层序充填动力学——层序地层研究的新方向

层序地层学经过近半个世纪的发展 ,研究领域由当初的被动大陆边缘盆地扩展到了活动大陆边缘盆地、前陆盆地和陆相盆地 ;从研究全盆地的层序地层到研究盆地中某一具体相带的层序地层 ,研究时代也从起初的中新生代拓宽到了古生代。定年技术的发展和同位素等手段的使用 ,使得对层序级别的划分越来越细 ,对层序发育控制因素的研究更加具体 ,冰川、气候、沉积物供应速率等因素对高级别 (三级或三级以上 )层序发育的控制较为明显 ,但对影响层序发育四大因素 (全球海平面变化、构造、气候、沉积物供应 )的动力机制一直未作根本性的探讨 ;大陆地质是地球动力学的信息库 ,沉积盆地是大陆地质过程的信息反馈和载体 ,是壳、幔动力活动的记录和见证 ,层序作为盆地演化的充填块体 ,记载着盆地的成生、发展、演化的信息 ,层序的旋回性是地球运动节律的直接反映。因此 ,以此为研究对象的层序充填动力学是沉积盆地动力学乃至地球动力学研究的基础 ,是层序地层研究的新方向。

SEQUENCE-FILLING DYNAMICS--A NEW STUDY DIRECTION ON SEQUENCE STRATIGRAPHY

After the development of about fifty years, the study field of sequence stratigraphy has been expanded from passive continental marginal basin to active continental marginal basin, forland basin and terrestrial basin. Formerly we studied only the sequence strata of the whole basin and now we have studied the sequence strata of specific facies of basin and the sequence stratigraphy which originated from the passive continental marginal basin of Mesozoic and Cenozoic ages, now research all kinds of basins of Paleozoic age. Dating technological development and usage of isotope makes the division of sequence increasingly exquistite, and the study of controlling factors more and more detailed. Glacier, climate and supply ration of sediments control obviously the third-grade sequence or higher classic sequence, but the study on dynamics of four factors (such as global sea level change, tectonics, climate and supply of sediments), which have an impact on the sequence formation, have not been intensively studied. However the continental geology is the data bank of the geological dynamics, and the depositional basin is the supporter and information feedback of the continental geology process, recording and proving the crust-mantle action. Sequence, which is regarded as the basic unit of filling basin, recorded the information about basin formation, deve- lopment and evolution. The cycles of the sequence reflect directly globe motion rhythm. Hence sequence-filling dynamics is the bases of basin dynamic and global dynamics and it represents a new direction of the sequence stratigraphic study.