Improving data, metadata and service quality within Résif-SI

2021 ◽  
Author(s):  
Jonathan Schaeffer ◽  
Fabien Engels ◽  
Marc Grunberg ◽  
Christophe Maron ◽  
Constanza Pardo ◽  
...  
Keyword(s):  
Seismic Data ◽  
Geodetic Network ◽  
Service Availability ◽  
End User ◽  
The Core ◽  
Data Centre ◽  
The Earth ◽  
Seismological Data ◽  
Data Portal ◽  
Geophysical Observation

<p>Résif, the French seismological and geodetic network, was launched in 2009 in an effort to develop, modernize, and centralize geophysical observation of the Earth’s interior. This French research infrastructure uses both permanent and mobile instrument networks for continuous seismological, geodetic and gravimetric measurements.</p><p>Résif-SI is the Information System that manages, validates and distributes seismological data from Résif.</p><p>The construction of Résif-SI has lead to a federated organisation gathering several data and metadata producers (Nodes) and a national Seismological Data Centre.</p><p>The Résif Seismological Data Centre is one of 19 global centres distributing data and metadata in formats and using protocols which comply with International Federation of Digital Seismograph Networks (FDSN) standards. It is also one of the eleven nodes in EIDA, the European virtual data centre and seismic data portal in the European Plate Observing System (EPOS) framework.</p><p>Inside Résif-SI, each Node has it's specificities and dedicated procedures in order to manage and validate the data and metadata workflow from the station instruments to the Résif Seismological Data Centre.</p><p>To meet the expectations and needs of the end user in terms of data quality, metadata consistency and service availability, Résif-SI operates a complex set of quality enhancement operations.</p><p>This contribution will present the quality expectations that are in the core of Résif-SI, and show the methods and tools that help us meeting the expectations, and that could be of interest for the rest of the community.</p><p>We will then list some of our quality improvement projets and the expected results.</p>

Introductory remarks

1982 ◽  
Vol 306 (1492) ◽  
pp. 9-10 ◽  
Keyword(s):  
Seismic Data ◽  
Geomagnetic Field ◽  
Early History ◽  
The Moon ◽  
The Core ◽  
The Past ◽  
The Earth ◽  
History Of ◽  
The Subject ◽  
Additional Constraints

The suggestion for this Discussion Meeting was put forward more than three years ago. The format of the programme has changed many times since the original version, reflecting in part changing interests in different aspects of the subject. Of the 25 papers to be presented, only 5 discuss the constitution of the core, 13 deal with the geomagnetic field (including the secular variation and reversals) and all but 1 of the remaining 7 on geophysical interpretations are also concerned with the geomagnetic field. This emphasis on geomagnetism reflects the additional constraints that the absence or presence of a magnetic field may put on the constitution of all the planets and the Moon. In contrast to the Earth, the record of the first 10 9 years of planetary history is still at least partly preserved on the Moon, Mercury and Mars (and perhaps on Venus), and a study of this record on these other bodies may yield some information on the early history of the Earth. We have some seismic data for the Moon, but it is only for the Earth that we have a rich store of such data. In this connection, a word of caution is in order. It must not be forgotten that the structure of the Earth as revealed by seismic data is only a snapshot of what it is like today, and in many ways a very imperfect snapshot. There is no science of palaeoseismology, and seismic data tell us nothing about the structure of the Earth in the past nor of its evolution.

scholarly journals Understanding Micropolar Theory in the Earth Sciences I: The Eigenfrequency $$\omega _r$$

2021 ◽  
Author(s):  
Rafael Abreu ◽  
Stephanie Durand
Keyword(s):  
Seismic Data ◽  
Original Model ◽  
Micropolar Theory ◽  
Elastic Parameters ◽  
Material Parameters ◽  
The Earth ◽  
Seismic Experiment ◽  
Seismological Data ◽  
Micropolar Model ◽  
General Dynamic

AbstractEven though micropolar theories are widely applied for engineering applications such as the design of metamaterials, applications in the study of the Earth’s interior still remain limited and in particular in seismology. This is due to the lack of understanding of the required elastic material parameters present in the theory as well as the eigenfrequency $$\omega _r$$ ω r which is not observed in seismic data. By showing that the general dynamic equations of the Timoshenko’s beam is a particular case of the micropolar theory we are able to connect micropolar elastic parameters to physically measurable quantities. We then present an alternative micropolar model that, based on the same physical basis as the original model, circumvents the problem of the original eigenfrequency $$\omega _r$$ ω r laking in seismological data. We finally validate our model with a seismic experiment and show it is relevant to explain observed seismic dispersion curves.

EXTREME COMPRESSION BEHAVIOUR OF SOLIDS BASED ON THE ROY-ROY INVERTED EQUATION OF STATE

2008 ◽  
Vol 22 (07) ◽  
pp. 909-915
Author(s):  
R. S. CHAUHAN ◽  
K. LAL
Keyword(s):  
Equation Of State ◽  
Bulk Modulus ◽  
Organic Solids ◽  
Inorganic Solids ◽  
The Core ◽  
The Earth ◽  
Compression Behaviour ◽  
Seismological Data ◽  
Murnaghan Equation ◽  
Data Modifications

An analysis has been presented using the Roy-Roy equation of state (EOS), which represents an extended and modified version of the Murnaghan EOS. It is found that the value of [Formula: see text] for various types of solids remain between 5/3 and 2. The Roy-Roy EOS has been found to become applicable for the core of the Earth, predicting the values of the pressure and bulk modulus in the range of seismological data. Modifications suggested recently to remove the shortcomings of the Murnaghan equation have been discussed. The maximum values of [Formula: see text] obtained from the Roy-Roy EOS for different inorganic solids and organic solids are also discussed.

Ups and Downs

2018 ◽  
Author(s):  
Roy Livermore
Keyword(s):  
Mantle Convection ◽  
Laboratory Experiments ◽  
Inner Core ◽  
Computer Modelling ◽  
Great Depth ◽  
New Horizons ◽  
The Core ◽  
The Earth ◽  
The World ◽  
The 1960S

Despite the dumbing-down of education in recent years, it would be unusual to find a ten-year-old who could not name the major continents on a map of the world. Yet how many adults have the faintest idea of the structures that exist within the Earth? Understandably, knowledge is limited by the fact that the Earth’s interior is less accessible than the surface of Pluto, mapped in 2016 by the NASA New Horizons spacecraft. Indeed, Pluto, 7.5 billion kilometres from Earth, was discovered six years earlier than the similar-sized inner core of our planet. Fortunately, modern seismic techniques enable us to image the mantle right down to the core, while laboratory experiments simulating the pressures and temperatures at great depth, combined with computer modelling of mantle convection, help identify its mineral and chemical composition. The results are providing the most rapid advances in our understanding of how this planet works since the great revolution of the 1960s.

Effects of incomplete parameterization on full-wavefield viscoelastic seismic data for petrophysical reservoir properties

Geophysics ◽  
2007 ◽  
Vol 72 (3) ◽  
pp. O9-O17 ◽  
Author(s):  
Upendra K. Tiwari ◽  
George A. McMechan
Keyword(s):  
Seismic Data ◽  
Input Data ◽  
Elastic Model ◽  
Quality Factors ◽  
Noise Levels ◽  
Reservoir Properties ◽  
Estimated Parameters ◽  
Model Parameterization ◽  
The Earth ◽  
Incomplete Model

In inversion of viscoelastic full-wavefield seismic data, the choice of model parameterization influences the uncertainties and biases in estimating seismic and petrophysical parameters. Using an incomplete model parameterization results in solutions in which the effects of missing parameters are attributed erroneously to the parameters that are included. Incompleteness in this context means assuming the earth is elastic rather than viscoelastic. The inclusion of compressional and shear-wave quality factors [Formula: see text] and [Formula: see text] in inversion gives better estimates of reservoir properties than the less complete (elastic) model parameterization. [Formula: see text] and [Formula: see text] are sensitive primarily to fluid types and saturations. The parameter correlations are sensitive also to the model parameterization. As noise increases in the viscoelastic input data, the resolution of the estimated parameters decreases, but the parameter correlations are relatively unaffected by modest noise levels.

Dead-Ends and New Directions

2021 ◽  
Vol 15 (4) ◽  
pp. 327-347
Author(s):  
Jean Francesco A.L. Gomes
Keyword(s):  
Natural History ◽  
Scientific Theory ◽  
Good Science ◽  
Orthodox Christian ◽  
The Core ◽  
The Earth ◽  
New Directions ◽  
History Of ◽  
Evolutionary Science ◽  
Doctrine Of Creation

Abstract The aim of this article is to investigate how Abraham Kuyper and some late neo-Calvinists have addressed the doctrine of creation in light of the challenges posed by evolutionary scientific theory. I argue that most neo-Calvinists today, particularly scholars from the Vrije Universiteit Amsterdam (VU), continue Kuyper’s legacy by holding the core principles of a creationist worldview. Yet, they have taken a new direction by explaining the natural history of the earth in evolutionary terms. In my analysis, Kuyper’s heirs at the VU today offer judicious parameters to guide Christians in conversation with evolutionary science, precisely because of their high appreciation of good science and awareness of the nonnegotiable elements that make up the orthodox Christian narrative.

The density variation of the earth's central core*

1942 ◽  
Vol 32 (1) ◽  
pp. 19-29
Author(s):  
K. E. Bullen
Keyword(s):  
Pure Iron ◽  
Outer Boundary ◽  
Density Variation ◽  
Central Core ◽  
Good Precision ◽  
Wide Margin ◽  
The Core ◽  
The Earth ◽  
The Mean ◽  
Published Paper

ABSTRACT A detailed analysis of the problem of the earth's density variation has been extended to the earth's central core. It is shown that in the region between the outer boundary of the core and a distance of about 1400 km. from the earth's center the density ranges from 9.4 gm/cm.3 to 11.5 gm/cm.3 within an uncertainty which, if certain general assumptions are true, does not exceed 3 per cent. The density and pressure figures are, moreover, compatible with the existence of fairly pure iron in this part of the earth. The result for the earth's outer mantle as given in a previously published paper, together with those in the present paper, are found to give with good precision the density distribution in a region occupying 99 per cent of the earth's volume. Values of the density within 1400 km. of the earth's center are subject, however, to a wide margin of uncertainty, and there appears to be no means of resolving this uncertainty for the present. The most that can be said is that the mean density in the latter region is greater than 12.3 gm/cm.3 and may quite possibly be several gm/cm.3 in excess of this figure. In the present paper figures are also included for the variation of gravity and the distribution of pressure within the central core. The gravity results are shown to be subject to an appreciable uncertainty except within about 1000 km. of the outer boundary of the core, but the pressure results are expected to be closely accurate at all depths.

Free spheroidal vibrations of the earth at very long periods, Part I— Calculation of periods for several earth models

1963 ◽  
Vol 53 (3) ◽  
pp. 483-501 ◽  
Author(s):  
Leonard E. Alsop
Keyword(s):  
Inner Core ◽  
Computer Programs ◽  
Free Vibrations ◽  
Stoneley Waves ◽  
The Core ◽  
The Earth ◽  
Earth Models ◽  
Shear Modes ◽  
Phase And Group Velocities ◽  
Group Velocities

Abstract Periods of free vibrations of the spheroidal type have been calculated numerically on an IBM 7090 for the fundamental and first two shear modes for periods greater than about two hundred seconds. Calculations were made for four different earth models. Phase and group velocities were also computed and are tabulated herein for the first two shear modes. The behavior of particle motions for different modes is discussed. In particular, particle motions for the two shear modes indicate that they behave in some period ranges like Stoneley waves tied to the core-mantle interface. Calculations have been made also for a model which presumes a solid inner core and will be discussed in Part II. The two computer programs which were made for these calculations are described briefly.

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