Terminal Precambrian Palaeogeographic Framework of China

The original locations and relationships of four plates within the mainland of China from 800 to 600 Ma during the terminal Precambrian were reconstructed based on the palaeomagnetic and geological data. The Tarim, Yangtze and Cathaysian plates were once linked (in 800-700 Ma) and located in the same low-latitude zone of the northern hemisphere. But later, in 700-600 Ma, the Tarim plate was separated from the Yangtze-Cathaysian plate. The Sino-Korean plate was always far away from the Yangtze plate, both being separated by oceanic crust, and lay in the high-latitude zone of the northern hemisphere.The above-mentioned palaeogeographic framework directly led to complete differences in respect to distribution of low-latitude glaciation, sedimentary facies, palaeoclimate, palaeobiogeography and stratigraphic sections between the North and South China domains during the terminal Precambrian.

Palaeogeographic Position of the South China Plate During the Early-Middle Devonian

In Guangxi, the Lower-Middle Devonian boundary beds yield abundant corals, brachiopods,stromatoporoids and conodonts. The former three were common in tropical and subtropical zones, while thelast occurred only round the equator. This reveals that the South China Plate in the Early-Middle Devonianwas at or near the equator, which was also supported by palaeomagnetic study giving the palaeolatitude of theGuangxi Region at the time to be 0°36′N.

Sequence-stratigraphic frameworks and their palaeogeographic patterns for the Permian Lopingian of the Dianqiangui Basin and its adjacent areas of Southwestern China

The Permian Lopingian in the Dianqiangui Basin and its adjacent areas is marked by the coal measures of the Wuchiapingian and the carbonate strata of the Changhsingian stages. For the Lopingian of the Dianqiangui Basin and its adjacent areas,the diversity of sedimentary facies and the obviousness of facies change provide an advantaged condition on a study of sequence stratigraphy. Approximately,the Wuchiapingian stage constitutes a third-order sequence and the Changhsingian stage forms an-other. For the Wuchiapingian stage in the study area,coal-measures were developed on the attached platform and,in addition,a special coal-measure that is composed of both limestone beds and coal beds was also developed in the central part of some isolated platforms. Grain-bank grainstones and packstones were formed on the margin of the attached platform as well as in the windward part of iso-lated platforms. For the Changhsingian stage in the study area,open-platform limestones were formed on the attached platform,while sponge-reef limestones were developed both on the margin of the at-tached platform and on the isolated platforms. The Lopingian Series is a set of basin-facies muddy shales with interbeds of silicalites in the inter-platform basin,which appears a set of the large-thick coarse clastic strata of molasses covering direct the deep-water strata from the Devonian to the Per-mian Yangsingian in the Qinzhou-Fangcheng region in the southern part of the study area. All of these features indicate the complexity of temporal-spatial facies-changes. Sequence-stratigraphic frame-works could be established,which would illustrate two types of facies-changing surfaces and dia-chronisms in the stratigraphic records,based on the combination of both biostratigraphic and chronostratigraphic materials and the regularity reflected by temporal evolutionary succession of sediments as well as spatial distributional patterns of sedimentary facies. Ultimately,features of sedi-mentary succession and palaeogeographical evolution of the Permian Lopingian in the study area are revealed clearly in a series of the panel diagrams of sequence-stratigraphic frameworks and the outline maps showing the sedimentary-facies and palaeogeography. The Permian Lopingian formed by two third-order sequences differs from the stratigraphy of the same era characterized by the constant re-gression along Euramerica. Most specially,if the end-Guadalupian mass-extinction event is genetically related to a regressive event represented by the unconformity of the first episode of the Dongwumovement in the study area,the mass-extinction event at the turn from the Permian to the Triassic is genetically related to a rapid transgressive event re-flected by the drowning unconformity in the study area. These phenomena might reveal a complex rela-tionship between mass-extinction events and trans-gressive-regressive events.

On palaeogeographic map

The palaeogeographic map is a graphic representation of physical geographical character- istics in geological history periods and human history periods. It is the most important result of palaeogeographic study. The author, as the Editor-in-Chief oflournal of Palaeogeography, Chinese Edition and English Edition, aimed at the problems of the articles submitted to and published in the]ournal of Palaeogeography in recent years and the relevant papers and books of others, and integrated with his practice of palaeogeographic study and mapping, wrote this paper. The content mainly includes the data of palaeogeographic mapping, the prob- lems of palaeogeographic mapping method, the ＂Single factor analysis and multifactor comprehensive mapping method ---- Methodology of quantitative lithofacies palae- ogeography＇, i.e., the ＂4 steps mapping method＂, the nomenclature of each palaeogeographic unit in palaeogeographic map, the explanation of each palaeogeographic unit in palae- ogeographic map, the explanation of significance of palaeogeographic map and palae- ogeographic article, the evaluative standards of palaeogeographic map and palaeogeographic article, and the self-evaluation. Criticisms and corrections are welcome. 2016 China University of Petroleum {Beijing）. Production and hosting by Elsevier B.V. on behalf of China University of Petroleum （Beijing）. This is an open access article under

Devonian Sea-Level Change Rhythms in South China and Coupling Relationships Among the Earth-spheres

Twenty orthosequences and their corresponding sea-level change (SLC) cycles have been recognized in the Devonian overlying the Caledonian unconformity, of which 9, 5.5 and 5.5 occurred in the Lower, Middle and Upper Devonian respectively. They can be grouped into 4 orthosequence sets, in which the maximum flooding surfaces lie in the sulcutus Zone (D12), perbonus Zone (D13), Middle and Upper varcus Zone (D22) and gigas Zone (D21) respectively. Four instant palaeogeographical reconstructions of South China have been made in the Emsian and Givetian. Devonian sea-level change rhythms of South China can be divided into 3 categories: the autorhythmic, the worldwide and regional allorhythmic, and the coupling-rhythmic. They developed respectively in the Famennian, Pragian, Eifelian, Lochkovian, Emsian, Givetian, Frasnian and the F / F (between the Frasnian and Famennian) event. The cause of the worldwide allorhythmic SLC of the Pragian and Eifelian under comparatively dry, warm and tranquil conditions may be related to the pulsating expanding and contracting of the oceanic basin volume or the earth volume pulsation, rather than the common glaciation and plate tectonism. The coupling-rhythmic SLC related to the F/ F event is a sensitive indicator of the interaction between terrestrial and extraterrestrial factors, and coordinated action among the earth-spheres.

Silurian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than100 years.With the launch of the Second Tibetan Plateau Scientific Expedition and Research,it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding areas.In this study,we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas,summarised the available data in terms of stratigraphic regionalisation,lithostratigraphy,chronostratigraphy,and biostratigraphy,and divided the study area into four stratigraphic provinces:the Xizang-Western Yunnan-Western Sichuan Province,the KunlunQilian Province,the South China Province,and the Tarim Province.In general,the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of China.Palaeobiogeographical studies of the vertebrate faunas,sporomorph assemblages,and brachiopod faunas of the study area indicate a closer geographical relationship between the South China,Tarim,and Indochina palaeoplates,than previously considered.Compared with the surrounding areas where Silurian strata have been extensively studied,the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary stage.In the future,it is necessary to conduct research on the age,distribution,and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in China.The shallow marine strata of the middle to upper Silurian require further subdivision.Considering that the Silurian System in the Qinghai-Tibetan Plateau is more complete,it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

Palaeogeography of China

Palaeogeography is a science that studies the features and evolution of physical geography in geological history and human history. The palaeogeography of China has multiple disciplines and multiple types of palaeogeographic map. These perfectly reflect 'a hundred flowers blossom and a hundred schools of thought content'. The palaeogeography of China has three characteristics. The first is multiple disciplines flourishing simultaneously. The second is that lithofacies palaeogeography is in a leading position. The third is that palaeogeography of China is closely connected with industrial practice. It is why palaeogeography, especially lithofacies palaeogeography of China, can flourish continually. We have two journals of palaeogeography, i. e. Journal of Palaeogeography (Chinese Edition) and Journal of Palaeogeography (English Edition). The former primarily publishes articles of Chinese authors regarding Chinese palaeogeography and related disciplines and has a foothold in China. The latter will publish the articles of both Chinese and international authors and caters to foreign readers. These two journals will cooperate together and display their own expertise, which will effectively make a great contribution to the development and innovation of Chinese palaeogeography and international palaeogeography.