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以华北古陆为例,论述了地球演化史中经历的三大阶段:(1)古陆的形成阶段(4600~1800Ma):地球形成早期,以地幔对流为主导作用,到早太古宙出现初始古陆核,地幔对流驱动的地体拼贴和板底垫托是陆壳形成的主要方式;中太古宙开始出现一定规模的坳陷盆地,发育了基性火山岩碎屑岩镁质碳酸盐岩等表壳岩,同时伴随着大量中基性、花岗质岩浆活动;晚太古宙和早元古宙是陆壳形成的主要时期,并已具现今板块活动特征。地幔热柱与板块构造共同控制着地壳运动。(2)古陆稳定发展阶段(1800~250Ma):地幔热柱活动较弱,古陆主要表现为缓慢的升降运动(造陆运动)。(3)地球新活动时期(250Ma至今):地幔热柱活动进入一个新的活跃时期。岩石圈发生明显的热减薄,地幔热柱表现为多级演化,并导致盆岭系的形成。
Taking the ancient North China as an example, the paper discusses three major stages of the Earth’s evolution history: (1) The formation stage of the ancient land (4600 ~ 1800Ma): the early Earth’s formation led by the mantle convection, The paleo-continental nuclei and mantle convection-driven terrane collage and slab mat are the main forms of continental crust formation. The Middle Archean began to show some scale of depression basins and developed basic volcanic rocks-clastic rocks-magnesia carbon Acid rocks and other crustal rocks, accompanied by a large amount of basic and granitic magmatism. Late Archean and Early Proterozoic are the main periods of continental crust formation and have nowadays the characteristics of plate tectonics. Together, the mantle plume and plate tectonics control crustal movement. (2) Stable development stage of ancient land (1800-250 Ma): Weak mantle plume is weak, and ancient land mainly shows slow ascending and descending movement (land-making movement). (3) Earth’s new activity period (250Ma to now): The activity of mantle plume enters a new active period. Significant thermal thinning occurs in the lithosphere, and the mantle plume shows multi-level evolution and leads to the formation of basin-ridge systems.