对遂昌治岭头金矿的几点看法

OPINIONS ON THE ZHILINGTOU GOLD MINE OF SUICHANG COUNTY

治岭头金矿在构造研究，成矿及其时代等问题，一直存在不同看法，90年代前绝大多数同志认为，该处属较老时代的金矿。目前已由不同阶段成矿到与火山热液及地下热水成矿有关的几种较年青金矿的看法。本文从构造分析、火山周边断裂矿化及矿石绝对年龄样成果，提出该区金矿与火山热液关系的密切，成矿时代属燕山晚期（相当中下白垩世）。

Through 30 years' exploration, development and study on the Zhilingtou Gold Mine, the author tried to discuss such questions as mineralization and ore - forming time by analyzing the structure 1 There are evidences indicating that the south - north directed faults belong to premineral faults.It could be seen that the faults developed in Jurassic period extend into the Creataceous strata. There are quartz dioritic porphyritic, granite porphyry and polymetallic veins in the fault zone. The quartz dioritic porphyrite is penetrated by gold and silver bearing quartz veins, indicating the later gold and silvermineralization, Besides, the unconformity interface between volcanic rocks and metamorphic rocks, the surface of the south - north directed faults and other old fault surfaces often act as the caps of ore bodies,which have great influence on mineralization.2. Magma and mineralization. The authoir classified the quartz dioritic porphyrite, granite porphyry and felsophyre as series of products from a sane magma. They are often pentrated by ore - nearing quartz veins and are precursors of gold and silver mineralization.3.The Huafengjian caldera has an area of about 1 km2. There are obviousring fractures and mineralization of different degree in the caldera, which has great influence on gold and silver mineralization.'4 The paragenetic association of minerals and the division of mineralization prerild. On basis of the geological conditions, the Sequence could be: pyrite - polymetallic sultide - gold and silver (quartz)mineralization- fluorite and calcite.5.Ore genesis and the time. The determination of ore genesis and the oreforming tine should be relied on accurate geological data. The Zhilingtou Gold Mine is mainly controlled by arcuate faulted zone, with the are top located between F1 and F28 in east - west dirotion, the eastem side of the are in north - east direction and the western side in north - west direction. The orebodies are dustributed in echelon patterns and are products under the same stress, with local contortion due to the influence of F1 fault zone. The deposit belongs to volcanogene hydrothermal type and was formed in late Yanshanian Period (middle- lower Cretaceous system).