扬子地区中新生代盆地成盆深部过程及对古生代盆地叠加效果浅析

On the Deep Shaping Process of Mesozoic-Cenozoic Basins and Their Relative Superposition Effect to Palaeozoic Marine Basins in Yangzi Region

从地壳的深部地质作用,讨论了扬子地区主要中、新生代原型盆地生成与发展的深部过程。认为扬子地区中、新生代盆地对古生代盆地的叠加方式各有所不同,对盆地下伏古生界海相烃源岩所产生的叠加效果也因古生代盆地改造程度的不同而有所不同。现今四川、江汉、苏北三个中、新生代盆地在三种不同的深部地球动力学背景下的沉降机制,制约了对下伏古生代盆地的叠加,依此出现了有利于或不利于古生代海相油气生成聚集的各种条件。提出了开展扬子地区海相领域油气地质工作的关键,是要研究推覆构造,评价海相油气成藏条件,分析海相古生界的破坏程度与保存条件,寻找仍被保留下来的“残留盆地”。

It is considered that there are different patterns of Mesozoic and Cenozoic Basins superimposing on underlying Palaeozoic Basins in Yangzi Region and thus there are different superimposition effects to the underlying Palaeozoic marine source rocks due to different extent of reconstruction of Palaeozoic Basins. Nowaday＇s Mesozoic-Cenozoic Sichuan, Jianghan and Subei basins restrict the superimposition to underlying Palaeozoic Basins under different deep geodynamic backgrounds, which results to different geological conditions that are favorable or unfavorable to hydrocarbon accumulation in the Paleozoic marine strata. It is suggested how to carry out the oil and gas exploration research for the marine formations in Yangzi region.