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The coal-bearing strata of Longdong mine field in Xingtai is the Carboniferous-Permian. The No.8 coal seam is located in the Taiyuan formation and is the main minable coal-bed. The coal is mainly gas-fat coal accompanied with coking coal, lean coal and anthracite. The results of the macroanalysis and maceral quantitative analysis on the main minable coal-bed show that the degree of coal metamorphism takes the old town as the center and is distributed concentrically outward and the anthracite and lean coal are distributed nearby the old town, and the coal gradually becomes coking coal, gas-fat coal and gas coal further outwards. The degree of coal metamorphism was affected by regional metamorphism, and the coal seams which are close to the old town stack the regional magmatic thermal metamorphism. The conclusions of the research offer a scientific foundation to exploit the coal resource in this area?

This study aims to clarify the evolution law of stress field and fracture field during the mining process of inclined coal seam, to prevent the occurrence of roof burst water and impact ground pressure accident during the advancing process of working face.

The evolution law of stress-fracture field under different mining conditions of inclined coal seam was studied by using discrete element method and similar material simulation method.

The overburden stress at the lower end of the coal seam was mainly transmitted to the deep rock mass on the left side, and the overburden stress at the upper end was mainly transmitted to the floor direction. With the increase of the inclined length of the mining coal seam, the development of the fracture zone gradually evolves from the “irregular arch” form to the “transversely developed trapezoid” form. The development range of the fracture zone was always in the internal area of the stress concentration shell.

An original element of this paper is based on the condition that the dip angle of coal seam is 35°, and the evolution law of overburden stress-fracture field during the excavation of coal seam with different lengths was analyzed by UDEC numerical simulation software. The coupling relationship between stress shell and fracture field was proposed, and the development range of fracture zone was determined by stress. The value of this paper is to provide technical support and practical basis for the safety production of a mine working face.

The purpose of this paper is to establish a strain prediction model of mining overburden deformation, to predict the strain in the subsequent mining stage. In this way, the mining area can be divided into zones with different degrees of risk, and the prevention measures can be taken for the areas predicted to have large deformation.

A similar-material model was built by geological and mining conditions of Zhangzhuang Coal Mine. The evolution characteristics of overburden strain were studied by using the distributed optical fiber sensing (DOFS) technology and the predictive model about overburden deformation was established by applying machine learning. The modeling method of the predictive model based on the similar-material model test was summarized. Finally, this method was applied to engineering.

The strain value predicted by the proposed model was compared with the actual measured value and the accuracy is as high as 97%, which proves that it is feasible to combine DOFS technology with machine learning and introduce it into overburden deformation prediction. When this method was applied to engineering, it also showed good performance.

This paper helps to promote the application of machine learning in the geosciences and mining engineering. It provides a new way to solve similar problems.

This study aims to investigate the compositional characteristics of aromatic hydrocarbons extracted from coals and to describe how the sulfur content influences the properties of coals and whether widely accepted maturity parameters are suitable for medium- to high-sulfur coal.

Four samples of medium- to high-sulfur coal were obtained from Fenxi, Shanxi Province, and studied using gas chromatography and gas chromatography–mass spectrometry (GC-MS).

The GC-MS results showed that there were five series of compounds were identified in the aromatic fractions: naphthalenes, phenanthrenes, oxygen-containing compounds, biphenyls and sulfur-containing compounds. The substituent group was mainly methyl. The content of dibenzothiophenes was high, which was attributed to their high thermodynamic stability. The presence of sulfur reduced the content of oxygen-containing compounds. A depositional environment that facilitated the formation of organic sulfur compounds led to a higher content of naphthalenes.

The development of methods for removing organic sulfur compounds would benefit from a study of their nature, which would be important for improving the use of coal.

The purpose of this paper is to take the early Permian no.6 coal seam in Jungar coalfield of North China as an example, this paper studied the net primary productivity (NPP) level of the early Permian peatland and its relationship with the atmospheric environment at that time, analyzed the influence of the atmospheric environment, and discussed its control factors.

First, geophysical logging signals were used for a spectrum analysis to obtain the Milankovitch cycle parameters in the no. 6 coal seam, including the eccentricity (95 ka); obliquity (35.6 ka); and precession (21.2 ka). These were then used to calculate the accumulation rate of the residual carbon in the no. 6 coal seam, which was determined to be between 49.44 and 50.57 gC/(m² · a). The carbon loss could be calculated according to the density and residual carbon content of the no. 6 coal seam. Then, the total carbon accumulation rate of the peatland was further derived as being between 64.91 and 66.40 gC/(m² · a). Also, the NPP of the peatland was determined to be between 129.82 and 132.8 gC/(m² · a).

The result showed that the NPP of the early Permian peatland area was lower than that of the Holocene at the same latitude, and also lower than that of the later Permian of South China.

This study’s comprehensive analysis indicated that the temperature and humidity conditions, along with the oxygen and carbon dioxide levels in the atmosphere, were the main control factors of the NPP of the early Permian peatland. Also, wildfires were found to play a role.

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.

It is recognised by valuers that the effects of coal mining on land in Great Britain can have a significant impact oon the value of a particular site when it is being considered for potential surface development purposes. In this respect a great many buildings are erected successfully each year within mining areas after the effects of mining have been taken into account. If, however, the adverse effects of mining are not recognised and during the site development stage a problem suddenly appears, it is obvious that this may lead to considerable increases in cost and/or delay to the proposed development for which the land was originally purchased. Obviously with sufficient prior appreciation and investigation of the mining position such situations could be avoided. It is with this in mind that the following paper aims to indicate in broad outline, but in such detail relevant to the valuer, some of the major influences of coal mining which require to be recognised and equated in monetary terms when assessing potential site values for development purposes in mining areas.

Discuss in detail the uses which might legitimately be made of the following passage by the writer of a profound study of economic life and thought in France at the end of the reign of Louis XIV. In answering the question make full use of your knowledge of (a) historical criticism; (b) French economic and general history.

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