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松辽盆地基底主要由浅变质～未变质的古生代地层、花岗岩和片麻岩组成，岩相学研究表明所谓的片麻岩应为变形的花岗质侵入体．锆石 Ｕ－Ｐｂ同位素定年结果显示，这些花岗岩形成于晚古生代（（３０５± ２）Ｍａ）和晚中生代（（１６５± ３）Ｍａ），且基本不含古老锆石残留，表明松辽盆地不具备大规模前寒武纪结晶基底．
The basement of the Songliao Basin is mainly composed of Paleo-metamorphic to unmetamorphic Paleozoic strata, granite and gneiss, and petrography shows that so-called gneiss should be deformed granitic intrusions. The zircon U-Pb isotopic dating results show that these granites formed in the late Paleozoic (305 ± 2 Ma) and late Mesozoic (165 ± 3 Ma), and basically did not contain the ancient zircon residue, indicating that the Songliao Basin With large-scale pre-Cambrian crystallization of the substrate.