Quaternary’s Micropalaeontology And Climate Of The Lower-liaohe Plain

Based on petrographic analysis,paleomagnetic analysis,biological analysis,strataanalysis,The Pleistocene of the lower-Liaohe Plain contains Qp1t,Qp2z,Qp3y.The Holocenecontains Qh1p, Qh2d, Qh3z.The distribution of the Quaternary strata is affected by terrain,tectonic movement, erosion-transport-deposition of external forces.The quaternary of thecoastal plain is the thickest,the Central Plain is also thick, The sloping plain of westernpiedmont and the sloping plain of eastern piedmont is the thinnest.The Central Plain andCoastal Plain is formed by alluvial.The sloping plain of western piedmont and the slopingplain of eastern piedmont is made of alluvial fan.Climate changed significantly during theQuaternary,the climatic cycles of glacial-interglacial appeared alternately,which determinedthe elevation of sea level.The sea had its transgression during glacial,the sea had its regressionduring interglacial.The change of sea-level in the Quaternary helps recall paleoclimate.Thelower-Liaohe Plain experienced three large-scale transgression since the middle ofPleistocene.This was directly controlled by the glacial-interglacial cycles.Pollen analysis isone of the important methods to recall the ancient climate.This method has become one of themost important direction of pollen research.The pollen of The lower-Liaohe Plain located inthe "big north area".Shrub steppe, deciduous broad-leaved forest, coniferous forest were oncelocated in the lower-Liaohe Plain during the Quaternary.The species composition ofvegetation was highly affected by the ancient climate.The Quaternary stratum of helower-Liaohe Plain is very thick.There is a lot of pollen in the stratum.Finding out theadvantage combination from these pollen assemblage can help analyze the ancientprecipitation and the temperature. The Pleistocene has nine advantage combination.The nineadvantages combination was corresponding with the nine stratum.The Holocene includedthree advantage combination,we can analyze the change of the paleoclimate according thetwelve advantage combination. We will find out how the paleoclimate affected the vegetationdistribution and vegetation migration.The paleoclimate of Quaternary is a important part ofthe study in environmental changes,and the micropalaeontology contains the changeinformation, grasping the micropalaeontology of the every stratum during Quaternary isvery importang,which will show the paleoenvironmental information of the Lower-LiaohePlain.