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应用颗粒锆石U-Pb法,对出露于吉林省南部通化地区的岔信子岩体、小苇沙河岩体和龙头岩体进行了侵位年代测定,确认它们形成于印支期,年龄为203-217 Ma.地质与地球化学研究显示,该时期形成的岩体主要包括石英闪长岩和花岗岩两大岩石类型,前者来自于基性下地壳或者岩石圈地幔的部分熔融;而后者来源于加厚地壳的部分熔融,且岩浆源区存在石榴石残留相.尽管上述两类岩石的源区不同,但它们具有完全一致的形成年龄.由于这些花岗岩与北侧兴蒙-吉黑造山带中的同期岩石性质差别较大,而其年代仅比大别-苏鲁超高压变质作用的年代晚10—20Ma左右,与超高压变质岩的第1次快速折返和碰撞后花岗岩的年代一致,推测其形成应与大别-苏鲁超高压碰撞造山带作用有关.
Using the granular zircon U-Pb method, the alluvial age of the Chesengzi, Xiaohe Shahe and faujasitic rock bodies exposed in Tonghua area, southern Jilin Province were measured and confirmed that they were formed during the Indosinian Period with an age of 203-217 Ma. Geological and geochemical studies show that the rock mass formed during this period mainly consisted of two major types of rocks, ie, quartz diorite and granite. The former came from the partial melting of the underlying lower crust or lithospheric mantle. The latter came from The thickened crust is partially melted and there is a residual garnet phase in the magma source zone. Although these two types of rocks have different source regions, they have exactly the same age of formation. Because these granites are associated with the northern Xinghuo-Jimi orogenic belt Of the same period of rock properties vary greatly, and its age only Dabie - Sulu ultra-high pressure metamorphism of the age of about 10-20Ma, and ultrahigh pressure metamorphic rock after the first rapid re-collision and granite after the collision age, speculated that the formation Should be with the Dabie - Sulu EHV collision orogenic belt related.