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1.
A mechanical model based upon elasticity theory for the deformation around a pressurized elliptical hole in an homogeneous, isotropic solid has found application in many areas of engineering, rock mechanics, and structural geology. The explicit equations for stress and displacement around such a hole are given. An apl computer program for calculating these stresses and displacements also is presented. These equations and this program should ease future usage of this model by engineers and geologists.  相似文献   

2.
Based on the methods of Fisher and Watson,Fortran iv computer programs are presented for the following analyses of directional observations on the sphere: (1) to determine if points are randomly distributed; (2) to estimate the azimuth and inclination of the center (mean direction) of a cluster and to estimate the precision (closeness) with which points are clustered; (3) to determine if two or more clusters have the same mean direction; (4) to determine if two clusters have the same precision of clustering; and (5) to locate the pole of a greatcircle girdle of points. Limitations of these analyses for undirected directional observations on the hemisphere also are given.  相似文献   

3.
An algorithm andFortran-iv computer program,cabfac, forQ-mode factor analysis is described. The program will accept up to 1500 items and 50 variables on a moderate-size computer.  相似文献   

4.
Methods for calculating constant terminal-settling velocities (vs)of spheres are examined for their validity and limitations of usefulness. A different approach is given which accurately predicts vs for spheres over a wide range of hydraulic conditions based on past experimental work. The theory behind this approach is given along with the listing of a fortran program which directs the calculations of vs.The practical limits of the author's method are stated, and tables of vs may be generated from the program for common mineral densities over a range of sizes useful to sedimentologists.  相似文献   

5.
Nonlinear regression methods can be used to fit functions for two related variables where both variables are subject to error. A computer program for nonlinear estimation described previously has been modified to fit such functions for a given set of data. A numerical example is provided for a second-degree equation in xand y.A closer fit to an observed set of data is possible if the error structure for the variables is specified.  相似文献   

6.
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7.
Many difficulties inherent in analyzing cyclical successions in terms of an idealized cycle and, to a lesser extent, in terms of the modal cycle and composite sequence can be overcome by structuring data in terms of probabilities of upward transitions from one lithology to another. This enables a finite Markov-process model to be used. Transition probability matrices have been constructed from two versions of the same borehole section through paralic Namurian (Pendleian Stage, E 1 ) sediments east of Stirling. The first version does not allow, but the second allows, adjacent items to be of the same lithology. The matrix derived from the first version indicates the following preferred upward succession of lithologies: coal, mudstone, siltstone, sandstone, seatclay, silty and sandy rooty beds, coal. A version of the Chi-square test strongly rejects the hypothesis that the lithologies were deposited in random order. The second matrix is used as computer input forTestmark, Stochex, andMarchain programs, the last of which stimulates a realistic vertical succession. The transition probability data fit readily into the broad framework of deltaic cycles.Published with permission of the Director, Institute of Geological Sciences.  相似文献   

8.
A computer aided design analysis using high-resolution laser scans of the bones of the stegosaur Kentrosaurus aethiopicus Hennig 1915 from the Late Jurassic Tendaguru Formation indicates that in the habitual walking pose the forelimbs were probably held erect, and that strong humeral flexion and abduction mainly occurred in a defensive stance. Rapid gaits with unsupported phases could not be used. The neck allowed sufficient lateral flexion to guarantee good sight in all directions including posteriorly. The tail covered an arch of roughly 180° and had sufficient range to be used as a weapon. Possibly, the animal could accomplish tail blows against specific targets in sight. Also, a tripodal pose is suggested to have been possible, roughly doubling the maximum vertical feeding height of Kentrosaurus.  相似文献   

9.
High-precision, computer-refined values of the cell parameters of calcium hydroxyapatite, Ca10(PO4)6(OH)2, have been determined with an X-ray diffractometer, internally standardized by means of sodium chloride. The results obtained are as follows: a 0=9.4192 Å c 0/a 0=0.731 c 0=6.8867 Å volume=529.2 Å3 The apatite work was supported by a research grant DE-02105 from the United States Department of Health, Education, and Welfare. I am very grateful to Dr. W. R. Liebenberg, Dr. S. A. Hiemstra and Dr. H. V. R. von Rahden of National Institute for Metallurgy, South Africa for their valuable help and interest and Prof. Nelson Fuson and Prof. James R. Lawson for advice and discussion.  相似文献   

10.
The governing equations for one‐dimensional consolidation of layered structured soils under time‐dependent loading are established. Using simplified k‐σ′ and mv‐σ′ models, n‐layered structured soils are transformed into (n + 1) or (n + 2)‐layered soils in which the thickness of upper and lower layers are gradually changing. The approximate solutions for the governing equations are then obtained under two types of boundary conditions, and the computer program is developed. Based on the solutions and computer program, the consolidation behavior of layered structured soils with soft interlayer is studied. It is shown that the permeability and compressibility of the soft interlayer have the greatest influences on the rate of settlement and rate of the dissipation of excess pore water pressure. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
An expression is derived for the calculation of time-integrated metamorphic fluid fluxes in two or more dimensions in rocks undergoing multivariant reactions under conditions of varying pressure, temperature and angle of flow. This calcuation requires knowledge of mineral assemblages, modes and compositions, which are obtained from isobaric T-X CO2 pseudosections constructed using the program THERMOCALC and compared with those observed in east central Vermont. THERMOCALC is capable of reproducing peak mineral assemblages, modes, compositions and the observed reaction sequences within the system KCaNaFMASCH for two kyanite grade pelitic carbonate rocks from a Barrovian style regional metamorphic terrain in east central Vermont, U.S.A. Calculation of fluid fluxes for decarbonation reactions under conditions of horizontal, layer-parallel flow produces time-integrated fluid flux figures of the order of 108 moles m−2. Allowance for possible cross-layer flow from adjacent dehydrating pelites reduces this figure significantly, with episodic cross-layer fluxes of the order of 105 moles m−2 being capable of driving the observed decarbonation. Chlorite bearing carbonate protoliths would have initially dehydrated with increasing temperature, a process requiring down-temperature fluid flow to produce the assemblages currently observed. Received: 28 January 1998 / Accepted: 20 September 1998  相似文献   

12.
Worldwide, the ammonoid genus Prolobites is only known from a few localities, and from these fossil beds almost all of the specimens are adults as shown by the presence of a terminal growth stage. This is in marked contrast to the co-occurring ammonoid genera such as Sporadoceras, Prionoceras, and Platyclymenia. Size distribution of specimens of Prolobites from three studied localities show that, unlike in the co-occurring ammonoid species, most of the material belongs to adult individuals. The morphometric analysis of Prolobites delphinus (Sandberger & Sandberger 1851) demonstrates the intraspecific variability including variants with elliptical coiling and that dimorphism is not detectable. The Prolobites material shows close resemblance to spawning populations of Recent coleoids such as the squid Todarodes filippovae Adam 1975. Possible mass spawning events are discussed in the context of the size distribution and limited geographic range of Prolobites. Finally, the potential fecundity and brooding behaviour of Prolobites is hypothesized using the examples of post spawning egg care in Recent coleoids.  相似文献   

13.
Mathematical models in which a response variableY is calculated, usually via a computer program, as a function of input variablesX 1 ,X 2, ...,X k are encountered frequently in earth sciences literature. In many cases, uncertainty in the knowledge of the correct values of the input variables exists, leading to uncertainty in the correct value of the response. Sensitivity analysis procedures can be used to identify which input variable uncertainties contribute most to uncertainty in the response variable.This paper presents the technique of Latin hypercube sampling, a structured, formal sampling process used in the sensitivity analysis procedure. Output resulting from the sample is analyzed using stepwise regression analysis, leading to identification of key input variables. Future data gathering activities can then be done efficiently, focusing on these variables. The technique is applied to a model, developed by Sudicky and Frind, which represents the flow of a contaminant through a porous media.  相似文献   

14.
Structural formulas were calculated for 8 analysed coexisting biotite-muscovitepairs from granitic rocks. Characteristic components of these structural formulas were plotted against the unit cell dimensions of these micas.In accordance with the results of Gower (1957) the substitution of OH– by F– in trioctahedral micas was found to reduce c 0 · . However, in contrast to his statements, octahedral alumina was found to reduce c 0 · sin also and to an even larger extent than fluorine. This observation is in agreement with the commonly encountered compacting of the mica structure through replacement of 3 large cations (Fe2+, Mg2+, Mn2+) by two smaller ones (Al3+, Fe3+).Concerning b 0 the combined amounts of octahedral Al and tetrahedral Si cause a reduction of this value, which means indirectly that tetrahedral Al alone would increase b 0.Reductions of b 0 and c 0 · sin by Al in synthetic micas were also found by Crowley and Roy (1964) and Seifert (1966) for the substitution Mg + Si by two Al in trioctahedral micas.In an earlier paper the author (Müller, 1966) has already shown with the same mica samples that the substitutions of M2+ by Al3+ and of OH– by F– also have the strongest effects of all substitutions on the refractive indices, densities, and specific refractive energies of these micas. Therefore it is evident that the latter effects as well as the changes of lattice constants described in this paper are interrelated.

Mein Dank gilt den Herren Dr.W. Harre und Dr. H. Gundlach, Bundesanstalt für Bodenforschung, Hannover, für die Ausführung der chemischen Glimmeranalysen, sowie der Deutschen Forschungsgemeinschaft, Bad Godesberg, für ihre finanzielle Beihilfe. Herrn Dr. F. Seifert, Kiel, danke ich für zahlreiche sachliche Diskussionen und Hinweise und für die Überlassung seines Algol-Rechenprogramms, mit welchem 4 der 16 Strukturformeln elektronisch berechnet wurden. Herrn Prof. Dr. F. Liebau, Kiel, verdanke ich einige freundliche Ratschläge.  相似文献   

15.
The autometamorphic transformation of iron-rich biotite to chlorite and muscovite with the by-products hematite, ilmenite, sphene, and rutile has been studied in thin-sections of about 50 granitic rocks of Austria and Bavaria.From 19 granitic rock samples the magmatic biotites, their secondary chlorites, and muscovites were separated, purified by hand-picking, and investigated by optical, x-ray, and chemical methods. The silicatic products of biotite transformation were found to be iron-rich chlorites and iron-poor muscovites.The essentiall process of biotite alteration to chlorite is based in the emigration of 9,5–12, 2 Eq.wt.% Si and nearly the complete alcali. This leak is only compensated by the importation of 23,3–27,6 Eq.wt.% H2O+.The chemical changes of biotite alteration to muscovite are characterized by the emigration of 15–20 Eq.wt.% Fe, Mg, Ti and the importation of 9,3–14,2 Al, 4,6–7,1 Si, and 1,3–4,3 Eq.wt% H2O+.Owing to the transformation of biotite unit cell dimensions considerable changes. As a result of biotite replacement by chlorite c 0·sin increases about 40%. a 0 and b 0 only extends for 0,8%.In comparison with these facts of chloritisation biotite transformation to muscovite was found to reduce a 0 and b 0 (–2,6%) much stronger than c 0·sin (–0,7%).Modal analysis data of retrograde alterations of biotite and feldspar in the granites were connected with the observed and calculated values of main element changing. In the granitic samples about 50% of iron and titanium have been converted from silicatic into oxidic minerals like hematite, ilmenite, sphene, and rutile during the biotite transformation.59–92% of H2O+ in these rocks fall to the share of secondary sheet silicate forming during the latest phases of granite crystallisation.The balance account of the various chemical reactions shows for the closed system a deficit of H2O and Al, and a surplus of Fe, Ti, and F. The deficit or surplus of Si, Mg, Mn, Ca, Na, K, and Li in the samples is very different and dependent on the values of biotite chloritisation, feldspar sericitisation, and so forth.At the present time quantitative control of the complete chemical exchanges during the automorphism of these granites is not possible, because the quartz-feldspar-reactions have not yet been investigated.

Für Anregungen, Diskussionen, sachliche Hilfen und förderndes Interesse bin ich den Herren Prof. Dr. C. W. Correns, Göttingen; Dr. H. Fesser, Hannover; Prof. Dr. H. R. v. Gaertner, Hannover; Dr. H. Gundlach, Hannover; Dipl.-Min. U. Haack, Göttingen; Dr. W. Harre, Hannover; Prof. Dr. F. Karl, Kiel; Prof. Dr. R. Mannkopff, Göttingen; Dr. C. Savelli, Göttingen; Prof. Dr. W. Schreyer, Kiel; Dr. F. Seifert; Kiel; Dipl.-Phys. W. Stahl, Hannover; Prof. Dr. K. H. Wedepohl, Göttingen, und Prof. Dr. H. G. F. Winkler, Göttingen, zu großem Dank verpflichtet.

Folgende Institutionen haben meine Arbeit durch die Erlaubnis der Benutzung von wissenschaftlichen Geräten und durch sachliche und finanzielle Mittel in dankenswerter Weise unterstützt: Bundesanstalt für Bodenforschung, Hannover, Deutsehe Forschungsgemeinschaft, Bad Godesberg, Geochemisches Institut der Universität, Göttingen, und das Mineralogisch-Petrographische Institut der Universität, Kiel.

Meinen Assistentinnen Frl. G. Klaetsch, Frl. B. Köhler und Frau H. Grapp bin ich für ihre große Geduld und ihren ausdauernden Fleiß bei der jahrelangen mühsamen Trennung und Reinigung der Mineralphasen von Herzen dankbar.  相似文献   

16.
Given a set of nondirectional orientation data (fold axes, lineations, dip and dip direction of bedding, universal stage readings of crystallographic axes, etc.),the best-fit line (point maximum),plane (great circle),or cone (small circle)can be determined by minimizing the sum of the squares of the angular residuals using a simplex convergence technique. Stereoplots of the angular deviation over the complete lower hemisphere for these distributions may also be generated when consideration of the constraint on the best-fit position is important; for example in comparing different data sets of the same structural element. The routines are available as a FORTRAN coded computer program.  相似文献   

17.
This article reviews the current state-of-the-art and future prospects of the microwave techniques for remote sensing of the earth’s atmosphere and ocean. Geophysical parameters and their relationship with measured thermal microwave radiation is established through radiative transfer processes. The atmospheric temperature profile obtained from microwave sounding unit (msu) onboardtiros-N series of satellites is operational and is used for numerical weather prediction. The demonstrated applications of scanning multichannel microwave radiometer (smmr) onboard most recent and advancedseasat satellite are highlighted.The capability ofseasat active sensors for monitoring ocean parameters have also been indicated. Feasible applications of microwave techniquese.g. moisture profile with advanced moisture sounder (amsu), and surface pressure from multifrequency active microwave pressure sounder (mps) are also described. Finally the recent and advanced microwave limb sounding (mls) technique and its applications to upper atmospheric research has been reviewed.  相似文献   

18.
In the Ultevis District, Northern Sweden, viridine occurs in a potassium rich, microcline-bearing leptite together with quartz, plagioclase, phlogopite, opaques, and a retrogradely formed muscovite. The formation of viridine in this rock may be described by a dealkalization process of microcline, in which opaque minerals are involved. A diffusion of K+ and H2O out of the centres of viridine formation and of H+ into these localities, which is a prerequisite of such type of reaction, may have been favoured by a contemporaneous migmatization of the rock, since the granite-like melts can be regarded as sinks for potassium and water. The following decomposition of viridine is initiated by the reverse reaction. Texturally this is indicated by small microcline seams along the contacts between viridine and quartz grains. The final alkalization of the viridine-quartz assemblage to form muscovite reflects increasing K+/H+-ratios and H2O-contents of the vapor phase and/or decreasing temperatures. The potassium and water amounts necessary for the viridine decomposition reactions may have been generated by the cooling of the granitic liquids. An intergrowth of sillimanite and the muscovite can be described by a degenerated reaction. It can be interpreted as giving way to an equilibration of the alumosilicates und the actual metamorphic conditions, that is here P, T, , a k +, a h + and a Mn 3+.The viridine investigated has the lowest Mn-contents recorded so far for andalusite-type minerals with viridine optics (1.3–2.2 mol-% Mn2SiO5-component). Since no andalusite with lower Mn-contents occurs in the rock and since no other Al2SiO5-phase formed at this metamorphic stage it may be assumed that the incorporation of manganese stabilizes the andalusite structure under the P-, T-, –, a k +-, a h +- and a Mn 3+-conditions verified in this particular leptite.The temperature of viridine formation is estimated to be about 600 ° C, the decomposition of viridine +quartz into the muscovite-sillimanite assemblage may have happened between 650–500 ° C at 6–2.5 kb.  相似文献   

19.
Zusammenfassung Im Rahmen neuerer Untersuchungen an Mineralen der Olivingruppe wurde die Struktur von Monticellit (MgCaSiO4) neu bestimmt und verfeinert. Die im Jahre 1927 vonBrown undWest bestimmte Struktur ließ sich im wesentlichen bestätigen. In 13 Verfeinerungszyklen, nach der Methode der kleinsten Quadrate auf einer Rechenanlage des Typs IBM 7094 durchgeführt, ließ sich der R-Faktor von 0,439 auf 0,068 für 345 hkl-Reflexe herabdrücken.Ein Vergleich der Atomabstände und Winkel mit bereits bekannten Daten des Olivins und Fayalits zeigte eine bemerkenswerte Übereinstimmung.
Summary As part of a detailed study of minerals of the olivine group the structure of monticellit (MgCaSiO4) was redetermined and refined. The structure, as given byBrown andWest (1927) was found to be fundamentally correct. Thirteen cycles of leastsquares refinement on the IBM 7094 computer reduced the disagreement factor, R, for 345 hkl reflections from an initial value of 0.439 to a final value of 0.068.A comparison of atomic distances and bond angles with previously determined data of olivine and fayalite showed remarkable agreement.

Herrn Professor Dr.F. Machatschki zum 70. Geburtstag gewidmet.  相似文献   

20.
Dinosaur skin impressions are rare in the Upper Jurassic Morrison Formation, but different sites on the Howe Ranch in Wyoming (USA), comprising specimens from diplodocid, camarasaurid, allosaurid and stegosaurian dinosaurs, have proven to be a treasure-trove for these soft-tissue remains. Here we describe stegosaurian skin impressions from North America for the first time, as well as the first case of preservation of an impression of the integument that covered the dorsal plates of stegosaurian dinosaurs in life. Both have been found closely associated with bones of a specimen of the stegosaurian Hesperosaurus mjosi Carpenter, Miles and Cloward 2001. The scales of the skin impression of H. mjosi are very similar in shape and arrangement to those of Gigantspinosaurus sichuanensis Ouyang 1992, the only other stegosaurian dinosaur from which skin impressions have been described. Both taxa show a ground pattern of small polygonal scales, which in some places is interrupted by larger oval tubercles surrounded by the small scales, resulting in rosette-like structures. The respective phylogenetic positions of G. sichuanensis as a basal stegosaurian and H. mjosi as a derived form suggest that most stegosaurians had very similar skin structures, which also match the most common textures known in dinosaurs. The integumentary impression from the dorsal plate brings new data to the long-lasting debate concerning the function of dorsal plates in stegosaurian dinosaurs. Unlike usual dinosaur skin impressions, the integument covering the dorsal plates does not show any scale-like texture. It is smooth with long and parallel, shallow grooves, a structure that is interpreted as representing a keratinous covering of the plates. The presence of such a keratinous covering has affects on all the existing theories concerning the function of stegosaurian plates, including defense, thermoregulation, and display, but does not permit to rule out any of them.  相似文献   

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