Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in the Wuqiagou area, Fuyun County in the Altay orogenic belt, Northwest China. It is composed mainly o...Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in the 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 igneous-genetic calc-alkaline basalt formed under an island arc environment. The AG has ZREE 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 tri-doming 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-T conditions of peak metamorphism of the AG are 750-780℃ 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. Therefore, the formation and evolution of the 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.展开更多
In this paper ,the existence of homoclinic orbits,for a perturbed cubic-quintic nonlinear Schroedinger equation with even periodic boundary conditions ,under the geralized parameters conditions is established.More spe...In this paper ,the existence of homoclinic orbits,for a perturbed cubic-quintic nonlinear Schroedinger equation with even periodic boundary conditions ,under the geralized parameters conditions is established.More specifically,we combine geometric singular perturbation theory,with ,Melnikov analysis and integrable theory to prove the persistences of homoclinic orbits.展开更多
In this paper,the perturbed higher-order NLS equation with periodic boundary condition is considered. The existence of the homoclinic orbits for the truncation equation is established by Melnikov analysis and geometri...In this paper,the perturbed higher-order NLS equation with periodic boundary condition is considered. The existence of the homoclinic orbits for the truncation equation is established by Melnikov analysis and geometric singular perturbation theory.展开更多
文摘Altay granulite (AG), which represents the product of high-grade metamorphism in the lower crust, was newly found in the 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 igneous-genetic calc-alkaline basalt formed under an island arc environment. The AG has ZREE 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 tri-doming 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-T conditions of peak metamorphism of the AG are 750-780℃ 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. Therefore, the formation and evolution of the 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.
文摘In this paper ,the existence of homoclinic orbits,for a perturbed cubic-quintic nonlinear Schroedinger equation with even periodic boundary conditions ,under the geralized parameters conditions is established.More specifically,we combine geometric singular perturbation theory,with ,Melnikov analysis and integrable theory to prove the persistences of homoclinic orbits.
文摘In this paper,the perturbed higher-order NLS equation with periodic boundary condition is considered. The existence of the homoclinic orbits for the truncation equation is established by Melnikov analysis and geometric singular perturbation theory.
