Multiple-stacked Hybrid Plays of lacustrine source rock intervals: Case studies from lacustrine basins in China

Abstract

Abstract Hydrocarbon-producing lacustrine basins are widely developed in the world, and China has a large number of lacustrine basins that have developed since the early Permian. The organic-rich shale-dominated heterogeneous source rock intervals in Chinese lacustrine basins generally contain frequent thin interbeds of stratigraphically associated sandstone, siltstone, marl, dolomite, and limestone. The concept of “Hybrid Plays” as put forth in this article recognizes this pattern of alternating organic-rich shale and organic-lean interbeds and existence of mixed unconventional and conventional plays. Hybrid Plays in lacustrine source rock intervals present a unique closed petroleum system hosting continuous hydrocarbons. The interbedded organic-lean siliciclastic and/or carbonate plays are efficiently charged with hydrocarbons via short migration pathways from the adjacent organic-rich shale that is often also a self-sourced play. We assert “Hybrid Plays” provide the most realistic exploration model for targeting multiple-stacked and genetically related very tight shale, tight and conventional plays together in the entire source rock interval rather than individual plays only. The Hybrid Play model has been proven and works for a wide variety of lacustrine rift, sag and foreland basins in China.

Keywords

• Lacustrine basin
• Hybrid Plays
• Shale
• Interbed
• Source rock
• Petroleum system