| 略论矿区的引裂构造 |
| 点此下载全文 |
| 引用本文：.1986.A Brief Discussion On The Fracture-Leading Structure[J].Mineral Deposits,5(2):24~35 |
| Hits: 2446 |
| Download times: 1681 |
|
| |
| A Brief Discussion On The Fracture-Leading Structure |
|
|
| Abstract:The fracture Jeading structure is the structure which controls the spatial distribution of ore fields, ore deposits and orebodies. As for its significance in mineralization, there exist a variety of views. The author considers that its controlling mechanism lies in the derivation of secondary ore-hosting fissures. Therefore, it is called fracture-leading structure. The ore-forming fracture system is made up of fractures and fissures. The fracture-leading structures so far observed can be classified into four types: individual fractures two or more fractures that are approximately parallel to each other; rhombic or tetragonal structures formed by two groups of structures and the broom-like structures consisting of several fractures. The fracture-leading structures commonly occur as fractured zone, belonging to compression-shear or compression structures and formed at mineralization stage. The structural activities have a close connection with mineralization. The fillings in fractures are dominantly the breccias of wall rocks, which contain no orebody or no large orebody, but have experienced mineralization and alterations of different degrees. In the fractures and their adjacent wall rocks, several sorts of geochemical anomalies have been detected, e. g., the primary halo of metal elements or of volatile elements and the soil mercury dispersion halo. The ore-hosting fissures on the sides of the fracture appear in a single group and one direction or in numerous groups and various directions. In general, there exist three modes of occurrence: steeply-dipping fractures cutting through the layers or fissure zones, interstratal fractures or the intrastratal netted fissures. The ore-hosting fissures are usually asymmetric on both sides of the fracture, i. e., those in the upper wall is more developed than those in the lower wall. In reconnaissance and prospecting, we should first recognize the fracture-leading structure in the working district on the basis of geological and geochemical characteristics, then seek mineralization localities along this structure, especially along its upper wall. Finally, based on the metallogenic conditions, the controlling mechanism of fractures and various ore-forming indications, we can infer the type of deposits that we are likely to find, and the scale and degree of mineralization. |
| View Full Text View/Add Comment Download reader |
|
|
|
