MENG Zhong-neng1, GAO Zhu1*, XIANG Xian-li1, ZHANG Qian2, WANG Da-peng2
(1. Guizhou University of Engineering Science, Bijie 551700, China;
2. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China)
Abstract: The Habo alkaline intrusion, located in the southern part of the Ailaoshan-Red River Cenozoic alkaline intrusion belt, consists of Pinshan (EP), Sandaoban (ES), Ashu (EA), and Habonanshan (EH) four units. The zircon U-Pd dating results show that these units have weighted mean 206Pb/238U ages of 36 Ma (EP), 35 Ma (ES), 37 Ma (EA), and 33 Ma (EH), respectively. A series of small- to medium-sized Au deposits, such as the Habo, Hageng, and Shapu, are distributed around the Habo intrusion, with closely temporal and spatial relationships. The results of trace and REE elements of intrusive rock and deposits show that the Habo alkaline intrusion has very similar trace element spidergrams and REE patterns to those of the Yulong and Duoxiasongduo porphyry bodies, which are located in northern part of the Jinshajiang-Ailaoshan alkaline-rich porphyry belt, indicating that they could have almost same diagenetic tectonic setting and source materials. The Habo, Hageng and Shapu Au deposits share the same source materials, which are characterized with the mixing of crust and mantle, with the Habo alkaline intrusion. The ore-forming fluids of these deposits are characterized with Cl－-rich and F－-poor, enriched thiophilic elements (Cu, Zn, Cd, Pb) and iron group elements (Co, Ni). The physicochemical conditions of mineralization of the Habo, Hageng and Shapu Au deposits are generally reduced environment. The ore-forming hydrothermal systems in the ore field, however, are relatively complicated. This complicated ore-forming hydrothermal system could be related to the hydrothermal superimposition caused by the pulsing emplacement mechanism of the Habo intrusion.
Keywords: The Habo alkaline intrusion; trace elements; REE; source materials
ACTA MINERALOGICA SINICA Vol. 39, No.5, 2019, page 507-519
