Advances in seismic data acqiuisition and interpretation for glaciological research on glaciers, ice sheets and shelves

Seismic data acquisition and interpretation belongs to the oldest geophysical methods used in glaciological research. Its has been in use since the beginning of the 20th century. However, since the advent of airborne radio-echo sounding (or radar), the amount of seismic work carried out on polar ice masses and glaciers has been decreasing. The reasons is that airborne radars can acquire much more data in a very short time, especially when it comes to sounding ice thicknesses, than ever possible with seismics. Seismic data can only be acquired with the seismic source and recorders, i.e. geophones, on the ground. Moreover, as the top tens of meters of polar ice masses consist of porous firn, the traditional application of explosive seismic sources require drilling of shot holes about 10 to 50 m deep into the firn to overcome strong wave attenuation. Such constraints make seismic works comparably slower than radar data acquisition. Despite such disadvantages, the mutual application of seismic and radar methods provide a strong synergy for enlighting the internal structure and property of ice masses, important for determining ice-dynamic flow parameters, as well as the properties of the sub-ice geology. A considerable improvement in seismic data acqiusition has been achieved over the last two years with the successful application of standard vibroseismic methods on cold firn, both, in the polar regions as well as on high-altitude Alpine glaciers. In this contribution we provide an overview over the achievments, both, technically and scientifically, obtained in the last two years