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Relationship between Thermal Metamorphism of Coal and the periodic variation Law of Geochemical Behavior of Elements:A Study on the C2 Coal Seam in the Fengfeng Mining Area of the Handan Coalfield in Hebei,China

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1684-1694页

作者： YANG Jianye QIN Shenjun ZHANG Weiguo LIU Shande XU Fei College of Material Science and Engineering Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory for Resource Exploration Research of Hebei Province Hebei University of EngineeringHandanHebei 056038China College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Xi’an Research Institute Co. Ltd.China Coal Science and Industry GroupXi’an University of Science and TechnologyXi’an 710077China

This study highlights the response of the periodic variation of the geochemical behavior of elements to the thermal metamorphism of coal by considering the differentiation mode and differentiation degree of elements of the C2 coal seam in the Fengfeng mining area of the Handan Coalfield in Hebei,*** periodic variation of the geochemical behavior of elements was observed to change towards a certain direction as the degree of metamorphism of a geological body *** on the coincidence degree(or similarity degree)between the geochemical behavior of elements and periodic variation of elements,the 57 elements in this study were divided into two *** periodic variation of the geochemical behavior of first-level elements was largely synchronous with that of their first ionization energy,suggesting that only one differentiation mode exists and the elements are mainly inorganically *** differentiation mode of the second-level elements deviated to a certain extent from their first ionization energy;the larger the deviation,the more complicated and diverse was the differentiation *** the second-level elements,the grade of coal metamorphism has evident and intuitive effects on the proportion of elements with particular structural features,such as the 4q+3 type of elements and the odd-odd *** addition,the distribution of elements in organic and inorganic matter within coal are subject to the structural features of the *** differentiation mode and differentiation intensity of elements could be characterized by the hierarchical parameter and differentiation *** hierarchical parameter and differentiation intensity of certain elements showed a good positive or negative correlation with R_(max) in *** 57 elements in this study were quantitatively ordered according to the degree of magmatic hydrothermal fluid influence and thermal metamorphism of coal through graphs depicting the goodness of fit,correlation coeffic

关键词： elements in coal geochemical behavior periodic variation thermal metamorphism magmatic hydrothermal fluids

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Effect of periodic wide atmospheric pressure change on CO emission in closed goaf

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International Journal of Coal Science & Technology 2023年第4期10卷 139-150页

作者： Zhuangzhuang Shao Bo Tan Ruili Hu Xiaozhen Song Yan Guo Tianze Li Shuhui Fu Chaohuan Chen Haiyan Wang School of Emergency Management and Safety Engineering China University of Mining and Technology(Beijing)Beijing 100083China Security Department University of International Business and EconomicsBeijing 100029China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China

Atmospheric pressure fuctuation is one of the most important factors afecting the climate environment and gas emission in the fre *** obtain the infuence rule of the surface atmospheric pressure change on the gas sampling and abnormal emission in the mine closed goaf,the No.1 coal mine in Dananhu was taken as the research *** Fourier transform and Fisher harmonic analysis and other statistical methods,the infuence of the periodic variation of atmospheric pressure on the gas leakage and outfow in the closed goaf was *** results showed that there were three atmospheric pressure periods of 15.2 d,1 d and 182.2 d,and the probability was greater than 95%.The time period with the highest number of atmospheric pressure peaks was 7:00–8:00,which accounted for 20.2%of total occurrence number in a *** the time periods with the highest number of atmospheric pressure trough were 2:00,15:00 and 16:00,accounting for 27.4%.The peak-to-trough transition time was mainly concentrated around 6 h,and the diurnal variation curve of atmospheric pressure was mainly *** atmospheric pressure change rate was mostly concentrated in 10–50 Pa/*** was determined that the distance that the gas sampling pipe was pre-laid into the inner side of the closed wall should be greater than 44.4 m,and the CO concentration and atmospheric pressure in the closed goaf were both periodic and negative with atmospheric *** research results have important guiding signifcance for the monitoring,early warning and environmental protection of the goaf.

关键词： Atmospheric pressure periodic variation Closed goaf CO emission Coal mine

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GPS time-series and its response to M_S=8.1 Kunlunshan earthquake

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Acta Seismologica Sinica(English Edition) 2005年第4期18卷 419-426,499页

作者：敬少群吴云乔学军周硕愚施顺英 Institute of Seismology China Earthquake Administration

In this paper, observation data in 25 GPS reference stations of China have been analyzed by calculating GPS position coordinate time-series with GIPSY. Result shows there is an obvious trend variation in such time-series. The trend variations of time series along the longitude and latitude coordinate reflect the motion of each position in the global-plate, in which the trend variation in the vertical direction reveals some large-scale construction information or reflects the local movement around the positions. The analysis also shows that such time-series have a variation cycle of nearly 1.02 a, but the reason still remains to be further studied. At the end of this paper, response of the time-series to MS=8.1 Kunlunshan earthquake was analyzed, and the seismogenic process of MS=8.1 Kunlunshan earthquake, according to the time proceeding and the feature of anomaly, was divided into 3 phases-changes in blocks with forces, strain accumulation, quick accumulation and slow release of energy. At the initial stage of seismogenic process of MS=8.1 earthquake and at the imminent earthquake, coseismic process as well as during the post earthquake recovery, anomaly in vertical direction is always in a majority. The anomalous movement in vertical direction at the initial stage resulted in a blocking between faults, while at the middle stage of seismogenic process, the differential movement between blocks are in a majority, which is the major reason causing energy accumulating at the blocking stage of faults.

关键词： GPS time-series trend variation periodic variation seismogenic process blocking between faults energy accumulation

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Trends and abrupt changes in surface vapor content over Tarim Basin during the last 50 years

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Journal of Arid Land 2012年第3期4卷 260-270页

作者： HongJun LI WeiYi MAO Yong ZHAO MinZhong WANG Wen HUO Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Xinjiang Climate Center China Meteorological Administration Urumqi 830002 China

The surface vapor content has a close correlation with the generation of precipitation. Based on the atmospheric circulation data and surface vapor content data from 37 weather stations across the Tarim Basin dur- ing 1961-2010, the paper analyzed the vapor variation trend, period, abrupt changes and their causes. The results show that the increase trend of surface vapor content over the Tarim Basin mostly conforms with the average trend coefficient of 0.48. There were 3 centers displaying a trend of high vapor increase and 3 centers displaying a low vapor increase. These centers were distributed in strips and blocks across the basin from northeast to southwest. Notable inter-decadal variations in annual and seasonal vapor contents occurred in the Tarim Basin during the 50 years of the study period, with more vapor after the mid-1980s and less vapor in the 1960s and the 1970s. The significant increase in vapor content in the 50 year period occurred mostly in the 1980s and the 1990s. The in- creasing trend across the four seasons was strongest in summer, reaching 0.43, and weakest in spring. Great variations existed between the spring trend and the annual, summer, autumn and winter trends. During the 50-year study period, there are distinguishable periods of 4-6 years and 8-10 years in which the annual and seasonal vapor contents varied alternately between low and high concentrations. The annual vapor content and that of the four individual seasons all changed abruptly in about the mid-1980s （a〈0.05）. The west wind circulation, Tibetan Plateau circulation and the annual mean temperatures of the Tarim Basin are the main factors that influenced the surface vapor content over the study area, of which the Tibetan Plateau circulation may be the most important one.

关键词： surface vapor content climate factors periodic variation abrupt change Tarim Basin

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Possible effect of ENSO on annual sediment discharge of debris flows in the Jiangjia Ravine based on Morlet wavelet transforms

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International Journal of Sediment Research 2008年第3期23卷 267-274页

作者： J. H. ZHANG1, F. Q. WEI2, S. Z. LIU3, C. GAO41 Dr., Research Scientist, Hainan Meteorological Science Institute, South-Sea Meteorology & Disaster Mitigation Research Key Laboratory, Haikou, China, No. 60 Haifu Road, Haikou, China, 2 Dr., Research Scientist, 3 Research Scientist,4 Dr.,Institute of Mountain Hazards and Environment, CAS, No. 9, Sec. 4, South Renmin Road, Chengdu, China Dr. Research Scientist Hainan Meteorological Science Institute South-Sea Meteorology & Disaster Mitigation Research Key Laboratory Haikou China No. 60 Haifu Road Haikou China Dr. Research Scientist Research Scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China Dr. Research Scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China

The multi-time-scale structures of an annual sediment discharge series of debris flow in the Jiangjia Ravine and the Southern Oscillation index are analysed using the method of Morlet wavelet transformations. The possible effects of El Nio episodes on the annual sediment discharge are discussed by comparing the period variations of ENSO and the discharge. The results show that the annual sediment discharge series of debris flow is related to El Nio episodes. Generally, the annual sediment discharge of debris flow is less than usual during an El Nino episode and debris flow is less active. On the contrary, the annual sediment discharge of debris flows is greater than usual during a La Nia episode and debris flows are more frequent. There is a relationship between the annual sediment discharges of debris flow in the Jiangjia Ravine and the summer Southern Oscillation index, with both having quasi-periodic variations of 2 and 5–6 years.

关键词： Debris flow ENSO Wavelet transform periodic variation

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朝阳地区百年降水变化特征及趋势(英文)

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Meteorological and Environmental Research 2010年第1期1卷 26-29页

作者：周国华谭明军穆春华常忠波辽宁省凌源市气象局辽宁凌源122500 辽宁省朝阳市气象局辽宁朝阳122500

According to the precipitation sequence of Beijing City from 1900 to 1958,the precipitation sequence of Chengde City were revised and *** the precipitation sequence of Chaoyang City were revised and extended with the precipitation sequence of Chengde City to form 100-years precipitation sequence of *** results showed that the 100-years precipitation sequence of Chaoyang indicated a decreasing trend and obvious periodic variation with the change of *** is,a 10-year rainy period (approximately 525.0 mm) appeared every 30 a,while the 30-year drought period was approximately 460.0 mm,65.0 mm lower than the ***,an obviously heavy drought lasting for 2-4 a appeared every 20 a.

关键词： 100-years precipitation Sequence revision periodic variation Characteristics Tendency China

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锦州地区大风气候特征及环流形势分析(英文)

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Meteorological and Environmental Research 2010年第6期1卷 23-26页

作者：杨桂娟鄢志宇辽宁省锦州市气象局辽宁锦州121001

Based on the gale observation data in 5 observation stations in Jinzhou area from 1973 to 2007,the gale trend and the periodic change in Jinzhou area were analyzed by using the linear trend estimation method and the spectral analysis method. Meanwhile,the circulation situation characteristics and the spatial-temporal distribution characteristics of gale in four seasons were discussed by surveying generally the weather charts. The results showed that the gale in Jinzhou area presented the fluctuation decline trend and had 3.5,7.0 years periodic changes. The gale in spring is the most and in summer was the least. It was less in winter and autumn. Seen from the analysis on the circulation situation,the gale circulation situation in Jinzhou area was similar to in Liaoning. The circulation situation in spring was basically consistent with in autumn,winter. The main situations had 3 kinds:north high south low(west high east low) ,two high clipping low,south high north low(east high west low) . In summer,the regional gale weather was mainly caused by the meso-micro scale system.

关键词： Gale periodic variation Spatial and temporal distribution Circulation characteristics China

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