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冀北康保位于华北克拉通北缘中段,北靠古亚洲洋构造域(中亚造山带).区内出露有小西沟、前孟家地、石柱梁、三老虎、新村和西五福堂等6个晚古生代花岗岩体,它们的锆石U-Pb年龄分别为260.6± 1.6 Ma、264.1±1.7 Ma、269.5±2.7 Ma、276.3±1.9 Ma、280.4±2.0 Ma和284.7± 1.7 Ma等,表明这些花岗岩体形成于早-中二叠世.晚古生代(早-中二叠世)花岗岩体在冀北康保有规律地出露,应该与古亚洲洋的构造演化有关,可能反映了古亚洲洋的俯冲消减作用具有多期次的特点.“,”The Kangbao area in Hebei Province is located in the central part of the northern margin of the North China Craton,which is bounded by the Paleo-Asian Ocean tectonic region (also known as the central Asia orogenic belt) to the north.The six kinds of Late Paleozoic granitic intrusive bodies,such as Xiaoxigou,Qianmengjiadi,Shizhuliang,Sanlaohu,Xincun and Xiwufutang,are found within Kangbao County.Zircon LA-ICP-MS isotopic dating of six different samples from the above-mentioned granitic bodies defines six weighted mean ages of about 260.6±1.6 Ma,264.1±1.7 Ma,269.5±2.7 Ma,276.3±1.9 Ma,280.4±2.0 Ma and 284.7± 1.7 Ma respectively,which is interpreted as the emplacement age of the granitic intrusive bodies and reflects the occurrence of acidic magmatism during the Early-Middle Permian.The granitic bodies from Kangbao area,Hebei Province is related to subduction of Paleo-Asian oceanic crust beneath the North China Craton during Late Paleozoic and shows the tectonic evolution of Paleo-Asian Ocean has multiperiodic characters.