| Petrogenesis of Mesozoic High-Mg Diorites in Western Shandong: Evidence from Chronology and Petro-geochemistry |
| |
| 作者姓名： | Yang Chenghai College of Earth Sciences Jilin University Changchun China Bureau of Geology and Mineral Resources of Shandong Province Jinan China Xu Wenliang* Yang Debin College of Earth Sciences Jilin University Changchun China Liu Changchun Bureau of Geology and Mineral Resources of Shandong Province Jinan China Liu Xiaoming Hu Zhaochu Key Laboratory of Continental Dynamics Northwestern University Xi'an China |
| |
| 作者单位： | Yang Chenghai College of Earth Sciences，Jilin University，Changchun 130061，China; Bureau of Geology and Mineral Resources of Shandong Province，Jinan 250013，China Xu Wenliang* Yang Debin College of Earth Sciences，Jilin University，Changchun 130061，China Liu Changchun Bureau of Geology and Mineral Resources of Shandong Province，Jinan 250013，China Liu Xiaoming Hu Zhaochu Key Laboratory of Continental Dynamics，Northwestern University，Xi'an 710069，China |
| |
| 基金项目： | 中国科学院资助项目，the Key Laboratory of Continental Dynamics |
| |
| 摘 要： | TheeasternNorthChinacraton(NCC)isanat urallaboratoryforthestudyoftheformationandev olutionaryhistoryoftheMesozoiccontinentallitho sphereduetoitsparticulartectonicpositionandthe Mesozoicigneousrockswidelyoccurringonit(Wangetal.,2005;Gaoetal.,2004;Peietal.,2004;Xu etal.,2004a,b,c,2003a,b,2000,1999;Zhanget al.,2002;Griffinetal.,1998;MenziesandXu,1998).However,thehigh Mgdioritesinwestern Shandonghaveimportantimplicationsinthestudyof therelationshipbetweenMesozoicmagmatismand thenatureoftheli…
|
Petrogenesis of Mesozoic High-Mg Diorites in Western Shandong: Evidence from Chronology and Petro-geochemistry |
| |
| Yang Chenghai College of Earth Sciences,Jilin University,Changchun ,China, Bureau of Geology and Mineral Resources of Shandong Province,Jinan ,China Xu Wenliang* Yang Debin College of Earth Sciences,Jilin University,Changchun ,China Liu Changchun Bureau of Geology and Mineral Resources of Shandong Province,Jinan ,China Liu Xiaoming Hu Zhaochu Key Laboratory of Continental Dynamics,Northwestern University,Xi'an ,China.Petrogenesis of Mesozoic High-Mg Diorites in Western Shandong: Evidence from Chronology and Petro-geochemistry[J].Journal of China University of Geosciences,2005,16(4). |
| |
| Authors: | Yang Chenghai Xu Wenliang Yang Debin Liu Changchun Liu Xiaoming Hu Zhaochu |
| |
| Abstract: | The high-Mg diorites, widely occurring in western Shandong, have important implications in the study of the relationship between the Mesozoic magmatism and the nature of the lithosphere and its thinning period in the eastern North China craton (NCC). The Tietonggou and Jinling intrusions are typically representatives. LA-ICP-MS zircon U-Pb dating, major and trace element and Sr-Nd isotopic compositions of the Mesozoic intrusive rocks from western Shandong, eastern China, were analyzed. The weighted mean 206Pb/238U ages from LA-ICP-MS zircon U-Pb dating results for early norite-diorite, late pyroxene-diorite from the Tietonggou intrusion and biotite-diorite from the Jinling intrusion are (131.4±4.9) Ma(n=15), (134.5±2.3) Ma(n=13), and (132.8±4.2) Ma(n=12), respectively, implying that they were formed in the Early Cretaceous. The weighted mean 207Pb/206Pb ages for round zircons from late pyroxene-diorite in the Tietonggou intrusion is (2 513±54) Ma(n=8), suggesting that the basement of the North China craton should exist in the research area. The high-Mg diorites are characterized by enrichment in MgO, Na2O, and light rare earth elements (LREE), and they are poor in heavy rare earth elements (HREE) and high field strength elements (HFSE), being similar to adakite. The existence of the mantle peridotite xenoliths with a high-Mg feature for these intrusive rocks implies that their primary magma should be derived from the upper mantle. However, Sr-Nd isotopic compositions (Isr: 0.704 75-0.707 15; εNd(130 Ma) values: -3.95 to -13.30), depletion in HFSE, and the occurrence of Archean inherited zircons suggest that crustal materials could be involved in the derivation of the primary magma. The compositional difference between the diorites from the Tietonggou and Jinling intrusions could be attributed to those of magma sources and degrees of partial melting. The Early Cretaceous high-Mg diorites are considered to have been formed by the mixed melting of the delaminated lithosphere (lithospheric mantle crust) and asthenosphere, based on their geochemistry, the mantle-derived xenoliths, and the Early Mesozoic lithospheric evolutionary history of the eastern North China craton. |
| |
| Keywords: | high-Mg diorite chronology geochemistry Mesozoic western Shandong |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
|
