Ding R.-X.,Sun Yat Sen University |
Ding R.-X.,Guangdong Province Key Laboratory of Geological Process and Mineral Resource Investigation |
Chen G.-N.,Sun Yat Sen University |
Chen G.-N.,Guangdong Province Key Laboratory of Geological Process and Mineral Resource Investigation |
And 2 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2012
The paleoelevation reconstruction of an orogen is of great significance to the study of mountain building and of paleoclimate. The authors use the thermal history data of low-temperature thermochronology to reconstruct the paleoelevation of the Dabie orogen since Late Cretaceous. The reconstruction procedure includes (in order) the following: digitalizing the low-temperature thermal history modelling curve of the Dabie orogen, extracting the time-temperature data, calculating the average exhumation thickness of the focused region by the spatial interpolation method, the deflection isostatic correction, the calculation of the average paleoelevation change, and the two-dimensional integral calculation to get the amplitude decrease of paleotogography. The result shows that the average exhumation thickness of the Dabie orogen since 90 Ma is about 5.44 km, and the average elevation decrease of paleotogography is 2.86-4.16 km, the upper limit of the amplitude decrease of paleotogography is 4.49-6.53 km.
Lou F.,Sun Yat Sen University |
Lou F.,Guangdong Province Key Laboratory of Geological Process and Mineral Resource Investigation |
Chen G.-N.,Sun Yat Sen University |
Chen G.-H.,Sun Yat Sen University |
Huang H.-H.,Sun Yat Sen University
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2013
With comparison of the fluorescence spectroscopy and plasma-mass spectroscopy analysis results of the Meso/Cenozoic basic rocks of SE China, the authors found that the average SiO2 content of the Mesozoic basic rocks in this area is about 50%, while that of the Cenozoic basic rocks is about 43%. The former belongs to the basic group and the later to the ultrabasic group in igneous rock classification. Cenozoic basalts, accompanied with high magnesium content and low silica-alumina component, are obviously basic or ultrabasic rocks. Distinctive difference in the content of trace elements and of REE is also presented between the Mesozoic and the Cenozoic basic rocks. Distribution models of both trace elements and REE of the Mesozoic basic rocks are similar to those of the upper crust, and the models of the Cenozoic basic rocks are like those of OIB, indicating that basic rocks of the Cenozoic and OIB should originate from the mantle while that of the Mesozoic is from the bottom part of the upper crust with relationship to the evolution of the Mesozoic crustal magma layer of this area.
Peng Z.,Sun Yat Sen University |
Peng Z.,Guangdong Province Key Laboratory of Geological Process and Mineral Resource Investigation |
Chen G.,Sun Yat Sen University |
Chen G.,Guangdong Province Key Laboratory of Geological Process and Mineral Resource Investigation |
And 5 more authors.
Geotectonica et Metallogenia | Year: 2015
Granite-type uranium deposits commonly formed in the latest stage of platform-reactivation period, which were products of multiple crustal melting (or remelting). Studies of hydrothermal alteration and related uranium mineralization indicate that U-bearing fluid was derived from magma system characterized by multiphase melting (or remelting); and the ore fluid was sulfur-deficient and vapor-rich. With decreasing temperature during the ascent of the U-bearing hydrothermal fluid, precipitation of minerals follows the order of oxides-fluorides-carbonates-hydrates. Deposition of pitchblende starts in the late oxide-stage and ends in the carbonates stage. The ore-vein types vary in the order of high temperature barren zone-large vein zone-veinlet zone-anilox zone-low temperature barren zone from the depth upwards. Combining the zoning characteristics and the geological, geochemical and geophysical data, we propose a prediction scenario for the concealed ore-bodies in the No.XXX deposit, the Xiazhuang ore-field. ©, 2015, Science Press. All right reserved.