����ԪǦп�����ʯ- - �����ͺ��ؾ�ʯ- - �����Ϳ�ʯ�е���Һ�������ʯ���ؾ�ʯ��ͬλ�غ�ϡ��Ԫ�ص���ѧ�����Ա��о�����������ʯ�� δ 13 C PDB Ϊ �� 2. 51 × 10 ^��3 �� 0. 93 × 10 ^��3 ��δ 18 O SMOW Ϊ 17. 55 ×10 ^��3 ��23. 24 ×10 ^��3 ��˵���ɿ�������̼������Դ����ϵ̼�����ҵ��ܽ�; ��ͬλ����� (0. 711 46) ���� Sr ��Դ�Կ�Դ��Ϊ���������븻�������ȵ��ϸ���м�һ��·����ױ��ʻ�ɽ���й�; ϡ��Ԫ�ؾ������Ե��� Eu �쳣 (δEu ƽ��Ϊ 1. 415)����������ʯ- -�����Ϳ�������������ѭ����±ˮ�ص㡣�ؾ�ʯ����ͬλ�� (ƽ��Ϊ 33 × 10 ^��3 ) ���и������ҷֲ���һ���ص㣬��ʾ�������Դ�ڸ�������ĵ�һ����������; Sr ͬλ�� (0. 709 18 �� 0. 709 71) ������������Դ�Ժ�ˮ��Ϊ������������Դ�ȼ���; ϡ��Ԫ�ؾ������Ը� Ce �쳣 (δCe ƽ��Ϊ 0. 255) ���� Eu �쳣 (δEu ƽ��Ϊ 1. 43)�������ؾ�ʯ- - �����Ϳ��йص���������Ǻ�ˮ (�������ˮ) �����ѭ���������ϵĽ��������ʯ- -�����Ϳ�ʯ���ؾ�ʯ--�����Ϳ�ʯ�ij�������������ѭ����±ˮ�뺣ˮ (�������ˮ) ���ֶ�Ԫ����Բ�ͬ������ϵĽ����

This paper mainly researches the geochemical characteristics of isotope and ��EE of hydrothermal dolomite and barite from dolomite- sulfide ore and barite- sulfide ore of Mayuan Pb- - Zn deposit�� The result shows that the δ 13 C PDB ��δ 18 O SMOW and 87 Sr/ 86 Sr values of dolomites are ��2. 51 ×10 ^��3 ��0. 93 ×10 ^��3 �� 17. 55 ×10 ^��3 ��23. 24 × 10 ^��3 and 0. 711 46�� respectively�� indicating the C�� O may derive from the dissolution of Sinian carbonates�� and the Sr derived from crust��such as the basement and the Paleozoic clastic rocks rich in radioactive strontium�� The ��EE patterns of the dolomites are with obvious positive anomaly of Eu (δEu average of 1. 415)��indicating the dolomite- sulfide ore- forming fluid characterised by basinal hydrothermal fluid�� The δ 34 S values (average of 33 × 10 ��3 ) of barite are enriched in 34 S and narrowly distributed��implying that the sulfur may have been derived from marine sulfate�� The 87 Sr/ 86 Sr ratios (0. 709 18 and 0. 709 71) of barite also indicate that the Sr is mainly derived from seawa- ter with little from crust�� The ��EE patterns of the barites are with obvious negative anomaly of Ce (average δCe of 0. 255) and weak positive anomaly of Eu (δEu average of 1. 43)��suggesting that the barite- sulfide ore- forming flu- id might be seawater (or meteoric water) mixed with basinal hydrothermal fluid�� The precipitation of the dolomite- sulfide ore and the barite- sulfide ore might be related to the fluid mixing of basin hydrothermal fluid and seawater (or meteoric water) at different ratios��