安徽贵池地区燕山期岩浆岩与铜金钼成矿关系:来自地质-地球化学-地球物理证据

安徽贵池地区是长江中下游成矿带的重要组成部分,区内金、银、铜、钼、硫等矿产资源丰富。系统研究了贵池地区地质、岩浆岩、地球化学-地球物理等特征与金银多金属矿床的成矿关系,对抛刀岭金矿、乌石金及多金属矿、朱家冲金矿、铜山铜矿等多金属矿进行详细分析,总结各岩体的地球化学属性,并对贵池地区斑岩型矿床进行了重点研究,分析其成矿专属性。将贵池地区成岩成矿时间划分为两期:第一期是140 Ma左右的岩浆活动及成矿作用,为早白垩世(燕山早期),主要与铜金矿床有关;第二期是125 Ma左右的岩浆活动及成矿作用,主要与钼(铜)矿床(化)有关。这两期岩浆活动及成矿作用包括高钾钙碱性、碱性两个成岩系列,岩石类型以中酸性—酸性花岗闪长岩、花岗岩为主,与长江中下游地区其他矿集区的成矿作用类似。将地质标志、地球物理标志以及地球化学标志结合,建立了该区找矿标志,从而有助于区内金、银(铅锌)及铜钼等金属矿成矿理论的丰富及成矿规律的认识,为区内找矿突破提供科学依据。

Metallogenic Relationship Between Yanshanian Magmatic Rocks and Cu-Au-Mo Deposits in Guichi Area of Anhui: Evidences from Geological-geochemical-geophysical Characteristics

Guichi area in Anhui is one of the most important Cu-Au deposits in the Middle-lower Yangtze metallogenic belt, which is rich in gold, silver, copper, molybdenum, sulfur and other mineral resources. The metallogenic relationships among the geology, magmatic rocks, geochemistry-geophysics, other geological features and Au-Ag polymetallic deposits were systematically studied; Paodaoling gold deposit, Wushi gold and polymetallic deposits, Zhujiachong gold deposit, Tongshan Cu-Au deposit were analyzed in detail, and the geochemical characteristics of related magmatic rocks were summarized; furthermore, the porphyry types of deposits and the metallogenic specialization were analyzed particularly. Together with the published chronological data, the diagenetic mineralization in Guichi area can be divided into two phase. One is at ~140 Ma, the Early Cretaceous (Early Yanshanian), which is related to Cu-Au deposit; another is at ~125 Ma, related to Mo (Cu) deposit (mineralization). The two phases include high-potassium calc-alkaline and alkaline series, mainly as intermediate acid-acid granodiorite and granite, similar to other ore clusters in the Middle-lower Yangtze metallogenic belt. Combined with geological, geophysical and geochemical information, the prospecting characteristics of ore exploration are established. Moreover, it is helpful to deepen the metallogenic theory of metals such as Au, Ag(Pb-Zn) and Cu-Mo, and the metallogenic regularities, providing a scientific basis for ore prospecting breakthrough in Guichi area.