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Myocardial ischemia/reperfusion (MI/R) injury still remains a great challenge in clinical therapy. The dual-specificity phosphatase 6 (DUSP6) is a protein phosphatase that regulates various physiological and pathological processes through mediating mitogen-activated protein kinase (MAPK). However, the effects of DUSP6 on MI/R are unknown. Here, we found that DUSP6 expression levels were markedly increased in hearts of mice with MI/R operation compared with the Sham group, which were validated in hypoxic/reoxygenation (H/R)-treated primary cardiomyocytes. Our results then showed that adeno-associated virus serum type 9 (AAV9)-regulated DUSP6 over-expression significantly reduced the infarct areas in mice with MI/R treatment, along with ameliorated cardiac injury and dysfunction. Additionally, mitochondrial impair, apoptosis and oxidative stress in MI/R mice were also considerably mitigated by AAV-DUSP6, which were verified in H/R-treated cardiomyocytes with DUSP6 knockdown. Furthermore, western blotting results indicated that MI/R- and H/R-stimulated activation of ERK1/2 in hearts and cardiomyocytes, respectively, were dramatically decreased by DUSP6 over-expression. Notably, we found that DUSP6 knockdown significantly accelerated H/R-induced cell death, reactive oxygen species (ROS) generation, mitochondrial impairment and phosphorylation of ERK1/2; however, these effects were almost abrogated when ERK1/2 activity was blocked by the treatment of its selective inhibitor BVD-523, suggesting that ERK1/2 signal might be necessary for DUSP6 to perform its regulatory role. Collectively, all our results revealed that DUSP6 exerted protective effects against MI/R damage by repressing ERK1/2 activation, and thus may be a promising therapeutic candidate for the treatment of the disease.

The multi-stage hydrocarbon charge process of Kela-2 gas field in the Kuqa foreland basin was studied from the perspective of palaeo-fluid evidence by the analyses of fluid inclusions, fluorescence spectroscopy, FE-SEM (field emission scanning electron microscopy) observation, core micro-CT scanning, and hydrocarbon geochemistry. The result shows that the Kela-2 gas field has experienced three periods of hydrocarbon charge process: (1) charged with oil at the early-middle period of the Miocence (N1), (2) charged with high maturity oil & gas at the sedimentary period of the Pliocence Kuqa Formation (N2) and then destroyed by intense tectonic compression, and (3) charged with high- and over-maturity coal-derived gas since the Quaternary. The widely distributed residual dry bitumen, the occurrence of gas-liquid two-phase hydrocarbon inclusions, the residual oils observed in the nanopores, the higher QGF and QGF-E index, and the higher S1, S2 values of rock pyrolysis detected in both current gas zone and water zone, are the evidence of early oil charges. The residual dry bitumen, the occurrence of gas-oil-solid (bitumen) three-phase hydrocarbon inclusions, the loss of light n-alkanes and the relatively high content of aromatic hydrocarbons in the condense oil, and the abnormally high content of diamondoid hydrocarbons, are the strong evidence of gas flushing and deasphalting. Key words: palaeo-fluid, fluid inclusions, charge history, gas flushing, Kela-2 gas field

Dominant factors controlling hydrocarbon distribution are analyzed from three aspects: the types, structural units and structural belts of the foreland basins of central and western China. There are four types of foreland basins recognized in China, superimposed, reformed, presenile, and newly-generated foreland basins. Hydrocarbon distribution is different in the four types of basins and is controlled by their respective hydrocarbon accumulation conditions, characteristics and patterns. Thrust belts, foredeeps, slope belts, uplift belts, and other structural units are developed in foreland basins. The different controls of these structural units on source rock development and evolution, trap type, hydrocarbon accumulation process, and preservation condition, cause different characteristics of hydrocarbon distribution in different structural belts. The main hydrocarbon enriched structural units are foreland thrust belts, in which the structural styles, tectonic evolution and the preservation of regional cap-rock are the critical factors for hydrocarbon accumulation. The configuration of faults and cap rocks in thrust belts determines the features and enrichment regularity of hydrocarbon and indicates hydrocarbon enriched locations and favorable exploration targets in various structural belts. Key words: foreland basin, structural unit, thrust belt, hydrocarbon distribution, controlling factors

Three potential exploration fields of the Southern Junggar Basin are proposed and discussed through seismic structural interpretation and three-dimensional geological modeling based on quantitative structural analysis techniques. The first field comprises Tertiary imbricate wedges in the core of the second anticlinal belt. These small-scale wedges contribute to different properties of oil, gas and water in different parts of the same anticline. The second field consists of deep Mesozoic structures of the Jurassic-Cretaceous fault-bend folds, which are different in sequences and levels from the overlying Tertiary wedges. The third field is composed of the lateral transfer structures mainly in the second anticlinal belt, which are formed by transfer action between adjacent anticlines. Identification of the above three structural types must be based on pertinent seismic deployment and imagery processing. For the exploration of deep structures, a three-dimensional medium model, in which shear module, Lame's constants and density are specified to truly represent mechanical properties of the rock units, must be constructed first to calculate the restoration strains within the model by using the volumetric restoration technique. The strain data can help predict the fracture azimuth, density and intensity of deep reservoirs. Key words: structural wedge, deep structure, transfer zone, restoration strain, Southern Junggar Basin

Foreland basin represents one of the most important hydrocarbon habitats in central and western China. To distinguish these foreland basins regionally, and according to the need of petroleum exploration and favorable exploration areas, the foreland basins in central and western China can be divided into three structural types: superimposed, retrogressive and reformative foreland basin (or thrust belt), each with distinctive petroleum system characteristics in their petroleum system components (such as the source rock, reservoir rock, caprock, time of oil and gas accumulation, the remolding of oil/gas reservoir after accumulation, and the favorable exploration area, etc.). The superimposed type foreland basins, as exemplified by the Kuqa Depression of the Tarim Basin, characterized by two stages of early and late foreland basin development, typically contain at least two hydrocarbon source beds, one deposited in the early foreland development and another in the later fault-trough lake stage. Hydrocarbon accumulations in this type of foreland basin often occur in multiple stages of the basin development, though most of the highly productive pools were formed during the late stage of hydrocarbon migration and entrapment (Himalayan period). This is in sharp contrast to the retrogressive foreland basins (only developing foreland basin during the Permian to Triassic) such as the western Sichuan Basin, where prolific hydrocarbon source rocks are associated with sediments deposited during the early stages of the foreland basin development. As a result, hydrocarbon accumulations in retrogressive foreland basins occur mainly in the early stage of basin evolution. The reformative foreland basins (only developing foreland basin during the Himalayan period) such as the northern Qaidam Basin, in contrast, contain organic-rich, lacustrine source rocks deposited only in fault-trough lake basins occurring prior to the reformative foreland development during the late Cenozoic, with hydrocarbon accumulations taking place relatively late (Himalayan period). Therefore, the ultimate hydrocarbon potentials in the three types of foreland basins are largely determined by the extent of spatial and temporal matching among the thrust belts, hydrocarbon source kitchens, and regional and local caprocks.

As proved by the analysis of growth strata and regional study, the intense tectonism of the Cenozoic in the northern margin of Tianshan Orogenic Belt initiated at about 10–7 Ma BP and associated with intense tectonic deformation, led to the formation of three thrust belts at the northern margin of Tianshan Orogenic Belt. The time of intense deformation is much younger than that of the southern Tianshan, which suggests that the tectonic deformation propagated from the southern Tianshan to the northern Tianshan due to the India-Asia collision. The intense deformation of the Late Cenozoic resulted in relatively gentle deformation in the western Uromuqi-Qigu anticline and widespread tectonic deformation transporting and retrogressing from the south to the north. The differential tectonic deformation indicates that the front of thrust belt is beneficial to hydrocarbon accumulating. Moreover, for the intense denudation and uplifting along the structure belt of foreland, structures with gentle deformation are advantageous to the preservation of oil and gas accumulating during the early phase.