SHRIMP zircon U-Pb ages of Kalatongke No.1 and Huangshandong Cu-Ni-bearing mafic-ultramafic complexes,North Xinjiang,and geological implications  

作　　者：HANBaofu JIJianqing SONGBiao CHENLihui LIZonghuai 

机构地区：[1]KeyLaboratoryofOrogenicBeltsandCrustalEvolution,MOE,De-partmentofGeology,PekingUniversity,Beijing100871,China [2]BeijingSHRIMPCenter,InstituteofGeology,ChineseAcademyofGeologicalSciences,Beijing100037,China [3]KeyLaboratoryofOrogenicBeltsandCrustalEvolution,MOE,DepartmentofGeology,PekingUniversity,Beijing,100871,China//DepartmentofEarthSciences,NanjingUniversity,Nanjing210093,China

出　　处：《Chinese Science Bulletin》2004年第22期2424-2429,共6页

摘　　要：The SHRIMP zircon U-Pb dating was carried out and yielded 287±5 Ma (MSWD = 0.34) and 274±3 Ma (MSWD = 1.35) for the Kalatongke No. 1 and Huangshan- dong Cu-Ni-bearing mafic-ultramafic complexes. These ages are much more precise than pre-existing rock-mineral Rb-Sr, Sm-Nd and Re-Os isochron ages for the two complexes and constrain the timing of not only the complexes but also the magmatic Cu-Ni sulfide deposits more reliably. It is neces- sary to carefully reevaluate the previous chronological data for the complexes. The Cu-Ni-bearing mafic-ultramafic com- plexes have the ages similar to those of postcollisional A-type granites in the same area, implying that they could be related to the delamination of lithospheric mantle and upwelling and partial melting of asthenospheric mantle in postcollisional setting. Therefore, the Cu-Ni-bearing mafic-ultramafic com- plexes are a direct indicator of vertical growth of the conti- nental crustal in the Central Asian Orogenic Belt.The SHRIMP zircon U-Pb dating was carried out and yielded 287±5 Ma (MSWD = 0.34) and 274±3 Ma (MSWD = 1.35) for the Kalatongke No. 1 and Huangshan- dong Cu-Ni-bearing mafic-ultramafic complexes. These ages are much more precise than pre-existing rock-mineral Rb-Sr, Sm-Nd and Re-Os isochron ages for the two complexes and constrain the timing of not only the complexes but also the magmatic Cu-Ni sulfide deposits more reliably. It is neces- sary to carefully reevaluate the previous chronological data for the complexes. The Cu-Ni-bearing mafic-ultramafic com- plexes have the ages similar to those of postcollisional A-type granites in the same area, implying that they could be related to the delamination of lithospheric mantle and upwelling and partial melting of asthenospheric mantle in postcollisional setting. Therefore, the Cu-Ni-bearing mafic-ultramafic com- plexes are a direct indicator of vertical growth of the conti- nental crustal in the Central Asian Orogenic Belt.

关 键 词：新疆 地质研究 SHRIMP 锆石 U-Pb年代测定 铁镁质超碱络合物 岩浆 Cu-Ni-硫化矿床 

分 类 号：P562.45[天文地球—构造地质学]