琼东南盆地构造演化与含煤沉积作用研究

Research Prospect on Tectonic Evolution and Coal-bearing Sedimentary Action in Qiongdongnan Basin

琼东南盆地位于海南岛东南部海域,为新生代形成的北东走向伸展盆地。采用盆地构造演化及地层对比等分析方法,对琼东南盆地构造演化过程以及盆地内沉积成煤作用进行综合分析,认为琼东南盆地的构造演化具有幕式裂陷特征,裂陷期最后一幕的沉积地层(崖城组和陵水组)中有成煤作用的发生。通过含煤地层的沉积环境分析,认为崖城组属海陆交互相充填阶段,陵水组为浅海环境充填阶段。但该区还存在地层格架不清、煤层空间展布以及盆地演化机制不明等问题,是今后深入研究琼东南盆地的重要方向。

Qiongdongnan basin is located in the sea area of southeastern Hainan Island,it was a NE-direction extensional basin formed in Cenozoic Era.In this paper,the evolution processes of Qiongdongnan basin structures and the sedimentary incoalation in the basin were synthetically analyzed by using basin tectonic evolution,stratigraphic correlation and other analysis methods.The comprehensive analysis showed that tectonic evolution in Qiongdongnan basin was of the features of episodic rifting,coal formation occurred in the last rifting sediment strata（Yacheng formation and Lingshui formation）.From analysis on the sedimentary environment,we concluded that Yacheng formation was marine-terrigenous facies filling stage and Lingshui formation was neritic environment filling stage.However,the analysis on the research results in the area found that there still were some problems,i.e.,the unclear stratigraphic distributions,unknown coal bed spatial distribution and the mechanism of basin evolution in various stages,etc.,and all of them become the main directions of in-depth study of Qiongdongnan basin.