西藏甲玛超大型斑岩成矿系统找矿方向

甲玛矿床位于西藏冈底斯成矿带，其勘查和研究程度均较高，矿体由斑岩型矿体、矽卡岩型矿体、角岩型矿体及外围独立金矿体组成，具有多元矿体结构，其成矿元素为Cu、Mo、Pb、Zn、Au和Ag，呈现多金属成矿作用特征。矿区深部及外围的勘查找矿方向一直是地质学者们关注的热点。在斑岩成矿系统理论的指导下，近年来在甲玛矿区深部及外围取得了重大找矿突破。基于最新勘查成果，甲玛矿床共探获铜资源储量超过850×10⁴ t，钼资源量达91×10⁴ t，铅锌资源量超过150×10⁴ t，伴生金储量为220 t，伴生银储量超过1×10⁴ t，达到超大型矿床规模。为进一步指导区域及外围勘查找矿工作，以甲玛矿区最新勘查成果为基础，通过对矿区钻孔的详细编录，采用地表构造蚀变填图等方法，系统解剖了甲玛矿区不同矿段的矿体地质结构，并揭示了其矿床地质特征。结合甲玛矿区新发现的主矿段深部的厚大矽卡岩矿体和外围则古朗北矿段的巨厚斑岩型矿体，分析了矿区深部及外围找矿潜力，认为甲玛矿区深部仍存在厚大矽卡岩铜钼矿体和斑岩钼矿体，应进一步加强对外围则古朗北矿段新发现的斑岩矿体、矽卡岩矿体和角岩型矿体的勘查，建立新的资源储备。此外，归纳总结有效勘查找矿方法，以期为深入探究甲玛矿床成矿作用和创建综合勘查找矿模型提供参考依据，并通过系统梳理矿区已有勘查和研究资料，总结甲玛矿床的找矿标志，为区域类似矿床的地质勘查提供重要线索，也为青藏高原斑岩成矿系统的勘查和研究工作奠定坚实基础。

Prospecting Direction of Jiama Super-large Porphyry Metallogenic System in Tibet

Jiama deposit is located in Gangdese metallogenic belt，Tibet，with high level of study and exploration.The deposit is composed of porphyry orebody，skarn orebody，hornfel orebody and peripheral independent gold orebody，as multi-unit orebody structure.The ore-forming elements included copper，molybdenum，lead，zinc，gold and silver，with ploymetallic mineralization features.In recent years，under the guidance of the theory of porphyry mineralization system，great breakthroughs have been made in the deep and peripheral mining areas.According to the latest exploration，the total copper resources （reserves） discovered in the Jiama is over 8.5 million tons，and 910 thousand tons of molybdenum，1.5 million tons of lead and zinc，220 tons of associated gold and 10 thousand tons of associated silver have been discovered in Jiama，as a super-large or giant deposit.This paper aims to reveal the regional and peripheral prospecting directions，which are useful to do the further exploration，based on the latest exploration results.The geological structure of these orebodies in different sections of Jiama，have been systematically dissected via drilling core logging and alteration and structure mapping. At the same time，combining with newly two discoveries，a large thick skarn orebody in the main ore segment and the outlying large porphyry orebody in the North-Zegulang segment，the prospecting potential in the deep and periphery of Jiama has been analyzed synthetically. The high-grade Cu （Mo） skarn orebody and low-grade Mo porphyry orebody were most important target for the deep exploration in the main ore segment，and new porphyry，skarn and hornfel orebodies would been found during the further exploration works. They were helpful to create some effective exploration methods and provided some good suggestions for further study of ore-forming process and established a comprehensive exploration model of Jiama giant deposit. In addition，after systematic analysis of existing exploration and research data，combined with the latest exploration and research results，we summarized some prospecting indicators of Jiama deposit and provided some important clues for further exploration of similar deposits in the same region.These works will construct good foundation for exploration and research of the porphyry mineralization system in the Qinghai-Tibetan plateau.