�Ժ�����ʡ������—�ܶ������ϵ�̫ƽ���Ե¡����ϵĻ���Ⱥ��ľ��ʯ�����Ƭ�Һ������������ʯӢƬ�ҽ������ʯ LA- ICP- MS U- Pb ���꣬�������: ��ľ��ʯ�����Ƭ�����ʯ ²⁰⁶ Pb/ ²³⁸ U ��Ȩƽ����ֵ����ֱ�Ϊ 281. 8 Ma��317. 2 Ma��424. 7 Ma��529. 3 Ma; �����������ʯӢƬ�����ʯ ²⁰⁶ Pb/ ²³⁸ U ��Ȩƽ����ֵ����ֱ�Ϊ 310. 4 Ma��384. 4 Ma��484. 7 Ma; ����������õ���������ʯ 206 Pb/ 238 U ����ֱ�Ϊ 280 ±4 Ma �� 285 ±8 Ma�����⣬ǰ�˶Ի���Ⱥ�о�����������������ʱ��Ϊ�������—������������ˣ�����Ⱥʱ��Ϊ�����ͣ������ںͼ��ﶫ���ҽ��ҹ����˻���Ⱥ������Դ�����塣

This study presents LA-ICP-MS zircon U-Pb ages for garnet biotite schist from the Yangmu For- mation and biotite quartz schist from the Yanwangdian Formation of Huangsong Group��located in Taipingling uplift belt in the south of Dunhua - Mishan fault��eastern Heilongjiang Province�� Dating results show that the 206 Pb/ 238 U weighted mean age of zircons for garnet biotite schist from the Yangmu Formation were 281. 8 Ma��317. 2 Ma�� 424. 7 Ma and 529. 3 Ma��respectively. The ²⁰⁶ Pb/ ²³⁸ U weighted mean age of zircons for biotite quartz schist from the Yanwangdian Formation were 310. 4 Ma�� 384. 4 Ma and 484. 7 Ma�� The youngest zircon 206 Pb/ 238 U age gained from the two formations are 280 ±4 Ma and 285 ±8 Ma��respectively�� Furthermore��the previous research showed that the metamorphic age of Huangsong Group was the Late Permian��Early Triassic�� The above results show that the rocks within Huangsong Group formed during the Permian�� Additionally��the main sedimentary source of the Huangsong Group is dominated by the Hercynian and Caledonian magmatite��