福建紫金山陆相火山岩型Cu－Au矿田区域地质地球化学异常结构模式

矿床模式是目前国内外的研究热点之一。各种各样的地质找矿模型与模式层出不穷,也建立了一些地球化学找矿模型。但是它们基本上是建立在矿床原生晕基础上的,以区域地球化学资料为基础建立的矿床或矿田区域地球化学异常模式尚属少见。本文以矿田为基础研究单元,以1:20万区域化探扫面资料为基础,从矿田的区域地质背景特征和39种元素的正、负区域地球化学异常分布规律出发,研究了成矿的区域地质环境和地球化学环境。发现成矿元素异常组合、指示元素异常组合和成矿环境元素异常组合的空间分布,在矿田上具有独特的结构特征,提出了异常结构模式的概念。进而总结出了紫金山矿田的区域地质地球化学异常结构模式。

REGIONAL GEOLOGICAL-GEOCHEMICAL ANOMALY STRUCTURAL MODEL OF THE ZIJINSHAN CONTINENTAL VOLCANIC COPPER-GOLD OREFIELD

Metallogenic model of ore deposits constitute one of the problems that have aroused much interest in research work. There exist a great variety of geological ore-prospecting models and patterns as well as a number of geochemical ore-prospecting models. Nevertheless, these models are generally established on the basis of primary halos of ore deposits. whereas regional geochemical anomaly models of ore deposits or orefields established on the basis of regional geochemistry are relatively rare. With the ore field as the basic research unit and the 1: 200000 regional geochemical data as the basis, the present paper has studied regional geological and geochemical environments for mineralization from regional geological setting of the orefield as well as distribution regularity of positive and negative regional geochemical anomalies of 39 elements. It has been discovered that the spatial distribution of anomaly associations of ore-forming elements, anomaly associations of indicator elements and anomaly associations of elements in metallogenic environments exhibits unique structural characteristics in the orefield. On such a basis, the present paper has put forward the concept of anomaly structural model and, furthermore, the regional geological-geochemical anomaly structural model of the Zijinshan orefield.