The magnetic properties of Attock loess and its environmental significance in Pakistan
The magnetic properties of Attock loess and its environmental significance in Pakistan
复制标题
巴基斯坦阿托克黄土的磁特性及其环境意义
DOI：
10.1016/j.quaint.2021.11.011
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发表时间：
2021-12
影响因子：
2.2
通讯作者：
Zhou Shengfang
中科院分区：
文献类型：
--
作者：
Lian Yuechen;Liu Xiuming;Ali Rashid Tabrez;Ma Mingming;Mao Xuegang;Qi Xinyao;Zhou Shengfang
黄土-古土壤序列的磁化率是记录古气候的重要指标，不同地区磁化率与气候变化的关系不同。深入分析磁性矿物的组成、含量和演化机制，有助于加深对不同地区磁性信号的认识。通过对巴基斯坦北方白沙瓦盆地Attock（ATT）地区黄土-古土壤序列中环境磁学和地球化学元素的系统研究，探讨了磁化率作为古气候代用指标的意义和局限性，以及磁化率的变化机制。结果表明：1）ATT剖面磁性矿物组成与中国黄土高原相似，但不同矿物的含量差异较大。黄土层含有一定量的磁铁矿和磁赤铁矿，以及少量的针铁矿和赤铁矿。此外，软磁性矿物的含量相对高于古土壤，古土壤中含有磁赤铁矿，几乎不含磁铁矿。ATT剖面成土环境的有效湿度在磁化率润湿临界值F附近波动（B-C区），导致磁化率与气候关系不佳; 3）Rb/Sr、K/Na、淋溶系数、<2 μm颗粒含量与地层相关性较好，可作为该区古气候变化的指示指标。了解B-C区有助于理解磁信号与某些地区气候的复杂关系，更好地解释磁信号所携带的环境信息。
The magnetic susceptibility of the loess-paleosol sequence is considered a significant indicator for recording paleoclimate, and the relationship is different between magnetic susceptibility and climate variation in diverse regions. A deep analysis of the composition, content, and evolution mechanism of magnetic minerals is helpful to enhance our understanding of magnetic signals in different regions. This paper presents a systematic study of environmental magnetism and geochemical elements in the loess-paleosol sequence of the Attock (ATT) area in the Peshawar Basin, northern Pakistan, exploring the significance and limitation of magnetic susceptibility as a proxy index of paleoclimate and the variation mechanism of magnetic susceptibility. The results showed that: 1) the ATT section had a magnetic mineral composition similar to that of the Chinese Loess Plateau; however, the contents of different minerals were distinguishable. The loess layer contained a specific amount of magnetite and maghemite and a handful of goethite and hematite. Additionally, the content of soft magnetic minerals was relatively higher than that of paleosol; the paleosol contained maghemite and nearly no magnetite. Furthermore, it contained more hematite and goethite, and the hard magnetic and paramagnetic minerals were dominant; 2) the effective humidity of the pedogenic environment in the ATT section fluctuated around the magnetic susceptibility wetting critical value F (B–C region), resulting in a poor relationship between magnetic susceptibility and climate; 3) Rb/Sr, K/Na, the coefficient of eluviation, and the content of <2 μm particles were well correlated with the stratum and can be used as paleoclimatic variation indicators in this area. Understanding the B–C region is helpful to comprehend the complex relationship between magnetic signals and climate in some areas and better interpret the environmental information carried by magnetic signals.
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影响因子：
64.8
作者：
L. Zhou;F. Oldfield;A. Wintle;S. Robinson;J. T. Wang
通讯作者：
L. Zhou;F. Oldfield;A. Wintle;S. Robinson;J. T. Wang
DOI：
10.1016/s1386-1425(01)00445-0
发表时间：
2001-11
期刊：
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
影响因子：
--
作者：
H. Ruan;R. Frost;J. Kloprogge
通讯作者：
H. Ruan;R. Frost;J. Kloprogge
影响因子：
3.9
作者：
Cong-Qiang Liu;A. Masuda;A. Okada;S. Yabuki;J. Zhang;Z. Fan
通讯作者：
Cong-Qiang Liu;A. Masuda;A. Okada;S. Yabuki;J. Zhang;Z. Fan
影响因子：
3.5
作者：
H. Nesbitt;G. M. Young
通讯作者：
H. Nesbitt;G. M. Young
影响因子：
64.8
作者：
J. Beget;D. Hawkins
通讯作者：
J. Beget;D. Hawkins