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The Aksu Proterozoic blueschist terrane in northwestern China is regarded as one of the oldest well-substantiated Precambrian blueschist terranes in the world. Previous work has focused on the high-pressure metamorphism: both the age and P--T conditions of the metamorphic event have been well discussed. However, little attention has been paid to protolith identification of the blueschist terrane. In this paper, we present geochemical and Sr--Nd analyses of metabasalt samples from the blueschist terrane. The results show that the protoliths of these marie schists were enriched mid-ocean ridge basalt (E-MORB). Crystal fractionation has led to differentiation of trace element concentrations. This provides the opportunity to obtain a protolith Sm--Nd isochron age of 890 [+ or -] 23 Ma (MSWD = 0.68). We conclude that the Aksu blueschist terrane represents part of an ocean crust at the NW edge of Rodinia around Tarim at c. 890 Ma. It experienced subduction and exhumation followed by accretion to the Tarim craton. If the north margin of present Tarim faced outboard of Rodinia during subduction, it might form one section of the arcuate subduetion zone around the supercontinent. Alternatively, the subduction zone may have been located between Tarim and Australia and would later be closed. doi: 10.1144/0016-76492010-001.

The widely exposed Kuluketage diabase dyke swarm, Tarim Block, NW China, has been considered to have been emplaced in Permian times. New precise zircon U-Pb SHRIMP ages for two samples from the dyke swarm yield Neoproterozoic ages of 823.8[+ or -]8.7 Ma and 776.8[+ or -]8.9 Ma. Correlated with peaks of magmatism in South China and Australia at c. 825 Ma and c. 780 Ma, these two new ages provide significant information for palaeocontinental reconstructions. The prolonged duration of the magmatic events, combined with regional stratigraphic relationships, imply that the Tarim Block may have been affected by a mantle plume during the breakup of Rodinia. Keywords: Tarim, dyke swarm, Neoproterozoic, Rodinia.

The Junggar Basin is a large superimposed basin with multistage evolution. The Carboniferous volcanic rock in the middle‐lower part of the basin has been an important target of oil and gas exploration. Therefore, it is crucial to establish a set of efficient methods and techniques to find out the distribution of the Carboniferous volcanic rock and the tectonic factors related to the reservoir forming of the volcanic rock. Our research reveals that the density and magnetism of the Carboniferous volcanic rock are obviously higher than those of the Mesozoic and Cenozoic sedimentary rocks. With a series of frequency domain filters and boundary enhancement techniques, we determine the residual gravitational and magnetic anomalies caused by the Carboniferous volcanic rock. Combined with borehole and seismic data from the studied areas, the horizontal and vertical distributions of the Carboniferous volcanic rock are defined, and the lithologies of different types of volcanic rocks are predicted. Furthermore, the gravitational and magnetic anomalies are used to estimate the basement faults and topography. The regional deep faults and their secondary faults of the basement are outlined, and the model of basement relief is constructed. Finally, the effects of the fracture structure and the basement topography in the process of volcanic activity and hydrocarbon accumulation are fully discussed. These results provide fundamental information for optimal selection of the favorable area of volcanic reservoir. [ABSTRACT FROM AUTHOR]

Seventeen new 40Ar/39Ar analyses reported for ten Tarim Precambrian basement samples from the Kuluketage area, are applied to reconstruct the regional thermo-tectonic history together with previously published data. Eight samples were taken adjacent to the Xingdi and Xinger faults, major structures in the study area, whereas a further two were sampled at some distance from the faults. 40Ar/39Ar data from the latter record rapid cooling following a Neoproterozoic magmatic/metamorphic event and mild Paleozoic thermal disturbance. Paleozoic 40Ar/39Ar ages from the study area, as well as from the Central Tianshan and eastern Southern Tianshan suggest two strong deformational periods at ∼390 Ma and ∼300 Ma. During the older period, argon isotopic systems were reset/disturbed by high temperature related to arc magmatism resulting from subduction of the South Tianshan paleo-oceanic crust, possibly in combination with reactivation of Precambrian faults. The younger period is characterized by widespread late Carboniferous-early Permian intracontinental deformation, which is related to the final amalgamation of the Central Asian Orogenic Belt. Previously published apatite fission track data attest to a long history of post-collisional cooling, which is attributed to continued propagation of deformation within the Central Asian Orogenic Belt. [ABSTRACT FROM AUTHOR]

The article discusses the diagnosis and treatment of two types of mountain sickness, called high-altitude pulmonary edema (HAPE) and high-altitude cerebral edema (HACE), by individuals traveling to China's Tibet high-altitude region. Topics include the authors' analysis of the efficacy of early-stage diagnosis of HAPE and HACE, the evaluation of several treatment regimens based on major medications used in clinical practice, and the development of standardized treatment of HAPE and HACE.

The article discuss research investigating erythrocyte (red blood cell) immune function and gastrointestinal mucosa barrier function following the rapid ascent to high altitude (HA). The results of a study monitoring and analyzing erythrocyte C3b receptor rosette (E-C3bRR) and erythrocyte immune complex rosette (E-ICR) levels and evidence that rapid ascent to HA causes impairment in gastrointestinal mucosa barrier function are presented.

The article discusses an epidemiological study of acute mountain sickness (AMS) China's Tibetan Plateau and its systematic prevention. Topics include the challenges for the prevention, on-site rescue, and clinical treatment of AMS presented by environmental hypoxic (low oxygen) conditions, risk factors for AMS, such as overwork, extreme cold temperature, and cardiopulmonary diseases, and the five aspects of the concept of systematic prevention.

The article discusses the challenges of performing heart surgery on the Tibetan Plateau. The authors argue that it is possible to perform successful cardiac surgery at high altitude (HA) in a low oxygen (hypoxic) environment and discuss their experience of performing cardiac surgeries on the Tibetan plateau since late 2000 under various environmental conditions, including surgeries for atrial septal defects, ventricular septal defects, and valvular heart disease.