Denudation as unique Earth Crust sampling procedure: additive effect of sedimentary differentiation and homogenization
S. Shnyukov, E. Tegkaev, I. Lazareva, O. Andrieiev and A. Aleksieienko
Event name: 18th International Conference on Geoinformatics - Theoretical and Applied Aspects
Session: Geological Modeling
Publication date: 15 May 2019
Info: Extended abstract, PDF ( 509.59Kb )
Price: € 20
Large geochemical data set, obtained for Precambrian Ukrainian Shield (USh) rock associations, modern sediments and Phanerozoic sedimentary rocks from basins of USh periphery (accumulation reservoirs of eroded upper crustal material) yielded following results: (1) SiO2, Zr and LREE in rocks associations of USh are characterized by complex distribution, which contradicts modern evaluations of lower, middle and upper continental crust. (2) Distribution of SiO2, Zr and LREE in modern sediments and Phanerozoic sedimentary rocks is caused by two factors - sedimentary differentiation and sedimentary homogenization. Second factor erects a set of contrast maximums, which reflect composition of upper continental crust. Results obtained point out that research of zircon and monazite large detrital populations from river sands and sedimentary rocks require consideration of homogenization and differentiation effects. In order to take them into account, it is vital to develop specialized criteria, which can be based on a principle maximum conformity of Zr and LREE concentrations in the sampled sediments and sedimentary rocks to evaluated concentrations in upper continental crust. Implementation of such criteria would significantly enhance reliability of further constraints of the continental crust evolution based on age determinations and trace element geochemical data for zircon and monazite large detrital populations.