早古生代斑岩铜矿形成与保存条件研究：以东天山玉带和三岔口矿床为例

中亚成矿域是独具特色的古生代成矿域，域内（尤其是中部区段）早古生代斑岩铜矿出露较少，其形成和保存条件不明，成为制约该区找矿突破的瓶颈。本项目拟选取东天山新近识别的玉带和三岔口铜矿为研究对象：1）借助岩浆单矿物（如锆石、磷灰石、角闪石）高精度原位微区结构-成分-同位素等分析技术精确刻画成矿岩浆的起源-演化过程并评价其成矿潜力；2）利用高（锆石U-Pb）-中（热液云母40Ar-39Ar）-低温（锆石和磷灰石（U-Th）/He）年代学技术来限定矿床的冷凝热历史并判别其剥蚀程度；3）综合评估矿床形成-保存条件及其找矿潜力，为深入理解区域早古生代斑岩铜矿找矿前景的制约因素提供关键区段（中段）的研究依据。该研究不仅对深化古老斑岩铜矿的成矿理论和勘查潜力认识有重要的科学意义，还对支撑区域同类矿床找矿预测有重要的实践意义。

The Central Asian Metallogenic Domain (CAMD) is a unique Paleozoic metallogenic domain in the world. However, the formation and preservation conditions of early Paleozoic porphyry Cu deposits in the CAMD (especially in the central part) are ambiguous, which have largely restricted the prospecting breakthrough of Cu deposits in this domain and merit further study. In this program, the newly recognized early Paleozoic Yudai and Sanchakou porphyry Cu deposits in the Eastern Tianshan district (Xinjiang), a key area in the central part of the CAMD, were selected for investigating the above-mentioned issue. High-precision in-situ micro structure, composition, and isotope analyses of magmatic minerals (e.g., phosphorite, zircon and amphibole) were performed to accurately depict the origin and evolution processes of the ore-hosting intrusions and further evaluate their ore-forming potentials; while zircon U-Pb, hydrothermal mica 40Ar/39Ar, and zircon/apatite （U-Th）/He chronology technologies were used to constrain the cooling and exhumation thermal histories and estimate the denudation degrees of these two deposits. These data were then combined with previous studies to provide valuable information for evaluating the mineralization and preservation conditions and prospecting potentials of the early Paleozoic porphyry Cu deposits in the critical position (i.e., the central part) of the CAMD. This study would not only help shed light on understanding of the metallogenic theory and exploration prospecting of old porphyry Cu deposits in the world, but would also have great implications for supporting further prediction of similar ore deposits in the CAMD.