48 resultados para Liebenberg, Frederik Ludvig, 1810-1894.


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Through the detailed analyses of Mesozoic tectono-stratigraphy and basin formation dynamic mechanism and the styles of different units in the western margin of Ordos Basin(Abbreviated to "the western margin"), while some issues of the pre-Mesozoic in the western margin and central part of Ordos Basin also be discussed, the main views and conclusion as follows: 1. There are three types of depositional systems which are related with syndepositional tectonic actions and different tectonic prototype basins, including: alluvial fan systems, river system (braided river system and sinuosity river system), lacustrine-river delta system and fan delta system. They have complex constitutions of genetic facies. For the tectonic sequence VI, the fan sediments finning upper in the north-western margin and coarse upper in the south-western margin respectively. 2. In order to light the relationship between basin basement subsidence rate and sediment supply and the superposed styles, five categories of depositional systems tracts in different prototype basins were defined: aggrading and transgressive systems tracts during early subsidence stage, regressive and aggrading systems tracts during rapid subsidence, upper transgessive systems tracts during later subsidence stage. Different filling characteristics and related tectonic actions in different stages in Mesozoic period were discussed. 3. In order to determined the tectonic events of the provenance zones and provenance strata corresponding to basins sediments, according the clastics dispersal style and chemical analyses results of sediments in different areas, the provenance characteristics have been described. The collision stage between the "Mongolia block" and the north-China block may be the late permian; The sediments of Mesozoic strata in the north-western margin is mainly from the Alex blocks and north-Qilian Paleozoic orogeny, while the south-western margin from Qinling orogeny. The volcanic debris in the Yan'an Formation may be from the arc of the north margin of north-China block, although more study needed for the origin of the debris. The provenance of the Cretaceous may be from the early orogeny and the metamorphic basement of Longshan group. 4. The subsidence curve and subsidence rate and sedimentary rate in different units have been analyzed. For different prototype basin, the form of the subsidence curves are different. The subsidence of the basins are related with the orogeny of the basins.The beginning age of the foreland basin may be the middle Triassic. The change of basement subsidence show the migration of the foredeep and forebulge into the basin. The present appearance of the Ordos basin may be formed at the late stage of Cretaceous, not formed at the late Jurassic. 5. The structure mode of the west margin is very complex. Structure transfer in different fold-thrust units has been divided into three types: transfer faults, transition structures and intersected form. The theoretic explanations also have been given for the origin and the forming mechanism. The unique structure form of Hengshanpu is vergent west different from the east vergence of most thrust faults, the mechanism of which has been explained. 6. In Triassic period, the He1anshan basin is extensional basin while the Hengshanbu is "forland", and the possible mechanism of the seemingly incompatible structures has been explained. First time, the thesis integrate the Jurassic—early Cretaceous basins of west margin with the Hexi corridor basins and explain the unitive forming mechanism. The model thinks the lateral extrusion is the main mechanism of the Hexi corridor and west margin basins, meanwhile, the deep elements and basement characters of the basins. Also, for the first time, we determine the age of the basalt in Helanshan area as the Cretaceous period, the age matching with the forming of the Cretaceous basins and as the main factor of the coal metamorphism in the Helanshan area. 7. The Neoprotterozoic aulacogen is not the continuation of the Mesozoic aulacogen, while it is another new rift stage. In the Paleozoic, the Liupanshan—southern Helanshan area is part of the back-arc basins of north Qilian ocean. 8. The Helanshan "alacogen" is connected with the north margin of north China block, not end at the north of Zhouzishan area like "appendices". Also, I think the upper Devonian basin as the beginning stage of the extensional early Carboniferous basins, not as a part of the foreland basins of Silurian period, not the collision rift. 9. The controlling factor of the difference of the deformation styles of the north-west margin and the south-west margin is the difference of the basements and adjacent tectonic units of the two parts.

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白牛厂矿床是超大型银多金属矿床,除银储量(>7000t)达到超大型规模外,铅、锌、锡储量均达大型规模,同时伴生大量的分散元素(In、Cd、Ge、Ga等)。矿床位于滇东南个旧和都龙矿田之间,赋存于华南加里东褶皱系滇东南褶皱带西北缘的中寒武统细碎屑岩系之中,北西面以弥勒断裂与扬子地块分界,南西以红河断裂为界与哀牢山断块毗邻,南连越北古陆,东部文麻断裂与南岭褶皱系连为一体,区内地质构造、岩浆活动和矿化作用均较复杂,各构造单元的构造演化对白牛厂银多金属矿床均有不同程度的影响。 白牛厂银多金属矿床自80年代后期被发现以来,已有多家单位和个人在该区开展了一系列的研究工作。但是,在成矿物质及流体来源、矿床成因、矿床与花岗岩的关系等方面都存在诸多争议。本文在深入细致的野外地质工作基础上,对矿石进行了系统的显微镜鉴定,并对部分矿物做了电子探针定量及面扫描分析,详细研究了矿床成矿元素特征及主量元素、微量元素、稀土元素、同位素地球化学特征,主要取得以下结论性成果: 1. 银矿物的赋存状态及形成阶段。银主要以硫盐或复硫盐矿物的形式出现,方铅矿是主要的载银矿物。原生银矿物明显分为两组:一组为Ag的黝铜族矿物和Ag的锑硫盐矿物,产于方铅矿的内部或与方铅矿连生形成文象状连晶,与方铅矿具有相似的物源,属热水沉积成因;另一组为Ag的锡硫盐矿物,产于方铅矿边部,往往伴随锡石、黄锡矿、辉锑锡铅矿产出,可见黄锡矿交代锡石形成镶边结构,暗示了其岩浆热液成因。 2. 花岗岩特征及其与成矿的关系。白牛厂矿区花岗岩具有富硅、富碱及高钾低钠特点,属铝过饱和钙碱性岩,与花南改造型花岗岩相似,属同碰撞S型花岗岩,成岩物源主要是基底变质岩重熔作用形成的花岗岩浆,Ag、Pb、Zn、Sn等成矿元素含量较高;与矿石稀土元素对比研究表明,花岗岩稀土配分模式与矿区东南部穿心洞、对门山和阿尾矿段矿石相似,而与矿区西北部白羊矿段矿石相差较大,暗示后期岩浆叠加改造作用主要发生在矿区东南部诸矿段。   3. 矿床含矿沉积建造地球化学特征。通过与中国大厂、个旧典型热水沉积硅质岩,加拿大沙利文矿山的条带状富电气石热液沉积岩和加拿大Agnico-Eugle矿山的铁建造中的条带状燧石岩以及现代海底热水沉积物对应的主量元素、微量元素及稀土元素对比研究,为白牛厂矿床含矿沉积建造提供了热水沉积成因的地球化学证据,指出该区中寒武世可能发生了广泛的热水沉积事件。   4. 成矿物质及成矿流体来源。系统的铅、硫同位素研究表明,中寒武世热水沉积成矿期金属成矿元素及硫主要是由下地壳古老变质岩淋滤出来的;燕山期花岗岩也在矿区东南部叠加改造较强的部位提供了Sn等部分金属成矿元素及硫。碳、氧同位素及矿石稀土元素反映矿床早期成矿流体源于深部岩浆,晚期主要来源于燕山期花岗岩浆。   5. 矿床分散元素特征。分散元素In、Cd、Ga含量较高,平均含量分别为33.21×10-6、389.8×10-6、10.18×10-6,初步估计该矿床In、Cd、Ga储量分别大于180t、20000t、600t,闪锌矿是分散元素In、Cd、Ga主要的载体矿物。 6. 可能的矿床成因模式。白牛厂银多金属矿床是长期以来多种地质作用综合的产物,具有多来源、多期次成矿特点,经历了广泛且具有重要成矿意义的中寒世热水沉积成矿作用和燕山晚期岩浆热液叠加改造作用,热水沉积成矿作用形成了层状、似层状矿体,燕山期岩浆热液在矿区东南部对矿床强烈叠加改造,白牛厂银多金属矿床应属“热水沉积+岩浆热液叠加改造”成因。

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The interaction between drugs and human serum albumin (HSA) was investigated by capillary electrophoresis (CE). It involves stereoselectivity, drug displacement and synergism effects. Under protein-drug binding equilibrium, the unbound concentrations of drug enantiomers were measured by frontal analysis (FA). The stereoselectivity of verapamil (VER) binding to HSA was proved by the different free fractions of two enantiomers. In physiological pH (7.4, ionic strength 0.17 phosphate buffer) when 300 mu M (+/-) VER were equilibrated with 500 mu M HSA, the concentration of unbound S-VER was about 1.7 times its antipode. The binding constants of two enantiomers, KR-VER and KS-VER, were 2670 and 850 M-1, respectively. However, no obvious stereoselective binding of propranolol (PRO) to HSA was observed. Trimethyl-beta-cyclodextrin (45 mM) was used as a chiral selector in pH 2.5 phosphate buffer. Several drug systems were studied by the method. When ibuprofen (IBU) was added into VER-HSA solution. R-VER was partially displaced while S-VER was not displaced at all. A binding synergism effect between bupivacaine (BUP) and verapamil was observed and further study suggested that verapamil and bupivacaine occupy different binding site of HSA (site II and site III, respectively).