【摘 要】
:
Palaeohydrological investigations were carried out in the middle Beiluohe River valley in the middle Yellow River basin.Palaeoflood slackwater deposits (SWD
【机 构】
:
Department of Geography, Shaanxi Normal University
论文部分内容阅读
Palaeohydrological investigations were carried out in the middle Beiluohe River valley in the middle Yellow River basin.Palaeoflood slackwater deposits (SWDs) are natural records of overbank flooding and are often identified in the Holocene aeolian loess-soil profiles along the river valley.Three bedsets of palaeoflood SWDs were found within the mid-Holocene Climatic Optimum palaeosol (S0) on the right riverbank.Both the sedimentary and the analytical results, including magnetic susceptibility, grain size distribution, and concentrations of chemical elements, indicate that these palaeoflood SWDs were deposited from the suspended sediment load of overbank flooding.
其他文献
距今约400 ka的中更新世间冰期(MIS11)经历了与全新世(MIS1)近乎同步的太阳辐射变化,在能获得古气候记录的时段中,最为适合与全新世进行对比研究.本文以湖北永兴洞石笋为研
珠江三角洲全新世腐木泥炭堆积层的分布与地形和河流演变关系密切。本文研究取自81个钻孔和剖面的数据,将其中21个含有腐木描述的钻孔或者剖面与地形图的高程与河流位置进
在第四纪地质发展史中,晚更新世与全新世之间的过渡时期及其后所发生的环境和气候变化,对现代人类生存环境的影响非常深刻。我国北方晚更新世以来古环境变化在总趋势上一致
The T-gate stem height of InAlAs/InGaAs InP-based high electron mobility transistor (HEMT) is increased from 165 nm to 250 nm. The influences of increasing the
小冰期的起止时间及温湿配置可能存在较大的区域差异性,但目前东南部季风区高分辨率记录研究比较缺乏,限制了对此阶段气候与环境变化重建及内在机制的深入认识。本研究对赣
进入21世纪,全球范围内面临着一系列的环境问题,人类社会再也无法回避人地关系的突出矛盾。为了预测未来全球变化趋势,必须了解过去全球变化规律,尤其是人类文明大发展的全新
火是陆地生态系统中一个重要的扰动因子。正确理解火、气候变化、人类活动以及植被组成之间的关系对当今及未来(全球变暖背景下)景观设计与管理都有重要意义。而地层中保
为了便于领导,便于促进生产的发展,经河北省人民委员会第二十次会议通过,并报请国务院批准,决定将原唐山专区所属汉沽市均行政区域划归天津市,同
In order to facilitate l
We study some nonlinear waves in a viscous plasma which is confined in a finite cylinder.By averaging the physical quantities on the radial direction in some ca
古温度的定量重建一直是古气候研究领域的重点和难点,但是其对于理解气候变化机制具有重要意义。同时,研究青藏高原温度变化幅度对于理解高原对全球气候系统变化的响应极其