PAN－S光度法测定水和河泥中微量锰     

魏琴  杜斌  马荣 《矿物岩石》1994,(3)

本文研究了ＰＡＮ－Ｓ与锰的显色反应。配合物的最大吸收峰位于５３８ｎｍ波长处，表观摩尔吸光系数为２．９×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），锰量在０─１．６μｇ／ｍｌ范围内符合比尔定律，方法用于水和河泥中微量锰的测定，结果良好。  相似文献   

On reducing ambiguity in the interpretation of transient electromagnetic sounding data1     

M. Goldman  A. Du Plooy  M. Eckard 《Geophysical Prospecting》1994,42(1):3-25

An attempt to resolve non-uniqueness in the interpretation of transient electromagnetic (TEM) sounding data using measured data alone is made. It is shown in the various examples studied that sufficiently early time measurements can be the determining factor in reducing the ambiguity caused by model equivalence. The early delay times thus play a dual role in transient soundings: they are responsible for resolving shallow structures and they may eliminate the ambiguity in the interpretation of geoelectric parameters of deeper targets. This is illustrated by the results of a follow-up TEM survey at the Dead Sea coast of Israel where the use of supplementary early time measurements allowed non-uniqueness in the determination of the depth to fresh/saline groundwater interface to be resolved.  相似文献   

小莱河麻粒岩相铁建造的矿物组合—变质过程p、T变化的探讨     

黄婉康  王明再  龚国洪  杜春辉  王岩国 《矿物学报》1994,14(3):247-256,T001

小莱河太古宙麻粒岩相铁建造的矿物组合有：①斜方辉石（Fs87）＋钙铁辉石＋石英＋磁铁矿±莱河矿；②铁闪石＋铁浅闪石质角闪石＋石英＋磁铁矿＋碳酸盐±Fe－镁川石（云辉闪石）。辉石的出溶显示了它形成的不同阶段：片晶发育的OpxⅡ－CpxⅡ是最后稳定产物，计算的平衡温度是742℃，按相图获得的压力是7×108～7．8×108Pa；钙铁辉石中“001”片晶是易变辉石片晶转变的，Opx－Cpx－Pig（片晶）阶段据相图推测可能形成于近820℃，8×108Pa的条件下。原始均一相的OpxⅠ－CpxⅠ阶段矿物成分按估算的片晶含量计算，它们的形成温度接近820℃，可能的压力范围是11×108～13×108Pa。由此得到ITD型麻粒岩相p－T－t轨迹。莱河矿无氧化成因的证据，认为它是在麻粒岩相条件下生成的。云辉闪石的Si—O链重复周期是3×，其Fe／（Fe＋Mg）＝0．85，是接近富铁端元的Fe－镁川石，它与闪石一起在640到近700℃条件下交代了辉石。  相似文献   

江苏宜兴东岭逆冲断层带的构造地球化学特征研究     

杜定全 《矿物学报》1994,14(4):394-398

宜兴东岭逆冲断层带是一条脆性剪切带，断层带内不同变形程度的断层岩在构造地球化学特征上有明显的集散规律，随着岩石变形程度的增加，SiO2的含量相对降低，除FeO以外的其它主元素和除Li以外的微量元素则相对富集，即在断层岩变形过程中，SiO2自变形相对强烈的断层带中心向两侧的硅化带迁移，除FeO和Li之外的其它主元素和微量元素则自断层带两侧向中心迁移。这种迁移趋势是受各元素本身构造地球化学特性所制约。  相似文献   

淮北煤田早二叠世化石植物古生态     

杜美利 《中国煤田地质》1994,6(4):21-25

淮北煤田早二叠世化石植物丰富，其形成于炎热多雨的热带滨海三角洲沉积体系中。下三角洲平原是该区化石植物最宜生长的地方。早二叠世该区化石植物常形成四类植物群落：森林沼泽植物群落、沿岸水生植物群落、高地植物群落、三角洲平原真蕨及种子蕨混生植物群落（早期）、树蕨－大羽羊齿类雨林植物群落（晚期）。随着时间的推移，这四类植物群落的结构及面貌发生着不断的变化；其演替显示，早二叠世晚期该区气侯更加湿热，雨林气侯更为普遍。  相似文献   

南极长城站至莫斯科和伊尔库茨克路径上时延的测量与传播路径研究          下载免费PDF全文

孙宪儒  王聚杰  杜军虎  杨维富 《极地研究》1994,6(1):61-65

本文介绍了利用在南极长城站接收来自ＲＷＭ（莫斯科）和ＲＩＤ（伊尔库茨克）台的授时信号的无线电波时延的测量方法，并依据１９９１年４月至１９９１年９月所测量的传播时延数据分析了电波传播路径。说明了沿长、短大圆路径的传播时段。判定存在着非大圆路径传播并阐明了关于非大圆路径传播的一些变化规律。对非大圆路径发生的条件进行了探讨  相似文献   

Sedimentary Features of Shallow Ancient River Channels on the Northern Shelf of the South China Sea1     

Kou Yangqi  Du Deli 《《地质学报》英文版》1995,8(1):85-98

Abstract Quaternary buried ancient river channels are widespread in the shallow-level sediments of the northern shelf of the South China Sea. The sedimentary sequence mainly of fluvial deposits comprise an important component part of the low-stand system tract and transgressive system tract in the study region. The plannar variation and spatial association of the sedimentary features such as incised valley fillings, deltaic foreset wedges and block slides of shelf-marginal fans reflect the palaeogeographic environment during the fall of the regional sea level in the northern part of the South China Sea. Based on the high-resolution seismic reflection data and gelogical data from boreholes, the present paper makes an integrated interpretation of the Quaternary ancient river channels in the shallow sediments of the study area, studies the sedimentary features of the ancient channels such as their spatial distribution, seismic facies reflection indicators, sedimentary facies and sand-body types, and discusses their formational setting and evolutionary model, with the main purpose to render a service to the hydrocarbon resources exploration and development and marine engineering in the northern shelf of the South China Sea.  相似文献   

西秦岭岷县地区二叠纪裂陷带斜坡沉积及其构造意义   总被引：1，自引：0，他引：1  

王治平  陈素华 《现代地质》1995,9(3):300-310

秦岭造山带西段，二叠纪裂陷作用非常活跃。位于西秦岭中部的岷县红崖、梅州一带，二叠系以粉碎屑沉积为主，泥质较少。根据对其岩石类型、沉积构造、岩石组合和生物特征的分析，认为这套地层主要形成于海底扇体系的内扇和中扇环境，外扇不发育，系由碎屑流和浊流沉积组成，包括内扇的水道和水下天然堤沉积及中扇的网状水道和朵叶体沉积。这套地层沿中秦岭南缘呈ＮＷＷ－ＳＥＥ方向延伸，代表了二叠纪西秦岭裂谷的存在及其继续裂陷的活动特征。  相似文献   

A THREE-DIMENSIONAL RANDOM DISPERSION MODEL WITHIN SURFACE LAYER          下载免费PDF全文

Du Shuming  Wang Yanchang  Li Zongkai 《Acta Meteorologica Sinica》1990,4(2):213-220

Taking advantage of the relation of lateral Lagrangian time scale T_LY with the stability and height,we establish a three-dimensional random dispersion model and simulate the dispersing process of a ground source within the surface layer.The results calculated show that under the condition of stable stratification our model is obviously better improved than those obtained by assuming T_LY to be constant,while under unstable condition,not much improved.  相似文献   

Sensitivity analysis for the effects of meteorological and radioactive release conditions on radiation doses from nuclear power plant accidents     

Wei Du  Robert L. Goble 《GeoJournal》1990,21(3):273-282

This paper briefly reviews several large-scale modeling systems for nuclear power plant accidents in the United States, and summarizes our recent modeling results for the effects of key meteorological conditions, radioactive release characteristics, and evacuation strategies on radiation doses. This work was intended to be useful in the formulation of emergency plans for nuclear power plant accidents. The sensitivity analyses establish a scale for comparing impacts at various locations and over time depending on the variation of those key parameters, and have clear implications for emergency planning.  相似文献