云南澜沧老厂多金属矿床矿石类型及其成因探讨

云南澜沧老厂是三江成矿带南段最重要的铅锌铜钼多金属矿床之一.根据不同的赋矿特征、含矿岩性、矿石构造及成矿元素将澜沧老厂多金属矿床矿石类型系统地划分为铅锌硫化矿石、铅锌氧化矿石、颗粒状含铜黄铁矿石、块状含铜黄铁矿石、夕卡岩型矿石及斑岩型钼矿石6种类型.矿体产状、微量元素地球化学、年代学证据均表明铅锌硫化矿石、颗粒状含铜黄铁矿石及块状含铜黄铁矿石为火山喷流沉积型成因（VMS型），而铅锌氧化矿石、夕卡岩型矿石及斑岩型钼矿石为斑岩热液型成因.其中，铅锌硫化矿石、颗粒状含铜黄铁矿石及块状含铜黄铁矿石的主控矿因素为地层；铅锌氧化矿石为构造；夕卡岩型矿石为岩性；斑岩型钼矿石为岩体.

DISCUSSION ON THE ORE TYPES AND GENESIS OF LAOCHANG POLYMETALLIC DEPOSIT IN LANCANG AREA,YUNNAN PROVINCE

The Laochang deposit in Lancang, Yunnan Province, is one of the most important Pb-Zn-Cu-Mo polymetallic deposits in the southern Sanjiang metallogenic belt. According to different ore-bearing characteristics, lithology, ore structures and metallogenic elements, the ore types of the study area are systematically divided into Pb-Zn sulfide ore, Pb-Zn oxidized ore, granular Cu-bearing pyrite ore, massive Cu-bearing pyrite ore, skarn-type ore and porphyry molybdenum ore. The orebody occurrence, trace element geochemistry and chronology all show that the Pb-Zn sulfide ore, granular Cu-bearing pyrite ore and massive Cu-bearing pyrite ore are of volcanic exhalation sedimentary origin (VMS type), while the Pb-Zn oxide ore, skarn-type ore and porphyry molybdenum ore are of porphyry hydrothermal origin. The main ore-controlling factor of VMS type is strata, that of Pb-Zn oxide ore is structure, that of skarn-type ore is lithology and that of porphyry molybdenum ore is rock mass.