Geology And Genesis Of The Iion Deposit In Kawa Area,Western Sector Of The North Qilian Mountains

The iron ore concentration area in Kawa area is belonged to the polymetallic metallogenic belt in the west sector of north Qilian mountains,and is another major breakthrough of sedimentary-metamorphic iron deposits' surveying work after Jingtieshan iron deposit.In this area,the Kawa,Shuanglong and Taligangou iron deposits are the typical sedimentary-metamorphic iron deposits,occur in epimetamorphic detrital rocks of Huashugou group,Zhulongguan formation,Changcheng system,and own large scale of mineralization and huge potential resources.This thesis describes the regional ore-forming geological background,ore geology,orebody and ore characteristics in detail,uses lithologic and statigraphic correlation methods to analyze relations of these three deposits,compares the regional ore-forming characteristics with typical sedimentary-metamorphic iron deposits at home and abroad,discusses the ore genesis of the three iron deposits in this area,and then achieves the following understanding and achievement:1.The three iron deposits in this area occur in epimetamorphic detrital rocks,the orebody present layer in shape,and the distribution and occurrence of orebody are controlled by ore-hosting strata.The main ore types of Kawa and Shuangtie iron deposits are hematite and magnetite occurring in slate,and they all belong to low grade iron deposit.2.Through geochemical analysis of the ore-hosting strata in Kawa iron deposit,volcanic rocks and metamorphic basement in this area,it is basically confirmed that the major metallogenetic matters came from the crust,and were influenced by volcanism.The iron deposits of this area belong to sedimentary-metamorphic iron deposit,and own the same genesis with the Jingtieshan iron deposit.3.By the stratigraphic correlation and genesis discussion,the Kawa and Shuanglong iron deposit are belonged to the same deposit formed in the same sedimentary event,and then moved to different place because of the succeeding tectonic processes.The Shuanglong iron deposit is more intact,while the volcanic rocks under Kawa and Taligangou iron deposit,and upper section of ore-hosting strata have huge resource potential.4.Through analysis of the metallogenic characteristics and genesis,distribution model of mineral phases and metallogenic model in this area are established.