摘要
贵州西北部江子山—蟒硐铅锌成矿带,位于扬子板块西南缘之菱形断块北东边界断裂南东段,经历了加里东—印支期裂陷作用和燕山期褶皱造山过程,以及海西—印支期、燕山期两次岩浆活动。铅锌成矿特征显示,本区矿化层位较多,根据矿化特征分析并差异分辨,矿床类型划分为受上司组和摆佐组主控的矿床、受垭都—蟒硐断裂主控的矿床2种,成矿金属主要来源于下伏D-C铁质、炭质、泥质碎屑岩类,但硫的来源有所不同,其中第一种类型形成机制差别在于赋矿的上司组和摆佐组地层沉积了成矿主要的硫源,并在印支期和燕山期发生富金属流体上行与地层中富硫酸盐热液的混合成矿和二次叠加,矿床成因类型为层控类型;第二种类型成矿过程为构造驱动富金属成矿流体上行至构造空间,与断裂穿层逆冲过程中下行之硫酸盐流体混合成矿,矿床成因类型为热液类型;两种类型的划分对深入研究本区铅锌成矿作用和找矿实践具有参考意义。
Jiangzimountain-Mangdong Pb-Zn Metallogenetic belt in Northwestern Guizhou Province is located at the southeast of NE-trending boundary fault of diamond fault-block in the southwest Margin of Yangtze plate.It has experienced riftogenesis in onian-Indosinian stages,orogenic process in Yanshan stages,and magmatic actions in Hercynian-Indosinian and Yanshan stages.Pb-Zn metallogenic characteristics show that this area have many mineralized layers.Based on mineralization characteristics,Pb-Zn deposits can be classified into following two types： one type primarily dominated by Shangsi Formation and Baizuo Formation;the other primarily dominated by Yadu-Mangdong fault.The metallogenic substance mainly comes from the ferruginous,carbon-base and pelitic clasolite in the lower strata（D-C）,but the source of sulphur is different.One genetic type is stratabound ore deposit whose formation mechanism is different from the other one.As the source of sulfur,it is sedimented in Shangsi Formation and Zuobai Formation.Mixed mineralization and two superimposed between high-metal fluid and high-sulfates thermal fluid occurred in Indosinian and Yanshan stages;The other one is thermal deposit,and its mineralization processes was that tectonic movement made the high-metal fluids move up to the geological structure and be mixed with sulfate fluids from strata-dissecting fault.The division of the two kinds of Pb-Zn deposits is an important reference for further studies on mineralization and prospecting of Pb-Zn deposits in this area.
出处
《矿物学报》
CAS
CSCD
北大核心
2012年第3期432-442,共11页
Acta Mineralogica Sinica
关键词
黔西北
蟒硐
构造带
矿床特征
形成机制
NW Guizhou Jiangzi mountain
Mangdong tectonic zone
geological characteristics
formation mechanism
