玻片反射器的透射旋转及其实用

Based on the principles of physical, optics, the author has derived a formula for the calculation of the angle of rotation D, when transmitted polarized light passes through a dielectric. The theory of transmitted rotation of glass reflector is, too, discussed in the paper. It has been shown that for linear polarized light normal to the plane of incidence, the original angle of rotation will inerease and for that parallel to the plane of incidence the decrease of the original angle of rotation will be expected. With the formula derived, calculations are made for certain cases. The trial-measurements of angles of.transmitted rotation by the coated glassreflector of some ore microscopes have been carried Out and the results indicate that the theoretical calculations are well coincident with the practical measurements. Finally, a new way is suggested for the application of transmitted rotation.     

沉积岩中镁钠闪石石棉矿物的初步研究

Alkali amphibole asbestus is widely distributed in a Mesozoic terrestrial redbed.Preliminary mineralogical study shows that it belongs to magnesian riebeckite asbestus. The mineral contains higher Na, Mg and Fe^3 , lower Al, and is well comparable with that of typical magnesian riebeckite asbestus in chemical composition. A comparasion between the methods used for calculating the crystallochemical formula of amphibole indicatesthat the structural characteristics of amphibole can be best brought out if a total catian number of 15, i.e., x y z=15, is taken as the factor for magnesian riebeckite. The infrared spectra for fibrous magnesian riebeckite exhibit two definite absorption bands. The firat one is at 850--1250 cm^-1, involving several minor bands due to the valency vibration of Si--O, with maximum values of 975,1025, 1080cm^-1 respectively. The second absorption band which is attributable to the distortional vibration of Si--O--Si, is detected at 350--600cm^-1, with a maximum value of 440cm^-2. Optically, its refractien iadices bacrease with increasing transition elements, especiany the ratio of Mg/Mg Fe^2 Fe^3 Mn. A distinct exothermic effect is observed between 350--400℃, indicating the oxidation of Fe^3 to Fe^3 . A deep endothermic valley between 970--1020℃ can be attributed to the melting of magnesian riebeckite and the formation of new minerals. The auther oonsideres that fibrous magnesian riebeckite is crystallized in favorable accumulation strata from a Na-, Mg-, Fe-rich silicate colloidal solution that has been derived from country rocks by some alkline ground water duringg the process of sedimentation and diagenesis in terrestrial saline carbonate muds. Magnesian riebeckite formed at terrestrial carbonate saline formations promises to be a potentially important genesis type for alkali amphiboles.     

论玻片反射器的反射旋转

By introducing the calculation formula of reflected rotation angle, Rγβ, for linear polarized light in dielectric and absorption medium, it is confirmed that the amplitude of the reflected light shift nearly always towards the normal of incidence plane. The following conclusions may be drawn after the calculations of reflected rotation angles with respect to a variety of glass reflectors: (1) Glass reflectors coated by films of high refractive index are preferable because they havethe minimum reflected rotation. (2) When quantitative measurement of optical constants of opaque minerals is to be made, the polarizer of the ore microscope should be strictly oriented in E--W direction and special precautions are required in order to aviod any shifting from this position.     

Deformation Localization-A Review on the Maximum- Effective-Moment (MEM) Criterion

The essential difference in the formation of conjugate shear zones in brittle and ductile deformation is that the intersection angle between brittle conjugate faults in the contractional quadrants is acute(usually ~60°) whereas the angle between conjugate ductile shear zones is obtuse(usually 110°). The Mohr-Coulomb failure criterion, an experimentally validated empirical relationship, is commonly applied for interpreting the stress directions based on the orientation of the brittle shear fractures. However, the Mohr-Coulomb failure criterion fails to explain the formation of the low-angle normal fault, high-angle reverse fault, and the conjugate strike-slip fault with an obtuse angle in the σ1 direction. Although it is ten years since the Maximum-Effective-Moment(MEM) criterion was first proposed, and increasingly solid evidence in support of it has been obtained from both observed examples in nature and laboratory experiments, it is not yet a commonly accepted model to use to interpret these antiMohr-Coulomb features that are widely observed in the natural world. The deformational behavior of rock depends on its intrinsic mechanical properties and external factors such as applied stresses, strain rates, and temperature conditions related to crustal depths. The occurrence of conjugate shear features with obtuse angles of ~110° in the contractional direction on different scales and at different crustal levels are consistent with the prediction of the MEM criterion, therefore ~110° is a reliable indicator for deformation localization that occurred at medium-low strain rates at any crustal levels. Since the strain–rate is variable through time in nature, brittle, ductile, and plastic features may appear within the same rock.     

Bioleaching behavior and surface property of pyrites in different metallogenic conditions

The bioleaching behaviors and surface properties of pyrites in two metallogenic conditions by Sulfoba- cillus thermosulfidooxidans were investigated by adsorption tests, zeta-potential measurements and bioleaching ex- periments. It is found that there were significant differences in the microorganism adsorption capacity, electrokinetic properties and bioleaching behaviors for the two pyrites. The S. thermosulfidooxidans adsorption capacity on high temperature hydrothermal （hy high_temp） pyrite is larger than that on sendimentary coal （sed_coal） pyrite. It may be that more extracellular polymeric substances （EPS） is produced when it is difficult for microorganism to make use of hy high temp pyrite as source of energy, and get leaching bacteria attached to pyrite by means of EPS. The zeta-potential measurements indicated that zeta-potential value of hy_high_temp pyrite was higher than that of seal_coal pyrite in pH range of 2-10. After interacting with cells, the IEP （Iso-Electric Point） of hy_high_temp pyrite shifted obviously to that of bacterial. In contrast, the IEP of sed coal pyrite remained unchanged nearly. The bioleaching results showed that hy high_temp pyrite did not dissolve and the leaching extent was only 0.82%, while that of sed_coal pyrite was 34.59%. Attempts were taken to illustrate the remarkable difference between bioleaching results of two pyrites from a semiconductor energy band theory perspective.     

Effects of Tectonic Force on Hydrostatic Pressure in Crust

The research into the hydrostatic pressure in the crust has been previously conducted from the viewpoint that the hydrostatic pressure is equal to the gravity, based on the fact that the hydrostatic pressure is derived mainly from the gravity of its overlying rocks. In this paper, the stress state of any point in the crust is suggested to have been caused by both the gravity and the tectonic force. The author proposes that the hydrostatic pressure is a combination or superposition of two isotropic stresses in the tectonic force and gravity stress fields. The results obtained with a finite-element simulation indicate that the additional hydrostatic pressure borne by rocks decreases gradually from the compression zone (pc^s),the shear zone (psh^s) to the tensile zone (pt^s), and that the difference in the additional tectonic hydrostatic pressure between these deformed zones tends to increase, following the increase in the absolute value and/or the difference in external forces between different directions. This paper presents the foundation for the research into the tectonic physicochemistry.     

Mineral Resources and Their Comprehensive Utilization in China Sea

It was said that mineral resources in oceans might be a reliable source for the material production. Ocean water is regarded as a huge “liquid deposit” for its ability to dissolve many kinds of elements. The total amount of elements in ocean water is greater than that in land. At the seafloor or below, occur a large number of mineral resources besides those in the water.China Sea, situated in the junction between North China block, Yangtze block and the Pacific plate and the Philippines plate, is excellent in ore-forming geological conditions, resulting in the presence of many kinds of deposits and abundant reserves. Mineral resources found in China Sea mainly include oil-gas resources, sea-beach placer and submarine coalfield.In addition, the manganese nodule and cobalt-rich crust are also discovered in South China Sea. Furthermore, the hydrothermal metalliferous deposit and gas hydrate may also be present in South China Sea.     

3D Velocity Structure and Its Tectonic Implications in the East China Sea and Yellow Sea

3D structure of the crust and upper mantle in the studied area has been analyzed from surface wave tomography. The velocity distribution in the uppermost crust is symmetrical on two sides of the central line of the sea, and coincides with the structure of crystalline basement. The essential difference in tectonics between the East China Sea and the Yellow Sea mainly lies in that the velocity structures of their lower crust and upper mantle are identical to those of South China and North China respectively. In the upper mantle there exists a high-velocity zone with a nearly EW strike from the Hangzhou Bay, China, to the Tokara Channel, Japan, along about the latitude of 30°N. It is found that between the East China Sea and the Yellow Sea there are systematical differences in geomorphology, geology, seismicity, heat flow, quality factor and gravity and aeromagnetic anomalies, which is related to both left-lateral shear dislocation and right-lateral tear of the Benioff zone from the Hangzhou Bay to the Tokara Channel.It is inferred that the East China Sea was formed by Cenozoic back-arc extension. The boundary between the North China and South China crustal blocks stretches along the southern piedmont of Mts. Daba-Dabie-Hangzhou Bay-Tokara Channel, and the subduction zone at the Okinawa trench is the eastern boundary of the South China crustal block. The movements of the Pacific plate, Indian plate and upper mantle rather than the Philippine plate subduction have played a dominant role for the modern tectonic movements in East Asia.     

An Effective Method for Free Vibration of Plate on Elastic Half Space

The vibration analysis of a plate on an elastic foundation is an important problem in engineering. It is the interaction of a plate with the three-dimensional half space and the plate is usually loaded from both the upper and lower surfaces. The contact pressure from the soil can not be predefined. According to Lambs solution for a single oscillating force acting on a point on the surface of an elastic half space, and the relevant approximation formulae, a relation between the local pressure and the deflection of the plate has been proposed. Based on this analysis, the reaction of the soil can be represented as the deformation of the plate. Therefore, the plate can be separated from the soil and only needs to be divided by a number of elements in the analysis. The following procedure is the same as the standard finite element method. This is a semi-analytical and semi-numerical method. It has been applied to the dynamic analysis of circular or rectangular plates on the elastic half space, at low or high frequency vibration, and on rigid, soft or flexible foundations. The results show that this method is versatile and highly accurate.     

Desertification Risk Monitoring for North Shaanxi Province, China,Using Normalized Difference Vegetation Index（NDVI）

In this study,the remote sensing is applied to the examination of the relationship between desertification and normalized difference vegetation index(NDVI) in the context of northern Shaanxi Province.This relationship is also examined using spatial analysis methods.A strong negative correlation is found in the largest area desert,indicating that the relationship between desert and NDVI is not a sim-ple linear one and that the correlation coefficient between NDVI and vegetation abundance is significant.The normalized difference vegetation index(NDVI) was compared with other vegetation index-based methodologies.NDVI is a valuable first-cut indicator for such systems, although the analysis and inter-pretation of its relationship to desertification are complex and also based on the detailed analysis of its re-lationship to ecological zone,vegetation type and season.Conclusions thus made would help to upgrade the methodology as an effective tool for early-warning desertification in the northern Shaanxi Province where a drought is a recurring threat.This methodology includes the integration of NDVI with other socio-economic and bio-physical indicators in GIS ,the complementation of desert area data with satellite data,and the analysis of the relationship between NDVI and specific climatic zones,for each season and vegetation type.     

Relationships Between the North China Plate and the Tarim Plate

The relationships and boundary between the North China and Tarim plates have been unclear for a long time ; however, the two plates occupy a prominent position in the formation and evolution of the continental lithosphere of China. It is proposed that the Engger Us ophiolitic melange zone discovered recently north of Alaxa is a typical suture between the two plates. The ophiolitic melange zone is composed mainly of a mixture of fragments of ancient oceanic crust and sedimentary rocks of active and passive continental margins. The melange may be divided into tectonic inclusions and matrix. The suture extends northeastwards into the Republic of Mongolia and probably westwards to meet the Altun fault. With the Engger Us ophiolitic melange zone as the boundary the Alaxa area may be divided into two parts: the northern part (AN ) belongs to the Tarim plate, while the southern part (AS) the North China plate. Geological evidence shows that the two plates were amalgamated in the Late Permian or a bit later.     

Re-evaluation of linearity and precision of Gas Bench II-IRMS system and potential implications for carbon and oxygen isotope measurements on small-sized carbonate samples

In this study, the δ^13C and δ^18O values were systematically measured on NBS-18, NBS-19 and IAEA-CO-1 with different sample sizes, with the objective to examine the stability and reproducibility of previously developed linearity correction strategy especially for small-sized samples （e.g. 〈50 μg）. Firstly, the δ^13C and δ^18O values of NBS-19 standards （6-10 samples per run） with sample sizes scattered below -100 μg were determined in three different runs. The logarithmic regressions were performed on the plots of δ-values vs. peak area （sample size） for each run and the correction was applied using peak area of the first peak. Results show that two of the three data sets have almost the same regressive equations for both δ^13C and δ^18O values. The maximum difference in δ^13C values calculated by three equations when sample size varies between -10 and -100 μg is better than 0.15‰, compared with the maximum 0.82‰ for δ^18O values. Since alteration of phosphoric acids could not influence carbon isotope, the 〈0.15‰ difference in calculated δ^13C values should reflect the stability of mass spectrometer conditions. In contrast, the large difference in regressive equations for δ^18O values may be attributed to changed oxygen isotope in phosphoric acids due to exchange with atmosphere through time. It means that standards with sample sizes properly distributed should be arranged in every run for subsequent linearity correction of δ^18O values of small-sized samples （e.g. marine ostracode）.     

The Possible Topologic structure Types of Orthopyroxene with Space Group P21ca

The possible topologic structure types of orthopyroxene with space group P21ca comprise four kinds of tetrahedral chains and four kinds of octahedral sites.all of which are non-equivalent in symmetry,In these structure types,the skew of the octahedral layers has a sequence of --,There are sixteen possible combination forms for the rotation type of tetradral chain.Twelve of them violate Thompson ‘s sparity rule and the remainder constitutes two pairs.In each pair,the two polar forms show a relationship of anti-orientation for their polar a-axes.Thus,there are only two possible different topologic structure types for P21ca-orthopyroxene.The ratios of O-rotated and S-rotated tetrahedral chains for these two structure types are 3:1 and 1:3,respectively,In the view S-rotated tetrahedral chains for these two structure types are 3:1 and 1:3,respectively,In the view of crystallochemical principle,the most likely form is the one with a ratio of 3:1,and its constitutions of two stacks of I-beam,which are non-equivalent both in symmetry and in topology,are and the configurations of the two types of M2 sites are P.P and P.N,respectively,A complementary twinning on(100) would be formed between the anti-oriented structure pairs,and their twin boundary is exactly equivalent to the inversion boundary,Moreover,it is possible that the ordered structure would appear when the atom ratio of Mg:Fe is equal to 3:1 as well as to 1：1。     

The pulsar PSR B1931+24 as an orthogonal rotator

The angles of the magnetic moment μ and the line of sight L to the rotation axis Ω are estimated for the pulsar PSR B1921+24, which displays “on” and “off” periods in its radio emission. It is shown that this object is an orthogonal rotator, i.e., the angle β between μ and Ω is equal to 88°.2 and the angle between L and Ω is ζ = 98.7°, and that its rotation period should be twice the usually adopted value (P = 1.626 s). One possible reason for the peculiarities of this pulsar could be the precession of a relic disk in the equatorial region of the object. Further observations (in particular, in the infrared) are required to confirm the existence of such a disk. Polarization data for other pulsars whose radiation switches on and off (transients) are also required, to determine if they are likewise orthogonal rotators. Calculations for PSR B0656+14 show that β ∼ 20°, and the sharp increase of its pulse intensities is due to intrinsic reasons, and is not associated with a relic disk. Original Russian Text ? I.F. Malov, 2007, published in Astronomicheskiĭ Zhurnal, 2007, Vol. 84, No. 6, pp. 531–535.     

Application of Seismic Anisotropy Caused by Fissures in Coal Seams to the Detection of Coal-bed Methane Reservoirs

Coal-bed methane is accumulated in micro-fissures and cracks in coal seams. The coal seam is the source terrace and reservoir bed of the coal-bed methane (Qian et al., 1996). Anisotropy of coal seams is caused by the existence of fissures. Based on the theory of S wave splitting: an S wave will be divided into two S waves with nearly orthogonal polarization directions when passing through anisotropic media, i.e. the fast S wave with its direction of propagation parallel to that of the fissure and slow S wave with the direction of propagation perpendicular to that of the fissure.This paper gives the results of laboratory research and field test on the S wave splitting caused by coal-seam fissures: The results show that it is, feasible to detect fissures in coal seams by applying the converted S wave and finally gives the development zone and development direction of these fissures.     

On the evolution of terrestrial planets:Bi-stability,stochastic effects,and the non-uniqueness of tectonic states

The Earth is the only body in the solar system for which significant observational constraints are accessible to such a degree that they can be used to discriminate between competing models of Earth's tectonic evolution.It is a natural tendency to use observations of the Earth to inform more general models of planetary evolution.However,our understating of Earth's evolution is far from complete.In recent years,there has been growing geodynamic and geochemical evidence that suggests that plate tectonics may not have operated on the early Earth,with both the timing of its onset and the length of its activity far from certain.Recently,the potential of tectonic bi-stability(multiple stable,energetically allowed solutions)has been shown to be dynamically viable,both from analytical analysis and through numeric experiments in two and three dimensions.This indicates that multiple tectonic modes may operate on a single planetary body at different times within its temporal evolution.It also allows for the potential that feedback mechanisms between the internal dynamics and surface processes(e.g.,surface temperature changes driven by long term climate evolution),acting at different thermal evolution times,can cause terrestrial worlds to alternate between multiple tectonic states over giga-year timescales.The implication within this framework is that terrestrial planets have the potential to migrate through tectonic regimes at similar‘thermal evolution times'(e.g.,points were they have a similar bulk mantle temperature and energies),but at very different'temporal times'(time since planetary formation).It can be further shown that identical planets at similar stages of their evolution may exhibit different tectonic regimes due to random variations.Here,we will discuss constraints on the tectonic evolution of the Earth and present a novel framework of planetary evolution that moves toward probabilistic arguments based on general physical principals,as opposed to particular rheologies,and incorporates the potential of tectonic regime transitions and multiple tectonics states being viable at equivalent physical and chemical conditions.     

Burial Records of Reactive Iron in Cretaceous Black Shales and Oceanic Red Beds from Southern Tibet

One of the new directions in the field of Cretaceous research is to elucidate the mechanism of the sedimentary transition from the Cretaceous black shales to oceanic red beds. A chemical sequential extraction method was applied to these two types of rocks from southern Tibet to investigate the burial records of reactive iron. Results indicate that carbonate-associated iron and pyrite are relatively enriched in the black shales, but depleted or absent in red beds. The main feature of the reactive iron in the red beds is relative enrichment of iron oxides （largely hematite）, which occurred during syn-depostion or early diagenesis. The ratio between iron oxides and the total iron indicates an oxygen-enriched environment for red bed deposition. A comparison between the reactive iron burial records and proxies of paleo-productivity suggests that paleo-productivity decreases when the ratio between iron oxides and the total iron increases in the red beds. This phenomenon could imply that the relationship between marine redox and productivity might be one of the reasons for the sedimentary transition from Cretaceous black shale to oceanic red bed deposition.     

http://www.sciencedirect.com/science/article/pii/S1674987110000319

The 3-D geometry of the seismicity in Hindu Kush–Pamir–western China region has been defined by seismic records for 1975–1999 from the National Earthquake Information Center, the U.S. Geological Survey, and over 16,000 relocated earthquakes since 1975 recorded by the Xinjiang seismic network of China. The results show that most Ms ≥ 5.0 hypocenters in the area are confined to a major intracontinental seismic shear zone (MSSZ). The MSSZ, which dips southwards in Pamir has a north-dipping counterpart in the Hindu Kush to the west; the two tectonic realms are separated by the sinistral Chaman transform fault of the India–Asia collisional zone. We demonstrate that the MSSZ constitutes the upper boundary of a south-dipping, actively subducting Pamir continental plate. Three seismic concentrations are recognized just above the Pamir MSSZ at depths between 45–65 km, 95–120 km, and 180–220 km, suggesting different structural relationships where each occurs. Results from focal mechanism solutions in all three seismological concentrations show orientations of the principal maximum stress to be nearly horizontal in an NNW–SSE direction. The south-dipping Pamir subduction slab is wedge-shaped with a wide upper top and a narrow deeper bottom; the slab has a gentle angle of dip in the upper part and steeper dips in the lower part below an elbow depth of ca. 80–120 km. Most of the deformation related to the earthquakes occurs within the hanging wall of the subducting Pamir slab. Published geologic data and repeated GPS measurements in the Pamir document a broad supra-subduction, upper crustal zone of evolving antithetic (i.e. north-dipping) back-thrusts that contribute to north-south crustal shortening and are responsible for exhumation of some ultrahigh-pressure rocks formed during earlier Tethyan plate convergence. An alternating occurrence in activity of Pamir and Chaman seismic zones indicates that there is interaction between strike-slip movement of the Chaman transform fault system and deep-subduction of the Pamir earthquake zone. Pamir subduction-related seismicity becomes shallower in depth with increasing distance east of the transform fault. Therefore, sinistral movement of the Chaman transform fault appears to be influencing continental deep-subduction in the Pamir region and may provide an explanation for the unusual south-dipping geometry of the intracontinental Pamir plate.     

Theoretical Analyses of the Infrared Spectrum of Baiyuneboite—（Ce）

Baiyuneboite-(Ce) is a new fluor-carbonate mineral.Based on the fine data on the structure of the mineral,the factor group and normal coordinate analyses for its infrared spectrum have been carried out.The factor group analyses indicate that the site group and factor group splittings of the internal vibration bands of CO3^2- ions do not occur and that the double bands of normal modes result from two non-equal sets of CO3^2- ions in the crystal structure,The normal coordinate analyses give the stretching force constants.bend force constants and calculated frequencies of CO3^2- ions.The calculations of potential energy distribution allow us to assign v3 and v4 to the stretching vibration and the bend vibration of CO3^2- ions.respectively.     

Tomographic Imaging of the India-Asia Plate Collisional Tectonics and Mantle Upwelling Beneath Western Tibet

To better understand the lithosphere mantle collision tectonics between the India plate and Asia plate, we determine three dimensional P wave velocity structure beneath western Tibet using 27,439 arrival times from 2,174 teleseismic events recorded by 182 stations of Hi-CLIMB Project and 16 stations in the north of Hi-CLMB. Our tomographic images show the velocity structure significantly difference beneath northern and southern Qiangtang, which can further prove that the Longmu Co-Shuanghu ophiolitic belt is a significant tectonic boundary fault zone. There are two prominent high velocity anomalies and two prominent low velocity anomalies in our images. One obvious high velocity anomalies subduct beneath the Tibet at the long distance near 34°N, whereas it is broke off by an obvious low velocity anomaly under the IYS. We interpret them as northward subducting Indian lithosphere mantle and the low velocity anomanly under IYS likely reflects mantle material upwelling triggered by tearing of the northward subduction Indian lithosphere. The other prominent high velocity anomaly was imaged at a depth from 50 km to 200 km horizontal and up to the northern Qiangtang with its southern edge extending to about 34°N through Hoh Xil block. We infer it as the southward subducting Asia lithosphere mantle. The other widely low velocity anomaly beneath the Qiangtang block lies in the gap between the frontier of India plate and Asia plate, where is the channel of mantle material upwelling.