Research Advances in ESR Provenance Tracing Methods of Quartz in Sediments

The ESR (Electron Spin Resonance) signals of quartz is a newly developed sediment provenance tracing method. In this paper, the various ESR signals in quartz, historical development of quartz ESR signals in sediment provenance tracing, thermal stability characteristics of heat treated E’ center, the potential use of quartz nature E’ center and the irradiated Al/Ti center, as well as successful applications in aeolian sediments, river sediments and marine sediments provenance tracing, were briefly reviewed. The most useful ESR centers of quartz include the heat treated E’ center, the nature E’ center, the Al center and the Ti center. According to recent application researches, the heat-treated E’ center is the most commonly practiced among them while the significance of provenance tracing by Al and Ti centers are still in experimental and theoretical stage. Moreover, nature signal intensities of quartz E’ center not only show a significant dependence on lithology both in bedrocks and deposits, but also can reflect the mixture ratio of deposits with different types of sourced bedrocks. As for the study objects, this method has been successfully used in the studies of provenance area of East Asian dust, the temporal and spatial changes of Loess Plateau provenance, the provenance change of aeolian sediment over time and space on Japanese Islands, as well as sediment provenance tracing of Japan Sea sediments. In addition, the ESR provenance tracing of quartz has promising application prospect in quantitative and semi-quantitative analysis of fluvial sediment provenance tracing. Along with the development of ESR dating, this method can significantly reflect and reconstruct the relationship among regional tectonic movements, geomorphic evolution, and climate evolution. In future work, the combination of trace elements provenance tracing and ESR signals provenance tracing in quartz will help improve and promote the development of sediments provenance tracing methods.     

中国沙漠物源研究:回顾与展望

沙漠物源研究不仅在风沙地貌学上有重大的理论和实践意义,而且对联结大气粉尘排放、黄土堆积、气候系统和海洋生物地球化学循环也有重要价值。在简要回顾中国沙漠研究的基础上,梳理了中国沙漠物源研究的理论、方法和主要成果,结合国际上沉积物物源分析的趋向,指出目前世界沙漠物源的研究都是基于沉积物组份属性统计的反演模型,这种研究范式在数据获取、处理与解释方面存在缺陷,如沉积物的取样设计与测试分析、未消除"粒级依赖"对沉积物组份影响、数据未进行对数变换、忽视Dickinson图解应用的前提条件等。提出今后中国沙漠物源研究的方向:①采用正确统一的取样设计和分析方法对各沙漠的沉积物组份属性进行系统研究,建立中国沙漠沉积物组份的属性数据库;②选择若干典型沙漠,利用其周边山地详尽的地质构造、母岩和气候数据,定量构建沉积物生成的正演模型,模拟源区生成沉积物的数量、成分和结构,并用建成的沉积物组份属性数据验证和校正;③定量评估河流冲积物、冲积-湖积物、洪积-冲积物和基岩风化的残积、坡积物对中国各沙漠物源的贡献率与迁移路径,研究中国各沙漠中细颗粒物质的形成机制,对比中国沙漠与低纬度沙漠物源的形成机制;④定量研究历史和地质时间尺度沙漠-黄土-深海沉积物物源的内在联系及其驱动因素,建立陆地-大气-海洋物质循环的机理模型。     

Aeolian Deposits in the Yarlung Zangbo River Basin,Southern Tibetan Plateau: A Brief Review

The Yarlung Zangbo River is located in the southern Tibetan Plateau. Loess since the geological history and modern aeolian sand dunes are widely developed in the basin, bearing rich information on the aeolian processes and environmental evolution. In this work, we reviewed the main research progress of aeolian deposits in the Yarlung Zangbo River basin in recent years, and discussed the distribution characteristics, accumulation age, sediment characteristics and provenance and the possible formation mechanism of aeolian deposits and the history of aeolian activity. The results show that loess is mainly developed on the river’s terraces and some of the hilltops, and mostly formed since the last glacial maximum and mainly developed since Marine Isotope Stage 1 (about 14 ka BP), while aeolian sand deposit is mainly developed in the river’s wide valley, with relatively short accumulation time. The sediment particles mainly underwent mechanical transport and physical weathering, but chemical weathering was weak. Although the physical and chemical properties of sediments show some spatial changes, there still exist obvious local characteristics, which are closely related to the nearby surface sediments. Under the background of aeolian source, the local-source genesis of loess is generally recognized. The surface loose material at the bottom of valley is main material source of aeolian deposits. The evolution of aeolian activity is relatively complex. In addition to the regional climate change, the local environment is also an important factor affecting the aeolian activity and its regional difference. Based on the previous studies, we suggest that the systematic study on the physical and chemical properties of aeolian sediments, climate change since the Holocene and the impact of dust emission on human living environment should be strengthened in the future research.     

基于碎屑锆石的黄土高原—毛乌素交界区石峁黄土粉尘物源估算*

对于黄土高原粉尘物质的来源以及沙漠和河流对粉尘的贡献,仍未达成一致的认识。本研究以毛乌素东神木市石峁剖面为研究对象,利用碎屑锆石年龄谱,对末次冰消期以来的风成粉尘堆积和河流沉积物展开源区分析,并使用逆蒙特卡罗模型进行物源的定量计算。结果显示,粒径分布和阴极发光(CL)图像显示石峁黄土为典型风成沉积。其粗颗粒碎屑锆石(>40 μm)年龄峰值集中在190~300 Ma、300~600 Ma、1700~1900 Ma和2300~2600 Ma,年龄谱显示近源(局地基岩碎屑)、中源(黄河河沙)和远源(阿拉善地区沙漠)均有贡献; 定量计算表明,三者分别贡献71%、21%和8%的风成粗颗粒。中、近源中,黄河及其支流侵蚀基岩后搬运沉积的漫滩物质成为粉尘输移的中转站,为黄土的形成提供了主要的物源。光释光测年结果表明,石峁剖面河流沉积物及其上覆的黄土物质分别形成于倒数第2次冰消期和末次冰消期,两者之间的沉积间断可能指示了末次冰期至冰消期的侵蚀事件,导致了河滩物质暴露,从而形成了潜在的局地尘源。这些结果表明,包括黄河干支流在内的河流系统对黄土粉尘有重要的物源贡献。     

基于碎屑锆石的黄土高原—毛乌素交界区石峁黄土粉尘物源估算*

对于黄土高原粉尘物质的来源以及沙漠和河流对粉尘的贡献,仍未达成一致的认识。本研究以毛乌素东神木市石峁剖面为研究对象,利用碎屑锆石年龄谱,对末次冰消期以来的风成粉尘堆积和河流沉积物展开源区分析,并使用逆蒙特卡罗模型进行物源的定量计算。结果显示,粒径分布和阴极发光(CL)图像显示石峁黄土为典型风成沉积。其粗颗粒碎屑锆石(>40 μm)年龄峰值集中在190~300 Ma、300~600 Ma、1700~1900 Ma和2300~2600 Ma,年龄谱显示近源(局地基岩碎屑)、中源(黄河河沙)和远源(阿拉善地区沙漠)均有贡献; 定量计算表明,三者分别贡献71%、21%和8%的风成粗颗粒。中、近源中,黄河及其支流侵蚀基岩后搬运沉积的漫滩物质成为粉尘输移的中转站,为黄土的形成提供了主要的物源。光释光测年结果表明,石峁剖面河流沉积物及其上覆的黄土物质分别形成于倒数第2次冰消期和末次冰消期,两者之间的沉积间断可能指示了末次冰期至冰消期的侵蚀事件,导致了河滩物质暴露,从而形成了潜在的局地尘源。这些结果表明,包括黄河干支流在内的河流系统对黄土粉尘有重要的物源贡献。     

Geochemical characteristics of fine and coarse fractions of sediments in the Yarlung Zangbo River Basin (southern Tibet,China)

Tracing sources of aeolian sediment is key to reconstructing earth surface processes in arid areas and interpreting the paleoenvironmental significance of aeolian sequences. However, the difference of geochemical characteristics between different fractions of sediments in the Yarlung Zangbo River Basin (YZRB) is still unclear, so we want to identify which fraction of sediments is more suitable for tracing sediment sources. Considering the long distance between different wide valleys in the YZRB, we wonder whether there is any difference between these wide valleys in terms of geochemical characteristics of sediments. Forty-three surface sediment samples in the YZRB are collected, and the grain-size distributions and the major-element composition for 37 samples and the trace and rare earth element composition for the coarse (75–500 μm) and fine (<?75 μm) fractions of all samples are determined. The results reveal the following: (1) the fine fractions of the deposits contain more environmental information, suggesting that the fine fractions cannot be directly compared between different climate zones for provenance identification and that appropriate coarse fractions, based on the grain-size distribution of the targeted sediments, are more ideal for tracing sediment sources; and (2) geochemical characteristics of various sediment types show spatial heterogeneity. The coarse and fine fractions of the loose sediment samples can be divided into two regional groups based on geochemical characteristics: the Maquanhe zone in the upper reach, the Xigaze, Shannan and Mainling zone in the middle reach, which is consistent with the geological background of the YZRB; (3) aeolian deposits in the YZRB are a local origin and predominantly derived from the adjacent loose sediments, and fluvial sediments in the upper reach contribute little to the aeolian sands in the middle reach.     

碎屑矿物热年代学研究进展

碎屑矿物热年代学是以沉积物中未遭受热重置的碎屑矿物颗粒为研究对象,将造山带抬升、剥露和盆地沉积联系起来的年代学方法。在物源分析、源区构造热历史、古地形恢复和约束地层年龄等方面有广泛的应用。在概述其基本原理的基础上,从造山带剥露历史分析、物源分析中多种技术的联合运用和现代汇水区侵蚀速率计算3个方面介绍了这一方法近年来的研究进展。     

http://www.sciencedirect.com/science/article/pii/S1674987114000693

The Yangtze River is one of the most important components of the East Asia river system.In this study,sediments in the Jianghan Basin,middle Yangtze River,were selected for trace element and rare earth element(REE)measurements,in order to decipher information on the change of sediment provenance and evolution of the Yangtze River.According to the elemental variations,the late Cenozoic sediments of the Jianghan Basin could be divided into four parts.During 2.68e2.28 Ma and 1.25e0 Ma,provenance of the sediments was consistent,whereas sediments were derived from variable sources during2.28e1.25 Ma.Comparison of the elemental compositions between the Pliocene and Quaternary sediments revealed a change in sediment source from a more felsic source area to a more basic source area around the PlioceneeQuaternary boundary.Input from the Emeishan LIP should account for this provenance change.Based on the provenance analysis of sediments in the Jianghan Basin,we infer that the Yangtze River developed into a large river with its drainage basin extended to the Emeishan LIP no later than the PlioceneeQuaternary boundary.     

青藏高原典型地区沉积物地球化学特征与矿物组成的粒度效应

地表松散沉积物中不同粒级的颗粒蕴含着不同的信息,这种差异与其物质来源、搬运和沉积过程中的分选作用以及沉积后的风化作用等有关。因此,可根据沉积物中不同粒级颗粒地球化学特征与矿物组成的差异,进行沉积物物源追踪或沉积环境重建。选择青藏高原在气候和地貌方面具有典型意义的柴达木盆地、错那湖、雅鲁藏布江流域作为研究区,分别采集了这几个地区的沙丘沙、黄土、湖积物、冲积物、洪积物、残坡积物等地表松散沉积物样品,用干筛法将沉积物样品分为两个部分,粗颗粒部分粒径范围为≥75~500 μm,细颗粒部分粒径<75 μm。对上述粗、细颗粒分别进行稀土与微量元素、Sr-Nd同位素、轻矿物组成的实验室分析测试,并对沉积物中粗、细颗粒的测试结果采用古典多维尺度方法进行相似性分析。结果表明：青藏高原松散沉积物中粗、细颗粒在轻矿物组成、微量和稀土元素含量、稀土特征、元素参数等方面存在差异;细颗粒部分蕴含了更多的环境信息,富含容易受化学风化影响的黏土矿物以及硬度较小、容易被磨蚀的方解石等矿物。在物源示踪中不同气候区的沉积物细颗粒不宜进行直接比较,应根据样品的粒度分布情况优先选择合适的粗颗粒组分进行物源示踪。     

Sediment provenance of late Quaternary morainic,fluvial and loess‐like deposits in the southwestern Verkhoyansk Mountains (eastern Siberia) and implications for regional palaeoenvironmental reconstructions

A provenance analysis of late Quaternary deposits from tributaries of the Aldan and Lena rivers in Central Yakutia (eastern Siberia) was carried out using analysis of heavy minerals and clay mineralogy. Cluster analysis revealed one assemblage that is characterized by relatively high proportions of amphibole, orthopyroxene and garnet as well as pedogenic clay minerals, reflecting a sediment provenance from the wide catchment area of the Lena and Aldan rivers. In contrast, the three other clusters are dominated by stable heavy minerals with varying amounts of clinopyroxene, apatite and garnet, as well as high percentages of illite and chlorite that are indicative of source rocks of the Verkhoyansk Mountains. Glacial moraines reveal the local mountain source signal that is overprinted by the Lena‐Aldan signal in the oldest moraines by reworking processes. Alluvial sediments in the Verkhoyansk Foreland show a clear Lena source signal through intervals of the middle and late Pleistocene, related to a stream course closer to the mountains at that time. Loess‐like cover sediments are characterized by the dominant Lena provenance with increasing proportions of local mountain sources towards the mountain valleys. Aeolian sands in an alluvial terrace section at the mountain margin covering the time between 30 ka and 10 ka BP reflect temporarily dominant inputs of aeolian materials from the Lena Plains. Copyright © 2007 John Wiley & Sons, Ltd.     

渭河流域沉积矿物组合定量分析及示踪

扫描电镜定量分析沉积物矿物组合的方法,可以快速准确得到大量详细的矿物组合、矿物颗粒大小和岩屑组成等信息。尝试利用这一方法,研究渭河流域现代河流样品的矿物组合和沉积物碎屑组分,探究其在沉积物源示踪上的应用。研究表明,渭河流域现代沉积重矿物组合主要以角闪石、帘石类矿物和石榴石为主,不同区域沉积物矿物组合通过主成分分析图表（Principal Component Analysis,PCA）可以较好地区分开。轻矿物以石英和长石为主。碎屑组分石英—长石—岩屑（QFL）三角图解显示渭河干流和流经鄂尔多斯高原的两大主要支流北洛河和泾河的沉积物碎屑组分,主要位于再旋回造山带区域;而北秦岭山前河流沉积碎屑组分则主要位于岩浆岛弧区域。这一结果符合区域地质构造背景,表明扫描电镜定量分析手段可很好地应用于沉积物碎屑组分QFL三角图解、重矿物组合物源示踪研究。     

Textural and Geochemical Characteristics of Proglacial Sediments: A Case Study in the Foreland of the Nelson Ice Cap, Antarctica

This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sediments are characteristic of glacigenic deposits, but very different from those of aeolian and lacustrine sediments. Moreover, the grain size distributions of the proglacial sediments are fractal with a dimension of about 2.9, and the fractal dimensions can be used as another summary statistical parameter for quantifying the relative amounts of coarse and fine materials. Correlations between the absolute element abundances of the proglacial sediments are very weak due to mineral partitioning and other effects of glacial processes, but correlations between the element/Rb ratios are statistically significant. This finding indicates that element/Rb ratios can be used to reduce or eliminate the effects of glacial processes, evaluate geochemical data and determine the sediment provenance in the for     

利用锆石形态、成分组成及年龄分析进行沉积物源区示踪的综合研究

通过盆地碎屑沉积物分析示踪源区,进而探讨区域构造演化已成为当前地学研究的热点。盆地沉积物中的锆石不但分布广泛,而且稳定性极强,因而能保存大量的源区信息。随着锆石裂变径迹及U-Pb年龄谱分析等新测试技术的发展,锆石的形态、成分组成及年龄分析已成为盆地沉积物源区示踪的重要探针。本文结合实例,介绍了目前在综合利用锆石的形态、成分组成及年代学特征进行物源示踪的一些主要进展。由于物源示踪的复杂性,在利用锆石进行物源示踪时,应充分了解区域地质背景,密切结合其它物源示踪方法。     

Evolution of the Palaeotethys in the Eastern Mediterranean: a multi-method approach to unravel the age,provenance and tectonic setting of the Upper Palaeozoic Konya Complex and its Mesozoic cover sequence (south-central Turkey)

ABSTRACT

Siliciclastic sediments from the Upper Palaeozoic Konya Complex and its Mesozoic cover were studied by a multi-method approach combining thin-section petrography, bulk-rock geochemistry, mineral chemistry of rutile, and U–Pb geochronology of detrital zircons. Provenance sensitive data of samples from the Upper Palaeozoic Hal?c? Formation indicate sediment supply from mainly low- to medium-grade metamorphosed sedimentary rocks of felsic character, while the contribution from volcanic rocks was rare. The detrital zircon record of sediments from the Hal?c? Formation documents sediment supply from different sources and excludes a similar provenance. Some samples show great similarities with Palaeozoic sandstones from the cover sequence of the Saharan Metacraton and the Arabian–Nubian Shield, while the other samples indicate a provenance that must be sought in units with a southern Eurasian affinity. The upper limit for sediment deposition in the Hal?c? Formation is mostly constrained by Early Palaeozoic zircon populations; however, sediment accumulation in Pennsylvanian–Cisuralian time is more likely, contemporaneously with the Upper Palaeozoic succession on the Karaburun Peninsula (western Turkey). The provenance of sediments from the Upper Triassic Ard?çl? Formation remains enigmatic, but the source should be sought nonetheless in units close to the depositional site. In any case, detrital zircon age spectra and compositional data exclude recycling of underlying rock units (i.e. Hal?c? Formation). Overall, our new provenance data reveal great similarities between the Konya Complex and comparable units (Chios, Karaburun) but also highlight distinct differences in terms of sediment composition and provenance.     

Controls of heavy minerals and grain size in a holocene regressive barrier (Ilha Comprida,southeastern Brazil)

Ilha Comprida is a regressive barrier island located in southeastern Brazil that was formed essentially by Quaternary sandy sediments. Ilha Comprida sediments were analyzed to assess heavy mineral indices and grain size variables. The spatial variation of heavy minerals and grain size was interpreted in terms of the present barrier dynamics and the barrier’s evolution since the Middle Holocene. These analyses allowed for the identification of the main factors and processes that control the variation of heavy minerals and grain size on the barrier. Rutile and zircon (RZi) and tourmaline and hornblende (THi) are significantly sensitive to provenance and exhibit the contributions of the Ribeira de Iguape River sediments, which reach the coast next to the northeastern end of Ilha Comprida. In addition to the influence of provenance, TZi responds mainly to hydraulic sorting processes. This agrees with a sediment transport pattern characterized by a divergence of two resultant net alongshore drifts southwest of the barrier. The sediments from the Ribeira de Iguape River reach the barrier directly through the river mouth and indirectly after temporary storage in the inner shelf. The combination of grain size and heavy mineral analyses is a reliable method for determining sediment transport patterns and provenance.     

稀土配分模式在确定西天山风积物干扰粒级中的应用研究

系统研究了西天山地区水系沉积物在不同粒级的主要元素分布特征和风积黄土的粒级、元素含量分布特点。应用稀土配分模式的方法证实了水系沉积物中有风积黄土掺入。同时发现了风积黄土掺入对水系沉积物中元素含量产生了干扰作用,此种干扰作用随着采样粒级的变化而变化。通过对比,认为水系沉积物采样应该大于80目才能有效避免风积黄土的干扰,该研究为制定西天山地区水系沉积物测量的方法技术提供了重要依据。     

REE示踪沉积物物源研究进展

ＲＥＥ作为一种重要的沉积物物源示踪剂运用很广。在介绍了ＲＥＥ性质的基础上，对海水、河水、沉积岩、河流及边缘海沉积物中的ＲＥＥ元素丰度与配分模式特征进行了深入综述，概述了影响和控制ＲＥＥ丰度、模式及分馏特征的主要因素；论述了ＲＥＥ的物泊示踪意义以及在国内外应用情况与存在问题：源岩风化对ＲＥＥ分馏的影响；颗粒运及沉积时水动力分选对ＲＥＥ分馏可能造成的影响，即不同粒级中的ＲＥＥ不同的丰度与配分模式和碎屑     

长江沉积物源示踪研究进展

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