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中文摘要：
采用原位锆石uPb定年和岩石学、地球化学综合等方法研究大别山及邻区岩浆岩的形成时代，结果表明：大别山中生代岩浆活动启动于晚侏罗世，大规模爆发于早白垩世。大别山南部的张榜花岗岩侵入体锆石LA-ICPMS年龄为150．3Ma±2．0Ma，是目前发现的大剐山最早的中生代岩浆活动记录，比早白垩世岩浆活动的峰期（～130Ma）早约20Ma，标志着大别山晚中生代巨量岩浆活动的启动。锆石的LA-MC—ICPMSHf同位素结果计算的εHf（f）为-29左右，二阶段模式年龄大约为3．05Ga，表明岩浆源区为与扬子陆核类似的大别山早前寒武纪变质基底，新生地幔物质贡献极少。年代学资料和地球化学指标的统计表明，长江中下游成矿带与大别山地区晚中生代岩浆活动在时间上是同步的，但二者岩浆性质和成因机制不同。大别山130Ma的拆沉物质主要为古老地壳物质，地壳加厚是陆陆碰撞的结果，幔源岩浆上涌出现在拆沉事件之后；长江中下游地区于150Ma因幔源岩浆底侵而使下地壳强烈加厚，引发了该下地壳于130Ma的拆沉作用，幔源岩浆的上涌贯穿整个过程。
英文摘要：
Methods of zircon dating, petrology and geochemistry are used to investigate the largescale late Mesozoic magmatism in the Dabie Mountain and adjacent areas. Results show that Mesozoic magmatism began at late Jurassic and reached its peak at early Cretaceous. Zircon LA-ICP MS U-Pb dating on the Zhangbang pluton, a granitic intrusive pluton in the southern Dabie Mountain, is 150.3 Ma±2.0 Ma, which recorded the threshold of late Mesozoic magmatism in the Dabie Mountain. It is approximately 20 million years prior to the peak （-130 Ma）. Zircon Hf analysis performed on LA-MC-ICP MS gives εHf（t） values of --29 and Hf crustal model ages of around 3.05 Ga. These old model ages are similar to those of the continental core of the South China Craton,as well as to the ages of basement rocks of Dabie Mountain. It suggests that earlier Precambrian metamorphic complexes could be the magmatic protolith. Statistic analyses of accurate chronological and geochemical data of igneous rocks show that the chronological frames of large scale late Mesozoic magmatism in the Dabie Mountain and middle-lower Yangtze River belt are the same,with different character of magma and petrogenesis. The delaminated material in the Dabie Mountain at -130 Ma mainly consists of ancient crust,which was thickened by the conti- nent-continental collision. Mantle-derived magma was not emerged until the Dabie Mountain suffered delamination. While in the middle-lower Yangtze River belt,mantle-derived magma emerged and underplated at -150 Ma, followed by the delamination of newly formed and thickened lower crust at -130 Ma. Mantle-derived magma carried out during the whole process.
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