Showing papers on "Deformation (meteorology) published in 1984"

The experimental foundations of solid mechanics

Abstract: I. Introduction.- II. Small deformation nonlinearity.- III. Small deformation: The linear approximation.- IV. Finite Deformation.- Namenverzeichnis. - Author Index.- Sachverzeichnis (Deutsch-Englisch).- Subject Index (English-German).

Fault-related rocks: Suggestions for terminology

Abstract: Many traditional terms for fault-related rocks have undergone recent dynamic metamorphism under high-pressure discussions by various groups of specialists. A generally acceptable simplified framework encompassing these and associated structural terms is now needed for many geologic, engineering, and legal purposes. Such a framework is proposed here, focusing on a rate-of-strain versus rate-of-recovery diagram and relating this framework to the products of brittle and ductile deformation along faults.

The earthquake deformation cycle at the Nankai Trough, southwest Japan

Abstract: Geodetic measurements made landward of the Nankai Trough, site of great subduction zone thrust earthquakes in 1854 and 1946, provide a uniquely detailed picture of the strain buildup process, supply constraints on the mechanism of strain accumulation, and allow for improved estimates of earthquake recurrence. Provided the two most recent movement cycles are similar, the observations, dating from about 1890, may be used to reconstruct a single complete deformation cycle (coseismic strain release, postseismic transients, interseismic strain accumulation). Very complete leveling and tidal gage data indicate that postseismic deformation extends more than 300 km inland from the plate boundary, persists for at least 30 years, and shows a clear tendency to become longer wavelength with increasing time. The transient movements have two timescales. The first, of about a year or less, corresponds to deformation, largely uplift, concentrated close to the coseismic fault, and is most easily explained by aseismic slip or very localized deformation downdip of the earthquake rupture plane. The second, longer, timescale is associated with a diffusion-like spread of the deformation further landward, an effect qualitatively similar to that first predicted by Elsasser to be an expected consequence of faulting in an elastic plate overlying a viscoelastic asthenosphere. Cumulative uplift since 1890 correlates well with the distribution of uplifted marine terraces, although average post-1890 tilt rates exceed late Quaternary and Holocene averages by at least a factor of three. Because of the nonlinearity of strain buildup and the significant permanent deformation, simple recurrence calculations typically overestimate the true interval between great earthquakes by a factor of 2 to a factor of 3. Strict application of the time-predictable model, assumed correct, overcomes these difficulties provided the cumulative transient deformation and the proportion of permanent deformation per cycle can be estimated.

Computer simulation of a two-dimensional soap froth II. Analysis of results

Abstract: Further results are presented for a simulated two-dimensional soap froth. These include the dependence of the evolution of the system on the choice of initial conditions, and its mechanical properties. The results are set in the context of recent ideas on grain growth, superplastic deformation and the properties of emulsions.

Systematics of Nuclear Deformations

Abstract: The microscopic-macroscopic method Nilsson and Strutinsky is used to calculate potential energy surfaces with the modified oscillator potential for both neutron deficient, beta-stable and neutron excess nuclei. These calculations reiterate the previous suggestion that in the medium mass nuclei with A ~ 70-140 moderate deformation results from the cooperative formation of a potential minimum from the anti-shell effect at zero deformation and the rising potential energy of the liquid drop at positive deformation. Regions of deformation suggested by these calculations are for example the neutron excess 38Sr and 40Zr, the neutron deficient 56Ba and rare earth nuclei, and a region of more transitional character, involving the neutron deficient nuclei with proton numbers Z 36-38. The experimental situations are briefly reviewed for these nuclear regions and the calculations used as a guide to suggest additional experiments. Other regions of nuclear deformation are also discussed briefly.

The study of model polydiacetylene/epoxy composites: Part 1 The axial strain in the fibre

Abstract: Le compose modele est soumis a une deformation d'etirage dans une direction parallele a la fibre. On determine la deformation tout au long de la fibre par spectroscopie Raman et de la matrice par les techniques classiques

Neotectonic deformation patterns in the convex-northwards arc of the North Anatolian fault zone

Abstract: Summary The convex-northwards arc of the North Anatolian fault zone between Çerkeş and Erbaa contains structures and landforms permitting right-lateral displacements for several time intervals to be estimated. Within the Pontus Formation (Late Miocene-Early Pleistocene) in basins along the fault zone, an unconformity, representing a time interval from the latest Tortonian to the earliest Pliocene, is interpreted as marking the transformation of the structure from a broad shear zone to a narrow fault belt. Although the amount of displacement during the shear zone phase is unknown the offset of a sedimentary facies boundary in the Lower Pontus Formation of the Havza-Ladik basin demonstrates that since the latest Tortonian there has been 25 km of right-lateral slip. The offset of valleys and ridges suggests that there has been 8 km of Quaternary displacement, about 2 km of it in the late Quaternary and at least 500 m during the Holocene. Structures in the Pontus Formation indicate that the early history of the western Neogene basins was influenced by regional compression and that the later histories of all basins were dominated by strike-slip displacements. The main active trace is discontinuous, the 2 km-wide belt containing subordinate en échelon faults whose geometry is consistent with development during right-lateral shear.

Numerical solution of free-boundary problems in fluid mechanics. Part 3. Bubble deformation in an axisymmetric straining flow

Abstract: We consider the deformation of a bubble in a uniaxial extensional flow for Reynolds numbers in the range 0.1 [less-than-or-eq, slant] R [less-than-or-eq, slant] 100. The computations show that the bubble bursts at a relatively early stage of deformation for R [gt-or-equal, slanted] O(10), never reaching the highly elongated shapes observed and predicted at lower Reynolds numbers. We also compute the deformation of the bubble under the assumption of potential flow, and conclude that the potential-flow solution provides a good approximation to the real flow in this case for R [gt-or-equal, slanted] O(100).

Plastic compression of spheres

Abstract: An experimental investigation is reported of the compression of metal spheres between smooth parallel platens. Measurements have been made of the mean contact pressure P as a function of the radius of the contact area a. For work-hardened metals, P was found to increase to a maximum value of 0·7 to 0·8 times the Vickers hardness of the sphere material, at a value of a/R ≃ 0·20 to 0·28, where R is the radius of the sphere before deformation. The contact pressure then declined steadily with increasing a/R. Annealed metals showed oither no maximum in pressure, or a very broad peak. Qualitative explanations of these results are given by analogy with other deformation geometries.

Methods for manufacture of valve flaps for cardiac valve prostheses

Abstract: Sheets of incompletely fixed biological tissue comprising portions for defining valve flaps of a cardiac valve prosthesis are mounted on forming means which can separate in a substantially fluid-tight manner the opposite faces of such portions. These opposite faces are subjected to a fluid pressure difference which produces deformation of the portions towards a conformation substantially identical with the conformation of the valve flaps when mounted in the prosthesis. The biological tissue is finally fixed while the portions defining the valve flaps of the prosthesis are maintained in the said conformation. The sheets of biological tissue are then separated from the forming means to be subsequently mounted in the frame of the prosthesis.

A Nonlinear Theory for Elastic Plates With Application to Characterizing Paper Properties

Abstract: On developpe une theorie des plaques minces physiquement et cinematiquement non lineaire. On l'utilise pour caracteriser le comportement de materiaux elastiques pour des deformations arbitraires en etirement et flexion. On introduit un concept de deformation effective pour simplifier la theorie et on l'applique a la caracterisation du papier