SHRIMP U/Pb-zircon data and Nd mean crustal residence ages indicate that the lmataca Complex developed from an Archean (≥3.2Ga) continental protolith which has undergone considerable isotopic disturbance plus and juv...SHRIMP U/Pb-zircon data and Nd mean crustal residence ages indicate that the lmataca Complex developed from an Archean (≥3.2Ga) continental protolith which has undergone considerable isotopic disturbance plus and juvenile accretion during late-Archean (-2.8Ga) times. Transamazonian granulites experienced peak metamorphic conditions of 750-800℃, 6-8kbar with associated transpressive thrusting and tectonic imbrication. Geochronology on zircon, pyroxene and garnet constrains the timing of peak metamorphism at 1.98-2.05Ga. Diffusion modeling of Fe-Mg exchange between biotite inclusions and host garnet yields (near metamorphic peak) cooling rates of 50-100℃/Ma, with petrological cooling rates being generally consistent with cooling rates determined from geochronology. Combining the retrograde P-T path with cooling rates suggests that after the metamorphic peak, large portions of the lmataca Complex were exhumed from 30 to 17km at a rate of 7-2km/Ma.After this, exhumation rates progressively decreased as the rocks approached the surface. Rapid overall upliftlerosion had ceased when the rocks passed below 600-550℃ at 2.01-1.96 Ga ago. Observed variations in mineral cooling ages are interpreted as to reflect episodic differential tectonic exhumation within major fault systems. Inferred (maximum) ages of fault re-activation generally coincide with major continental accretion events in the Amazonian Craton and reflect long-term thermal evolution of the lmataca terrane, as conditioned by variable response to continued continental convergence during the Proterozoic.展开更多
Two phases of sinistral strike-slip ductile shear belts occur on the eastern margin of the Dabie orogenic belt. A muscovite ^40Ar/^39Ar plateau age of 128 Ma was obtained from mylonite in the later ductile shear zone....Two phases of sinistral strike-slip ductile shear belts occur on the eastern margin of the Dabie orogenic belt. A muscovite ^40Ar/^39Ar plateau age of 128 Ma was obtained from mylonite in the later ductile shear zone. Three muscovite samples separated from mylonites of 3 localities in the earlier ductile shear belts yield ^40Ar/^39Ar plateau ages of 192.5±0.7 Ma, 189.7±0.6 Ma and 188.7±0.7 Ma, respectively. They are interpreted as cooling ages of the earlier sinistral strike-slip deformation. It is suggested that left-lateral displacement of the Tan-Lu fault zone started in a late stage of the collision orogeny in the Dabie-Sulu orogenic belt between the North and South China plates. Therefore, the earlier Tan-Lu fault zone was syn-orogenic strike-slip tectonics. The fault zone was used again for sinistral displacement during tectonic activities of peri-Pacific regime in Early Cretaceous. It is proposed that the fault zone occurred as a transform fault during the orogenic process.展开更多
This paper gives a detailed construction of Seiberg-Witten-Floer homology for a closed oriented 3-manifold with a non-torsion Spin^c structure. Gluing formulae for certain 4-dimensional manifolds splitting along an em...This paper gives a detailed construction of Seiberg-Witten-Floer homology for a closed oriented 3-manifold with a non-torsion Spin^c structure. Gluing formulae for certain 4-dimensional manifolds splitting along an embedded 3-manifold are obtained.展开更多
Would the growing competition from Chinese industrial exports de-industrialize SoutheastAsia (SEA), returning SEA to being a primary commodity exporter? Or would there besufficient lucrative niches within the manufact...Would the growing competition from Chinese industrial exports de-industrialize SoutheastAsia (SEA), returning SEA to being a primary commodity exporter? Or would there besufficient lucrative niches within the manufacturing production chains that SEA couldspecialize in? Our simulations of the G-Cubed Asia Pacific model suggest that the fullintegration of Chinas huge labor force into the international division of labor could de-industrialize SEA. However, de-industrialization would happen only if SEA allows thedrop in FDI inflow to lower the rate of technological diffusion to its economies. If SEAcould prevent itself from falling behind technologically, it could find lucrative niches withinthe international manufacturing production chains.The policy implication is that SEA mustgive the highest priority to deepening and widening its pool of human capital by speeding upthe diffusion of new knowledge to its scientists and managers, and providing appropriateretraining programs for the displaced workers.展开更多
文摘SHRIMP U/Pb-zircon data and Nd mean crustal residence ages indicate that the lmataca Complex developed from an Archean (≥3.2Ga) continental protolith which has undergone considerable isotopic disturbance plus and juvenile accretion during late-Archean (-2.8Ga) times. Transamazonian granulites experienced peak metamorphic conditions of 750-800℃, 6-8kbar with associated transpressive thrusting and tectonic imbrication. Geochronology on zircon, pyroxene and garnet constrains the timing of peak metamorphism at 1.98-2.05Ga. Diffusion modeling of Fe-Mg exchange between biotite inclusions and host garnet yields (near metamorphic peak) cooling rates of 50-100℃/Ma, with petrological cooling rates being generally consistent with cooling rates determined from geochronology. Combining the retrograde P-T path with cooling rates suggests that after the metamorphic peak, large portions of the lmataca Complex were exhumed from 30 to 17km at a rate of 7-2km/Ma.After this, exhumation rates progressively decreased as the rocks approached the surface. Rapid overall upliftlerosion had ceased when the rocks passed below 600-550℃ at 2.01-1.96 Ga ago. Observed variations in mineral cooling ages are interpreted as to reflect episodic differential tectonic exhumation within major fault systems. Inferred (maximum) ages of fault re-activation generally coincide with major continental accretion events in the Amazonian Craton and reflect long-term thermal evolution of the lmataca terrane, as conditioned by variable response to continued continental convergence during the Proterozoic.
文摘Two phases of sinistral strike-slip ductile shear belts occur on the eastern margin of the Dabie orogenic belt. A muscovite ^40Ar/^39Ar plateau age of 128 Ma was obtained from mylonite in the later ductile shear zone. Three muscovite samples separated from mylonites of 3 localities in the earlier ductile shear belts yield ^40Ar/^39Ar plateau ages of 192.5±0.7 Ma, 189.7±0.6 Ma and 188.7±0.7 Ma, respectively. They are interpreted as cooling ages of the earlier sinistral strike-slip deformation. It is suggested that left-lateral displacement of the Tan-Lu fault zone started in a late stage of the collision orogeny in the Dabie-Sulu orogenic belt between the North and South China plates. Therefore, the earlier Tan-Lu fault zone was syn-orogenic strike-slip tectonics. The fault zone was used again for sinistral displacement during tectonic activities of peri-Pacific regime in Early Cretaceous. It is proposed that the fault zone occurred as a transform fault during the orogenic process.
文摘This paper gives a detailed construction of Seiberg-Witten-Floer homology for a closed oriented 3-manifold with a non-torsion Spin^c structure. Gluing formulae for certain 4-dimensional manifolds splitting along an embedded 3-manifold are obtained.
文摘Would the growing competition from Chinese industrial exports de-industrialize SoutheastAsia (SEA), returning SEA to being a primary commodity exporter? Or would there besufficient lucrative niches within the manufacturing production chains that SEA couldspecialize in? Our simulations of the G-Cubed Asia Pacific model suggest that the fullintegration of Chinas huge labor force into the international division of labor could de-industrialize SEA. However, de-industrialization would happen only if SEA allows thedrop in FDI inflow to lower the rate of technological diffusion to its economies. If SEAcould prevent itself from falling behind technologically, it could find lucrative niches withinthe international manufacturing production chains.The policy implication is that SEA mustgive the highest priority to deepening and widening its pool of human capital by speeding upthe diffusion of new knowledge to its scientists and managers, and providing appropriateretraining programs for the displaced workers.
