陕西旬北地区钠长石岩与热水沉积成矿

METALLOGENESIS OF ALBITE AND HYDROTHERMAL DEPOSITION IN THE NORTH OF XUNYANG COUNTY,SHAANXI PROVINCE

近年来,旬北铅锌矿集区发现了长达近百公里的铅锌矿带及钠长石岩带,铅锌矿多顺层整合产在以志留系为主的细碎屑岩中,沉积特征明显,含矿层内热水沉积岩发育,围岩蚀变不明显,矿体下部钠长石岩发育,底板多见铁碳酸盐岩,矿层内常见热水沉积微晶硅质岩,矿石多具块状、层状、层纹状构造。热水沉积可能是铅锌矿主要成矿方式,成矿物质来自盆下深处。

In recent years, a lead-zing mineralized zone has been found approximately lOOm long in the lead-zinc concentration area of the north of Xunyang. Lead-zinc mineralization occurs in fine-grained elastic rocks mainly in the Silurian system at parallel to the stratigraphy. It is characterized by evident sedimentation, well developed thermal water sediments, un- clear wall-rock alteration, well developed albite at the bottom of orebodies and iron-cabonate found at the footwall. The ore beds appear in massive, bedded and laminated structures, in which microcrystalline siliceous rocks from hydrothermal sedimentation are common. The thermal water sedimentation may be of predominant way for the mineralization of lead-zine, and the metallogenic materials were derived from the deep of the basin.