Magnetic "field free" spaces for paleomagnetism, rock magnetism, and other studies

1969 ◽  
Vol 6 (5) ◽  
pp. 1312-1316 ◽  
Author(s):  
J. L. Roy ◽  
W. A. Robertson ◽  
C. Keeping
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Rock Magnetism ◽  
Magnetic Storms ◽  
Earth’S Magnetic Field ◽  
Residual Field ◽  
Earth's Magnetic Field ◽  
Free Spaces

An array of five sets of 8-ft (244-cm) square coils for compensation of the earth's magnetic field at five locations is described. A fluxgate system is used to keep the residual field within 2 gammas during magnetic storms and 1 gamma in other instances. Constant fields (1 Oe down to a few gammas), for experiments in small magnetic fields, can be produced at four locations independently.

scholarly journals A magnetometer for the measurement of the Earth's vertical magnetic intensity in C. G. S. measure

1928 ◽  
Vol 117 (777) ◽  
pp. 434-458 ◽  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Vertical Component ◽  
Field Measurements ◽  
Horizontal Component ◽  
Magnetic Intensity ◽  
Earth’S Magnetic Field ◽  
Simple Operation ◽  
Horizontal Field ◽  
Earth's Magnetic Field

The measurement of the vertical component of the earth’s magnetic field is a less simple operation than that of the horizontal component. The horizontal field measurements are on a satisfactory basis, whether made by the swinging magnet method, or by the more recently developed electric magnetometers, in which known magnetic fields may be provided by means of known currents flowing through coils of known dimensions.

A Study of the Magnetic Field of the Moon

1962 ◽  
Vol 14 ◽  
pp. 45-52 ◽  
Author(s):  
S. S. Dolginov ◽  
E. G. Eroshenko ◽  
L. I. Zhuzgov ◽  
N. V. Pushkov
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
The Moon ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field ◽  
The Magnetic Field

The question as to whether the planets and their satellites possess magnetic fields unavoidably arose in connection with the question as to the origin of the Earth's mágnetic field and the nature of a number of geophysical effects.

Study of the Magnetic Fields of Residential Buildings and their Impact on Human Health

2021 ◽  
Vol 23 (4) ◽  
pp. 370-382
Author(s):  
Radka Kostadinova ◽  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Residential Buildings ◽  
Health Condition ◽  
Residential Areas ◽  
Earth’S Magnetic Field ◽  
The People ◽  
Specific Device ◽  
Earth's Magnetic Field ◽  
The Magnetic Field

With the prosperity of civilization people are more often put to the vibrations of the Earth’s magnetic field, which they are affecting by themselves in various ways. Settlements and residential areas, distant and electrical conductors, with its constantly changing electromagnetic field create strong deformations and weaken the Earth’s magnetic field. Is it possible that the reduction of the magnetic fields, in such buildings, to lead to illness and discomfort of the people living there. Is it possible that chronic discomfort and illness of the humans who inhabit those buildings don’t suffer from conditions, we usually connect with junk food, polluted air and the our stressful lifestyle, but are actually a result of the greatly reduced and changing magnetic field in the populated areas. With the research project developed by Tereza Stefanova with the help of students from the school, we tried to answer these questions. The purpose of our research is to: 1. Measure the magnetic field in buildings in our city, which differ by their construction and height and also to measure outside the city. 2. Determine if the change of the magnetic field and possible magnetic anomalies affect our health condition. The tasks we had to do to achieve our goal is to do take the measurements with a specific device.

scholarly journals Magnetosensitive neurons mediate geomagnetic orientation in Caenorhabditis elegans

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Andrés Vidal-Gadea ◽  
Kristi Ward ◽  
Celia Beron ◽  
Navid Ghorashian ◽  
Sertan Gokce ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Caenorhabditis Elegans ◽  
Magnetic Fields ◽  
Three Dimensions ◽  
Magnetic Orientation ◽  
Earth’S Magnetic Field ◽  
C Elegans ◽  
Central Neurons ◽  
Native Soil ◽  
Earth's Magnetic Field

Many organisms spanning from bacteria to mammals orient to the earth's magnetic field. For a few animals, central neurons responsive to earth-strength magnetic fields have been identified; however, magnetosensory neurons have yet to be identified in any animal. We show that the nematode Caenorhabditis elegans orients to the earth's magnetic field during vertical burrowing migrations. Well-fed worms migrated up, while starved worms migrated down. Populations isolated from around the world, migrated at angles to the magnetic vector that would optimize vertical translation in their native soil, with northern- and southern-hemisphere worms displaying opposite migratory preferences. Magnetic orientation and vertical migrations required the TAX-4 cyclic nucleotide-gated ion channel in the AFD sensory neuron pair. Calcium imaging showed that these neurons respond to magnetic fields even without synaptic input. C. elegans may have adapted magnetic orientation to simplify their vertical burrowing migration by reducing the orientation task from three dimensions to one.

scholarly journals The influence of the Earth’s magnetic field on strapdown inertial gravimetry using Q-Flex accelerometers: static and dynamic experiments

2021 ◽  
Vol 95 (9) ◽  
Author(s):  
Felix Johann ◽  
David Becker ◽  
Matthias Becker ◽  
Matthias Hoss ◽  
Alexander Löwer ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Measurement Errors ◽  
Calibration Function ◽  
Earth’S Magnetic Field ◽  
Dynamic Experiments ◽  
Dependent Measurement ◽  
Earth's Magnetic Field ◽  
First Time ◽  
Calibration Approach

AbstractIn recent strapdown airborne and shipborne gravimetry campaigns with servo accelerometers of the widely used Q-Flex type, results have been impaired by heading-dependent measurement errors. This paper shows that the effect is, in all likelihood, caused by the sensitivity of the Q-Flex type sensor to the Earth’s magnetic field. In order to assess the influence of magnetic fields on the utilised strapdown IMU of the type iMAR iNAV-RQH-1003, the IMU has been exposed to various magnetic fields of known directions and intensities in a 3-D Helmholtz coil. Based on the results, a calibration function for the vertical accelerometer is developed. At the example of five shipborne and airborne campaigns, it is outlined that under specific circumstances the precision of the gravimetry results can be strongly improved using the magnetic calibration approach: The non-adjusted RMSE at repeated lines decreased from 1.19 to 0.26 mGal at a shipborne campaign at Lake Müritz, Germany. To the knowledge of the authors, a significant influence of the Earth’s magnetic field on strapdown inertial gravimetry is demonstrated for the first time.

scholarly journals On certain average characteristics of world wide magnetic disturbance

1927 ◽  
Vol 115 (771) ◽  
pp. 242-267 ◽  
Keyword(s):  
Magnetic Field ◽  
Diurnal Variation ◽  
Local Time ◽  
World Wide ◽  
Magnetic Storms ◽  
The Other ◽  
Magnetic Disturbance ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field ◽  
Three Components

1. This paper forms a sequel to one entitled “An Outline of a Theory of Magnetic Storms,” published several years ago. In that paper I determined the average additional variations in the three components of the earth's magnetic field (for observatories in magnetic latitudes up to about 60°N.) which during times of considerable magnetic disturbance—commonly called magnetic storms —are superposed on the normal variations. The storms dealt with were such as had a commencement sufficiently definite for its epoch to be estimated to within an hour. The average additional variations of the field were shown to be separable into two parts, one depending on “storm-time” (that is, time reckoned from the commencement of the storm), and the other being a “diurnal” variation depending on local time. Besides these average variations there are, of course, less regular features peculiar to each individual storm.

scholarly journals RESPONSE OF BIOLOGICAL SYSTEMS TO GEOMAGNETIC STORMS

2018 ◽  
Vol 3 (5) ◽  
pp. 126-131
Author(s):  
A. A. Bazhenov ◽  
M. V. Prikop ◽  
A. S. Averina ◽  
V. V. Sukhovskaya ◽  
A. V. Ukhova
Keyword(s):  
Magnetic Field ◽  
Geomagnetic Activity ◽  
Geomagnetic Storms ◽  
Biological Systems ◽  
Magnetic Storms ◽  
Magnetic Observatory ◽  
Earth’S Magnetic Field ◽  
Motion Activity ◽  
Earth's Magnetic Field ◽  
The City

At present, influence of weak magnetic fields associated with solar and geomagnetic activity on biological systems is gaining more interest. Taking into account the accumulated data on the influence of geomagnetic storms on different biological levels, it is obvious that the mechanism of influence is universal. One of the approaches in this search may be the study of patterns and differences in the response to geomagnetic storms of various biological objects. As a research material served: data on the number of ambulance calls in the city of Irkutsk for acute myocardial infarction, cerebral infarction; results of retrospective analysis of the number of spontaneous parturition of the city of Irkutsk; data on the motion activity of fruit fly Drosophyla melanogaster, obtained by automated monitoring. The investigated indicators were compared with the parameters of geomagnetic activity at different time scales. As indicators of geomagnetic storms, three-hour (ap) and daily (Ap) equal to the average amplitude of variation of the geomagnetic field of the Earth. In the case of comparing the motion activity of fruit flies with magnetic storms, the local companions of the Earth’s magnetic field were additionally considered according to the data of the Irkutsk magnetic observatory. As a result of the conducted studies it was established that the detected response of biological systems depends on the characteristics of the state of the Earth’s magnetic field, which falls on the period of passage of magnetic storms. The obtained data also indicate possible gender differences in the response to the effects of the geomagnetic factor by organisms of different levels.

A COIL OF IMPROVED SENSITIVITY FOR ROCK MAGNETISM

Geophysics ◽  
1966 ◽  
Vol 31 (1) ◽  
pp. 149-152 ◽  
Author(s):  
G. Grenet
Keyword(s):  
Magnetic Field ◽  
Rock Magnetism ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Earth’S Magnetic Field ◽  
Cross Sectional ◽  
Earth's Magnetic Field ◽  
The Cross ◽  
Different Parts ◽  
Vibrational Noise

The sensitivity of a coil‐type magnetometer can be increased by varying the cross‐sectional area of the winding for different parts of the inner coil and by increasing the radius of the outer coil. The axis of the coil should be in the direction of the earth’s magnetic field in order to reduce vibrational noise.

Sign in / Sign up

Export Citation Format

Share Document