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Implication of Boron Isotope Geochemistry for the Pedogenic Environments in Loess and Paleosol Sequences of Central China

Published online by Cambridge University Press:  20 January 2017

Hai-Zhen Wei
Affiliation:
State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China
Fang Lei
Affiliation:
School of Geographic and Oceanographic Sciences, Jiangsu Collaborative Innovation Center for Climate Change, Nanjing University, Nanjing 210093, PR China
Shao-Yong Jiang*
Affiliation:
State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China State Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, PR China
Hua-Yu Lu*
Affiliation:
School of Geographic and Oceanographic Sciences, Jiangsu Collaborative Innovation Center for Climate Change, Nanjing University, Nanjing 210093, PR China
Ying-Kai Xiao
Affiliation:
Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810003, PR China
Han-Zhi Zhang
Affiliation:
School of Geographic and Oceanographic Sciences, Jiangsu Collaborative Innovation Center for Climate Change, Nanjing University, Nanjing 210093, PR China
Xue-Feng Sun
Affiliation:
School of Geographic and Oceanographic Sciences, Jiangsu Collaborative Innovation Center for Climate Change, Nanjing University, Nanjing 210093, PR China
*
*Correspondence to: S.-Y. Jiang, State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China.
*Correspondence to: S.-Y. Jiang, State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China.

Abstract

We investigated the boron isotopic composition in loess–paleosol sequences in five different profiles in the Chinese Loess Plateau. Three possible boron sources are identified: atmospheric input, carbonates, and weathered silicate rocks. Variations of [Sr], [B], δ11B and the magnetic susceptibility correlate well with the pedogenetic intensity in three out of the five studied profiles, where pedogenesis under a cold–dry climate indicates lower δ11B, lower [B], lower magnetic susceptibility and higher [Sr] values. Exceptions to the variations between the δ11B and other known proxies were observed in arenaceous soils and the Red Clay sequence: the former suggested that vertical redistribution probably occurred with the boron migration, and the latter indicated an unknown mechanism of susceptibility enhancement. A better correlation between the δ11B and magnetic susceptibility and the quantitative estimation of boron budget from each source confirms the influence of paleoenvironmental changes on boron geochemical cycle. Significant positive correlations in Sr/Ca vs. B/Ca and Mg/Ca vs. B/Ca reflect consistent enrichment behavior of those mobile elements into calcium carbonate. The preliminary results imply that boron isotopic compositions in soils can be a potential geochemical proxy to reconstruct the paleoenvironmental changes in loess–paleosol sequences.

Type
Research Article
Copyright
University of Washington

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References

Aggarwal, J.K., Sheppard, D., Mezger, K., and Pernicka, E. (2003). Precise and accurate determination of boron isotope ratios by multiple collector ICP-MS: origin of boron in the Ngawha geothermal system, New Zealand.. Chemical Geology 34., 331342.Google Scholar
Allison, N., Finch, A.A., EIMF, (2010). δ11B, Sr, Mg and B in a modern Porites coral: the relationship between calcification site pH and skeletal chemistry.. Geochimica et Cosmochimica Acta 74, 17901800.CrossRefGoogle Scholar
An, Z.S., Liu, T.S., Lou, Y.C., Porter, S.C., Kukla, G., Wu, X.H., and Hua, Y.M. (1990). The long-term paleomonsoon variation recorded by the loess–paleosol sequence in central China.. Quaternary International 7, (8), 9195.Google Scholar
Balsam, W., Ellwood, B., and Ji, J.F. (2005). Direct correlation of the marine oxygen isotopes record with the Chinese Loess Plateau iron oxide and magnetic susceptibility records.. Paleogeography, Paleoclimatology, Paleoecology 221, 141152.CrossRefGoogle Scholar
Barth, S. (1993). Boron isotope variations in nature: a synthesis.. Geologische Rundschau 82, 40651.CrossRefGoogle Scholar
Catanzaro, E.J., Champion, C.E., Garner, E.L., Malinenko, G.K., Sappenfield, M., and Shields, K.M. (1970). US National Bureau of Standards.. Special Publication, (26017., 70 pp).Google Scholar
Chen, J., An, Z.S., and Head, J. (1999). Variation of Rb/Sr ratios in the loess–paleosol sequences of central China during the last 130,000 years and their implications for monsoon paleoclimatology.. Quaternary Research 51, 215219.CrossRefGoogle Scholar
Chen, J., Wang, Y.J., Chen, Y., Liu, L.W., Ji, J.F., and Lu, H.Y. (2001). Rb and Sr geochemical characterization of the Chinese Loess and its implications for paleomonsoon climate.. Acta Geologica Sinica 75, 259266.Google Scholar
Chen, J., Chen, Y., Liu, L.W., Ji, J.F., Balsam, W., Sun, Y.B., and Lu, H.Y. (2006). Zr/Rb ratio in the Chinese loess sequences and its implication for changes in the East Asian winter monsoon strength.. Geochimica et Cosmochimica Acta 70, 14711482.CrossRefGoogle Scholar
Chetelat, B., and Gaillardet, J. (2005). Boron isotopes in the Seine River, France: a probe of anthropogenic contamination.. Environmental Science & Technology 39, 24862493.CrossRefGoogle Scholar
Chetelat, B., Liu, C.Q., Gaillardet, J., Wang, Q.L., Zhao, Z.Q., Liang, C.S., and Xiao, Y.K. (2009). Boron isotopes geochemistry of the Changjiang basin rivers.. Geochimica et Cosmochimica Acta 73, 60846097.CrossRefGoogle Scholar
Cividini, D., Lemarchand, D., Chabaux, F., Boutin, R., and Pierret, M.-C. (2010). From biogenical to lithogenical control of the B geochemical cycle in a forested watershed (Strengbach, Vosges).. Geochimica et Cosmochimica Acta 74, 31433163.CrossRefGoogle Scholar
Demuth, N., and Heumann, K.G. (1999). Determination of trace amounts of boron in rainwater by ICP-IDMS and NTI-IDMS and the dependence on meteorological and anthropogenic influences.. Journal of Analytical Atomic Spectrometry 14, 14491453.CrossRefGoogle Scholar
Goldberg, S. (1997). Reactions of boron with soils.. Plant and Soil 193, 3548.CrossRefGoogle Scholar
Goldberg, S. (1999). Reanalysis of boron adsorption on soils and soil minerals using the constant capacitance model.. Soil Science Society of America Journal 63, 823829.CrossRefGoogle Scholar
Goldberg, S., and Su, C. (2007). New advances in boron soil chemistry.. Advances in Plant and Animal Nutrition 313330.Google Scholar
Goldberg, S., Forster, H.S., and Heick, E.L. (1993). Boron adsorption mechanisms on oxides, clay minerals and soils inferred from ionic strength effects.. Soil Science Society of America Journal 57, 704708.CrossRefGoogle Scholar
Goldberg, S., Forster, H.S., Lesch, S.M., and Heick, E.L. (1996). Influence of anion competition on boron adsorption by clays and soils.. Soil Science 161, 99103.CrossRefGoogle Scholar
Guo, Z.T., Liu, T.S., and Guiot, J. (1996a). High frequency pulses of East Asia monsoon climate in the last two glaciations: link with the North Atlantic.. Climate Dynamics 12, 701709.CrossRefGoogle Scholar
Guo, Z.T., Fedoroff, N., and Liu, T.S. (1996b). Micromorphology of the loess–paleosol sequence of the last 130 ka in China and paleoclimatic events.. Science in China Series D 26, (5), 392398.Google Scholar
Guo, Z.T., Liu, T.S., Fedoroff, N., Wei, L.Y., Ding, Z.L., Wu, N.Q., Lu, H.Y., Jiang, W.Y., and An, Z.S. (1998). Climate extremes in loess of China coupled with the strength of deep-water formation in the North Atlantic.. Global and Planetary Change 18, 113128.CrossRefGoogle Scholar
Harvey, J., Garrido, C.J., Savov, I., Agostini, S., Padron-Navarta, J.A., Marchesi, C., Sanchez-Vizcaino, V.L., and Gomez-Pugnaire, M.T. (2014). 11B-rich fluids in subduction zones: the role of antigorite dehydration in subducting slabs and boron isotope heterogeneity in the mantle.. Chemical Geology 376, 2030.CrossRefGoogle Scholar
Heller, F., and Liu, T.S. (1982). Magnetostratigraphic dating of loess deposits in China.. Nature 300, 431433.CrossRefGoogle Scholar
Hemming, N.G., and Hanson, G.N. (1992). Boron isotopic composition and concentration in modern marine carbonates.. Geochimica et Cosmochimica Acta 56, 537543.CrossRefGoogle Scholar
Hemming, N.G., Guilderson, T.P., and Fairbanks, R.G. (1998). Seasonal variations in the boron isotopic composition of coral: a productivity signal?.. Global Biogeochemistry 12, 581586.CrossRefGoogle Scholar
Hogan, J.F., and Blum, J.D. (2003). Boron and lithium isotopes as groundwater tracers: a study at the Frech Kills Landfill, Staten Island, Now York, USA.. Applied Geochemistry 18, (4), 615627.CrossRefGoogle Scholar
Jiang, S.Y. (2010). Boron isotope geochemistry of hydrothermal ore deposits in China: a preliminary study.. Physics and Chemistry of the Earth, Part A 26, 851858.CrossRefGoogle Scholar
Jiang, S.Y., Palmer, M.R., and Yeats, C. (2002). Chemical and boron isotope compositions of tourmaline from the Archean Big Bell and Mount Gibson gold deposits, Murchison Province, Yilgarn Craton, Western Australia.. Chemical Geology 188, (3/4), 229247.CrossRefGoogle Scholar
Kasemann, S., Meixner, A., Erzinger, J., Viramonte, J., Alonso, R.N., and Franz, G. (2004). Boron isotope composition of geothermal fluids and borate minerals from salar deposits (central Andes/NW Argentina).. Journal of South American Earth Sciences 16, 685697.CrossRefGoogle Scholar
Kukla, G., Heller, F., Liu, X.M., Xu, T.C., Liu, T.S., and An, Z.S. (1988). Pleistocene climates in China dated by magnetic susceptibility.. Geology 16, 811814.2.3.CO;2>CrossRefGoogle Scholar
Lemarchand, E., Schott, J., and Gaillardet, J. (2007). How surface complexes impact boron isotope fractionation: evidence from Fe and Mn oxides sorption experiments.. Earth and Planetary Science Letters 260, 277296.CrossRefGoogle Scholar
Lemarchand, D., Cividini, D., Turpault, M.-P., and Chabaux, F. (2012). Boron isotopes in different grain size fractions: exploring past and present water–rock interactions from two soil profiles (Strengbach, Vosges Mountains).. Geochimica et Cosmochimica Acta 98, 7893.CrossRefGoogle Scholar
Liu, T.S. (1985). Loess and Environment. China Ocean Press, Beijing.Google Scholar
Liu, T.S., and Ding, Z.L. (1998). Chinese loess and the paleomonsoon.. Annual Review of Earth and Planetary Sciences 26, 111145.CrossRefGoogle Scholar
Liu, W.G., Peng, Z.C., Xiao, Y.K., and An, Z.S. (2002). Boron isotopic measurement of nodules in loess by using NTIMS.. Marine Geology & Quaternary Geology 22, 109122.(in Chinese with English abstract).Google Scholar
Liu, Y., Liu, W.G., Peng, Z.C., Xiao, Y.K., and Wei, G.J. (2009). Instability of seawater pH in the South China Sea during the mid–late Holocene: evidence from boron isotopic composition of corals.. Geochimica et Cosmochimica Acta 73, 12641272.CrossRefGoogle Scholar
Lu, H.Y., and An, Z.S. (1999). Comparison of grain-size distribution of red clay and loess–paleosol deposits in Chinese Loess Plateau.. Acta Sedimentologica Sinica 17, (2), 226232.(in Chinese with English abstract).Google Scholar
Lu, H.Y., and Sun, D.H. (2000). Pathways of dust input to the Chinese Loess Plateau during the last glacial and interglacial periods.. Catena 40, 251261.CrossRefGoogle Scholar
Lu, H.Y., Vandenberghe, J., and An, Z.S. (2001). Aeolian origin and palaeoclimatic implications of the ‘Red Clay’ (North China) as evidenced by grain-size distribution.. Journal of Quaternary Sciences 16, (1), 8997.3.0.CO;2-8>CrossRefGoogle Scholar
Lu, H.Y., and Zhou, J. (1996). Heinrich event and climate instability during the late glacial period.. Progress in Earth Science 11, 4045.(in Chinese with English abstract).Google Scholar
Lu, H.Y., Han, J.M., and Wu, N.Q. (1994). Analysis of the magnetic susceptibility in modern soils and its implication on paleoclimate.. Science in China Series D 24, 12901297.Google Scholar
Lu, H.Y., Liu, X.D., Zhang, F.Q., An, Z.S., and Dodson, J. (1999). Astronomical calibration of loess–paleosol deposits at Luochuan, central Chinese Loess Plateau.. Paleogeography, Paleoclimatology, Paleoecology 154, 237246.CrossRefGoogle Scholar
Lu, H.Y., Zhang, F.Q., Liu, X.D., and Duce, R. (2004). Periodicities of paleoclimatic variations recorded by loess–paleosol sequence in China.. Quaternary Science Reviews 23, 18911900.CrossRefGoogle Scholar
Lu, H.Y., Zhou, Y.L., Liu, W.G., and Mason, J. (2012). Organic stable carbon isotopic composition reveals late Quaternary vegetation changes in the dune fields of northern China.. Quaternary Research 77, 433444.CrossRefGoogle Scholar
Maher, B.A., and Thompson, R. (1995). Paleorainfall reconstructions from pedogenic magnetic susceptibility variations in the Chinese loess and paleosols.. Quaternary Research 44, 383391.CrossRefGoogle Scholar
Malek, M.A., Kim, B., Jung, H., Song, Y., and Ro, C. (2011). Single-particle mineralogy of Chinese soil particles by the combined use of low-Z particle electron probe X-ray microanalysis and attenuated total reflectance-FT-IR imaging techniques.. Analytical Chemistry 83, 79707977.CrossRefGoogle ScholarPubMed
Marschall, H.R., and Jiang, S.Y. (2011). Tourmaline isotopes: no element left behind.. Elements 7, 313319.CrossRefGoogle Scholar
Martinson, D.G., Pisias, N.G., Hays, J.D., Imbrie, J., Moore jr., T.C., and Shackleton, N.J. (1987). Age dating and the orbital theory of the ice ages: development of a high-resolution 0 to 300,000- year chronostratigraphy.. Quaternary Research 27, 129.CrossRefGoogle Scholar
Muttik, N., Kirsimäe, K., Newsom, H.E., and Williams, L.B. (2011). Boron isotope composition of secondary smectite in suevites at the Ries crater, Germany: boron fractionation in weathering and hydrothermal processes.. Earth and Planetary Science Letters 310, 244251.CrossRefGoogle Scholar
Nesbitt, H.W., and Young, G.M. (1982). Early Proterozoic climates and plate motions inferred from major element chemistry of lutites.. Nature 299, 715717.CrossRefGoogle Scholar
Palmer, M.R., and Pearson, P.N. (2003). A 23,000-year record of surface water pH and PCO2 in the western equatorial Pacific Ocean.. Science 300, 480482.CrossRefGoogle ScholarPubMed
Palmer, M.R., and Swihart, G.H. (1996). Boron isotope geochemistry: an overview.. Reviews in Mineralogy and Geochemistry 33, 709744.Google Scholar
Palmer, M.R., Spivack, A.J., and Edmond, J.M. (1987). Temperature and pH controls over isotopic fractionation during adsorption of boron on marine clay.. Geochimica et Cosmochimica Acta 51, 23192323.CrossRefGoogle Scholar
Palmer, M.R., Pearson, P.N., and Cobb, S.J. (1998). Reconstructing past ocean pH-depth profiles.. Science 282, 14681471.CrossRefGoogle ScholarPubMed
Petelet-Giraud, E., Klaver, G., and Negrel, P.J. (2009). Natural versus anthropogenic sources in the surface- and groundwater dissolved load of the Dommel river (Meuse basin): constraints by boron and strontium isotopes and gadolinium anomality.. Journal of Hydrology 369, 336349.CrossRefGoogle Scholar
Qiang, X.K., An, Z.S., and Chang, H. (2003). Paleoclimatic implication of frequency-dependent magnetic susceptibility of red clay sequences in the Jiaxian Profile of Northern China.. Marine Geology & Quaternary Geology 23, (3), 9196.Google Scholar
Rose-Koga, E.F., Chaussidon, M., and France-Larnord, C. (2000). Fractionation of boron isotopes during erosion processes: the example of Himalayan rivers.. Geochimica et Cosmochimica Acta 64, (3), 397408.CrossRefGoogle Scholar
Rose-Koga, E.F., Sheppard, S., Chaussidon, M., and Carigna, J. (2006). Boron isotopic composition of atmospheric precipitations and liquid–vapour fractionations.. Geochimica et Cosmochimica Acta 70, 16031615.CrossRefGoogle Scholar
Spivack, A.J., and You, C.F. (1997). Boron isotopic geochemistry of carbonates and pore waters, Ocean Drilling Program Site 851.. Earth and Planetary Science Letters 152, 113122.CrossRefGoogle Scholar
Spivack, A.J., Palmer, M.R., and Edmond, J.M. (1987). The sedimentary cycle of the boron isotopes.. Geochimica et Cosmochimica Acta 51, 10331043.CrossRefGoogle Scholar
Stevens, T., and Lu, H.Y. (2010). Radiometric dating of the late Quaternary summer monsoon on the Loess Plateau, China.. Geological Society, London, Special Publications 342, (1), 87108.CrossRefGoogle Scholar
Su, C., and Suarez, D.L. (1995). Coordination of adsorbed boron: a FTIR spectroscopic study.. Environmental Science & Technology 29, 302311.CrossRefGoogle Scholar
Sun, J.M., and Liu, T.S. (2000). Multiple origins and interpretations of the magnetic susceptibility signal in Chinese wind-blown sediments.. Earth and Planetary Science Letters 180, 287296.CrossRefGoogle Scholar
Sun, Y.B., Sun, D.H., and An, Z.S. (2001). Paleoclimatic implication of frequency dependent magnetic susceptibility of red clay–loess–paleosol sequences in the Lingtai Profile.. Geological Journal of China University 7, (3), 301306.(in Chinese with English abstract).Google Scholar
Tan, H.B., Ma, H.Z., Lu, H.Y., Zhang, X.Y., Li, Z., and Zhou, D.J. (2002). Paleoclimate significance of Sr and CaO in acid-soluble fraction of high plateau loess deposit in Xining Basin.. Geochimica 31, (5), 409414.Google Scholar
Tonarini, S., Dantonio, M., Di, Vito M.A., Orsi, G., and Carandente, A. (2009). Geochemical and B–Sr–Nd isotopic evidence for mingling and mixing processes in the magmatic system that fed the Astroni volcano (4.1–3.8 ka) within the Campi Flegrei caldera (southern Italy).. Lithos 107, 135151.CrossRefGoogle Scholar
Vandenberghe, J., An, Z., Nugteren, G., Lu, H., and Huissteden, K.V. (1997). New absolute time scale for the Quaternary climate in the Chinese loess region by grain-size analysis.. Geology 25, 3538.2.3.CO;2>CrossRefGoogle Scholar
Wang, Q.Z., Xiao, Y.K., Wang, Y.H., Zhang, C.G., and Wei, H.Z. (2002). Boron separation by the two-step ion-exchange for the isotopic measurement of boron.. Chinese Journal of Chemistry 20, 4550.CrossRefGoogle Scholar
Wei, G.J., McCulloch, M.T., Mortimer, G., Deng, W., and Xie, L. (2009). Evidence for ocean acidification in the Great Barrier Reef of Australia.. Geochimica et Cosmochimica Acta 73, 23322346.CrossRefGoogle Scholar
Wei, H.Z., Jiang, S.Y., Hemming, N.G., Wu, H.P., Yan, X., Yang, J.H., Pu, W., and Yang, T. (2014a). An improved procedure for separation/purification of boron from complex matrices and high-precision measurement of boron isotopes by PTIMS and MC-ICP-MS.. Talanta 123, 151160.CrossRefGoogle Scholar
Wei, H.Z., Jiang, S.Y., Tan, H.B., Zhang, W.J., Li, B.K., and Yang, T.L. (2014b). Boron isotope geochemistry of salt sediments from the Dongtai salt lake in Qaidam Basin: boron budget and sources.. Chemical Geology 380, 7483.CrossRefGoogle Scholar
Wen, Q.Z. (1989). The Geochemistry of Chinese Loess. Science Press in Beijing, (in Chinese).Google Scholar
Widory, D., Petelet-Giraud, E., Ne, Grel P., and Ladouche, B. (2005). Tracking the sources of nitrate in groundwater using coupled nitrogen and boron isotopes: a synthesis.. Environmental Science & Technology 39, 539548.CrossRefGoogle ScholarPubMed
Williams, L.B., and Hervig, R.L. (2004). Boron isotope composition of coals: a potential tracer of organic contaminated fluids.. Applied Geochemistry 19, (10), 16251636.CrossRefGoogle Scholar
Williams, L.B., and Hervig, R.L. (2005). Lithium and boron isotopes in illite/smectite: the importance of crystal size.. Geochimica et Cosmochimica Acta 69, 57055716.CrossRefGoogle Scholar
Williams, L.B., Hervig, R.L., and Hutcheon, I. (2001). Boron isotope geochemistry during diagenesis. Part II. Applications to organic-rich sediments.. Geochimica et Cosmochimica Acta 1783–1794, .Google Scholar
Xiao, Y.K., Li, S.Z., Wei, H.Z., Sun, A.D., Liu, W.G., Zhou, W.J., Zhao, Z.Q., Liu, C.Q., and Swihart, G.H. (2007). Boron isotopic fractionation during seawater evaporation.. Marine Chemistry 103, 382392.CrossRefGoogle Scholar
Xiao, J., Xiao, Y.K., Jin, Z.D., He, M.Y., and Liu, C.Q. (2013). Boron isotope variations and its geochemical application in nature.. Australian Journal of Earth Sciences 60, 431447.CrossRefGoogle Scholar
Xie, Q.Q., Chen, T.H., Sun, Y.B., Li, X.X., and Xu, X.X. (2008). Composition of ferric oxides in the Luochuan Loess–Red Clay sequences on China's Loess Plateau and its plaeoclimatic implications.. Acta Mineralogica Sinica 28, (4), 389396.(in Chinese with English abstract).Google Scholar
Xu, Z.F., Li, Y.S., Tang, Y., and Han, G.L. (2009). Chemical and strontium isotope characterization of rainwater at an urban site in Loess Plateau, Northwest China.. Atmospheric Research 94, 481490.CrossRefGoogle Scholar
Yan, X., Jiang, S.Y., Wei, H.Z., Yan, Y., Wu, H.P., and Pu, W. (2012). Extraction and determination of boron isotopic composition in tourmalines.. Chinese Journal of Analytical Chemistry 40, (11), 16541660.CrossRefGoogle Scholar
Yu, J.M., Foster, G.L., Elderfield, H., Broecker, W.S., and Clark, E. (2010). An evaluation of benthic foraminiferal B/Ca and δ11B for deep ocean carbonate ion and pH reconstructions.. Earth and Planetary Science Letters 293, 114120.CrossRefGoogle Scholar
Yuan, J., Guo, Q., and Wang, Y. (2014). Geochemical behaviors of boron and its isotopes in aqueous environment of the Yangbaijing and Yangyi geothermal fields, Tibet, China.. Journal of Geochemical Exploration 140, 1122.CrossRefGoogle Scholar
Zhao, Z.Q., and Liu, C.Q. (2010). Anthropogenic inputs of boron into urban atmosphere: evidence from boron isotopes of precipitations in Guiyang City, China.. Atmospheric Environment 44, 41654171.CrossRefGoogle Scholar
Zhao, Z.Q., Liu, C.Q., Xiao, Y.K., and Lang, Y.C. (2003). Geochemical study of boron isotopes in the process of loess weathering.. Science in China Series D 2, 106116.CrossRefGoogle Scholar
Zhou, L.P., Oldfield, F., Wintle, A.G., Robinson, S.G., and Wang, J.T. (1990). Partly pedogenic origin of magnetic variations in Chinese loess.. Nature 346, 7779.CrossRefGoogle Scholar
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