安徽省旅游星级饭店地域差异研究

根据2000～2005年安徽省星级饭店统计资料,利用变异系数这一度量标准分析了安徽省饭店在时间序列上和星级结构上的地域差异,结果表明:随着时间的变化饭店总数在各市间的差异在渐渐缩小.星级结构上五星级饭店地域分异程度最大,其次依次为一星级、四星级、三星级和二星级,通过安徽省各市国内旅游收入区位商和餐饮住宿业就业人员区位商与各市星级饭店数量相对水平的比较,找出不符合一般趋势的城市加以讨论.最后,运用SPSS分析软件对安徽省17个地市的星级饭店发展水平进行聚类分析,并讨论了运行结果所分出的4类城市,提出了饭店业发展的若干建议.     

Analysis of the weightiness of site effects on reinforced concrete (RC) building seismic behaviour: The Adra town example (SE Spain)

The damage distribution in Adra town (south‐eastern Spain) during the 1993 and 1994 Adra earthquakes (5.0 magnitude), that reached a maximum intensity degree of VII (European Macroseismic Scale (EMS scale)), was concentrated mainly in the south‐east zone of the town and the most relevant damage occurred in reinforced concrete (RC) buildings with four or five storeys. In order to evaluate the influence of ground condition on RC building behaviour, geological, geomorphological and geophysical surveys were carried out, and a detailed map of ground surface structure was obtained. Short‐period microtremor observations were performed in 160 sites on a 100m × 100m dimension grid and Nakamura's method was applied in order to determine a distribution map of soil predominant periods. Shorter predominant periods (0.1–0.3 s) were found in mountainous and neighbouring zones and larger periods (greater than 0.5 s) in thicker Holocene alluvial fans. A relationship T = (0.049 ± 0.001)N, where T is the natural period of swaying motion and N is the number of storeys, has been empirically obtained by using microtremor measurements at the top of 38 RC buildings (ranging from 2 to 9 storeys). 1‐D simulation of strong motion on different soil conditions and for several typical RC buildings were computed, using the acceleration record in Adra town of the 1993 earthquake. It is noteworthy that all the aforementioned results show the influence of site effects in the degree and distribution of observed building damage. Copyright © 2007 John Wiley & Sons, Ltd.     

地形对地转适应和锋生的影响

作者的目的是分析地形对由于热力差异所引起的局地锋生现象和地转适应过程的影响．为此，分别用零位涡流和均匀位涡流来近似代替实际大气，并借助位涡、绝对动量、位温的守恒关系，就地形对适应锋生和适应过程中能量转换等问题进行了简单讨论。初始位温扰动的水平分布及其相对于地形的位置对适应锋生有重要影响。当初始热力扰动主要位于地形迎风坡山脚时，地形不利于锋面形成，这时要形成锋面不连续，初始位温梯度的水平变化必须非常显著；当初始热力扰动主要位于山顶附近时，地形促进流体运动的辐合，有利于锋面不连续的形成，这时即使初始位温梯度的水平变化不是很大，也可能会形成锋面；当初始热力扰动主要位于背风坡时，地形是否有利于锋面不连续的形成取决于流体的层结情况，如果流体的基本层结很弱，地形促进锋面不连续的形成，反之，地形不利于锋面不连续的形成，这种差异主要是由于在这两种情况下，地形引起的下沉增温效应的强弱是不同的。另外，地形对地转适应过程中动能和位能之间的能量转换率也有影响，与没有地形的情况相比，当初始热力差异显著区位于迎风坡时，能量转换率减小，当不平衡场位于背风坡时，能量转换率增加，原因是在迎风坡流体要克服重力作功，在背风坡重力对流体作正功。     

New progress of research on water cycle in atmosphere in China

New progresses are introduced briefly about the water cycle study on atmosphere of China made in recent years. The introduction includes eight aspects as follows: 1) precipitation characteristics, 2) stability of climatic system, 3) precipitation sensitive region, 4) regional evaporation and evapotranspiration, 5) water surface evaporation, 6) vegetation transpiration, 7) cloud physics, and 8) vapor source.     

Petrographic and geochemical evidence for the formation of primary, bacterially induced lacustrine dolomite: La Roda 'white earth' (Pliocene, central Spain)

Upper Pliocene dolomites (‘white earth’) from La Roda, Spain, offer a good opportunity to evaluate the process of dolomite formation in lakes. The relatively young nature of the deposits could allow a link between dolomites precipitated in modern lake systems and those present in older lacustrine formations. The La Roda Mg‐carbonates (dolomite unit) occur as a 3·5‐ to 4‐m‐thick package of poorly indurated, white, massive dolomite beds with interbedded thin deposits of porous carbonate displaying root and desiccation traces as well as local lenticular gypsum moulds. The massive dolomite beds consist mainly of loosely packed 1‐ to 2‐μm‐sized aggregates of dolomite crystals exhibiting poorly developed faces, which usually results in a subrounded morphology of the crystals. Minute rhombs of dolomite are sparse within the aggregates. Both knobbly textures and clumps of spherical bodies covering the crystal surfaces indicate that bacteria were involved in the formation of the dolomites. In addition, aggregates of euhedral dolomite crystals are usually present in some more clayey (sepiolite) interbeds. The thin porous carbonate (mostly dolomite) beds exhibit both euhedral and subrounded, bacterially induced dolomite crystals. The carbonate is mainly Ca‐dolomite (51–54 mol% CaCO₃), showing a low degree of ordering (degree of ordering ranges from 0·27 to 0·48). Calcite is present as a subordinate mineral in some samples. Sr, Mn and Fe contents show very low correlation coefficients with Mg/Ca ratios, whereas SiO₂ and K contents are highly correlated. δ¹⁸O‐ and δ¹³C‐values in dolomites range from ?3·07‰ to 5·40‰ PDB (mean=0·06, σ=1·75) and from ?6·34‰ to ?0·39‰ PDB (mean=?3·55, σ=1·33) respectively. Samples containing significant amounts of both dolomite and calcite do not in general show significant enrichment or depletion in ¹⁸O and ¹³C between the two minerals. The correlation coefficient between δ¹⁸O and δ¹³C for dolomite is extremely low and negative (r=?0·05), whereas it is higher and positive (r=0·47) for calcite. The lacustrine dolomite deposit from La Roda is interpreted mainly as a result of primary precipitation of dolomite in a shallow, hydrologically closed perennial lake. The lake was supplied by highly saturated HCO₃^?/CO₃^2? groundwater that leached dolomitic Mesozoic formations. Precipitation of dolomite from alkaline lake waters took place under a semi‐arid to arid climate. However, according to our isotopic data, strong evaporative conditions were not required for the formation of the La Roda dolomite. A significant contribution by bacteria to the formation of the dolomites is assumed in view of both petrographic and geochemical evidence.     

Skarns and Genesis of the Huanggang Fe-Sn Deposit, Inner Mongolia, China

Abstract: The skarns and genesis were studied of the Huanggang Fe‐Sn deposit and the nearby Sumugou Zn‐Pb deposit in Inner Mongolia, China. In the Huanggang mine, Nos. 1 to 4 Fe ore bodies are arranged along a calcareous horizon from proximal to distal in this order to a granite intrusion named Luotuochangliang, while Sn ore body is situated near another granite intrusion named 204. According to the distance from the granitic intrusions, mineral assemblages in skarns are systematically changed. Garnet is the most predominant skarn mineral throughout the deposit. Hastingsitic amphiboles, however, predominate in the proximal skarns. Fluorite is common in the proximal skarns, while instead calcite is common in the distal skarns. Chlorite is characteristically present only in No. 3 ore body, and chlorite geothermometry gives near 300C for the mineralization of later stage. When garnet crystal shows zonal structure, isotropic andraditic garnet occupies the core, and is surrounded with anisotropic less‐andraditic garnet. The presence of white skarn along the boundary between main skarns and host sedimentary rocks confirms relatively reducing environment prevailing as a whole in the studied area. However, the compositional relation between coexisting garnet and clinopyroxene demonstrates that relatively oxidizing condition was achieved for garnet skarn and magnetite ore in the distal, Nos. 2 to 4 Fe ore bodies and Sumugou deposit, compared to that for garnet skarn in the proximal, No. 1 and Sn ore bodies. Preliminary study on the tin content of garnets in the studied area revealed a certain degree of contribution brought from granitic intrusives since the early stage of skarn formation, irrespective of proximal or distal. Oxygen isotope study on garnet, magnetite, quartz and skarn calcite, as well as hydrogen isotope study on hastingsitic amphibole, demonstrates mainly meteoric water origin for the skarn– and ore‐forming solutions. The occurrence of Sn, W, Mo and F minerals indicates that those elements were mainly supplied to the deposit later than the formation of skarns and iron ores, overlapping to them. These constraints allow to delineate the formation model of the deposit as follows (Fig. 10): At the time of late Jurassic to early Cretaceous, felsic activity occurred in this region as a part of Yanshanian magmatism, and formed granitic intrusions as well as thick volcanic piles on the surface. The circulation of meteoric water was provoked by the heat brought by the intrusions. By this circulation, much amount of iron was extracted from andesites of the Dashizhai Formation, and precipitated as skarns and magnetite ores along calcareous horizons near the bottom of the Huanggangliang Formation. Subsequently, volatile‐rich fluids with Sn, W and Mo were expelled from the solidifying granitic magmas, and precipitated these metals in the pre‐existing skarns and ores.     

Ponderomotive effects in magnetospheric hydromagnetic waves

The ponderomotive force (PMF) is a ubiquitous nonlinear wave effect arising in plasma physics when applied wave fields or plasma parameters have significant spatial gradients. Some basic properties of the PMF are described as they relate to ULF hydromagnetic waves in the magnetosphere. Examples are given of recent results obtained using both analytical and numerical techniques for waves from the lowest frequencies (determined by the dimensions of the magnetosphere) up to the vicinity of the ion cyclotron frequency. These results include the possibilities that the PMF may transport plasma over large distances in the magnetosphere, and that the PMF may energize magnetospheric ions significantly. In particular the PMF may play a role in transporting and energizing O⁺ ions from the ionosphere into the body of the magnetosphere. The PMF can also generate nonlinear coupling between the slow magnetosonic mode and the other hydromagnetic modes. This should lead to limitation of density enhancements and, notably in the case of standing Alfvén waves, to spatial harmonic generation, secularly growing frequency shifts, and saturation of driven wave fields. Some implications of these results for the magnetosphere are discussed.Based on an invited review given in IAGA Symposium 3.07, Nonlinear and Kinetic Effects in ULF Waves, at the IUGG XXI General Assembly, Boulder, Colorado, July 2-14, 1995.     

NO2 total column evolution during the 1989 spring at Antarctica Peninsula

Ground-based visible differential absorption spectrometry during twilight has been used for NO₂ total column observations at the Antarctica Peninsula, Marambio Base (64S, 56W), during the austral spring of 1989 (9 September to 25 November).Results show moderate NO₂ vertical column levels of 1.5 to 2.5×10¹⁵ molec cm^-2 in the morning and 2 to 3×10¹⁵ molec cm^-2 in the evening until middle October, highly modulated by planetary wave activity. From that date until the end of the period, a steady increase occurs which is associated with the rising of lower stratosphere temperature as the vortex weakens, reaching values of 5×10¹⁵ molec cm^-2 in late November, with small a.m.-p.m. differences. NO₂ is found to be positively correlated to both total ozone and 50 hPa temperature during the entire spring. However, when analyzing the departures from linear trends, a highly negative correlation has been observed from day 301 onwards.     

广西丹池成矿带芒场矿田岩浆岩源区特征及锆石U-Pb年龄分析

丹池成矿带是我国重要锡多金属成矿带,过去对丹池成矿带成岩成矿研究主要集中在大厂矿田及五圩矿田,而对丹池成矿带北部的芒场矿田岩浆作用时代、源区特征及其成矿性缺少分析。芒场矿田岩浆活动强烈,发育隐伏斑状花岗岩及有关的花岗斑岩脉和隐伏细粒花岗斑岩及有关的白云母花岗斑岩脉。本文分析花岗斑岩脉U-Pb年龄及花岗斑岩脉和白云母花岗斑岩脉主、微量元素组成,以探讨岩浆活动时代、岩浆源区特征及其成矿潜力。芒场矿田花岗斑岩脉锆石U-Pb年龄为89.1±0.9Ma (MSWD=0.9),和丹池成矿带内大厂矿田岩浆活动时代相近,表明丹池成矿带岩浆活动时代都发生于90Ma左右。白云母花岗斑岩脉具高A/CNK比值(2.69～2.88),含高铝硅酸盐矿物白云母及在Th-Rb图上沿S型花岗岩趋势线分布,和大厂矿田S型黑云母花岗岩的特征基本一致,表明其主要为S型花岗岩。花岗斑岩脉形成时代晚于白云母花岗斑岩脉,但其具有更低的SiO_2含量和更高的MgO、Fe_2O_3~T、CaO和TiO_2含量,且在SiO_2与TiO_2、Fe_2O_3~T、Al_2O_3和P_2O_5关系图中分布于不同区域,没有线性变化关系,显示两者不是同一岩浆结晶分异演化形成的,而为不同沉积变质岩部分熔融形成的。白云母花岗斑岩脉富Al_2O_3、K_2O、Rb、Cs、Sn、W、Nb和Ta,在Rb/Ba-Rb/Sr图上位于富粘土源区,为强风化作用形成的富粘土质富稀有金属源区部分熔融形成的产物。华南西部基底发育经强风化作用形成的富粘土质富稀有金属元素沉积变质源区,为华南西南缘大规模锡矿床的形成提供了物质基础。     

Palaeomagnetism of the Lower Cretaceous Sierra De Los Condores Group Cordoba Province Argentina

Measurements are described of the directions of remanent magnetization of 89 samples from nine lava flows and red beds. Stable remanent magnetization was isolated after AC demagnetizing. All the units have normal remanent magnetization, except one lava flow which yields a direction toward the north with positive inclination. From the mean direction of stable remanence, referred to the bedding, of each unit a virtual geomagnetic pole is computed; the mean of eight of these poles is 90·6 °E, 84·2° South, α₉₅= 4·7° and represents the position of the palaeomagnetic pole for the exposures of the Sierra de Los Condores group from El Estrecho-Cerro Libertad. The position of this pole is reasonably close to the positions of the South American Lower Cretaceous palaeomagnetic poles for the Serra Geral and Vulcanitas Cerro Colorado formations and the trachybasaltic dykes from Rio Los Molinos. This supports the interpretations that the South Atlantic Ocean was formed in Lower Cretaceous times and that the Earth's magnetic field was on average similar to that of a geocentric dipole in South America in the Lower Cretaceous, and suggests that there has not been substantial relative movements between Central Argentina and Southern Brazil.