为9科,13属,21种。在此基础上,着重分析了恐龙蛋化石古生态特征,分别从蛋化石的排列方式,恐龙产蛋的方式,不同类型蛋化石间及蛋化石与骨骼化石共生几方面作了探讨,并进一步阐述恐龙蛋化石在晚白垩世地层划分对比所具有的直接指示意义 相似文献
59.
WANG Baopeng LI Jianjun BAI Zhiqiang GAO Junmin DONG Shurong HU Bailin ZHAO Suiqin CHANG Jieqiong 《《地质学报》英文版》2016,90(1):1-18
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
60.
A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints from Xinjiang Province in northwestern China. More than 150 tridactyl theropod dinosaur footprints are preserved as positive hyporeliefs on the lower bedding plane of a fine-grained sandstone body. Most of the footprints are isolated and appear to be randomly distributed. Some show well defined phalangeal pads, heels and rarely indistinct impressions of the distal part of the metatarsus. Two distinct morphotypes are present: a larger type with relatively broad pads shows similarities to Changpeipus and Megalosauripus, and a slightly smaller, slender and gracile type which is similar to Grallator, Eubrontes and Anchisauripus. In both morphotypes, digit III is the longest with a length between 11.4 and 33.6 cm. A single imprint shows prominent scratches, probably formed during slipping of the track maker. 相似文献