THE FRAMEWORK OF THE DEEP FRACTURES IN LIAONING AND THEIR SIGNIFICANCE FOR ROCK AND ORE CONTROL

The deep fractures in Liaoning may be grouped into the E-W-,NE-and NNE-trending systems.The E-W-trending deep fracture system controlled the evolution of the early Proterozoic geosyncline of Liaoning and restricted the deposition of the covers from the middle Proterozoic to early Mesozoic in Liaoning.The NE-trending deep fracture system took shape in the early Mesozoic and underwent strong activity from the late Mesozoic to Cenozoic. The NNE-trending deep fracture system of late Mesozoic to Cenozoic age was superimposed upon the two above-mentioned deep fracture systems and played a decisive role in controlling the development of the Meso-Cenozoic geological structures in Liaoning.The deep fracture belt has an obvious controlling effect on rock and ore formation,and six main tectonic metallogenetic belts may be distinguished. The authors consider that after the Tancheng-Lujiang fracture extends into Liaoning,the Hurdle,Tieling and Liaohe deep fractures successively exhibit the features of different stages of evolution of the Tancheng-Lujiang fracture. Therefore,the Tancheng-Lujiang fracture is a disintegrated and superimposed fractuze system in Liaoning.