Lithosphere-Atmosphere-Ionosphere Coupling Processes for Pre-, Co-, and Post Earthquakes: A case study of Northern Mariana, U.S.A. Earthquake of 31st October, 2007

Using the Plasma analyzer (IAP)and Langmuir Probe (ISL) experiments of the (Detection of Electromagnetic Emissions Transmitted from Earthquake Regions (DEMETER) and Total Electron Content (TEC) from GPS data, lithospheric-atmospheric - ionospheric coupling has been observed before, during and after the magnitude 7.2 Northern Mariana, U.S.A. Earthquake of 31st October, 2007. Both sets of data recorded perturbations within the investigative period. The study revealed pre – ionospheric variations on -17 day in the TEC with a value of 3.57 Total electron content unit (TECU) at 8:00 UTC while the IAP and ISL (Electron density) sensors of the DEMETER had 2.83 cm3 and 3.95 cm3 respectively on - 4 days. All pre -ionospheric perturbations were recorded in the morning. A co - ionospheric perturbation was revealed by the Electron Density with a value of -2.04 cm3 during the night time reading on the earthquake day (day 0). Four post - seismic day perturbations were recorded on day 2 (2.35 K and day 3 (2.15 K) from Electron temperature of the ISL experiment and 2.18 cm3 and 3.98 cm3 on days 5 and 7 respectively from the IAP sensor. The observed anomalies were screened for false alarm using the geomagnetic indices of Kernnifzer digit (Kp) and disturbance storm time (Dst.) It was however realized that the state of the ionosphere was geomagnetically quiet on these days; hence the observed variations were seismogenic.