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1.
The Sinuiju Formation in Paekto-dong, Sinuiju City in the Democratic People's Republic of Korea has yielded Mesozoic nonmarine bivalve fossils, which is the first occurrence of such in the DPRK. Based on these fossil specimens, a new Cretaceous bivalve assemblage, the Arguniella yanshanensis-Sphaerium anderssoni Assemblage is erected. This assemblage includes Arguniella yanshanensis, A. lingyuanensis and Sphaerium anderssoni and can be compared with the Jehol Biota. The age of the Sinuiju Formation is also clarified and on the basis of the bivalves and the presence of a Eosestheria–Ephemeropsis–Lycoptera(E–E–L) assemblage, the formation is not Upper Jurassic, but Lower Cretaceous in age. 相似文献
2.
Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baishan Basin, southeastern Jilin. The faunal remains from this formation distinctly belong to the Early Cretaceous Lycoptera–Ephemeropsis–Eosestheria assemblage of the Jehol Biota. Based on the gross leaf morphology and epidermal structures, two new species and one indeterminate species of genus Solenites(Czekanowskiales), S. baishanensis sp. nov., S. gracilis sp. nov. and S. sp. are described in this paper. This is the first fossil plant of Czekanowskiales reported from this new fossil locality of the easternmost area of the Late Mesozoic Jehol Biota, China. The new discovery contributes to improve our knowledge for understanding of leaf morphology, epidermal characters and diversity of this genus during the Early Cretaceous time, and extends geologic and geographic distribution of Solenites in northern China and Eurasia. Along with consideration of associated plant and faunal assemblages and sedimentology, we suggest that the regional climate was warm and moderately humid with seasonal temperature and precipitation variations in warm–temperate zone during the Early Cretaceous. 相似文献
3.
A New Specimen of Liaoceratops yanzigouensis (Dinosauria: Neoceratopsia) from the Early Cretaceous of Liaoning Province, China 
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下载免费PDF全文 A new specimen of basal neoceratopsian dinosaur Liaoceratops yanzigouensis is described. The specimen comes from the Lujiatun Bed of the Lower Cretaceous Yixian Formation in Beipiao City of western Liaoning Province, and is represented by a very well preserved three-dimensional partial skull and mandible. It is also the smallest among the three specimens of L. yanzigouensis, and several features in the new specimen, such as the short preorbital length and the round rostroventral orbital rim, can be ontogenetically-related. The superb exposure of the palatal complex may be caused by the removing of its brain by a small predator in the contemporary Jehol Biota. 相似文献
4.
LI Yunfeng HUANG Wei WANG Hongshan David L. DILCHER TAN Xiao LI Tao NA Yuling SUN Chunlin 《《地质学报》英文版》2018,92(4):1649-1650
正Objective The Jehol Biota,a world-famous Early Cretaceous fossil Lagerst?tte characterized by the traditional Eosestheria-Ephemeropsis-Lycoptera(EEL)assemblage,has a wide distribution over most parts of northern China,the coastal area of southeastern China,southeastern Mongolia,Transbaikalian area of Russia,Korea and Japan(Shao et al.,2017).The Baishan Basin,situated in 相似文献
5.
Selection and Basic Properties of the Buffer Material for High-Level Radioactive Waste Repository in China 总被引：1，自引：0，他引：1
WEN Zhijian 《《地质学报》英文版》2008,82(5):1050-1055
Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposing high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. It is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation properties, thermal conductivity, chemical buffering property, canister supporting property, and stress buffering property over a long period of time. Bentonite is selected as the main content of buffer material that can satisfy the above requirements. The Gaomiaozi deposit is selected as the candidate supplier for China＇s buffer material of high level radioactive waste repository. This paper presents the geological features of the GMZ deposit and basic properties of the GMZ Na-bentonite. It is a super-large deposit with a high content of montmorillonite （about 75 %）, and GMZ-1, which is Na-bentonite produced from GMZ deposit is selected as the reference material for China＇s buffer material study. 相似文献
6.
Lower brachyceran flies are abundant in the Late Mesozoic of China. Many extant and extinct members of that have been found in Inner Mongolia, Liaoning, Hebei and Shandong provinces. A new family, Origoasilidae fam. nov., belonging to the lower Brachycera, is built based on a new specimen from the Yixian Formation and is a representative of the Jehol Biota. The new endemic Mesozoic family possesses several unique characters in the wing. The relationship among the Origoasilidae fam. nov. and relative known lower brachyceran flies has been discussed 相似文献
7.
Yanjiahella gen. nov., a distinctive fossil taxon from the Early Cambrian Yanjiahe Biota in Yichang, Hubei Province, is characterized by: 1) an overall body plan composed of a stalk and a calyx (also arms in some species); 2) a stalk with closely spaced, transverse wrinkles and a medial, longitudinal ridge; and 3) a calyx preserved with three-dimensional radiating striations, as well as a probable madreporite in some specimens. Three species that can be assigned to this genus, which are Y. ancarpa sp. nov., Y. monocarpa sp. nov., and Y. biscarpa sp. nov. Yanjiahella is comparable to certain echinoderm taxa in terms of morphology and some biological structures, which might indicate the early evolution and diversification of ancestral echinoderm lineages from the early Early Cambrian Yangtze Platform. The discovery of putative echinoderms in the Yanjiahe Biota provides significant clues about the origination and evolution of the deuterostome phylum Echinodermata. 相似文献
8.
Abstract: A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups: 15 specimens into a winged fruit of Fraxinus, and one specimen of Liriodendron. The most samaras (13 specimens) were identified as Fraxinus oishii, which is characterized by narrowly ovate or ovate–elliptic shapes that are 2.7–3.6 cm in length and 0.7–1 cm in width (l/w ratio=3.4–4). The apexes of the Fraxinus oishii samara are round or slightly emarginated, and a seed of the samara is always located at the base, of which the general shape is narrow rhombic-ellipsoidal. The seed is 1.2–2 cm long and 0.5–0.7 cm wide. Two specimens are different from the samara of Fraxinus oishii. They have a 6.6 length/width ratio (3.3 cm long and 0.5 cm wide), and thus, are temporarily classified into the Fraxinus sp. One specimen was recognized as a winged seed of Liriodendron meisenense. The wing is broadly lanceolate to elliptic in shape, has a smooth, acute apex, and is approximately 3 cm long and 0.7 cm wide. Samaras of Fraxinus oishii and Liriodendron meisenense were early reported from the Middle Miocene deposits from North Korea, but these specimens are the first discovery in South Korea. Further study of the Duho Formation may connect flora relationships between North and South Korea. 相似文献
9.
Dinomischus from the Middle Cambrian Kaili Biota, Guizhou, China 总被引：2，自引：0，他引：2
PENG Jin ZHAO Yuanlong LIN Jih-Pai 《《地质学报》英文版》2006,80(4):498-501
Dinomischus is a rare solitary epifaunal suspension feeder. The over-all morphology of Dinomischus consists of a conical calyx surrounded with elongate bracts and an elongate stem. Visceral mass and stomach sac are evident in the body cavity. Dinomischus is interpreted as a primative ancestor of living entoprocts based on similarities in morphology and mode of life. Previously, Dinomischus is only known in two localities： the mid-Middle Cambrian Burgess Shale Biota and the Early Cambrian Chengjiang Biota. A single specimen of Dinomischus cf. D. isolatus Cowry Morris, 1977 from the Kaili Biota, Guizhou, China is reported here. The discovery of Dinomischus in the Kaili Biota extends its geographical range and indicated that the rare Dinomischus could tolerate deeper water settings during the Middle Cambrian. 相似文献
10.
<正>The third biological radiation refers to the Middle Triassic biological radiation in the world.In 2007,the China Geological Survey during field investigations of the project"Regional Geological Survey in Datong,Guishan,Luoping County and Pengzha at a scale of 1:50000 in Yunnan Province"first discovered and named the Luoping Biota(Fig.1).This Middle Triassic biota emanates from 相似文献
11.
20世纪90年代以来,中国辽宁西部及其邻区晚中生代热河生物群和道虎沟生物群研究取得了令世人瞩目的成果,尤其是在鸟类起源及其早期分异、羽毛起源及其早期演化模式、真兽类起源与早期兽类的生态辐射、被子植物起源等研究方面获得了许多重大进展。截至2006年底,共有46篇关于热河生物群的研究论文以及3篇道虎沟生物群的研究论文发表在世界著名的《自然》和《科学》杂志上,其中第一作者单位为中国科研机构的论文数量分别达39篇和2篇。《自然》和《科学》杂志是世界上自然科学领域两个国际性学术周刊,其覆盖范围广、传播速度快、读者群广泛,其连续刊登热河生物群和道虎沟生物群的研究论文,使这些重要研究成果在短时期内为全世界的学者所认可和接受,为推动该两个重要生物群的研究发挥了重要的作用。 相似文献
12.
From a newly discovered Early Cretaceous fossil site at the Sanlianhe Coal Mine in Tahe County, Heilongjiang Province, the most northern area in China, two freshwater fossil fish had been recovered. This paper reports their classifications and implications regarding the palaeobiogeography of the Jehol Biota. The fish assemblage consists of Yanosteus sp. (Acipenseriforms) and Sinamia sp. (Amiiformes). Both are important members of the well known Jehol Biota, and their occurrence supports the correlation of the Yiliekede Formation at Sanlianhe Coal Mine site with the Jiufotang Formation of West Liaoning. The remains of the Yanosteus sp. from this locality is the first known record of the genus other than in the Yan‐Liao area of China, and the specimens of Sinamia sp. is quite similar to what may be a new species of Sinamia from West Liaoning. The new fossil site represents the most northern site that is undoubtedly part of the extent of the Jehol Biota as currently understood. The northern Great Xing'an Range area is an important region that may link correlations between the Early Cretaceous continental biotas of China, Mongolia and Russia. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
13.
热河生物群是分布于亚洲东部早白垩世的著名古生物化石群,地质时代距今120~131 Ma. 早期研究认为,热河生物群主要分布于中国冀北、辽西等地区. 直到20世纪80年代内蒙古地区开展专题区域地质研究,才陆续发现了许多新的热河生物群化石分布区域和重要的化石产地. 通过对内蒙古自治区东、西部白垩纪热河生物群分布特征及地层对比研究,明确了内蒙古热河生物群分布区域、产出层位、组合差异及古气候和古环境演变规律,进一步理清了内蒙古地区白垩纪沉积古地理、古气候和古环境演变与热河生物群辐射演化的制约和协同关系. 相似文献
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15.
四合屯地区位于一个中生代火山一沉积盆地之中。该区早白垩世的主要构造行迹为NE向和NW向的断裂构造;这些断裂构造控制着火山一沉积盆地的边界和一些火山机构的分布。野外填图表明,该盆地内的早白垩世地层仅出露有义县组。义县组可进一步划分为3个段：第1段为含有沉凝灰岩夹层的基性、中基性火山岩;第2段是含有凝灰岩夹层和枕状熔岩的陆相沉积岩;第3段主要为玄武岩类。热河生物群(其中包括腹足类、双壳类、叶肢介、介形类、昆虫、鱼类、两栖类、爬行类、鸟类、哺乳类以及植物)化石主要产于义县组一段沉凝灰岩和二段的湖相泥质页岩中。化石发掘和微量元素分析表明,热河生物群经历了集群死亡和快速掩埋,火山活动的有毒气体是生物灾难事件的主要因素。根据同位素测年,义县组的时代为早白垩世。在此基础上,本文讨论了四合屯地区早白垩世构造一火山活动与生物事件的演化阶段：A阶段为盆地雏形的产生和早期的热河生物群;B阶段为第一次火山活动和生物灾难事件;C阶段为火山活动间歇期和热河生物群的繁衍;D阶段为火山喷汽与热河生物群的灾难事件;E阶段为火山灰沉降;F阶段为结束期。 相似文献
16.
Prophaenognatha robusta gen. et sp. nov. (Scarabaeoidea: Scarabaeidae: Aclopinae), the best-preserved aclopine fossil so far, is described and illustrated from the Upper Jurassic–Lower Cretaceous Yixian Formation of the Jehol Biota, western Liaoning Province, NE China. The key to extinct and extant genera of Aclopinae is given and the monophyly of extant and fossil Aclopinae lineages is supported by five character states. The new taxon provides evidence about the evolution of Scarabaeoidea with its phylogenetic position inferred based on 68 morphological characters. 相似文献
17.
四合屯及其周边地区义县组火山活动对生物灾难事件的影响 总被引：5，自引：0，他引：5
野外填图证实 ,四合屯及其周边地区热河生物群化石主要产于义县组下部的沉凝灰岩和中部的内陆湖泊相沉积岩之中。综合研究还发现 ,上述化石层之中发育有火山弹、湖泊相枕状熔岩以及数层火山碎屑和火山灰物质 ;在产有珍稀鸟类、爬行类以及早期被子植物化石的岩石中 ,As,Hg ,S的含量明显高于相关的对比层。种种迹象表明 ,四合屯及其周边地区的义县组火山活动所产生的熔岩流和有毒、有害气体以及频繁爆发的火山灰等是造成热河生物群灾难事件并使其得以保存的主要因素 相似文献
18.
三尾拟蜉蝣在中国热河生物群可能并不存在 总被引：2，自引：0，他引：2
热河生物群是中生代晚期分布在东亚地区尤其是中国辽西、冀北地区的一个非常繁荣的陆相化石群,东方叶肢介（Eosestheria）、“三尾拟蜉蝣（Ephemeropsis trisetalis）”和狼鳍鱼（Lycoptera）是它的3个典型代表成员。最近对采自义县组的上百块与三尾拟蜉蝣较为相似的成虫标本研究,发现上述成虫标本与三尾拟蜉蝣存在比较明显的区别,建立了美丽蜉蝣属及其两个种,并认为三尾拟蜉蝣可能仅分布在俄罗斯西伯利亚的外贝加尔和蒙古,在中国热河生物群并不存在。这一发现对有关热河生物群的古地理分布、地层划分和对比以及古水系等问题有重要的参考意义。 相似文献