Jurassic Coalfield Research Articles

Relationship between trace elements and macerals in Huanglong Jurassic coal

ABSTRACTThis study is the detailed publication concerning the origins of trace elements in Huanglong Jurassic coal. Forty-two coal samples were collected from Huanglong Jurassic coalfield. Twenty-two elements, including U, B, F, Hg, Be, Cd, Cr, Cu, Mn, Mo, Ni, Pb, V, Zn, Ba, Co, Ga, Sr, As, Se, Cl, and P, were determined. The element profiles were compared with the organic petrography, and the statistical analysis was also carried out to provide preliminary information for origins of the trace elements. The following conclusions were obtained: Cd, Cr, Cl, Ni, Zn, Co, Ga, Sr, As, Se, and B show inorganic affinity. Hg, V, Be, Cu, Pb, and F show generally vitrinite affinity, suggesting that their origins are associated with parenchymatous and woody tissues of roots, stems, barks, and leaves composed of cellulose and lignin. U shows inertinite affinity, which indicated that wood and leaf tissue weakly altered by decay or by biochemical alteration are the main origins of U. P, Mn, Mo, and Ba show overall mixed affinities, indicating the complex of biological origins.

Hydrochemical characterization and pollution sources identification of groundwater in Salawusu aquifer system of Ordos Basin, China

Ordos Basin is located in an arid and semi-arid region of northwestern China, which is the most important energy source bases in China. Salawusu Formation (Q3 s) is one of the most important aquifer systems of Ordos Basin, which is adjacent to Jurassic coalfield areas. A large-scale exploitation of Jurassic coal resources over ten years results in series of influences to the coal minerals, such as exposed to the oxidation process and dissolution into the groundwater due to the precipitation infiltration. Therefore, how these processes impact groundwater quality is of great concerns. In this paper, the descriptive statistical method, Piper trilinear diagram, ratios of major ions and canonical correspondence analysis are employed to investigate the hydrochemical evolution, determine the possible sources of pollution processes, and assess the controls on groundwater compositions using the monitored data in 2004 and 2014 (before and after large-scale coal mining). Results showed that long-term exploration of coal resources do not result in serious groundwater pollution. The hydrochemical types changed from HCO3−-CO32− facies to SO42−-Cl facies during 10 years. Groundwater hardness, nitrate and sulfate pollution were identified in 2014, which was most likely caused by agricultural activities.

Organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China

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.

Study on Coal’s Green Mining Technology Roadmap of Jurassic Coalfield in Northern Shaanxi

Jurassic coalfield in northern Shaanxi is a typical ecologically fragile area. In recent years, with the rapid development of coal mining industry in this area, the environmental problems were caused by coal mining have become so serious that threat seriously to the sustainable development of northern Shaanxi. In this paper, the research team use multi-round expert seminar to design a coal’s green mining technology roadmap (CGM-TRM) for Jurassic coalfield of northern Shaanxi, which will provide a macro guidance for related government, institutions and enterprises, and produce wide range of utility in relevant R&D activity.

Spatial Feature of Jurassic Sandstone Permeability Based on Pumping Test

In order to plan mining areas, design coal mines in Jurassic coal field, Jurassic sandstone water should be controlled. Spatial feature of Jurassic sandstone permeability should be studied. Pumping test data of a coal mine in Ulugkhemsky coal field in Russia were collected to study spatial feature of Jurassic sandstone on Plane characteristics and vertical characteristics. The result indicates that permeability coefficients near the river and alluvium deposit area are higher than that of normal formation area. Sandstone permeability coefficients decrease with distances to the river increase and buried depths increase. Permeability-Buried Depth fitting equation was established to predict Jurassic permeability coefficients of different depth in normal formation area.