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The southern Junggar Basin, Xinjiang, has abundant coalbed methane (CBM) resources. Currently, the Baiyang River development pilot test area (BYR block for short) in the Fukang east block has achieved large-scale CBM development, but the productivity characteristics and its controlling factor are still unclear. Based on the field production data of the BYR block and experimental tests, this paper summarizes the gas and water production characteristics and presents the analysis results of the geological and geochemical responses to the productivity of CBM wells. The productivity of CBM wells in the BYR block was generally characterized as medium-to-low yield. The productivity was jointly controlled by the burial depth, structure condition, thickness and number of co-production coal seams, and hydrogeological conditions. The gas production first increased and then decreased with the increase in the burial depth of the coal seam, and a burial depth between 750 and 1000 m was the most beneficial to increasing the gas production due to the good gas preservation conditions and suitable permeability and stress conditions. The total thickness of the co-production coal seams had a positive effect on the productivity of gas wells, but the productivity was also affected by the number of co-production coal seams and interlayer interference. In the BYR block, the co-production of the nos. 41 and 42 coal seams was the most favorable combination form for CBM drainage. The productivity of CBM wells had a good response to the Na+, K+ and HCO3− concentrations but a poor response to δD-H2O and δ18O-H2O. Based on the concentrations of the main ions and TDSs of the coal seam water, a productivity response index δ* was established, and there was a good positive correlation between the productivity and δ*. [ABSTRACT FROM AUTHOR]

The reservoir physical properties, pore types, diagenetic characteristics and reservoir quality controlling effect of the Xishanyao formation coal measure sandstone in the southern margin of the Junggar basin were discussed in this study based on thin section observation, high pressure mercury injection, low-temperature nitrogen adsorption and scanning electron microscope observation. The result shows that the porosity and permeability of the sandstone are generally low with a medium-high texture maturity and low compositional maturity. The sandstone storage space is mainly composed of residual intergranular pores, secondary dissolution pores, inter-crystalline pores and micro-fractures. The diagenetic stage of coal measure sandstone is in the mesodiagenesis A1-A2 stage, and their diagenetic interaction types mainly include compaction, cementation and dissolution. The reservoir quality of the coal measure sandstone deteriorates by compaction due to high matrix content and plastic debris content. Because of the large amounts of organic acids generated during the thermal evolution of the coal measure source rock, the coal measure sandstone suffers from strong dissolution. The secondary dissolution pores formed by the massive dissolution of feldspar, lithic fragments and early carbonate cementation in the sandstone significantly improved the reservoir quality. In the coal measure sandstone, clay mineral cementation is the most developed cementation form, followed by quartz cementation and carbonate cementation. Although kaolinite cementation and dolomite cementation can generate a small number of inter-crystalline pores, cementation deteriorates the reservoir quality. The Xishanyao formation coal measure sandstone formed in a lacustrine-delta environment, and its composition and texture make it susceptible to the influence of compaction and dissolution during diagenesis. [ABSTRACT FROM AUTHOR]

The Erlian Basin may be one of the most promising areas for low-rank coalbed methane (CBM) in China. The Cretaceous coal-bearing strata in the Bayanhua sag contain abundant low-rank CBM resources with suitable depths and large coal thicknesses (1.00–78.85 m, avg.22.53 m). However, the research on CBM geology and exploration potential is still lacking, which severely hinders its exploration and development. This paper presents an integrated study of CBM geology in terms of gas reservoir properties, gas-bearing characteristics and controlling factors. The results of the analysis show that lignite and subbituminous coals are the main coal types present in the study area, with medium porosity (7.3–27.8%, avg.20.77%) and low permeability (0.05–21.8 mD, avg.5.54 mD) being dominant. The pores are dominantly transition pores with inkpot shapes, which is beneficial to the adsorption of CBM. The gas content of the coal seams is 1.66–4.45 m3/t and most coal reservoirs are oversaturated. The CBM is primarily of secondary microbial origin, mostly carbon dioxide reduction. The accumulation of CBM is mainly influenced by the structure type, roof lithology and hydrogeology in the study area. According to the integrated analysis of the vertical changes in the physical properties and gas-bearing characteristics, the dominant horizon tends to be the No. 6-7 coal seam, followed by the No. 6-4 coal seam. Based upon the CBM geology and the factors controlling enrichment, the prospecting potential in the Bayanhua sag was appraised, and two favorable areas are proposed for CBM exploitation. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic autoimmune disorder related to abnormal keratinocyte proliferation. Long noncoding RNAs (lncRNAs) are significant regulators in the progression of skin diseases. In this study, we explored how lncRNA MALAT-1 controls the pathogenesis of psoriasis by examining its impact on keratinocyte proliferation, inflammation, and apoptosis. A psoriasis cell model was established by treating HaCaT keratinocytes with the inflammatory factor, IL-22 (100 ng/ml), for 24 h. The MALAT-1 and S100A7 levels in psoriatic lesions, normal skin tissues, and IL-22-stimulated HaCaT cells were determined by RT–qPCR and western blotting. Cell proliferation, inflammation, and apoptosis were detected by the MTT assay, western blotting, and flow cytometry analysis, respectively. Bioinformatics analysis was used to identify the miRNAs that bind to MALAT-1 and S100A7. The relationships between MALAT-1 or miR-330-5p and S100A7 were assessed using a luciferase reporter assay. The MALAT-1 and S100A7 levels were upregulated in both psoriatic lesion samples and IL-22-stimulated HaCaT cells. Silencing MALAT-1 significantly reversed the IL-22-stimulated promotion of HaCaT proliferation and changes in Ki67 and KRT5/14/1/10 protein levels, and MALAT-1 deficiency also reversed the upregulation of TNF-α, IL-17, and IL-23 protein levels as well as suppression of cell apoptosis. As a ceRNA, MALAT-1 competed with S100A7 to prevent miR-330-5p-induced inhibition of S100A7 expression. There was a negative correlation between miR-330-5p and MALAT-1 (or S100A7) expression in psoriatic lesion tissues. In response to IL-22 treatment, miR-330-5p silencing eliminated the effects of MALAT-1 knockdown in HaCaT cells. Thus, these findings demonstrated that MALAT-1 modulates the IL-22-induced changes in HaCaT cells through the miR-330-5p/S100A7 axis. [ABSTRACT FROM AUTHOR]