基于沧东凹陷地震剖面和新生代残留盆地结构的详细分析,利用平衡剖面技术,结合沉积体系演变特征,系统研究了沧东凹陷的原型盆地构造演化过程.结果表明沧东凹陷新生代经历了坳陷期(孔三段-孔一下亚段沉积期)、断陷期(孔一上亚段-东营组沉积期)和坳陷期(馆陶组-平原组沉积期)3 个演化阶段.在断陷期,盆地演化主要受沧东和徐西两条边界断层的控制,盆地伸展作用具有逐渐减弱的特点,并且边界断层伸展作用具有自北西向南东迁移的特点.沧东凹陷新生代的构造演化受控于岩石圈上部简单剪切伸展和岩石圈下部纯剪切伸展的共同作用.

陆相气候敏感沉积物蕴含着丰富的古气候信息,是开展深时古气候研究的重要依据.我国学者利用陆相气候敏感沉积物对深时古气候演变开展了大量的研究工作,取得了丰硕的成果.介绍了常被应用于深时古气候研究的陆相气候敏感沉积物类型,并重点介绍了我国中东部白垩纪陆相气候敏感沉积物的研究进展.通过对我国中东部白垩纪陆相敏感沉积物分布特征的分析发现:在空间上,早白垩世的古气候环境可划分为半干旱气候区、干旱气候区与湿润气候区;晚白垩世的古气候环境可划分为干旱气候区、半干旱气候区与半湿润气候区.在时间上,与早白垩世相比,晚白垩世的干旱气候区范围有明显的扩张趋势,湿润气候区的范围逐渐向东北方向缩小.可见,白垩纪我国中东部气候环境整体上具有干旱化逐渐增强的趋势.最后针对陆相气候敏感沉积物研究存在的问题进行分析,并对其未来发展趋势进行了展望,以期为今后陆相气候敏感沉积物研究及其在深时古气候演变研究中的应用提供参考.

There exist divergent views about the Indosinian tectonic nature of basin and the evolution of basin-range pattern in the southwest margin of the Yangtze block. Detrital zircon U-Pb dating and detrital provenance analysis of sandstone samples from the Upper Triassic-Lower Jurassic of Xiangyun Section in the western Chuxiong basin were carried out. The results show that the detrital sources of the Upper Triassic Yunnanyi Formation and Luojiadashan Formation are mainly from the Middle-Lower Triassic and Permian in the Upper Yangtze region. The detrital sources of the Upper Triassic Baitutian Formation and the Lower Jurassic Fengjiahe Formation are mainly from the Songpan-Ganzi terrane and Kangdian ancient land. Combined with the sedimentary environment evolution and regional geological setting, it is considered that the orogeny is relatively weak during the earlier Late Triassic, and Chuxiong basin is an underfilled basin, whose clastic source supply is insufficient. From the later Late Triassic to Early Jurassic, the tectonic evolution of Chuxiong basin was controlled by the thrust nappe of Ailaoshan orogenic belt,but the sedimentary filling process of Chuxiong basin was mainly controlled by the rapid rise of Songpan-Ganzi orogenic belt.