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长江中下游及两侧的大别隆起带、扬子隆起带都是华北、扬子陆块中生代碰撞造山涉及的区域，它们可分成４个地块．对４个地块中中生代花岗岩类的区域地球化学研究，并结合其他方面资料的共同限定，证明它们都是两个陆块碰撞后（ｐｏｓｔｃｏｌｉｓｉｏｎ）区域岩石圈物质调整阶段的产物．各岩带的花岗岩类可归入早、晚两个阶段，分别具有１３７Ｍａ和１２３Ｍａ的峰值侵位年龄．早、晚阶段花岗岩类都具有Ｉ型花岗岩类的成分特征，晚阶段花岗岩类还具有Ａ型花岗岩类的成分性质；早、晚阶段花岗岩类之间具有不连续的成分演化关系．它们指示，本区早、晚阶段花岗岩类的形成是两陆块中生代碰撞后发生的两次有一定联系但又独立的岩石圈热－构造事件的产物．
The middle and lower reaches of the Yangtze River and the Dabie uplifts and the Yangtze uplifts on both sides are all involved in the Mesozoic collision orogeny in the North China and Yangtze terraces. They can be divided into four plots. The regional geochemical study of the Mesozoic granitoids in the four blocks combined with the common definitions of other data proves that they are the product of the lithosphere material adjustment phase of the postcolision region of the two land blocks. The granitoids of each rock belt can be classified into two stages of early and late phases, with peak emplacement age of 137Ma and 123Ma, respectively. The early and late granitic rocks have the characteristics of the I-type granites. The late granitic rocks also have the compositional properties of the A-type granites. The early and late granitic rocks have discontinuous composition evolution. They indicate that the formation of granitoids in the early and late stages of this area is the product of two interrelated but independent lithospheric thermo-tectonic events that occurred after the Mesozoic collision between the two blocks.