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Savanna-like vegetation and dry thickets occur in hot dry valleys across southwestern China. Here, the flora and biogeography in hot dry valleys with savanna-like vegetation in SW China are studied. Native seed plants of 3217 species and varieties from 1038 genera in 163 families are recorded from these hot dry valleys. The biogeographical elements with a tropical distribution contribute 57.18%, but the ones with a temperate distribution contribute 36.45% of the total genera of the flora. This implies that the flora in hot dry valleys is of tropical margin nature and has been influenced by temperate elements. Floristic divergence across these hot dry valleys is obvious. The floras in the Yuanjiang and the Nujiang valleys are dominated by tropical elements (with a tropical distribution) (77.26% and 74.49 of the total genera, respectively), but the flora of the Jinshajiang valley is composed of half tropical (47.27%) and half temperate (44.96%) genera. Regarding floristic similarities, the Jinshajiang shows the highest similarity to the Yuanjiang although these river valleys are located a great distance from each other. We hypothesize the geological events in Yunnan could profoundly influence the flora and its divergence of the savanna-like vegetation in these deep, hot dry river valleys. Our results could be well explained from the geological events since the Cenozoic, such as the uplift of Himalayas, the extrusion of Indochina, the river capture of the Jinshajiang separating from the Yuanjiang, and the northward movement of the Burma Plate. Our study could be clues to explore the possible formation of the savanna-like vegetation. Keywords Flora * Biogeography * Savanna-like vegetation * Hot dry valleys * Geological history * SW China, Introduction The savanna-like vegetation or dry thickets, including woodland and dry thorny shrubs, occur in hot dry valleys and some dryer habitats in southeastern Asia (Blasco et al., 1996). Scholes [...]

The Upper Triassic Chang 7 Member lacustrine organic-rich shale of the Yanchang Formation of the Ordos Basin is a significant hydrocarbon source rock containing abundant of tuff intervals ranging from millimeters to tens of centimeters thick. The present study relies upon petrographic and geochemical data of Chang 7 tuff intervals and organic-rich shale to consider fertilization of the lake surface by volcanic debris as a triggering mechanism of black shale sedimentation. Paleoproductivity proxies, including P/Al, Ni/Al, and Cu/Al, display elevated values in association with tuff intervals, suggesting increased productivity induced by volcanic nutrient seeding of the lake surface. Moreover, vertical variations of TOC mimic trends of paleoproductivity proxies, indicating that primary productivity was critical to organic carbon enrichment of the Chang 7 Member. Previous studies have postulated that lake bottom redox conditions were predominantly oxic--suboxic during deposition of the Chang7and that these deposits accumulated slowly, neitherofwhich would have favored the export and preservation of organic matter in the absence of enhanced productivity. Accumulation of the organic-rich Chang 7 shale demonstrates the critical role that intensified primary productivity triggered by volcanism can play in the accumulation of carbonaceous sediment.Le shale lacustre riche en matiere organique du membre Chang 7 du Trias superieur de la Formation de Yanchang du bassin d'Ordos est une importante roche-mere d'hydrocarbures renfermant d'abondants intervalles de tuf d'epaisseur millime-trique a decimetrique. Nous utilisons des donnees petrographiques et geochimiques d'intervalles de tuf et de shale riche en matiere organique du membre Chang 7 pour examiner la fertilisation de la surface de lacs par des debris volcaniques comme mecanisme declencheur du depot de shale noir. Des variables substitutives de la paleoproductivite, dont les rapports P/Al, Ni/Al et Cu/Al, presentent des valeurs elevees associees aux intervalles de tuf, ce qui indiquerait une productivite accrue induite par l'ensemencement de la surface de lacs par des nutriments d'origine volcanique. Les variations verticales du COT suivent en outre les tendances des variables de paleoproductivite, ce qui indique que la productivite primaire jouait un role cle dans l'enrichissement en carbone organique du membre Chang 7. Des etudes anterieures ont postule que les conditions d'oxydoreduction du fond des lacs etaient principalement oxiques a suboxiques durant le depot du membre Chang 7 et que ces sediments se sont accumules lentement, ni l'une ni l'autre de ces situations ne favorisant l'exportation et la preservation de matiere organique en l'absence d'une productivite accrue. L'accumulation du shale riche en matiere organique du membre Chang 7 demontre le role cle que l'intensification de la productivite primaire causee par le volcanisme peut jouer dans l'accumulation de sediments carbones. [Traduit par la Redaction], IntroductionThe association of volcanic ash deposits or tuff intervals and organic-rich hydrocarbon source rocks has been described from basins of various ages and locations (Dawson 2000; Su et al. 2003; [...]

ABSTRACT This article reviews current evidence for the origins of domestic cattle in China. We describe two possible scenarios: 1) domestic cattle were domesticated indigenously in East Asia from the [...]

Tropical and subtropical ecosystems, especially those found on limestone substrates, are among the most diverse terrestrial habitats in China. However, little is known about patterns of plant diversity, ecology and conservation status within these ecosystems. In this special issue we present five reviews and/or in-depth studies of these tropical Chinese plants and ecosystems that capture current research efforts in tropical China plant ecology. Keywords Biodiversity conservation * Tropical botany * Tropical forests * Tropical China * Karst * Gesneriaceae * Hainan * Tiankeng * Orchid germination, China is known for its rich plant diversity, especially the mountain flora in the west and the eastern temperate area (Huang, 2011). In contrast, plant diversity and plant species conservation [...]

Forest ecosystems contain large amounts of soil organic carbon (SOC), which is a major component of biogeochemical cycles that may be sensitive to environmental change. We used a combination of nuclear magnetic resonance (NMR) spectroscopy and elemental and isotopic composition to examine the influence of soil properties and climatic factors on the quantity and degree of decomposition of SOC for organic and surface mineral horizons in seven oriental oak (Quercus variabilis Blume) forest sites arranged across a 11° latitudinal gradient in East China. Lacking Oa horizons, the two southernmost sites contained lower amounts of SOC in the forest floor horizon, but otherwise, latitudinal trends were not consistent. The SOC stock in the 0-10 cm mineral horizon exhibited no clear trend along the gradient and had a negative association with clay + silt content. Based on a higher alkyl/O-alkyl (A/O) ratio and alkyl/methoxyl (A/M) ratio, the SOC at the 0-10 cm depth appeared to be relatively more decomposed in three of the four southern subtropical sites. However, the degree of SOC degradation also decreased strongly with increasing soil pH ([R.sup.2] = 0.90, P = 0.001). Soil organic carbon exhibited increases in δ[sup.13]C and δ[sup.15]N and decreases in the C/N ratio with depth for all the seven sites, indicating an increase in its extent of decomposition. Our analysis indicated that the A/M ratio from NMR provided the best indication of the extent of SOC degradation along the latitudinal transect, whereas the elemental and isotopic composition better reflected patterns with soil depth. Key words: soil organic matter, soil properties, climate, CP-MAS [sup.13]C NMR, δ[sup.13]C, δ[sup.15]N. Les ecosystemes forestiers contiennent de grandes quantites de carbone organique du sol (COS) lequel est une composante majeure des cycles biogeochimiques qui peuvent etre sensibles aux changements environnementaux. Nous avons combine la spectroscopie de resonnance magnetique nucleaire (RMN) avec la composition elementaire et isotopique pour etudier l'influence des proprietes du sol et des facteurs climatiques sur la quantite et le degre de decomposition du COS dans les horizons organique et mineral de surface dans sept stations de foret de chene oriental (Quercus variabilis Blume) reparties le long d'un gradient latitudinal de 11° dans l'est de la Chine. Ne comportant pas d'horizon Oa, les sols des deux stations les plus meridionales contenaient des quantites plus faibles de COS dans la couche holorganique mais les tendances latitudinales n'etaient par ailleurs pas consistantes. Le stock de COS dans l'horizon mineral de 0-10 cm ne montrait aucune tendance nette le long du gradient et avait une relation negative avec le contenu en argile + limon. Sur la base des ratios alkyle/O-alkyle (A/O) et alkyle/methoxyle (A/M), le COS present a une profondeur de 0-10 cm semblait relativement plus decompose dans trois des quatre stations subtropicales situees au sud. Cependant, le degre de degradation du COS diminuait aussi fortement avec l'augmentation du pH du sol ([R.sup.2] = 0,90, p = 0,001). Le COS montrait une augmentation du δ[sup.13]C et du δ[sup.15]N ainsi qu'une diminution du ratio C/N avec la profondeur dans toutes les stations, indiquant que le degre de sa decomposition augmentait. Notre analyse indique que le ratio A/M obtenu par RMN fournit la meilleure indication du degre de degradation du COS le long d'un transect latitudinal tandis que la composition elementaire et isotopique reflete mieux le profil en fonction de la profondeur dans le sol. [Traduit par la Redaction] Mots-cles : matiere organique du sol, proprietes du sol, climat, RMN [sup.13]C CP-MAS, δ[sup.13]C, δ[sup.15]N., 1. Introduction Forest ecosystems in the Northern Hemisphere cover 2 x [10.sup.9] ha and contain large amounts of carbon (C, 390 Pg), representing a huge reservoir of C on a [...]

Environmental archaeology in northeastern China has reached a critical period of development, although the state of progress varies across this large geographical region. The lack of collaboration between archaeologists and associated scientists remains the main obstacle in current research. Almost exclusively conducted by dedicated scientists, research in the field is often ignored by archaeologists because it is not presented within an archaeological context. Furthermore, the research is not of a high spatial and temporal resolution: there is the tendency to make broad generalizations about large regions over long periods of time and to disregard areas that do not fit their general climatic models. Another problem is the misguided borrowing of concepts developed in other parts of the world, for example, the Holocene Climate Optimum (HCO), which is well defined in prehistoric Europe but is still being developed in China. Many researchers have simply applied this term to the same period in China and assumed that the climate around that period resembled that of prehistoric Europe, despite the fact that this is currently unsupported by local palaeo-environmental evidence. Other obstacles to the development of environmental archaeology include deterministic approaches and oversimplistic research procedures. To address these problems, a conversion of qualitative data to quantitative data on temperature and precipitation is required. Future research should be conducted by teams of scientists and archaeologists working collaboratively on both natural and archaeological deposits, in order to establish a strong foundation for further environmental reconstruction research. Keywords: Northeast China, environmental archaeology, environmental determinism, high resolution, quantitative approaches., INTRODUCTION This article focuses on the field of environmental archaeology in the northeastern region of China, although a few external examples of archaeological work in other regions will also be [...]

The U-Pb geochronology of 687 detrital zircons from the voluminous Upper Neoproterozoic--Ordovician succession in the Wuyishan Fold Belt of South China reveals a common dominant c. 1200-950 Ma group, indicative of an outboard provenance terrane with a Grenville-age province to the southeast during the late Neoproterozoic--Early Palaeozoic. Compared with coeval samples from the Gondwanan and eastern Laurentian margins, our data show a scarcity of distinctive Gondwanan provenances (c. 650-500 Ma) and reveal some Laurentian signatures. These results argue against the peri-Gondwanan setting for South China during the late Neoproterozoic--Ordovician, instead implying a Laurentian affinity. Keywords: South China, detrital zircon, Grenville-age province, continental affinity, Laurentia doi: 10.1017/S0016756810000725

Pseudagnostus rugosus Ergaliev, 1980 is described from the Furongian Ctenopyge tumida Zone at Gisl6vshammar, Scania, southern Sweden. This is the first record of this distinctive agnostoid in Scandinavia. The species is known previously from Malyi Karatau, Kazakhstan, and northwestern Hunan and western Zhejiang, South China, and provides a newly recognized link between middle-upper Furongian successions in Baltica, Kazakhstan and South China. The occurrences of P. rugosus allow a correlation between the C. tumida Zone of Baltica, the lower Eolotagnostus scrobicularis-Jegorovaia Zone of Kazakhstan and the lower Lotagnostus americanus Zone of South China. Keywords: agnostoids, Pseudagnostus, correlation, biostratigraphy, Furongian, Sweden. doi:10.1017/S0016756810000282

The Khanka Massif is a crustal block located along the eastern margin of the Central Asian Orogenic Belt (CAOB) and bordered to the east by Late Jurassic-Early Cretaceous circum- Pacific accretionary complexes of the Eastern Asian continental margin. It consists of graphite-, sillimanite- and cordierite-bearing gneisses, carbonates and felsic paragneisses, in association with various orthogneisses. Metamorphic zircons from a sillimanite gneiss from the Hutou complex yield a weighted mean [sup.Pb]206pb/[238.sup.U] age of 490 [+ or -] 4 Ma, whereas detrital zircons from the same sample give ages from 934-610 Ma. Magmatic zircon cores in two garnet-bearing granite gneiss samples, also collected from the Hutou complex, yield weighted mean [sup.206][pb/.sup.Z38]U ages of 522 [+ or -] 5 Ma and 515 [+ or -] 8 Ma, whereas their metamorphic rims record [sup.206][pb/.sup.23]SU ages of 510 500 Ma. These data indicate that the Hutou complex in the Khanka Massif records early Palaeozoic magmatic and metamorphic events, identical in age to those in the Mashan Complex of the Jiamusi Massif to the west. The older zircon populations in the sillimanite gneiss indicate derivation from Neoproterozoic sources, as do similar rocks in the Jiamusi Massif. These data confirm that the Khanka Massif has a close affinity with other major components of the CAOB to the west of the Dun-Mi Fault. Based on these results and previously published data, the Khanka Massif is therefore confirmed as having formed a single crustal entity with the Jiamusi (and possibly the Bureya) massif since Neoproterozoic time. Keywords: SHRIMP U-Pb dating, Neoproterozoic, Late Pan-African, granulites, Khanka Massif. doi:10.1017/S0016756810000063

The Ediacaran Period (635 to 542 million years ago) was a time of fundamental environmental and evolutionary change, culminating in the first appearance of macroscopic animals. Here, we present a detailed spatial and temporal record of Ediacaran ocean chemistry for the Doushantuo Formation in the Nanhua Basin, South China. We find evidence for a metastable zone of euxinic (anoxic and sulfidic) waters impinging on the continental shelf and sandwiched within ferruginous [Fe(II)-enriched] deep waters. A stratified ocean with coeval oxic, sulfidic, and ferruginous zones, favored by overall low oceanic sulfate concentrations, was maintained dynamically throughout the Ediacaran Period. Our model reconciles seemingly conflicting geochemical redox conditions proposed previously for Ediacaran deep oceans and helps to explain the patchy temporal record of early metazoan fossils. 10.1126/science.1182369

The Hongshan societies of northeastern China are among East Asia's earliest complex societies. They have been known largely from elaborate burials with carved jades in ceremonial platforms. The most monumental remains are concentrated in a 'core zone' in western Liaoning province. Residential remains are less well known and most investigations of them have been in peripheral regions outside the core zone. Recent regional settlement pattern research around the well known ceremonial site of Dongshanzui has begun to document the communities that built and used Hongshan core zone monuments and to assess their developmental dynamics. The core zone, like the Hongshan periphery, appears to have been organized into a series of small chiefly districts within which ceremonial activities were important integrative forces. Their estimated populations of less than 1,000 are not much larger than those of districts in the periphery, and the evidence does not suggest that these districts were integrated into any larger political entity. The greater elaboration of core zone monumental architecture is thus not attributable to demographically larger communities or to larger-scale political integration. Future research should focus on documenting the organization of statuses and economic activities within these core zone communities to assess potential differences from peripheral communities in these regards. chiefdoms | comparative archaeology | China | Hongshan communities | regional settlement doi/10.1073/pnas.1000949107

Byline: Binhui Liu (1), Mark Henderson (2), Yandong Zhang (1), Ming Xu (3,4) Abstract: The timing, length, and thermal intensity of the climatic growing season in China show statistically significant changes over the period of 1955 to 2000. Nationally, the average start of the growing season has shifted 4.6--5.5 days earlier while the average end has moved 1.8--3.7 days later, increasing the length of the growing season by 6.9--8.7 days depending on the base temperature chosen. The thermal intensity of the growing season has increased by 74.9--196.8 growing degree-days, depending on the base temperature selected. The spatial characteristics of the change in the timing and length of the growing season differ from the geographical pattern of change in temperatures over this period but the spatial characteristics of change in growing degree-days does resemble the pattern for temperatures, with higher rates in northern regions. Nationally, two distinct regimes are evident over time: an initial period where growing season indicators fluctuate near a base period average, and a second period of rapidly increasing growing season length and thermal intensity. Growing degree-days are highly correlated with March-to-November mean air temperatures in all climatic regions of China the length of the growing season is likewise highly correlated with March-to-November mean air temperatures except in east, southeast and southwest China at base temperature of 0degC and southeast China at base temperature of 5degC. The growing season start date appears to have the greater influence on the length of the growing season. In China, warmer growing seasons are also likely to be longer growing seasons. Author Affiliation: (1) College of Forestry, The Northeast Forestry University, Harbin, 150040, China (2) Public Policy Program, Mills College, Oakland, CA, 94613, USA (3) Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A Datun Road, Beijing, 100101, China (4) Center for Remote Sensing and Spatial Analysis, Department of Ecology, Evolution and Natural Resources, Rutgers University, 14 College Farm Road, New Brunswick, NJ, 08901, USA Article History: Registration Date: 31/07/2009 Received Date: 28/12/2007 Accepted Date: 28/05/2009 Online Date: 11/09/2009

Wind-blown sands were mobile at many sites along the desert margin in northern China during the early Holocene (11.5-8 ka ago), based on extensive new numerical dating. This mobility implies low effective moisture at the desert margin, in contrast to growing evidence for greater than modern monsoon precipitation at the same time in central and southern China. Dry conditions in the early Holocene at the desert margin can be explained through a dynamic link between enhanced diabatic heating in the core region of the strengthened monsoon and increased subsidence in drylands to the north, combined with high evapotranspiration rates due to high summer temperatures. After 8 ka ago, as the monsoon weakened and lower temperatures reduced evapotranspiration, eolian sands were stabilized by vegetation. Aridity and dune mobility at the desert margin and a strengthened monsoon can both be explained as responses to high summer insolation in the early Holocene.

Newly obtained foraminifer faunas from the Permian-Triassic (P-Tr) transition at the Dajiang and Bianyang sections in the Nanpanjiang Basin, South China, comprise 61 species in 40 genera. They belong to the Palaeofusulina sinensis Zone, the youngest Permian foraminifer zone in South China. Quantitative analysis reveals that the last occurrences of more than a half of species (28/54) fall into a 60-cm-interval at the uppermost Changhsingian skeletal packstone unit and thus calibrate the end-Permian extinction to the skeletal packstonecalcimicrobial framestone boundary. About 93% (54/58) of species of the latest Permian assemblage became extinct in the P-Tr crisis. Four major foraminiferal groups, the Miliolida, Fusulinida, Lagenida, and Textulariina, have extinction rates up to 100%, 96%, 92%, and 50%, respectively, and thus experienced selective extinctions. Both Hemigordius longus and ?Globivalvulina bulloides temporarily survived the end-Permian extinction event and extended into the earliest Triassic but became extinct soon after. The post-extinction foraminifer assemblage is characterized by the presence of both disaster taxa and Lazarus taxa. Foraminifer distribution near the P-Tr boundary also reveals that the irregular contact surface at the uppermost Permian may be created by a massive submarine dissolution event, which may be coeval with the end-Permian mass extinction. A new species, Rectostipulina hexamerata, is described here.

The Guadalupian--Lopingian boundary stratotype at Penglaitan, and the nearby Tieqiao section, near Laibin, South China, record a series of major environmental changes within the Jiangnan Basin during a Mid-Permian biotic crisis. The sequence-stratigraphic, petrographic and palaeontologicai record of these sections has been studied and the associated strontium isotopic fluctuations have been assayed. Mass extinction of fusulinid foraminifers is most clearly associated in time with onset of volcanism and a relative sea-level fall that led to the establishment of mid-ramp conditions (Laibin Limestone) in settings that were previously dominated by radiolarian mudstones. The regression also coincides with a low point of [sup.87]Sr/[sup.86]Sr ratios. The lowstand deposits contain mafic scoriaceous grains that record pyroclastic volcanism probably centred in the Emeishan flood basalt province 800 km to the west of Laibin. Thus, unusually violent eruptions associated with flood basalts in this province may have contributed to the environmental stresses responsible for the extinction event. Subsequent environmental changes included transgression, spread of dysoxic waters, indicated by populations of small pyrite framboids, and a major negative C-isotope excursion. All these phenomena have been previously related to the end-Guadalupian extinction but they in fact post-date the crisis because a post-extinction fauna of foraminifers is encountered at this time.

The 260-million-year-old Emeishan volcanic province of southwest China overlies and is interbedded with Middle Permian carbonates that contain a record of the Guadalupian mass extinction. Sections in the region thus provide an opportunity to directly monitor the relative timing of extinction and volcanism within the same locations. These show that the onset of volcanism was marked by both large phreatomagmatic eruptions and extinctions amongst fusulinacean foraminifers and calcareous algae. The temporal coincidence of these two phenomena supports the idea of a cause-and-effect relationship. The crisis predates the onset of a major negative carbon isotope excursion that points to subsequent severe disturbance of the ocean-atmosphere carbon cycle.

The origin of millet from Neolithic China has generally been accepted, but it remains unknown whether common millet (Panicura miliaceum) or foxtail millet (Setaria italica) was the first species domesticated. Nor do we know the timing of their domestication and their routes of dispersal. Here, we report the discovery of husk phytoliths and biomolecular components identifiable solely as common millet from newly excavated storage pits at the Neolithic Cishan site, China, dated to between ca. 10,300 and ca. 8,700 calibrated years before present (cal yr BP). After ca. 8,700 cal yr BP, the grain crops began to contain a small quantity of foxtail millet. Our research reveals that the common millet was the earliest dry farming crop in East Asia, which is probably attributed to its excellent resistance to drought. Holocene | origins of agriculture | phytoliths | Neolithic | Cishan

The 'frozen-in' information in the crust plays an important role in improving our understanding of cratonic formation and evolution and plate tectonics in the Precambrian. The Trans-North China orogen is a continent-continent collision belt generated by the assembly of the North China craton. The mechanism and modality of the collision are disputed. Here we present a seismic image of the Western block and the Trans-North China orogen of the North China craton derived using receiver function analysis of the teleseismic records from a dense array. A low-velocity zone extending from the middle crust to the Moho is interpreted as a remnant of upper-middle crustal material associated with westward-dipping subduction beneath the Western block of the North China craton. Crustal uplift and magmatic underplating resulting from subsequent tectonic events were responsible for modifying the remaining subduction architecture. The western boundary of the Trans-North China orogen is located west of the boundary earlier identified by surface investigation. The results, combined with previous seismic imaging in the eastern North China craton, provide insight into the amalgamation of the Eastern and Western blocks and the subsequent tectonic deformation of the North China craton.

High-resolution [delta][sup.13]C data of organic carbon from a continuous section of the Late Ordovician-Early Silurian reveal two positive [delta][sup.13]C excursions that are associated with the mass extinction in South China. The first stratigraphic [delta][sup.34]S measurements on pyrite tied to well-established biostratigraphy indicate a large perturbation of the sulfur cycle, consistent with major sea-level changes related to the glaciation. The elevated [delta][sup.34]S values of pyrites and a large, short-lived negative [delta][sup.34]S excursion of ~20[per thousand] associated with the decay of the glaciation suggest deep-water anoxia during the Hirnantian Stage, in contrast to the conventional view that the global oceans were oxygenated. We suggest that deep-water anoxia may have contributed to the Late Ordovician mass extinction in South China and possibly elsewhere.

The Yunkai massif is a key region to decipher the tectonic evolution of the south China block since the contained high-grade metamorphic rocks experienced a polyphase deformation. The earliest event ([D.sub.1]) corresponds to a top-to-the-northwest ductile shearing, coeval with amphibolite facies metamorphism, probably developed during a postorogenic synmigmatization extensional event occurred in early Paleozoic time. The main ductile deformation ([D.sub.2]) is top-to-the-northeast shearing, occurred in early Mesozoic time, coeval with amphibolite to greenschist facies metamorphism and associated with the development of northeast verging recumbent folds within the Neoproterozoic-Paleozoic sedimentary cover of the south China block. The tectonic significance of D2 is possibly linked with the subduction of Indochina beneath south China along the Song Ma belt of North Vietnam. Another compressional event ([D.sub.3]) of Late Jurassic to Cretaceous age is indicated by SE verging recumbent folds with NE-SW trending axes developed both in the sedimentary cover and gneissic basement. The northwestward subduction of the Pacific plate or the SE thrusting of the Songpan-Ganzi fold belt upon the Yangtze craton can be considered as the geodynamic causes of this late Mesozoic event. Last, NE SW trending brittle sinistral strike-slip and normal faulting ([D.sub.4]) control the massif uplifting and the subsiding of continental half grabens. This structure, which is widespread in the eastern margin of the Eurasia continent, can be related either to the westward subduction of the Paleo-Pacific plate or to lithosphere removal during the late Mesozoic.

Cratons are old, stable parts of the continental crust that have survived at least since Proterozoic rime and have not undergone strong magmatism or tectonism since their stabilization. Traditionally, the growth of continental crust in the North China craton is considered to have been complete by Paleoproterozoic time, Phanerozoic events being largely restricted to surrounding orogenic belts. However, the eastern part of the North China craton contains large volumes of Mesozoic igneous rocks, with widespread metamorphic core complexes and pull-apart basins. Hf isotope compositions of magmatic zircon grains from igneous rocks in the Liaodong Peninsula indicate that widespread late Mesozoic granitoids formed by partial melting of ancient crust, but with significant input of a mantle component via magma mixing and crustal assimilation. This magmatism has resulted from removal and modification of lithospheric mantle, accompanied by asthenospheric upwelling. The Hf isotopic signatures thus record the addition of juvenile crust beneath the eastern part of the North China craton, which appears related to major extension and possibly slab rollback of the Pacific plate. Whatever the mechanism, it is apparent that since ca. 200 Ma, ancient lithosphere beneath the eastern North China craton has been progressively reactivated and replaced, resulting in 'decratonization.' Tertiary to Holocene volcanism in the area and major subsidence around the Gulf of Bohai suggest that the effects of the process are continuing. Similar processes probably operated in the geological past, leading to significant modification of continental crust and requiring reconsideration of mechanisms for continental breakup and dispersal and of continental growth rates. Keywords: decratonization, Phanerozoic crustal growth, North China craton, zircon, Hf isotope, magmatism.

After the formation of the ~ 260 Ma Emeishan large igneous province, there were two volumetrically minor magmatic pulses at ~ 252 Ma and ~ 242 Ma, respectively. Alkaline mafic dykes intruding both 260 Ma and 252 Ma felsic plutons in the Panxi region, southwestern China, have compositions similar to the Emeishan flood basalts. One dyke is dated using the SHRIMP zircon U-Pb technique at 242 [+ or -] 2 Ma, ~ 18 Ma younger than the start of Emeishan magmatism. The dykes have enriched light rare earth element patterns (La/YbN = 4.4-18.8) and trace element patterns similar to the Emeishan flood basalts and average ocean-island basalts. Some trace element ratios of the dykes (Zr/Nb = 3.8-8.2, La/Nb = 0.4-1.7, Ba/La = 7.5-25.6) are somewhat similar to EM1 source material, however, there are differences. Their end values ([epsilon]Nd = +2.6 and +2.7) and [sub.I]Sr ([sub.I]Sr = 0.704542 and 0.704554) ratios are indicative of a mantle source. Thus Emeishan magmatism may have lasted for almost 20 Ma after the initial eruption. However, geological evidence precludes the possibility that the post-260 Ma magmatic events were directly related to Emeishan magmatism, which began at and ended shortly after 260 Ma. The 252 Ma plutons and 242 Ma dykes represent volumetrically minor melting of the fossil Emeishan plume-head beneath the Yangtze crust. The 252 Ma magmatic event was likely caused by post-flood basalt extension of the Yangtze crust, whereas the 242 Ma event was caused by decompressional melting associated with the collision between the South China and North China blocks during the Middle Triassic. Keywords: Emeishan large igneous province, mafic dykes, Middle Triassic, Late Permian, Middle Permian.

The Gangjia granite stock is a garnet-bearing muscovite leucogranitic body emplaced in Yiwulushan in Western Liaoning Province at the eastern segment of the Yanshan orogenic belt, North China craton. The SHRIMP U-Pb zircon age is 153 [+ or -] 5 Ma. The Gangjia granites are peraluminous with A/CNK of more than 1.14, and exhibit a tetrad effect in their REE distribution patterns, as well as non-charge-and-radius-controlled trace element behaviour. This is in contrast to the LREE-enriched patterns of the host Lushan monzogranites. These geochemical characteristics, together with low Th/U ratios in zircon, suggest that the parental magmas for the Gangjia granites have experienced extensive magmatic differentiation, including interaction between residual melt and a coexisting high-temperature aqueous fluid. Their similar [[epsilon].sub.Nd](t), model ages, compatible age patterns and common volcanic arc signature in source materials between the Gangjia granites and the host Lushan monzogranites indicate their comagmatic relationship. These unusual peraluminous leucogranites, coupled with the voluminous adakitic granites hosting them, represent typical post-orogenic magmatism developed under an intra-continental extensional tectonic regime. At the very end of the prolonged Jurassic magmatic evolution in Western Liaoning, extensive fractionation of most probably ferromagnesian phases and plagioclase from a calc-alkaline magma parental to the host Lushan pluton, with overprint of the magmatic hydrothermal fluid, produced highly evolved peraluminous parental magmas for the Gangjia granites. Keywords: leucogranite, geochemistry, petrogenesis, North China craton.

Chinese loess is regarded as one of the most detailed and complete terrestrial archives of late Cenozoic climate change. However, high-resolution optically stimulated luminescence (OSL) dates presented here reveal that the suborbital chronological framework of Chinese loess used in many previous climate reconstructions requires reassessment. Chronological uncertainty of as much as 10-15 k.y. for the late Pleistocene is largely a result of the widespread use of nonradiometric dating techniques that fail to account for site-specific depositional conditions associated with loess emplacement and diagenesis. OSL-based age models that account for these processes are used to examine detailed records of past sedimentation, as well as grain size and magnetic susceptibility proxies for late Pleistocene East Asian monsoon variation. Abrupt shifts in monsoon proxies occur over [10.sup.2]-[10.sup.3] yr time scales, potentially forced by a variety of factors and influenced by site location and site-specific changes in sedimentation. Keywords: monsoon, luminescence, radiometric dating, Loess Plateau, China, Pleistocene.

Distinctive sedimentary structures, textures, and extremely negative [[delta].sup.13][C.sub.carb] values from the Ediacaran Doushantuo cap carbonate (ca. 635 Ma) in south China were taken as evidence for a methane hydrate destabilization event, but existing data for a methane-derived [[delta].sup.13][C.sub.carb] signature were reported from a single locality in the Yangtze Gorges area. Here we report negative [[delta].sub.13][C.sub.carb] values as low as -48% (Vienna Peedee belemnite) from two additional sections ~6 km and 55 km from the original locality. These negative [[delta].sup.13][C.sub.carb] values were obtained from isopachous cements that fill stromatactis-like cavities, sheet cracks, and fractures, and from partially recrystallized carbonate crusts, consistent with carbonate precipitation at cold methane seeps. The new data support a widespread methane release event following the Nantuo glaciation in south China (ca. 635 Ma), which may have contributed to the origin of unusual sedimentary and isotope features of cap carbonates. Keywords: carbon isotopes, methane seeps, Ediacaran, Doushantuo cap carbonate, south China.

High-grade gneisses of the north Qaidam high-pressure/ultrahigh-pressure metamorphic terrane enclose minor eclogites and ultramafic rocks. In combination with petrological data, sensitive high-resolution ion microprobe U-Pb geochronology on the granulitized gneisses in the Luliangshan and Xitieshan, western north Qaidam Mountains, reveals a polyphase tectonothermal history including Early Neoproterozoic and Early Paleozoic events. The rocks investigated are two granulite-facies paragneisses and one orthogneiss that both surround garnet peridotite in the Luliangshan, and two paragneisses that enclose eclogite in the Xitieshan. The inherited zircon cores from paragneiss and orthogneiss yield ages between ca. 1000 Ma and ca. 2500 Ma, representing Mesoproterozoic to Archaean source material for these gneisses. A ca. 900 Ma age obtained from one orthogneiss and one paragneiss is interpreted as the age of simultaneous Early Neoproterozoic magmatism and metamorphism. This Early Neoproterozoic tectonothermai event is similar in age to the Jinning orogeny, which is commonly recognized in the metamorphic basement of the south China block, and suggests that the north Qaidam Mountains have an affinity to the south China block. Early Paleozoic metamorphism is recorded in all gneiss samples. In conjunction with cathodoluminescence imagery and mineral inclusions, U-Pb dating of zircons reveals two Early Paleozoic age groups: ca. 450 Ma represents the age of high-pressure granulite metamorphism (Grt + Rt inclusions in zircon; kyanite porphyroblasts), whereas ca. 425 Ma reflects the time of medium-pressure, granulite-facies metamorphism (Pl + Sil inclusions in zircon) and associated anatexis during decompression. The ages obtained suggest that the granulitefacies metamorphism lasted for ~25 m.y. and was related to the Early Paleozoic continental collision between the Qilian and Qaidam blocks, and to subsequent thermal relaxation and exhumation. Keywords: polyphase tectonothermal event, gneiss, north Qaidam Mountains, U-Pb geochronology.

The earlier Middle Pleistocene human partial cranium from Hulu Cave, Tangshan, Nanjing (Hulu 1) exhibits an ectocranial lesion which covers most of the anterior neurocranium, largely between the temporal lines and extending from the supratoral sulcus to the anterior parietal bone. The endocranial surfaces and the remainder of the cranium (upper facial skeleton, lateral frontal bone, posterior parietal bones, and mid-occipital bone) are norreal. The healed lesion exhibits both resorption and the lay ing down of new bone. Differential diagnosis suggests that the lesion was caused by either trauma (broad compressive trauma, tensile trauma to the scalp, or partial scalp removal) or burning (with damage to scalp and superficial neurocranium). Dietary deficiencies, infection, and neoplastic disorders do not fit the lesion characteristics. The Hulu 1 specimen therefore joins a growing sample of Pleistocene Homo remains with nonfatal and nontrivial disorders. KEY WORDS Homo erectus; frontal bone; scalp; trauma; burning

[1] New paleomagnetic data from Permian red beds and Middle Jurassic limestones from the Tarim Basin pose a paradox. Their declinations are similar to Upper Carboniferous to Neogene rocks collected from the same sections, and their inclinations parallel present values. When assuming that lower than expected inclinations in continental sedimentary rocks arise from inclination shallowing effects, then the paleolatitudes of all Upper Carboniferous to Present rocks from Tarim are indistinguishable. Local vertical axis block rotations occuring in the last 20 million years explain why declinations vary at different localities in the basin. Our Middle Jurassic data positions Tarim 23.6 [+ or -] 8.4[degrees] farther south than that predicted from the coeval reference pole for Eurasia; however, no geologic argument exists to support the closure of a large ocean basin between Tarim and Siberia since the Middle Jurassic. Thus the paradox: are the rocks from Tarim totally overprinted, or is the middle Mesozoic part of the reference Eurasian apparent polar wander path erroneous? Several lines of evidence suggest the Tarim rocks are not remagnetized. We conclude that Tarim has experienced little of no apparent polar wander since the Carboniferous. Moreover, our Middle Mesozoic reconstruction of Eurasia using the new Middle Jurassic pole from Tarim results in a more geologically compatible solution for the eastern Asian blocks over previous reconstructions. Citation: Gilder, S. A., J. Gomez, Y. Chen, and J.-P. Cogne (2008), A new paleogeographic configuration of the Eurasian landmass resolves a paleomagnetic paradox of the Tarim Basin (China), Tectonics, 27, TC 1012, doi: 10.1029/2007TC002155.

The Shiqiao-Pingshang low-grade metasedimentary rocks sporadically crop out in the Sulu ultrahigh-pressure (UHP) belt in east-central China. Major and trace element data indicate that they were deposited in a passive margin basin, probably located at the southern margin of the North China Craton. Sensitive high-resolution ion microprobe (SHRIMP) U-Pb dating of detrital zircons from a quartzite (SD53) from Pingshang and a quartz schist (SD54) from Shiqiao records ages ranging from 2800 to 1900 Ma. Three age populations are defined: at 2660-2500, 2350-2150 and 2100-1900 Ma, with peak ages at 2522, 2212 and 2020 Ma, respectively. Muscovite Ar-Ar dating of the quartz schist (SD54) yields a plateau age of 265.9 [+ or -] 1.2 Ma. These data support the view that the Shiqiao-Pingshang low-grade metasedimentary rocks originated from the North China Craton, and underwent deformation in the Permian during subduction of the South China Craton (Yangtze block) beneath the North China Craton. This requires that the low-grade metasedimentary rocks were overthrust for several tens of kilometres onto the South China Craton, explaining why source materials from the North China Craton are common in Triassic to Jurassic sedimentary basins adjacent to the Dabie-Sulu orogenic belt.

Horodyskia is one of the earliest known macroscopic life forms, with a fossil record dating from c. 1.4 Ga. Palaeopascichnus represents a key Ediacaran element with world-wide distribution. However, their body constructions and affinities are poorly understood, partly because previously described species are mostly preserved as casts and moulds in siliciclastic rocks. Silicified specimens from the upper Ediacaran Liuchapo Formation in eastern Guizhou, South China, are described as Horodyskia minor sp. nov. and Palaeopascichnus jiumenensis sp. nov. Their taxonomic assignments are based on their uniserial arrangement of spheroidal or discoidal units, which are connected by a filament and surrounded by a quartz halo. They are unlikely to be brown algae, animal traces, faecal pellets, colonial metazoans, or giant sulphide-oxidizing bacteria. Instead, we propose that Horodyskia and Palaeopascichnus may be phylogenetically related, and their collective morphologies allow tentative comparison with agglutinated foraminifers: the segments can be compared with cytoplasm-filled chambers, connecting filament with small passage between chambers, and quartz haloes with agglutinated tests. However, their ontogeny appears to be distinct from that of modern foraminifers. The occurrences of Horodyskia fossils in Mesoproterozoic and Ediacaran rocks indicate an extremely long range (c. 900 Ma) and echoes the proposition of extended evolutionary stasis in the Proterozoic.

[1] Structural and [sup.40]Ar/[sup.39]Ar data from the Yunkaidashan Belt document kinematic and tectonothermal characteristics of early Mesozoic Indosinian orogenesis in the southern part of the South China Block. The Yunkaidashan Belt is tectonically divided from east to west into the Wuchuang-Sihui shear zone, XinyiGaozhou block, and the Fengshan-Qinxi shear zone. Indosinian structural elements ascribed to the Indosinian orogeny include [D.sub.2] and [D.sub.3] deformation. The early [D.sub.2] phase is characterized by folding and thrusting with associated foliation and lineation development, related to NW-SE transpression under amphibolite- to greenschist-facies conditions. This event is heterogeneously overprinted by [D.sub.3] deformation characterized by a gentle-dipping [S.sub.3] foliation, subhorizontally to shallowly plunging [L.sub.3] lineation, some reactived-[D.sub.2] folds and low-angle normal faults. The [D.sub.3] fabrics suggest a sinistral transtensional regime under greenschist-facies metamorphism. The timing of the [D.sub.2] and [D.sub.3] events have been constrained to the early to middle Triassic (~248-220 Ma) and late Triassic (~220-200 Ma) respectively on the basis of [sup.40]Ar/[sup.39]Ar geochronology and regional geological relations. The change from oblique thrusting ([D.sub.2]) to sinistral transtension ([D.sub.3]) may reflect oblique convergence and crustal thickening followed by relaxation of the overthickened crust. In combination with the regional relations from Xuefengshan to Yunkaidashan and on to Wuyishan, the early phase of the Indosinian orogeny constituted a large-scale positive flower structure and is related to the intracontinental convergence during the assembly of Pangea in which the less competent South China Orogen was squeezed between the more competent North China and Indosinian Blocks. doi: 10.1029/2007TC002099.

The Hengshan--Wutai--Fuping belt is located in the middle segment of the Trans-North China Orogen, a Palaeoproterozoic continental collisional belt along which the Eastern and Western blocks amalgamated to form the North China Craton. The belt consists of the medium- to highgrade Hengshan and Fuping gneiss complexes and the intervening low- to medium-grade Wutai granite--greenstone terrane, and most igneous rocks in the belt are calc-alkaline and have affinities to magmatic arcs. Previous tectonic models assumed that the Hengshan and Fuping gneiss assemblages were an older basement to the Wutai supracrustal rocks, but recent studies indicate that the three complexes constitute a single, long-lived Neoarchaean to Palaeoproterozoic magmatic arc where the Wutai Complex represents an upper crustal domain, whereas the Hengshan and Fuping gneisses represent the lower crustal components forming the root of the arc. The earliest arc-related magmatism in the belt occurred at 2560-2520 Ma, marked by the emplacement of the Wutai granitoids, which was followed by arc volcanism at 2530-2515 Ma, forming the Wutai greenstones. Extension driven by widespread arc volcanism led to the development of a back-arc basin or a marginal sea, which divided the belt into the Hengshan--Wutai island arc (Japan-type) and the Fuping relict arc. At 2520-2480 Ma, subduction beneath the Hengshan--Wutai island arc caused partial melting of the lower crust to form the Hengshan tonalitic--trondhjemitic--granodioritic (TTG) suites, whereas eastward-directed subduction of the marginal sea led to the reactivation of the Fuping relict arc, where the Fuping tonalitic-trondhjemitic--granodioritic suite was emplaced. In the period 2360-2000 Ma, sporadic phases of isolated granitoid magmatism occurred in the Hengshan--Wutai--Fuping region, forming 2360 Ma, c. 2250 Ma and 2000-2100 Ma granitoids in the Hengshan Complex, the c. 2100 Ma Wangjiahui and Dawaliang granites in the Wutai Complex, and the 2100-2000 Ma Nanying granitoids in the Fuping Complex. At c. 1920 Ma, the Hengshan--Wutai island arc underwent an extensional event, possibly due to the subduction of an oceanic ridge, leading to the emplacement of pre-tectonic gabbroic dykes that were subsequently metamorphosed, together with their host rocks, to form medium- to high-pressure granulites. At 1880-1820 Ma, the Hengshan--Wutai--Fuping arc system was juxtaposed, intensely deformed and metamorphosed during a major and regionally extensive orogenic event, the Luliang Orogeny, which generated the Trans-North China Orogen through collision of the Eastern and Western blocks. The Hengshan--Wutai--Fuping belt was finally stabilized after emplacement of a marie dyke swarm at 1780-1750 Ma. Keywords: Archaean, Palaeoproterozoic, magmatic arc, subduction, collision, Hengshan--WutaiFuping belt, Trans-North China Orogen.

The Triassic Songpan-Ganzi complex comprises >200,000 [km.sup.2] of 5-15 km thick turbiditic sediments. Although surrounded by several magmatic and orogenic belts, the Triassic high- and ultrahigh-pressure Qinling-Tongbai-Hong'an-Dabie (QTHD) orogen, located several hundred kilometers to the east, was proposed as its major source. Middle to Late Triassic samples from the northern and southern Songpan-Ganzi complex, studied using detrital white mica [sup.40]Ar/[sup.39]Ar ages, Si-in-white mica content, and detrital zircon U/Pb ages, suggest that the northern Songpan-Ganzi deposystem obtained detritus from the north: the north China block, east Kunlun, northern Qaidam, Qilian, and western Qinling; the southern Songpan-Ganzi deposystem was supplied from the northeasterly located Paleozoic QTHD area throughout the Ladinian and received detritus from the Triassic Hong'an-Dabie orogen during the Carnian, indicative of exhumation of the orogen at that time. The QTHD orogen fed the Norian samples in the southeastern southern Songpan-Ganzi deposystem, signifying long drainage channels along the western margin of the south China block. An additional supply from the Emeishan magmatic province and/or the Yidun arc is suggested by the paucity of white mica in the southern Songpan-Ganzi deposystem. Mica ages of Rhaetian sediments from the northwestern Sichuan basin best correlate with those of the Triassic QTHD orogen. Our Si-in-white mica data demonstrate that the high- and ultrahigh-pressure rocks of the Hong'an-Dabie Shan were not exposed in the Middle to Late Triassic. doi:10.1029/2006TC002078.

Two suites of granitoids, the Late Jurassic (158 [+ or -] Ma) Linglong suite and the Early Cretaceous (130-126 Ma) Guojialing suite, crop out in the northwestern Jiaodong Peninsula, eastern China. The Linglong suite is a monzogranite, comprising alkali feldspar, plagioclase, quartz and Ferich biotite. The Guojialing suite includes at least five plutonic bodies of both granodiorite and monzogranite. The rocks are composed of plagioclase, alkali feldspar, quartz, Mg-rich amphibole and Mg-rich biotite. Both the Linglong and Guojialing suites have adakitic affinity. They are enriched in LREE with high La/Yb ratios and show positive Eu anomalies. The rocks are also enriched in LILE and depleted in HFSE with high Sr/Y ratios. The Linglong granite shows very uniform Sr-Nd isotopic compositions with initial [sup.87]Sr/[sup.86]Sr ratios of 0.7119-0.7126 and [[epsilon].sub Nd]end (T) values of -21.3 to -21.6, which are similar to those of the local Neoarchaean basement. The Guojialing suite has variable initial [sup.87]Sr/[sup.86]Sr ratios (0.7108-0.7120) and [[epsilon].sub.Nd] (T) values (-10.8 to -17.2), which are distinct both from those of the Neoarchaean basement and from those of the local enriched lithospheric mantle inferred from the coeval mafic dykes in the studied area. Detailed petrological and geochemical data indicate that the Linglong suite was derived by partial melting of Neoarchaean metamorphic lower-crustal rocks at depth of > 50 km with a eclogite residue, whereas the Guojialing suite was formed by the reaction of delaminated eclogitic crust-derived melt with the upwelling asthenospheric mantle. The petrogenesis of these two contrasting adakitic granitoids suggests intensive lower-crustal delamination during Early Cretaceous times, following a crustal thickening process from the late stage of the Early Jurassic to early stage of the Late Jurassic with crustal thickness of < 32 km to > 50 km, respectively. Keywords: granitoid, adakite, crustal thickening, delamination, Jiaodong Peninsula.

The Gushan diorite pluton, located at the northern margin of the North China block, was emplaced during Middle Devonian times (SHRIMP U-Pb zircon age of 390 [+ or -] 5 Ma). Rocks from the pluton are characterized by low Si[O.sub.2] and high alkali contents, and they show monzodiorite compositions in a total alkali v. silica (TAS) plot. They exhibit light REE-enrichment, no to slightly positive Eu anomalies, strong depletion in Rb, Th, U, Nb, Ta, P, Zr, Hf and Ti, enrichment in Ba, K and Sr, low contents of Y and Yb, and high Sr/Y ratios. They have a relatively narrow range of isotopic compositions with initial [sup.87]Sr/[sup.86]Sr ratios of ~ 0.7050, [[epsilon].sub.Nd](T) values of -9.5 to -7.5 and zircon [[epsilon].sub.Hf](T) values from - 11.8 to -5.8. These features are remarkably similar to another Middle Devonian intrusion, the Shuiquangou syenitic complex at the northern margin of the North China block. These similarities suggest that the two intrusions probably have a common origin. They were considered to be derived from a type I enriched mantle, ultimately with some involvement of ancient lower crustal components, and were likely emplaced in a back-arc extension environment related to southward subduction of the Palaeo-Asian oceanic plate or during the cessation of the subduction. Aluminiumin-hornblende barometry studies of the Middle Devonian Gushan pluton yielded emplacement depths of about 18 km. Combined with previous geobarometry results on the Carboniferous plutons within the Inner Mongolia Palaeo-uplift on the northern margin of the North China block, it is inferred that the uplift and exhumation of the plutons within the Inner Mongolia Palaeo-uplift during Middle Devonian to Late Carboniferous times were not as distinct as those during Late Carboniferous to Early Jurassic times, and the strong uplift and exhumation of the Inner Mongolia Palaeo-uplift were achieved during Late Carboniferous to Early Jurassic times. Keywords: diorite, petrogenesis, Devonian, North China block.

Abstract: Dengjiashan, with 25 Mt at 4.77% Zn, 1.27% Pb, and 14 g/t Ag, is one of the largest SEDEX (sedimentary-exhalative) Zn-Pb sulfide deposits in the western Qinling orogenic belt, [...]