Science Alert October 10, 2022 Magnetic field changes as earthquake precursors have been the subject of numerous studies and some controversy. Infrequent large earthquakes and sparse magnetometer coverage along fault zones complicate statistical analysis. A team of researchers in the US (Google Research, industry) analyzed ground-based magnetic time-series measurements before 19 earthquakes in California drawing from over 330,000 site-days of measurement spanning a decade. They applied a pre-specified statistical analysis with two key ideas – combining signals from nearby sites via spectral cross-power, and then looking for large spikes in frequency domain 0.016–25 Hz. They used the machine learning concept […]
Tag Archives: Geophysics
The Mysterious Anomaly Weakening Earth’s Magnetic Field Seems to Be Splitting
Science Alert May 26, 2020 New satellite data from ESA reveal that the South Atlantic Anomaly is a vast expanse of reduced magnetic intensity in Earth’s magnetic field, extending all the way from South America to southwest Africa. Since our planet’s magnetic field acts as a kind of shield – protecting Earth from solar winds and cosmic radiation, in addition to determining the location of the magnetic poles – any reduction in its strength is an important event we need to monitor closely, as these changes could ultimately have significant implications for our planet. The ESA notes that the most […]