## 6 Conclusions  
1. By measuring the deep and surface altered rocks in the Jiawula lead-zinc deposit with SWIR spectroscopy, this study identified a total of 16 hydroxyl-bearing altered minerals. The minerals included chlorite (Fe-Mg chlorite, Mg-chlorite, and Fe-chlorite),  
Figure 11: Variations in characteristic parameters of muscovite and chlorite in ZK2115-1 (**left**) and ZK13’03 (**right**).  
sericite (muscovite, paragonite, phengite), illite (muscovite illite, paragonite illite, phengite illite), calcite, ankerite, kaolinite, and smectite. Based on the geological characteristics and TSG spectroscopic interpretation results, we established horizontal and vertical alteration zones for the deposit. The zones consisted of comb-textured quartz-illite-Fe-chlorite-carbonate veins \(\rightarrow\) muscovite-illite-chlorite-ankerite veins \(\rightarrow\) illite-smectite-chlorite veins \(\rightarrow\) chlorite-kaolinite-calcite veins.  
In borehole ZK19 (200) 13'03, Mg-chlorite was mainly distributed at the upper part of the borehole, while Fe-chlorite was mainly concentrated in the lower part. In borehole ZK20(0)1'02, no Mg-chlorite was found, and Fe-chlorite was mainly distributed in the lower part. Sericite illite was surrounded by ankerite on both sides. In borehole ZK2115-1, Mg-chlorite alteration occurred mainly in the upper part, and Fe-chlorite was concentrated in the three blocks in the upper part of the borehole.  
The crystallinity of illite, with values > 1.1, forms a distinct belt extending from north to west, with two anomalous centers concentrated at the 1' and 5'-9' lines. The crystallinity of chlorite, with values > 3.0, shows two anomalous centers concentrated at the 9' and 17' lines. So, the hydrothermal centers of the Jiawula mine are probably located in the deep areas where the Al-OH absorption peak wavelength of illitization (<2206 nm) is small with a high crystallinity index (>1.1) and where the Fe-OH absorption peak wavelength of chloritization (>2254 nm) is high with an even higher crystallinity index (>3.0).  
By delineating the hydrothermal centers and showing their spatial relationship with the known ore bodies, we established a lithological alteration-high-grade mineralization correlation with the diabase + andesite-Fe-chlorite + illite. In future exploration, we recommend paying attention to the distribution of deeply fractured chloritized diabase because these geological characteristics are often linked to mineralization.  
Conceptualization, L.W., W.F. and Z.Y.; methodology, L.W. and G.G.; software, L.W., Z.L. and G.G.; validation, L.W.; formal analysis, L.W. and D.W.; investigation, L.W., Z.L. and G.G.; writing--original draft preparation, L.W., Z.Y. and W.F.; writing--review and editing, L.W. and Z.Y.; visualization, L.W. and Z.Y.; supervision, L.W. project administration, L.W. All authors have read and agreed to the published version of the manuscript.  
This work was financially supported by the Technology Plan Project of Yunnan Chihong Zn & Ge Co., Ltd. (Grant No. 202106 CHRDKCBD02).  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors thank the team members at CUGB for their field support, data analysis, constructive discussions, and comments.  
The authors declare that this study received funding from Yunnan Chihong Zn & Ge Co., Ltd. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.