昆明理工大学韩润生团队研究了川西南大梁子铅锌矿床黑色/断裂带构造岩矿化蚀变岩相分带规律及形成机制。相关论文于2025年3月31日发表在《地球化学学报》杂志上。

大梁子铅锌矿床是川滇黔铅锌成矿区的典型矿床之一，与成矿区NWW—近EW走向滑动构造作用下形成的黑色断裂带构造体系有着密切的成因关系。R1黑色/断裂带与成矿关系密切；然而，该构造体系的控岩控矿作用机制尚不清楚。

通过对R1黑色/断裂带构造岩矿化蚀变岩相的详细分析，构造岩矿化改变岩相带可从铅锌矿化中心（F5、F100和其他断层）向外依次分为四种类型，即（1）角砾状和网状铅锌矿化复合角砾岩相带；（2） 铅锌矿化简单角砾岩和碎裂岩相带网状；（3） 脉状黄铁矿-硫化物-白云质碎裂岩相带；（4） 细脉方解石黑色碳化白云岩相带。

随着成矿流体的演化，均一化温度从区域1降低到区域4；盐度从区域1增加到区域2，然后从区域3和4减少。流体密度总体变化不大。从1区到4区，Zn、Pb、Cu、Ga、Ge、Cd、Ag和其他成矿元素的含量、Zn/Pb比和CaO/MgO摩尔比逐渐降低，REE分馏、钙化、硅化和黄铁矿化逐渐增强。这一系列变化是走滑构造底辟作用（隐爆作用）和黑色/断裂带的产物，其中由NWW近似EW走向的右旋剪张断层F1和F15衍生的二级构造控制着角砾岩和网状铅锌矿化复杂角砾岩相带以及网状铅锌矿化简单角砾岩和碎裂岩相带。因此，该研究建立了黑色/断裂带构造岩矿化蚀变岩相的分区模式，并提出区域1和区域2提供了重要的勘探标准。

附：英文原文

Title: The zoning rule and forming mechanism of tectonite-mineralized alteration lithofacies of black/fracture zone of the Daliangzi Pb–Zn deposit in southwest Sichuan in China

Author: Li, Lingjie, Han, Runsheng, Wu, Jianbiao, Feng, Zhixing

Issue&Volume: 2025-03-31

Abstract: As one of the typical deposits in the Sichuan-Yunnan-Guizhou Pb–Zn metallogenic province, the Daliangzi Pb–Zn deposit has a close genetic relationship with the structural system of the black/fracture zone formed under the action of the NWW-approximately EW strike-slip structures in the metallogenic province. The R1 black/fracture zone has a close relationship with ore forming; however, the mechanism of the rock- and ore-controlling action of the structural system remains unclear. Based on a detailed analysis of the tectonite-mineralized alteration lithofacies of the R1 black/fracture zone, the tectonite-mineralized alteration lithofacies zones can be divided into four types in succession outward from the Pb–Zn mineralization center (F5, F100, and other faults), i.e., (1) the brecciated and stockwork-like Pb–Zn mineralization-complex breccia facies zone; (2) the stockwork-like Pb–Zn mineralization-simple breccia and cataclasite facies zone; (3) the veined pyrite–sulfide–dolomitic cataclasite facies zone; (4) the fine-veined calcite-black carbonized dolomite facies zone. With the evolution of the ore-forming fluid, the homogenization temperature decreases from Zone 1 to Zone 4; the salinity increases from Zone 1 to Zone 2 and then it decreases from Zones 3 and 4. The fluid density shows little change overall. The contents of Zn, Pb, Cu, Ga, Ge, Cd, Ag, and other metallogenic elements, Zn/Pb ratio, and CaO/MgO mole ratio decrease gradually from Zone 1 to Zone 4, and the REE fractionation, calcilization, silicification, and pyritization enhance gradually from Zone 1 to Zone 4. This series of changes is the product of diapirism (cryptoexplosion) of strike-slip structures and the black/fracture zone, among which the second-order structures derived from NWW-approximately EW-striking dextral shear-tension faults F1 and F15 control the brecciated and stockwork-like Pb–Zn mineralized complex breccia facies zones and the stockwork-like Pb–Zn mineralized simple breccia and cataclasite facies zones. Therefore, this paper establishes the zoning mode of tectonite-mineralized alteration lithofacies of the black/fracture zone and proposes that Zones 1 and 2 provide important prospecting criteria.

DOI: 10.1007/s11631-025-00773-y

Source: https://link.springer.com/article/10.1007/s11631-025-00773-y