Geochemical Characteristics And Grain Size Analysis Of Loess Of Changxingdao

Loess is a typical Quaternary sediment.The universality,continuity and sensitivity of loess distribution can well explain the evolution information of Quaternary paleo sedimentary environment.In this paper,the loess section of Hejiaquan on Changxingdao,Dalian is taken as the research object.Through the qualitative description and quantitative analysis of the geochemical and granularity characteristics of the loess section,the climatic evolution and provenance information of the loess sedimentary environment in this section are discussed.Chemical elements measurement of Loess by using ZSX Prinmus II X ray fluorescence spectrometer of Japanese science Rigaku company.The main element oxides in Hejiaquan loess section of Changxingdao are SiO₂ and Al₂O₃,the average content of which is 78.2%,the average content of other oxides is K₂O?2.90%?>Fe₂O₃?2.75%?>CaO?2.74%?>Na₂O?1.37%?>MgO?0.86%?>TiO₂?0.45%?.The variation coefficient of CaO was the largest,in which the climate fluctuation was the most obvious from 270cm to 120cm,and the content of CaO increased from 3.12%to 5.33%.The average CIA of loess in Hejiaquan is 61.23,which is smaller than that in Luochuan loess?63.73?,in Zhenjiang Xiashu loess?70.45?,in Qidingshan loess?69.82?and in Zhoujiagou loess?66.19?,which is similar to that in Tuojidao?61.43?.The grain size of loess is tested by the LS13 320 laser diffraction particle grain size analyzer produced by the American Beckman Kurt limited company.Fine sand group Hejiaquan loess section size distribution in the 4?²?peak with the content of 37.1%of the total,coarse sand peak group distributed in 6?⁵?with 34.40%of the total content.The Loess average is 4.41 with average diameter,average standard deviation was 1.92,the average value of skewness was 0.81,ranged from 0.44 to 1.39,from positive to negative bias bias near,kurtosis average value is 3.61,which belongs to the narrow peaks,silt clay ratio?K_d?with an average of 6.81,the overall K_d large.The chemical elements of a comprehensive analysis of Changxingdao loess section Hejiaquan and grain size characteristics,the Hejiaquan loess section has lower CIA value and higher K_d value,weak weathering,weathering and belongs to the preliminary stage,the top Qingdingshan loess and Zhoujiagou loess section comparison,showing the degree of weathering of loess in Liaodong peninsula from South to north with a decreasing trend.The grain size is mainly fine sand,and the coarse silt is second,which shows the grain size characteristics of the Aeolian Loess.The overall grain size is coarser,reflecting the dual source characteristics of low altitude near source concentrated dust fall?near shore source deposits?and continuous high altitude transportation dust fall?northwest inland wind dust deposition?.The sedimentary environment of the Loess climate from warm and humid to cold.