A review of: “The physics of the earth's core: An introduction”

Abstract

By Paul Melchior. Pergamon Press, 1986. vi + 256 pp. $19.95 (ISBN 0080326064).     

Comment on Pisarenko et al., “Characterization of the Tail of the Distribution of Earthquake Magnitudes by Combining the GEV and GPD Descriptions of Extreme Value Theory”

In this short note, I comment on the research of Pisarenko et al. (Pure Appl. Geophys 171:1599–1624, 2014) regarding the extreme value theory and statistics in the case of earthquake magnitudes. The link between the generalized extreme value distribution (GEVD) as an asymptotic model for the block maxima of a random variable and the generalized Pareto distribution (GPD) as a model for the peaks over threshold (POT) of the same random variable is presented more clearly. Inappropriately, Pisarenkoet al. (Pure Appl. Geophys 171:1599–1624, 2014) have neglected to note that the approximations by GEVD and GPD work only asymptotically in most cases. This is particularly the case with truncated exponential distribution (TED), a popular distribution model for earthquake magnitudes. I explain why the classical models and methods of the extreme value theory and statistics do not work well for truncated exponential distributions. Consequently, these classical methods should be used for the estimation of the upper bound magnitude and corresponding parameters. Furthermore, I comment on various issues of statistical inference in Pisarenkoet al. and propose alternatives. I argue why GPD and GEVD would work for various types of stochastic earthquake processes in time, and not only for the homogeneous (stationary) Poisson process as assumed by Pisarenko et al. (Pure Appl. Geophys 171:1599–1624, 2014). The crucial point of earthquake magnitudes is the poor convergence of their tail distribution to the GPD, and not the earthquake process over time.     

A review of: “Magnetospheric plasma physics”

Abstract

Edited by A. Nishida. D. Reidel Publishing Company, xii+348 pp. Cloth Dfl. 130,-/US $49.50 (ISBN 0 8130 0601 5) 1982.     

A review of: “Quantitative aspects of magnetospheric physics”

Abstract

by L. R. Lyons and D. J. Williams. D. Reidel Publishing Co., .231 pages (ISBN 90-2771663-3). Price 130.00 DFL (1984).     

Professor Yu.D. Kalinin: The founder and first Editor-in-Chief of the Journal “Geomagnetism and Aeronomy” (Towards the Centenary of the Birth and to the 50th Anniversary of the Foundation of This Journal)

Information is given regarding the life, work, scientific research, and organizational activities of Professor Yu.D. Kalinin, the founder and the first editor-in-chief of the journal “Geomagnetism and Aeronomy.” The paper is devoted to the centenary of the birth of Yu.D. Kalinin and to the 50th anniversary of the beginning of the publication of the journal.     

Comment on “A note on the free-surface effect on the topographicaily induced vorticity field in a homogeneous flow” by lee-or merkine

Abstract

MASS LOSS AND EVOLUTION OF O-TYPE STARS. I.A.U. Symposium No. 83. Edited by P. S. Conti and C. W. H. de Loore. Reidel, Dordrecht. (ISBN 90-277-0989-0 pbk) 1979. Price U.S. $31.50.

A MATHEMATICAL INTRODUCTION TO FLUID MECHANICS by A. J. Chorin &; J. E. Marsden, 205 pages, paperback, Springer Verlag. (ISBN 0-387-90406-9 and ISBN 3-540-90406-9) 1979. Price: DM 29—US $16.00.     

Comment on the paper “The Relationship between Multifractal and Entropy Properties of Seismic Noise in Kamchatka and Irregularity of the Earth’s Rotation” by A.A. Lyubushin,G.N. Kopylova,and Yu.K. Serafimova

Izvestiya, Physics of the Solid Earth - Abstract—In my comment on the paper by A.A. Lyubushin, G.N. Kopylova, and Yu.K. Serafimova, I focus on the problem of legitimacy of seismological data...     

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.     

The newest observational evidence on asymmetrical deformation of the Earth

IntroductionWhat is the shape of the Earth? Does it change continuously? It is a scientific question since the ancient times and is still being observed and explored at present. In 250 BC, Greek scholar Eratosthene supposed the shape of the Earth to be spherical according to the observations to the Sun and estimated the perimeter of the Earth to be 4 000 km (King-Hele, 1976) according to the camel-walking distance. Until the 16th century, the Earth was considered to be a very symmetrical …     

The Program Application on the Relative Method of Fuzzy Mathematics

The method of fuzzy mathematics for simultaneous assessment of time and intensity of earthquake hazards has been studied.This method is based on fundamental statistical indices of regional seismicity.Applying the retrieval method of fuzzy information,we can classify the time and intensity into several intervals and classes of seismic activity,then the possible time interval of large earthquakes with magnitude of M≥Ms can be estimated in a given region.Based on the preceding idea,an FRPP program is constructed.For the automatic data processing when this method is used,it is very important to design the statistical process of each index decomposition so that the program could be fit to a different sample discussed.There are some functions in the FRPP program.The man-made impact on results is reduced to the minimum as far as possible.Computation time is saved.There is a menu on which time interval,index,intensity class,and output data all can be selected.The catalog input that can be displayed on the scre     

The Influence of Earth Temperature on the Dynamic Characteristics of Frozen Soil and the Parameters of Ground Motion on Sites of Permafrost

Earth temperature is one of the most important factors influencing the mechanical properties of frozen soil. Based on the field investigation of the characteristics of ground deformation and ground failure caused by the Ms8.1 earthquake in the west of the Kuniun Mountain Pass,China, the influence of temperature on the dynamic constitutive relationship, dynamic elastic modulus, damping ratio and dynamic strength of frozen soil was quantitatively studied by means of the dynamic triaxial test. Moreover, the characteristics of ground motion on a permafrost site under different temperatures were analyzed for the four profiles of permafrost along the Qinghai-Xizang (Tibet) Railway using the time histories of ground motionacceleration with 3 exceedance probabilities of the Kunlun Mountains area. The influences of temperature on the seismic displacement, velocity, acceleration and response spectrum on permafrost ground were studied quantitatively. A scientific basis was presented for earthquake disaster mitigation for engineering foundations, highways and underground engineering in permafrost areas.     

Earthquake Probability of the “Seismic Gap” on the Longmenshan Fault

Using the layered viscoelastic medium model, this paper calculated the coulomb stress loading effect on the Lushan epicenter generated by the Wenchuan earthquake. Then combined with the rate-state friction law proposed by Dieterich J. (1994), we obtain the probability of an M_W ≥ 6.0 earthquake occurring in the vicinity of Lushan. The results show that the probability of M_W ≥ 6.0 earthquake of the Lushan region in 2013 is up to 18%, indicating that the stress disturbance caused by the Wenchuan earthquake accelerated the Lushan earthquake. This paper also calculates the coulomb stress accumulation on the "seismic gap" generated by the two earthquakes of Wenchuan and Lushan, and combined with the background seismicity, gives the M_W>6.0 earthquake probability of the "seismic gap". Although there may be a certain error in the results because of the Dayi earthquake, selection of the medium model parameters and background seismicity, the seismic probability of the "seismic gap" is increasing. Thus, we think destructive earthquakes are still likely to occur in the "seismic gap".     

Reply to “Comments on the paper “A crustal-upper mantle model for southeastern Sicily (Italy) from the integration of petrologic and geophysical data” by ”

We reply to the comments of Beccaluva et al. (2013) on the paper “A crustal-upper mantle model for southeastern Sicily (Italy) from the integration of petrologic and geophysical data” by Manuella et al. (2013). We entirely reject their speculative comments and strongly confirm our viewpoint on the aged oceanic nature of the lithospheric basement of southeastern Sicily and its offshore area.     

MHD structure of interplanetary disturbances observed near the earth during the solar-terrestrial storm of November 7–13, 2004

This paper considers the MHD structure and configuration of near-Earth interplanetary disturbances during the heliospheric extrastorm of November 2004, taking into account the effect of the IMF sector structure and using the measurements of near-Earth satellites. During three successive disturbance intervals, the Earth entered, remained and left a relative narrow positive sector with flare-active region 10696, which generated a series of shocks and an active transequatorial filament. It has been indicated that the MHD structure and configuration of near-Earth disturbances substantially and specifically (for each position) depend on the IMF sector structure and interactions between shocks and sector boundaries, filaments, and magnetic clouds in these three different positions. Specifically, this manifested itself in multiple crossings of sector boundaries and considerable deformations of magnetic clouds. It has been indicated that the models of circular clouds are applied with limitations under the considered conditions.     

The evolution of sub-mesoscale,coherent vortices on the β-plane

Abstract

An investigation is made of the evolution of small-scale, axisymmetric vortices in a stratified fluid with spatially variable Coriolis parameter. The criteria for smadness are a horizontal scale less than or equal to the first internal radius of deformation and a vertical scale less than or equal to that of the ambient stratification. These circumstances match those of Sub-mesoscale, Coherent Vortices frequently observed in the oceans. The dynamical model is the balance equations, which include various effects of finite Rossby number. The principal topics are the regime of nearly uniform propagation, the development of an equilibrium ratio of vertical and horizontal scales (i.e., Burger number selection), and the occurrence of various types of instability for vortices with extremes in amplitude or shape.     

The contribution of “silent” faults to the seismic hazard of the northern Adriatic Sea

There is a difference in the seismogenic zonation used for seismic hazard assessment of ordinary buildings and that considered for critical facilities, because different levels of exceedence probability are taken into account. Consequently, in the second case tectonic structures with a low, or very low, likelihood of activation also need attention. The key factor in seismogenic zonation for seismic hazard assessment is investigated here considering some seismically undocumented faults of the northern Adriatic Sea area. Seismic hazard is evaluated for two constructions located around Trieste and close to the sea: an ordinary building and a critical facility. The results clearly show that the two constructions should be designed with quite a different level of expected ground motion in mind. Part of the difference, in the computation of the critical facility, is determined by the introduction of some faults without documented seismicity.