琼东南盆地生物礁的识别和分布演化特征

Identification and Distribution Evolution Characteristics of Bioherm of South Basin of Qiongdongnan

通过建立琼东南盆地西南部地区新近系层序地层格架,重点分析层序SQ11～16地层格架内生物礁的识别、类型、形成时代、分布规律和生长期次,指出地震剖面上识别礁体的地球物理特征,分析生物礁和生物丘形成环境的水动力差别。在层序内共识别出堡礁、塔礁、补丁礁、环礁4种类型。中新世是该区主要成礁期,平面分布形态与古地貌和海平面的升降有关,主要沿北西向大断裂呈半环形分布。礁体生长期次主要受海平面变化影响,划分出高频生长单元,并总结出了该区的成礁模式。

The paper majorly analyzes the identification,types,formation era,distribution regularity and growing stages of organic reef of formation framework of sequence stratigraphy 11 to 16,points out geophysical features in seismic profile and analyzes the hydraulic pressure difference under which organic reef and bioherm formed.Four types of reefs,namely,barrier reef,tower reef,patch reef and atolls,are identified among sequence stratigraphy.Middle Miocene is the major period of reef formation,in which lateral distribution shape has something to do with ancient landform and up-and-down of sea level and the distribution appeared in annularity toward large faults along NW.Reef body was mainly influenced by the variation in sea level.The paper classifies high frequency growing unit and summarizes reef-forming mode in this area.