1篇
您的检索式：作者名="DONGChuanwan"
|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Discovery and Genetic Mechanism of Basic Granulite in the Altay Orogenic Belt, Xinjiang, NW China显示文摘Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in thc Wuqiagou area, Fuyun County in the Altay orogenic belt, Northwest China. It is composed mainly of hypersthene, augite, basic plagioclase, amphibole and brown biotite. Its mineral compositions of amphibole and biotite are rich in Mg/(Mg+Fe2+) and Ti. Geochemically, the AG is enriched in Mg/(Mg+Fe2+) and A12O3, and poor in CaO, with depletion of U, Th, K and Rb contents. Furthermore, geochemical data reflect that the protolith of the AG is igneousgenetic calc-alkalinc basalt formed under an island arc environment. The AG has ∑REE of 92.38-96.58 ppm and enriched LREE model with weak positive Eu anomaly of 1.09-1.15. In the MORB normalized spider diagram, the AG shows tridoming pattern with a strong negative Nb anomaly and medium negative P and Ti anomalies, reflecting that the AG has tectonic relation with subduction or subduction-related materials. The P-Tconditions of peak metamorphism of the AG arc 750-780°C and >0.6-0.7 GPa. Retrograde metamorphism implies that the protolith of the Altay granulite might undergo a metamorphic process along a clockwise P-T trajectory. Thereforc, thc formation and evolution of thc AG may have a genetic association with continental collision/orogeny and the AG was taken into the Late Paleozoic meta-strata by way of tectonic emplacement. | LIZilong CHENHanlin YANGShufeng DONGChuanwan XIAOWenjiao LIJiliang YEYing WANGJian | 2004 | Acta Geologica Sinica(English Edition)2004，78，1： | 2 |
您所在的机构暂未开通此部分的功能，请联系管理员