豫西南野獐—黑龙庙金矿成因的探讨

Study of the genesis of Yezhang-Heilongmiao gold deposit in the southwest of Henan Province

黑龙庙—野獐成矿带赋存于五朵山花岗岩体的中西部,位于五朵山岩体西成矿带内侧。本文从多种因素来探讨黑龙庙—野獐金多金属矿的成因与五朵山花岗岩体的特殊时空关联性:五朵山岩体西成矿带中的各类构造带,如断裂带、片理化带、节理以及岩体与围岩的接触带,这些应力耗散结构场所的物质活性相对较强,属地质薄弱带,矿液(成矿流体)易通过和运移。岩体中的断裂、剪切带在成矿过程中所扮演的只是导矿构造与应力释放场所;矿床矿化受限在断裂带中,热液蚀变则以接触带或断裂带为中心向两侧递减;流体作用的结果表现为Au元素丰度自接触带向岩体中心逐渐减弱至消失矿体富集与花岗岩并无成因联系,五朵山花岗岩体仅仅作为金矿的围岩而并非矿源提供者;金矿的成因中矿质源自底部的基性超基性岩基底,金矿区与加里东期五朵山花岗岩体的成因成矿在空间与时间的过程中具有阶段相关性。

The Heilongmiao-Yezhang metallogenic belt is located in the central-west part of Wuduoshan granite body.This paper has discussed the genesis of the Heilongmiao-Yezhang gold polymetallic belt and the special temporal and spatial correlation with Wuduoshan granite body from a variety of factors.In the various structural belts of the west metallogenic zones in Wuduoshan granite body,such as fault belts,schistositilization belts,joints and contact belt of granite body with the surrounding rock,the ore fluid（ore-forming fluid）is easy to pass and migrate because these stress dissipative structures have relatively strong physical activity,which are belonged to the geological weak zone.The fracture and shear zones in the granite body only play the role of the ore-guiding structures and stress-releasing places.The mineralization is limited in the fault zone,and the hydrothermal alteration is concentrated in the contact zone and fault zone and become weaker towards the two sides.The results of the fluid effect are that the abundance of Au is gradually weakened from the contact zone to the center of the granite body.There is no genetic relationship between the enrichment of the ore body and the granite.Wuduoshan granite body is only the surrounding rock of the gold mineralization and is not the gold material source.The origin of the gold mineralization is derived from the basement of the basic-ultrabasic rock.The gold mineralization has a stage correlation with the Caledonian Wuduoshan granite body genesis in the space and time process.