海南石碌铁矿区三棱山向斜构造的发现及其找矿意义

Discovery of Sanlengshan syncline structure in Shilu iron mining area of Hainan and its significance for prospecting

石碌矿区铁矿体主要受北一复式向斜控制,在向斜的槽部矿体厚而富,两翼薄而贫,传统的观点一致认为,该复式向斜自北向南是由北一向斜、红房山背斜和石灰顶向斜、枫树下背斜、枫树顶―鸡心坳向斜等一系列次级褶皱组成,在近几年的勘查实践和综合研究中,通过区域旋转构造应力场分析、地球物理解译、大比例尺地质填图、槽探及钻探等多种勘查手段,在北一向斜的北部新发现了一个鸡心岭背斜和三棱山向斜构造,该构造带向西与北一复式向斜复合,向北东方向撒开,是北一复式向斜北侧的一个次级褶皱构造,到目前为止,在三棱山向斜构造带内,新增铁矿石资源储量一亿多吨,取得了重大找矿突破。

The iron orebody of Shilu mining area is mainly controlled by Beiyi composite syncline.The orebody is thick and rich in the trough part of the syncline,and is thin and poor in the limbs on both sides.Traditional opinions agree that this composite syncline is composed of a series of secondary folds such as Beiyi syncline,Hongfangshan anticline,Shihuiding syncline,Fengshuxia anticline,Fengshuding-Jixin'ao syncline from north to south.During the exploration practice and comprehensive research in recent years,Jixinling anticline and Sanlengshan syncline are found in the north part of Beiyi syncline through exploration measures such as analysis of regional rotational tectonic stress field,geophysical interpretation,large-scale geological mapping,trenching and drilling.The structural belt is a secondary fold structure on the north side of Beiyi composite syncline,which is compounded with Beiyi composite syncline on the west and disperse on the northeast.Till now,a major breakthrough in prospecting works is achieved,and the new reserves of iron ore resources that found inside Sanlengshan syncline structural belt is up to more than one hundred tons.