Geomagnetic anomaly associated with Fukushima earthquake on February 13th, 2021

Cipta Ramadhani,Rosmaliati Rosmaliati,Teti Zubaidah,Bulkis Kanata,Abdullah Zainuddin

doi:10.1051/e3sconf/202133107012

Abstract

In this study, we performed research on electromagnetic anomalies related to earthquakes as early signs (precursors) that occurred in Fukushima, Japan on February 13th, 2021. The research focused on the utilization of geomagnetic field data which was derived from the Kakioka (KAK), Kanoya (KNY), and Memambetsu (MMB) observatories, particularly in the ultra-low frequency (ULF) to detect earthquake precursors. The method of electromagnetic data processing was conducted by applying a polarization ratio. In addition, we improved the methodology by splitting the ULF data (which ranged from 0.01-0.1 Hz) into 9 central frequencies and picking up the highest value from each central frequency to get the polarization ratio. The anomaly of magnetic polarization was identified 2-3 weeks before the mainshock in a narrowband frequency in the range of 0.04-0.05 Hz.

Highlights

Earthquakes are one of the deadliest natural disasters that occur suddenly and locally
The Fukushima earthquake with a magnitude of M7.1 occurred on Saturday, February 13th, 2021 at 14:07:49 (UTC) and has been reviewed by seismologists
We present the results of the polarization ratio analysis for the earthquake that occurred in Fukushima on February 13th, 2021

Summary

Introduction

Earthquakes are one of the deadliest natural disasters that occur suddenly and locally. Signs (precursors) to detect the occurrence of an earthquake need to be conducted to reduce the hazard. Short-term earthquake forecasting gives promising results which have a time scale of about a week to a month before the event. Shortterm earthquake forecasting can be potentially feasible by using geomagnetic disturbance observation instead of solely using seismometers. The weakness of using a seismometer is due to its limited sensitivity in detecting the generation of micro-fractures before an earthquake [1]. Research on electromagnetic anomalies related to earthquakes as precursors has attracted the attention of many researchers

Methods

Discussion

Conclusion