煌斑岩与金矿成矿关系探讨

DISCUSSION ON LAMPROPHYRES AND THEIR RELATIONS TO MINERALIZATION OF GOLD DEPOSITS

煌斑岩的同位素、微量元素及稀土元素特征表明煌斑岩是地幔部分熔融的产物。深断裂是其上侵地表的通道，部分煌斑岩可能是含金的岩类，但并不是矿床中金的唯一来源。岩石中金含量变化范围虽然较大，但其含量高、低并不是形成金矿床的主要因素，即使含金高，但其规模都不大，也不足以形成矿床。此外，一些煌斑岩与金矿化在形成时间上往往有所不同，在成因上当然没有直接的关系。然而，煌斑岩出露区的后期热液蚀变、矿化作用可能使金带入煌斑岩中富集成矿，也可能从煌斑岩中将金迁移到其它的有利部位成矿。由于含金量高的和含金量低的煌斑岩的上侵以及后期金矿成矿作用均受控于深断裂构造，从而，两者在空间上是密切共生的。

It is indicated on the basis of data in isotope,trace element and rare earth element of lamprophyres that they are produced from part melting of the mantle and intruded up to the surface along deep faults.Part of them could be auriferous,but not the only source of gold to form gold deposits.Although gold contents in lamprophyres are widely ranged,which are not the major factors for the formation of gold deposits.Even if the rocks are higher in content of gold,they are also not large enough in scale to form ore deposits.Moreover,some lamprophyres are often different from the gold mineralization in formation time,and there were certainly no direct relationship in genesis between them.However,the later hydrothermal alteration and mineralization could carry gold into lamprophyres to concentrate and form ore deposits,and could also carry gold into the other favourable locations from lamprophyres to form ore deposits.The upward intrusions of lamprophyres with higher or lower content of gold and the later gold mineralization are all controlled by deep faults,that is the reason why both of them without genetic relations are closely coexisted in space.