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Paleopedology and magnetic properties of Sari loess-paleosol sequence in Caspian lowland, northern Iran 被引量:1
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作者 Hamed NAJAF Alireza KARIMI +3 位作者 Gholam Hosain HAGHNIA Farhad KHORMALI Shamsollah AYOUBI Hossein TAZIKEH 《Journal of Mountain Science》 SCIE CSCD 2019年第7期1559-1570,共12页
The objective of this study was to characterize the morphological and magnetic properties of Sari loess-paleosol section in northern Iran for paleopedologic and paleoenvironmental interpretation.The section consisted ... The objective of this study was to characterize the morphological and magnetic properties of Sari loess-paleosol section in northern Iran for paleopedologic and paleoenvironmental interpretation.The section consisted of a modern soil(MS)and three paleosols(PS1,PS2,PS3)separated by loess layers(LS1,LS2 and LS3).Based on particle size distribution,clay mineralogy,carbonates distribution and size of secondary carbonates,pedogenic development of the soils was in order of PS3>PS2>PS1=MS.Presence of redoximorphic features in PS3 was attributed to alternate stagnic saturation due to local water or high precipitation.Dominance of smectite and vermiculite as well as large carbonated dolls in PS3 indicated suitable environment and sufficient time for pedogenic development.Magnetic properties(χlf andχfd%)were distinctly higher in MS,PS1 and PS2 when compared to loess layers.The Lowest magnetic properties values were observed in PS3 which can be the result of ferrimagnetic minerals destruction under hydromorphic conditions.The highest Fed content occurred in PS3,however,lowχlf/Fed ratio indicated that majority of the iron minerals in PS3 are not magnetic.In conclusion,the particle size distribution,clay mineralogy and carbonates features were indicative of pedogenesis intensity,whereas,magnetic properties were useful to characterize the pedogenic environment. 展开更多
关键词 iranian loess plateau MAGNETIC susceptibility Climate change PALEOPEDOLOGY
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伊朗黄土高原表土磁性特征与古气候指示意义 被引量:4
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作者 魏海涛 陈发虎 《第四纪研究》 CAS CSCD 北大核心 2022年第1期261-271,共11页
全球变化研究中的现代过程研究越来越成为定量重建工作的先决前提,而由于如黄土等气候记录载体沉积分布的全球性与沉积环境的多样性,更需要就具体的研究区进行有针对性的现代过程工作以最大程度地保证重建工作的可靠性。西起地中海、东... 全球变化研究中的现代过程研究越来越成为定量重建工作的先决前提,而由于如黄土等气候记录载体沉积分布的全球性与沉积环境的多样性,更需要就具体的研究区进行有针对性的现代过程工作以最大程度地保证重建工作的可靠性。西起地中海、东至帕米尔的广大区域是丝路文明演化的关键地区,其过去气候变化也是了解北半球中纬度气候演化与机制的重要拼图。本研究即采集位于该区之里海东南缘的伊朗黄土沉积区域的现代表土,并联系气候要素考察其磁性特征的空间变化。结果显示主要分布于冬春季节的年均降水其变化控制了亚铁磁性矿物的空间分异,包括次生超细颗粒含量变化与磁赤铁矿化程度,典型的磁学参数如百分频率磁化率值的变化可以定量记录年均降水值的变化。结合相关关系函数,可以为该区过去降水变化的定量重建提供准备并为进一步理解区域气候系统演化与机制提供支持。 展开更多
关键词 伊朗黄土高原 丝绸之路核心区 百分频率磁化率 定量重建 表土现代过程 地中海气候
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