{"title":"寒带风化石英颗粒表面结壳的形成--纳米尺度研究","authors":"","doi":"10.1016/j.sedgeo.2024.106715","DOIUrl":null,"url":null,"abstract":"<div><p>Sand-sized quartz grains selected from sediments of a Pleistocene inland dune (eastern Poland) were subjected to a series of laboratory analyses, including grain-size distribution, morphoscopy analysis, microtextural analysis using scanning electron microscope (SEM) and nanostructural analysis using transmission electron microscope (TEM). The results indicate the presence of a crust on the surface of all of the studied quartz grains and a surprisingly low number of aeolian-induced mechanical microtextures. The TEM examination identifies illite-smectite assemblages as the main component of the crust, accompanied by amorphous silica, local accumulation of Fe, K, Ca, Mg oxides, and mineral particles (quartz, K-feldspar, chlorite). The thickness of the crust reaches approx. 0.1–0.2 μm and varies from the minimum on micro-protrusions up to the maximum in micro-cavities. Here, we present a new theory on the origin of the crust observed on the surface of cold-climate aeolian quartz grains. We postulate that the crust is formed within a near-surface saltation layer during active aeolian transport of sand-sized grains and clay-sized particles operating under cold-climate conditions. The development of abrasion features and the formation of the crust are interpreted here to occur simultaneously and continuously during the aeolian transport. The formation of the crust results from specific properties of aeolian transport (i.e. self-induced electrification and electrification mechanisms of quartz grains) and the quartz grains themselves (i.e. grain shape and surface microtopography).</p></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":null,"pages":null},"PeriodicalIF":2.7000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Formation of the crust on the surface of cold-climate aeolian quartz grains – A nano-scale study\",\"authors\":\"\",\"doi\":\"10.1016/j.sedgeo.2024.106715\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Sand-sized quartz grains selected from sediments of a Pleistocene inland dune (eastern Poland) were subjected to a series of laboratory analyses, including grain-size distribution, morphoscopy analysis, microtextural analysis using scanning electron microscope (SEM) and nanostructural analysis using transmission electron microscope (TEM). The results indicate the presence of a crust on the surface of all of the studied quartz grains and a surprisingly low number of aeolian-induced mechanical microtextures. The TEM examination identifies illite-smectite assemblages as the main component of the crust, accompanied by amorphous silica, local accumulation of Fe, K, Ca, Mg oxides, and mineral particles (quartz, K-feldspar, chlorite). The thickness of the crust reaches approx. 0.1–0.2 μm and varies from the minimum on micro-protrusions up to the maximum in micro-cavities. Here, we present a new theory on the origin of the crust observed on the surface of cold-climate aeolian quartz grains. We postulate that the crust is formed within a near-surface saltation layer during active aeolian transport of sand-sized grains and clay-sized particles operating under cold-climate conditions. The development of abrasion features and the formation of the crust are interpreted here to occur simultaneously and continuously during the aeolian transport. The formation of the crust results from specific properties of aeolian transport (i.e. self-induced electrification and electrification mechanisms of quartz grains) and the quartz grains themselves (i.e. grain shape and surface microtopography).</p></div>\",\"PeriodicalId\":21575,\"journal\":{\"name\":\"Sedimentary Geology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2024-07-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Sedimentary Geology\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0037073824001386\",\"RegionNum\":2,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sedimentary Geology","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0037073824001386","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOLOGY","Score":null,"Total":0}
引用次数: 0
摘要
对从更新世内陆沙丘(波兰东部)沉积物中选取的沙粒大小的石英颗粒进行了一系列实验室分析,包括粒度分布、形态镜分析、使用扫描电子显微镜(SEM)进行的微纹理分析以及使用透射电子显微镜(TEM)进行的纳米结构分析。结果表明,所研究的所有石英颗粒表面都存在结壳,而且由风化引起的机械微纹理数量少得惊人。通过 TEM 检验发现,伊利石-直闪石集合体是结壳的主要成分,此外还有无定形二氧化硅、铁、钾、钙、镁氧化物的局部堆积以及矿物颗粒(石英、钾长石、绿泥石)。结壳厚度约为 0.1-0.2 μm,从微突起上的最小厚度到微腔中的最大厚度不等。在此,我们提出了关于在寒冷气候风化石英颗粒表面观察到的结壳起源的新理论。我们推测,在寒冷气候条件下,沙粒和粘土颗粒在风化迁移过程中,在近表面盐化层内形成结壳。这里的解释是,磨蚀特征的形成和结壳的形成是在风化搬运过程中同时持续发生的。结壳的形成源于风化搬运的特殊性质(即石英颗粒的自诱导电化和电化机制)和石英颗粒本身(即颗粒形状和表面微观形貌)。
Formation of the crust on the surface of cold-climate aeolian quartz grains – A nano-scale study
Sand-sized quartz grains selected from sediments of a Pleistocene inland dune (eastern Poland) were subjected to a series of laboratory analyses, including grain-size distribution, morphoscopy analysis, microtextural analysis using scanning electron microscope (SEM) and nanostructural analysis using transmission electron microscope (TEM). The results indicate the presence of a crust on the surface of all of the studied quartz grains and a surprisingly low number of aeolian-induced mechanical microtextures. The TEM examination identifies illite-smectite assemblages as the main component of the crust, accompanied by amorphous silica, local accumulation of Fe, K, Ca, Mg oxides, and mineral particles (quartz, K-feldspar, chlorite). The thickness of the crust reaches approx. 0.1–0.2 μm and varies from the minimum on micro-protrusions up to the maximum in micro-cavities. Here, we present a new theory on the origin of the crust observed on the surface of cold-climate aeolian quartz grains. We postulate that the crust is formed within a near-surface saltation layer during active aeolian transport of sand-sized grains and clay-sized particles operating under cold-climate conditions. The development of abrasion features and the formation of the crust are interpreted here to occur simultaneously and continuously during the aeolian transport. The formation of the crust results from specific properties of aeolian transport (i.e. self-induced electrification and electrification mechanisms of quartz grains) and the quartz grains themselves (i.e. grain shape and surface microtopography).
期刊介绍:
Sedimentary Geology is a journal that rapidly publishes high quality, original research and review papers that cover all aspects of sediments and sedimentary rocks at all spatial and temporal scales. Submitted papers must make a significant contribution to the field of study and must place the research in a broad context, so that it is of interest to the diverse, international readership of the journal. Papers that are largely descriptive in nature, of limited scope or local geographical significance, or based on limited data will not be considered for publication.