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161.
This paper is intended to be a constructive discussion of Fiket et al. (2017, Geostandards and Geoanalytical Research , 41 , 123–135), who dealt with the determination of major, trace and rare earth elements in several sediment and soil certified reference materials. In the present author's view, the paper by Fiket et al. (2017) suffers from a lack of reference to several publications in which somewhat similar results had already been reported. The present contribution therefore provides a comparison of previously published results with those of Fiket et al. for the CRMs soil NCS DC 77302 (GBW 07410), stream sediment NCS DC 73309 (GBW 07311), marine sediments MESS‐3 and NCS DC 75301 (GBW 07314) and estuarine sediment IAEA‐405. It is argued that this fuller consideration (a) allows critical evaluation of the quality of the results presented by Fiket et al. and (b) highlights the advantages of their work. Finally, attention is drawn to the (possible or real) problems that can arise during simultaneous determination of multiple trace elements.  相似文献   
162.
The wetting deformation of coarse granular materials is often considered to be an important cause of the core wall rockfill dam cracks during impounding. By analyzing existing research results, this paper proposes a hyperbolic relationship between the wetting axial strain and wetting stress level and puts forwards a warped surface relationship among spherical stress, shear stress, and the ratio of wetting volumetric strain to wetting axial strain. To illustrate its practicability, the wetting strain model's parameter determination process is introduced and the rockfill materials wetting parameters are determined using the triaxial wetting test data. Moreover, the collapse settlement of Guanyinyan rockfill dam during first impounding is numerically simulated using the proposed method to calculate rockfill wetting deformation and verified by field measurements and monitoring data. The results show that the calculative method of wetting deformation proposed in this paper is reasonable and practical; the wetting deformation of upstream rockfill materials would cause an adverse deformation trend, which may lead to crack occurrence at the upstream slope and dam crest; and the Guanyinyan rockfill dam cracks on the top of junction mainly caused by the wetting deformation of upstream rockfill.  相似文献   
163.
韩光中 《地理科学》2016,36(8):1277-1284
对南方丘陵区3种不同母质水稻土时间序列黏粒矿物的X-射线衍射(XRD)进行分析发现:紫色砂页岩(PS)母质起源土壤的黏粒矿物以高岭石类似矿物为主;第四纪红黏土(RC)母质起源土壤的黏粒矿物以高岭石类似矿物、伊利石类似矿物与三羟铝石为主;红砂岩(RS)母质起源土壤的黏粒矿物以1.4 nm过渡矿物、高岭石类似矿物与三羟铝石为主。 这3种母质土壤种稻后黏粒矿物的变化大体可分为2种情况。RC与RS母质的起源土壤种稻后,土壤黏粒矿物的变化相对较小,伊利石类似矿物相对含量有所增加,这可能主要与钾肥的持续施用有关。PS母质的起源土壤种稻后,土壤黏粒矿物变化相对较大,表现为高岭石类似矿物相对含量降低,低结晶度的伊利石或次生绿泥石与三羟铝石相对含量上升。PS母质发育的土壤种稻后脱钾明显且主要集中在原生矿物部分。这种原生矿物的脱钾作用对土壤黏粒含量和黏粒矿物的类型都有较大影响。 起源土壤的黏粒矿物通常会被水稻土所继承,并在水稻土发育过程中相对稳定,可以用其来指示起源土壤(或母质)的物源组分。  相似文献   
164.
吴跃兴  蔡云开 《现代地质》1995,9(4):509-515
摘要:用热解色谱(Rock-Eval)对2个褐煤样、3个气煤样的28个分离组分进行了研究,揭示了不同密度镜质组组分之间生烃潜力具有较大的差异性;镜质组不仅可以作为重要的生气母质,而且还可以作为重要的生油母质。  相似文献   
165.
聚能爆破在石材切割应用中的试验研究   总被引:1,自引:0,他引:1  
季荣生 《现代地质》1998,12(1):138-142
摘 要 简单分析了聚能爆破装药在孔内爆破的力学效应‚阐明了聚能爆破对岩石定向破裂 的控制机理。在聚能爆破切割石材过程中‚聚能射流起到前期切割出定向裂缝的作用‚石材 的最终开裂由后期爆破产生的气体的准静态胀楔作用来完成。通过提高炸药爆速、增大装药 密度等方法可以提高聚能装药爆炸后形成射流的能量和改善聚能爆破切割石材的效果。  相似文献   
166.
材料研究与制备过程中的几个矿物学岩石学问题   总被引:4,自引:0,他引:4  
在材料的研究与制备过程中往往会遇到很多有趣的矿物学、岩石学问题。这些问题有些是矿物学工作者和材料研究者所熟悉的,是材料研究者直接利用了矿物学工作者的研究成果。而有些问题是材料研究者首先发现,并将其中的某些条件加以利用,但缺少深入的矿物学理论研究;还有些工作是矿物学工作者得到的矿物学纯理论研究成果,但却不知如何应用到材料的开发与研究中。这就造成了介于矿物学与材料学之间的一个薄弱环节。这个薄弱环节为矿物、岩石工作者提供了一个广阔的研究领域和很多富有诱惑力的崭新的研究课题。于是一个新的分支学科———矿…  相似文献   
167.
We have developed a rapid and accurate method to determine Zr, Nb, Hf and Ta (denoted as HFSE) in geological samples by inductively coupled plasma-mass spectrometry fitted with a flow injection system (FI-ICP-MS). The method involves sample decomposition by HF followed by HF dissolution of HFSE coprecipitated with insoluble M and Ca fluoride residues formed during the initial HF attack. This HF solution was directly nebulized into an ICP mass spectrometer. An external calibration curve method and an isotope dilution method (ID) were applied for the determination of Nb and Ta, and of Zr and Hf, respectively. Recovery yields of HFSE were > 96% for peridotite, basalt and andesite compositions, apart from Zr and Hf for peridotite (> 85%). No matrix effects for either signal intensities of HFSE or isotope ratios of Zr and Hf were observed in basalt, andesite and peridotite solutions down to a dilution factor of 100. Detection limits in silicate rocks were 40, 2, 1 and 0.1 ng g-1 for Zr, Nb, Hf and Ta, respectively. This technique required only 0.1 ml of sample solution, and thus is suitable for analysing small and/or precious samples such as meteorites, mantle peridotites and their mineral separates. We also present newly determined data for the Zr, Nb, Hf and Ta concentrations in USGS silicate reference materials DTS-1, PCC-1, BCR-1, BHVO-1 and AGV-1, GSJ reference materials JB-1, -2, -3, JA-1, -2 and -3, and the Smithsonian reference Allende powder.  相似文献   
168.
The Campi Flegrei caldera (Italy) has been the site of intense seismic activity over the past decades. This area is densely populated and includes important towns such as Napoli with historical sites and supporting many industries. For the proper use and management of the region, the evaluation of the dynamic properties of near-surface rocks is necessary.

The volcanological pattern has been reconstructed from the lithostratigraphies of several drillings. The most interesting and widespread pyroclastic products are the pozzolana deposit (soil) and the Neapolitan Yellow Tuff (rock). Both pozzolana and tuff products are covered by recent eluvial and coastal sandy deposits and younger volcanic products (<12 000 years). The characteristic ranges of the shear wave velocity (Vs) of the Campi Flegrei–Neapolitan soils and tuffs are defined and the primary influencing factors are evaluated. For the sandy deposits, the results show that eluvial and lacustral products have lower shear wave velocities than coastal products. For the volcanic products younger than 12 000 years b.p. the influence of vertical pressure is emphasized. As regards the pozzolana deposit (soil) and the Neapolitan Yellow Tuff (rock), a major influencing factor is shown by the textural characteristics and the different hardening degrees as a consequence of the diagenetic processes. The scattering of the Vs velocities for the same formation is so wide that only the variability ranges can be individuated. These results suggest a need to carry out detailed Vs measurements or, at least, to make a parametric study of the effect of the Vs ranges on seismic response analysis in order to give safe building codes.  相似文献   

169.
在模拟地壳的温度和压力条件下,测定了华北地台太行-五台和阴山地块的主要变质岩群和侵入岩共54个岩石样品的纵波速度(vp).各类岩石的vp在约4~10km深度内上升很快,在10~25km内继续增大,但是幅度变小,在该深度范围内达到了vp最大值;在30~35km之后到50km深度内的vp都趋于恒定.综合对比地壳的波速结构和岩石的波速特征表明,在太行-五台地块,五台群、滹沱群和古老花岗岩岩类构成上地壳,阜平群和恒山群构成中地壳,集宁群代表了下地壳的岩石组成;在阴山地块,马家店群、二道凹群、色尔腾山群和古老侵入岩类是中地壳和上地壳的组成部分,乌拉山群岩石则是下地壳的代表  相似文献   
170.
罗布泊罗北凹地第四系上部盐层中蕴藏丰富的卤水,卤水中则富含钾(KCl平均品位为1.40%)。文章通过对罗布泊卤水氢、氧、锶及硫同位素等分析及与塔里木盆地(河流)、柴达木盆地等地区对比研究,确定了罗布泊富钾卤水源于地表水,可能主要是塔里木盆地南北缘河流水;卤水中的硫钾等物质组分主要来源于南天山、塔里木盆地西北、西南部中新生代石膏钙芒硝石盐矿床或地层及其古代地层卤水。由于第四纪期间塔里木盆地西部抬升。  相似文献   
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