Wang M.,China University of Mining and Technology |
Wang M.,Key Laboratory of CBM Resource and Reservoir generating Process |
Zhu Y.-M.,China University of Mining and Technology |
Zhu Y.-M.,Key Laboratory of CBM Resource and Reservoir generating Process |
And 2 more authors.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2012
In this paper, based on the research on gas geological characteristics of 10 pairs of outburst mines, we analyzed the gas content, pressure and measured data of emission quantity, summarized the rules of gas geology in Kailuan Mining Area, and put forward the gas occurrence under stepwise tectoniccontrol mode. The results show that the axial part of syncline structure is beneficial to the gas occurrence, and the gas unusual district distribution is controlled by the distributions of reverse fault, groundwater runoff and magmatic rock. Meanwhile, the tectonic setting of gas occurrence is established by the regional structure, while the gas occurrence in Kailuan Mining Area is controlled by the strurctures in the mining area level. Moreover, the gas distribution is different in each syncline structure, and the gas occurrence in one mine is controlled by the structures in the mine area. Source
Zou M.,China University of Geosciences |
Zou M.,Key Laboratory of CBM Resource and Reservoir generating Process |
Wei C.,China University of Geosciences |
Wei C.,Key Laboratory of CBM Resource and Reservoir generating Process |
And 3 more authors.
Mining Science and Technology | Year: 2010
Based on regional CBM geological characteristics and drainage data of three typical Coalbed Methane (CBM) wells in the southern Qinshui Basin, history matching, productivity prediction and factor analysis of gas production control are conducted by using COMET3 reservoir modeling software. The results show that in the next 20 years, the cumulative and average daily gas production of the QN01 well are expected to be 800×104 m3 and 1141.1 m3/d, for the QN02 well 87×104 m3 and 1202.7 m3/d and 97.5×104 m3 and 133.55 m3/d for the QN03 well. Gas content and reservoir pressure are the key factors controlling gas production in the area; coal thickness, permeability and porosity are less important; the Langmuir volume, Langmuir pressure and adsorption time have relatively small effect. In the process of CBM recovery, the material source and driving force are the key features affecting gas productivity, while the permeation process is relatively important and the desorption process has some impact on gas recovery. © 2010 China University of Mining and Technology. Source
Shen Y.-L.,China University of Mining and Technology |
Shen Y.-L.,Key Laboratory of CBM Resource and Reservoir generating Process |
Guo Y.-H.,China University of Mining and Technology |
Guo Y.-H.,Key Laboratory of CBM Resource and Reservoir generating Process |
And 3 more authors.
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2012
Based on the observation and description of outcrop and drill cores, correlation of well logging, granularity analysis, identification of rock thin section, the delta formed from Carboniferous to Permian were divided into four types. Variety factors, which control the deposition mechanism of delta, are considered in this classification scheme. These types and features of delta were controlled by many factors, for instance, paleotopography, river type, density difference between river water and water basin, hydrodynamic condition of water basin, etc. The results are as follows. In the Taiyuan stage of the early Permian, shallow water meandering river delta develops with epicontinental sea background, and has the characteristics of plane jet, weak underflow and low extension of sand body. It develops shallow water meandering river delta in the residual epicontinental sea-coastal lakes background in the Shanxi stage of the early Permian, with the features of axial jet, significant river-controlling effect and lobate plane. Shallow water braided river delta formed in coastal inland lakes grows in Shihezi stage of middle Permian. The sand body extends relatively far due to plane jet; and mult-stage erosion and overlay are obvious. There is the inland lake delta developed in the Shiqianfeng stage of late Permian. Source
Shao Y.,China University of Mining and Technology |
Shao Y.,Key Laboratory of CBM Resource and Reservoir generating Process |
Guo Y.,China University of Mining and Technology |
Guo Y.,Key Laboratory of CBM Resource and Reservoir generating Process |
And 5 more authors.
Mining Science and Technology | Year: 2011
In order to discuss the geochemical characteristic of REEs (rare earth elements) and their geological application, we measured the contents of rare earth elements, trace elements and minerals of 29 Lopingian (Late Permian) mudstone samples in Panxian county, carrying out ICP-MS and XRD analysis. The results show that the amount of REEs (185.56-729.46 × 10-6) is high. The ratios of w(LREE)/w(HREE) (6.84-13.86) and w(La)N/w(Yb) N (1.01-3.02) show clear differentiation of LREEs and HREEs. ΣREE has a significantly or critically positive correlation with lithophile elements Th, Nb, Ta, Ti, Ga, Sc, Cs, Zr, Hf, Sr, Be and chalcophile element Zn, a critically negative correlation with siderophile element Fe and a slightly positive correlation with illite, illite smectite mixed layers and siderite. REEs originate mainly from terrigenous minerals, in an inorganic phase. Source rocks of our samples consist of Emeishan basalt and a small part of sedimentary rocks, as suggested by the distribution patterns of REEs and w(∑REE)-w(La)/w(Yb) diagram. Moreover, abnormal surfaces near the sequence boundaries (SB2, SB3, SB4) are related with the boundaries, identified by geochemical characteristics of the REEs, such as ∑REE, w(LREE)/w(HREE), Eu/Eu and Ceanom. © 2011 Elsevier B.V. All rights reserved. Source
Wei C.,China University of Mining and Technology |
Wei C.,Key Laboratory of CBM Resource and Reservoir generating Process |
Qin Y.,China University of Mining and Technology |
Qin Y.,Key Laboratory of CBM Resource and Reservoir generating Process |
And 4 more authors.
International Journal of Coal Geology | Year: 2010
This paper presents a numerical study on the formation history of coalbed methane (CBM) reservoir in the southeast edge of Ordos Basin, China. The coal seams studied belong to the Late Palaeozoic coal-bearing series. These coal seams have a burial history and experienced the process of subsidence, rapid subsidence alternated with uplift and then uplift, sequentially, and underwent the geothermal actions at normal, extremely high, and then normal temperatures, respectively. Coal organic matter of the coal seams matured in the Triassic Period and in the Late Jurassic to Early Cretaceous Period. The results from numerical simulation reveal that CBM reservoir evolution history can be classified into five stages, namely primary, initial, stagnant, active and dissipative stages. In the first (primary) stage, coal rank was very low and there was little methane generated and stored in the coal seams. In the second (initial) stage, the coal was converted to middle-high volatile bituminous coal. As a result, a certain amount of methane was generated and began to accumulate in coal seams except part of it escaped from coal seams by diffusion and cap outburst. In the third (stagnant) stage, generation of methane was almost stagnant due to the temperature of the coal seam that dropped slightly and the maturation of coal organic matter stopped. Meanwhile CBM would keep dissipating through diffusion. In the fourth (active) stage, coal rank varied from high volatile bituminous coal A to semianthracite which accelerated pyrolysis gas formation and resulted in a large amount of methane generated at a high speed. During this period, CBM was increasingly accumulated in coal seams although there would be considerable amounts of gas dissipated from the coal seams. In the last (dissipative) stage, due to coal seams uplifted at various rates and no more methane generated, CBM was continuously dissipated by diffusion throughout the whole coal seams and by permeation at some local areas. The simulation provides insights for further interpretation of how many factors that control or affect the CBM reservoir formation history and CBM accumulation. These factors include features of coal-bearing series, characteristics of coal seams, physical properties of coal reservoir, tectonic evolution history, burial history and geothermal conditions, etc. In particular, tectonic evolution history and gas generation are critical. Under given conditions, CBM reservoirs in the study area were developed in different ways and the CBM was accumulated in the reservoirs at different levels. For example, the west part of study area is favourable for CBM accumulation. As a result, the gas content of the main coal seams in this region has a maximum of about 28 m3/t at depths of 900-1100 m, and generally increases with the increasing of burial depth from the east to the west. The coal reservoir is under-saturated in the east part where the burial depth is shallower than about 500 m while the west part is saturated. There is a close correlation of the lateral distribution of both gas content and saturation to the gas generation in the geological history. © 2009 Elsevier B.V. Source