沉积盆地“源-汇”系统研究进展

Progress in “Source-to-Sink” system research

"源-汇"系统指盆地中自剥蚀地貌中形成的剥蚀产物,搬运到沉积区或汇水盆地中最终沉积下来的过程。在当前沉积学领域中"源-汇"系统占有重要一席。通过系统梳理国内外文献,评述"源-汇"系统各要素及其耦合作用研究进展,认为源区是控制系统动态过程根本要素,搬运-沉积过程是物源供给不同级次的响应。源区古地理演化下物理和化学风化作用控制物源供给,物源供给时空属性则决定搬运方式和通道类型。之后搬运中地质作用重塑沉积物组分和结构,而源区扰动和搬运响应两者时间尺度关系决定改造效果。最终源区演化形成的沉积地貌变化造成盆内可容纳空间分异,促使沉积物选择性沉积,塑造了盆内千姿百态沉积面貌。"源-汇"系统先进于其正演化、定量化和动态化研究思路,但研究方法仍处于探索阶段,而要完善研究体系则需着眼于物源体系研究,多时间尺度地质定量化表征方法,多学科交叉动态化研究方法。

The ＂Source-to-Sink＂system concerns with various components of sedimentary systems,from source areas,through dispersal systems,thence to deposition in a number of potential sedimentary sinks.It plays an important role in recent sedimentology research.This paper overviewed literatures at home and abroad,and discussed the research advance made on the important elements in the＂Source-to-Sink＂system and the coupling effect of the elements.Numerous studies indicated that the first-order control on the system is the source area,while the transport and sedimentary processes are response,at different process level,to sediment supply.The effect of physical and chemical weathering,resulted from paleogeographic evolution of the source area,controls sediment supply;and the temporal and spatial attributes of sediment supply determine the transport mode and channel type.Subsequently,the geologic processes reshape sediment component and structure;and the modification effects rely on the ratio between the timescales of a perturbation in the source area and the transport response.Ultimately,sediment selectively deposits in the basin＇s spatially differentiated accommodation space-generated by the sedimentary geomorphology evolution in response to source evolution,and molds the various sedimentary features.Distinguished from other studies,the ＂Source-to-Sink＂system focuses on forward-evolutionary,quantitative and dynamic research.Nevertheless,the research technique of＂Source-to-Sink＂is still exploratory.This paper suggests that future developments should include provenance system research, multi-timescale quantitative geological characterization,and dynamic analysis with multidisciplinary approach.