Study of the dark residual and granite in macro and micro feature , petrochemistry ,trace ele-ments and isotopic trace shew that the residual and granite have the same U Pb concord age which ex-clude the possibility that the dark residual derived from the metamorphic rock in the deep or the xenolith of wallrocks ,while the character of trace element and Sm and Nd isotopes excluded the possibility that the dark residual was the dialyse accumulation. Therefore ,the dark residual block in Douzhashan granite should be the cristalized block of mixed magma residual of midlle base magma and granite. The middle base magma should be the comprehensive products of lithosphere mantle rock melting ,mixed crustal melting and the isolation of cristalization and also the participation of asthenosphere magma. Thus lead to that Shazijiang Guanli area was the center of middle base and granite magma intrusion and mixing which controlled the lithification and uranium mineralization of Douzhashan pluton and even the whole Miaoershan complex orefield.%岩石的宏观微观特征、岩石化学、微量元素及同位素地球化学示踪研究表明，豆乍山中细粒花岗岩与包裹在其中的暗色岩块具有一致的锆石铀铅同位素年龄，排除了暗色岩块源自于深部变质岩残留体或浅部围岩捕虏体的可能性；而它们的岩石化学、微量元素及钐钕同位素特征，也排除了暗色岩块为花岗岩浆结晶析离堆积体的可能性。因此，豆乍山花岗岩中的暗色岩块应是中基性岩浆与花岗质岩浆相互混融的残留原浆结晶体。该中基性岩浆是岩石圈地幔熔融、地壳混融和分离结晶作用的综合产物，亦不排除存在软流圈地幔岩浆的直接参与。由此推断，沙子江瓜里地区是中基性岩浆与花岗质熔浆注入并发生混合作用的中心区，它控制了豆乍山岩体乃至整个苗儿山铀矿田的成岩和铀成矿。
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