Remanence Characteristics of Different Magnetic Grain Size Categories at Xifeng, Central Chinese Loess Plateau

AbstractUtilizing the thermal unblocking of low-temperature remanent magnetization in superparamagnetic (SP) ferrimagnets and the low-temperature demagnetization of multidomain (MD) magnetite remanences, the relative proportions of SP, MD, and singledomain (SD and SD-like) ferrimagnets are estimated in the topmost part of a loess section at Xifeng, China, which covers about the past 130,000 yr. SP ferrimagnets are commonly regarded as pedogenic (authigenic) products while the MD component is believed to have a detrital origin. These measurements, therefore, provide new data which improve our understanding of the characteristics and distribution of the different magnetic grain-size fractions present in loess and soils. In particular, our measurements indicate a larger MD fraction in soil than in loess, a result which indicates that although enhancement of the SP ferrimagnet fraction dominates the increased low-field magnetic susceptibility of paleosols, an enhancement of the MD fraction, probably through leaching, also plays an important role during pedogenesis.

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Asian summer monsoon instability during the past 60,000 years: magnetic susceptibility and pedogenic evidence from the western Chinese Loess Plateau

Earth and Planetary Science Letters ◽

10.1016/s0012-821x(99)00053-9 ◽

1999 ◽

Vol 168 (3-4) ◽

pp. 219-232 ◽

Cited By ~ 130

Author(s):

Xiao-Min Fang ◽

Yugo Ono ◽

Hitoshi Fukusawa ◽

Pan Bao-Tian ◽

Ji-Jun Li ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Loess Plateau ◽

Summer Monsoon ◽

Asian Summer Monsoon ◽

Chinese Loess Plateau ◽

Chinese Loess ◽

The Past ◽

Asian Summer

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Six million years of magnetic grain-size records reveal that temperature and precipitation were decoupled on the Chinese Loess Plateau during ~ 4.5–2.6 Ma

Quaternary Research ◽

10.1016/j.yqres.2013.01.002 ◽

2013 ◽

Vol 79 (3) ◽

pp. 465-470 ◽

Cited By ~ 27

Author(s):

Junsheng Nie ◽

Yougui Song ◽

John W. King ◽

Rui Zhang ◽

Xiaomin Fang

Keyword(s):

Grain Size ◽

Loess Plateau ◽

Remanent Magnetization ◽

Chinese Loess Plateau ◽

Joint Analysis ◽

Red Clay ◽

Chinese Loess ◽

Proxy Records ◽

Temperature And Precipitation ◽

The Chinese Loess Plateau

AbstractMagnetic grain-size variations have been used as sensitive paleoclimate proxies to investigate the evolution of the East Asian summer monsoon, but their relationship with temperature and precipitation is not entirely clear. Here we find that two magnetic grain-size proxy records (χARM/χLF and χARM/SIRM, where χARM, χLF and SIRM are anhysteretic remanent magnetization susceptibility, magnetic susceptibility measured at 470 Hz and saturation isothermal remanent magnetization, respectively) of Chinese loess and red-clay sediments co-vary during the last 6 Ma, except between ~ 4.5 and 2.6 Ma, when these two records had opposite trends. We attribute this disparate behavior to the different responses of χARM/χLF and χARM/SIRM to temperature and precipitation during ~ 4.5–2.6 Ma, when temperature and precipitation on the Chinese Loess Plateau were decoupled. A comparison of the loess and red-clay χARM/χLF and χARM/SIRM records with the global ice-volume proxy records reveals that χARM/χLF is more sensitive to temperature variations than χARM/SIRM. The results suggest that temperature on the Chinese Loess Plateau had a cooling trend from ~ 4.5 to ~ 2.6 Ma, whereas rainfall tended to increase. Our studies demonstrate that joint analysis of loess χARM/χLF and χARM/SIRM records can reveal paleoclimatic information that cannot be revealed by a single parameter.

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Climate Change and Vegetation Evolution during the Transition from Marine Isotope Stage 5 to 4 Based on Two Typical Profiles at the Southern Chinese Loess Plateau

Sustainability ◽

10.3390/su12041372 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1372

Author(s):

Tieniu Wu ◽

Huaqing Wu ◽

Henry Lin ◽

Tiantian Yang ◽

Xiaoyang Wu ◽

...

Keyword(s):

Grain Size ◽

Magnetic Susceptibility ◽

Loess Plateau ◽

Transitional Period ◽

Marine Isotope Stage ◽

Chinese Loess Plateau ◽

Forest Steppe ◽

Chinese Loess ◽

Southern Chinese ◽

Mis 5

The geological transitional period from the Marine Isotope Stage (MIS) 5 to 4 during the Quaternary period is a multidimensional change involving monsoon and precipitation variation, vegetation dynamics, and environmental evolution. The first loess layer (L1) and the first paleosol layer (S1) in the Chines Loess Plateau provide excellent high-resolution terrestrial sediment record for this transition. In this work, grain size (GS), CaCO3 content, magnetic susceptibility (MS), and pollen composition were measured at intervals of 2-cm in two representative L1/S1 profiles in the southern Chinese Loess Plateau to reconstruct records of climatic and vegetative changes during this transition. Our results showed that, in general, the paleo-vegetation type was forest-steppe, with Pinus being the commonest tree, and Chenopodiaceae and Artemisia being common herbs in the study area. The topography had a significant impact on the distribution of paleo-vegetation. The increase of coarse particles, the decrease of magnetic susceptibility, and the rising percentage of Gramineae, Artemisia and Chenopodiaceae pollen, all indicated that the paleoclimate became cooler and drier over the transitional period. Besides, we identified a cool event at about 76.8 ka B.P. as revealed by grain-size curves, and in response to this event, the vegetation changed significantly but lagged several hundred years behind the grain size record. This study confirmed the cooling and drying tendency during the MIS 5 to 4 transition phase in the southern margin of the Chinese Loess Plateau. These findings shed light on the climatic change on vegetation evolution during the MIS 5 to 4 transition period.

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The late Miocene and Pliocene climate in East Asia as recorded by grain size and magnetic susceptibility of the Red Clay deposits (Chinese Loess Plateau)

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/s0031-0182(03)00729-6 ◽

2004 ◽

Vol 204 (3-4) ◽

pp. 239-255 ◽

Cited By ~ 81

Author(s):

Jef Vandenberghe ◽

Huayu Lu ◽

Donghai Sun ◽

J.(Ko) van Huissteden ◽

Martin Konert

Keyword(s):

Grain Size ◽

Magnetic Susceptibility ◽

East Asia ◽

Loess Plateau ◽

Late Miocene ◽

Chinese Loess Plateau ◽

Red Clay ◽

Chinese Loess ◽

Clay Deposits

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Magnetic susceptibility record of Chinese Loess

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593300020794 ◽

1990 ◽

Vol 81 (4) ◽

pp. 263-288 ◽

Cited By ~ 159

Author(s):

G. Kukla ◽

Z. S. An ◽

J. L. Melice ◽

J. Gavin ◽

J. L. Xiao

Keyword(s):

Magnetic Susceptibility ◽

Oxygen Isotope ◽

Loess Plateau ◽

Deep Sea ◽

Chinese Loess Plateau ◽

Chinese Loess ◽

Low Field ◽

The Chinese Loess Plateau

ABSTRACTRecords of the low field magnetic susceptibility at three sites in the Chinese Loess Plateau, each with sediments covering the last 2·5 Ma, were averaged and combined into a single stacked file whose dating is independent of astronomic chronology. The stack reveals orbital frequencies, which are in general agreement with the astronomically tuned oxygen isotope deep sea chronology in the upper part of the Brunhes epoch, but disagree prior to 0·5 Ma ago.

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