Lithostratigraphic position and petrographic characteristics of R.A.T. (“Roches Argilo-Talqueuses”) Subgroup, Neoproterozoic Katangan Belt (Congo)     

J.L.H. Cailteux  A.B.H. Kampunzu  M.J. Batumike 《Journal of African Earth Sciences》2005,42(1-5):82

The Neoproterozoic Katangan R.A.T. (“Roches Argilo-Talqueuses”) Subgroup is a sedimentary sequence composed of red massive to irregularly bedded terrigenous-dolomitic rocks occurring at the base of the Katangan succession in Congo. Red R.A.T. is rarely exposed in a continuous section because it was affected by a major layer-parallel décollement during the Lufilian thrusting. However, in a number of thrust sheets, Red R.A.T. is in conformable sedimentary contact with Grey R.A.T which forms the base of the Mines Subgroup. Apart from the colour difference reflecting distinct depositional redox conditions, lithological, petrographical and geochemical features of Red and Grey R.A.T. are similar. A continuous sedimentary transition between these two lithological units is shown by the occurrence of variegated to yellowish R.A.T. The D. Strat. “Dolomies Stratifiées” formation of the Mines Subgroup conformably overlies the Grey R.A.T. In addition, a transitional gradation between Grey R.A.T. and D. Strat. occurs in most Cu–Co mines in Katanga and is marked by interbedding of Grey R.A.T.-type and D. Strat.-type layers or by a progressive petrographic and lithologic transition from R.A.T. to D. Strat. Thus, there is an unquestionable sedimentary transition between Grey R.A.T. and D. Strat. and between Grey R.A.T. and Red R.A.T.The R.A.T. Subgroup stratigraphically underlies the Mines Subgroup and therefore R.A.T. cannot be comprised of syn-orogenic sediments deposited upon the Kundelungu (formerly “Upper Kundelungu”) Group as suggested by Wendorff (2000). As a consequence, the Grey R.A.T. Cu–Co mineralisation definitely is part of the Mines Subgroup Lower Orebody, and does not represent a distinct generation of stratiform Cu–Co sulphide mineralisation younger than the Roan orebodies.  相似文献   

基于"3S"技术的于田绿洲湿地动态变化研究   总被引：7，自引：4，他引：7  

刘玉安  塔西甫拉提·特依拜  沈涛  张玉虎 《中国沙漠》2005,25(5):706-710

以极端干旱区典型绿洲———于田绿洲为研究区,采用遥感(RS)、地理信息系统(GIS)和全球定位系统(GPS)相结合的方法,进行了湿地资源调查,查明了于田绿洲湿地类型、区域分布及面积,应用模型和分形理论,探讨了于田绿洲湿地的动态变化特征,并分析了其发生动态变化的原因。研究结果对于干旱区绿洲湿地的合理开发和可持续发展有着重要现实意义。  相似文献   

273.15K下LiCl-Li2B4O7-H2O体系热力学性质的等压研究   总被引：2，自引：0，他引：2       下载免费PDF全文

杨吉民  姚燕  张爱云  宋彭生 《盐湖研究》2005,13(1):19-24

用等压法研究了273 15K下LiCl-Li2B4O7-H2O体系中纯盐水溶液(离子强度范围为LiCl0 2046～2 5055mol·kg-1,Li2B4O70 1295～0 3700mol·kg-1)以及混合盐水溶液(离子强度范围为0 0931～2 4911mol·kg-1)渗透系数和水活度;计算了LiCl-Li2B4O7-H2O体系的饱和蒸汽压,获得饱和蒸汽压、渗透系数随离子强度的变化规律。用实验数据以最小二乘法求取了LiCl和Li2B4O7纯盐参数及体系的混合盐参数,拟合的标准偏差分别为0 0077和0 026。用该模型计算的渗透系数值与实验结果取得合理的一致。同时研究结果与273 15K下LiCl-Li2SO4-H2O体系的渗透系数随离子强度变化的规律作了比较。本研究对完善低温下含锂、硼盐湖卤水体系的热力学模型和盐湖资源的综合开发利用具有重要意义。  相似文献   

TRMM卫星降水数据在小尺度流域的评估与应用          下载免费PDF全文

周萌  江善虎  任立良 《水文》2016,36(1):22-26

选取史灌河流域上游黄泥庄站以上集水区域为研究流域,以地面站点观测为基准数据,评估TRMM 3B42V7版本卫星降水数据的精度,并采用上述两种降水数据驱动栅格型新安江模型,模拟黄泥庄站日径流和月径流过程。结果表明:2001~2010年TRMM 3B42V7降水数据与雨量站数据累积量的偏差不大,仅为1.71%,但相关系数较低,采用TRMM降水数据模拟的日径流能基本再现黄泥庄站的日径流过程,但对洪峰的模拟精度较低;TRMM月降水数据精度较高,相关系数为0.96,能够较为精确地模拟黄泥庄站的月径流过程。  相似文献   

乌兰哈达变质岩地层地热勘探井钻头选择与取心工艺          下载免费PDF全文

宋国龙  董劲松  李进安 《探矿工程》2016,43(12):41-44

内蒙古自治区察右后旗乌兰哈达苏木地热勘探井井深2006.87 m。采用石油30型钻机施工,钻遇地层大部分为变质岩,达1500 m以上,对牙轮钻头损坏严重,同时施工要求进行18次岩心采取。经过对钻头的试用、选择,最后选用HJ637G型牙轮钻头,钻进时效可达0.8～1.2 m,使用寿命可达到80～100 h。取心段采用川7-4型双管单动取心筒配合金刚石钻头,岩心采取率可达70%～95%。  相似文献   

永定河中下游MIS7以来地层沉积演化及新石器时代以来气候变化          下载免费PDF全文

赵勇  杨誉博  李瑞杰  杨吉龙  王强  李亚林  王纯君  魏波  方同明  王志辉 《中国地质》2021,48(4):1188-1199

利用廊坊东A27钻孔岩心资料,样品微体生物、孢粉特征综合分析,结合AMS14C测年,对永定河中下游地区MIS7以来的地层进行分析,建立了MIS7以来的沉积地层格架,并对其进行了年代厘定,讨论了该地区大约MIS7阶段以来氧同位素分期气候下的地层及环境效应。结果表明,永定河中下游地区晚第四纪可划分为U1～U8共8个沉积单元,分别对应于MIS1～MIS7以及MIS8晚期的沉积地层,与海洋氧同位素分期有很好的对应关系。U1单元为MIS1形成的湖沼—河谷—泛滥平原沉积,U2单元为MIS2形成硬质黏土(第1硬土层)—下切河谷—湖沼沉积,U3单元为MIS3形成的湖沼—河谷—泛滥平原沉积,U4单元为MIS4形成的河间地块沉积(第2硬土层,暴露失水沉积),U5单元为MIS5形成的湖沼夹分支河道沉积,U6单元为MIS6形成的下切河谷夹短暂湖沼沉积,U7单元为MIS7形成的以湖沼为主沉积,U8单元为MIS8晚期形成的泛滥平原沉积,重塑了MIS7以来沉积环境模式,建立了本区晚第四纪精细年代地层框架。笔者认为永定河中下游在新石器时期以河湖共存为主,在其晚期为湖沼发育达到顶峰,出现泥炭层,直至商周时期后在气候变化影响下湖沼消退转变为泛滥平原面貌,为区域古地理环境及生态修复提供重要参考依据。  相似文献   

混合表面活性剂存在下镓与O—Cl—PF显色反应的研究     

杨定国 《岩矿测试》1990,9(3):187-189

本文研究了在pH 6.5-7.8的(CH_2)_6N_4-HCl缓冲介质中,CDMAA和TritonX-100对Ga与o-Cl-PF和F~-显色反应的增敏作用。结果表明,Ga-o-Cl-PF-F-CDMAA-TritonX-100多元配合物λ_(max)为565nm,表观摩尔吸光系数ε=1.74×10~5L·mol~(-1)·Cm~(-1),Ga含量在0～6.0μg/25ml范围内符合比尔定律,用合成样和标样进行本方法考验,结果满意。  相似文献   

Nitrogen and sulfur species in Antarctic aerosols at Mawson,Palmer Station,and Marsh (King George Island)   总被引：4，自引：0，他引：4  

D. L. Savoie  J. M. Prospero  R. J. Larsen  F. Huang  M. A. Izaguirre  T. Huang  T. H. Snowdon  L. Custals  C. G. Sanderson 《Journal of Atmospheric Chemistry》1993,17(2):95-122

High volume bulk aerosol samples were collected continuously at three Antarctic sites: Mawson (67.60° S, 62.50° E) from 20 February 1987 to 6 January 1992; Palmer Station (64.77° S, 64.06° W) from 3 April 1990 to 15 June 1991; and Marsh (62.18° S, 58.30° W) from 28 March 1990, to 1 May 1991. All samples were analyzed for Na⁺, SO ₄ ^2– , NO ₃ ^– , methanesulfonate (MSA), NH ₄ ⁺ ,²¹⁰Pb, and⁷Be. At Mawson for which we have a multiple year data set, the annual mean concentration of each species sometimes vary significantly from one year to the next: Na⁺, 68–151 ng m^–3; NO ₃ ^– , 25–30 ng m^–3; nss SO ₄ ^2– , 81–97 ng m^–3; MSA, 19–28 ng m^–3; NH ₄ ⁺ , 16–21 ng m^–3;²¹⁰Pb, 0.75–0.86 fCi m^–3. Results from multiple variable regression of non-sea-salt (nss) SO ₄ ^2– with MSA and NO ₃ ^– as the independent variables indicates that, at Mawson, the nss SO ₄ ^2– /MSA ratio resulting from the oxidation of dimethylsulfide (DMS) is 2.80±0.13, about 13% lower than our earlier estimate (3.22) that was based on 2.5 years of data. A similar analysis indicates that the ratio at Palmer is about 40% lower, 1.71±0.10, and more comparable to previous results over the southern oceans. These results when combined with previously published data suggest that the differences in the ratio may reflect a more rapid loss of MSA relative to nss SO ₄ ^2– during transport over Antarctica from the oceanic source region. The mean²¹⁰Pb concentrations at Palmer and Marsh and the mean NO ₃ ^– concentration at Palmer are about a factor of two lower than those at Mawson. The²¹⁰Pb distributions are consistent with a²¹⁰Pb minimum in the marine boundary layer in the region of 40°–60° S. These features and the similar seasonalities of NO ₃ ^– and²¹⁰Pb at Mawson support the conclusion that the primary source regions for NO ₃ ^– are continental. In contrast, the mean concentrations of MSA, nss SO ₄ ^2– , and NH ₄ ⁺ at Palmer are all higher than those at Mawson: MSA by a factor of 2; nss SO ₄ ^2– by 10%; and NH ₄ ⁺ by more than 50%. However, the factor differences exhibit substantial seasonal variability; the largest differences generally occur during the austral summer when the concentrations of most of the species are highest. NH ₄ ⁺ /(nss SO ₄ ^2– +MSA) equivalent ratios indicate that NH₃ neutralizes about 60% of the sulfur acids during December at both Mawson and Palmer, but only about 30% at Mawson during February and March.  相似文献   

钛-氨三乙酸-对氯苯基荧光酮-CTMAB四元配合物的分光光度法研究     

王东进  谢增鸿  樊祺泉  蔡文进  黄炳俊  张振欣 《岩矿测试》1990,(2)

本文研究Ti(Ⅳ)-氨三乙酸(NTA)-对氯苯基荧光酮(p-ClPF)-CTMAB四元配合物的显色条件。结果表明,在pH5.8—6.6形成了摩尔比为Ti(Ⅳ):NTA:p-ClPF:CTMAB=1:1:3:3的四元配合物,借此反应测定钛,灵敏度高,其ε_(573nm)=2.1×10~5L·mol~(-1)·cm~(-1)。Ti(Ⅳ)浓度在0—1.4μg/10ml范围服从比耳定律。已用本法直接测定了岩矿和铝合金中的Ti,结果满意。  相似文献   

山东角07井注(漏)水诱发地震——地表宏观现象与震群活动特点          下载免费PDF全文

卢守安  苏鸾声  陈正品  陈宝银  邹泉生 《地震地质》1987,9(3):84

本文介绍了1985年底发生在山东胜利油田角07井的一次注水诱发型小震群的活动情况,论述了地表宏观现象,分析与讨论了这次诱发型震群的活动特点  相似文献