Results 41 to 50 of about 57 (55)
Some of the next articles are maybe not open access.
Detection of tectonomagnetic events using multichannel predictive filtering
Journal of Geophysical Research: Solid Earth, 1981High‐precision geomagnetic measurement depends on eliminating variations of ionospheric and magnetospheric origin. The commonly used technique of simply taking differences between total field magnetometers is only partially successful. Our method involves finding the multichannel Wiener filters which predict the field variation at a given total field ...
P. M. Davis +3 more
openaire +1 more source
Investigations of tectonomagnetic phenomena in China
Physics of the Earth and Planetary Interiors, 1989Abstract The Tangshan earthquake ( M = 7.8, 28 July 1976) occurred in North China, where there is relatively dense network of geomagnetic observations. Before the earthquake there were anomalies of ∼ 8–10 nT in the total intensity of the geomagnetic field at Ninghe and Dongtietou sites, 50–90 km from the epicenter, and also in the Beijing survey ...
openaire +1 more source
Application of tectonomagnetism to earthquake phenomena
Tectonophysics, 1972Abstract The magnetization (J) of a rock compressed uniaxially by σ whose axis makes an angle θ with the direction of J is proved experimentally and theoretically to be presented by J(θ,σ) = Jo[1− (βσ 4) × (3 cos2θ + 1)] , where Jo denotes the magnetization of the uncompressed rock. Similarly, the magnetization of a rock under a uniaxial tension
openaire +1 more source
Reducing noise in tectonomagnetic experiments by linear regression
Journal of Geophysical Research: Solid Earth, 1979Noise in tectonomagnetic experiments caused by geomagnetic variations due to nonlocal sources can be reduced by applying multivariate linear regression to data from a network of magnetometer sites. Residuals obtained by subtracting from the observed values at a particular site the values calculated from a regression expression using the simultaneous ...
openaire +1 more source
A tectonomagnetic effect observed before a magnitude 5.2 earthquake near Hollister, California
Journal of Geophysical Research, 1976Simultaneous measurements of geomagnetic field with an array of seven proton precession magnetometers along the San Andreas fault show that the most significant local changes during 1974 were recorded at a site 11 km from a magnitude 5.2 earthquake that occurred on November 28, 1974.
B. E. Smith, M. J. S. Johnston
openaire +1 more source
Physics of the Earth and Planetary Interiors, 1979
Cancellation of extraterrestrial magnetic disturbances by taking simple differences between total field readings at spaced stations is imperfect. It is shown that improvement is possible when three component observatory data are available from a single station in the general, but not necessarily immediate, vicinity of an array of total field stations ...
Davis, P. M. +3 more
openaire +2 more sources
Cancellation of extraterrestrial magnetic disturbances by taking simple differences between total field readings at spaced stations is imperfect. It is shown that improvement is possible when three component observatory data are available from a single station in the general, but not necessarily immediate, vicinity of an array of total field stations ...
Davis, P. M. +3 more
openaire +2 more sources
Tectonophysics, 1974
Abstract Physical theory and laboratory experiments both indicate that tectonomagnetic effects in seismically active areas should be detected with highly sensitive drift-free differential magnetometers. By using a pair of synchronized 0.25 7 absolute magnetometers to measure precisely field differences between 70 adjacent sites with a 10–15 km ...
openaire +1 more source
Abstract Physical theory and laboratory experiments both indicate that tectonomagnetic effects in seismically active areas should be detected with highly sensitive drift-free differential magnetometers. By using a pair of synchronized 0.25 7 absolute magnetometers to measure precisely field differences between 70 adjacent sites with a 10–15 km ...
openaire +1 more source
Journal of Geophysical Research: Solid Earth, 1979
Previous geomagnetic field measurements in Colorado have been extended using three self‐calibrating rubidium magnetometers accurate to about 0.01 γ. The magnetometers were deployed either in an L‐shaped array or in a collinear array and provided simultaneous measurements of the scalar field at sites separated by 12–16 km.
openaire +1 more source
Previous geomagnetic field measurements in Colorado have been extended using three self‐calibrating rubidium magnetometers accurate to about 0.01 γ. The magnetometers were deployed either in an L‐shaped array or in a collinear array and provided simultaneous measurements of the scalar field at sites separated by 12–16 km.
openaire +1 more source
Tectonomagnetic Monitoring of the Wilhelm Archipelago in the Argentine Islands Area
International Conference of Young Professionals «GeoTerrace-2022», 2022V. Maksymchuk +4 more
openaire +1 more source