【摘 要】
：
There exist five primary periods of 2 930, 1 140, 490, 250 and 220 a in the Holocene climatic variations in the Huguangyan Maar Lake, according to the energy-sp
【机 构】
：
LIU Jiaqi,GeoForschungsZentrum Potsdam D-14473 Potsdam
论文部分内容阅读
There exist five primary periods of 2 930, 1 140, 490, 250 and 220 a in the Holocene climatic variations in the Huguangyan Maar Lake, according to the energy-spectrum and filter analyses of high-resolution time sequences (10-15 a) of the sediment dry density. The peak values of the three temperature-decreasing periods with the 2 930 a cycle occur at about 7 300, 4 250 and 1 200 Cal. aBP. There are 7-8 temperature-decreasing periods with the 1 140 a cycle, and the climate fluctuation range is largest in the early Holocene, and reduces gradually in the middle and late Holocene. The millennial-scale climatic change in the Holocene may adjust the global water cycle and the thermohaline circulation intensity through the harmonic tones of the earth's precession cycle, which in turn influences the global climate change.
其他文献
新太古代-古元古代过渡时期变质杂岩构造演变的运动学和动力学过程是地球科学核心问题之一。针对吉林古陆边缘变质杂岩成因归属方面的争议,以吉林板石沟地区为例,在新太古代-古元古代过渡时限内(2600～2000Ma),从早到晚、从古陆中心到边缘,初步查明古板块动力体制发生一系列变化,即古板块板底垫托、水平推移、俯冲、板内伸展和拆离构造;对应控制地壳运动方式共有5种:古陆垂直运动、古陆水平运动、古陆拉张与接
首先分析了GPS PDA技术应用于土地变更调查的意义 ,研究了单基准站后处理差分解算、坐标转换模型。最后以一实测结果表明了该技术的可行性和有效性。
通过研究陕南早寒武世疑难化石Rhombocorniculum cancellatum,首次发现其骨片主要由左型和右型两类刺体组成,两类刺体在样品中数量相近,指示它们为某类两侧对称的动物所有.研
根据采自青海南部高原曲麻莱、治多地区树木年轮样本,建立了该地区高原树木年轮年表序列通过响应函数计算得出,该年表对高原春季(4～6月)的气温和降水量反映敏感,定义了湿润指
Granitic gneiss on Duku highway in western Tianshan has been dated by the U-Pb zircon method. When plotted on the concordia diagram, the results give linear dat
网络安全态势的研究是动态地认识大规模分布式网络安全的信息安全新热点之一。由于大规模网络的复杂性,及对网络整体安全越来越高的要求,常规的安全解决方案不能较好地完成保
本文就提高沥青路面压实质量问题,从碾压温度、压实速度与遍数、振频与振幅及沥青混合料压实特性几个方面进行了阐述.
The global tectonic change deduced from geophysical research was first identified by space geodetic data from VLBI, GPS and SLR measurements. Whether using geod
Based on the CTD and meteorological data obtained by R/V Xiangyanghong No.14 in the South China Sea (SCS) in the summer of 1998, both current velocity and volum
UPS的意思是不间断电源,它不仅能够在突然断电情况下起到应急作用,而且可以消除各种电源污染,是一种高质量的电源.本文简单介绍了UPS的一些特点和主要组成部分,重点介绍了UPS