Geology and Ore Deposit of the Apdong Nb-Ta Mine, North Korea

북한 압동 니오븀-탄탈륨(Nb-Ta) 광산의 지질 및 광상

  • 이재호 (한국지질자원연구원) ;
  • 김유동 (한국지질자원연구원)
  • Published : 2003.12.01

Abstract

The geology of the Apdong Nb-Ta deposit, is hosted by alkali metasomatites, consist of Upper Proterozoic sedimentary rocks, alkali syenites(Hoamsan intrusive) of Phyonggang Complex(late Paleozoic to early Mesozoic), Jurassic granite and Quaternary basalt. Alkali syenites are distinguished as alkali amphibole-pyroxene syenite, alkali amphibole-biotite syenite, biotite-nepheline syenite, biotite syenite, and quartz-alkali amphibole-pyroxene syenite. Alkali metasomatites are the products of intense post-magnatic metasomatism, and form the Nb-Ta ore bodies as the belt, irregular vein and lenticular types in the southern part of Hoamsan intrusive. The ore mineralization is characterized by the occurrence of pyrochlore, zircon, and small amounts of columbite, fergusonite. magnetite, fluorite, molybdenite, ilmenite, titanite, apatite, and monazite. Pyrochlore is one of the niobium/tantalum oxides and contains substantial amounts of rare earths and radioactive elements. The compositional varieties of pyrochlore can be defined: (1) enriched in tantalum, uranium and cerium, (2) substantially tantalum- and fluorine-poor, and (3) enriched in thorium or barium. The geochemical characteristics, ore textures and mineral occurrences indicate that alkali metasomatism of the mineralizing fluid was the dominant ore-forming process.

Keywords

Apdong Nb-Ta deposit;alkali syenites;alkali metasomatism;ore minerals;pyrochlore

References

  1. Geology of Korea Foreign Languages Book Publishing House
  2. 평강 탄탈-니오비움 광상의 지질탐사보고서 강원도 탐사관리국 평강지질탐사대
  3. 조선지질구성 공업출판사