【摘要】 由于特殊的地理环境,泥石流沉积成为晚更新世小江流域主要的沉积类型[1].本文对小江流域东川蒋家沟泥得坪台地晚更新世泥石流沉积剖面进行了孢粉研究,发现剖面沉积环境中的花粉组合主要以木本为主,其中以草本含量为主的样品,也是以喜湿的花粉类型为主,反映了泥石流爆发时期气候温暖潮湿的特点.在植被茂密降雨量丰富的地区发生高频率的泥石流,主要原因是该区处在构造活动强烈的地震带,有丰富的碎屑物质,所处地形陡峭,为泥得坪台地泥石流的爆发提供了外应力条件.更多还原

【Abstract】 Because of the special geography environment,debris flow aggradation becomes the main sediment type of XiaoJiangRiver in late Pleistocene[1].This article studied the deposit pillar of late Pleistocene NiDePing mesa in JiangJia valley besides XiaoJiang River in DongChuan,it shows that there is a high quantity of plant pollen in the sample of deposit pillar,even in the sample of which is in high quantity of grass,the main is hygrophilous pollen,it reflects that it was warm and wed climate during the eruption of debris flow.However,debris flow occured in a high frequency during the area of a dense forest and large rainfall,because it located in the earthquake area of intense tectonic activities.There were so many oddments and the landform is cliffy,it provided outside force to the debris flow of NiDePing mesa.更多还原