Classification and evaluation criteria of shale oil and gas resources: Discussion and application

Abstract Research on the evaluation criteria of shale oil and gas is conducted to accurately assess the resource potential of shale oil and gas. Statistic analysis of the geochemical index of hydrocarbon source rocks in five areas such as Songliao, Hailaer, Jiyang, based on the characteristic of triple-division between the oil content and TOC of source rock, suggests that shale oil and gas can be categorized into three levels of resource enrichment: scattered (ineffective) resources, low efficient resources and enriched resources. The mature stage, at which organic matter generates oil and gas in large amounts, corresponds to the shale oil and gas enrichment window. Furthermore, recoverable index is defined and its computation formula is proposed to provide a quantitative index for recoverability evaluation, considering the brittle mineral content, thickness and depth of shale, etc. In practice, TOC variable values in well profile obtained by TOC -logging correspondence can be used to draw TOC isopach maps and calculate the amount of resources at different levels. Then combined with the evaluation criteria, TOC and R o isopach maps are superimposed to identify the favorable shale oil and gasareas.

[1]  D. Welte,et al.  Petroleum Formation and Occurrence , 1989 .

[2]  David F. Martineau.  History of the Newark East field and the Barnett Shale as a gas reservoir , 2007 .

[3]  Wang Lan-sheng.  A preliminary study on accumulation mechanism and enrichment pattern of shale gas , 2009 .

[4]  H. Rogner.  AN ASSESSMENT OF WORLD HYDROCARBON RESOURCES , 1997 .

[5]  Cheng Ke-ming,et al.  Prospects and strategic position of shale gas resources in China , 2009 .

[6]  Lin Tuo,et al.  EXPLORATION POTENTIAL OF SHALE GAS RESOURCES IN CHINA , 2008 .

[7]  J. Curtis.  Fractured shale-gas systems , 2002 .

[8]  Dong Dazhong,et al.  Geological features, major discoveries and unconventional petroleum geology in the global petroleum exploration , 2010 .

[9]  Wenzhi Zhao,et al.  Further discussion on the connotation and significance of the natural gas relaying generation model from organic matter , 2011 .

[10]  Bian Rui-kang.  Controlling factors for shale gas accumulation and prediction of potential development area in shale gas reservoir of South China , 2009 .

[11]  Li Xin-jing.  Analysis of controls on gas shale reservoirs , 2009 .

[12]  Lu Zong-gang.  An evaluation method of shale gas resource and its application in the Sichuan basin , 2009 .

[13]  T. Yen,et al.  Petroleum formation and occurrence — A new approach to oil and gas exploration: B.P. Tissot and D.H. Welte. Springer, Berlin, 1978, 538 pp., DM 79.00 or U.S. $ 39.50 , 1979 .

[14]  Dong Da-zhong,et al.  Geologic controls on accumulation of shale gas in North America , 2009 .

[15]  Denghua Li,et al.  Geological characteristics and resource potential of shale gas in China , 2010 .