| Duobaoshan deposit is the largest porphyry copper deposit in northern China.From north to south Sankuangogu skarn copper deposit,Duobaoshan porphyry copper deposit,Tongshan porphyry copper deposit and Zhengguang epithermal gold deposit distribute in the ore cluster.Predecessors have done a lot of research there,however which was confined to these four deposits.With previous data collection and collation,field investigation sampling,experiments and analysis,the author studys the geological characteristics of intrusions and ore bodies,characteristics of geological ages,geochemical characteristics of rocks and 1:50,000 aspects of geochemical characteristics of stream sediments and mineralization potential in the ore cluster.The main conclusions are as follows:?1?The ages of intrusive rocks in ore cluster is yielded and classified.Except for Yubaoshan with the age of 526 Ma,other Caledonian rocks yielded the age from 460 to480 Ma,which period is the most important ones for porphyry type deposits mineralization in the area.As for Hercynian rock,Jiguanshan intrusion acqurires the age at 312 Ma.Magmatism in Indosinian mainly focused on 223249 Ma.Diagenetic age of Yanshanian rock concentrate at 150184 Ma,which is an important period for Au and Cu mineralization.?2?The characteristics of intrusive rocks are as follows:As for Caledonian rocks,exceptYubaoshan rock,the remaining rock is mainly calc-alkaline-high calc-alkaline series,metaluminous to peraluminous,and they are all derived from the same mag matism;Hercynian Jiguanshan granodiorite pluton is belong to calc-alkaline series,metaluminous and right-incline of REE type.Indosinian rocks are mainly tonalite diorite-granodiorite,metaluminous-peraluminous,alkaline calcium-calcium-alkaline,right-incline pattern type and the product of the same magmatism.Yanshanian rocks are mostly granodiorite and diorite,calc-alkaline-K calc-alkaline series,and right-incline pattern type.?3?The threshold of 11 kinds of elements associated with mineralization are calculated and they are:Cu(46.9×10-6)?Au(4.2×10-9)?Ag(0.211×10-6)?As(30.8×10-6)?Sb(1.3×10-6)?Bi(0.46×10-6)?Pb(35.4×10-6)?Zn(117.1×10-6)?Sn(4.0×10-6)?Mo(2.24×10-6)?Hg(0.058×10-6).?4?The metallogenic potential areas of different level are classified.There are 5I-level mineralization potential areas:ZH-6,ZH-7,ZH-3,ZH-11 and the Zhongbaoshan intrusion.Two II–level mineralization potential areas:Yuejin intrusion and Jiguanshan intrusion. |
PDF Full Text Request