Study On Change Of Paleoclimatic Environment Of Late Pleistocene In Huaihe Source Area

This article chooses that the research region is located between the boundaries of Henan Province northern the Tongbo Mountain and Dabie Mountain the foothill area Huaihe River source area. It is situated at the area south of Yellow River center, located the Chinese north and south ecology, in the climate divided line belt, north Dabie Mountain foothill quaternary period deposit distribution widespread, the section plane is continual, appearing good and studying the quaternary period and even now Dabie Mountain prosperously rises, the Huaihe River basin subsidence and the new tectonic movement and the environmental trend and the scientific question good place.Since through to Dabie Mountain north the foothill quaternary period soil deposit research, has analyzed the quaternary period this local environmental variation and Huaihe River's formation; Has studied the eastern part ecological environment question in China, to the time forecast the future ecological environment the change tendency will provide the basis. Through to the Guang mountain section plane loess size test and the chemical element analysis, it obtains this local Guang mountain section plane loess the origin, namely loess environment of deposition as well as climate change.Below this research mainly draws the conclusion:First, the Guang mountain loess size composition take the thick silt (10～50μm) primarily, the content as 40%, but > 50μm content equally reaches 30.29%, on the one hand the thick silt is very important speaking of the travel fatigue loess. Because it is the travel fatigue "Basic Grain size" , its content is the travel fatigue loess distinguishes one of between other deposit important symbols, is called " Basic Grain size ". On the other hand, only has the hydrodynamic force to carry on it which the minute elects; 50μm pellet, its content is also bigger. The explanation already has the wind regarding the light mountain section plane loess environment of deposition to become the origin also to have the aqueous origin, and the different time, two kind of origins functions are different.Second, the light mountain section plane late Pleistocene loess and the loess plateau loess matter has the approximate element geochemistry characteristic, its main chemical composition basic consistent, the average chemical composition and the earth's crust average chemical composition is similar, Fe₂O₃, SiO₂ and Al₂O₃ three content reaches above 86%. This kind of remarkable rich hard silicon aluminum phenomenon has prominently indicated this area mainly by the hot and damp primarily climate characteristic. The oxide compound had reflected since the light mountain section plane late Pleistocene mainly by the hot and damp primarily climate, the relative eluviates strongly and the oxidation has been stronger.Third, Guang mountain section plane Fe³⁺/Fe²⁺ change curve and entire iron determine content curve shape similar, change synchronization, tendency consistent, is being obviously connected, but assumes the counter-correlational dependence with Si,Al,Fe rate the curve. It had reflected since the climate will have been sooner or later changed overall that the temperature is low in the late Pleistocene. The Intermediate stage temperature higher that is quite frequent in the intermediate stage climate undulation.Above the synthesis we may obtain this local loess the open country characteristic, the regional character and it's the land form department classify the various aspects to demonstrate that it constituted the light mountain section plane loess matter to originate disagreeing the loess plateau typical loess origin similar, also not and the rivers deposit origin was same. Constituted this local unique environment origin. The climate characteristic is developing the hot and damp to dry and cold direction.