| Автор | Eyre, John K. |
| Автор | Dickson, Domonic P. E. |
| Дата выпуска | 1995 |
| dc.description | Chinese loess has been analyzed in bulk, using Mössbauer spectroscopy, in order to investigate the effects of climate on the overall iron‐containing mineralogy. Strongly weathered loess is found to differ from weakly weathered loess in two significant respects. It contains a much larger content of fine‐grained (superparamagnetic) hematite and the ratio of paramagnetic Fe<sup>3+</sup>/Fe<sup>2+</sup> is substantially increased. The suggestion is that weathering results in the liberation of Fe from silicate minerals and the formation of fine‐grained hematite. Measurements of total iron content by atomic absorption spectrometry highlight that the strongly weathered loess has a higher content of iron than the weakly weathered loess, and that this is too large an effect to be explained by the leaching of carbonate. The indication is that the mineralogy of the dust input to the loess plateau varies as a function of climate. One possibility is that the grain size (and hence mineralogy) of the dust fluctuates in response to vegetational cover in proximal source areas. During interglacial times the vegetational cover would expand to stabilize these proximal sources, resulting in a bias to finer dust from more distant sources. Thus the mechanisms linking climate and mineralogy in the Chinese loess may be more complex than previously thought. |
| Формат | application.pdf |
| Копирайт | Copyright 1995 by the American Geophysical Union. |
| Тема | GEOMAGNETISM AND PALEOMAGNETISM |
| Тема | Rock and mineral magnetism |
| Тема | ATMOSPHERIC PROCESSES |
| Тема | Meteorology and Atmospheric Dynamics: Paleoclimatology |
| Тема | MINERALOGY AND PETROLOGY |
| Тема | Experimental mineralogy and petrology |
| Тема | MINERAL PHYSICS |
| Тема | NMR, Mossbauer spectroscopy, and other magnetic techniques |
| Название | Mössbauer spectroscopy analysis of iron‐containing minerals in the Chinese loess |
| Тип | article |
| DOI | 10.1029/95JB01060 |
| Electronic ISSN | 2156-2202 |
| Print ISSN | 0148-0227 |
| Журнал | Journal of Geophysical Research: Solid Earth |
| Том | 100 |
| Первая страница | 17925 |
| Последняя страница | 17930 |
| Выпуск | B9 |
| Библиографическая ссылка | Bowen, L. H., S. B.Weed, Mössbauer spectroscopy of soils and sediments, Chemical Mössbauer SpectroscopyR. H.Herber, Plenum, New York, 1984. |
| Библиографическая ссылка | Burbank, D. W., J.Li, Age and palaeoclimatic significance of the loess of Lanzhou, north China, Nature, 316, 429–431, 1985. |
| Библиографическая ссылка | Coey, J. M. D., Mössbauer spectroscopy of silicate minerals, Mössbauer Spectroscopy Applied to Inorganic ChemistryG. J.Long, , 1, chapt. 5, Plenum, New York, 1984. |
| Библиографическая ссылка | Evans, M. E., F.Heller, Magnetic enhancement and palaeoclimate: Study of a loess/palaeosol couplet across the Loess Plateau of China, Geophys. J. Int., 117, 257–264, 1994. |
| Библиографическая ссылка | Eyre, J. K., Magnetic mineralogy of Chinese 1oess, Ph.D. thesis,University of Liverpool,England,1994. |
| Библиографическая ссылка | Eyre, J. K., J.Shaw, Magnetic enhancement of Chinese 1oess — the role of gamma Fe<sub>2</sub>O<sub>3</sub>, Geophys. J. Int., 117, 265–271, 1994. |
| Библиографическая ссылка | Forster, T., M. E.Evans, F.Heller, The frequency dependence of low field susceptibility in 1oess sediments, Geophys. J. Int., 118, 636–642, 1994. |
| Библиографическая ссылка | Guo, Z., F.Nicolas, Z.An, Genetic types of the Holocene soil and the Pleistocene palaeosols in the Xifeng 1oess section in central China, Loess, Environment and Global ChangeT.Liu, 93–111, Science, New York, 1991. |
| Библиографическая ссылка | Guo, Z., N.Fedoroff, Z.An, T.Liu, Interglacial dustfall and origin of iron oxides‐hydroxides in the palaeosols of the Xifeng 1oess section, China, Sci. Geol. Sin., 21, 91–100, 1993. |
| Библиографическая ссылка | Han, J., J. J.Hus, R.Paepe, R. E.Vandenberghe, T.Liu, The rock magnetic properties of the Malan and Lishi formations in the loess plateau of China, Loess, Environment and Global ChangeT.Liu, 30–47, Science, New York, 1991. |
| Библиографическая ссылка | Heller, F., T.Liu, Palaeoclimate and sedimentary history from magnetic susceptibility of loess in China, Geophys. Res. Lett., 13, 1169–1172, 1986. |
| Библиографическая ссылка | Kukla, G., Z.An, Loess stratigraphy in Central China., Palaeogeogr. Palaeoclimatol. Palaeoecol., 72, 203–225, 1989. |
| Библиографическая ссылка | Oberteuffer, J. A., Magnetic separation: a review of principles, devices, and applications, IEEE Trans. Mag., MAG‐102, 223–238, 1974. |
| Библиографическая ссылка | Rea, D. K., The paleoclimatic record provided by eolian deposition in the deep sea: The geologic history of wind, Rev. Geophys., 322, 159–195, 1994. |
| Библиографическая ссылка | Robertson, D. J., D. E.France, Discrimination of remanence‐carrying minerals in mixtures, using isothermal remanent magnetisation acquisition curves, Phys. Earth Planet. Inter., 82, 223–234, 1994. |
| Библиографическая ссылка | Vandenberghe, R. E., E.De Grave, C.Landuydt, L. H.Bowen, Some aspects concerning the characterisation of iron oxides and hydroxides in soils and clays, Hyperfine Interactions, 53, 175–196, 1990. |
| Библиографическая ссылка | Vandenberghe, R. E., E.De Grave, J. J.Hus, J.Han, Characterisation of Chinese loess and associated palaeosol by Mossbauer spectroscopy, Hyperfine Interactions, 70, 977–980, 1992. |
| Библиографическая ссылка | Xu, L., T.Liu, M.Chen, B. A.Maher, S. K.Banerjee, Origin of magnetic minerals and magnetic susceptibility variations in Chinese loess, Loess, Environment and Global ChangeT.Liu, 279–288, Science, New York, 1991. |
| Библиографическая ссылка | Zheng, H., Z.An, J.Shaw, New contributions to Chinese Plio‐Pleistocene magnetostratigraphy, Phys. Earth Planet. Int., 70, 146–153, 1992. |
| Библиографическая ссылка | Zheng, H., F.Oldfield, L.Yu, J.Shaw, Z.An, The magnetic properties of particle‐sized samples from the Luochuan 1oess section: Evidence for pedogenesis, Phys. Earth Planet. Inter., 68, 250–258, 1991. |
