Fourier techniques for an analysis of eclipsing binary light curves. VIa

The aim of the present paper is to deduce relations between the integral transformsA _2m, B_2m,andF _1,2 of the light curves of eclipsing binary systems. The integral transformsA _2m, B_2m,andF _1,2 have been related to one another by means of finite or rapidly converging infinite summations obtained by integrations of the series expansions of trigonometric functions.     

苏丹白垩纪碎屑岩中的柱状节理与裂谷肩旋转

笔者在苏丹西部Mellit地区白垩系碎屑岩中发现一种罕见的柱状节理,经研究认为是沉积岩层受到中新世喷发的玄武岩溶岩流的烘烤而失水收缩形成的。可以合理地假定柱状节理在形成时是垂直于大地基准面的,根据柱状节理和沉积岩层的产状,笔者计算出Mellit地块的两期旋转事件:自晚白垩世初期到中新世初期该地块向338°方向倾斜了18°.而自中新世以来又向138°方向倾斜了18°、经过详细分析非洲大陆西部、北部、中部和东部中新生代裂谷带的构造演化史后发现:Mellit地块实际上位于南苏丹裂谷带的西北裂谷肩上,该地块自晚白垩世初期至中新世初期,向NW方向倾斜是南苏丹裂谷带干裂谷化阶段造成的裂谷肩块体的向外旋转;该地块自中新世以来向SE方向倾斜是南苏丹裂谷带在后裂谷热沉降阶段造成的裂谷肩块体的向内旋转。而南苏丹裂谷进入后裂谷热沉降阶段是与新生代东非裂谷带和红海的发育分不开的。     

Serpentinites and their tectonic signature along the Northwest Zagros Thrust Zone, Kurdistan Region, Iraq

Two types of serpentinized peridotites are distinguished within the Northwest Zagros Thrust Zone (NW-ZTZ) in Kurdistan region of Iraq. One is found as lower members of ophiolite sequences, such as the Mawat and Penjwin ophiolites of the upper Cretaceous age. The other is represented by intraformational isolated serpentinite bodies in Betwat, Qaladeza, and Qalander areas within the Walash–Naopurdan volcano-sedimentary unit of the Paleocene to Eocene paleo-arc tectonic setting. Serpentinites within the NW-ZTZ consist mainly of lizardite and chrysotile, with subordinate amounts of syn-serpentinization magnetite, carbonates, chromium chlorite, tremolite, and talc as secondary minerals, and olivine, clinopyroxene, and chromian spinel as primary minerals. Minor antigorite is also found in the sheared serpentinites often found in ophiolite sequences. Petrological and geochemical studies of serpentinites from the NW-ZTZ show that, of the original protoliths of serpentinites, those associated with ophiolites are residual depleted harzburgite and dunite. The $ {\text{Cr}}\# \left( {{{ = {\text{ Cr}}} \mathord{\left/ {\vphantom {{ = {\text{ Cr}}} {\left( {{\text{Cr}} + {\text{Al}}} \right){\text{ atomic ratio}}}}} \right. \kern-0em} {\left( {{\text{Cr}} + {\text{Al}}} \right){\text{ atomic ratio}}}}} \right) $ of chromian spinel is more than 0.6, and the forsterite content of olivine is 91–92. On the other hand, the original protolith of isolated serpentinite bodies is less depleted harzburgite or depleted lherzolite, which has spinel with Cr# less than 0.6 and olivine with 90–91 forsterite contents. Whole rock chemistry of major, trace, and rare earth elements shows that the serpentinites of ophiolite sequences are depleted in CaO, Al₂O₃, and SiO₂, Sr, and Zr, and are enriched in MgO, Ni, and Cr, in comparison with the isolated serpentinites. Cr# of the disseminated unaltered chromian spinels indicates that the serpentinites of both types had been originated from the supra-subduction zone tectonic setting; the serpentinites of ophiolite sequences obducted and thrusted over the continental margin during the obduction of the Tethyth oceanic crust onto the Arabian continental margin during the upper Cretaceous period. Isolated serpentinite bodies represent serpentinized forearc mantle wedge peridotites emplaced by diapiric upwelling into non-accretionary forearc tectonic settings during the Paleocene to Eocene age.     

Reservoir Quality Assessment of the Upper Permian Chhidru Formation,Salt and Surghar Ranges,Pakistan

The Late Permian succession of the Upper Indus Basin in northeastern Pakistan is represented by the carbonate-dominated Zaluch Group, which consists of the Amb, Wargal and Chhidru formations, which accumulated on the southwestern shelf of the Paleo-Tethys Ocean, north of the hydrocarbon-producing Permian strata of the Arabian Peninsula. The reservoir properties of the mixed clastic-carbonate Chhidru Formation (CFm) are evaluated based on petrography, using scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and x-ray diffraction (XRD) techniques. The diagenetic features are recognized, ranging from marine (isopachous fibrous calcite, micrite), through meteoric (blocky calcite-I, neomorphism and dissolution) to burial (poikilotopic cement, blocky calcite-II-III, fractures, fracture-filling, and stylolites). Major porosity types include fracture and moldic, while inter- and intra-particle porosities also exist. Observed visual porosity ranges from 1.5%–7.14% with an average of 5.15%. The sandstone facies (CMF-4) has the highest average porosity of 10.7%, whereas the siliciclastic grainstone microfacies (CMF-3) shows an average porosity of 5.3%. The siliciclastic mudstone microfacies (CMF-1) and siliciclastic wacke-packestone microfacies (CMF-2) show the lowest porosities of 4.8% and 5.0%, respectively. Diagenetic processes like cementation, neomorphism, stylolitization and compaction have reduced the primary porosities; however, processes of dissolution and fracturing have produced secondary porosity. On average, the CFm in the Nammal Gorge, Salt Range shows promise and at Gula Khel Gorge, Trans-Indus, the lowest porosity.     

A determination of secular terms in first-order planetary theory

The secular terms of the first-order planetary Hamiltonian is determined, by two methods, in terms of the variables of H. Poincaré, neglecting powers higher than the second in the eccentricity-inclination.     

Continuous velocity fields for the T‐bar problem

This paper deals with the problem of T‐bar penetration. New kinematically admissible velocity fields are derived from elastic solutions of incompressible material using Airy stress function. These velocity fields are used to obtain upper bounds to collapse loads. Two particular solutions are presented, one for a rough contact surface between the T‐bar and soil and the other for a smooth contact surface. The merit of the solutions is that within the boundaries of the velocity field, the soil is required to shear compatibly and continuously. Therefore, these solutions can easily be combined with the strain path method to estimate rate and softening effects. Analysis including consideration of strain rate effect showed that the new mechanisms predict, under certain conditions, lower values than previously published upper bound solutions. Copyright © 2007 John Wiley & Sons, Ltd.     

The construction of a third order secular analytical J-S-U-N theory by Hori-Lie technique

We construct the outline of a third order secular theory for the four major planets. We apply the Hori-Lie technique to solve the problem. We take into consideration both parts of the perturbing function. Our canonical variables are those of H. Poincaré. Our periodic terms are the only 2:5 and 1:2 critical terms of J-S and U-N respectively. Terms of degree higher than the second in the Poincaré canonical variables H, K, P, Q are neglected.     

Fourier techniques for an analysis of eclipsing binary light curves: II

Some properties of the quantitiesB _2m (Smith, 1977) inherent in the frequency-domain approach have been deduced, and a general expression for them in terms of the eclipse elementsr _1,2,i andL ₁ of the basic model has been presented (Section 2).An expansion for the loss of light (1–l) into a Fourier sine series alone have been introduced, and its coefficientsb _m presented (Section 3) in terms of the same eclipse elements. A method of increasing the rate of convergence of this series has been given in Section 4. The methods for obtaining the elements of eclipsing binaries by making use of all these quantities in the frequency-domain can likewise be generalized to cover the photometric effects of gravitational and radiative interaction between the components.