Light curve analysis for eclipsing systems with exoplanets. The system HD 209458

We have analyzed precision light curves for HD 209458, a binary with an exoplanet. The parameters obtained at different epochs and different wavelengths are in good mutual agreement when confidence regions are used to calculate the uncertainty intervals. We demonstrate the effectiveness and reliability of our new method for estimating the uncertainty intervals. Reliable estimates are provided for the linear and quadratic limb-darkening coefficients of the star and their confidence intervals (uncertainties). We find that the wavelength dependence for the limb-darkening coefficients at λ = 3201?9708 Å differs significantly from the corresponding theoretical relation based on thin model stellar atmospheres.     

The eclipsing WN3(h)+O5V binary BAT99-129: Light curve analysis and parameters of its components

We have analyzed the broad-band light curve of the massive eclipsing binary BAT99-129, which is located in the Large Magellanic Cloud and consists of WN3(h) and O5V components. The light curve was obtained as part of the MACHO project. The dense extended atmosphere of the Wolf-Rayet (WR) star makes it impossible to apply a standard parametric model, such as that of Wilson and Devinney, to analyze the light curve. We reconstructed the distributions of the brightness and absorption across the disk of the WR component by directly solving the integral equations describing the eclipses in the system. Our analysis yields reliable estimates of the system’s orbital parameters and the parameters of its components. The orbital inclination is 78°, the size of the orbit 28.5 R _⊙, and the radius of the O component R _O = 7.1 R _⊙. The size of the WR core, which is opaque in the optical continuum, is R _WR = 3.4 R _⊙, and the brightness temperature at the center of the WR-component disk is T _br = 45 000 K. We discuss possible uncertainties in the parameters obtained. The derived information is used to draw conclusions about the system’s evolutionary status.     

PROCEEDINGS OF THE SECOND ANNUAL MEETING OF THE GEOLOGICAL SOCIETY OF CHINA, HELD IN PEKING, JANUARY 5, 6, AND 7, 1924.

Morning Session of Saturday, January 5. President V. K. Ting in the Chair. The first session of the Second Annual Meeting was called to order at 10 o'clock a. m., Saturday, January 5 in the Library Building of the National Geological Survey of China, Peking, by President Dr, V. K. Ting.     

Synthesis and Stability Relations of Mg--Al Pumpellyite, Ca4Al5MgSi6O21(OH)7

Hydrothermal synthesis and investigations of stability relationsof Mg—Al pumpellyite were conducted using high-pressurecold-seal apparatus over the temperature range 250–600°C and 2–8 kb P_fluid. Mg—Al pumpellyite Ca₄Al₅MgSi₆O₂₁(OH)₇was synthesized from partially crystalline gel mixtures of stoichiometriccomposition at 275–410 °C, 6–9 kb P_fluid, andruns of 7–90 days. Pure monomineralic synthetic Mg—Alpumpellyite has refractive index n_ß = 1.624 (2) andcell dimensions = 8.825 (8) Á, b = 5.875 (5) Á,c = 19.10 (1) Á, and ß = 97.39 (7)°. The high temperature assemblage of the equivalent bulk compositionconsists of clinozoisite, hydrogrossular/grossular, aluminousseptechlorite/chlorite, quartz, and H₂O. Hydrogrossular wassynthesized in the presence of quartz at 8 kb from 400–500°C, and hydrogrossular + quartz are unstable with respectto grossular + H₂O at 400 °C and 8 kb P_fluid. At 8 kb P_fluid,aluminous septechlorite forms at temperatures below 500 °Cwhereas aluminous 14 Á chlorite crystallizes at 500–600°C. The equilibrium relations of Mg—Al pumpellyite were determinedusing subequal mixtures of synthetic Mg—Al pumpellyiteand its high temperature assemblage. The reaction 9 Mg—Alpumpellyite = 9 clinozoisite + 6 grossular + 2 chlorite + 4quartz + 19 H₂O occurs at temperatures of 390 °C at 8 kb,368 °C at 5 kb, and near 325 °C at 2 kb P_fluid. Thereversal data yield an approximate value of –3141 joules/mole°K for the standard entropy of formation for the syntheticMg—Al pumpellyite. The Schreinemakers' relations for pumpellyite, prehnite, clinozoisite,tremolite, grossular, and amesite in the presence of excessquartz and fluid were constructed in the pseudo-ternary systemCaO–Al₂O₃–MgO(SiO₂–H₂O). The results, togetherwith reconnaissance experiments on the reaction 4 Mg—Alpumpellyite + 2 quartz = 8 prehnite + aluminous septechlorite+ 2 H₂O, locate the invariant point [TR] at approximately 5.7kb P_fluid and 375 °C. The results of the present study arenot compatible with previous experimental data on the invariantpoint [GR]. The P–T oriented phase relations are used to interpretsome natural parageneses developed in low-grade metabasalticrocks recrystallized under conditions of low _co2. The high-temperaturestability relations of Mg—Al pumpellyite are useful todenote the onset of greenschist facies metamorphism in rocksof basaltic composition.     

The influence of grain-size analysis methods and sediment mixing on curve shapes and textural parameters: Implications for sediment trend analysis

To this day, deterministic physical models capable of explaining the evolution of grain-size distributions in the course of transport are still lacking. For this reason, various attributes of particle frequency distributions, in particular curve shapes and textural parameters, have for many decades been investigated for potential information about transport behaviour and size-sorting processes of sediments in numerous environments. Such approaches are essentially conceptual and hence rely heavily on the validity of the assumptions on which they are based. A factor which has to date been largely ignored in this context, is the fact that different methods of grain-size analysis (e. g. sieving, laser absorption and diffraction, settling velocity measurements), when applied to the same sample material, produce variable curve shapes, and hence incongruous textural data. This is illustrated by selected examples showing the differences between sieving and settling results, conversion of settling velocities into equivalent settling diameters (psi-phi-transformations), and the influences of particle shape, particle density, and water temperature. It is demonstrated that particle-size distributions are not only method-dependent but also dependent on the adopted post-processing procedure. As a result, only frequency curves generated by the same method and subsequently processed by identical computational procedures can be meaningfully compared. Furthermore, the computation of textural parameters from bi- or multimodal size distributions produces spurious results which are unrelated to the processes leading to the mixing of different size populations frequently observed in nature. In such cases, only the decomposition of such distributions into individual populations and the spatial comparison of such populations makes any sense. Because a physical explanation for the generation of size distributions is lacking, a particular curve shape of a grain-size population has no meaning on its own. Only a systematic comparison of progressively changing curve shapes (and associated textural parameters) of sediments collected on a closely spaced grid can yield data suitable for sediment trend analysis.     

The earthquakes and related tsunamis of October 6, 1944 and March 7, 1867; NE Aegean Sea

During two distinct earthquakes occurred on March 7, 1867 and October 6, 1944, tsunami waves were also observed at some localities around the Gulf of Edremit, NE Aegean Sea. The first event (M _w = 6.8) mostly affected the city of Mitilini of Lesvos Island while the Gulf of Edremit-Ayvacık earthquake (M _S = 6.8) largely affected the northern and eastern coastal areas of the Gulf of Edremit. In 1944 earthquake, numerous surface cracks and water gushes were reported. The coastal neighborhoods of the town of Ayvalık in the east were flooded by tsunami waves. At the WSW extend of the main fault observed on land, which is parallel to the present-day slip vectors, some normal-oblique faults were observed close and subparallel to the northern coast. On the basis of historical documents, reports, interviews, geological setting, field observations and marine seismic reflection data, the 1944 earthquake was not triggered by one of the main fault segments but by a secondary fault or fault group which was described in this study. Depending on the distribution of tensional and compressional forces in the region, which rotates clockwise under the control of the middle strand of the North Anatolian fault, secondary fault groups become important. The moment tensor parameters of such small-size events have been determined and have obtained consistent results with the faults proposed in this study.     

Single-station ellipticity retrieval and its joint inversion with dispersion curve,for a borehole test site

To obtain the shear wave velocity profile for engineering application to near-subsurface, many geophysical techniques are used. The dispersion curve alone is unable to provide deeper shear wave velocity information for deep soil deposit; therefore, a joint inversion of dispersion curves with the horizontal over vertical (H/V) (i.e., apparently ellipticity) curve is recommended. The H/V curve obtained from the microtremor recording contains a major part of Love wave contribution to the noise wavefield horizontal component. Due to this presence of Love wave fraction, the H/V curve does not completely replicate the ellipticity of Rayleigh wave. In this study, we try to compare the Rayleigh wave ellipticity obtained from the borehole velocity model to the H/V curve obtained at the same locality from seismic ambient noise recording. Two different techniques available for the Love effect minimization are tested and compared with the borehole ellipticity. Finally, the joint inversion of H/V and dispersion curve is made, which shows great correspondence with the previous measurement at the site.     

上虞-三门高速公路6号大型滑坡稳定性分析及加固处理

浙江省上虞至三门高速公路6号滑坡,是全线施工过程中所遇到的最大滑坡.该段线路两侧山峰标高达400m左右,相对高差200余m,属丘陵地貌.该区段曾发生过三期古滑坡,斜坡经历了平衡→失稳→新的平衡不断发展的形成过程,在地形上呈"圈椅状",具古滑坡及崩塌地貌特征.滑坡体由崩积、崩坡积、古滑坡堆积物组成,滑带土主要为含碎块石粘性土.滑坡体长约600m,最厚处达44.95m,滑坡体积约为200万m3,属超深层大型堆积层滑坡.地下水在坡体中呈网管状分布,后缘及中部水位较浅,地下水位的变动一般滞后于降水1～2天.地面位移速率晴天为0.5～1.5mm/d,雨天为1.5～3.5mm/d,反映出降水对滑坡位移的强烈影响.采用CS-03型数显测斜仪,定期监测滑坡体在不同深度上的滑移状况,得出观测期间沿滑面的滑动速率为0.88mm/d.结合地质分析,准确判定了斜坡破坏的潜在滑面.本次滑坡的形成是自然地质因素与人为工程活动综合作用的结果,其形成机理可归纳为坡体的物质组成和特性、地下水的渗流作用和不利的地形条件使坡体具备了蠕滑变形的基本条件;公路施工在阻滑段挖方,减小了滑体的阻滑力,诱发了古滑坡复活.通过土工试验获取滑带土的强度参数,作为滑坡稳定性分析的基础参数.再用多断面的联合求解反分析检验,建议取滑面强度参数C=26?kPa和Φ=10.0°作为滑坡治理设计的依据.计算各断面分段终点的剩余下滑力,显示主要下滑推力来自滑体中段.由此,划分出次滑段、主滑段和阻滑段3个区段,以便采取不同的工程措施.对不同地下水位时坡体的稳定性进行验算,表明地下水位的升降对坡体的稳定性十分敏感.基于上述分析评价,考虑地下水位变动的滞后性,提出了地表和地下排水处理、多级抗滑桩支挡加固措施,以保证该路段边坡的稳定.地表排水按滑坡区段的地形布置,沿滑坡周界5m以外布设截水沟,在滑坡体地面上布设树枝状排水沟.在主滑段滑床以下的基岩中,横向设置断面1.6m×2.1m、长达305m的地下排水隧洞,隧洞上方滑体内设井径1.5?m的渗井30眼.分别在滑坡体的中上段、公路上坡和前缘等5处各设置1排嵌岩抗滑桩,采用了A型～D型和F型钢筋混凝土或钢筋混凝土预应力锚索桩,断面1.8×2.5、2×4、3×4m2、直径3m 4种,桩长15～35m,共计82根+62组,桩及系梁上设锚索294根.公路已建成通车1年多,监测表明该滑坡处于稳定状态.     

Three Secondary Reference Materials for Lithium Isotope Measurements: Li7-N, Li6-N and LiCl-N Solutions

The CRPG (Nancy, France) has prepared secondary reference materials for Li isotope measurements by mixing ⁷Li or ⁶Li spikes and either L-SVEC or IRMM-016 certified reference materials to produce solutions having a known Li concentration and isotopic composition. The Li7-N and Li6-N solution samples (1.5 mol l⁻¹ HNO₃) have nominal δ⁷Li isotopic compositions of 30.1‰ and -9.7‰ respectively relative to L-SVEC and concentrations of 100 mg l⁻¹. Repeated measurement of these samples using the QUAD-ICP-MS at the CRPG yielded δ⁷Li of 30.4 ± 1.1‰ (n = 13) and -8.9 ± 0.9‰ (n = 9) at the 2s level of confidence. An additional LiCl-N solution was measured and yielded a delta value of 9.5 ± 0.6‰ (n = 3). Identical results were obtained at the BRGM (Orléans, France) from determinations performed with a Neptune MC-ICP-MS (30.2 ± 0.3‰, n = 89 for the Li7-N, -8.0 ± 0.3‰, n = 38 for the Li6-N and 10.1 ± 0.2‰, n = 46 for LiCl-N at the 2s level of confidence). The deviation of measured composition relative to the nominal value for the Li6-N solution might be explained by either contamination during preparation or an error during sample weighing. These secondary reference materials, previously passed through ion exchange resin or directly analysed, may be used for checking the accuracy of Li isotopic measurements over a range of almost 40‰ and will be available to the scientific community upon request to J. Carignan or N. Vigier, CRPG.     

新郑天利两周墓地居民牙齿磨耗及口腔健康状况研究

本文对新郑市天利两周墓地居民的牙齿磨耗及口腔疾病进行了统计和分析,试图从古病理学的角度揭示当时居民的食物构成、饮食行为习惯及社会经济生活方式等。研究显示,天利两周墓地居民除了在牙釉质发育不良方面存在显著的两性差异,即男性明显高于女性外,在牙齿磨耗水平、牙齿生前脱落和龋病的患齿率上虽不存在明显的两性差异,但均表现为女性略高于男性。同时,与先秦时期不同地区、不同经济形态的古代居民相比,天利居民在前部牙齿,尤其是上颌前部的牙齿上表现出了较后部牙齿更为严重的磨耗。产生这些现象的原因一方面是天利墓地地处中原地区,旱作农业的谷类食物成为居民的主要食物来源,女性在牙齿生前脱落和龋病的患齿率及牙齿磨耗程度上略高于男性,说明两性在食物结构大致相同的情况下还存在少许差异,不同的劳动分工使得男性可能获得更多的动物性蛋白质和脂肪;对相关骨骼进行的稳定同位素分析显示,男性应该获取了比谷类食物更多的肉食,相对的,女性食物结构中的谷类比重则较大。另一方面,男性在牙釉质发育不良的患齿率上明显高于女性,说明该墓地的男性居民（尤其在幼年时期）普遍具有高于女性的生存压力;在牙釉质硬度降低、多用前部牙齿做工具使用及与女性相比,获取较多肉食的情况下,天利墓地男性居民相对于其他地区较明显的前部牙齿磨耗。

     

Chemical studies of L chondrites. V: compositional patterns for 49 trace elements in 14 L4-6 and 7 LL4-6 falls

To study compositional trends associated with open-system thermal metamorphism and shock-induced collisional breakup of L4-6 chondrite parent(s), we used inductively coupled plasma mass spectrometry and radiochemical neutron activation analysis to determine 49 trace elements in 62 falls. Trends for the 49 elements, especially of the 14 rare earth elements in 5 members of a putative L/LL group (Bjurböle, Cynthiana, Holbrook, Knyahinya, Sultanpur) and 9 additional L chondrites (Aïr, Aumieres, Bachmut, Forksville, Kandahar, Kiel, Milean, Narellan, Santa Isabel) differed markedly from those in the remaining normal 46 samples. Here, we report the data for the 14 L and putative L/LL chondrites and 7 LL (Appley Bridge, Athens, Bandong, Ensisheim, Mangwendi, Olivenza, Soko-Banja), analyzed to test the affinity of the putative L/LL suite to well-characterized LL chondrites.Compositional trends of the 14 atypical L chondrites (including Aïr’s unique and possibly contaminated signature) and Mangwendi, an LL6 chondrite, indicate that each is compositionally unrepresentative of well-sampled, whole-rock chondrites. Indeed, half of the unrepresentative chondrites were ≤ 2-g samples. Compositionally, members of the putative L/LL chondrites demonstrate no affinities to normal LL chondrite falls. To establish compositional trends accompanying open-system, thermal episodes involving the L chondrite parent(s), we should ignore data for the 14 unrepresentative L chondrites reported here.     

Application of Landsat 5 and Landsat 7 images data for water quality mapping in Mosul Dam Lake,Northern Iraq

Mosul Dam Lake is the main reservoir in Iraq, supporting the water demand of Mosul, Baghdad, and other cities. The aim of this study is to derive simple and accurate algorithms for the retrieval of water quality parameters for Mosul Dam Lake from Landsat 5 and Landsat 7 reflectance data. The water quality measurements were performed in situ during March and July 2011. These measurements included temperature, turbidity, Secchi disk, chlorophyll-a, nitrate, nitrite, phosphate, total inorganic carbon, dissolved organic carbon, total dissolved solids, and pH. In order to properly use the values of reflectance bands, images enhancement techniques have been used. The field measurements were compared with reflectance values of Landsat 5 and Landsat 7 bands using different band combination of empirical algorithms. Generally, the results of analysis showed significant correlation between these models and water quality parameters with R ²?>?0.7 and p?R ²?>?0.9 and p?R ²?>?0.9, and values of the root mean square error ranged from 0.9 to 0.001. ArcGIS 10 was used to simulate the distribution values of water quality parameters calculated from spectral values of TM5 and ETM+ bands. The results of spatial analysis demonstrate that it is possible to use the TM5 and ETM+ images to evaluate the water quality for Mosul Dam Lake.     

Polymerization of silicate and aluminate tetrahedra in glasses,melts, and aqueous solutions—I. Electronic structure of H6Si2O7, H6AlSiO71−, and H6Al2O72−

As part of a study of the effect of geologically common network modifiers on polymerization in silicate melts, glasses, and silica-rich aqueous solutions, we have studied the energies, electronic structures, and inferred chemical properties of ^IVT-O-^IVT linkages in the tetrahedral dimers H₆,Si₂O₇, H₆AlSiO₇^1?, and H₆Al₂O₇^2? using semi-empirical molecular orbital theory (CNDO/2). Our results indicate that the electron donating character of the bridging oxygen, O(br), linking two tetrahedra increases with increasing T-O(br) bond length but decreases with decreasing T-O(br)-T angles and increasing O-T-O(br) angles. This increase or decrease of the donor character of O(br) coincides with an increase or decrease of the affinity of O(br) for hard acceptors. The calculated electronic structure for the H₆Si₂O₇ molecule is compared with the observed X-ray emission, absorption, and photoelectron spectra of quartz and vitreous silica; the reasonable match between calculated and observed oxygen Kα emission spectra of vitreous silica supports our assertion that non-bonded O(br) electron density energetically at the top of the valence band controls the chemical reactivity of ^IVT-O-^IVT linkages in polymerized tetrahedral environments.     

Marine Isotope Stage 7–6 transition age for beach sediments at Morston,north Norfolk,UK: implications for Pleistocene chronology,stratigraphy and tectonics

Optically stimulated luminescence age estimates for the Pleistocene beach at Morston, north Norfolk, UK, obtained by the single‐aliquot regenerative‐dose protocol, indicate a Marine Isotope Stage (MIS) 7–6 transition date. The view that the beach is of Ipswichian (MIS 5e) age, held virtually unanimously for the last 75 years, may now be discarded. The extant beach sequence lies up to ～5 m OD, yet global models suggest that MIS 7–6 sea levels were typically substantially below that of today. The explanation may lie with poorly understood regional tectonic movements. The MIS 7–6 date helps to constrain the ages of glacial deposits that bracket the beach sediments at Morston. The underlying Marly Drift till cannot be younger than MIS 8; this may also be true for the complex assemblage of glaciogenic landforms and sediments, including the Blakeney esker, in the adjacent lower Glaven valley. The well‐established Late Devensian (MIS 2) age of the Hunstanton Till is not compromised by the date of the Morston beach. There is no indication of a proposed Briton's Lane glaciation during MIS 6 times. Copyright © 2009 John Wiley & Sons, Ltd.