The Jurassic Yanan Formation is one of the most important coal-producing formations and hydrocarbon source rocks in the Ordos Basin, North China. To evaluate the shale gas potential of the Yanan shale, a total of 48 s...The Jurassic Yanan Formation is one of the most important coal-producing formations and hydrocarbon source rocks in the Ordos Basin, North China. To evaluate the shale gas potential of the Yanan shale, a total of 48 samples from north Ordos Basin were sampled, and their geochemical, petrological, mineralogical and pore characteristics were investigated. It was found that the shale samples are a suite of early mature source rock. The total organic carbon(TOC) content ranges from 0.33% to 24.12% and the hydrogen index(HI) ranges from 43.31 mg/g to 330.58 mg/g. The relationship between Tmax and HI indicates the organic matter is type Ⅱ-Ⅲ. This conclusion is also supported by the organic petrological examination results, which shows that the kerogen is mainly liptinite and vitrinite. Minerals in the samples are composed mainly of quartz, clay and feldspar, and the clay minerals are composed of prevailing kaolinite, illite/smectite, chlorite and a small amount of illite. Under scanning electron microscope, OM pores in the Yanan shale are scarce except pores come from the kerogen intrinsic texture or clay aggregates within the organic particles. As the weak compaction caused by shallow burial depth, interparticle pores and intraparticle pores are common, the hydrocarbon storage capacity of the Yanan shale was improved. According to evaluation, the Yanan shale is considered as a good shale gas reservoir, but its hydrocarbon potential is more dependent on biogenic and coal-derived gas as the thermogenic gas is limited by the lower thermal maturity.展开更多
The objective of this paper is to explore the reliability of Online Automatic Scoring(OAS)through the comparison of OAS and Teacher Scoring(TS),and further demonstrate the feasibility of the integration of the two sco...The objective of this paper is to explore the reliability of Online Automatic Scoring(OAS)through the comparison of OAS and Teacher Scoring(TS),and further demonstrate the feasibility of the integration of the two scoring methods.The Pearson correlation statistics of the two scoring results of 115 compositions are processed with SPSS analysis software,indicating that the correlation between the two reaches 0.83,which means that OAS is relatively reliable in dealing with students’compositions.After the second stage of the TS experiment,the questionnaire results show that students generally recognize the OAS and have a clear understanding of the advantages and disadvantages of the two scoring methods.Combined with the students’interview,the conclusion is that the OAS is reliable and the integration of the two scoring methods will have a better effect.展开更多
基金supported by the Ordos administrative district, Ordos Basin shale gas resource potential investigation and evaluation program (grant No. 2013CGKY0893)funded by the Ordos city energy investment and development Co., LTDthe National Natural Science Foundation of China (grant No. 41872124)
文摘The Jurassic Yanan Formation is one of the most important coal-producing formations and hydrocarbon source rocks in the Ordos Basin, North China. To evaluate the shale gas potential of the Yanan shale, a total of 48 samples from north Ordos Basin were sampled, and their geochemical, petrological, mineralogical and pore characteristics were investigated. It was found that the shale samples are a suite of early mature source rock. The total organic carbon(TOC) content ranges from 0.33% to 24.12% and the hydrogen index(HI) ranges from 43.31 mg/g to 330.58 mg/g. The relationship between Tmax and HI indicates the organic matter is type Ⅱ-Ⅲ. This conclusion is also supported by the organic petrological examination results, which shows that the kerogen is mainly liptinite and vitrinite. Minerals in the samples are composed mainly of quartz, clay and feldspar, and the clay minerals are composed of prevailing kaolinite, illite/smectite, chlorite and a small amount of illite. Under scanning electron microscope, OM pores in the Yanan shale are scarce except pores come from the kerogen intrinsic texture or clay aggregates within the organic particles. As the weak compaction caused by shallow burial depth, interparticle pores and intraparticle pores are common, the hydrocarbon storage capacity of the Yanan shale was improved. According to evaluation, the Yanan shale is considered as a good shale gas reservoir, but its hydrocarbon potential is more dependent on biogenic and coal-derived gas as the thermogenic gas is limited by the lower thermal maturity.
基金Funded by Shandong Social Science Planning Program(山东省社科规划项目).
文摘The objective of this paper is to explore the reliability of Online Automatic Scoring(OAS)through the comparison of OAS and Teacher Scoring(TS),and further demonstrate the feasibility of the integration of the two scoring methods.The Pearson correlation statistics of the two scoring results of 115 compositions are processed with SPSS analysis software,indicating that the correlation between the two reaches 0.83,which means that OAS is relatively reliable in dealing with students’compositions.After the second stage of the TS experiment,the questionnaire results show that students generally recognize the OAS and have a clear understanding of the advantages and disadvantages of the two scoring methods.Combined with the students’interview,the conclusion is that the OAS is reliable and the integration of the two scoring methods will have a better effect.
