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Mainland China has the most complex continental tectonics on Earth, making it one of the ideal laboratories for probing the tectonics and evolution of the Earth. However, no consensus has been reached regarding the basement tectonic architectures and evolution of mainland China. This paper focuses on the interpretation of aeromagnetic and seismic refraction data, closely incorporating available surface geological data, borehole data, and seismic data to trace the likely occurrences of oceanic plateau slices in the basement architecture of mainland China. We suggest that the highly positive aeromagnetic anomalies and thick high-velocity lower crustal layer indicate that the Junggar basin is floored by an oceanic plateau. The Tarim basin can be divided into a southeastern oceanic plateau block with strongly positive aeromagnetic anomalies and a northwestern passive continental margin block with weak aeromagnetic anomalies. Both blocks got amalgamated together during the late Paleoproterozoic, and the irregular, promiscuous aeromagnetic anomalies within the northwestern block are spatially consistent with and attributed genetically to the Tarim Large Igneous Province (LIP). The lower crust of the Qaidam basin is characterized by large P-wave velocity, suggesting that the basin is floored by an Early Paleozoic oceanic plateau, and the deep-seated subduction of the oceanic plateau could be responsible for the ultrahigh-pressure (UHP) metamorphism in the northern Qaidam margin during the Early Paleozoic. The western North China craton could be an assembly of multiple oceanic plateau fragments along irregular continental margins during the Paleoproterozoic. An intraplate suture (Miaowan suture) divides the Yangtze craton kernel to the east and the Shennong terrane to the west; both were amalgamated during the Neoproterozoic. The Yangtze craton kernel could be floored by an oceanic plateau basement characterized by large P-wave velocity and strongly positive aeromagnetic anomalies. All these oceanic plateau basements exhibit strong rigidity to resist later tectonic deformation and generally remain intact. • Junggar basin is floored by oceanic plateau of highly positive magnetic anomalies 3 and high velocity • Tarim basin is divided into northeastern oceanic plateau and southwestern passive 5 margin. • Qaidam basin is floored by oceanic plateau, whose subduction resulted in UHPM 7 in N. Qaidam margin • Western North China craton is an assembly of oceanic plateaus during the 9 Paleoproterozoic • Yangtze craton kernel is floored by oceanic plateau and divided by Miaowan suture 11 from Shennong terrane. [ABSTRACT FROM AUTHOR]

The Korean Peninsula (KP) occupies a junction area of three big tectonic domains that are the Paleo-Central Asian Orogenic Belt, Paleo-Tethyan Orogenic Belt and the Western Pacific Orogenic Belt. Therefore the KP is a key area to understand the Northeast Asian and even global geotectonic evolution. In terms of geological unit division, the KP has long been thought to be closely tied with the mainland of China, with using collective term the Sino-Korea Craton for the North China Craton (NCC). However, such correlation suffered from the absence of relevant geological information in North Korea (NK). To bridge this knowledge gap, our group carries out a long-term collaborative study between the two-sides of the KP and China，and organized united field investigation in the North Korea, South Korea (SK) and China as possible. This paper introduces general geology in the North Korea，and simply make comparison with the NCC and South Korea. These pioneering works culminated in the following summaries. (1) The KP comprises three major Precambrian massifs, i.e., Rangnim, Gyeonggi and Yeongnam massifs. The Rangnim and Gyeonggi massifs are separated by the Imjingang Structural Belt, while the Gyeonggi and Yeongnam massifs are separated by the Ogcheon Structural Belt. (2) The basement of the Rangnim massif is correlated with that of the NCC. The characteristic metamorphic rocks of high- temperature/high-pressure granulite facies including meta- sedimentary rocks (kondalites and meta-sandstones and marbles) with ~1.9–1.8 Ga metamorphic ages occur in the three massifs, similar to the NCC. (3) The Proterozoic rift sedimentary sequences are developed in the NCC and North Korea, but Lower Paleoproterozoic strata are rare, and Neoproterozoic strata are more developed in North Korea relative to the NCC. (4) Two main Paleozoic basins within the Rangnim massif and within the Gyeonggi and Yeongnam massifs are the Phyongnam basin and Taebaeksan Basin. Both of them have a similar Paleozoic tectono-stratigraphy to the NCC. (5) Although the nature and tectonic significance of the Imjingang belt remains controversial, it doesn't show characteristics and natures of collisional orogenic belt. (6) The eclogite-bearing Hongseong Complex (HSC) is located in the southwestern part of the Gyeonggi Massif in South Korea, but no similar rock unit has been found in North Korea. (7) Mesozoic igneous rocks are widespread throughout the northern and southern parts of the KP. Triassic magmatism is related to Indosinian orogeny. Jurassic and Cretaceous igneous rocks are different and irregular from those in the NCC on age and spatial-temporal distribution. This paper also suggests several key and controversial academic issues that are worthwhile to study in the future. Unlabelled Image • The Archean Rangrim massif is divideded into the Rangrim and Kwanmo submassifs, high-grade region and greenstone belt, respectively. • Early Paleoproterozoic rocks underwent metamorphism up to granulite facies, which may be correlated to the Jiao-Liao-Ji mobile belt in the NCC. • Proterozoic rift sequences in North Korea are similar to those in the NCC with rare late Paleoproterozoic strata and more Neoproterozoic strata. • Both main Paleozoic basins, the Phyongnam basin in NK and the Taebaeksan Basin in SK, have a similar Paleozoic tectono-stratigraphy to the NCC. • Mesozoic igneous rocks are extensively distributed in the KP. [ABSTRACT FROM AUTHOR]

The Proterozoic geological records in eastern South China preserve a history linked to the Columbia and Rodinia supercontinent cycles and provide key constraints in understanding the geodynamic evolution of East Asia. However, it is uncertain if SW Hainan, Yangtze and Cathaysia were located in the interior or periphery of the Precambrian supercontinents, how they were connected prior to the formation of a united South China, whether the early Neoproterozoic Proto-Huanan subduction was long- or short-lived, and how and when Yangtze and Cathaysia were assembled along the Jiangnan Orogen. This paper provides an overview of key geological observations for the eastern Yangtze and Cathaysia with respect to Proterozoic tectonics. Our synthesis shows that the SW Hainan in the Mesoproterozoic (ca. 1.45 Ga) developed in a non-orogenic rift setting in the interior of Columbia. SW Hainan, together with SW Yangtze, drifted to the margin of Rodinia by ∼1.05 Ga. Furthermore, SW Hainan might have been part of the Mesoproterozoic Albany Fraser Orogen at ca. 1.30–1.05 Ga. Cathaysia and eastern Yangtze display distinct geological signatures in the early Neoproterozoic and Cathaysia remain separated from Yangtze until at least ca. 1.0 Ga. The ca. 1.0–0.9 Ga felsic igneous rocks in Cathaysia to the east of the Jiangshan-Shaoxing suture zone are mostly characterized by negative ε Hf (t) values, and distinct from those in the coeval Shuangxiwu arc to the west of the Jiangshan-Shaoxing suture zone, which have positive ε Hf (t) values. Igneous rocks dated at ca. 870–830 Ma (mainly ca. 850–830 Ma) are extensive in the Huaiyu and Jiangnan Orogen but poorly developed in Cathaysia. Neoproterozoic sedimentary rocks of Cathaysia contain abundant ca. 980 Ma detrital grains but only minor ca. 860–830 Ma grains. In contrast, in the Jiangnan and Huaiyu, the sedimentary rocks contain a dominant ca. 860–830 Ma detrital zircon age-peak but ca. 980 Ma grains are scare. Rift-related bi-model igneous rocks, ranging in age from ca. 810 Ma to ca. 750 Ma, represented by the Banxi, Likou and Mamianshan groups and their equivalents, are extensively developed in Cathaysia and Huaiyu, and the Jiangnan Orogen. These rift-related successions are separated from the Cangshuipu and Luojiamen conglomerates across an angular unconformity, which are in turn unconformable on the Lengjiaxi and Xikou groups. It is herein proposed that an early Neoproterozoic (ca. 1.0–0.9 Ga) accretionary orogen developed within the Cathaysia and lay along strike from the synchronous Eastern Ghats Orogen of India. A long-lived Neoproterozoic (ca. 0.97–0.83 Ga) Proto-Huanan arc-trench system resulted in the development of the ca. 0.98–0.88 Ga Shuangxiwu intra-oceanic arc, ca. 0.87–0.83 Huaiyu continental arc and ca. 0.87–0.83 Jiangnan intra-continental back- arc basin in response to the ongoing westward-subduction beneath the eastern Yangtze. At ca. 0.87 Ga, the arc-trench system switched from an intra-oceanic to a continental Andean margin setting. Such a system might be compatible to the NW India South Delhi Orogen at the periphery of Rodinia. Our synthesis shows that the united proto-South China was finally created by the ca. 830–810 Ma assemblage of the Yangtze with Cathaysia along the Jiangnan Orogen and was followed by the post-orogenic rifting due to the breakup of Rodinia. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) was generated through multiple collisional and accretionary events in the Paleo-Asian Ocean, a major global ocean that existed from the late Neoproterozoic into the late Paleozoic. Nevertheless, the question of when the Paleo-Asian Ocean finally closed has notoriously been enigmatic, especially due to the absence of large-scale investigations. The South Tianshan-Solonker Suture, is the largest and southernmost suture within the CAOB, and records the ultimate collision between the Tarim-North China cratons with the Siberia craton, and is commonly interpreted as marking the eventual closure of the Paleo-Asian Ocean. In this paper, we synthesize and evaluate relevant Chinese papers on the area, which are not readily available to an international audience, and extend this across the full length of the suture zone. Based on this review, we can divide the suture zone into four distinct segments, which are, from west to east: the South Tianshan Belt, the Beishan Belt, the Solonker Belt and the Yanji Belt. This enables us to provide a more systematic understanding of the nature and development of the South Tianshan-Solonker suture. Geochronological data from Paleozoic cover rocks and high-pressure metamorphic rocks show that during the late Carboniferous, the western section of the Paleo-Asian Ocean closed when the Tarim Craton moved northward to collide with the Kazakhstan-Yili Block, thus marking the initial development of the South Tianshan Belt. The Beishan Belt to the east formed when the Dunhuang-Alxa blocks were transported northward to collide with the Tuva-Mongolia Block, with the youngest zircon U Pb data from ophiolites indicating that closure of the local Beishan Ocean was in the early-middle Permian, although its final closure may not have been until the early late Permian along the northern margin of the Alxa Block, thus making it slightly younger than the South Tianshan Belt. Further to the east, the available petrographic, geochronological and paleontological data from the Solonker Belt indicate that this belt was formed in the middle-late Permian, during which time bi-directional subduction occurred and the North China and Siberia cratons were amalgamated during an 'Appalachian-type' orogeny. Furthermore, we observe that a transition in polarity from northward to bi-directional subduction occurred along the boundary between the Beishan and Solonker belts, which may be related to the East Gobi Transform Fault. In contrast, under the influence of the westward subduction of the Paleo-Pacific Ocean, the Jiamusi-Khanka Block moved southwestward along the Yilan-Yitong Fault in the middle-late Triassic (230–220 Ma) to amalgamate with the North China Craton. The formation of the South Tianshan-Solonker Suture can be characterized by four distinct west-to-east accretion/collision events that lasted from the late Carboniferous to the late Permian. The South Tianshan Belt, the Beishan Belt and the Solonker Belt therefore demarcate, respectively, the amalgamation between the Tarim Craton and the Kazakhstan-Yili Block, the Dunhuang-Alxa Block and the Tuva-Mongolia Block, and the North China Craton with the Siberia Craton, representing the final closure of the Paleo-Asian Ocean. During the middle-late Triassic, the Yanji Belt in the far east was influenced by the Paleo-Pacific tectonic domain as a result of amalgamation between the Jiamusi-Khanka Block and the North China Craton. • South Tianshan-Solonker Suture marks the final collision between Tarim-North China and Siberian cratons. • The Suture includes four segments, and closed form Late Carboniferous to Middle Triassic from west to east, respectively. • The Yanji belt was influenced by the Paleo-Pacific tectonic domain during the Middle Triassic. [ABSTRACT FROM AUTHOR]

Abstract: The paper takes China's authoritative Environmental Impact Statement for the Yangzi (Yangtze) Three Gorges Project (TGP) in 1992 as a benchmark against which to evaluate emerging major environmental outcomes since the initial impoundment of the Three Gorges reservoir in 2003. The paper particularly examines five crucial environmental aspects and associated causal factors. The five domains include human resettlement and the carrying capacity of local environments (especially land), water quality, reservoir sedimentation and downstream riverbed erosion, soil erosion, and seismic activity and geological hazards. Lessons from the environmental impact assessments of the TGP are: (1) hydro project planning needs to take place at a broader scale, and a strategic environmental assessment at a broader scale is necessary in advance of individual environmental impact assessments; (2) national policy and planning adjustments need to react quickly to the impact changes of large projects; (3) long-term environmental monitoring systems and joint operations with other large projects in the upstream areas of a river basin should be established, and the cross-impacts of climate change on projects and possible impacts of projects on regional or local climate considered. [Copyright &y& Elsevier]

Abstract: Arid and semiarid China have experienced multiple arid phases throughout the Quaternary, and over the past five decades, there have been several periods with relatively high or low rates of desertification and rehabilitation. The causes of these changes and their historical trends have been debated by scientists because of their potentially huge significance for China, as well as for the global ecology and food supply. This paper reviews recent studies of desertification in different regions of arid and semiarid China. In general, the results of systematic monitoring, and analyses of the causes of desertification and the contemporaneous human impacts, suggest that desertification in China has been primarily caused by climate change, and particularly by strong wind regimes (with high sand transport potential) accompanied by decreased spring precipitation. Unfortunately, although numerous scientists have claimed that desertification in China is primarily due to human impacts; there is surprisingly little unassailable evidence to support this claim. The review presented in this paper show that desertification in China is likely to be controlled by climate change and geomorphological processes, even though human impacts have undeniably exacerbated their effects. Our arguments for both climate change and human activity as factors responsible for the observed changes in desertification rely primarily on inferences based on correlations between trends, thus future research must seek stronger and more direct evidence for the causal relationships that we have proposed as possibilities. This improved information is essential to provide a firm basis for future policy decisions on how best to combat desertification. [Copyright &y& Elsevier]

China is a key area for research into human occupation in the Old World after the initial expansion of early humans out of Africa. Reliable age determinations are pivotal for assessing the patterns of human evolution and dispersal in this region. This paper reviews magnetostratigraphic studies of some early Pleistocene strata bearing hominin remains and/or artifact stone tools from northern to southern China. The quality and reliability of the paleomagnetic dates are also evaluated. New magnetostratigraphic results for the Xihoudu Paleolithic site in north-central China are also presented.Among the few hominin or Paleolithic sites in China from the early Pleistocene, five have been well investigated. Three of these are in northern China at Xiaochangliang, Donggutuo and Gongwangling; the remaining two in southern China at Longgupo and Yuanmou. Considerable progress has been made during the past three decades towards paleomagnetically dating these sites. Indeed, the age estimates at Xiaochangliang and Gongwangling have been widely accepted. Magnetostratigraphic consensus about the age of the Donggutuo site has also been reached. However, the age determination for the two sites in southern China is still contested.The integration of rock-magnetic stratigraphy with magnetic polarity stratigraphy has resulted in a determined age of 1.36 Ma for a stone tool-containing layer of lacustrine sediments at the Xiaochangliang site in the Nihewan Basin. Lithostratigraphic constraints have significantly contributed to determining the age of Lantian Homo erectus at Gongwangling, which occurred in a loess–paleosol sequence of the southern Loess Plateau. Its age, paleomagnetically derived, is about 1.15 Ma. These two paleomagnetic ages suggest an expansion and flourishing of human groups from northern to north-central China during the early Pleistocene. This suggestion has been reinforced by our new magnetostratigraphic age estimate of about 1.27 Ma for the Xihoudu site as will be presented in this paper. However, more work is needed for the age determinations of the hominin-bearing strata at the Longgupo and Yuanmou sites in southern China. Finally, we stress that it is necessary to combine biostratigraphy, lithostratigraphy and rock-magnetic stratigraphy with the traditional magnetic polarity stratigraphy in order to obtain reliable age determinations for strata bearing hominin remains or stone artifacts. [Copyright &y& Elsevier]

Despite the enormous potential of continental shale oil resources, only recoverable shale oil is economically valuable. Shale oil development decisions can greatly benefit from an accurate assessment of recoverable shale oil resources. Three crucial factors for evaluating shale oil recoverable resources are shale oil content, movable oil ratio, and recovery factor. However, because of the significant variety of continental shale, it is challenging to define the aforementioned characteristics. The methodologies and technology for determining the shale oil recoverable resource evaluation parameters, particularly the shale oil content, movable oil ratio, and recovery factor, are thoroughly discussed in this paper. Taking the Tertiary Sha-3 continental shale in Dongpu and Nanpu sags in Bohai Bay Basin, eastern China as an example, the shale oil content was obtained by the pyrolysis method with light and heavy hydrocarbon calibration comprehensively considered, and the main controlling factors of shale oil content were explored. Four geological parameters, including the sedimentary facies, pore structure, surrounding rock quality, and burial depth, primarily regulate the variation features of continental shale oil. The formation mechanism and primary governing variables of movable oil were then revealed using a physical simulation experiment. As porosity and permeability rise, clay mineral content falls, oil viscosity falls, and kerogen concentration rises, the movable oil ratio rises as well. Through stepwise linear regression, a quantitative estimation model for movable oil ratio was developed. After that, a literature search was used to determine the average recovery factor for continental shale oil. Finally, using the volume method model and the Monte Carlo methodology, the recoverable shale oil resources in the Gaoliu area of Nanpu Sag were assessed. The retention, movability, and resource potential of continental shale oil are better understood as a result of this study. [ABSTRACT FROM AUTHOR]

China is the country with the most population in the world, and its climate is extremely diverse due to tremendous differences in latitude, longitude, and altitude, ranging from tropical in the far south to subarctic in the far north and alpine in the higher elevations of the Qinghai-Tibetan Plateau. Accurate assessment of its modern climate change is conductive to addressing global warming threat. Along with the development of Past Global Changes (PAGES) research, the focus has changed from paleo-climate reconstructions to using paleo-data for assessing the present and predicting the future. Previous studies have been devoted to climate change assessment using modern climate observations and simulations. This paper presents a new assessment approach based on the mid-Holocene, which provides a naturally oriented warming that can be compared to modern human-made global warming. A variety of climatic data, including modern observations, paleo-climate records, CMIP5 (Coupled Model Intercomparison Project Phase 5) and PMIP3 (Paleoclimate Modelling Intercomparison Project 3) simulations, as well as lake level models, were applied in this synthesis. Numerical climate classification was introduced to evaluate climate change impacts to Chinese climate zones on various time scales. The results show that winter and summer seasons have different response to the naturally oriented mid-Holocene warming but human-made global warming makes the warming trend appear in all seasons. Temperate and continental dry winter climates expand dramatically during the mid-Holocene warm period; however, the future global warming could have few impacts to Chinese climate zones. Furthermore, the East Asian summer monsoon was strengthened obviously by the mid-Holocene warm climate and strong low-latitude insolation. There is no consistent trend both for the winter and summer monsoon on the background of human-made global warming. In this study, a new benchmark was established based on paleo-climate to evaluate the impacts of human-made global warming. [ABSTRACT FROM AUTHOR]

This paper summarizes available lithostratigraphic, tectonothermal, geochronological and geophysical data to investigate the formation and evolution of the Yinshan Block, the tectonic nature of the Ordos Block, and the subduction to collision history of the Khondalite Belt, and establishes Paleoproterozoic accretion and assembly of the Western Block of the North China Craton. New critical evidence indicates that a magmatic arc developed in the Ordos Block caused by the initiation of northward slab subduction beneath the southern margin of the Ordos Block during 2.3–2.0 Ga, which contributed to the opening of the back-arc basin between the Ordos and Yinshan blocks. And then, the north margin of the Ordos Block was then transformed into a passive-type continental margin and collided with the Yinshan Block along the Khondalite Belt to form the Western Block after final closure of the back-arc basin during 1.97–1.91 Ga. Seismic data across the Western Block including a 300-km-long south-north-trending receiver function profile and a common conversion point stacking image in depth domain obviously show its crustal structure, in which the relics of two subduction slabs were preserved beneath the Ordos Block and the Khondalite Belt, respectively. Therefore, we propose a new tectonic model to help to better constrain Paleoproterozoic accretion and assembly of the Western Block in North China. [ABSTRACT FROM AUTHOR]

The early Precambrian tectonic framework and evolution of the North China Craton (NCC) remain diversely contentious. This paper presents an overview mainly of the progresses in metamorphic studies for the NNCC and proposes alternative litho-tectonic division and tectonic scenarios for the Paleoproterozoic NNCC based on the recognized four phases of metamorphism. Five litho-tectonic units can be divided in the NNCC, including the Yinshan Block (YB), Wulashan Reworked Belt (WRB), Jining Mobile Belt (JMB), Huai'an Reworked Belt (HRB) and the Longgang Block (LB). All of them underwent different metamorphic modification during the Orosirian period at 1.98–1.80 Ga. The Orosirian metamorphism in the NNCC includes four phases. The first-phase metamorphism (M-I) occurred at >1.95 Ga, is the medium- P/T type marked by high-pressure (HP) granulites. It shows clockwise P–T paths characterized by the pre- P max (peak pressure) prograde and post- P max decompression, indicating a crustal thickening orogeny. The second-phase metamorphism (M-II) occurred during 1.94–1.90 Ga, is the low- P/T type marked by ultrahigh-temperature (UHT) granulites. It shares clockwise P–T paths characterized by the pre- T max (peak temperature) decompression-heating from HP granulite conditions and post- T max isobaric cooling. This UHT metamorphism may ascribe to conductive and advective heating from mantle upwelling and hyperthermal mafic magma intraplating in a post-orogenic setting with back-arc extension. The third-phase metamorphism (M-III) is the high- P/T type characteristic of eclogites occurred at >1.88 Ga, which, together with ∼1.90 Ga ophiolitic mélanges, suggests oceanic subduction beneath the northern margin of the NCC. The fourth-phase metamorphism (M-IV) is also the medium- P/T type with clockwise P–T paths, occurred during 1.88–1.82 Ga. It is represented by the Barrovian metamorphic zones in the east WRB, staurolite-overprints in the north HRB, metabasic dykes up to HP granulite facies in the north LB, and HP granulites in the south YB, registering another collisional orogeny in the NNCC. Based on these four phases of Orosirian metamorphism, and combined with other geological data in the NNCC, we present an alternative tectonic model which involves the following tectonic scenarios: (i) The Siderian–Rhyacian (2.46–2.00 Ga) extension occurred in back-arc or within-plate settings, resulted in the YB separated from LB, and the Paleoproterozoic volcano-sedimentary sequences, granite intrusions and basic dykes formed in the WRB, JMB, HRB. (ii) The early Orosirian (2.00–1.95 Ga) crust thickening orogeny occurred on account of the collision between the NCC and an unknown continent, as indicated by M-I metamorphism, which gave rise to an orogen trended mainly in north-east between the YB and LB, nominated as the west North China Orogen (WNCO). (iii) The mid-Orosirian (1.95–1.88 Ga) oceanic subduction and back-arc extension occurred as suggested by M-II and M-III metamorphism. And (iv) the late Orosirian (1.88–1.82 Ga) collisional orogeny resulted from a collision between the NCC and the south Siberian Craton, which gave rise to an orogen trended in east–west, named the north North China Orogen (NNCO). [ABSTRACT FROM AUTHOR]

Northeast (NE) China is located in the eastern Central Asian Orogenic Belt (CAOB) and evolved from the amalgamation of several microcontinental blocks, which, from west to east, include the Erguna, Xing'an, Songliao, and Jiamusi-Khanka blocks. Since the Paleozoic, NE China has undergone multiple stages of subduction–accretion and tectonic destruction under the tectonic domains of the Paleo-Asian Ocean, Panthalassa, and the Paleo-Pacific Ocean. This complexity has resulted in uncertainty surrounding the amalgamation processes of the various microcontinents. Fortunately, several suture zones in NE China, including the Toudaoqiao–Xinlin Suture, the Hegenshan–Heihe Suture, the Solonker–Xar Moron–Changchun Suture, and the Jilin–Heilongjiang High-pressure Belt contain information that provides key constraints on the tectonic evolution of NE China. This paper reviews the spatial distribution, composition, and formation ages of these suture zones based on published geological records. Our temporal and spatial analyses of these suture zones enable the evolution of NE China to be assigned to those three tectonic domains: (1) In the earliest of these, the Paleo-Asian Ocean tectonic domain (650–250 Ma), the Erguna Block amalgamated with the Xing'an Block along the Toudaoqiao–Xinlin Suture during the Late Cambrian (ca. 500 Ma); the Erguna–Xing'an Block then collided with the Songliao Block along the Hegenshan–Heihe Suture during the Late Carboniferous (ca. 300 Ma), whilst the combined Erguna–Xing'an–Songliao Block amalgamated with the North China Craton along the Solonker–Xar Moron–Changchun Suture at the End-Permian (ca. 250 Ma). (2) in the Panthalassa tectonic domain (315–230 Ma), the subduction of Panthalassa (or locally, the Mongol-Okhotsk Ocean) was initiated in the eastern Jiamusi-Khanka Block during the Late Carboniferous (ca. 315 Ma), resulting in back-arc extension in the western Jiamusi-Khanka Block, which evolved into the Heilongjiang Ocean separating the Jiamusi-Khanka and Songliao blocks during the Late Permian to Late Triassic (260–230 Ma). (3) in the Paleo-Pacific Ocean tectonic domain (230–130 Ma), the first stage of westward subduction of the Paleo-Pacific oceanic plate occurred during the Late Triassic (ca. 230 Ma), causing the Jiamusi-Khanka Block to amalgamate with the North China Craton during the Late Triassic (ca. 230 Ma) and subsequently with the Songliao Block during the Late Triassic to Early Jurassic (210–180 Ma), forming the Jilin–Heilongjiang High-pressure Belt, whereas the second stage of subduction induced the emplacement of the Nadanhada Terrane during the Early Cretaceous (ca. 130 Ma). This represented the final assembly of NE China in the eastern CAOB. • NE China can be divided into three tectonic domains of the Paleo-Asian Ocean, the Panthalassa, and the Paleo-Pacific Ocean. • The assembly of NE China was accomplished through the generation of five suture zones, which formed from ∼500 Ma to ∼130 Ma. • NE China recorded multiple stages of activity of the Paleo-Asian, Panthalassa (Mongol-Okhotsk), and the Paleo-Pacific oceans. [ABSTRACT FROM AUTHOR]

Subduction and closure of the Proto-Tethys and Palaeo-Tethys oceans were important events in the assembly of Eurasia, and created the Central China Orogenic Belt (CCOB). This paper presents a new tectonic model for the CCOB in which we propose that elongate Precambrian basement blocks within the CCOB were originally part of a single ribbon continent, here named K-Qubed after the K unlun- Q aidam- Q ilian- Q inling regions. K-Qubed separated from the South China Block in the Neoproterozoic. Dextral-oblique subduction of the Proto-Tethys Ocean took place southwards (present co-ordinates) under K-Qubed in latest Precambrian - Cambrian times (ca. 550–500 Ma). Subduction-accretion complexes were generated alongside the basement, while arc magmatism overprinted both basement and accretionary crust. Initial collision of the northern side of the ribbon continent and the North China and Tarim blocks occurred at ca. 500 Ma. High-pressure and ultrahigh-pressure metamorphism resulted by ca. 490 Ma, in the North Qilian, South Altun/North Qaidam and North Qinling regions. Collision triggered a flip in subduction polarity, and caused a subduction-accretion complex and magmatic arc to build out southwards from K-Qubed, as Palaeo-Tethys was consumed northwards in the Ordovician. Magmatic timings were similar between different tectonic units; twin peaks in magmatism at ca. 500–490 Ma and ca. 440–430 Ma occurred in several terranes. Oblique subduction caused strain partitioning, in turn causing slivering and across-strike repetition of basement and accretionary crust. Tectonic units in the Qilian Shan and Kunlun can be partly correlated with equivalents in the Qinling Orogen. We suggest a match between the North Qilian Orogenic Belt and the Erlangping Unit, between the Central Qilian Block and the North Qinling Belt, between the South Qilian Accretionary Belt and the Shangdan Suture Zone. Basement terranes of the Qaidam region and the East Kunlun Orogen have no obvious lateral equivalents in the Qinling, and are truncated at the eastern margins by the West Qinling Belt. There are similar ages for peak metamorphism at ca. 440–420 Ma in an eclogite belt in the North Qaidam Ultra High-pressure Metamorphic Belt (NQUB) and eclogite localities in the East Kunlun Orogen. We interpret this metamorphism to be result of slab break-off beneath the K-Qubed continent, with metamorphic rocks repeated across-strike by dextral shear. The component of Precambrian crust in the Kunlun diminishes westwards into the West Kunlun, where Early Palaeozoic accretion of crust was more continuous. A magmatic gap throughout the CCOB between ca. 370 and ca. 290 Ma was possibly related to extremely oblique and/or slow plate convergence, or represents a time through which subduction stopped. Renewed northwards subduction of the Palaeo-Tethyan Ocean took place under the south side of the Kunlun and Qinling in the Permian, completed by Triassic collisions of the Qiangtang and South China blocks with the southern side of the CCOB. This model for the CCOB is an alternative to collisional and accretionary end members for orogeny, whereby oblique subduction and collision of a ribbon continent produces interleaving of basement and more juvenile terranes. Closure of Proto-Tethys did not involve multiple, separate and synchronous subduction zones, or repetition of a subduction zone by oroclinal bending, as previously proposed. [ABSTRACT FROM AUTHOR]

There is a strong inter-annual and inter-decadal variability in time series of variables related to water abundance, such as intense precipitation, high river discharge, flood magnitude, and flood loss in China. Part of this variability can be random or chaotic, but it may well be that climate variability track plays an important role in the interpretation of the variability of water abundance. The principal aim of this review paper is to create a summary of literature-based information on links of various climate-variability drivers, i.e. natural oscillations in the ocean–atmosphere system, and the variability of characteristics of destructive water abundance in China, at a range of spatial scales (national, provincial, basin-based, municipal). The present paper reviews extensive pool of literature discussing the links between the two modes of oscillation in the ocean-atmosphere system (ENSO - El Niño -Southern Oscillation and PDO – Pacific Decadal Oscillation) and variability in time series of variables related to water abundance in China. This paper also reviews examples of extension of the database, with the help of proxies. It reviews interpretation of possible link of particular large flood events (e.g. the 1998 and the 2016 deluges) to climate variability. Also a range of issues of relevance to water management are reviewed, such as seasonal forecasting and non-stationarity of flood frequency. [ABSTRACT FROM AUTHOR]

Lithospheric subduction prior to the assembly of the South China and North China blocks is traditionally considered to be directed northward. However, some critical geological and geochemical data cannot be reconciled with this northward subduction. This paper presents new lines of evidence against the traditional models and proposes a new and revolutionary tectonic model to explain the distribution and exhumation of high pressure (HP)-ultrahigh pressure (UHP) metamorphic rocks of the Dabie-Sulu Belt. We emphasize the following: 1) The Triassic tectonic environment of the southern margin of the North China Block was passive, not active, based on the stratigraphy; 2) In the southern margin of the North China Block no arc magmatism was recorded. 3) Many Paleoproterozoic slices of Jiaobei affinity of the Jiao-Liao-Ji Belt in the North China Block were located in the Triassic Sulu Orogen. 4) Many 1.85 Ga metamorphic zircons are preserved in the Dabie-Sulu high pressure-ultra-high pressure (HP-UHP) metamorphic rocks. 5) The geometric asymmetry of many structural patterns in the HP-UHP slices indicates top-to-the northwest thrusting during the exhumation of HP-UHP slices. 6) Blueschists occur in the south of the UHP eclogite slices. 7) In the eastern segment of the North Qinling Orogen, no components with an affinity of the South China Block have been found. Along the Shangdan Suture of the Qinling Orogen has been recorded an apparent northward subduction. We consider that the suture is just a lateral subduction zone rather than a major collisional zone. Along the Shangdan Suture, the rarity of I-type plutonism can be attributed to a transform-type continental margin. The Bureya-Jiamusi-Khanka Block has an affinity to the South China Block based on its similarity regarding the Paleozoic history of deformation and Triassic blueschist metamorphic facies metamorphism. The Bureya-Jiamusi-Khanka Block could be the northern extension of the Dabie-Sulu Belt, and this gigantic belt could be interpreted as an orocline related to the southeastward subduction of the North China Block beneath the Greater South China Block. [ABSTRACT FROM AUTHOR]

In their thoughtful paper entitled "An equable subtropical climate throughout China in the Miocene based on palaeofloral evidence", Qing Wang, Yan Li, David K. Ferguson, Wen-Bo Mo, and Nan Yang (2021) imply that China exhibited negligible latitudinal mean annual precipitation (MAP) gradients and lacked arid regions during the Miocene. They also speculate that there was no abrupt change in elevation of the Tibetan Plateau, nor that the plateau attained its present altitude or orography during that period. These conclusions were derived mainly by using a co-existence approach (CA) and 'incomplete data'. Here, we use CA with training data and also integrate a coexistence likelihood estimation, a pollen-MAP boundary, a desert-MAP boundary, and other newly published MAP data to show that Northwest China consistently exhibited drier conditions than South China and East China during the entire Miocene, with our new values being 300–500 mm lower than those of Wang et al. (2021). This implies that there were large spatial gradients of MAP in China during the Miocene, which may be directly linked with the growth of the Tibetan Plateau, the global cooling, as well as other factors. We recommend the comprehensive consideration of multiple methods and proxies for reconstructing past climate conditions as opposed to a single proxy. [ABSTRACT FROM AUTHOR]

The Meishan section, South China is the Global Stratotype Section and Point (GSSP) for the Permian–Triassic boundary (PTB), and is also well known for the best record demonstrating the Permian–Triassic mass extinction (PTME) all over the world. This section has also been studied using multidisciplinary approaches to reveal the possible causes for the greatest Phanerozoic biocrisis of life on Earth; many important scenarios interpreting the great dying have been proposed on the basis of data from Meishan. Nevertheless, debates on biotic extinction patterns and possible killers still continue. This paper reviews all fossil and sedimentary records from the Permo-Triassic (P–Tr) transition, based on previously published data and our newly obtained data from Meishan, and assesses ecologically the PTME and its aftermath to determine the biotic response to climatic and environmental extremes associated with the biocrisis. Eight updated conodont zones: Clarkina yini , Clarkina meishanensis , Hindeodus changxingensis , Clarkina taylorae , Hindeodus parvus , Isarcicella staeschei , Isarcicella isarcica , and Clarkina planata zones are proposed for the PTB beds at Meishan. Major turnover in fossil fragment contents and ichnodiversity occurs across the boundary between Bed 24e-5 and Bed 24e-6, suggesting an extinction horizon in a thin stratigraphic interval. The irregular surface in the middle of Bed 27 is re-interpreted as a firmground of Glossifungites ichnofacies rather than the previously proposed submarine dissolution surface or hardground surface. Both fossil fragment contents and ichnodiversity underwent dramatic declines in Beds 25–26a, coinciding with metazoan mass extinction. Fossil fragment content, ichnodiversity and all ichnofabric proxies (including burrow size, tiering level, bioturbation level) indicate that the P–Tr ecologic crisis comprises two discrete stages, coinciding with the first and second phases of the PTME in Meishan. Ecologic crisis lagged behind biodiversity decline during the PTME. Pyrite framboid size variations suggest that depositional redox condition was anoxic to euxinic in the latest Changhsingian, became euxinic in Beds 25–26a, turned dysoxic in Bed 27, then varied from euxinic to anoxic through most of the Griesbachian. The ~ 9 °C increase in seawater surface temperature from Bed 24e to Bed 27 at Meishan seems to result in dramatic declines in biodiversity and fossil fragment contents in Beds 25–26a, but had little effect on all ecologic proxies. Both metazoans and infauna seem not to have been affected by the pre-extinction anoxic–euxinic condition. The anoxic event associated with the PTME may have occurred in a much shorter period than previously thought and is only recorded in Beds 25–26a at Meishan. Fossil fragment contents, ichnofaunas, ichnofabrics and pyrite framboid size all show that no signs of oceanic acidification and anoxia existed in Bed 27. The early Griesbachian anoxia may have resulted in rarity of ichnofauna and metazoans in the lower Yinkeng Formation, in which the ichnofauna is characterized by small, simple horizontal burrows of Planolites , and metazoan faunas are characterized by low diversity, high abundance, opportunist-dominated communities. The rapid increase of ~ 9 °C in sea-surface temperature and a short anoxia or acidification coincided with the first-pulse biocrisis, while a prolonged and widespread anoxia probably due to a long period of high seawater temperate condition may be crucial in mortality of most organisms in the second-pulse PTME. Marine ecosystems started to recover, coupled with environmental amelioration, in the late Griesbachian. [ABSTRACT FROM AUTHOR]

The distribution patterns of rare earth elements (REEs) are frequently used as proxies for ancient seawater chemistry or paleomarine environmental conditions. However, recent work has shown that diagenesis can lead to remobilization and inter-elemental fractionation of REEs, and that these effects often occur in conjunction with redox reactions in sediment porewaters. Here, we review existing literature on the diagenetic fluxes of REEs in marine sediments and porewaters in order to systematize existing knowledge on this subject. REEs undergo significant redistribution among sediment phases during both early and late diagenesis as a consequence of adsorption and desorption processes. Remobilization of REEs commonly leads to inter-elemental fractionation, variously leading to enrichment or depletion of the light, middle, or heavy REE fractions. Further, REE remobilization can be facilitated by redox changes, e.g., through reductive dissolution of host phases in suboxic and anoxic porewaters. Characteristic REE distribution patterns develop through these processes: (1) a ‘flat distribution’ signifying predominantly terrigenous siliciclastic influence, (2) a ‘middle-REE bulge’ probably due to adsorption of light and heavy REEs to Mn- and Fe-oxyhydroxides, respectively, and (3) ‘heavy-REE enrichment’ indicative of hydrogenous (seawater) influence (note: all patterns in this paper are normalized to the REE composition of average upper continental crust, or UCC). In the second part of this study, we undertake an analysis of the REE distributions in conodonts and whole-rock samples from West Pingdingshan, a Permian–Triassic boundary section in South China. Using ΣREE/Th and Y/Ho ratios, we show that almost all of the conodont samples have a strong diagenetic overprint, and that the hydrogenous REE fraction is small and not isolatable. Furthermore, the conodonts contain two diagenetic REE components, one characterized by low ΣREE (100–300 ppm), high ΣREE/Th ratios (> 1000), strong middle REE enrichment, and Eu/Eu* ratios of ~ 1.5–2.0, and the second by high ΣREE (300–2000 ppm), low ΣREE/Th ratios (~ 20–30), little or no middle REE enrichment, and Eu/Eu* ratios of ~ 1.0. The first component exhibits a pronounced middle-REE bulge that represents an early diagenetic signature associated with suboxic conditions, possibly related to adsorption of REEs onto Fe–Mn oxyhydroxides in the shallow subsurface environment. The second component shows a flat REE distribution that is similar to both our whole-rock samples and average UCC, indicating derivation from REEs released from detrital siliciclastics (e.g., clay minerals), probably at a range of burial depths from shallow to deep. Failure of the conodont samples to yield an isolatable hydrogenous component demonstrates that bioapatite does not always preserve a primary marine REE signature. Given that bioapatite REEs have been widely used for this purpose, often on the assumption of minimal or no diagenetic influence, our findings are likely to necessitate a re-evaluation of the results of many earlier studies. In general, we counsel caution in inferring a hydrogenous origin for REEs in bioapatite owing to frequent diagenetic alteration of REE distributions. [ABSTRACT FROM AUTHOR]

In comparison with the amount of study undertaken on the end-Permian mass extinction, the preceding Guadalupian mass extinction has received little investigation, even though it marks a significant biotic turnover associated with global environmental changes. During the earlier event, reef carbonate production shut down and was replaced by siliceous, mud-rich deposits (SRDs) in South China. However, changes in carbonate platform productivity during this epoch remain to be clarified. This paper presents sedimentological and conodont biostratigraphic investigations on the Guadalupian SRDs developed on the Yangtze Carbonate Platform (YCP) in central Guizhou. The findings are viewed in the context of Guadalupian sequence correlation of South China successions, which shows that the integrity of the YCP failed to match the platform tectonic evolution. The platform evolution saw the onset of major intra-platform depressions and the gradual onlap by SRDs along the platform margin. Stratigraphic correlation reveals that the platform experienced three phases of onlap by SRDs during the early Roadian, the late Wordian and the late Capitanian upwards. Platform carbonates re-expanded their extent following the first two phases, but not during the final phase. An evolutionary model is proposed for the Guadalupian carbonate platform, which follows the contemporaneous eustatic sea-level fluctuations. The partial drowning observed within the platform interior and increasing retreat along the platform margin could suggest an insufficient carbonate sediment supply shedding from the platform top during the Guadalupian. The variation in carbonate productivity raises our attention to the change in shallow-water carbonate factories, which is closely related to the fortunes of carbonate-secreting biota and environmental factors impacting the carbonate platform producers during the Guadalupian. [ABSTRACT FROM AUTHOR]

A recent paper (Deng et al., 2017) reported detrital zircon geochronology from sandy sediments of the Lanyang River and the Zhuoshui River in the east and west Taiwan, respectively. They demonstrated that zircons from the Yangtze Block and the North China Block could be transported to the proto-Taiwan region by paleo-longshore currents. However, it is here suggested that, detrital zircons are unlikely to be transported over such long distances by paleo-longshore currents. Furthermore, the Min River in the Cathaysia Block might be a potential, and more accessible, primary provenance. The contribution of Min River to Taiwan sediments should be taken into account. [ABSTRACT FROM AUTHOR]

Abstract: The Cretaceous tectonic evolution of South China is characterized by widespread extensional basin and dome generation, voluminous magma intrusion/eruption and associated polymetallic mineralization, all of which are of world-wide interests that have stimulated the attention of geologists for more than half a century. Due to the lack of a comprehensive understanding of regional tectonic evolution and geodynamics of South China, many controversies regarding the nature and origin of these features remain. This paper attempts to make a review by synthesizing existing structural, petrological, geochronological and geochemical data of the Cretaceous structures and magmas, which guides us to propose a three-stage tectono-thermal evolutionary history of South China during the Cretaceous period. The earliest Cretaceous (145–137Ma) tectonic stage was characterized by syn-orogenic shortening deformation and metamorphism under a NW–SE compressional setting, which generated voluminous porphyry Cu–Au ore-bearing adakitic rocks in the Lower Yangtze River Belt and gneissic granites in the coastal area. Its geodynamic origin was interpreted as combined effects of the Pacific–Izanagi ridge subduction beneath the Lower Yangtze River Belt and the Pacific subduction beneath the Cathaysia Block. This syn-orogenic shortening stage was followed by a post orogenic stage (136–86Ma) comprising two episodes of alternate extensional and shortening events. The extension (136–118Ma) in the earlier episode was dominated by a NW–SE extensional regime, it led to significant taphrogenesis manifested by large-scale extensional basins and voluminous magma intrusion/eruption; this extensional event was associated with a combination of the slab window opening during the ridge subduction and the rollback of the subducted Pacific slab. The subsequent NW–SE transpressional event led to cessation of active marginal magmatism and resulted in tectonic inversion of previous rift basins; this transpression lasted from 117Ma to 108Ma, and its driving mechanism was attributed to the collision between the eastern Asian margin and the West Philippine Block. The extension (107–86Ma) in the later episode was dominated by a WNW–ESE extensional regime, which led to a second phase of basin subsidence and produced numerous A- and I-type granites and bimodal volcanoes. The tectonic regime then changed at ca. 85Ma to WNW–ESE-oriented transpression, causing inversion of the Late Cretaceous rift basins and cessation of extension-related magmatism. The change of stress field from WNW–ESE extension to WNW–ESE transpression was related to the variations of the subducted slab dynamics, i.e., the transition from either the ESE-ward retreat to WNW-ward subduction of the Pacific slab, or the alternate stress during slab break-off. During the latest Cretaceous, a drastic change of regional tectonic stress orientation from WNW–ESE to N–S occurred in South China, the third stage predominated by N–S extension was developed, which caused a new phase of regional crustal subsidence along the youngest E–W trending extensional structures. [Copyright &y& Elsevier]

Sedimentary basins in China are globally special for retaining large volumes of carbon dioxide. To date, over 40 CO 2 gas fields (>60 vol% CO 2) and many more CO 2 -rich hydrocarbon fields (15–60 vol% CO 2) have been discovered across China. Valuable knowledge of CO 2 migration, accumulation, and long-term sequestration processes in sedimentary basins can be acquired by analysing various CO 2 fields in China. This paper reviews three key aspects of CO 2 reservoirs in Chinese sedimentary basins: (1) CO 2 origin, (2) factors controlling the distribution of CO 2 gas, and (3) the long-term effect of CO 2 emplacement on reservoir rocks. Both the eastern and western parts of China have several giant sedimentary basins. CO 2 -rich gases are predominantly discovered in eastern China among rift basins, with sandstone, carbonate, and volcanic rocks being the principal reservoirs. Analyses of carbon and helium isotopes suggest that the high abundance of CO 2 in eastern China is primarily of mantle origin, with subordinate crustal CO 2. Igneous intrusives and faults control the migration and accumulation of CO 2 -rich gases within the basins. The offshore Yinggehai Basin, however, is an exception in eastern China, where the majority of CO 2 appears to be of crustal origin, resulting from thermolysis of carbonate minerals. For this type of CO 2 , mud diapirs in the deep basin, which serve as upward passages for geothermal fluids, control the distribution of CO 2 -rich gases. In comparison, sedimentary basins in western China generally contain minor amounts of CO 2 (< 5 vol%) in the produced gases. The low-concentration CO 2 is mostly of crustal origin, from the decomposition of organic matter and carbonate minerals or, in a few places, from the thermochemical sulphate reduction process. Pore fluids in CO 2 reservoirs of China are characterised by high salinity, owing to elevated concentrations of Na+ and HCO- 3 induced by CO 2 emplacement. Pervasive dissolutions of feldspars are widely observed in sandstone and volcanic reservoirs in China, and dawsonite is the most common authigenic mineral. Dawsonite growth did not cause significant variations in the reservoir porosity in most cases. Mantle-derived CO 2 has been suggested to promote kerogen maturation and oil migration in sedimentary basins, thereby helping to form some oilfields in China. [ABSTRACT FROM AUTHOR]

East Asia is exceptionally rich in diverse geological phenomena related to processes of major global significance in Earth history. Its tectonic evolution is closely related to the subduction of the Izanagi and Pacific plates and the India-Eurasia collision. Thus, this domain presents a vast natural laboratory within which some of the most topical and fundamental problems in Pacific-Asian Tectonics can be addressed. Recent breakthroughs in understanding the tectonic evolution of East Asia have been achieved, involving intraplate deformation, plate fragmentation, plate boundary processes, orogenic collapse, and craton destruction. These advances have been achieved via multidisciplinary work including structural geology, basin research, land and marine geophysics, thermochronology, numerical modeling, geochemistry and classical field geology. In the current context of research in East Asia the time is ripe for a thematic volume of review papers. This special issue is focused on the theme "Pacific-Asian Tectonics". It describes interdisciplinary methods adopted to study Meso-Cenozoic basin-forming mechanisms and evolutionary processes, unravels the timing and characteristics of major intraplate deformation, depicts the spatial-temporal distribution of Meso-Cenozoic igneous rocks, discusses the deep lithospheric structures overlying the subducting oceanic plates, and probes the natures and fates of subduction or collision processes. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, published data for granulite terrain rocks exposed at the surface, lower crustal xenoliths, and Mesozoic intermediate-felsic igneous rocks from the eastern North China craton (NCC) are integrated to constrain the nature and evolution of the lower crust in this area. U–Pb zircon dating shows that the protolith ages for most of the granulite terrain rocks are 2500 to 2600Ma and that many of them experienced 1800–1900Ma metamorphism. Lower crustal xenoliths entrained in volcanic rocks with ages varying from ~460 to ~10Ma suggest that the lower crust is dominated by Neoarchean rocks, although there may be minor rocks with ages of Meso- to Paleoarchean (>3000Ma), ~45Ma and possibly ~1900Ma locally. The Mesozoic intrusive rocks, although varying from diorite to granite and spanning from Triassic to Cretaceous, contain ~2500Ma inherited zircons and have magmatic zircons with Hf crust model ages (TDM Hf, C) ages of 2500–2700Ma and whole-rock Sr–Nd isotopic compositions falling within the field of the granulite terrain rocks, pointing to their derivation by the melting of Neoarchean lower crust. The combined data for the granulite terrain rocks, lower crustal xenoliths and Mesozoic intermediate-felsic igneous rocks indicate that the present lower crust is dominated by rocks with Neoarchean ages and is intermediate to mafic in composition (i.e., SiO2 <62%). The (87Sr/86Sr)i, εNd (t) and εHf (t) of the lower crust at 130Ma are considered to be 0.705 to 0.716, −10 to −28 and −13 to −28, respectively. The εNd (t) range is very different from that proposed previously (−32 to −44). The large range of εHf (t) for the lower crust implies that significant εHf (t) variations for magmatic zircons from the Mesozoic intermediate-felsic igneous rocks do not necessarily reflect mixing of mantle– and crustal–magmas as commonly thought, instead they may reflect heterogeneity in the ancient lower crust. Given that the voluminous Mesozoic intermediate to felsic igneous rocks in the eastern NCC are derived dominantly by partial melting of the Archean lower crust, it requires that a large amount of Archean lower crust be restitic. A restite origin can explain some of the Hannuoba granulite xenoliths having higher Mg# than the granulite terrains. It may be applicable to other parts of the world. [Copyright &y& Elsevier]

Abstract: China's Badain Jaran Sand Sea features the tallest dunes on Earth and a unique mega-dune–lake landscape. It had been explored little until the 1990s, though early scientific explorations surrounding the sand sea had begun by the early 20th century. Heated debates now focus on the desert environment, and particularly how the mega-dunes and desert lakes develop and evolve. This paper reviews the status of these debates and summarizes the supporting evidences. The environmental research mainly concerns formation and evolution of the sand sea, and its relationship with climate change. The proposed formation time ranges from the Early Pleistocene to the Holocene. Opinions vary about climate change on different time scales. The reconstructed climate change history is shorter than the sand sea's history, with the longest record extending to the Late Pleistocene. The mega-dune research focuses on sediments, dune morphology, and formation processes. It remains unclear whether the mega-dunes result primarily from wind action, control by the underlying topography, or groundwater maintenance. The sources of lake water are also debated, but there are four main hypotheses: atmospheric precipitation, groundwater from nearby areas, precipitation and snowmelt in remote areas such as the Qilian Mountains and the Qinghai–Tibetan Plateau, or paleowater that formed during past periods of wet climate. We believe that the sand sea deserves further study in terms of its dune geomorphology, evolution, and hydrology, and their responses to climate change. Meteorological and hydrological observations and monitoring in the sand sea are particularly necessary. [Copyright &y& Elsevier]

Abstract: In areas of high relief, many glaciers have extensive covers of supraglacial debris in their ablation zones, which alters both rates and spatial patterns of melting, with important consequences for glacier response to climate change. Wastage of debris-covered glaciers can be associated with the formation of large moraine-dammed lakes, posing risk of glacier lake outburst floods (GLOFs). In this paper, we use observations of glaciers in the Mount Everest region to present an integrated view of debris-covered glacier response to climate change, which helps provide a long-term perspective on evolving GLOF risks. In recent decades, debris-covered glaciers in the Everest region have been losing mass at a mean rate of ~0.32myr−1, although in most cases there has been little or no change in terminus position. Mass loss occurs by 4 main processes: (1) melting of clean ice close to glacier ELAs; (2) melting beneath surface debris; (3) melting of ice cliffs and calving around the margins of supraglacial ponds; and (4) calving into deep proglacial lakes. Modelling of processes (1) and (2) shows that Everest-region glaciers typically have an inverted ablation gradient in their lower reaches, due to the effects of a down-glacier increase in debris thickness. Mass loss is therefore focused in the mid parts of glacier ablation zones, causing localised surface lowering and a reduction in downglacier surface gradient, which in turn reduce driving stress and glacier velocity, so the lower ablation zones of many glaciers are now stagnant. Model results also indicate that increased summer temperatures have raised the altitude of the rain–snow transition during the summer monsoon period, reducing snow accumulation and ice flux to lower elevations. As downwasting proceeds, formerly efficient supraglacial and englacial drainage networks are broken up, and supraglacial lakes form in hollows on the glacier surface. Ablation rates around supraglacial lakes are typically one or two orders of magnitude greater than sub-debris melt rates, so extensive lake formation accelerates overall rates of ice loss. Most supraglacial lakes are ‘perched’ above hydrological base level, and are susceptible to drainage if they become connected to the englacial drainage system. Speleological surveys of conduits show that large englacial voids can be created by drainage of warm lake waters along pre-existing weaknesses in the ice. Roof collapses can open these voids up to the surface, and commonly provide the nuclei of new lakes. Thus, by influencing both lake drainage and formation, englacial conduits exert a strong control on surface ablation rates. An important threshold is crossed when downwasting glacier surfaces intersect the hydrological base level of the glacier. Base-level lakes formed behind intact moraine dams can grow monotonically, and in some cases can pose serious GLOF hazards. Glacier termini can evolve in different ways in response to the same climatic forcing, so that potentially hazardous lakes will form in some situations but not others. Additionally, the probability of a flood is not simply a function of lake volume, but depends on the geometry and structure of the dam, and possible trigger mechanisms such as ice- or rockfalls into the lake. Satellite-based measurements of glacier surface gradient and ice velocities allow probable future locations of base-level lakes to be identified. A base-level lake has begun to grow rapidly on Ngozumpa Glacier west of Mount Everest, and could attain a volume of ~108 m3 within the next 2 or 3 decades. Unless mitigation efforts are undertaken, this lake could pose considerable GLOF hazard potential. [Copyright &y& Elsevier]

Abstract: China''s Lop Nur is one of the world''s largest playas, and is located in the driest part of Central Asia. Scientific explorations by Chinese and foreign researchers have been continuously conducted there since the mid- to late 1800s, and much progress has been made, but many issues remain hotly debated. Particularly intense debate focuses on the formation, environmental evolution, drying date of the Lop Nur lake, and cause of the helical salt crusts recently revealed by remote-sensing images. In this paper, we review the status of this research to provide insights that can inform studies in other arid zones that resemble the Lop Nur. The Lop Nur depression is a secondary unit of the Tarim Block, controlled by faults and fractures formed by the Himalayan orogeny, but various competing explanations have been proposed for how these geological structures gave rise to the depression. The depression''s formation date also remains unclear. Several boreholes have been created to reconstruct the environmental evolution at different time scales since the Quaternary, and deposition rates of lake sediments, especially since the Late Pleistocene, have averaged less than 1mm annually. The drying date of the Lop Nur lake is also debated. The helical salt crust structures appear to have formed as the lake shrank, but how and when they formed is unclear. Huge potash reserves have been found, and large-scale potash fertilizer production has begun, but the origin of these deposits is debated. Understanding the factors causing environmental evolution in this region is a central issue that will help us to clarify these and other debated issues. [Copyright &y& Elsevier]

Abstract: Afforestation is a primary tool for controlling desertification and soil erosion in China. Large-scale afforestation, however, has complex and poorly understood consequences for the structure and composition of future ecosystems. Here, we discuss the potential links between China''s historical large-scale afforestation practices and the program''s effects on environmental restoration in arid and semi-arid regions in northern China based on a review of data from published papers, and offer recommendations to overcome the shortcomings of current environmental policy. Although afforestation is potentially an important approach for environmental restoration, current Chinese policy has not been tailored to local environmental conditions, leading to the use of inappropriate species and an overemphasis on tree and shrub planting, thereby compromising the ability to achieve environmental policy goals. China''s huge investment to increase forest cover seems likely to exacerbate environmental degradation in environmentally fragile areas because it has ignored climate, pedological, hydrological, and landscape factors that would make a site unsuitable for afforestation. This has, in many cases, led to the deterioration of soil ecosystems and decreased vegetation cover, and has exacerbated water shortages. Large-scale and long-term research is urgently needed to provide information that supports a more effective and flexible environmental restoration policy. [Copyright &y& Elsevier]

Thermal regime and thermal history are of significant important in basin dynamics and hydrocarbon generation of source rocks. The sedimentary basins in three typical cratons of China, North China Craton (NCC), Yangtze Craton (YC) and Tarim Craton (TC), underwent completely different tectonic background and dynamic mechanism, which resulted in the differentials of their thermal regimes. In this paper, the thermal regimes of the Bohai Bay Basin in the eastern NCC, Tarim Basin in TC, and Sichuan basin in the Upper YC were studied. There has some lower thermal background in the area of western China than eastern side of the NCC. The mean heat flow value of Tarim basin is 42.5 mW/m2, 53.8 mW/m2 in the Sichuan basin and 66.7 mW/m2 in the eastern NCC. And the temperature at 10000 m ultra-depth in the Tarim Basin also shows lower values than that of Sichuan and Bohai Bay basins. The thermal history, modeled from thermal indicators of vitrinite reflectance (R o), equivalent vitrinite reflectance data (R equ), fission track and (U Th)/He data of apatite and zircon, evolved differently because of the different tectonic history in these basins. The Tarim basin underwent a cooling history with the heat flow of 55–65 mW/m2 in the Cambrian decreasing to the present-day of 40–50 mW/m2. The Meso-Cenozoic thermal history of the Bohai Bay basin experienced four evolutionary stages with two heat flow peaks in the late Early Cretaceous and in the Middle to Late Paleogene, which correspond to the destruction peaks of the eastern NCC and had heat flow values of 82–86 mW/m2 and 81–88 mW/m2, respectively. The Sichuan basin was stable with heat flow value of less than 65 mW/m2 from the Late Sinian to Late Paleozoic, and the heat flow increased rapidly to the peak value (75–100 mW/m2) at the end of Early Permian by thermal effect of the Emeishan mantle plume. From Mesozoic to present, the heat flow decreased to the present value (60–70 mW/m2). In addition, the comparation of thermal characteristics of typical cratons around the world, including heat flow, thermal history, lithospheric thermal structure and thermal lithospheric thickness, also have been caried out. The differential thermal histories of Tarim and Sichuan basins resulted in the different thermal evolution of Cambrian source rocks. This study may provide some new geothermal evidence for hydrocarbon generation and phase distribution of oil and gas in the deep and/or ultra-deep basin. Thermal regime and thermal history of typical sedimentary basins in three typical cratons of China underwent completely different evolution. The Tarim basin underwent a cooling history, the Bohai Bay basin experienced four evolutionary stages with two heat flow peaks, and the Sichuan basin was stable with heat flow but to a peak at the end of Early Permian. Nansheng Qiu, Chang Jian, Zhu Chuanqing, Liu Wen, Zuo Yinhui, Xu Wei, Li Dan. [Display omitted] • Three typical cratons of China show great differences in heat flow and deep-temperature. • Three typical cratons of China show great differences in lithospheric thickness from 76–170 km. • Thermal histories of Bohai Bay, Sichuan and Tarim basins are summarized. • Thermal regime between stable and destabilized cratons are compared. • Three thermal evolution patterns of source rocks are obtained. [ABSTRACT FROM AUTHOR]

The development of evaporite–carbonate assemblages is a common sedimentary process in restricted and evaporitic marine environments. These assemblages provide important reservoir spaces for oil and gas. To establish a systematic understanding of, and scientific basis for, oil and gas exploration, this paper reviews the major genetic environments of evaporite–carbonate assemblages and associated hydrocarbon reservoirs. Based on the review, carbonate reservoir-forming marine evaporite sequence worldwide can be categorized into four major settings: marginal-marine sabkhas, marginal-marine evaporative lagoons, coastal salinas and regional evaporite basins. In addition, a new type of reservoir that developed in the Ordos Basin of China during the Ordovician greenhouse is proposed based on a synthesis of new and existing chemical and physical data. This new model is identified in the supra-salt reservoir in the fifth Member of the Middle Ordovician Majiagou Formation in the Ordos Basin and is termed an "epeiric basin-scale moldic reservoirs". In this newly identified type of dolomite reservoir, irregular–circular moldic pores and vugs that are uniformly distributed in micritic dolomite matrix formed high-quality reservoir spaces, examples of which are rare worldwide to date. The primary evaporitic mineral in these molds is disseminated halite crystal, which formed in a restricted and evaporitic epeiric-basin environment. The selective dissolution of disseminated halite crystals and enlargement of its surrounding rocks in the upper part of the sedimentary cycle by meteoric water during late highstand system tract formed the unique distribution of halite-moldic pores and vugs. Within the evaporitic epeiric basin, high-frequency sea-level fluctuation and syngenetic exposure are also likely to have occurred, conditions that have been neglected in the classic models. Coupling of the extremely high atmospheric CO 2 content, low-amplitude location and high-frequency sea-level fluctuations during the Middle Ordovician greenhouse, together with the flat and broad restricted evaporative environment, controlled the formation of this rare end-member sedimentary assemblage and associated reservoirs. The reservoirs were developed within the sedimentary framework of the North China Platform, which was characterized by a general depression surrounded by three uplifted areas during the Middle Ordovician Majiagou period. The model characterized by epeiric basin-scale disseminated evaporites allowed the formation of reservoirs with high exploration potential. Exploration of this type of reservoir requires that attention is paid to hydrocarbon sweet spots generated by later diagenesis and to heterogeneous hydrocarbon accumulation. [ABSTRACT FROM AUTHOR]

Abstract: Wetland plant communities persisted though much of the Pennsylvanian in Euramerica and are the dominant coal forming vegetation in this region. Distribution of these floras show a dramatic decline at the end of the Carboniferous with many of the plant genera and species becoming extinct by the onset of the Permian. This has been correlated with climate change and in particular aridification associated with northwards plate motion and Euramerica moving into the doldrums, but is also associated with the Variscan orogeny and forefront destroying large areas of formerly lowland basinal settings. Other factors may include Pennsylvanian glaciations as evidenced by cyclothem and rhythmical deposition in lowlying wetland settings, and change in eustatic base level. Evidence from Euramerica demonstrates extinction of this kind of wetland biota by the earliest Permian and the development of drier floras including conifer dominated assemblages. However, new data from other parts of the world, most notably North China, confirm this model and highlight the presence of similar coal swamps ranging from the Late Pennsylvanian through the Permian. In this paper we summarise and synthesize recent taxonomic and systematic investigations undertaken on the plant fossils from the Pennsylvanian Benxi Formation – the oldest recognised wetland plant community in China – and the Early Permian Taiyuan Formation – the best preserved wetland plant community from China. Results indicate a remarkable similarity of the Pennsylvanian–Early Permian floras of North China with the older assemblages in the Pennsylvanian of Euramerica, and the presence of typical ‘Euramerican’ coal swamp plant families, genera and in some cases species in China. Conclusions include the presence of the Ameriosinian phytogeographical realm uniting Euramerica and northern Cathaysia at this time, coal swamps in the Permian of North China evolving from a ‘Euramerican’ origin, and the dramatic floral turnover at the end of the Carboniferous representing a regional event rather than a global extinction episode. Patterns of plant distribution through this interval have profound implications on established palaeogeographical models and support continental connection between Euramerica and Cathaysia before the end of the Carboniferous, contradicting ideas of Cathaysian island biogeography and biotic distinction. Continental connection appears to be related to glacial eustatic low-stand and previously shallow marine environments becoming vegetated. Also important is the fact that in both Euramerica and North China the pattern of floristic demise within wetland plant communities are similar to each other, implying the same causal mechanisms, with plants occupying waterlogged positions being the most severely devastated. However, ecosystem demise occurred at the end of the Carboniferous in Euramerica and in the middle Permian in North China, but in both cases the primary cause was climate change. [Copyright &y& Elsevier]

Understanding the processes that lead to the lithosphere thinning is a key aspect of continental geology research. In this paper, we present essential observations and summarize our understandings on the lithosphere thinning and accompanying magmatism in eastern continental China since the Mesozoic as a straightforward consequence of plate tectonics. We show that the lithosphere thinning in the Mesozoic resulted from basal hydration weakening with the water coming from dehydration of the paleo-Pacific plate in the mantle transition zone. The weakening effect is to convert the basal lithosphere into asthenosphere by reducing its viscosity, having thus thinned the lithosphere while triggering mantle melting and crustal magmatism marked by the widespread Mesozoic basalts and granitoids in space and time. These observations and logical reasoning require the existence and effect of subducted paleo-Pacific plate in the mantle transition zone, whose active subduction ended at ~ 90 Ma with the suture located off the continental China marked by the arc-shaped southeast coastline. As a result, the thinned lithosphere began a 40-Myr period (i.e., ~ 90 to ~ 50 Ma) of basal accretion manifested by compositional systematics of basalts erupted in this period. The initiation of the present-day western Pacific subduction at ~ 50 Ma and its eastward retreat caused eastward drift of continental China, leaving the older portions of the present-day Pacific slab stagnant in the mantle transition zone with resumed water supply in the form of hydrous melt to maintain the thinned lithosphere, which is the same as creating and maintaining the oceanic-type seismic low velocity zone (LVZ) beneath eastern China, responsible for the Cenozoic alkali basalt volcanism in the region. That is, the present-day lithosphere-asthenosphere boundary (LAB) beneath eastern China is a petrological boundary, either as an amphibole dehydration solidus or water-saturated solidus. As predicted, the Cenozoic alkali basalts in eastern China demonstrate that lithosphere thickness (i.e., the LAB depth) controls the compositions of mantle melts, i.e., the lid effect. The latter further confirms the LAB beneath eastern China as a solidus, below which decompression melting happens, and above which melt solidifies or ascends rapidly to the surface. Our studies thus lead us to the unavoidable conclusion that the lithosphere thinning in the Mesozoic, the present-day LAB, the seismic LVZ and the widespread Mesozoic-Cenozoic magmatism in eastern China are all consequences of plate tectonics in response to paleo-Pacific plate subduction, which is of global significance for understanding intra-continental magmatism at present and in Earth's histories. [ABSTRACT FROM AUTHOR]

From the latest Cretaceous (late Campanian to Maastrichtian, ~75–66 Ma) to the earliest Paleogene, fluctuations in greenhouse climate, inferred primarily from marine sediments, have been linked to volcanism, the Chicxulub asteroid impact, and the Cretaceous-Paleogene (K-Pg) mass extinction. In this paper, we summarize terrestrial climate records in mid-latitude East Asia during the latest Cretaceous and across the K-Pg boundary, based on a multi-proxy approach from the geochronologically well-constrained Sifangtai and Mingshui formations (SMF), accessed by scientific drilling of the Songliao Basin in northeastern China. Evolution of sedimentary environments is characterized by five depositional units of fluvial-deltaic-lacustrine facies. Development of four types of paleosols, including Inceptisols, Aridisols, Vertisols and Alfisols, is interpreted to primarily reflect climatic changes. Correlations among sedimentary facies, paleosol features, illite chemistry index, chemical index of alteration, as well as stable and clumped isotopes of pedogenic carbonates and clay minerals of the SMF validate their reliability for paleoclimate reconstruction, and indicate significant fluctuations in terrestrial climate and sedimentary environment. During global warming intervals possibly triggered by volcanism (e.g. ~69.5–68.5 Ma), the Songliao Basin experienced a warmer and wetter climate with stronger terrestrial chemical weathering and more monsoon-derived moisture sourced from the Pacific. In contrast, during global cooling intervals (e.g. ~70.5–69.5 Ma and ~ 68.5–66.5 Ma), the SMF record a cooler and drier climate with less intensive chemical weathering and more westerlies-derived moisture. Across the K-Pg boundary, dramatic changes in land temperatures and hydroclimate correspond to the latest Maastrichtian warming episode (~66.4–66.1 Ma), the transient cooling preceding the K-Pg boundary (~66.1–66.0 Ma), and the earliest Paleogene warming interval (~66.0–65.7 Ma). Temporal correlation of weathering index changes with the Deccan Traps volcanism suggests that volcanism and subsequent intensified weathering played a major role for climatic changes across the K-Pg boundary. The integrated records of sedimentological and geochemical datasets from the Songliao Basin robustly demonstrate that the terrestrial climate of mid-latitude East Asia responded strongly to greenhouse climate changes and to the catastrophic geological events from the latest Cretaceous to the earliest Paleogene. [ABSTRACT FROM AUTHOR]

With a depositional history spanning the early Aptian to early Albian (~19 mys), the Lower Cretaceous Xinminpu Group in Jiuquan, NW China provides detailed record of an inland ecosystem responding to global climatic and environmental changes. The Xinminpu Group exhibits the most typical elements of the Jehol Biota found outside NE China, a highly diverse avifauna and a mid-Cretaceous angiosperm flora. The absence of a comprehensive stratigraphical framework for this area however limits the degree to which the unit can be interpreted relative to coeval sections and the geological records in genera. Recent fossil discoveries and radio-isotopic age data can provide a more detailed biostratigraphical and chronostratigraphical framework for Lower Cretaceous units around Jiuquan. The data complied here indicate that the Chijinpu Formation correlates with the middle-upper Yixian and lower Jiufotang formations of NE China making it early Aptian in age, and the Xiagou Formation correlates with the upper Jiufotang and Shahai formations making it late early Aptian-early Albian in age. This research further reports a novel zircon U-Pb age constraint of 112.4 ± 0.3 Ma for a basalt sample from the lowermost Zhonggou Formation, which is supported to be correlated with the Fuxin Formation of early Albian age. The Chijinpu Formation contains typical elements of the Jehol Biota, i.e. the Eosestheria - Lycoptera - Ephemeropsis trisetalis assemblage, confirming the interpretation that the Jehol Biota had reached Jiuquan during its second evolutionary stage. The Xiagou Formation contains the amphibious avifauna appearing just above OAE1a, indicating a close link between the early Ornithuromorpha evolution and early Aptian global climate changes. The Zhonggou Formation in Jiuquan records the first appearance of an angiosperm flora above OAE1b. Depositional indicators suggest a humid climate with a gradual shift to arid conditions during this time. This review paper laid foundation for the systematic study of the well-preserved Early Cretaceous ecosystem in Jiuquan, allowing to understand correlations between inland and marine environments as recorded in sediments from this critical period. • We establish the stratigraphy and time scales for the Lower Cretaceous in Jiuquan. • We review how a Cretaceous inland ecosystem responded to global climatic change. • This study summarizes the detailed fossil records for the Jehol Biota in NW China. • Robust age for the less-studied outcrops allows to test the Jehol radiations. • A close link existed between early Ornithuromorpha evolution and OAE1a. [ABSTRACT FROM AUTHOR]

Seismic anisotropy, as a ubiquitous feature in the Earth's interior, could record the past lithospheric deformation and map directly mantle flow within our planet, and thus becomes a bridge to understand the interaction between the crust and subcrustal mantle or between different tectonic blocks. Plenty of high quality shear-wave splitting (SWS) measurements have been performed in Mainland China. In this paper, we compile these measurements, and then analyze their characteristics, estimate the contribution from the crust, lithospheric mantle and asthenosphere, and explore their mechanisms and tectonic/geodynamic implications. [ABSTRACT FROM AUTHOR]

Aeolian dust has a great influence on mountain hydrology, climate, and biogeochemical cycles. Dust deposited on glaciers and snowpack of the high alpine mountains in Tibetan Plateau (TP) and its surrounding regions can provide a unique method of determining the high-elevation transport and deposition of Asian dust in the middle and upper troposphere. Long-range-transported (LRT) Asian dust is often transmitted through the high troposphere, thus studies on dust deposition in the high-elevation cryosphere can reflect the LRT information of aeolian dust, and provide an unparalleled record to understand the regional climate and environment change in the "Third Pole" region. This paper comprehensively reviews the current status of the major factors that determine aeolian dust transport, settling, and cycling, and the key components of this dust cycles in high-elevation cryosphere regions, revealed by glacial snowpack and ice-core dust geochemistry recorded in the mountain glacier areas of TP and western China. Research on glacial dust concentrations indicated that much higher amounts of aeolian dust were found to transport and cycle in the high-elevation troposphere over TP and surroundings, compared to other locations of the globe. Dust concentrations and fluxes in high elevation regions of the TP were closely related to the transport distance of the nearby dust sources (e.g. large deserts and Gobi in western China, and arid deserts on the plateau surface). Isotopes tracers (e.g. 87Sr/86Sr, and ε Hf , ε Nd) and dust size distributions revealed that aeolian dust transported over TP mainly originated from the arid and semi-arid deserts and surface crust soils on TP; Aeolian dust from the large deserts of central Asia (e.g. the Taklimakan Desert with small ratio) have not been easily transported to the hinterland of TP under the current climatic conditions. An End-Member Mixing Analysis model was also used to calculate the relative contributions of northern hemisphere dust sources to the TP glacier dust sinks. The marked spatial differences in LRT dust sources of TP glaciers were caused by the large-scale atmospheric circulation strength and interactions in the Asian region. In addition, Asian dust has a large influence on the radiative forcing of glacier and snow melt in which the iron oxide composition constitute an important driving factor. Biogeochemical cycles in cryospheric regions were significantly affected by aeolian dust cycles, influencing glacial ecosystems, meltwater geochemistry (e.g. d Fe release) and nutrients supply for downstream aquatic ecosystems. Ice core records for the past hundred years revealed a general decreasing trend of dust storm frequency and atmospheric concentration over the TP region. This work provides new insights and perspectives on aeolian dust transport and cycling in high regions of the troposphere and cryosphere of the TP, identifying critical uncertainties and priorities for future research. [ABSTRACT FROM AUTHOR]

• This study reviews and lists all Chinese papers on Devonian miospores. • The Late Devonian miospore diversity was greatly overestimated. • The rise of land plants and the oxygenation event are discussed. • The spore diversity is affected by both climate and sea-level changes. The microfossil-based pattern of the Devonian land plants of China is revised and discussed based on a new, comprehensive dataset. This dataset compiles the chronostratigraphical distribution of 1677 species belonging to 190 genera of spores and pollen from the primary literature, which covers the history of fossil Chinese terrestrial palynofloras. From this, we describe the patterns and biodiversity dynamics using both range-based and sample-based data to illustrate the main fluctuations of Devonian taxonomic richness, including rarefaction by filtering out uneven sampling. Results show that the apparent terrestrial palynofloral diversity of China increases progressively from the Early to Middle Devonian, with a genuine Givetian peak followed by a plateau persisting during the Late Devonian. Results further suggest that sampling effects may strongly influence the perception of biodiversity trends in China, as well as that the observed Late Devonian taxonomic diversification may have been greatly overestimated. Compiled evidence is discussed in the light of the global evolution of marine-terrestrial ecosystems. We hypothesize that the rise of Devonian floras may have played a remarkable role in an oceanic oxygenation event during this Period. [ABSTRACT FROM AUTHOR]

Although there are still slight differences during some periods, the global surface air temperature (SAT) change series developed by different groups are generally very consistent with each other. However, there are still considerable uncertainties in the analysis of air temperature series at the regional scale. At the slightly larger sub-continental scale, to understand the trend and magnitude of regional climate warming in China, many teams of scientists have tried to establish a series of air temperature changes across the country from the 1880s onwards. However, until recently, the conclusions reached by these different teams remained markedly different, implying clear uncertainties. The reasons for the uncertainties are inhomogeneities in some SAT series, incomplete data and the biased nature of the station distribution. In addition, many studies have attributed the rapid warming rates in China to contributions from urbanization. However, additional research has shown that the characteristics of the periodic variations in temperature change across China in recent decades indicate that China has warmed faster than other areas at the same latitude and the average for the Northern Hemisphere. Although rapid urbanization in some parts of China has led to local-scale warming, due to the relatively small overall sizes of urbanized areas, the latest conclusions confirm that urbanization contributed less than 5 % of the regional air temperature changes in China over the past century. Since approximately 1998, the general characteristics of air temperature changes in China have also shown warming, but more in extremes than average values. These phenomena can be explained by the physical mechanisms of atmospheric circulation changes. This paper discusses all these issues including summarizing the process and experience of establishing a series of air temperature changes at the sub-continental scale and estimating the magnitude of climate change by developing a series of regional temperature changes throughout the 20th century. [ABSTRACT FROM AUTHOR]

China's Loess Plateau is the largest loess deposit in the world in terms of both depth and area. Water storage in soils of the Plateau has direct impacts on food security, human health and ecosystem function. Despite extensive research on the behavior and function of soil water in the Plateau, there is no state-of-the-art review that presents research achievements, gaps and future perspectives. This paper reviews the advances in soil water research and highlights future research needs and challenges in the Loess Plateau, and thereby provides informed decision on sustainable water management. We report that considerable efforts have been made to investigate: i) soil water movement and hydraulic property estimation in the typical loess regions; ii) spatial and temporal variations in soil water content and storage at multiple scales; iii) dried soil layers induced by excessive water use from unreasonable artificial revegetation; and iv) soil water availability and water carrying capacity of typical vegetation types on the Loess Plateau. These studies have greatly enhanced our understanding about the fundamental characteristics, spatio-temporal patterns and natural and anthropogenic controls of soil water distribution and water cycles in the Loess Plateau, which in turn have important implications for the regulation and management of water resources toward sustainable ecological construction. Based on the identified key issues and future research priorities, recommendations were drawn to address unsolved problems, including: i) processes and mechanisms controlling water transport and interactions within the groundwater–soil–plant–atmosphere continuum; ii) how soil hydrological processes couple nutrient cycles in response to climate change and human activities; and iii) development of quantitative models across spatial scales for modeling changes in thresholds of soil water carrying capacity for vegetation. The incorporation of research findings into policy and practice can improve soil water management that will in turn significantly benefit the promotion of ecosystem services and functions in the Loess Plateau. [ABSTRACT FROM AUTHOR]

The Meso-Neoproterozoic period, sometimes referred to as the 'boring billion' or 'Earth's middle age', spans the interval between the formation of the Columbia and Rodina supercontinents. It is regarded as a stable era of the Earth. However, from a global perspective, there are many intensive events of mafic volcanism, dyke intrusions and formation of rift basins recorded in different cratons during this period. This paper focuses on rift basins that developed in three cratons in China (North China, South China and Tarim cratons), because large-scale primary gasfields, as one of the deep resources, have been discovered recently in rocks of Meso-Neoproterozoic age. The formation mechanisms and tectonic settings of these rift basins as the targets of Deep Earth are discussed, based on the restoration of global positions of the three cratons by pre-existing paleomagnetic data and plate reconstruction. We recognise that the rift basins of the North China Craton are related to extrusion tectonics in the southwest Ordos Block or are pull-apart basins along the northern and southern sides of the Ordos Block. The rift basins of the South China Craton are derived from mantle lithospheric delamination of the Jiangnan Orogen in the eastern South China Craton or subduction retreat and backarc opening in the western South China Craton, respectively. The rift basins of the Tarim Craton originated from the backarc opening along the margin of the Supercontinent Rodinia. [ABSTRACT FROM AUTHOR]