滇西新生代与富碱斑岩有关的金矿床成矿特征和成矿条件

与富碱斑岩有关的金矿床是云南省新发现的金矿类型,典型矿床有北衙、马厂箐金矿等。它们主要分布在滇西地区的金沙江—哀牢山富碱斑岩带中及附近。金矿床的形成在时间、空间上与富碱斑岩密切相关。富碱斑岩的形成时代是喜山期,金矿化接近或略晚于富碱斑岩的形成时间。矿床围岩以中生代地层为主。本文总结该类金矿成矿特征,详细分析了与其形成相关的断裂构造、岩浆岩条件,认为该类金矿在云南具有十分重要的代表性和相当广阔的找矿前景。

ORE-FORMING CONDITIONS AND CHARACTERISTICS OF GOLD DEPOSITS RELATED TO ALKALI-RICH PORPHYRY IN THE CENOZOIC IN WESTERN YUNNAN

The gold deposits related to the alkali rich porphyry is a new discovered type of the gold deposits in western Yunnan. The typical deposits are Beiya and Machangqing gold deposits etc. They are mainly distributed along the alkali rich porphyry belt of Jinshajiang Ailaoshan area in western Yunnan. The formation of the gold deposits is closely related to the alkali rich porphyry in time and space. The age of the formation of the alkali rich porphyry is the Himalay an Epoch, and the formation of the gold deposits is close to or slightly later than that of the alkali rich porphyry. Based on summing up the ore forming features of the gold deposits, this paper analyses in detailed the ore forming conditions such as structures, magmatic rocks, country rocks and alteration. The authors consider that this type of the gold deposits are of a very important representative and fairly wide ore search prospects in Yunnan.