盆地形成与演化的动力学类型及其地球动力学机制

借鉴国内外已有的盆地研究成果,在盆地分析的基础上,从岩石圈板块作用、岩石圈深部作用和岩石圈表生作用3个方面,兼顾系统性、科学性和应用性,确立了盆地新的分类原则,由此深入研究了盆地形成与演化的动力学类型,并进一步阐述了盆地形成与演化的地球动力学机制。研究结果表明:在盆地分类中,首先主要根据盆地形成的地球动力学环境如岩石圈板块作用环境、深部作用环境以及表生作用环境来划分大类;再根据盆地形成与演化的各种地质作用及其动力学过程如构造作用(伸展、挤压或剪切过程)、热力作用及重力作用进行主要类型划分;再根据盆地的基底性质和地壳类型(如陆壳、洋壳或过渡壳)以及盆地的沉积充填史和构造古地理等(如海相盆地、陆相盆地或过渡相盆地)细分亚类。盆地形成与演化的动力学类型主要包括:单一构造或热体制下盆地演化时的原型盆地类型、单一重力体制下盆地演化的原型盆地类型、多种构造-热体制下盆地演化的叠合盆地类型以及多种构造-热体制下盆地演化的残留盆地类型。在单一构造或热体制下,从板块作用或壳幔作用角度原型盆地动力学类型主要划分为:伸展盆地(陆内伸展盆地、陆间伸展盆地、大洋伸展盆地和弧后伸展盆地),挠曲盆地(弧后挠曲盆地、周缘挠曲盆地、陆内挠曲盆地),走滑盆地(走滑伸展盆地、走滑挠曲盆地)以及克拉通盆地(克拉通退缩盆地、克拉通扩展盆地和克拉通迁移盆地);单一重力体制下原型盆地动力学类型有负载盆地和撞击盆地;多种构造-热体制下的叠合盆地动力学类型有叠加盆地和复合盆地;多种构造-热体制下盆地演化的残留盆地动力学类型有伸展隆起下局部沉降引起的残留盆地、推覆褶皱隆起引起的残留盆地、俯冲至局部碰撞引起的残留盆地及周边抬升隆起引起的残留盆地。关于盆地形成与演化的地球动力学机制包括:岩石圈的板块作用机制,岩石圈的深部作用机制以及岩石圈的表生作用机制。岩石圈的板块作用机制包括板块伸展、挤压和剪切作用;岩石圈的深部作用机制包括软流圈与超级地幔柱对岩石圈的作用,尤其是壳幔作用;岩石圈的表生作用机制也很重要,包括盆地的重力作用、大气作用、海洋作用和生物作用。通过本文的研究,可以为研究整个岩石圈演化、壳幔作用、地球动力学过程以及成藏成矿机制奠定重要理论基础;同时,对于沉积盆地矿产资源、能源资源、水资源勘探和开发,以及灾害防治和环境保护也具有重要应用价值。

Dynamic types of basin formation and evolution and its geodynamic mechanisms

On the basis of the existing researches of basin worldwide and basin analysis, this paper establishs the new principle of basin classification, discusses the dynamics types of basin evolution, and further expounds the geodynamics mechanism of basin evolution and expansion from three aspects of the lithosphere plate, deep lithosphere and lithosphere supergene action. The new classification principle is ensured to be systematic, scientific, and practical. According to our research, the basin classification should first consider the geodynamic environment of basin formation and evolution, including the lithosphere plate and deep effect environment and lithosphere supergene action, and then take all kinds of geologic function and the dynamic process of basin formation and evolution, such as tectonic setting(extending, compressing and shear process), thermal effect and gravity division into account for main classification, finally, the different nature of the basin basement and crustal types, as continental crust, oceanic crust or transitional region basin, as well as the history of basin sedimentary filling and tectonic palaeogeography, evolution of the small class segment such as marine sedimentary basin, continental basin, and transitional facies basin should be considered for the further sub-classification. In the process of basin formation and evolution, the basic dynamic type of basin includes: The prototype basin evolution under a single tectonic or thermal system, the prototype basin evolution under a single gravitation system, the superimposed basin evolution under multiple thermal tectonic systems and the residual basin evolution under multiple tectonic thermal systems. In a single tectonic or thermal system, from lithosphere plate and mantle and crust action, prototype basin dynamic types have extension basin(intracontinental extension basin, continental extension basin, oceanic extension basin and back-arc extension basin), the flexural basin(back-arc flexural basin, peripheral torsion flexural basin and intracontinental flexural basin), strike-slip basin(strike-slip extending basin and strike-slip compressing basin) and craton basin(craton retreating basin, craton expanding basin and craton migrating basin).The superimposed basins under multiple tectonic thermal systems include the superimposed basin and composite basin, while the residual basins under multiple tectonic thermal systems includes the residual basin caused by extend uplift under local subsidence, fold-thrust uplift, underthrust to part impaction uplift, peripheral uplift. The earth dynamics mechanism of basin formation and evolution include the lithospheric plate mechanism, lithospheric deep mechanism and supergene action mechanism of the lithosphere. Lithospheric plate mechanism includes a plate extending, compressing and shearing action while lithospheric deep mechanism include the effect of asthenosphere and super mantle plume in the lithosphere, especially the crust-mantle. Lithospheric supergene action mechanism is supposed to be most important, including effect of gravity of basin, atmosphere, ocean and biology. This study could provide the important theoretical foundation for the evolution of the lithosphere, crust-mantle action, and the earth dynamics process and accumulation metallogenic mechanism, and could be valuable for for the mineral resources, energy resources and water resources exploration and development of sedimentary basin, and disaster prevention and environmental protection as well.