陕西旬阳地区志留系铅锌矿带成矿地球化学特征及物理化学条件

Metallogenic Geochemistry and Physico-Chemical Conditions of Silurian Pb-Zn Mineralization in the Xunyang County,Shaanxi

陕西旬阳地区志留系铅锌矿带位于南秦岭-大别构造带中部,镇(安)旬(阳)古生代沉积盆地的南缘.该矿带东西长约100 km,南北宽10～50 km.已初步查明区内铅锌矿有中志留统双河镇组和下志留统梅子垭组含矿层位并划分为泗人沟-南沙沟、杨柳-任家沟-小沟、长沙-西营-黄石板铅锌(铜)矿带.在矿带内发现20余处铅锌(铜)矿床(点),已获铅锌资源量在10×105t以上.经研究,矿床中硫来源基本一致,属混合型;矿床中的原始铅主要来源于地壳深部或上地幔;稀土元素分析结果反映热水沉积的水源可能是混合物;成矿流体来源于建造水;成矿流体的性质属弱-中酸性介质;成矿温度主要集中在250～300oC,属低-中温热液成矿.

The Silurian Pb-Zn mineralization zone located in the southern margin of the Paleozoic Zhenan-Xunyang basin of the southern Qinling-Dabie tectonic belt is about 100 km long in EW direction and 10~50 km wide in SN direction. The early exploration has determined the Sirengou-Nanshagou, Yangliu-Renjiagou-Xiaogou and Changsha-Xiying-Huangshiban Pb-Zn zones in the middle Silurian Shuanghezhen and lower Silurian Maizita formations. About 20 Pb-Zn deposits with Pb and Zn resource reserve of 10×105 tons have been found in these zones. The study has indicated that ore deposits having basically consistent sulfur origin belong to the mixed type. The primitive Pb was mainly derived from the lower crust and upper mantle; The water source for the hot water deposit may be mixed materials; The metallogenic fluid originated from the building water that is weak-medium acidic in nature and metallogenic temperature is mainly concentrated in 250℃~300℃, belonging to epithermal ore deposit.