scholarly journals Ukrainian geomagnetic repeat station network and results of the field work reduced to the epoch 2005.5

2013 ◽  
Vol 55 (6) ◽  
Author(s):  
Valentyn Maksymchuk ◽  
Myxailo Orlyuk ◽  
Viktor Tregybenko ◽  
Yurij Horodyskyy ◽  
Dmytro Marchenko
Keyword(s):  
Geomagnetic Field ◽  
Field Work ◽  
Station Network ◽  
Repeat Station ◽  
Geodetic Measurements ◽  
Magnetic Declination

<p>The results of geomagnetic field components of the renewed Ukrainian repeat stations (RS) network are presented. The methods of absolute geomagnetic and astro-geodetic measurements are described. The reduction of geomagnetic field components is carried out to the 2005.5 epoch and a catalogue of RS is created. Maps of magnetic declination for the Ukraine are constructed and compared with results calculated by the IGRF-2005 model.</p><p> </p>

First Results of the 2019 Algerian Magnetic Repeat Station Network

2020 ◽  
Author(s):  
Abdenacuer Lemgharbi ◽  
Abdeslam Abtout ◽  
Mohamed Hamoudi ◽  
Abdelhamid Bendekken ◽  
Fatma Annad ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Secular Variation ◽  
Geomagnetic Field ◽  
Station Network ◽  
Repeat Station ◽  
First Results ◽  
Geomagnetic Field Models ◽  
Polynomial Modeling ◽  
History Of ◽  
Absolute Measurements

&lt;p&gt;&lt;strong&gt;Abstract:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;The second part of the history of the Algerian magnetic repeat station network goes back to 1989 when the new one was started with 37 stations. It was then followed by three other networks in 1993, 1997 and 2005. The first part of this history started at the beginning of the XX&lt;sup&gt;th&lt;/sup&gt; and ended ca 1956.&lt;/p&gt;&lt;p&gt;After a 14-year break, we launched a new repeat stations network in February 2019. The number of carried out stations was increased to 51 to try to cover all the territory.&lt;/p&gt;&lt;p&gt;Each repeat station network consists of stations of periodically, say &amp;#160;5-6 years, measured of three components of the Earth's magnetic field. to try to derive the spatial distribution of the geomagnetic field of Algeria and it's secular variation. This periodicity is also very important for the need to update local as well as global geomagnetic field models such as the International Geomagnetic Reference Field (IGRF).&lt;/p&gt;&lt;p&gt;In this work we describe the new 2019 Algerian repeat station network. Then we will discuss the steps of the absolute measurements using two methods. The first one is called the &amp;#8216;method of zero&amp;#8217; and the second one &amp;#8216;method of residuals&amp;#8217;. The accuracy and resolution of the instruments and data reduction used and their effect on the final results will as well be discussed. We derive the spatial distribution of the geomagnetic field, and its secular variation. Finally, we will show how local, for instance regional polynomial modeling, is the key issue.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Key words&lt;/strong&gt;: geomagnetic repeat network, absolute measurements, zero method, residual method, magnetic maps of Algeria, secular variation.&lt;/p&gt;

Analysis of Magnetic Anomaly Characteristics of Underground Non-Coplanar Cross-buried Iron Pipelines

2020 ◽  
Vol 25 (2) ◽  
pp. 223-233
Author(s):  
Pan Wu ◽  
Minghui Wei
Keyword(s):  
Magnetic Susceptibility ◽  
Magnetic Anomaly ◽  
Magnetic Dipole ◽  
Geomagnetic Field ◽  
Magnetic Anomalies ◽  
Buried Pipelines ◽  
Magnetic Declination ◽  
Magnetic Inclination ◽  
Basic Characteristics ◽  
Geomagnetic Intensity

The non-coplanar cross-buried pipelines are a common way of pipeline wiring. In order to investigate the magnetic anomaly characteristics of the non-coplanar cross-buried pipelines and guide the site operation, the influences of a series of factors on the magnetic anomaly of the non-coplanar cross-buried pipelines are analyzed. Based on the principle of magnetic dipole construction, a forward model is established for the magnetic anomaly characteristics of the subsurface non-coplanar cross-buried pipelines. The basic characteristics of magnetic anomaly for the non-coplanar cross-buried pipelines are defined. The influences of geomagnetic parameters (geomagnetic intensity, geomagnetic inclination, and geomagnetic declination), pipeline parameters (thickness, magnetic susceptibility), and cross angle of pipelines on the characteristics of magnetic anomalies are analyzed. The results show that the shape of the total magnetic anomaly is mainly affected by the magnetic inclination, and the curve of magnetic anomaly at ± I site shows some symmetry. The amplitude is approximately linearly affected by the total geomagnetic field, magnetic declination, pipeline thickness, material magnetic susceptibility, and pipeline cross angle. There is a periodic change of the amplitude with the increase of geomagnetic inclination (−90°–>90°). The crest-trough distance is mainly affected by geomagnetic inclination, magnetic declination, thickness, magnetic susceptibility, and pipeline cross angle. A more accurate measurement can be achieved if the direction of the pipelines is roughly measured and then the number of measurement points is augmented near the intersection of pipelines and the measurement lines. Present work obtains the equivalent magnetic dipole units by segmenting pipelines. The magnetic anomaly characteristics of non-coplanar crossed iron pipelines are successfully simulated. The numerical results are in accordance with the experimental analysis.

scholarly journals New Slovak geomagnetic repeat station network

2006 ◽  
Vol 58 (6) ◽  
pp. 751-755
Author(s):  
Fridrich Valach ◽  
Magdalena Vaczyova ◽  
Peter Dolinsky
Keyword(s):  
Station Network ◽  
Repeat Station

Reduction of a two‐gravimeter base network by linear regression

Geophysics ◽  
1985 ◽  
Vol 50 (5) ◽  
pp. 867-869
Author(s):  
C. Patrick Ervin
Keyword(s):  
Linear Regression ◽  
Regression Line ◽  
Field Work ◽  
Base Station ◽  
The Other ◽  
Base Stations ◽  
Simultaneous Operation ◽  
Station Network ◽  
Exploration Environment ◽  
Base Network

In the exploration environment, a primary application of gravity surveying is regional reconnaissance. The first step in such a survey is to establish a base‐station network. Since an error in the network will propagate to many stations in the subsequent survey, careful field work and accurate reduction of these data are particularly critical. Optimally, successive base stations are tied by minimum‐time loops using at least two meters read simultaneously. Using two meters has the obvious advantage of doubling the number of ties with minimal increase in time and cost. Erroneous readings are also much easier to detect and correct with two meters. Furthermore, the simultaneous operation of the meters allows calibrations of the two to be compared by computing a linear regression of the readings of one meter against the corresponding readings of the other. If the meter calibrations are identical, the regression line should have a slope of 1. A significant deviation from 1 indicates a systematic variation in calibration.

scholarly journals Improved observations at the southern African geomagnetic repeat station network

2007 ◽  
Vol 110 (2-3) ◽  
pp. 175-186 ◽  
Author(s):  
M. Korte ◽  
M. Mandea ◽  
P. Kotze ◽  
E. Nahayo ◽  
B. Pretorius
Keyword(s):  
Station Network ◽  
Repeat Station

scholarly journals Analysis of geomagnetic disturbances dynamics during increased solar activity and magnetic storms (according to the measurements of INTERMAGNET station network)

2019 ◽  
Vol 127 ◽  
pp. 02003
Author(s):  
Oksana Mandrikova ◽  
Anastasia Rodomanskay ◽  
Alexander Zaitsev
Keyword(s):  
Geomagnetic Activity ◽  
Geomagnetic Field ◽  
Auroral Zone ◽  
Magnetic Storms ◽  
Magnetic Data ◽  
Field Variation ◽  
Geomagnetic Disturbances ◽  
Station Network ◽  
Ground Station ◽  
Automated Method

We present and describe an automated method for analysis of magnetic data and for detection of geomagnetic disturbances based on wavelet transformation. The parameters of the computational algorithms allow us to estimate the characteristics of non-uniformly scaled peculiar properties in the variations of geomagnetic field that arise during increasing geomagnetic activity. The analysis of geomagnetic data before and during magnetic storms was carried out on the basis of the method according to ground station network. Periods of increasing geomagnetic activity, which precede and accompany magnetic storms, are highlighted. The dynamic of geomagnetic field variation in the auroral zone is considered in detail.

scholarly journals Repeat-station surveys: implications from chaos and ergodicity of the recent geomagnetic field

2013 ◽  
Vol 56 (1) ◽  
Author(s):  
Angelo De Santis ◽  
Enkelejda Qamili ◽  
Gianfranco Cianchini
Keyword(s):  
Time Series ◽  
Phase Space ◽  
Time Domain ◽  
Secular Variation ◽  
Geomagnetic Field ◽  
Repeat Station ◽  
Reconstructed Phase Space ◽  
Time Averages ◽  
The Time Domain ◽  
Strong Necessity

<p>The present geomagnetic field is chaotic and ergodic: chaotic because it can no longer be predicted beyond around 6 years; and ergodic in the sense that time averages correspond to phase-space averages. These properties have already been deduced from complex analyses of observatory time series in a reconstructed phase space and from global predicted and definitive models of differences in the time domain. These results imply that there is a strong necessity to make repeat-station magnetic surveys more frequently than every 5 years. This, in turn, will also improve the geomagnetic field secular variation models. This report provides practical examples and case studies.</p><p> </p>

scholarly journals Preliminary results of rock- and palaeomagnetic field work in Peary Land, North Greenland

1980 ◽  
Vol 99 ◽  
pp. 137-145
Author(s):  
N Abrahamsen ◽  
C Marcussen
Keyword(s):  
Geomagnetic Field ◽  
Field Work ◽  
Magnetic Data ◽  
Preliminary Results ◽  
Laboratory Investigations ◽  
North Greenland ◽  
Land Region

This paper reports on the palaeomagnetic field work carried out in the Peary Land region in 1979 (fig. 60) and presents some preliminary results of the laboratory investigations. Previous work relating to the geomagnetic field in North Greenland is very limited, and no palaeomagnetic and rock-magnetic data from Peary Land have hitherto been published.

How Accurate Geomagnetic Regional Modeling Using Ordinary Kriging For Clustered Distributed Data?: New Insight From Indonesian Archipelago

2021 ◽  
Author(s):  
Muhamad Syirojudin ◽  
Eko Haryono ◽  
Suaidi Ahadi
Keyword(s):  
Geomagnetic Field ◽  
Ordinary Kriging ◽  
Distributed Data ◽  
Geostatistical Modeling ◽  
Kriging Method ◽  
Spherical Cap ◽  
Repeat Station ◽  
Indonesian Archipelago ◽  
Typical Data ◽  
Spherical Cap Harmonic Analysis

Abstract Indonesia relies only on the limited number of repeat station networks due to the archipelago setting with the extensive sea with the clustery distributed pattern. This paper explored geostatistical modeling to overcome that typical data characteristic. The modeling used repeat station data from the 1985 to 2015 epoch. The research used ordinary kriging (OK) compared to the Spherical Cap Harmonic Analysis (SCHA) and Polynomial. The results show that the root means square error (RMSE) of each declination, inclination, and total intensity vary among epochs. OK method for declination component produces smaller average RMSE (7.67 minutes) than SCHA (9.26 minutes) and Polynomial (7.97minutes). For the inclination component, OK has an average RMSE of 9.55 minutes, smaller than SCHA (10.05) but slightly higher than Polynomial (9.36 minutes). For the total intensity component, OK produce an average RMSE of 63.58 nT, smaller than SCHA (82.24 nT) and Polynomial (68.97 nT). The finding shows that the kriging method can be a promising method to model the regional geomagnetic field, especially in the area of limited available data and clustered distributed data.

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