The Study On Change Of Palaeo Environment In Minle Aera Of Gansu Province Since The Late Pleistocene

Minle area, ranking in the north of Qilian Mountain, located in the middle of Hexi Corridor, is a climate-sensitive area. Therefore the sampling loess section of the study area, revealing the area Quaternary climatic characteristics and predict future environmental changes have a certain significance.Thesis was on Elm Hill active fault 1: 50,000 active fault mapping project based on the completion of this study Binggoutai and Dongjiazhuang sectional Minle areas were measured, sampled, and the magnetic susceptibility and particle size analysis,restored Study of late Pleistocene last climate change and the evolution of the history of interglacial since. The following conclusions:1, Binggoutai station sectional size and magnetic susceptibility data and cross-sectional view taken Dong village is reasonable, showing under dry and cold weather conditions, strong winter wind, sediment grain size generally larger, poorly sorted, corresponding to a lower susceptibility. Under warm and humid climate and background, winter monsoon is weak, sediment grain size is small, the corresponding magnetic susceptibility show also higher. And two cross-sectional deposits belong aeolian deposits.2, The study area since the late Pleistocene environment experienced about five stages of change, since ancient times were(.122.10 kaB.P.-91.36 kaB.P) warmer Late Pleistocene interglacial;(Cold late Pleistocene glacial to interglacial advanced to the last ice age that is 91.36 kaB.P to 70.23 kaB.P early part of the environmental characteristics of sedimentary strata extremely objective reasons failed to get);...colder late Pleistocene early last glaciation(70.23 kaB.P.-55.99 kaB.P);. warmer mid-late Pleistocene last glacial Period(about 55.99 kaB.P.-23.60 kaB.P);. the most cold, dry late Pleistocene glacial late last glacial Maximum( about23.60 kaB.P.-13.78 kaB.P);. the most warm and humid Holocene(13.78 kaB.P so far).3, The oxygen isotope curve Binggou station sectional and sectional Dong Villageand Ancient Ice Core recorded were compared and found the existence of a good relationship, in turn correspond to ancient times: Dong village sectional corresponding to Guliya ice core oxygen isotope section 5(a, b, c, d, e) stage;Binggou station corresponding to the first sectional 4,3,2,1 stage. And some peak trough various stages within also corresponds well, especially some cool events and warm events during the late Pleistocene glaciation and a new period of the world, and the Guliya ice core oxygen isotope marine oxygen isotope curve reflected the well-being events had a very good response, and further demonstrates the Gansu Corridor region and the climate sensitivity folk areas. Rapid cooling events in10.22 kaB.P. Place presumably in response to the Younger Dryas event.Rapid waiming events in 12 kaB.P. Place presumably in response to the Bolling event.