The Paleozoic sedimentary strata, fossils, geochemistry of intrusive rocks and the zircon U-Pb isotopic dating of Duobaoshan in Heilongjiang Province have been comprehensively studied. They are the marine sedimentary strata from Early Ordovician to the early Late Devonian, sea-land interbeddind sediments in the late Late Devonian, and the continental fluvial and lacustrine deposits in Early Carboniferous. It is exposed a set of granites with (300 ± 3 ～ 357 ±4) Ma in southeastern Duobaoshan marine basin. Syenite fine-grained and adamellite finegrained mylonites are post-orogenic granites, and alkali granites are post-orogenic granites in A-type. That means the Duobaoshan marine basin closed from Late Devonian, became continental sedimentary in Early Carboniferous,and in uplift and erosion stage in Late Carboniferous-Early Permian. The fact performed that the orogeny of Duobaoshan area began in Early Carboniferous, and post-organic extension continued from Late Carboniferous to Late or Early Permian.%综合研究黑龙江多宝山地区古生代沉积地层、生物化石,通过分析侵入岩岩石地球化学及其锆石U-Pb同位素测年资料,表明该地区早奥陶世至晚泥盆世早期为海相沉积地层,晚泥盆世晚期为海陆交互相沉积地层,早石炭世为陆相河湖沉积地层.多宝山海盆东南侧出霉一套年龄为(300±3～357±4) Ma的花岗岩,其中正长、二长花岗质糜棱岩为后造山花岗岩,碱长花岗岩为造山后A型花岗岩.表明多宝山海盆于晚泥盆世开始闭合,至早石炭世为陆相河湖沉积,晚石炭世一早二叠世为抬升剥蚀阶段.表现为多宝山地区于早石炭世开始造山,晚石炭世晚期或延至早二叠世发生造山后伸展作用.
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