西南石油大学学报(自然科学版)

Previous Articles     Next Articles

Accumulation Conditions for Tight Oil in Xiagou Formation,Lower#br# Cretaceous,Qingxi Oilfield

Sun Weifeng1,2,3*, Song Yan2,3,4, Gong Yanjie2,3, Gui Lili2,3   

  1. 1. School of Resources and Geosciences,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China
    2. Research Institute of Exploration & Development,CNPC,Haidian,Beijing 100083,China
    3. State Key Laboratory of Enhanced Oil Recovery,Haidian,Beijing 100083,China
    4. College of Unconventional Natural Gas,China University of Petroleum(Beijing),Changping,Beijing 102249,China
  • Online:2015-12-01 Published:2015-12-01

Abstract:

Tight oil is the most realistic and easiest unconventional resource in Qingxi Oilfield. This present study deeply
discusses the basic favorable accumulation conditions for the tight oil from source rocks,reservoirs,cap rocks and reservoircap
assemblages. The results show that the source rocks of Xiagou Formation and Chijinpu Formation have high hydrocarbon
potential,with large thickness,high content of organic matters and favorable kerogen type. The reservoir property is poor with
low porosity and low permeability. However,the intensive tectonic activities not only form favorable traps for the accumulation
of oil,but also improve the reservoir property. The tectonic fractures and corrosion fractures are the main accumulation spaces
for the tight oil in Lower Cretaceous Xiagou Formation. The Xiagou Formation and Zhonggou Formation mudstone,and the
Paleogene mudstone and gypsum-salt rock are the main cap rocks for the tight oil of Qingxi Oilfield. Besides,two types of
source-reservoir-cap assemblage are found and there are self product-self reservoir and lower product-upside reservoir.

Key words: tight oil, accumulation conditions, Lower Cretaceous Xiagou Formation, Qingxi Oilfield, fractures

CLC Number: