| 第四纪红土的磁性与氧化铁矿物学特征及其古环境意义 |
| |
| 引用本文： | 卢升高.第四纪红土的磁性与氧化铁矿物学特征及其古环境意义[J].土壤学报,2000,37(2):182-191. |
| |
| 作者姓名： | 卢升高 |
| |
| 作者单位： | 浙江大学环境与资源学院，杭州 310029 |
| |
| 基金项目： | 国家自然科学基金资助项目(项目批准号：49301010) |
| |
| 摘 要： | 应用矿物磁测，Ｘ－衍射和电镜技术对浙江省第四纪红土的磁性与氧化铁矿物学特征进行了研究。结果表明，均质层和网纹层的磁化率（χ）、频率磁化率（χｆｄ）、软剩磁（ＳｏｆｔＩＲＭ）、非滞后剩磁（ＡＲＭ）、饱和等温剩磁（ＳＩＲＭ）和剩磁矫顽力（（Ｂｏ）ｃｋ）等磁性参数存在明显差异，均质层的磁化率和饱和等温剩磁分别是网纹层的６倍和４倍；第四纪红土的磁化率主要由风化成土作用产生的超顺磁性颗粒（ＳＰ）和稳定单畴颗
|
| 关 键 词： | 第四纪红土 磁性 氧化铁 环境变迁 环境磁学 |
| 收稿时间： | 2/6/1999 12:00:00 AM |
| 修稿时间： | 1999年2月6日 |
CHARACTERIZATION OF MAGNETISM AND IRON OXIDE MINERALS OF QUATERNARY RED EARTH AND ITS PALEOENVIRONMENTAL IMPLICATIONS |
| |
| Lu Sheng-gao.CHARACTERIZATION OF MAGNETISM AND IRON OXIDE MINERALS OF QUATERNARY RED EARTH AND ITS PALEOENVIRONMENTAL IMPLICATIONS[J].Acta Pedologica Sinica,2000,37(2):182-191. |
| |
| Authors: | Lu Sheng-gao |
| |
| Institution: | College of Natural Assource and Environmental Science, Zhejiang University, Hangzhou 310029 |
| |
| Abstract: | Characterization of magnetism and iron oxide minerals for Quaternary red earth was investigated by mineral magnetic measurements, X-ray powder diffraction and transmission electron microscopy. The data indicated that there were significant differences in magnetic susceptibility (χ), frequency dependent susceptibility (χfd),anhysteretic remanent magnetization, saturation isothermal remanent magnetization (SIRM) and demagnetization parameters between homogeneous horizon and reticular horizon for red earth. It was found that χ and SIRM of homogenous horizon were six and four times more than that of reticular horizon, respectively. Magnetic susceptibility of red earth mostly come from the contribution of pedogenetic ferrimagnetic minerals that were superparamagnetic (SP) and stable-single domain (SSD)grains. It was found that χ of red earth was highly significantly correlated with χfd and ARM values. Following dithionite-citrate bicarbonate (DCB) treatment, χ loss amount for homogeneous horizon was significantly greater than that for reticular horizon. Magnetic susceptibility removed by DCB has been attributed to presence of the secondary SP and SSD grains. Based on the acquisition curves of IRM, demagnetization curves, X-diffraction pattern and morphology observation, iron oxide minerals for red earth were comprised of hematite, maghmatite andgoethite. We suggest that concentration, grains size and mineral assemblage of ferrimagnetic phase be reflection and signature of the Quaternary environmental changes. It can be concluded that χ, χfd, χ and χfd removed by DCB treatment were increased with increasing red earthening. Thus, these differences are considered effective indicators for the quantitative study of the environmental fluctuations recorded by the Quaternary red earth. |
| |
| Keywords: | Quaternary red earth Magnetic susceptibility Frequent dependent susceptibility Magnetic minerals Environmental changes |
| 本文献已被 维普 万方数据 等数据库收录！ |
| 点击此处可从《土壤学报》浏览原始摘要信息 |
| 点击此处可从《土壤学报》下载免费的PDF全文 |
|
