Fine description of unconventional clastic oil reservoirs

The latest researches reveal that studies on unconventional clastic oil reservoirs in China generally lag far behind those in other countries in respect of content and methodology. This study presents the definition and classification of unconventional oil reservoirs and analyzes the problems in the fine description of unconventional oil reservoirs. The key content of the fine description of unconventional oil reservoirs is summarized from four aspects: fine fracture characterization based on fine structure interpretation, reservoir architecture characterization based on sedimentary facies, characteristics of nanoscale microscopic pore structure of reservoir, and evaluation of source rock and “sweet spot zone”. Finally, this study suggests that development of fine description of unconventional clastic oil reservoirs in the future should focus on rock brittleness analysis and fracture modeling, geophysical characterization of unconventional clastic oil reservoirs, fluid description of tight reservoirs, and physical/numerical simulation experiments of unconventional oil reservoirs.