一脉状矿床成矿构造的研究

緒言热液充填脉状矿床的成矿过程往往是长期的、多阶段的,而且构造断裂的控制作用十分明显。因此,正确划分矿化阶段和查明每次成矿构造空间的规律性,对理解成矿过程和生产实际工作有着重要意义。只有当构造的间歇活动和成矿溶液的脉动作用在特定的时间和条件下统一起来时,才能形成单独的一次矿化阶段。

THE STUDY OF ORE-CONTROLLING STRUCTURES OF A VEIN DEPOSIT

This paper presents a study of the structural features of a high-temperature W-Sn vein deposit in Nanling Region, Southern China. The deposit occurs in metamorphic rock of a Caledonian folded zone and is believed to have close relation with Eanshanian granites either in age and space as well as in genesis. Ore-contral fracturing, as a result of the new stress conditions in early Eanshanian orogeny, followed the intrusion of granite and was superimposed on some older structures. Two periods may be recognized during the development of ore-bearing fissures, e. g., firstly, the initiation of fissures and, secondly, the opening and mineral filling of them. It has been proved, that the first period took place under a nearly horizontal compressive stress, and the second under a tensile stress when this area was being uplifted. It may be stated that the mineralization as a whole is essentially a process in which the compressive and tensile period alternated repeatedly. The study has also shown that, at this deposit, three stages could be derided in the course of formation of ore-bearing fissures and, on the other hand, four stages in that of ore veins. In general, deformation of each of these stages (periods) bears the carateristies of spacial volume deformation.