珠江口盆地白云凹陷东沙25凸起构造演化  

Tectonic Evolution of Dongsha 25 Uplift in the Baiyun Sag, Pearl River Mouth Basin

作　　者：张翠梅[1] 赵中贤[1] 孙珍[1] 庞雄[2] 柳保军[2] 李鹏春[1] 

机构地区：[1]中国科学院南海海洋研究所边缘海地质重点实验室,广州510301 [2]中国海洋石油有限公司深圳分公司研究院,广州510240

出　　处：《吉林大学学报（地球科学版）》2013年第1期57-66,共10页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金青年基金项目(41106055);中国科学院南海海洋研究所青年人才领域前沿项目(SQ201010);国家科技重大专项(2008ZX05025-006-001);海底科学重点实验室开放基金项目(KLSG1101)

摘　　要：隆起带的形成和演化分析对于油气勘探具有重要的指导意义。通过对比生长地层法、沉降史回剥技术和剩余构造沉降3种构造演化的手段,旨在全面揭示东沙(DS)25凸起的演化历史。依据生长地层的厚度、地层反射终端等特征划分出白云凹陷DS25凸起演化的主要阶段;运用回剥法恢复DS25凸起的沉降历史和与周缘地区的沉降差异;结合剩余构造沉降分析,定量判断隆起的抬升、沉降和差异沉降作用及发育时期。在对以上3种方法对比综合的基础上,综合生长地层指示的重要构造变革界面、沉降史恢复和剩余构造沉降精细划分的沉降阶段和构造运动形式,重建DS25凸起演化过程,并提出以下5个演化阶段:65～30Ma,凸起顶部遭受强烈剥蚀;30Ma左右,凸起发生大规模抬升;30～23.8Ma,发生微弱沉降;23.8～10.5Ma,发生差异沉降,并出现三幕强烈沉降;10.5Ma至今,凸起经历持续抬升。Abstract： Research on the uplifts tectonic history is significant for hydrocarbon exploration. This study aims to investigate the evolution of Dongsha （DS） 25 upli{t in Baiyun sag, Pearl River Mouth basin, by integrating and comparing with growth strata, back-stripping technique and remnant tectonic subsidence approach associated with tectonic evolution. The growth strata in terms of the strata thickness variation, seismic reflections terminal geometry indicate that the development of the DS25 uplift could be divided into several main stages. Besides, resorting to back-stripping technique, we interpreted subsidence history of the DS25 uplift. Furthermore, by combining with estimation of remnant tectonic subsidence, the movement and development period of the uplift are accessed. By comparison with the above three methods, we integrated the major tectonic events interfaces deduced from growth strata, rapid or weak subsidence stages, the uplift ascending or subsiding movement etc. , and presented that the DS25 uplift experienced following five stages. From 65 Ma to 30 Ma, the uplift suffered strong erosion. Before 30 Ma, the DS25 uplift underwent strongly uplift. From 30 Ma to 23.8 Ma, it experienced weak subsidence. From 23. 8 Ma to 10. 5 Ma, it subsided rapidly, which can be subdivided into three episodes according to different subsidence rates. From 10.4 Ma to present, the uplift was affected by the Dongsha movement and kept continuously ascending.

关 键 词：白云凹陷 东沙25凸起 生长地层 沉降史 珠江口盆地 油气 

分 类 号：P542[天文地球—构造地质学]