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1.
Non-marine Jurassic rocks are widespread in the northeastern part (Khorat Plateau), and partly in the northern, eastern, and southern parts of Thailand. In the Khorat Plateau, the rocks, more than 1000 m thick, are represented by the Phu Kradung and Phra Wihan Formations of the Khorat Group but are less extensive in the north, east, and south. Reddish brown to grayish purple sandstones, siltstones, claystones, conglomeratic sandstones and conglomerates are the main lithologies; calcrete nodules are also present in claystones only in the Phu Kradung Formation. Deposition occurred mostly in meandering and braided rivers in semi-arid and slightly humid conditions for the Phu Kradung and Phra Wihan Formations, respectively, except for the southern rocks, where lacustrine deposits dominate. Age determinations are based mainly on vertebrates, bivalves and palynomorphs indicating reassignment to the Jurassicpossibly Early Cretaceous. 相似文献
2.
In China, the marine Jurassic is mainly distributed in the Qinghai-Tibetan Plateau, southwestern China and environs including southwestern Xinjiang and western Yunnan. Along the western palaeo-Pacific coast, marine Jurassic deposits, which usually intercalate with nonmarine strata, exist sporadically in eastern Heilongjiang, western Fujian, Hongkong, central Guangdong, western Jiangxi, eastern and southwestern Hunan Province, and probably also in western Taiwan. Nonmarine Jurassic strata are widely distributed in the whole of China except for southern Tibet area. They are commonly intercalated with volcanic rocks and contain volcanic materials in eastern China, and in southern Tibet. Marine strata yield various abundant fossils including ammonites, which were widespread in the Tethyan Realm even all over the world. Consequently, China is a critical region to attempt marine and non-marine Jurassic correlation. Through various investigations, both marine and non-marine Jurassic biozonations or assemblages have been established and by this the marine and non-marine Jurassic stratigraphic system and their correlation in China have been clarified. 相似文献
3.
In China, the marine Jurassic is mainly distributed in the Qinghai-Tibetan Plateau, southwestern China and environs including southwestern Xinjiang and western Yunnan. Along the western palaeo-Pacific coast, marine Jurassic deposits, which usually intercalate with nonmarine strata, exist sporadically in eastern Heilongjiang, western Fujian, Hongkong, central Guangdong, western Jiangxi, eastern and southwestern Hunan Province, and probably also in western Taiwan. Nonmarine Jurassic strata are widely distributed in the whole of China except for southern Tibet area. They are commonly intercalated with volcanic rocks and contain volcanic materials in eastern China, and in southern Tibet. Marine strata yield various abundant fossils including ammonites, which were widespread in the Tethyan Realm even all over the world. Consequently, China is a critical region to attempt marine and non-marine Jurassic correlation. Through various investigations, both marine and non-marine Jurassic biozonations or assemblages have been established and by this the marine and non-marine Jurassic stratigraphic system and their correlation in China have been clarified. 相似文献
4.
Thai marine Jurassic rocks are well exposed in the Mae Sot, Umphang, and Phop Phra areas, less extensively near Mae Hong Son, Kanchanaburi, Chumphon, Nakhon Si Thammarat and Krabi. Generally they rest unconformably on Permian and Triassic, and are overlain by Quaternary strata. Fourteen lithostratigraphic units are defined (in ascending order): Pa Lan, Mai Hung, Kong Mu formations of the Huai Pong Group-Mae Hong Son area; Khun Huai, Doi Yot, Pha De formations of the Hua Fai Group-Mae Sot area; Klo Tho, Ta Sue Kho, Pu Khloe Khi, Lu Kloc Tu formations of the Umphang Group-Umphang area; and Khlong Min Formation-Chumphon, Nakhon Si Thammarat, and Krabi areas. Dominant widespread mudstones, siltstones and sandstones; limestones are confined to the Mae Sot, Phob Phra, Umphang, Kanchanaburi and Mae Hong Son areas; marls are found only in Mae Sot. Sequences are approximately 900 m thick (Mae Sot), 450 m thick (Umphang) and thinner elsewhere, especially the south. Based on ammonites, brackish to marine bivalves, and foraminifera, the beds are dated mainly as ToarcianEarly Bajocian. 相似文献
5.
MEESOOK Assanee SHA Jingeng SAENGSRICHAN Wirote TEERARUNGSIGUL Naramase 《自然科学进展(英文版)》2006,16(13):119-152
Thai marine Jurassic rocks are well exposed in the Mae Sot, Umphang, and Phop Phra areas, less extensively near Mae Hong Son, Kanchanaburi, Chumphon, Nakhon Si Thammarat and Krabi. Generally they rest unconformably on Permian and Triassic, and are overlain by Quaternary strata. Fourteen lithostratigraphic units are defined (in ascending order): Pa Lan, Mai Hung, Kong Mu formations of the Huai Pong Group-Mae Hong Son area; Khun Huai, Doi Yot, Pha De formations of the Hua Fai Group-Mae Sot area; Klo Tho, Ta Sue Kho, Pu Khloe Khi, Lu Kloc Tu formations of the Umphang Group-Umphang area; and Khlong Min Formation-Chumphon, Nakhon Si Thammarat, and Krabi areas. Dominant widespread mudstones, siltstones and sandstones; limestones are confined to the Mae Sot, Phob Phra, Umphang, Kanchanaburi and Mae Hong Son areas; marls are found only in Mae Sot. Sequences are approximately 900 m thick (Mae Sot), 450 m thick (Umphang) and thinner elsewhere, especially the south. Based on ammonites, brackish to marine bivalves, and foraminifera, the beds are dated mainly as ToarcianEarly Bajocian. 相似文献
6.
Volcanic tuff deposits near Daohugou village, Ningcheng County of Inner Mongolia have yielded many wellpreserved fossils. Here we briefly introduce our recent findings of invertebrates from the Daohugou fauna: mainly insects, conchostracans, anostracans, and spiders. The age of the Daohugou fauna is considered to be Middle Jurassic on the basis of an analysis of various invertebrates especially insects and conchostracans, showing strong similarities to the Yanliao fauna of north China and the Karatau fauna of Kazakhstan. 相似文献
7.
Volcanic tuff deposits near Daohugou village, Ningcheng County of Inner Mongolia have yielded many wellpreserved fossils. Here we briefly introduce our recent findings of invertebrates from the Daohugou fauna: mainly insects, conchostracans, anostracans, and spiders. The age of the Daohugou fauna is considered to be Middle Jurassic on the basis of an analysis of various invertebrates especially insects and conchostracans, showing strong similarities to the Yanliao fauna of north China and the Karatau fauna of Kazakhstan. 相似文献
8.
针对海外含油气盆地勘探程度较低、资料相对匮乏的问题,以呵呖高原盆地为例开展了成藏组合及油气资源潜力研究,研究中以构造沉积演化成藏的递进控制作用为核心,获得了以下认识。晚古生代新生代,盆地构造演化可划分为两期构造层序TS1和TS2;其中,TS1构造层序内主要充填浅海相滨岸、陆棚、碳酸盐岩台地沉积,TS2构造层序内主要充填陆相冲积扇、河流、湖泊沉积;沉积相控制下盆地内发育两套主要的生储盖组合,结合盆地的主要圈闭类型,进一步划分出已证实二叠系和远景三叠系两个一级成藏组合,4套二级成藏组合;在下一阶段的勘探中,纵向上应侧重于二叠系一级成藏组合的天然气勘探,平面上应重视以Phu Phan隆起为主的盆地中部及以Khorat次盆北部和Sakhon Nakhon次盆西部为主的盆地西部地区,前者发育二叠系一级成藏组合最有利油气勘探区,后者为三叠系一级成藏组合最有利油气勘探区。 相似文献
9.
苟宗海 《成都理工大学学报(自然科学版)》2003,30(2):147-154
西藏聂拉木县聂聂雄拉地区，早、中侏罗世地层较发育，地层中化石属 种繁多。地层划分为下侏罗统“普普嘎组”，中侏罗统聂聂雄拉组和拉弄拉组。作者研究了该区旱、中侏罗世的双壳类动物群40多属80多种。描述双壳类化石8新种：Tancredia(T.)nyalamensis,Hiatellasubtrigona,Pronoella(P.)minima,Opis(O.)curvus,Costigeruillia tetracostata,Weyla costalliformisa,Entolium obliquus,E.subfilosus,刊出部分化石图版，简述双壳类化石组合特征。它的研究对该地区旱、中侏罗世地层划分对比，生物地理分区和动物群特征的认识都具有一定的理论与实践意义。 相似文献
10.
百花山兽类区系特征及生态分布 总被引：4，自引：0，他引：4
１９８９～１９９１年对百花山自然保护区的兽类区系进行了比较系统的调查，共记录到６目１３科２５种．整个区系以古北界成分为主，占６８．０％，同时也呈现出比较明显的南、北两方动物分布的过渡特征．本文从地理分布特征出发，对本区兽类区系的组成进行了比较详细的分析，并讨论了这些兽类的生态分布和垂直分布状况以及鼠形动物的季节变化． 相似文献
11.
The studies of uplift and glaciations of the Tibetan Plateau are summarized, and a series of recent case studies of the endemic species based on DNA sequences are detailed. In general, these molecular data show that all the organisms originated from Early Pliocene to Late Miocene, and then multi-stages of divergence/speciation occurred within each taxa following their original occupation on the plateau, mainly as a result of periodic glacial cycles and geographic isolation. The regional fauna may have undergone several range contractions and expansions during the Pleistocene glaciations. However, the population expansion and refugia may vary in space, time, and extent. The regional fauna of the Tibetan Plateau may be combinations of ancient movement from adjacent zoogeographical regions,speciation in situ, and postglacial colonization from adjacent areas. Geomorphic and climatic changes on the plateau definitely have a remarkable influence on the regional and adjacent biogeographic patterns, and the mechanism is very complex. 相似文献
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13.
张永普 《杭州师范学院学报(自然科学版)》1999,(3)
作者于１９９１～１９９５年对温州地区的淡水蛭类进行了调查研究,所得标本经鉴定共计淡水蛭类２１种,隶属于１３属、７科;经分析其区系属于中国－日本区,其中３种为我国特有种 相似文献
14.
张永普 《杭州师范学院学报(社会科学版)》1999,(3)
作者于１９９１～１９９５年对温州地区的淡水蛭类进行了调查研究,所得标本经鉴定共计淡水蛭类２１种,隶属于１３属、７科;经分析其区系属于中国－日本区,其中３种为我国特有种． 相似文献
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16.
本文研讨了岷江上游彻底关至映秀湾河段的水生无脊椎动物区系与生物量,分析了该河段中受引水式工程影响而出现的水库化与脱水河段,及与之相关的环境、水生无脊椎动物区系与生物量动态。 相似文献
17.
采用昆虫分类学原理和方法，调查研究辽宁省丽蝇科昆虫的种数、分布及区系特征；在辽宁省发现丽蝇科昆虫41种，隶属于3亚科17属，并记述了辽宁省该科分类概况、名录及分布，讨论了辽宁省丽蝇科昆虫的区系分布特点；辽宁省丽蝇科种数占全国已知种数的17．67％，属总数的34．69％． 相似文献
18.
Nicol MORTON 《自然科学进展(英文版)》2006,16(13):1-11
The historical development of the chronostratigraphic classification of the Jurassic into series, stages and zones is summarised. Traditionally, the series and stages are defined hierarchically in terms of the standard (ammonite) zones they contained but since Hedberg (1976)［1］ they have been defined by a basal boundary stratotype (GSSP). To date four Jurassic Stages have ratified GSSPs; progress with the others is outlined. The primary marker for the definition of the Stage boundaries is biochronology based on evolution of ammonites, with secondary markers based on biostratigraphy of other fossil groups, chemostratigraphy and magnetostratigraphy. Causal mechanisms for the environmental changes that caused ammonite evolution are reviewed and possible methods of correlation with nonmarine successions are briefly discussed. 相似文献
19.
Lü Houyuan 《科学通报(英文版)》2003,48(5):411-416
The study of natural vegetation of geological and historical periods in the Loess Plateau is an important scientific and practical issue for the development of northwestern China.However,interpretation of the natural vegetation before human reclamation is still controversial.The paper aims to analyze the potentical factors that cause the difference in knowledge of Holocene natural vegetation developing in different topographies of the Loess Plateau.The distribution of paleovegetation in this region shows significant difference among rocky mountains,valleys,and Yuan lands(the plain area),i.e.it does not follow the natural vegetation zonation,as that in eastern China does.The Yuan lands with thick loess accumulation were never covered by a vast of dense forests during the Holocene.Forests (or open forests)developed preferably in valleys in the southern part of the Plateau and rocky mountains on the Plateau during the warm period of the Holocene.Some of local vegetation outside of the Loess Plateau are more subjected to the control of geomorphology and ground water. 相似文献
20.
笔者对虎伯寮国家级自然保护区进行五年的考察,共采得蝶类10科111属208种。对其中已知种名的203种蝶类进行区系分析表明,虎伯寮保护区蝶类在动物地理区划中应归属于东洋界、华南区,它们明显具有热带北缘及亚热带区系色彩,其中印澳区蝶类在北进扩展中,存在着由热带向亚热带过渡的区系性质。 相似文献