致密气(英语:tight gas)是指在渗透率非常低的储层岩石中的天然气,它的生产需要大规模水力压裂才能达到符合经济效益的产量。这种天然气一般不含凝析油。故被称为干气(英语:dry gas)。这些产生干气的不渗透储层也被称为“致密砂岩”(英语:tight sand[1]。 一般致密气藏通常定义为基质渗透率低于 0.1 毫达西 (mD) 和基质孔隙度低于 10%[2][3]。 致密气最常在砂岩,但有时在石灰岩。致密气被认为是一种非常规天然气资源。致密砂岩多属古生代地层。因受长期地质作用,降低了岩石的渗透性,天然气被困在这些岩层中。水平钻井和水力压裂 一般被常用于致密砂岩的气田开发。水平钻井可增加生产管在岩层中长度,水力压裂可增加岩层的破裂带能加速气体流动。故两者实施可增加气田产能[4]

参考文献

  1. ^ "Tight Gas – an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2021-04-25
  2. ^ Ben E. Law and Charles W. Spencer, 1993, "Gas in tight reservoirs-an emerging major source of energy," in David G. Howell (ed.), The Future of Energy Gasses, US Geological Survey, Professional Paper 1570, pp. 233–252
  3. ^ Ali Sharif, Tight gas resources in Western Australia, Western Australia Department of Mines and Petroleum, Sept. 2007
  4. ^ McCoy, Mark; W. Neal Sams (2007). "Tight Gas Reservoir Simulation: Modeling Discrete Irregular Strata-Bound Fracture Networks and Network Flow, Including Dynamic Recharge from the Matrix" (PDF). National Energy Technology Laboratory. Retrieved 27 October 2011