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A detailed analytical study of Leping bark liptobiolith in Jiangxi was conducted to determine its petrographic characteristics and depositional environment based on coal petrography and geochemistry. Results indicate that barkinite mainly occurs in the middle and lower coal sea4ms, whereas less barkinite and more vitrinite occur in the middle and upper coal seams. Coal facies analysis of bark liptobiolith was performed to determine its characteristics under various depositional conditions, such as the presence of a water table and gelification during coal formation. Results indicate that the environmental evolution of bark liptobiolith begins from brackish-marine swamp facies (barkinite-rich coal seam) and ends in back barrier swamp facies (barkinite-poor coal seam).

Twenty-two coal samples and eleven parting samples were taken from Gashun Coal Mine, Hoxtolgay coalfield, Xingjiang Autonomous Region, and the samples were analyzed by using optical microscopy. The results indicate that the dominant macerals are vitrinite (av. 76.6%) with minor amounts of inertinite (av. 18.84%) and low liptinite (av. 2.7%), along with low content of mineral matters (av. 1.86%). All GI, TPI, VI, GWI values and two facies diagrams indicate that the main coal facies are in limnic area. Meanwhile, the overall petrographic composition and coal facies types indicate that the coal formed in strong wet reducing peat accumulating conditions which were the lacustrine marshes.

Based on core description, gas logging and laboratory analysis, this paper aims to study the controlling effect of the types of shale sedimentary microfacies in coal formations over shale reservoirs using the example of Shanxi formation in Northern Ordos Basin.

According to core observation, the authors selected typical samples of rock types for thin section analysis to determine the micro features and compositions of rocks.

By using core observation, we found that fine lithology in Shanxi formation included major shale, carbonaceous shale, partially carbonaceous shale, partially silty shale and silty shale with colors of gray, dark gray, black and/or gray. Shanxi Formation shale are deposited in plant-rich and plant-poor swamps, interdistributary depressions of delta plains, interfluvial depressions of meandering rivers as well as microfacies environment of natural levees and the distal crevasse splay.

Currently, the research on the shale gas in Shanxi Formation in the Ordos Basin is still in its infancy. There is yet no research on the fine-grained partition of the sedimentary facies in coal accumulation environment of Shanxi formation and the controlling effect of sedimentary microfacies over shale reservoirs.

In this paper, the geochemical characteristics of the trace elements of the No. 6 coal seam from Tanggongta mine, Jungar Coalfield, were studied using the methods of an energydispersive X-ray spectrometer (SEM-EDX) analysis, X-ray powder diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence spectrometric (XRF) techniques. The content of sulfur ranges from 0.09% to 2.83% (1.09% on average). The ash is from 11.70% to 31.47% (20.72% on average), and the moisture is from 2.72% to 6.82% (4.72% on average). The main minerals are kaolinite, carbonate minerals and pyrite. Compared with the average values of Chinese coal, the contents of Ga, Cd, Tl, Li, Sr, and Ag are high. Compared with the values of world coal, Li and Sr are found at high levels. The distribution mode of the REE shows that LREE is concentrated, but HREE is relatively low. The Yinshan Oldland should be the most likely source of the coal’s Li. The bauxite of the Benxi formation could be another source of the coal’s Li in the NE Jungar Coalfield.

A total of 283 coal and parting samples were taken from the Pingshuo mine district, Ningwu coalfield, China. The contents, distribution and enrichment mechanism of 12 hazardous trace elements were studied. The results indicate that Co, Ni, Zn, Cu, Ag and Cr have the chalcophile affinity; Ba, Cd, U are related with clay mineral; Mn is mainly related with carbonate minerals; Pb and Be may be related with sulfide, clay mineral and organic matter. Most of trace elements were associated with terrigenous clastic and clay. The elements (Cr, Pb, Be, Ag, Cu, U, Cd) were enriched in the wet forest and low swamps.

This paper describes the organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China. A total of 18 bench samples were taken from Huangling Mine 2. The average content of barium (3701 mg/kg) was about 23 times higher than that of common world coals. Terrestrial higher plants were the main coal-forming parent material. Relying on the parameters of OEP, Pr/Ph and so on, there is little correlation between organic geochemical characteristics and barium enrichment. Therefore, organic material has little influence on the process of coal-forming and the enrichment of barium.

This paper aims to take the four resin as adsorbent and coal ash alkaline solution as the material and use the single factor experimental method to study absorption influence factors for each resin to absorb lithium. At the same time, the authors got the special properties of some kinds of resin and compared the test results of each resin at the optimum factors.

Because many factors affect the test, this study uses the method of comparison and control variables. This method study on the influencing factors of ion exchange resin adsorption Li⁺.

In these adsorption experiments, the basic resin adsorption effect is more obvious. The optimum adsorption conditions are as follows: resin quality is 0.1 g, the volume of fly ash solution is 100 ml, magnetic stirrer speed is 140 r/min and the adsorption time is 60 min. Under these conditions, the adsorption rate of Li⁺ could reach 25.17 per cent aluminum.

Li extracted from coal ash can not only relieve the lithium resources in short supply but can also provide a new mode to the field of coal resources in recycling economy and transition economy. At the same time, the extraction of Li resources will provide an important reserve of raw materials for the future of nuclear power plant.

The purpose of this paper is to find the relationship of palaeontology, palaeobotany and coal thickness of Taiyuan Formation during Late Carboniferous – Early Permian Period in Shanxi Province.

This paper selects three regions, namely, Baode, Xishan and Lingchuan, to analyse the distribution characteristics of palaeontology, palaeobotany and variation of coal thickness.

It was found that in a certain period of geological history, palaeontology and palaeobotany play a dominant role in shaping of a coal-bearing basin. Coal seam thickness changes largely from the northwest to the southeast, gradually thinning in Taiyuan Formation.

Palaeontology and palaeobotany play a dominant role in the shaping of a coal-bearing basin.

Sedimentary facies type of the Shanxi Formation in northeastern Ordos Basin is an ongoing debate. Based on field measurements, sample collection and identification, and laboratory analysis, we systematically evaluated the sedimentary characteristics of the sandstone bodies of Shanxi Formation of Chengjiazhuang section in Liulin. Analysis included identifying sample composition, grain size, texture, sedimentary structure and spatial distribution. We came to the conclusion that the sedimentary environment of Shanxi Formation is deltaic. This deltaic environment included deltaic front and deltaic plain. It can be further divided into five sedimentary microfacies: subfluvial distributary channel, subfluvial distributary interchannel, distributary channel, levee, and peat bog. And lastly, the evolution of sedimentary environment of Shanxi Formation is discussed.

Lithofacies and their relationships, textural content, sedimentary structures were used to delineate eight facies associations in the Benin west-1. Seven lithofacies are recognized; coarse grained sandstone with granules, laminated shaley sandstone, shaley siltstone, laminated shaley siltstone with fossil fragment, laminated shale, siltstone, coarse grained sandstone and micaceous sandstone facies. Each lithofacies is interpreted to represent different or similar depositional environments. Sediments of the Ameki Formation and Imo Shale encountered in the Benin west-1 were deposited in distributary channel and prodelta to marine shelf environments