| 多宝山斑岩铜矿床成因模式 |
| |
| 引用本文： | 杜琦,陈明秀.多宝山斑岩铜矿床成因模式[J].矿床地质,1983,2(2):42-48. |
| |
| 作者姓名： | 杜琦 陈明秀 |
| |
| 作者单位： | 黑龙江省地质局第四地质队，黑龙江省地质局第四地质队 |
| |
| 摘 要： | 多宝山斑岩铜矿床位于蒙古—鄂霍茨克(古亚洲)地槽东部。矿区周围出露的地层以中古生界为主,在复背斜核部出露有奥陶系。从多宝山矿区向东南40公里为新开岭隆起,隆起呈北东东走向,上面地层多属下古生界和前古生界,而其东南广大地区地层多属石炭二叠系。多宝山矿区含矿的花岗岩体,经K-Ar法年龄测定,为292百万年,属中石炭世。由此可见,在多宝山矿床形成期间,多宝山矿区应位于正负构造单元接壤处偏隆起一侧。
|
The genetic model of Duobaoshan porphyry copper deposit |
| |
| Abstract: | The formation of Duobaoshan porphyry copper deposit is a result of the favorable combination of various geological factors. Genetically, the deposit is not only related to the magmatic and hydrothermal activities, but also governed by some stratigraphic and structural factors. According to statistics, the tops of large-sized orebodies are mostly confined to the andesite in the lower part of the Middle Duobaoshan Group. Only small orebodies with much weaker mineralization sometimes have their tops located in other strata. Average copper content of the rocks of the Duobaoshan Group is 135 ppm. The middle and lower portions of orebodies lie in the granodiorite (292 m. y.). The granodiorite and the granodioritic porphyry (283 m.y.) intruding it were of passive emplacement along the pre-existing tectonic channels. The contact surfaces between intrusions and country rocks are complex, containing a large number of pendants, xenoliths and magmatic conglomerates. The country rocks underwent various degrees of weak thermal metamorphism, and the intrusive rocks were crushed and altered to various extent everywhere. Copper mineralization occurs in a NW trending shear-compressional fracture zone, while magmatic emplacement and hydrothermal process took place during the period of the tectonic movement in the NE trending shear-compressional fracture zone. When the tectonic movement in the NE trending fractures happened, NW trending fractures opened, and then passive magmatic emplacement and hydrothermal process occurred. A quartz core is present in the middle of the deposit, From it outward there appear in sequence ovoid (quartz-perthite-) biotitization, (quartz-chlorite-) sericitization and propylitization zones. The copper mineralization occurs inside the sericitization zone superimposed on the biotitization zone. Within the (quartz-chlorite-) sericitization zone bornite seems concentrated chiefly in the central portion, from it outward bornite gradually decreases while chalcopyrite increases. But chalcopyrite suddenly disappears near the periphery, where pyrite becomes predominant. The zonation of minerals is outlined in this papen. The evolution of intrusion-alteration-mineralization is indicated in Figure A-R. |
| |
| Keywords: | |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《矿床地质》浏览原始摘要信息 |
| 点击此处可从《矿床地质》下载免费的PDF全文 |
|
