为分析辽河凹陷中生界物源期次，通过激光剥蚀电感耦合等离子质谱仪（laser ablation inductively coupled plasma mass spectrometry, LA-ICP-MS）对辽河坳陷中生界碎屑岩开展锆石U-Pb测年。结果表明：锆石大都发育典型的岩浆振荡环带形态且其Th/U >0.4，认为整体为岩浆成因的锆石；锆石年龄主要以中生代和古元古代早期—太古代末期占主导，其次是古生代和古元古代年龄，但不同地区年锆石龄组成内存在差异，其中大民屯凹陷主要由5组年龄组成，西部凹陷主要由4组年龄组成，东部凹陷主要由2组年龄组成。可见辽河坳陷中生界地层主要由中生界和古元古界早期—太古界末期母岩提供物源，分别对应燕山期华北板块受太平洋板块的俯冲作用以及伴随的岩浆活动和太古代末期至古元古代早期地幔柱底侵所产生的热事件；其次是古生界和古元古界，分别对应古生代华北板块北缘一系列火山活动和古元古代裂谷作用。但不同凹陷内物源组成存在差异，且母岩类型及供给强度也不同。本次测试锆石主要年龄和华北板块多次火山活动时间相吻合，可能为研究区主要物源。本次研究识别出辽河坳陷中生界碎屑岩的物源组成情况，对于进一步分析辽河坳陷物源体系、约束研究区地层年代及岩浆活动研究具有较大意义。

In order to analyze the Mesozoic provenance periods in Liaohe depression, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to investigate zircon U-Pb dating of Mesozoic clastic rocks in Liaohe Depression. The results show that most of the zircons develop typical magmatic oscillatory ring structure and the Th/U >0.4, suggesting that they are magmatic zircons as a whole. Zircon ages are dominated by Mesozoic and Early Paleoproterozoic to Late Archean, followed by Paleozoic and Paleoproterozoic ages. However, there are differences in the composition of zircon ages in different regions. Damintun sag is mainly composed of five groups of ages, the western sag is mainly composed of four groups of ages, and the eastern sag is mainly composed of two groups of ages. It is concluded that the Mesozoic strata in Liaohe Depression are mainly provided by the Mesozoic and Early Paleoproterozoic to Late Archaean parent rocks, which correspond to the subduction of the North China Plate by the Pacific Plate during the Yanshanian, the accompanying magmatic activities and the thermal events caused by the underplating of mantle plumes from late Archaean to early Paleoproterozoic. Next are the Paleozoic and Paleoproterozoic provenance, corresponding to a series of volcanic activities on the northern margin of the North China Plate during the Paleozoic and rifting during the early Paleoproterozoic. However, the provenance composition in different sags is different, and the type and supply intensity of parent rock are also different. The main age of zircon in this test is consistent with the time of multiple volcanic activities in the North China Plate, which may be the main source of the study area. The provenance composition of Mesozoic clastic rocks in Liaohe Depression is identified, which is of great significance for further analysis of provenance system in Liaohe Depression, constraint of stratigraphic age and magmatic activity in the study area.