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岩石学报 1995
The Petrology Model of the Geoscience Transection,for the Continental Lithosphere Beneath Luoyang-Yichuan-Shiyan-Zigui,Qinling,China
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Abstract:
In accorolance with p--wave (Vp) model of this cross section and deep--seated source xenoliths data of the basic igneous rocks and kimberlites or granite intrusion on orogenic belts, and in view of that follows: information of crust and mantle deep constiture and evolution from igneous and metamorphic rocks, specially high and ultra-high pressure metamorphic rocks and ultra--basic rocks, and as correlation with experimetal geophysical data of above--mentioned rocks. Besed on the study of above, it is possible to establish the lithosphere petrology model of this cross section.This model of petrology was suggested that the North China craton, the Yangtze craton, the Northern Qinling and the Southern Qinling Orogenic belts and intermediate zone of orogenic belts model of petrology make a great difference. The Northern China craton deep crust is mainly compossed of granulite factes intermediate--acidity gneiss and charnokites with minor basic granulite. Yangtze craton deep crust is mainly compossed of the hornblende--granulite facies acidity gneiss and TTG suites with a large quantity metamorphic basic igneous bedrock. Medium--deep crust on the Northern and Southern Qinling orogenic belts each and every to inherited Northern China craton and Yangtze craton medium--deep crusts characters, it's stongly to be rebuilded at Same time. The upper mantle on the Northern and Southern Qinling orogenic belts are great dlifferent from each other. The Northern Qinling Upper mantle is mainly compossed of eclogiees and horrblende-eclogites, The Southern Qinling is mainly compossed of serpentinized peridotites. All above--mentioned tectonic units deep 100~120km. There is Garnet lherzolite blow the mantle. To sum up, Qinling orogenic belts is that a bulk verious petrological tectonic Unit to make a whole. This bulk is recorded about 30 hundred my Earth evolition history, not a simple model of bed-sphere structure.