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According to the assumption of "deposition control facies, facies control reservoir", based on field investigation, experimental test and previous research results, a study was performed to investigate the characteristics of shale reservoir controlled by the sedimentary environment of the Lower Cambrian Qiongzhusi Formation in the Middle Lower Yangtze area. The studies show that the organic-rich shale is mainly developed in the shelf facies and deep-sea retention basin facies, the thickness of deposition center is up to 100-180 m with the maximum organic carbon content of 18.7%, and the average organic carbon content is 5.07%. The major lithologies include organic-rich carboniferous shale, siliceous shale, silty shale and calcareous shale under anoxic environment. The minerals of the shale are mainly quartz (average 64.97%) and clays (average 23.66%). A large number of intergranular holes of pyrite under the anoxic environment, microporosity produced by hydrocarbon generation in organic matter, microporosity between layers of clay minerals and micro-cracks controlled by brittle mineral provide a good reservoir space for shale gas. Therefore, the studies on the development of reservoir characteristics under the control of the environment will provide a substantial basis for shale distribution, organic matter abundance, reservoir space and favorable area evaluation in shale gas exploration and development. [ABSTRACT FROM AUTHOR]

The anchorage performances, mixing uniformity of resin anchoring agent, setting torque and thrust of the current five kinds of resin anchoring holts with different rod shapes in coal mine roadways were studied by laboratory tests. The results show that the pulling force of five kinds of bolts is more than 170 kN under the condition of 125 mm anchor length. The mixing effect is poor with finish rolling right-handed all-coarse-thread bolts, a large area of anchorage segmenl are empty or rod and resin anchoring agent separated. Left-handed no longitudinal fine rib bolts have the minimum setting torque, the setting torques of finish rolling right-handed all-coarse-thread bolts, left-handed low wide rib bolts, finish rolling right-handed all-fine-thread bolts, general left-handed no longitudinal rib bolts are respectively 1.75 times, 1.85 limes, 2.7 times and 2.5 times of its. Finish rolling right-handed all-coarse-thread bolts and finish rolling right-handed all-fine-thread bolts need one or two workers to complete the installation in the case of full length anchorage. age. Left-handed low wide rib bolts needs two or three workers, and general left-handed no longitudinal rib bolts and lefthanded no longitudinal fine rib bolts need three or four workers to complete the installation. Although left-handed low wide rib bolts is obviously better than general left-handed no longitudinal rib bolts on the anchorage and installation performance, but there are still spaces for optimization, especially in the areas of cross rib width and height. [ABSTRACT FROM AUTHOR]

Given ordinary polyurethane grouting reinforced materials releases amount of heat when curing reaction happens, it will cause fuming or catching fire when applying in underground coal mine, so a kind of novel self-controlling temperature polyurethane (SCT-PU) grouting materials, which with Na2Si03 and NaCl aqueous solution as self-limiting additives and blending with polyether polyol as white material, with isocyanate as a black material, was prepared. Its composition, structure, properties and self-limiting temperature heat storage mechanism was studied. The results show that,maximum storage temperature of self-limiting polyurethane grouting material is 101.5 °C, significantly lower. There are many sections of grouting material foam, hole contains solid microspheres, there is an annular gap between the two. Na2Si03 in Self-limiting additives absorp C02 producting in the reaction of isocyanate and water, generated Si (OH) 4 microspheres. Si(OH) 4 endothermic dehydration is the main reason of the system to limit temperature increase. Water present in the annular gap vaporization is the final barrier of the system to limit the heat rise. Combination properties testing and mine grouting industrial experiment show that the production properties reach or exceed coal national industry standard of polyurethane grouting reinforced materials, especially have outstanding advantages in stored temperature. [ABSTRACT FROM AUTHOR]

Concrete was used to simulate the real rock. The effects of bolt prestress on the shear behavior of jointed rock mass were studied with the approach of joints directly shearing in laboratory and situ. The results show that as the prestress improved, the initial shear stiffness of the rock mass is improved, playing an important role in inhibiting the early deformation of the surrounding rock and improving the performance of bolt supporting; As the prestress increased, the jointed rockmass presented phased characteristics, including three stages, such as rapidly increasing resistance, slowly increasing resistance and resistance reduction characteristics; Situ tests show that bolt resistance could be enhanced when the bolt prestress improved and highly-pre-stressed fully-encapsulated rock bolts achieved good results for jointed rock supporting. [ABSTRACT FROM AUTHOR]

Focused on the Lower Cambrian Qiongzhusi formation shale outcrops investigation, sampling and laboratory analysis in middle and upper Yangtze region. Studies show that the Lower Cambrian has thick black shale (50-400 m), excessive organic carbon content (the average is 1. 92%-2. 35% ) ,a high degree of thermal evolution (the average is 2. 0%-4. 0%), a formation with good potential shale gas resources. According to analysis the distribution character of shale thickness-, organic carbon content, maturity, mineral composition, pore and gas-bearing in the research area, optimized three shale gas exploration potential areas; southern Sichuan-western Guizhou, Micangshan-Daba Mountain foreland and western Hubei-eastern Chongqing-northern Guizhou, and evaluated shale gas potential resource in each area. [ABSTRACT FROM AUTHOR]