东天山古弧盆体系成矿规律与成矿模式

东天山是中亚增生型造山带的重要组成部分,随古亚洲洋的形成、演化和消亡,发育了东天山古生代弧盆体系。基于前人对东天山古生代构造演化与成矿规律的大量研究,针对以往研究相对薄弱的早古生代构造演化与成矿,本文重点论述了以卡拉塔格矿集区为代表的早古生代构造-岩浆-成矿研究新进展,从而进一步探讨了东天山古弧盆体系古生代构造演化与成矿规律。本文将东天山古弧盆体系划分为大南湖-头苏泉成矿带和阿奇山-雅满苏成矿带,又将前者划分为卡拉塔格成矿亚带和小热泉子-土屋成矿亚带;总结出其成矿具有VMS成矿系统与斑岩成矿系统共存、多种矿化类型叠加的特征;区域共发育两次大规模成矿事件,且均与大规模火山-侵入岩浆活动有关,进而构建了东天山古弧盆体系区域成矿模式;并指出东天山古生代弧-盆多方向、多期次的转换是导致该体系内VMS-斑岩型矿床共存、叠加成矿发育的主因。

Metallogenic regularity and metallogenic model of the paleo arc-basin system in eastern Tianshan

The eastern Tianshan is an important part of the accretionary Central Asian Orogenic Belt (CAOB), where the eastern Tianshan Paleozoic arc-basin system was developed during the formation, evolution and closure of the Paleo-Asian Ocean. Based on a large number of the predecessors'' studies on Paleozoic tectonic evolution and metallogenic regularity of the eastern Tianshan, and aimed at the relatively weakness upon researches in the past about Early Paleozoic tectonic evolution and metallogenesis, this paper focuses on the new progress of the Early Paleozoic tectonic-magmatic-metallogenic studies in the Kalatage ore cluster area, and further discusses the Paleozoic tectonic evolution and metallogenic regularity of the paleo arc-basin system of eastern Tianshan. In this paper, the Paleozoic arc-basin system of the eastern Tianshan is divided into two metallogenic belts of Dananhu-Tousuquan and Aqishan-Yamansu, while the former is further divided into the Kalatage and the Xiaorequanzi-Tuwu metallogenic sub-belts. It is concluded that this paleo arc-basin system has coexistence of VMS and porphyry metallogenic stystems. Multiple types of superimposed mineralization are widely developed in these systems. Tectonically, two large-scale metallogenic events have been developed, and both of them are related to large-scale volcanic-intrusive magmatic activities. Finally, a regional metallogenic model of the paleo arc-basin system of the eastern Tianshan is constructed, in which we propose that the multi-directional and multi-stage transformation of Paleozoic arc and basin in the eastern Tianshan is the main reason for the coexistence of VMS-porphyry deposits and superimposed mineralization in this system.