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9,700
Earthquake source parameters and fault kinematics in the Eastern California Shear Zone
physics.geo-ph
Based on waveform data from a profile of aftershocks following the north-south trace of the June 28, 1992 Landers rupture across the Mojave desert, we construct a new velocity model for the Mojave region which features a thin, slow crust. Using this model, we obtain source parameters, including depth and duration, for ...
physics
9,701
An Automatic Method for Determination of Lg Arrival Times Using Wavelet Transforms
physics.geo-ph
The regional phase Lg is used to estimate location and magnitude for sources closer than 1500 km. The complexity of Lg waveforms makes it difficult to consistently determine Lg arrival time, thus affecting source location with a single station or array. This study tests an automatic method for timing Lg arrivals using ...
physics
9,702
A brief History of the Earth
physics.geo-ph
The possibility of an increasing gravitational constant $G$ and its implication on the Earth's history are discussed. The model is consistent with geophysical and astronomical data. The number of days in early epochs predicted by the model is in agreement with those obtained from fossil corals. The model predicts that ...
physics
9,703
GIST: A tool for Global Ionospheric Tomography using GPS ground and LEO d ata and sources of opportunity with applications in instrument calibration
physics.geo-ph
Ionospheric tomography using GPS data has been reported in the literature and even the application to radar altimeter calibration was succesfully carried out in a recent work. We here present a new software tool, called Global Ionospheric Stochastic Tomography software (GIST), and its powerful capability for ingesting ...
physics
9,704
Some Wave-Related, Heavy Mineral Placer Deposits
physics.geo-ph
Examples of heavy mineral placer deposits are presented in which wave reflection, refraction, diffraction and resonance would appear to have played a major concentrating role. Their geometry is compared with the computer generated patterns predicted for the reflection, refraction and diffraction of surface waves moving...
physics
9,705
Seismic Wave Recording by 2S-Seismographs
physics.geo-ph
Researchers of seismic waves may construct a new seismographic recording adding one seismometer to each component of a conventional seismic station. The two identical conventional seismometers are set up in position of perpendicular and are connected in parallel feeding one recording device (digital or analog). This us...
physics
9,706
Geometry of River Networks I: Scaling, Fluctuations, and Deviations
physics.geo-ph
This article is the first in a series of three papers investigating the detailed geometry of river networks. Large-scale river networks mark an important class of two-dimensional branching networks, being not only of intrinsic interest but also a pervasive natural phenomenon. In the description of river network structu...
physics
9,707
Geometry of River Networks II: Distributions of Component Size and Number
physics.geo-ph
The structure of a river network may be seen as a discrete set of nested sub-networks built out of individual stream segments. These network components are assigned an integral stream order via a hierarchical and discrete ordering method. Exponential relationships, known as Horton's laws, between stream order and ensem...
physics
9,708
Geometry of River Networks III: Characterization of Component Connectivity
physics.geo-ph
River networks serve as a paradigmatic example of all branching networks. Essential to understanding the overall structure of river networks is a knowledge of their detailed architecture. Here we show that sub-branches are distributed exponentially in size and that they are randomly distributed in space, thereby comple...
physics
9,709
Instantaneous response of the ionosphere to a sudden commencement of the strong magnetic storm of April 6, 2000
physics.geo-ph
We developed a new technology for global detection of atmospheric disturbances, on the basis of phase measurements of the total electron content (TEC) using an international GPS networks. Temporal dependencies of TEC are obtained for a set of spaced receivers of the GPS network simultaneously for the entire set of visi...
physics
9,710
Effects of the August 11, 1999 total solar eclipse as deduced from total electron content measurements at the GPS network
physics.geo-ph
We present the results derived from measuring fundamental parameters of the ionospheric response to the August 11, 1999 total solar eclipse. Our study is based on using the data from about 70 GPS stations located in the neighbourhood of the eclipse totality phase in Europe. The eclipse period was characterized by a low...
physics
9,711
The GPS global detection of the ionospheric response to solar flares
physics.geo-ph
This author suggests the concept of a new technology for global detection (GLOBDET) of atmospheric disturbances of natural and technogenic origin, on the basis of phase measurements of the total electron content (TEC) in the ionosphere using an international GPS network. Temporal dependencies of TEC are obtained for a ...
physics
9,712
Ionospheric effects of the solar flares of September 23, 1998 and July 29, 1999 as deduced from global GPS network data
physics.geo-ph
This paper presents data from first GPS measurements of global response of the ionosphere to solar flares of September 23, 1998 and July 29, 1999. The analysis used novel technology of a global detection of ionospheric effects from solar flares (GLOBDET) as developed by one of the authors (Afraimovich E. L.). The essen...
physics
9,713
The shock-acoustic waves generated by earthquakes
physics.geo-ph
We investigate the form and dynamics of shock-acoustic waves generated by earthquakes. We use the method for detecting and locating the sources of ionospheric impulsive disturbances, based on using data from a global network of receivers of the GPS navigation system and requiring no a priori information about the place...
physics
9,714
The use of GPS-arrays in detecting shock-acoustic waves generated during rocket launchings
physics.geo-ph
This paper is concerned with the form and dynamics of shock-acoustic waves (SAW) generated during rocket launchings. We have developed a method for determining SAW parameters (including angular characteristics of the wave vector, and the SAW phase velocity, as well as the direction towards the source) using GPS-arrays ...
physics
9,715
Magnetospheric disturbances, and the GPS operation
physics.geo-ph
We have investigated a dependence of the relative density of phase slips in the GPS navigation system on the disturbance level of the Earth's magnetosphere. The study is based on using Internet-available selected data from the global GPS network, with the simultaneously handled number of receiving stations ranging from...
physics
9,716
Pressure-volume-temperature equation of state of MgSiO3 perovskite from molecular dynamics and constraints on lower mantle composition
physics.geo-ph
The composition of the lower mantle can be investigated by examining densities and seismic velocities of compositional models as functions of depth. In order to do this it is necessary to know the volumes and thermoelastic properties of the compositional constituents under lower mantle conditions. We determined the the...
physics
9,717
Aircraft Hazard related to gas emission from the Earth
physics.geo-ph
I think it important that pilots, the aircraft industry, air safety staff, accident investigators, should all be aware of the possibility of the hazard described in the accompanying article, and also that research shold be directed to establish the severity of this hazard, and find ways of diminishing the risk.
physics
9,718
Geomagnetic control of the spectrum of traveling ionospheric disturbances based on data from a global GPS network
physics.geo-ph
In this paper an attempt is made to verify the hypothesis on the role of geomagnetic disturbances as a factor determining the intensity of traveling ionospheric disturbances (TIDs). To improve the statistical validity of the data, we have used the based on the new GLOBDET technology method involving a global spatial av...
physics
9,719
Analytic tomography of the mantle in a spherically Earth. The technique MZY
physics.geo-ph
An explicit expression for P-wave velocity is proposed to develop a novel tomographic technique in a spherically symmetric model of the Earth (MZY). The distribution of the P velocity structure in the mantle is determined using only 34 P- and 2 PcP-observed traveltimes. By applying a non-linear inversion, the P-residua...
physics
9,720
Energy Distribution in Earthquakes: A Non-Extensive Approach
physics.geo-ph
By using the maximum entropy principle with Tsallis entropy and under the assumption that the gouge plays an active role in the triggering of earthquakes, we obtain a functional dependence for energy distribution function for earthquakes which fits very well with observations in the region of small energies. This distr...
physics
9,721
Radio and optical observations of large-scale traveling ionospheric disturbances during a strong geomagnetic storm of 6-8 April 2000
physics.geo-ph
Basic properties of the mid-latitude large-scale traveling ionospheric disturbances (LS TIDs) during the maximum phase of a strong magnetic storm of 6-8 April 2000 are shown. Total electron content (TEC) variations were studied by using data from GPS receivers located in Russia and Central Asia. The nightglow response ...
physics
9,722
Ionospheric manifestations of geomagnetic pulsations at high latitudes
physics.geo-ph
In this paper the interrelation between geomagnetic pulsations and variations in frequency Doppler shift (Fd) of the ionosphere-reflected radio signal is under investigation. The experiment on simultaneous recording of Fd variations and geomagnetic pulsations was organised at high latitude station in Norilsk (geomagnet...
physics
9,723
Inhomogeneous structure of the high-latitude ionosphere as observed at Norilsk
physics.geo-ph
In March and August/September 1995, February 1996, and in March-April 1998, observations of the inhomogeneous structure of the high-latitude ionosphere were carried out at Norilsk (geomagnetic latitude and longitude are 64.2 N and 160.4 E, and L=5.2). Small-scale irregularities (with the lifetime of several seconds,and...
physics
9,724
Enhacement in the dymanic response of a viscoelastic fluid flowing through a longitudinally vibrating tube
physics.geo-ph
We analyzed effects of elasticity on the dynamics of fluids in porous media by studying a flow of a Maxwell fluid in a tube, which oscillates longitudinally and is subject to oscillatory pressure gradient. The present study investigates novelties brought about into the classic Biot's theory of propagation of elastic wa...
physics
9,725
Properties of Elastic Waves in a non-Newtonian (Maxwell) Fluid-Saturated Porous Medium
physics.geo-ph
The present study investigates novelties brought about into the classic Biot's theory of propagation of elastic waves in a fluid-saturated porous solid by inclusion of non-Newtonian effects that are important, for example, for hydrocarbons. Based on our previous results (Tsiklauri and Beresnev: 2001, Phys. Rev. E, 63, ...
physics
9,726
Magnetosphere-Ionosphere Coupling in the Region of Auroral Electrojets
physics.geo-ph
We discuss the question as to how the magnetospheric energy source feeds the ionospheric current system. It is shown that a consistent application and further development of Kennel's ideas makes it possible to successfully solve the magnetosphere-ionosphere coupling problem in regard to the formation of auroral elect...
physics
9,727
Ionospheric effects of the solar flares as deduced from global GPS network data
physics.geo-ph
Results derived from analysing the ionosphere response to faint and bright solar flares are presented. The analysis used technology of a global detection of ionospheric effects from solar flares as developed by the authors, on the basis of phase measurements of the total electron content (TEC) in the ionosphere using a...
physics
9,728
Ionospheric response to the total solar eclipse of June 21, 2001
physics.geo-ph
We discuss the measurements of the main parameters of the ionospheric response to the total solar eclipse of June 21, 2001. This study is based on using the data from three stations of the global GPS network located in the area of the totality band in Africa. This period was characterized by a low level of geomagnetic ...
physics
9,729
A case study of the mid-latitude GPS performance at nighttime during the magnetic storm of July 15, 2000
physics.geo-ph
Using the geomagnetic storm of July 15, 2000 as an example, we investigated the dependence of GPS navigation system performance on the nightside at mid-latitudes on the level of geomagnetic disturbance. The investigation was based on the data from the global GPS system available through the Internet. It was shown that ...
physics
9,730
Estimating the contribution from different ionospheric regions to the TEC response to the solar flares using data from the international GPS network
physics.geo-ph
This paper proposes a new method for estimating the contribution from different ionospheric regions to the response of total electron content variations to the solar flare which uses the effect of partial shadowing of the atmosphere by the terrestrial globe. The study uses GPS stations located near the boundary of the ...
physics
9,731
An additional planet as a model for the Pleistocene Ice Age
physics.geo-ph
We propose a model for the Pleistocene Ice Age, assuming the following scenario: Between 3 Myr and 11.5 kyr BP a Mars-sized object existed which moved in a highly eccentric orbit. Originating from this object, gas clouds with a complex dynamics reduced Earth's insolation and caused a drop in the global temperature. In ...
physics
9,732
Physical Properties of Iron in the Inner Core
physics.geo-ph
The Earth's inner core plays a vital role in the dynamics of our planet and is itself strongly exposed to dynamic processes as evidenced by a complex pattern of elastic structure. To gain deeper insight into the nature of these processes we rely on a characterization of the physical properties of the inner core which a...
physics
9,733
A correlation between Earth's inclinations and the times of the cold events recorded in Devils Hole climate data
physics.geo-ph
The calculated values of Earth's inclinations during the cold events in the 500 kyr climate record of Devils Hole show a correlation: they cluster in the regions around 1 and 2 degrees. The Devils Hole record has been chosen, since it was dated by absolute methods. Other climate records covering the same period also ha...
physics
9,734
Testing of the transionospheric radiochannel using data from the global GPS network
physics.geo-ph
Using the international ground-based network of two-frequency receivers of the GPS navigation system provides a means of carrying out a global, continuous and fully-computerized monitoring of phase fluctuations of signals from satellite-borne radio engineering systems caused by the Earth's inhomogeneous and nonstationa...
physics
9,735
Degradation of GPS performance in geomagnetically disturbed conditions
physics.geo-ph
The GPS performance is impaired in conditions of geomagnetic distrubances. The rms error of positioning accuracy increases in the case where two-frequency GPS receivers of three main types (ASHTECH, TRIMBLE, and AOA) are in operation. For ASHTECH receivers (unlike AOA and TRIMBLE) there is also a clear correlation betw...
physics
9,736
Traveling wave packets of total electron content disturbances as deduced from global GPS network data
physics.geo-ph
We identified a new class of mid-latitude medium-scale traveling ionospheric disturbances (MS TIDs), viz. traveling wave packets (TWPs) of total electron content (TEC) disturbances. For the first time, the morphology of TWPs is presented for 105 days. Using the technique of GPS interferometry of TIDs we carried out a d...
physics
9,737
An Fe-Si-Ni solidification model of the Earth's layering
physics.geo-ph
The physical process creating layered structure in planetary rocky bodies is considered here to be multicomponent solidification. This is a unified alternative approach to the present interpretations where each layer is reasoned and matched individually. The Earth's solidification is modelled using the ternary phase di...
physics
9,738
Isolated ionospheric disturbances as deduced from global GPS network
physics.geo-ph
We investigate an unusual class of medium-scale traveling ionospheric disturbances (MS TIDs) of the nonwave type, isolated ionospheric disturbances (IIDs) that manifest themselves in total electron content (TEC) variations in the form of single aperiodic negative TEC disturbances of a duration of about 10 min (the tota...
physics
9,739
Degradation of signals and operation failures of radio engineering satellite systems during geospace disturbances accompanied by abrupt changes in the geomagnetic field
physics.geo-ph
During strong magnetic storms, the errors of determination of the range, frequency Doppler shift and angles of arrival of transionospheric radio signals exceeds the one for magnetically quiet days by one order of magnitude as a minimum. This can be the cause of performance degradation of current satellite radio enginee...
physics
9,740
The electromagnetic fields under, on and over Earth surface as when, where and how earthquake precursor
physics.geo-ph
It is given an attempt for statistical estimation of when earthquake prediction for Balkan- Black Sea region using the geomagnetic field signal. The preliminary test of the approach for England (Hartland), Turkey (Kandilli) and India (Alibag) regions is presented. The research step by step program for creating when, wh...
physics
9,741
Importance of direct and indirect triggered seismicity
physics.geo-ph
Using the simple ETAS branching model of seismicity, which assumes that each earthquake can trigger other earthquakes, we quantify the role played by the cascade of triggered seismicity in controlling the rate of aftershock decay as well as the overall level of seismicity in the presence of a constant external seismici...
physics
9,742
Are Aftershocks of Large Californian Earthquakes Diffusing?
physics.geo-ph
We analyze 21 aftershock sequences of California to test for evidence of space-time diffusion. Aftershock diffusion may result from stress diffusion and is also predicted by any mechanism of stress weakening. Here, we test an alternative mechanism to explain aftershock diffusion, based on multiple cascades of triggerin...
physics
9,743
Absolute palaeointensity of Oligocene (28-30 Ma) lava flows from the Kerguelen Archipelago (southern Indian Ocean)
physics.geo-ph
We report palaeointensity estimates obtained from three Oligocene volcanic sections from the Kerguelen Archipelago (Mont des Ruches, Mont des Tempetes, and Mont Rabouillere). Of 402 available samples, 102 were suitable for a palaeofield strength determination after a preliminary selection, among which 49 provide a reli...
physics
9,744
Mono Lake or Laschamp geomagnetic event recorded from lava flows in Amsterdam Island (southeastern Indian Ocean)
physics.geo-ph
We report a survey carried out on basalt flows from Amsterdam Island in order to check the presence of intermediate directions interpreted to belong to a geomagnetic field excursion within the Brunhes epoch, completing this paleomagnetic record with paleointensity determinations and radiometric dating. The directional ...
physics
9,745
Neutron-gravity interferometry experiment: testing Earth's rotating frequency fluctuations via neutron Berry's phases due to spin-rotation couplings
physics.geo-ph
Neutron spin can be coupled to the Earth's rotating frequency. Once if the Earth's rotating frequency is time-dependent, then the neutron will acquire a Berry's topological phase (cyclic adiabatic geometric phase). So, a potential method to investigate the Earth's time-varying rotating frequency by measuring the phase ...
physics
9,746
Revisiting the Jurassic Geomagnetic Reversal recorded in the Lesotho Basalt (Southern Africa)
physics.geo-ph
We carried out a detailed and continuous paleomagnetic sampling of the reversed to normal geomagnetic transition recorded by some 60 consecutive flow units near the base of the Lesotho Basalt (183  1 Ma). After alternating field or thermal cleaning the directions of remanence are generally well clustered within...
physics
9,747
Bath's law Derived from the Gutenberg-Richter law and from Aftershock Properties
physics.geo-ph
The empirical Bath's law states that the average difference in magnitude between a mainshock and its largest aftershock is 1.2, regardless of the mainshock magnitude. Following Vere-Jones [1969] and Console et al. [2003], we show that the origin of Bath's law is to be found in the selection procedure used to define mai...
physics
9,748
Melting of San Carlos olivine in the presence of carbon at 6-12 GPa
physics.geo-ph
Experiments at 6-12 GPa showed that San Carlos olivine surrounded by carbon melts incongruently at 1400 C and higher temperatures, producing olivine with lower Fe contents, pyroxene, carbide, and carbonate melt. The relatively low melting temperature of 1400 C, independent of pressure, is consistent with carbonate melt...
physics
9,749
Intercluster Correlation in Seismicity
physics.geo-ph
Mega et al.(cond-mat/0212529) proposed to use the ``diffusion entropy'' (DE) method to demonstrate that the distribution of time intervals between a large earthquake (the mainshock of a given seismic sequence) and the next one does not obey Poisson statistics. We have performed synthetic tests which show that the DE is...
physics
9,750
Post glacial rebounds measure the viscosity of the lithosphere
physics.geo-ph
The observed higher uplift rates before the end of deglaciation requires the existence of a low viscosity channel or layer. The uplifts observed after the end of deglaciation does not show any contribution from this low viscosity channel and a homogeneous viscosity model fits very well to the observed uplift. Most of t...
physics
9,751
Spectral element modeling of three dimensional wave propagation in a self-gravitating Earth with an arbitrarily stratified outer core
physics.geo-ph
This paper deals with the spectral element modeling of seismic wave propagation at the global scale. Two aspects relevant to low-frequency studies are particularly emphasized. First, the method is generalized beyond the Cowling approximation in order to fully account for the effects of self-gravitation. In particular, ...
physics
9,752
Dynamics of Crystal Formation in the Greenland NorthGRIP Ice Core
physics.geo-ph
The North Greenland Ice Core Project (NorthGRIP) provides paleoclimatic information back to at about 120 kyr before present (Dahl-Jensen and others, 2002). Each year, precipitation on the ice sheet covers it with a new layer of snow, which gradually transforms into ice crystals as the layer sinks into the ice sheet. Th...
physics
9,753
Study of the atmospheric pressure loading signal in VLBI observations
physics.geo-ph
Redistribution of air masses due to atmospheric circulation causes loading deformation of the Earth's crust which can be as large as 20 mm for the vertical component and 3 mm for horizontal components. Rigorous computation of site displacements caused by pressure loading requires knowledge of the surface pressure field...
physics
9,754
Raining lead around 250mya : a smoking gun for an Australian impact origin of the Permian Extinction
physics.geo-ph
Recent documentation of extreme atmospheric sulfur and methane contents at the time of the vast Permo-Triassic (P-T) extinction makes it possible to interpret an observation that has lain unnoticed in the geological literature for 40 years. This is the finding of microscopic metallic lead tear drops in the fluvial stra...
physics
9,755
Influence of squirt flow on fundamental guided waves propagation in borehole embedded in saturated porous media
physics.geo-ph
In this paper, the reservoir is modeled by homogeneous two-phase media based on BISQ model. We focus on the effects of the squirt flow on the fundamental guided waves propagation in borehole embedded in saturated porous media excited by monopole, dipole and quadrupole point sources. The full waveforms acoustic logging ...
physics
9,756
Reverse Detection of Short-Term Earthquake Precursors
physics.geo-ph
We introduce a new approach to short-term earthquake prediction based on the concept of selforganization of seismically active fault networks. That approach is named "Reverse Detection of Precursors" (RDP), since it considers precursors in reverse order of their appearance. This makes it possible to detect precursors u...
physics
9,757
2D ground motion at a soft viscoelastic layer/hard substratum site in response to SH cylindrical seismic waves radiated by deep and shallow line sources
physics.geo-ph
We show, essentially by theoretical means, that for a site with the chosen simple geometry and mechanical properties (horizontal, homogeneous, soft viscoelastic layer of infinite lateral extent overlying, and in welded contact with, a homogeneous, hard elastic substratum of half-infinite radial extent, shear-horizontal...
physics
9,758
Atmospheric pressure loading for routine data analysis
physics.geo-ph
We have computed 3-D displacements induced by atmospheric pressure loading from 6-hourly surface pressure field from NCEP (National Center for Environmental Predictions) Reanalysis data for all Very Long Baseline Interferometry) and SLR (Satellite Laser Ranging) stations. We have quantitatively estimated the error budg...
physics
9,759
Using a Numerical Weather Model to Improve Geodesy
physics.geo-ph
The use of a Numerical Weather Model (NWM) to provide in situ atmosphere information for mapping functions of atmosphere delay has been evaluated using Very Long Baseline Interferometry (VLBI) data spanning eleven years. Parameters required by the IMF mapping functions (Niell 2000, 2001) have been calculated from the N...
physics
9,760
Bernoulli process with 282 ky periodicity is detected in the R-N reversals of the earth's magnetic field
physics.geo-ph
Investigating the polarity time scales for the last 118 My a Bernoulli process with p=0.5 overriding with a Gaussian noise have been detected for the R-N magnetic reversals. The Bernoulli trials are separated by 282 ky. The frequency of the Bernoulli process correlates to planetary cycles and consistent with an impact ...
physics
9,761
Strain-induced kinetics of intergrain defects as the mechanism of slow dynamics in the nonlinear resonant response of humid sandstone bars
physics.geo-ph
A closed-form description is proposed to explain nonlinear and slow dynamics effects exhibited by sandstone bars in longitudinal resonance experiments. Along with the fast subsystem of longitudinal nonlinear displacements we examine the strain-dependent slow subsystem of broken intergrain and interlamina cohesive bonds...
physics
9,762
Quest for the Nuclear Georeactor
physics.geo-ph
The paper focuses on a proposal for an underground antineutrino antenna to further develop the dectection of these particles as a tool to map the distribution of radiogenic heat sources, such as the natural radionuclides and a hypothetical nuclear georeactor.
physics
9,763
Earthquakes temporal occurrence: a statistical study
physics.geo-ph
The distribution of inter-occurrence time between seismic events is a quantity of great interest in seismic risk assessment. We evaluate this distribution for different models of earthquakes occurrence and follow two distinct approaches: The non homogeneous Poissonian and the non Poissonian one. In all cases we obtain ...
physics
9,764
Seismic Activity in Tucunduba Reservoir, Senador Sa-CE, Brazil, 1997-1998
physics.geo-ph
The Tucunduba Dam is about 290 km West of Fortaleza, Cear\'a state. The seismic monitoring of the area, with a local network, has began on June 11, 1997, soon after the occurrence of the event with magnitude 3.2 $m_b$ on June 09, 1997. The monitoring was done with one the analogical station (used for magnitude duration...
physics
9,765
Importance of small earthquakes for stress transfers and earthquake triggering
physics.geo-ph
We estimate the relative importance of small and large earthquakes for static stress changes and for earthquake triggering, assuming that earthquakes are triggered by static stress changes and that earthquakes are located on a fractal network of dimension D. This model predicts that both the number of events triggered ...
physics
9,766
Multifractal Scaling of Thermally-Activated Rupture Processes
physics.geo-ph
We propose a ``multifractal stress activation'' model combining thermally activated rupture and long memory stress relaxation, which predicts that seismic decay rates after mainshocks follow the Omori law $\sim 1/t^p$ with exponents $p$ linearly increasing with the magnitude $M_L$ of the mainshock and the inverse tempe...
physics
9,767
Altitude dependence of atmospheric temperature trends: Climate models versus observation
physics.geo-ph
As a consequence of greenhouse forcing, all state of the art general circulation models predict a positive temperature trend that is greater for the troposphere than the surface. This predicted positive trend increases in value with altitude until it reaches a maximum ratio with respect to the surface of as much as 1.5...
physics
9,768
Disparity of tropospheric and surface temperature trends: New evidence
physics.geo-ph
Observations suggest that the earth's surface has been warming relative to the troposphere for the last 25 years; this is not only difficult to explain but also contrary to the results of climate models. We provide new evidence that the disparity is real. Introducing an additional data set, R2 2 meter temperatures, a d...
physics
9,769
Computation of a homogeneous coordinate time series for European GPS stations by reprocessing of the weekly EPN solutions
physics.geo-ph
Weekly coordinate time series for the all EPN (European Permanent GPS Network) stations for the period of observations beginning from GPS week 834 was obtained by a reprocessing of the official EPN solutions. Comparison of this series with EPN Central Bureau (EPN CB) and the previous IAA two-year solution for selected ...
physics
9,770
A New Free Core Nutation Model with Variable Amplitude and Period
physics.geo-ph
Three most long and dense VLBI nutation series obtained at the Goddard Space Flight Center, Institute of Applied Astronomy, and U.S. Naval Observatory were used for investigation of the Free Core Nutation (FCN) contribution to the celestial pole offset. Some recent studies have showed that the FCN period or/and phase d...
physics
9,771
Detection of Phase Jumps of Free Core Nutation of the Earth and their Concurrence with Geomagnetic Jerks
physics.geo-ph
We detected phase jumps of the Free Core Nutation (FCN) of the Earth directly from the analysis of the Very Long Baseline Interferometer (VLBI) observation of the Earth rotation for the period 1984-2003 by applying the Weighted Wavelet Z-Transform (WWZ) method and the Short-time Periodogram with the Gabor function (SPG...
physics
9,772
A Note on the Dipole Coordinates
physics.geo-ph
A couple of orthogonal coordinates for dipole geometry are proposed for numerical simulations of plasma geophysics in the Earth's dipole magnetic field. These coordinates have proper metric profiles along field lines in contrast to the standard dipole coordinate system that is commonly used in analytical studies for di...
physics
9,773
GPS radio occultation with GRACE: Atmospheric profiling utilizing the zero difference technique
physics.geo-ph
Radio occultation events recorded on 28-29 July 2004 by a GPS receiver aboard the GRACE-B satellite are analyzed. The stability of the receiver clock allows for the derivation of excess phase profiles using a zero difference technique, rendering the calibration procedure with concurrent observations of a reference GPS ...
physics
9,774
The axial ratio of hcp iron at the conditions of the Earth's inner core
physics.geo-ph
We present ab initio calculations of the high-temperature axial c/a ratio of hexagonal-close-packed (hcp) iron at Earth's core pressures, in order to help interpret the observed seismic anisotropy of the inner core. The calculations are based on density functional theory, which is known to predict the properties of hig...
physics
9,775
On the Frequency-magnitude Law for Fractal Seismicity
physics.geo-ph
Scaling analysis of seismicity in the space-time-magnitude domain very often starts from the relation N(m,L)=a(L)*10**(-bm)*L**c for the rate of seismic events of magnitude M>m in an area of size L. There are some evidences in favor of multifractal property of seismic process. In this case the choice of the scale expon...
physics
9,776
Investigation of initiation of gigantic jets connecting thunderclouds to the ionosphere
physics.geo-ph
The initiation of giant electrical discharges called as "gigantic jets" connecting thunderclouds to the ionosphere is investigated by numerical simulation method in this paper. Using similarity relations, the triggering conditions of streamer formation in laboratory situations are extended to form a criterion of initia...
physics
9,777
Multigrid iterative algorithm using pseudo-compressibility for three-dimensional mantle convection with strongly variable viscosity
physics.geo-ph
A numerical algorithm for solving mantle convection problems with strongly variable viscosity is presented. Equations for conservation of mass and momentum for highly viscous and incompressible fluids are solved iteratively by a multigrid method in combination with pseudo-compressibility and local time stepping techniq...
physics
9,778
Climate sensitivity of Earth to solar irradiance: update
physics.geo-ph
This paper is a continuation of a study by Douglass and Clader. We extend the analysis through December 2003 using the latest updates of the observational temperature and solar irradiance data sets in addition to a new volcano proxy data set. We have re-determined the solar effect on the temperature from satellite meas...
physics
9,779
Constraints on the Size of the Smallest Triggering Earthquake from the ETAS Model, Baath's Law, and Observed Aftershock Sequences
physics.geo-ph
The physics of earthquake triggering together with simple assumptions of self-similarity impose the existence of a minimum magnitude m0 below which earthquakes do not trigger other earthquakes. Noting that the magnitude md of completeness of seismic catalogs has no reason to be the same as the magnitude m0 of the small...
physics
9,780
Apparent Clustering and Apparent Background Earthquakes Biased by Undetected Seismicity
physics.geo-ph
In models of triggered seismicity and in their inversion with empirical data, the detection threshold m_d is commonly equated to the magnitude m_0 of the smallest triggering earthquake. This unjustified assumption neglects the possibility of shocks below the detection threshold triggering observable events. We introduc...
physics
9,781
Theory of tectonics in the sphere
physics.geo-ph
Soft or Deformable Plate Tectonics in the sphere must follow geometric rules inferred from the orthographic projection. An analytic equivalent of this geometry can be derived by the application of Potential Field Methods in the case of Atlantic type oceans. Laplace equation must be obeyed by the velocity field between ...
physics
9,782
Deghosting of Ocean Bottom Cable Data:Two approaches
physics.geo-ph
Two filter based approaches for deghosting of Ocean Bottom Cable data are presented. One of them is phase shifting of geophone followed by least square matching of cross ghosted geophone and hydrophone data.In the second approach,phase shifting of geophone is followed by direct matching of geophone's amplitude spectrum...
physics
9,783
A New Global Theory of the Earth's Dynamics : a Single Cause Can Explain All the Geophysical and Geological Phenomena
physics.geo-ph
After describing all the contradictions associated with the current Plate Tectonics theory, this paper proposes a model where a single cause can explain all geophysical and geological phenomena. The source of the Earth's activity lies in the difference of the angular velocities of the mantle and of the solid inner core...
physics
9,784
Visco-magnetic torque at the core mantle boundary
physics.geo-ph
A magneto-hydrodynamic model of boundary layers at the Core-Mantle Boundary (CMB) is derived and used to compute the viscous and electromagnetic torques generated by the Earth's nutation forcing. The predicted electromagnetic torque alone cannot account for the dissipation estimated from the observations of the free co...
physics
9,785
Relationship between acoustic body waves and in situ stresses around a borehole
physics.geo-ph
This paper shows that there are three types of shape of acoustic body waves propagating inside competent and homogeneous formations penetrated by a borehole : simple, double, and resonant. This fact is connected to the modifications undergone by the area located around a well after drilling in relation to in situ state...
physics
9,786
Is the San Andreas Fracture a bayonet-shaped fracture as inferred from the acoustic body waves in the SAFOD Pilot hole ?
physics.geo-ph
The method using the propagation of acoustic body waves within the stress modified areas around a vertical borehole has been applied to the granitic formation penetrated by the SAFOD Pilot hole near the San Andreas Fault trace. This method allows us investigating the horizontal in situ stresses. Only P waves supplied u...
physics
9,787
Numerical simulation of lava flows based on depth-averaged equations
physics.geo-ph
Risks and damages associated with lava flows propagation (for instance the most recent Etna eruptions) require a quantitative description of this phenomenon and a reliable forecasting of lava flow paths. Due to the high complexity of these processes, numerical solution of the complete conservation equations for real la...
physics
9,788
Gravity is indeed the driving force for fault pattern formation and westward displacement of the lithosphere
physics.geo-ph
Gravity influence of the Sun and the Moon on the Earth is the cause of the fault pattern on Earth's surface we observe nowadays and also of the westward displacement of the lithosphere. A somewhat related hypotheses advanced in the past have been that tidal torque of the Moon may be significant. However, it has been ar...
physics
9,789
A physical model for aftershocks triggered by dislocation on a rectangular fault
physics.geo-ph
We find the static displacement, stress, strain and the modified Columb failure stress produced in an elastic medium by a finite size rectangular fault after its dislocation with uniform stress drop but a non uniform dislocation on the source. The time-dependent rate of triggered earthquakes is estimated by a rate-stat...
physics
9,790
Evidences of a threshold system as the source for magnetic storms detected on Earth s surface
physics.geo-ph
Threshold systems appear to underlie the global behaviour of physical phenomena very unlike at a first look. The usual experimental fingerprint of threshold system grounded phenomena is the presence of power laws. Experimental evidence has been found, for example, in superconductor vortex avalanches, sand piles, the br...
physics
9,791
First principles study of density, viscosity, and diffusion coefficients of liquid MgSiO3 at conditions of the Earth's deep mantle
physics.geo-ph
Constant-pressure constant-temperature {\it ab initio} molecular dynamics simulations at high temperatures have been used to study MgSiO$_3$ liquid, the major constituent of the Earth's lower mantle to conditions of the Earth's core-mantle boundary (CMB). We have performed variable-cell {\it ab initio} molecular dynami...
physics
9,792
Global permanent deformations triggered by the Sumatra earthquake
physics.geo-ph
The giant Sumatra-Andaman earthquake of December 26 2004 caused permanent deformations effects in a region of previously never observed extension. The GPS data from the world wide network of permanent IGS sites show significant coseismic displacements in an area exceeding 107 km^2. The effects of the permanent residual...
physics
9,793
Transient deformations in the Suez-Sinai area from GPS observations
physics.geo-ph
We analyze data from four GPS campaigns carried out between 1997 and 2002 on a network of 11 sites in the Suez-Sinai, the area of collision between the African and the Arabian plates. This is the key area to understand how and in which way Sinai behaves like a sub-plate of the African plate and the role played between ...
physics
9,794
Geodynamo and mantle convection simulations on the Earth Simulator using the Yin-Yang grid
physics.geo-ph
We have developed finite difference codes based on the Yin-Yang grid for the geodynamo simulation and the mantle convection simulation. The Yin-Yang grid is a kind of spherical overset grid that is composed of two identical component grids. The intrinsic simplicity of the mesh configuration of the Yin-Yang grid enables...
physics
9,795
Comparative study of P and S wave amplitudes of acoustic logging through solid formations : contribution to the knowledge of in situ stresses and fractures
physics.geo-ph
In order to compare the ratios between the amplitudes of P and S acoustic waves drawn from various boreholes, we have defined a specific wave parameter called magnitude : for each shot, we have added the maximum positive amplitude values and the absolute values of the minimum negative amplitudes of a given wave recorde...
physics
9,796
Magnitude clustering and dynamical scaling in trigger models for earthquake forecasting
physics.geo-ph
One of the main interests in seismology is the formulation of models able to describe the clustering in time occurrence of earthquakes. Analysis of the Southern California Catalog shows magnitude clustering in correspondence to temporal clustering. Here we propose a dynamical scaling hypothesis in which time is rescale...
physics
9,797
Modification of the pattern informatics method for forecasting large earthquake events using complex eigenvectors
physics.geo-ph
Recent studies have shown that real-valued principal component analysis can be applied to earthquake fault systems for forecasting and prediction. In addition, theoretical analysis indicates that earthquake stresses may obey a wave-like equation, having solutions with inverse frequencies for a given fault similar to th...
physics
9,798
Eulerian Derivation of the Coriolis Force
physics.geo-ph
In textbooks of geophysical fluid dynamics, the Coriolis force and the centrifugal force in a rotating fluid system are derived by making use of the fluid parcel concept. In contrast to this intuitive derivation to the apparent forces, more rigorous derivation would be useful not only for the pedagogical purpose, but a...
physics
9,799
Correlation between the parameters of the rate equation for simple aftershock sequences: implications for the forecasting of rates and probabilities
physics.geo-ph
We analyzed the correlations among the parameters of the Reasenberg and Jones (1989) formula describing the aftershock rate after a mainshock as a function of time and magnitude, on the basis of parameter estimates made in previous works for New Zealand, Italy and California. For all of three datasets we found that the...
physics