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קהילה:
אסיף מאגר המחקר החקלאי
פותח על ידי קלירמאש פתרונות בע"מ -
Pedogenic and lithogenic contributions to the magnetic susceptibility record of the Chinese loess/palaeosol sequence
Year:
1995
Source of publication :
Geophysical Journal International
Authors :
פיין, פנחס
;
.
Volume :
122
Co-Authors:
Fine, P., Institute of Soils and Water, Volcani Center, ARO, Bet Dagan, 50250, Israel
Verosub, K.L., Department of Geology, University of California, Davis, California, 95616, United States
Singer, M.J., Department of Land, Air and Water Resources, University of California, Davis, California, 95616, United States
Facilitators :
From page:
97
To page:
107
(
Total pages:
11
)
Abstract:
We have studied the magnetic properties of 69 loess and palaeosol samples from the loess plateau in China. Our methodology involves the combination of differential dissolution of secondary iron oxides and oxyhydroxides using citrate‐bicarbonate‐dithionite (CBD) with measurements of magnetic parameters. Because most of these parameters are additive, we can use pre‐ and post‐CBD values to determine the mineral magnetic properties of the CBD‐soluble material. We can also calculate the partitioning of iron among various phases. Approximately two‐thirds of the total iron in our samples exists as paramagnetic iron in silicate minerals. Anti‐ferromagnetic material (haematite) constitutes almost all of the remainder. However, the magnetic susceptibility record of the loess/palaeosol sequence arises primarily from a small amount of iron in ferrimagnetic phases. This iron consists of a CBD‐resistant component which represents multidomain grains inherited from the parent material of the loess, and a CBD‐soluble component which represents grains near the superparamagnetic/single domain boundary. The first component appears in nearly uniform amounts throughout the loess column and is the dominant ferrimagnetic phase in the magnetically less‐enhanced loess. Accumulation of the second component in the palaeosols gives rise to the magnetic susceptibility enhancement of the loess column. The magnetic properties of the CBD‐soluble component indicate that it formed as a result of in situ pedogenesis, which confirms our earlier conclusion that the palaeoclimate record of the loess/palaeosol sequence at the sites that we have sampled is primarily a record of pedogenesis. Copyright © 1995, Wiley Blackwell. All rights reserved
Note:
Related Files :
CBD
iron transformations
loess
magnetic susceptibility
palaeoclimate
palaeosol
palaeosols
עוד תגיות
תוכן קשור
More details
DOI :
10.1111/j.1365-246X.1995.tb03539.x
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
28323
Last updated date:
02/03/2022 17:27
Creation date:
17/04/2018 00:38
Scientific Publication
Pedogenic and lithogenic contributions to the magnetic susceptibility record of the Chinese loess/palaeosol sequence
122
Fine, P., Institute of Soils and Water, Volcani Center, ARO, Bet Dagan, 50250, Israel
Verosub, K.L., Department of Geology, University of California, Davis, California, 95616, United States
Singer, M.J., Department of Land, Air and Water Resources, University of California, Davis, California, 95616, United States
Pedogenic and lithogenic contributions to the magnetic susceptibility record of the Chinese loess/palaeosol sequence
We have studied the magnetic properties of 69 loess and palaeosol samples from the loess plateau in China. Our methodology involves the combination of differential dissolution of secondary iron oxides and oxyhydroxides using citrate‐bicarbonate‐dithionite (CBD) with measurements of magnetic parameters. Because most of these parameters are additive, we can use pre‐ and post‐CBD values to determine the mineral magnetic properties of the CBD‐soluble material. We can also calculate the partitioning of iron among various phases. Approximately two‐thirds of the total iron in our samples exists as paramagnetic iron in silicate minerals. Anti‐ferromagnetic material (haematite) constitutes almost all of the remainder. However, the magnetic susceptibility record of the loess/palaeosol sequence arises primarily from a small amount of iron in ferrimagnetic phases. This iron consists of a CBD‐resistant component which represents multidomain grains inherited from the parent material of the loess, and a CBD‐soluble component which represents grains near the superparamagnetic/single domain boundary. The first component appears in nearly uniform amounts throughout the loess column and is the dominant ferrimagnetic phase in the magnetically less‐enhanced loess. Accumulation of the second component in the palaeosols gives rise to the magnetic susceptibility enhancement of the loess column. The magnetic properties of the CBD‐soluble component indicate that it formed as a result of in situ pedogenesis, which confirms our earlier conclusion that the palaeoclimate record of the loess/palaeosol sequence at the sites that we have sampled is primarily a record of pedogenesis. Copyright © 1995, Wiley Blackwell. All rights reserved
Scientific Publication
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