西南石油大学学报(自然科学版)

    Next Articles

Characteristics and Calculation Method for Gas Content of Upper#br# Paleozoic Shales in the Eastern Margin of Ordos Basin

GUO Shaobin1, ZHAO Keying2*   

  1. 1. School of Energy Resources,China University of Geosciences(Beijing),Haidian,Beijing 100083,China;
    2. Department of Basic Subjects,Shanxi College of Energy Resources,Jinzhong,Shanxi 030600,China
  • Online:2016-02-01 Published:2016-02-01

Abstract:

Shale sequences are well developed in the Carboniferous–Permian transition facies,Ordos Basin. Researchers have
done many studies on shales in upper Paleozoic of the Ordos Basin. With few drilling data,however,not enough researches
have been carried out on the eastern margin of the basin. In order to clarify the characteristic and gas bearing of shales in the
eastern margin of the basin,according to the characteristic of sedimentary,geochemistry,lithology,physical property and the
experiments of isothermal adsorption and nuclear magnetic resonance of samples from Taitou,the shales were analyzed. It
is found that Taiyuan formation has the best condition for shale gas formation which is 25 meters thick,abundant in organic
matter,and is in the stage of producing gaseous hydrocarbon,the shale is of high content of non swellable clay minerals and
equally distributed crack/micro fractures. We also offer the calculation formula of gas adsorption using parameters of depth
and content of organic carbon and improve the calculation accuracy of free volume through calculating effective porosity. It
has been verified that the calculation of air content conforms to the actual situation,and the method is simple and practical by
relevant data from Well Y88 in Ordos Basin.

Key words: shale, adsorpted gas content, free gas content, upper Paleozoic, east margin of Ordos Basin

CLC Number: