辽宁省本溪北台铁矿的构造控制规律——运用构造解析解决找矿问题的一个实例

本溪北台铁矿为产于太古宙鞍山群中的BIF.矿体形态、产状均甚复杂.构造解析表明,这种复杂性是由于经受了至少三期构造变形所引起的.本文在详细剖析各期构造变形及其对铁矿体的控制规律的基础上,提出了深部找矿方向,已得到实践验证,经济效果显著.

STRUCTURAL CONTROL OF THE IRON-ORE DEPOSITS IN BEITAI IRON-ORE MINE, BENXI, LIAONING PROVINCE-AN EXAMPLE OF USING THE ANALYTICAL METHOD TO SOLVE PROBLEMS OF MINERAL PROSPECTING

Structural complexity in the Archaean rocks in Beitai area results mainly from polyphase deformation during the Archaean tectonic cycle by which several sets of structural elements with different geometrical forms and directions were produced. By comparing with regional structural sequence, three pronounced phases of deformation took place in rocks of this area, i.e. the D₁, D₃ and D₄ deformation. Folds of successive episodes interfere different patterns amenable to be distinguished in domains.Repetition of ore bodies by isoclinal folds (F₁) causes immense thickness of mined parts and enrichment of iron in axial portions of folds. Change in attitude of ore bodies from dipping to northeast at the surface to southwest in deep has been made out to be due to F₃¹ s superimposition. It is also confirmed by using the method of single inclined drilling hole which was firstly proposed by one of the writers in 1973. This discovery is noteworthy and of fundamental significance in enlargement of ore reserve to this Mine.