Subglacial seismic reflection strategies when source amplitude and medium attenuation are poorly known

Seismic reflection techniques are a powerful way to probe physical properties of subglacial strata. Inversion of seismic data for physical properties may be hampered, however, by lack of knowledge of the source amplitude as well as lack of knowledge of the compressional and shear attenuation in the ice. New methods are described to measure the source signature that require no a priori knowledge of the ice attenuation profile. Another new method is described to obtain the angular dependence of the subglacial bed reflection coefficient that is relatively insensitive to knowledge of the ice attenuation. Finally, a correction is provided to a long-standing error in the literature regarding measurement of the bed normal incidence reflection coefficient.