| Geodynamics and Global Climate Change are two major issues in current earth science. Built upon the plate boundaries, orogen is one of the places with most active geologic processes including tectonic movement, magmatism and metamorphism in the world, and also one of the elements with violent physical and chemical activities in the earth surface system. Therefore, the orogenic process constitutes pivotal part of the Geodynamics. This requires the orogen to be studied synthetically by multi-disciplinary, multi-sided and time-space viable methods, with the aim to investigate and understand the history of tectonics, magmatism, metamorphism and dynamics involved. Among the methods, utilizing detrital records is now proven efficient to provide new clues and new resolutions to the problems related to the orogenic evolution (such as in Himalaya Orogen). The sediments dispersed from the orogen and deposited in the adjacent basins contain lots of information pertinent to their provenance, which will become very particular as the temporal stratigraphic framework can be constrained. In this dissertation, three examples from China will be studied to show how to employ detrital records to unravel the orogenic processes and then discuss the sedimentary responses to initial collision and exhumation of HP/UHP metamorphic rocks.The studied three examples are the North Qilian Silurian sediments in the NW China, the Permian-Triassic sediments of Youjiang Basin in SW China and the Huangshi Jurassic sediments south of the Dabie Mountains in Central China. The North Qilian Silurian clastic rocks, underlain by the Ordovician back-arc volcano-sedimentary sequences and overlain by the Devonian molasses, are the records of the early Paleozoic tectonic transition from ocean subduction to continent collision in the southern North China Craton. The Youjiang Basin evolved from a passive marginal basin to a foreland basin during the Permian-Triassic time, a sedimentary sequence related to the Indosinian orogny in the SW South China Block. The Jurassic clastic sedimentary rocks in Huangshi Basin south of the Dabie Mountains are the records of the mountain building, and combined with the equivalent sediments in other basins around this mountain, can constrain the exhumation history of the Dabie Orogen. The studied samples are from the North Qilian Lower Silurian, the Youjiang Upper Permian-Middle Triassic and the Huangshi Lower-Middle Jurassic south of Dabie Mountains, including conglomerate sandstone, sandstone, siltstone, and shale. In addition, in Youjiang Basin Triassic volcanics and tuffs were sampled as well. By combing analysis of sandstone detrital modal composition, whole-rock geochemistry, detrital zircon U-Pb ages and heavy mineral chemistry (Cr-spinel and zircon), amounts of provenance-bearing data are obtained.The Qilian Orogen is situated in the northernmost part of the Tibet Plateau, with its formation related to the interaction between North China Craton, Central Qilian Block and Qaidam Block. Constituting the northern part of this orogen, the North Qilian Belt records the collisional assembly of southern North China Craton with Central Qilian Block. The Lower Silurian sediments in North Qilian were mainly sourced from the North Qilian early Paleozoic volcanic arc, the Proterozoic basement of the Central Qilian Block and the Archean basement and its recycled materials of the North China Craton. The lower Lower Silurian in the western segment and the upper Upper Ordovician-lower Lower Silurian in the eastern segment contain detritus from both the early Paleozoic arc volcanics and the continental basement rocks of the Central Qilian Block and the North China Craton. In contrast, continental basements are the main detrital supplier to the upper Lower Silurian sediments with the arc-derived component insignificant. Detrital spinels are observed in the western Lower Silurian sandstones, and have chemical composition similar to that of those from SSZ (supra-subduction zone) type ophiolites, suggesting that the North Qilian oceanic crust has been obducted and eroded. Detrital zircons of early Paleozoic ages are overall comparable to those of continental crust in geochemistry, with a small group of them plotted in the overlapping filed between the continental crust and oceanic crust zircons on the zircon trace element discriminating diagrams. The latter may be derived from a similar ophiolitic source as the detrital spinels. Combined with age data from arc volcanics, arc-related I-type granitic rocks, UP/LT eclogites and blueschists, syn-collisional granitic rocks, post-collisional I-type granitic rocks and continental deep subdction HP/UHP metamorphic rocks, the provenance of the North Qilian Lower Silurian clastic rocks suggests that the tectonic transition in Qilian Orogen from ocean-subduction to continental collision occurred during the latest Ordovician-earliest Silurian time (～450-440Ma)。The Youjiang Basin located in SW China, with the Emeishan basalt province to the northwest, Yangtze carbonate platform to the north, and Nanhua orogen to the east. This basin is separated from the North Vietnam to the southwest by Babu suture zone. During the late Paleozoic-Early Triassic, the sedimentation in this basin is characteristic of alternating deep-water basinal and shallow-water isolated carbonate platform sequences, controlled by northwest-southeast and northeast-southwest fault systems. As such, the Youjiang Basin can be divided into three NW-trending belts, named Napo, Baise and Hechi-Nandan-Ziyun sub-basins in a south to north order. The Late Permian-Middle Triassic strata are composed mainly of clastic turbidites, cherts, mudstones, marls, calcarenites and breccias. The Late Permian sediments have similar geochemical characteristics to the Emeishan high-Ti basalts, the sandstones contain plenty of basaltic rocks fragments, the zircons yield U-Pb ages are consistent with the main eruption stage of the Emeishan Large Igneous rocks and are characteristic of geochemical affinity to those from within-plate/anorogenic rocks, suggesting that Emeishan high-Ti basalts are the major source component and these rocks deposited in the passive margin of SW South China Block. This provenance interpretation is supported by the Late Permian stratigraphic correlation and paleo-current data, and such detrital flux may continue into the early stage of the Early Triassic as indicated by the sedimentary geochemistry. The provenance of the late Early Triassic sediments, however, are changed totally, as suggested by that the sediments have distinctly different geochemistry from the Late Permian-early Early Triassic clastic rocks and volcanic-arc sourced detrital zircons with Permian ages are present in the calcarenites. The geochemistry and zircon U-Pb ages and trace elements of the tuff rocks near the P/T boundary suggest that the magmatic arc is approaching to the South China Carton due to the southwestward seduction of the Jinshanjiang-Ailaoshan-Babu Paleo-Tethyan Ocean, while the Early-Middle Triassic tuffs and volcanics correspond with the subsequent collision. In the Middle Triassic, Youjiang Basin was flooded by turbidity detritus from the surrounding orogens. Therefore, conversion of Youjiang Basin from a passive marginal basin to a foreland basin occurred during the Early Triassic (～250-245Ma).The Lower-Middle Jurassic in Huangshi south of Dabie Mountains is a reverie sequence of recycled sandstone, siltstone and mudstone, including channel, point-bar and floodplain sedimentation in a meandering river for the Early Jurassic Wuchang Formation and channel and inter-channel sedimentation in a braided river for the Middle Jurassic Huajiahu Formation. Paleocurrent and sandstone provenance data suggest that a truck river flowed westward carrying detritus from the South China Block Paleoproterozoic basement and southward tributaries drained the Dabei orogen, with the latter getting stronger in the Middle Jurassic time. Detrital zircon U-Pb ages, CL images and REE elements suggest that one granulite-facies metamorphic zircon with latest Ordovician age is present in the Early Jurassic sandstone, while the Middle Jurassic sandstone contain not only the Ordovician metamorphic detrital zircons but also Carboniferous eclogite-facies metamorphic zircon and Triassic detrital zircons of metamorphic origin, which overlapping in age with the Triassic HP/UHP metamorphism in Dabie Orogen. This result suggests that in this source area occurred corresponding high-grade metamorphism, and such metamorphic terranes have been exhumed to the surface and eroded. Comparison with similar provenance studies from the northern Hefei Basin and eastern Qianshan Basin constrains a differential exhumation style by which the HP/UHP rocks were exposed earlier in the northern part and relatively latter in the southern part. In addition, the Early-Middle Jurassic sandstones in Huangshi Basin and Qianshan Basin yield a similar detrital zircon U-Pb spectrum, which can be correlated with those from the time-equivalent clastic rocks in southern Korea Peninsula and SW Japan, which occur in a comparable tectonic position (situated south of a HP/UHP belt). This data compilation leads supports for hypothesizing an elongated foreland basin south of the Dabie-Sulu collisional belt in China and its eastern extension in Korean and Japan.The Lower Silurian clastic sequence in North Qilian is a sedimentary record related to the early Paleozoic tectonic transformation from active continental margin of the North China Craton to a foreland basin, and the Late Permian-Middle Triassic clastic rocks in Youjiang Basin mark a basin conversion from a passive marginal basin in the SW South China Block to a foreland basin. The initial collisional sedimentary records in North Qilian Lower Silurian sediments include:(1) both the Central Qilian Block and North China Craton providing respective basement materials at this time; and (2) occurrence of orogen-derived detritus, such as detrital Cr-spinels and sandstones with high-Cr contents which argument for an ophiolitic provenance component. In Youjiang Basin, the evidences for initial collision include:(1) Permian volcanic-arc derived detrital zircons in the late Early-Middle Triassic clastic rocks which overlying the passive margin sequences; and (2) Carboniferous detrital zircon of eclogite-facies metamorphic origin occurred in the Middle Triassic sandstones, denoting the quick exhumation of the deep-subducted materials during the collision. The differences in the detrital record of initial collision from North Qilian and Youjiang examples, which have different pre-foreland basin tectonic positions, indicate that the formation and evolution of foreland basin is complicated and related to the tectonic background.Huangshi Lower-Middle Jurassic sedimentary record is a good indicator for the exhumation of Dabie Mountains. During the uplift of the Dabie Mountains, HP/UHP and other high-grade metamorphic rocks were exhumed to surface and recorded as detrital zircons in the Jurassic strata in Huangshi Basin, such as the occurrence of latest Ordovician aged detrital zircon of granulite-facies metamorphic origin in the Lower Jurassic sandstone representing that the early Paleozoic metamorphic terranes have been exhumed to surface by the Early Jurassic or earlier; the occurrence of Carboniferous and Triassic aged detrital zircons of eclogite-or high-grade metamorphic origins in the Middle Jurassic sandstone suggesting that corresponding HP/UHP rocks have been exhumed and exposed to the surface in this time. A significant superiority with implication of detrital record for mountain building is that these special detritus are preserved within a certain stratigraphic sequence, imposing a relative or absolute temporal feature on the orogen exhumation process. More importantly, if the sequence can be traced vertically, the corresponding record will be continuous and thus, reflect a dynamic process in a long-time interval. This is the significance of the study on the Huangshi Early-Middle Jurassic sandstones. In addition, provenance data compilation and comparison from the adjacent basins with Huangshi Basin included show a difference in the sedimentary record which reflects the time-space disequilibrium during the Dabie mountain uplift and exhumation.The key to get efficient sedimentary records related to the orogenic process is to obtain accurate and reliable provenance data, which depends on provenance analysis methods with high-resolution. The composition of clastic sedimentary rocks is the combined function of nature of provenance, chemical weathering, sedimentary sorting and recycling, post-depositional diagenesis and possible metamorphism, and not related directly to the tectonic setting. Considering this, the low success rate of routinely used tectonic discrimination diagrams reflects not only the intrinsic flaw of these diagrams, but also the complexity of sediment generation. If excluding the effects from diagenesis and metamorphism, sediments will be controlled compositionally by source components and sedimentary process. Based on the data of this dissertation, the limitation of the conventional whole geochemical and routine sandstone modal compositional discriminating diagrams was evaluated. It is concluded that special provenance component (e.g. continental flood basalts) and sedimentary process (chemical weathering, sedimentary sorting and recycling) are the main factors leading the results of such diagrams to be deviate from the actual what it is. Considering the composition of the clastic rocks are directly related to the nature of the source rocks and the intensity of chemical weathering, sedimentary sorting and recycling, it is recommended that these routine diagrams should be used with special cautions. Comparing with sandstones, the companying mudstones are characteristic of high contents in Al2O3and Fe2O3+MgO and high ratios of Al2O3/SiO2,Th/Zr, Ti/Zr,La/Y and Sc/La. The difference can be ascribed to the sedimentary processes including chemical weathering, sedimentary sorting and recycling, by which some particals with low density and small size, such as clay minerals, will concentrate in muddy sediments and other particals with great density and large size, such as zircons and quartz, will be enriched in sandy sediments, a detrital sorting which will differentiate elemental distribution in sediments. Continental flood basalt can disperse voluminous mafic detritus into the adjacent passive continental margin, a kind of sediments totally different from quartzose deposits which are usually interpreted to represent a passive margin setting.Contrastingly, single mineral provenance analysis provides more detailed and valuable results. Among them, detrital zircon U-Pb geochronology now becomes a frequently-used method to infer the potential sources. However, its chemical significance to provenance is still under debate. In this dissertation, zircon REE pattern and other trace elements were used to discuss its origin (magmatic or metamorphism), metamorphic condition (if of metamorphic origin) and the nature and tectonics of related magmatism (if of magmatic origin), indicating that zircon chemistry could not be overlooked when studying detrital zircon provenance. To be noted is the designed diagrams using zircon trace elements to separate magmatic zircons from arc-related/orogenic setting from those from within-plate/anorogenic setting, which may be useful in future studies.
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