A CORER FOR SAMPLING SHALLOW-MARINE SANDS     

H. K. J. VAN DEN  BUSSCHE J. J. H. C. HOUBOLT 《Sedimentology》1964,3(2):155-159

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气体快速监测系统的组建及其在漠河冻土区天然气水合物钻探工程MK-2孔中的应用     

李松  刘晨  饶竹  赵省民  佟柏龄  邓坚  杨峰 《地质学报》2017,91(9):2131-2138

本文结合非动力型脱气器与动力型脱气器的优点,研制出一种适用于低流量、低流速等小型钻探工程的飞溅离心式钻井泥浆脱气设备,并组建一套陆域天然气水合物钻井气体的快速监测系统。此套系统中,钻井泥浆在脱气筒内自动采集气体并将气体样本通过导管引入实验室,通过阀切换、多柱分离、双检测器的气相色谱分析系统,可同时检测C_H__4、C_2H__6、C_2H_4、C_3H_8、C_3H_6、n-C_4H_(10)、i-C_4H_(10)、n-C_5H_(12)、i-C_5H_(12)、O_2、N_2、C_O2、CO等多种气体。其中,烃类气体的方法检出限为0.10~1.00μL/L,非烃气体的检出限为100μL/L~0.01%,方法精密度为1.65%~11.6%,样品分析周期约10min。该系统通过在黑龙江省漠河盆地开展的东北冻土区天然气水合物科学钻探工程MK-2孔的试运行,实现了钻井气体的在线快速监测,方法灵敏、稳定可靠,具有较好的精密度和较低的检出限,能够基本满足天然气水合物等气体钻探现场检测的需要。  相似文献   

甘肃黄土高原40a来土壤水分蒸散量变化特征   总被引：17，自引：4，他引：13  

姚小英  蒲金涌  王澄海  宋连春  邓振镛  冯建英  刘晓强 《冰川冻土》2007,29(1):126-130

用Penman公式计算了甘肃黄土高原20世纪60-90年代40 a来的潜在蒸散值,分析了潜在蒸散的时空变化特征并与蒸发皿所测值进行比较.结果表明:甘肃黄土高原潜在蒸散值的分布与纬度关系比较密切,随纬度的升高,潜在蒸散值增多,变化范围为1 600-2 200 mm·a^-1;潜在蒸散值受气温、降水的支配比较大,80年代最小,其次为70、60年代,90年代最大.60-90年代各地潜在蒸散值比实测值高30%-40%,其中夏、秋季潜在蒸散均大于蒸发器所测值,以夏季相差最大,达40%-100%;冬季则小于蒸发器所测值.潜在蒸散量与蒸发器所测值虽在数值上有所差别,但趋势基本一致,蒸发器所测值的峰值变化落后于理论计算值0.5月.90年代以来,各地土壤水分亏缺值增多,植被生长季节,作物水分利用都未及最适宜状态.  相似文献   

土壤及沉积物样品预处理的新技术--微波萃取法   总被引：8，自引：0，他引：8  

但德忠  罗方若  袁东  邓春林 《矿物岩石》2000,20(2):91-95

微波萃取是试样预处理的一种新技术,这一技术是对传统萃取方法的突破,是一项符合环境可持续发展的绿色技术。本文对这一技术的原理、特点、仪器及操作条件,特别是近十年来在土壤及沉积物样品预处理中的应用及进展进行评述。  相似文献   

中国大地构造单元划分   总被引：124，自引：18，他引：106       下载免费PDF全文

潘桂棠肖庆辉  陆松年邓晋福冯益民  张克信张智勇王方国  邢光福郝国杰 冯艳芳 《中国地质》2009,36(1):1-28

中国大地构造形成演化与大地构造分区研究已有百余年的历史,整体论述中国构造分区,都以不同学派对中国大陆地壳形成演化的不同认识论和方法论,有不同的方案.以黄汲清先生等多旋回构造观、王鸿祯先生等历史大地构造观和李春昱先生等板块构造观的"三大主流大地构造观"为指导思想的大地构造划分方案,是集中国地质构造之大成,在全国起指导作用,影响既广泛且深远.板块构造单元划分是当前板块构造细结构研究的关键问题.它既是板块构造研究的理论问题,也是区域地质研究和成矿预测评价亟待解决的实际问题.本文的大地构造分区图的编制是以地层划分和对比、沉积建造、火山岩建造、侵入岩浆活动、变质变形等地质记录为基础,承接融合中国"三大主流大地构造观"的经典划分理念,在板块构造-地球动力学理论指导下,以成矿规律和矿产能源预测的需求为基点,以不同规模相对稳定的古老陆块区和不同时期的造山系大地构造相环境时空结构分析为主线,以特定区域主构造事件形成的优势大地构造相的时空结构组成和存在状态为划分构造单元的基本原则,划分出中国的大地构造环境主要由陆块区和造山系组成为9个一级构造单元,以及相应的56个二级构造单元.中国大地构造研究还存在一系列重大科学问题,较准确地划分尚需很长时间的不懈努力.  相似文献   

攀西地区钾质煌斑岩岩石地球化学及源区构造环境分析          下载免费PDF全文

李再会  邓江红  肖渊甫  高媛 《地质找矿论丛》2005,20(2):80-86,136

分布于攀西及邻近地区的煌斑岩主要为云辉正煌岩-黑云正煌岩、白榴橄榄云辉岩、透辉云煌岩,常量元素特征表明岩石属于碱性系列、钾质钙碱性煌斑岩;过渡元素分配模式为幔源岩石的"W"型、不相容元素分配模式为大离子亲石元素和高场强元素富集的"驼峰"型、稀土元素分配模式为"右倾"的轻稀土富集型,表明该区煌斑岩为交代富集地幔部分熔融的产物.Ta-Nb-Ti负异常分配模式说明源区煌斑岩具有的交代富集地幔可能和板块俯冲有关.源区大地构造环境为活动大陆边缘的陆缘岛弧或陆缘火山弧区.  相似文献   

Emplacement of Deep Upper-Mantle Rocks into Cratonic Lithosphere by Convection and Diapiric Upwelling     

DRURY  M. R.; VAN ROERMUND  H. L. M.; CARSWELL  D. A.; DE SMET  J. H.; VAN DEN BERG  A. P.; VLAAR  N. J. 《Journal of Petrology》2001,42(1):131-140

Rocks containing breakdown products of majoritic garnet, derivedfrom the deep upper mantle, occur in kimberlite xenoliths andin orogenic peridotites from Otrøy in Norway. The Otrøyperidotites are banded harzburgites and dunites with similarcompositions to mantle xenoliths from Precambrian cratons andPhanerozoic supra-subduction-zone peridotites. Pressure–temperature(P–T) paths deduced for the Otrøy peridotites andkimberlite xenoliths from South Africa are consistent with emplacementof deep mantle peridotites into cratonic lithosphere by asthenospherediapirism. Numerical thermo-convection models provide insightinto the possible P–T histories of deep upper-mantle rocks.In the models, material from the base of the convecting systemis transported to depths of 60–100 km by convection andsmall (50–100 km) diapirs. Diapir intrusion induces small-scaleconvection in the low-viscosity deeper part of the thermochemicallydefined lithosphere. Small-scale convection in the craton rootcan produce complex P–T paths, complex recurrent meltinghistories and complex compositional structure in the craton.P–T paths derived from the numerical models for asthenospherediapirism in a hot upper mantle are consistent with the sequenceof sub-solidus P–T conditions deduced for the cratonicperidotites. KEY WORDS: asthenosphere diapirs; cratonic lithosphere; deep upper mantle; majoritic garnet  相似文献   

Significant change of extratropical natural variability and potential predictability associated with the El Niño/Southern Oscillation     

WILBUR Y. CHEN  HUUG M. VAN DEN DOOL 《地球，A辑:动力气象学与海洋学》1999,51(5):790-802

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Bedform migration and bed-load transport in some rivers and tidal environments     

JAN H. VAN DEN  BERG 《Sedimentology》1987,34(4):681-698

Reliable field data obtained by directly measuring bed-load transport of fine- to coarse-grained bed material are extremely scarce, mainly because of the difficulty of sampling accurately. Therefore, the verification of bed-load transport formulae is largely based on flume experiments, which refer to unrealistic shallow-water conditions. In this study, some bed-load transport formulae were tested against data from natural environments. As an alternative to ascertaining the bed-load transport rate by sampling the bed-load, the transport rate was deduced from data on bedform height and bedform celerity. For this purpose, 43 sets of data from rivers, representing a wide range of bed material, bedform dimensions and hydraulic conditions were collected as were some sets of data from tidal settings. Two formulae were used for the prediction of the bed-load transport: the formula of Van Rijn (1981) and the Kalinske (1947) formula as approximated by Elzerman & Frijlink (1951) (and, in the present study, slightly modified for application to tidal waters). Both the bed-load function of Van Rijn and the modified formula of Kalinske-Frijlink require data which are easily obtained and that can be measured accurately. At those stages of the flow when bed-load transport was high the Van Rijn function tended to overestimate that transport. For flow stages when bed-load transport was low the opposite was true. The modified Kalinske-Frijlink function gave consistently good results: 86% of the transport rates predicted using the river data were within 0·5–2·0 times the values actually measured.  相似文献   

Searching for analogues, how long must we wait?   总被引：2，自引：0，他引：2  

H. M. VAN DEN DOOL 《地球，A辑:动力气象学与海洋学》1994,46(3):314-324

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