Molecular Organic Geochemical Characteristics and Coal Gas Potential Evaluation of Mesozoic Coal Seams in the Western Great Khingan Mountains

2020 ◽  
Vol 94 (2) ◽  
pp. 409-417
Author(s):  
Yue QU ◽  
Xuanlong SHAN ◽  
Tiantian DU ◽  
Xianli DU ◽  
Rongsheng ZHAO
Keyword(s):  
Geochemical Characteristics ◽  
Coal Seams ◽  
Coal Gas ◽  
Potential Evaluation ◽  
Gas Potential ◽  
Great Khingan Mountains

Lithological-geochemical characteristics of natural outcrops of the Domani sediments in the areas of the Pre-Urals regional trough of the Volga-Ural oil and gas basin

2019 ◽  
pp. 28-33
Author(s):  
K. A. Radchenko ◽  
N. I. Korobova ◽  
M. A. Bolshakova ◽  
A. V. Stoupakova ◽  
A. P. Zavyalova ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Geochemical Characteristics ◽  
Carbon Formation ◽  
High Carbon ◽  
Oil Reserves ◽  
Siliceous Rocks ◽  
Exploration And Production ◽  
Domanik Formation ◽  
Lithological Composition ◽  
Gas Potential

Replenishment of oil reserves requires searching, exploration and production of new unconventional objects. Among these objects is Domanik formation, which is widespread in the Volga-Ural basin. The Domanic high-carbon formation is presented by thin-layered carbonate-siliceous rocks with a high content of organic matter, capable of both producing hydrocarbons with its own oil and gas potential, and concentraring them in reservoirs [Stupakova et al., 2017]. Study of lithological composition of rocks help to obtain information about the nature of hydrocarbon accumulations and understand possibilities of estracting hydrocarbon of them. The lithological and geochemical characteristics of rocks are an integral part of the study such types of deposits.

The differences of element geochemical characteristics of the main coal seams in the Ningdong coalfield, Ordos Basin

2019 ◽  
Vol 202 ◽  
pp. 77-91 ◽  
Author(s):  
Liu Zhifei ◽  
Wei Yingchun ◽  
Ning Shuzheng ◽  
Jia Xu ◽  
Qin Rongfang ◽  
...  
Keyword(s):  
Ordos Basin ◽  
Geochemical Characteristics ◽  
Coal Seams

scholarly journals Geochemical characteristics of elements in coal seams 41 and 42 of Heshan Coalfield, South China

2019 ◽  
Vol 38 (1) ◽  
pp. 137-157 ◽  
Author(s):  
Qiaojing Zhao ◽  
Yongjie Niu ◽  
Zhizhong Xie ◽  
Kuangming Zhang ◽  
Jinming Zhou ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Geochemical Characteristics ◽  
X Ray Diffraction ◽  
Coal Seams ◽  
X Ray ◽  
Inductively Coupled ◽  
Reducing Environment ◽  
Conventional Microscopy ◽  
Hydrothermal Activities ◽  
Scanning Electron

Coal seams 41 and 42 of the Heshan Coalfield belong to superhigh-organic-sulfur coals. In order to study the geochemical characteristics of the coals, 15 coal samples and 6 rock samples were collected from both coal seams and the roof/floor rocks. The samples were investigated by using conventional microscopy, inductively coupled plasma mass spectroscopy, X-ray diffraction, X-ray fluorescence, and scanning electron microscopy with an energy-dispersive X-ray spectroscopy. The results show that minerals in the coals are dominated by kaolinite and a mixed layer illite/smectite and illite; small ratios of pyrite, quartz, chlorite, smectite, calcite, and dolomite are also present. Under the microscope, these pyrites occur as framboidal, euhedral, homogeneous, anhedral, nodular, and fine dissemination shapes. In Shicun Mine, the trace elements Li, Y, Zr, Sn, Sm, and Tb are enriched; Zn and Ba are depleted. However, in the Heliluoshan Mine, Mo is significantly enriched; Li, Zr, Cs, and U are enriched; and Co and Ba are depleted. The occurrence of Li and Ga is associated mainly with organic matter and sulfate minerals. U and Mo occur in silicate minerals, carbonate minerals, illite, I/S, and pyrite. A reducing environment is beneficial for the enrichment of V, Cr, Mn, Ni, Mo, Cd, and U. The abundances of sulfur in Heshan were controlled mainly by the degree of seawater influence and hydrothermal activities.

Studies to the Coal Gas Draining Feasibility and Potential Evaluation

2011 ◽  
Vol 63-64 ◽  
pp. 728-731
Author(s):  
Chun Wei Hui
Keyword(s):  
Coal Mine ◽  
General Analysis ◽  
Gas Explosion ◽  
Gas Drainage ◽  
Mine Area ◽  
Coal Gas ◽  
Gas Outburst ◽  
Coal Mine Gas ◽  
Mine Production ◽  
Potential Evaluation

The coal mine gas can cause gas explosion and gas outburst, which is a direct threat to the safety of coal mine production. The gas drainage technology is the highlights in the research of highly gassy mine and coal and gas outburst. Coal gas drainage in the coal mine area includes ground gas development and underground gas drainage. Therefore, the evaluation to the draining feasibility of the coal gas should also be divided into ground coal gas development and underground gas drainage. Draining feasibility of the gas refers to the draining extent in a certain area and the possibility of the development under existing economical situations. By general analysis to the geological parameter that influences the draining feasibility, the drainage area will be optimized in this paper. With the reservoir bed data analog technology, the draining feasibility of the coal gas in the DaFosi field and its draining protential will the evaluated in this paper.

scholarly journals Numerical Investigation of Complex Thermal Coal-Gas Interactions in Coal-Gas Migration

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Xiaoyan Ni ◽  
Peng Gong ◽  
Yi Xue
Keyword(s):  
Coal Seam ◽  
Variable Temperature ◽  
Gas Pressure ◽  
Gas Migration ◽  
Coal Seams ◽  
Coal Seam Gas ◽  
Coal Gas ◽  
Thermal Coal ◽  
Gas Seepage ◽  
Gas Interactions

Understanding the influence of temperature on the gas seepage of coal seams is helpful to achieve the efficient extraction of underground coal seam gas. Thermal coal-gas interactions involve a series of complex interactions between gas and solid coal. Although the interactions between coal and gas have been studied thoroughly, few studies have considered the temperature evolution characteristics of coal seam gas extraction under the condition of variable temperature because of the complexity of the temperature effect on gas drainage. In this study, the fully coupled transient model combines the relationship of gas flow, heat transfer, coal mass deformation, and gas migration under variable temperature conditions and represents an important nonlinear response to gas migration caused by the change of effective stress. Then, this complex model is implemented into a finite element (FE) model and solved through the numerical method. Its reliability was verified by comparing with historical data. Finally, the effect of temperature on coal permeability and gas pressure is studied. The results reveal that the gas pressure in coal fracture is generally higher than that in the matrix blocks. The higher temperature of the coal seam induces the faster increase of the gas pressure. Temperature has a great effect on the gas seepage behavior in the coal seams.

scholarly journals Conceptual tendencies to analyze coal-gas system state under the hydroimpulsive effect

2019 ◽  
Vol 123 ◽  
pp. 01026
Author(s):  
Kostiantyn Sofiiskyi ◽  
Vasyl Zberovskyi ◽  
Anatolii Yalanskyi ◽  
Oleksii Yalanskyi
Keyword(s):  
Rock Mass ◽  
Injection Pressure ◽  
Graphical Analysis ◽  
System State ◽  
Coal Seams ◽  
Globular Structure ◽  
Maximum Deformation ◽  
Coal Gas ◽  
Gas System ◽  
And Control

The paper considers conceptual tendencies concerning the analysis of coal-gas system state within rock mass in front of a mine working stope in the context of hydroimpulsive effect on an outburst-prone coal seam. It has been shown that mining intensification is impossible without the improved efficiency of means indented to avoid gasdynamic phenomena taking into consideration the effect of technogenic factors on operation schedules. It has been determined that since grades of outburst-prone coal are of globular structure, its breakage may involve changes in molecular weight of coal substance and generation of methane and water molecules. In the context of a shear model of undermined rock mass, method of graphical analysis has been applied to determine areas of changes in border angles of demonstration of the initial and maximum deformation under the effect of rock bearing pressure. The determined dependences are described rather reliably by means of similar logarithmic curves which characterizes identity of their nature. Changes in filtration coal characteristics in the context of shear deformations have been considered. It has been proved experimentally that if injection pressure varies, periodically discontinuous fluid flow has initial, stable, and decaying stages being implemented in the forms of cavitation phenomena and high-frequency hydroimpulsive vibration. Sequence of methods to study parameters of hydroimpulsive action, evaluation of its efficiency, and control over a change in coal-gas system state of outburst-prone coal seams have been considered.

scholarly journals Geochemical Characteristics and Productivity Response of Produced Water from Coalbed Methane Wells in the Yuwang Block, Eastern Yunnan, China

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Mingyang Du ◽  
Xiaojuan Yao ◽  
Shasha Zhang ◽  
He Zhou ◽  
Caifang Wu ◽  
...  
Keyword(s):  
Water Samples ◽  
Coalbed Methane ◽  
Produced Water ◽  
Dissolved Inorganic Carbon ◽  
Geochemical Characteristics ◽  
Water Type ◽  
Coal Seams ◽  
Rock Interaction ◽  
Cbm Production ◽  
Using Data

Coalbed methane (CBM) well-produced water contains abundant geochemical information that can guide productivity predictions of CBM wells. The geochemical characteristics and productivity responses of water produced from six CBM wells in the Yuwang block, eastern Yunnan, were analyzed using data of conventional ions, hydrogen and oxygen isotopes, and dissolved inorganic carbon (DIC). The results showed that the produced water type of well L-3 is mainly Na-HCO3, while those from the other five wells are Na-Cl-HCO3. The isotope characteristics of produced water are affected greatly by water-rock interaction. Combined with the enrichment mechanisms of isotopes D and 18O, we found that the water samples exhibit an obvious D drift trend relative to the local meteoric water line. The 13C enrichment of DIC in the water samples suggests that DIC is mainly produced by the dissolution of carbonate minerals in coal seams. The concentration of HCO3-, D drift trend, and enrichment of 13CDIC in produced water are positively correlated with CBM production, which can be verified by wells L-4 and L-6.

Sign in / Sign up

Export Citation Format

Share Document