| Granite tectonics is one of the important realms of structure geology. The study on structural pattern of plutons can reveal more information of regional deformation, provide us detailed information of structural evolution of orogenic belts, define the emplacement mechanism of plutons, and help to investigate the feedback relationship among magmatic activities, tectonism and deep processes. The investigation of structural deformation of granites is one of the links between granites research and continental dynamics research.The discovery of coesite and microdiamond in Dabie mountain makes the ultrahigh pressure metamorphic belt in Dabie the hot spot for Earth dynamics. Substantial achievements have been made at such aspects as structural geology, geochemistry, mineralogy, petrology and stratigraphy et al. on the research of ultrahigh pressure and orogen. However, debates still exist on some important questions, such as "in situ" or "foreign" metamorphism, the depth of subduction and the exhumation mechanism and process of formation of ultrahigh pressure metamorphic rocks, and so on.This thesis has taken such measures as particular field observation, petrofabric analysis of quartz, finite strain measurements, anisotropy of magnetic susceptibility of rocks and fluid inclusions on studying metamorphic granite pluton in Shuanghe, southern of Dabie orogen to summarize the structural pattern of pluton, investigate the relationship among metamorphic granite pluton, regional ultrahigh pressure granite gneiss and ultrahigh pressure rocks, and then discuss the link between granite emplacement and evolution stages of orogenic belts. These studies provide us the evidences from structural geology for solving the question of "in situ" or "foreign" metamorphism and detailed geologic information and new constraints for evolution (especially the post-collision stage) of Dabie orogenic belts. At present, new data have been made initially at such following aspects: The mineral assemblage of metamorphic granite in Shuanghe is k-feldspar +plagioclase+quartz+biotite+hornblende+phengite+garnet+epidote+zircon+titanite et al. The metamorphic granite in Shuanghe is of S-type granite and the pluton is silicon-rich, alkali-rich, super-aluminous with ACNK of the whole rock ranging from 1.42 to 1.57, but lack of calcium. Combing with the study on zircon in metamorphic granite pluton nearby, results of calculations of mineralogical thermobarometer and characteristics of petrology, it is likely that Shuanghe pluton was formed during collision orogenesis or later by partial melting and re-emplacement of paleo-granite and concluded that the temperature and pressure conditions that the pluton experience partial melting is that T>500℃ and P=0.8GPa, and depth of emplacement is 27km±(taking the crustal pressure gradient as 30MPa/km). Petrofabric of quartz c-axis is characterized by monoclinic and triclinic symmetry but mainlytriclinic symmetry. Pole figures are largely composed of maxima, while big girdles and small girdles are not frequently seen. The maxima align along NE-SW and NW direction. Combing with analysis of foliation and lineation in pluton, it is concluded that b-axis generally forms the NE-SW maxima, while c-axis generally forms the NW maxima. The pluton is deformed by shearing or stretching along NE-SW direction and the principal compressive stress is along NW-SE. The petrofabric of quartz in the country rocks, jadeite quartzite and eclogite is similar but is different from that of quartz in the pluton by higher maxima and maxima focusing on NE-SW direction. The metamorphic granite pluton was deformed later than ultrahigh pressure rocks and its petrofabric provides us the regional stress regime after ultrahigh pressure metamorphism.The 3-D strain measurements for metamorphic granite in Shuanghe show that the principal strain plane, XY, dips towards SE with moderate dip angle and Rsxy=1.06~1.34; and the principal strain plane, YZ, dips towards NW with steep dip angle and Rsyz=1.37~2.02; while the principal st...
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