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1.
常温下在pH4的HAc-NaAc缓冲体系中,Ga与1,5-二(2-羟基-5-磺基苯基)-3-氰基甲 (DSPCF)形成稳定的蓝色配合物。该配合物在波长630nm处有最大吸收,其表观摩尔吸光系数为3.8×10 ̄4L·mol ̄-1·cm ̄-1,配合比为n(Ga):n(DSPCF)=1:2,显色反应在20min内完成,稳定时间至少24h,Ga量在0~1.8mg/L时遵守比尔定律。采用TBP萃淋树脂分离干扰元素后可实现煤矸石中Ga的测定。  相似文献   

2.
裂变径迹定年法中国际标样的年龄测定   总被引:1,自引:0,他引:1  
翟鹏济  赵云龙 《铀矿地质》1995,11(4):240-243
第6届国际裂变径迹测定地质年代学术讨论会上推荐标准化刻度裂变径迹定年法,并推荐了几种定年标样。本文通过标准铀玻璃刻度系数定出值,利用外探测器法测定了国际标样中的3种桔石和两种磷灰石的年龄(FCT27.7±0.8Ma,BM16.1±0.5Ma,TR60.0±3.OMa,Durango30.8±1.9Ma),在误差范围内与参考年龄一致。  相似文献   

3.
陈义兵  胡霭琴 《地球化学》1999,28(6):515-520
采用颗粒级锆石U-Pb定年方法,精确测定了西天山前寒武纪天窗花岗片麻岩的结晶锆石年龄为798Ma,它代表了花岗质岩浆的结晶时代。花岗片麻岩具有较高的IAS值(1.17 ̄1.55)和LILE、LREE含量,明显的Eu负异常(δEu=0.24-0.38)和Ba、Sr、p、Ti、Nb、Ta的亏损,表明源岩为成熟度很高的陆壳物质。其负的εNd(t)值(-4.4 ̄-6.4)和较高的初始^87Sr/^86Sr  相似文献   

4.
对碘偶氮氯膦与铅显色反应及其应用   总被引:2,自引:0,他引:2  
杨敏思  王曙  陈刚莲 《岩矿测试》1995,14(4):292-294
研究了对碘偶氮氯膦(CPA-pI)与Pb ̄2+的显色反应。在pH5.8的(CH_2)_6N。-NO_3缓冲介质中,Pb ̄2+与CPA-pl形成1:2的蓝绿色配合物,在675nm处测定配合物的吸光度,其表现摩尔吸光系数为2.47×10 ̄4L.mol ̄-1·cm ̄-1Pb ̄2+浓度在0~1.16×10 ̄-5mol/L即0~2.4μml)符合比尔定律。试验了20余种共存离子的影响,经共沉淀结合巯基棉分离预处理试样溶液后,测定了硫精砂中微量Pb的含量。  相似文献   

5.
本文给出的滹沱群下亚群青石村组玄武岩Rb-Sr、Sm-Nd全岩等时线年龄为2045.8±17和2369±30Ma(Z),角门石40Ar-39Ar坪年龄和最高视年龄为1364±19和1932±19Ma(1);中亚群河边村组玄武岩Rb-Sr全岩等时线年龄图的投点呈完全离散状,Sm-Nd全岩等时线年龄为2322±31Ma(2),角门石40Ar-39Ar坪年龄和最高视年龄为1360和1742±17Ma(1)。根据上述Rb-Sr、Sm-Nd数据与已知青石村组、河边村组单颗粒锆石U-Pb法确定的成岩年龄2450±10和2400±20Ma(2)的明显差别,40Ar-39Ar均揭示为较典型受扰动的年龄谱和较发育的透人性构造、晚期岩脉等地质证据,认为Rb-Sr、Sm-Nd是重设的同位素体系。  相似文献   

6.
东秦岭陡岭群变质杂岩Sm-Nd、Rb-Sr、40Ar/39Ar、207Pb/206Pb年龄   总被引:11,自引:0,他引:11  
沈洁  张宗清  刘敦一 《地球学报》1997,18(3):248-254
本文用单颗粒锆石逐级蒸发207Pb/206Pb、SmNd、RbSr、40Ar/39Ar年代学方法对东秦岭陡岭群变质杂岩的形成时代、变质时期和构造归属进行了研究。结果表明:陡岭群变质杂岩形成于早元古代,年龄为2000Ma左右,在其形成后遭受了多期变质作用。片麻岩SmNd等时年龄1878±256Ma(εNd(t)=+2.8±2.6)代表了SmNd同位素系统重新发生均一化作用的时间。主期变质作用发生在833±17Ma(角闪石40Ar/39Ar高温坪年龄);另一期变质作用发生于422±16Ma(片麻岩Rb  相似文献   

7.
中国中、新生代板内变形速度研究   总被引:7,自引:0,他引:7  
依据中国中、新生代11803件岩浆岩常量元素化学全分析资料,采用Sugisaki的由岩石化学成分推算板块运动速度的方法,求得中国各构造时期板内缩短速度与扩张速度。印支、燕山与四川期板内平均缩短速度均在54~56cm/a,华北期稍小,为45cm/a,喜马拉雅期在中国西部平均缩短速度又达52cm/a,新构造期仅为25~28cm/a。在印支期—华北期,中国西南地区一直存在着扩张速度较低(02~16cm/a)的特提斯洋。喜马拉雅期以来中国西南部进一步碰撞,青藏高原隆升,地壳缩短;而东部地区则普遍表现为微弱的扩张(01~06cm/a)。  相似文献   

8.
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   

9.
研究结果表明,在混合表面活性剂CTMAB-吐温-60存在下的pH5.7~6.5的缓冲介质中,Sc(Ⅲ)与4,5-二溴苯基荧光酮(DBPF)形成高灵敏的多元配合物,其ε_(590)=2.26×10 ̄5L·mol ̄(-1)·cm ̄(-1),组成比为:Sc:DBPF:CTMAB=1:2:4。采用混合表面活性剂使增溶增敏作用更为显著,并加速了显色反应,增强了配合物的稳定性。而Na_2SO_4的加入能显著地提高体系的灵敏度。Sc量在0~0.36ug/ml范围内遵守比尔定律。方法可直接测定合成混合稀土中的Sc,回收率在98%~105%;结合沉淀分离和PMBP萃取分离,实现了地质试样中痕量Sc的测定。  相似文献   

10.
用氧同位素温度计测定了西阿尔卑斯DoraMaira地块含柯石英—镁铝榴石白片岩的峰期变质温度。石英(柯石英较变后)的δ ̄(18)O(8.1‰~8.6‰,n=6),多硅白云母的(6.2‰~6.4‰,n=3)、蓝晶石的(6.1‰,n=2)、石榴石的(5.5‰~5.8‰,n=9)、ellenbergerite的(6;3‰,n=1)和金红石的(3。3‰~3.6‰,n=3)δ ̄(18)O(SMOW)值反映了同位素平衡。以石英—石榴石—金红石分馏为基础测定的温度为700~750℃。以对压力敏感的反应:镁铝榴石+朽石英=蓝晶石十顽火辉石为依据确定的最小压力为3.1~3.2GPa。为了通过对温度敏感的脱水反应:滑石十蓝晶石=镁铝榴石十柯石英十水,来稳定镁铝榴石和柯石英,在700~750℃时,α(H_2O)必须减小到0.4~0。75。当镁铝榴石在x(CO_2)>0.02(T=750℃,P=3.0GPa)不稳定时,α(H_2O)的减少不会是由于CO_2的稀释所引起的。当缺乏较多的外来流体稀释剂(即CH_4或N_2时,就需要有熔体相)。在α(H_2O)=1.O时,花岗岩的固相线温度为680℃/3.0GPa,在α(H_2O)=0.  相似文献   

11.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

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14.
正1 Introduction Geological studies established on several sections in Lanping-Simao basin have shown that the salt-bearing strata of Mengyejing formation(Yunlong Fm.in Lanping basin)are constituted by an alternation of salt layers and interbedded facies.The latter consists mainly of mudstones,and mudstone-rich conglomerate.The mineralogy and geochemistry of salt-bearing beds and  相似文献   

15.
正On 22nd April 2014,with the approach of the 45th World Earth Day,China’s Ministry of Land and resources issued the status of China’s mineral resources in 2013.The first task of the prospecting breakthrough strategy action implemented in the last five years has been completed,and China’s security capacity for mineral resources has been significantly improved.In the  相似文献   

16.
正There are more than 700 salt lakes with area of more than 1km2 on the Qinghai-Tibet Plateau of China.In recent years,an oilfield brine was also found in the Nanyishan Section of Qaidam Basin in the Qinghai-Tibet  相似文献   

17.
正1 Introduction Physical and numerical models are constructed to investigate the evolution and mechanism of salt migration driven by tectonic processes.In recent years,we have designed and ran series of models to simulate salt  相似文献   

18.
正The study of Cretaceous-Palaeogene salt-bearing strata of the Khorat Basin Laos and the Lanping-Simao Basin in Yunnan,China has an great significance not only in explaining the basin evolution and the genesis of potash  相似文献   

19.
正Potash is one of the long-term scare deposits in China,and potash prospecting has long been listed as a key brainstorm project for our nation and geological prospecting units.There have been considerable studies in search for potash deposits in the Kuqa depression of the Tarim basin(Jackson et al.,1991;Gemmer et al.,2004;Vendeville,2005;Vendeville and Jackson,1992a,1992b),  相似文献   

20.
正1 Introduction Qaidam Basin in Qinghai,including 43 salt lakes with multiple dominant mineral such as potassium,magnesium,lithium etc.,is the most intensive distribution of Saline  相似文献   

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