Oceans cover about seventy percent of the Earth and yet the overwhelming majority of seismological or electromagnetic (EM) observatories are found on continents. This provides a challenge for understanding composition, structure, and dynamics of Earth’s lithosphere and upper mantle in oceanic regions. The recent expansion in magnetic data from low-Earth orbiting satellite missions (Ørsted, CHAMP, SAC-C, and Swarm) has led to a rising interest in probing Earth from space. The largest benefit of using satellite data is much improved spatial coverage. Additionally, and in contrast to ground-based data, satellite data are overall uniform and very high quality. Probing the conductivity of the lithosphere and upper mantle requires EM variations with periods of a few hours. Electric currents generated by oceanic tides are a well-suited source within this period range. Ocean tides interact galvanically with Earth’s lithosphere (i.e. by direct coupling of the source currents in the ocean with the underlying substrate), enabling conductivity estimations at shallower depths. Here we present the results of determining a 1-D conductivity-depth profile of oceanic lithosphere and upper mantle using satellite and seafloor magnetic signals from the M2 ocean tide. With these data we also make an attempt to detect lateral variability of the Earth’s conductivity.
|Number of pages||1|
|Publication status||Published - 2016|
|Event||ESA Living Planet Symposium 2016 - Prague, Czech Republic|
Duration: 9 May 2016 → 13 May 2016
|Conference||ESA Living Planet Symposium 2016|
|Period||09/05/2016 → 13/05/2016|