Provenance Tracking Of River Sediments In The Fenshui Watershed-a Typical Branch Of Qiantang River Basin, Zhejiang Province, China

On the basis of "Research on the 1.4nm clay minerals in river sediments and the tracing method within the Qiantang River Basin", this article is mainly discussing the provenances of Fenshuijiang basin ---a typical branch of Qiantang River, this project focuses on the in-depth study of the clay minerals and environmental magnetic as potential tracers. Through comparing river sediments to top soil from the aspect of clay minerals and magnetic properties, we conclude the provenances of river sediments and its soil characteristics. And on this basis, the paper further analysis the processes of soil forming and which lead to differences in the content of clay minerals reasons. Primary conclusions are as follows:1) Magnetic minerals from different river stretch are almost ferrimagnetic mineral, which dominates the magnetic characteristics of the samples. The magnetic parameters (xlf/xfd%/HIRM/S-300mT) have the same variation range and medium value, at the same time there is a certain amount of super paramagnetic material contribution to the magnetic susceptibility. The ferrimagnetic mineral have thicker crystals in the Changhua River than that in the Tianmu River, both of the full river are almost from pseudo-single to multi domain.2) Fuchun river sediments χlf, χfd%/, S-300mT Jiang Duan relatively close, such as magnetic parameters and water show that magnetic mineral sediments dominated by ferrous magnetic minerals, there are a few super paramagnetic material, ferrous magnetic mineral grains with false effect (PSD)-multiple domain (MD); Jiang Duan has higher HIRM, but relative to the water xARM, that contains more incomplete fuchunjiang antiferromagnetic minerals and the ferrous magnetic mineral effect; The magnetic parameters of water into the river after the river, fuchunjiang χlf, SIRM, HIRM, S-300mT, χARM/χ value increased, shows that the water river sediment into improving fuchun river sediment magnetic mineral content, but the contribution value is limited.3) The soil from the different types is obvious. Soil originated from granite rocks and Acidic igneous rocks has higher χlf/SIRM/HIRM and lower χfd%/χ χARM/χ /xARM/SIRM, This shows that the content of ferrimagnetic mineral and the incomplete antiferromagnetic minerals in topsoil are higher, but ferrimagnetic mineral dominate the magnetic characteristics of the samples, magnetic mineral particles in general is very thick, are almost multi domain, and has less super paramagnetic material. The soil from the different types of sedimentary rocks magnetic parameters are different, but is obviously difference with igneous rock (granite), has higher χfd%/χARM/χ/χARM/SIRM and lower χlf/SIRM, Overall displays the ferrous sedimentary rock magnetic mineral content is low, pseudo single domain to multi domain in size, dominates the magnetic properties of the topsoil. Fenshuijiang river basin on the whole is given priority to with sediment, igneous rock (granite) proportion is very small, Sedimentary rocks on the development of the soil all the magnetic parameters and river sediments corresponding to better reflect the sediment from the "source" to "sink" source conveying process.4) Clay mineral semi-quantitative experimental results show that:the clay mineral in the sample is given priority to with illite, kaolinite, vermiculite, chlorite and smectite in turn,different section of clay mineral content is different, the content of Changhuajiang river sediments illite(61.3%), kaolinite(16.6%), vermiculite(10.9%), chlorite(9.6%), smectite is less; the content of Tianmuxi river sediments illite(68.9%), kaolinite(13.2%), vermiculite(12.3%), chlorite(4.1%), smectite is less; the content of Fenshuijiang river sediments illite(64.4%), kaolinite(16.0%), vermiculite(13.2%), chlorite(5.5%), smectite is less; Fenshuijiang to the clay mineral content in the triangle more clearly reflect the differences of three large section of the river, river sediment of clay mineral content difference is mainly affected by the source area surface soil types.5) The clay mineral combination type by source area parent rock, climate and human activity is a combination of:The same altitude zone (climate) same sedimentary rocks and the development of soil clay minerals in acidic volcanic rock and granite combination difference is obvious, Sedimentary rocks have more illite, acidic volcanic rock and granite has more kaolinite; As the altitude rises in a lithologic (the temperature gradually lower) chlorite content gradually increased,1.4 nm mineral water river dam upstream samples more vermiculite/chlorite exist in the mixed layer mineral, while downstream samples is less, it could water river upstream of the dam block to sand, lead toFenshuijiang river sediment upstream and downstream.