陕西银洞子矿床热水沉积环境演化特征

银洞子银铅多金属矿床为一热水沉积矿床 ,后期改造作用很弱 ,基本完整地保存了原始热水沉积特征。与热水喷溢作用脉动性活动规律相应 ,金属矿物集合体条带和纹层、矿化强度在纵向上的变化具有以矿体为中心的对称性特点。热水带来的元素钠、氯表现为以矿体为中心的低—高—低趋势 ;陆源物质 (粘土矿物 )的铝和海水来源的钾、镁则表现为以矿体为中心的高—低—高趋势。 (Fe+Mn) /Ti比值也具有低—高—低变化趋势 ;岩矿石微量元素和硫同位素以及成矿介质标志在空间上也具有类似的变化特征。这些晕圈式变化特征 ,与热水活动规律一致

Evolutionary characteristics of hot-water depositional environment of Yindongzi ore deposit in Shaanxi

Yindongzi multi metal deposit is a kind of hot water depositional one. It appears a weak succeeding metamorphic change and keeps the primary hot water depositional characteristics. Corresponding to the pulsatory action rules of the hot water erupting, the vertical change of the banding, laminae and mineralizing intensity is of the symmetry characteristics which takes the ore body as a center. The elements of Na and CI from hot water show a low high low tendency from the center of the ore. In contrast, Al from continental material (mainly from clay mineral) and K and Mg from seawater appear high low high trend and center the ore body. The ratio for (Fe+Mn)/T i keeps a changing trend of low high low character. The similar changes in the space also appear in the indicators of trace elements of rock and mineral, sulfur isotope and ore media. These metamorphic characteristics correspond to the rule of hot water activities.