Determining fabric orientations from the dependence of reflected energy on polarisation azimuth for a continuous internal reflector in Antarctica

The reflected energy from a strong continuous radar reflector observed with airborne radio-echo sounding (RES) at the EPICA deep-drilling site in Dronning Maud Land, Antarctica, strongly depends on the direction of polarisation.The reflector's magnitude shows maximum values for polarisation par...

Full description

Bibliographic Details
Main Authors: Eisen, Olaf, Hamann, Ilka, Kipfstuhl, J., Steinhage, Daniel, Wilhelms, Frank
Format: Conference Object
Language:unknown
Published: 2008
Subjects:
Antarc*
Antarctica
Dronning Maud Land
EPICA
ice core
Online Access:https://epic.awi.de/id/eprint/18246/
https://hdl.handle.net/10013/epic.31354
Description
Summary:The reflected energy from a strong continuous radar reflector observed with airborne radio-echo sounding (RES) at the EPICA deep-drilling site in Dronning Maud Land, Antarctica, strongly depends on the direction of polarisation.The reflector's magnitude shows maximum values for polarisation parallel to the nearby ice divide and disappears for polarisation perpendicular to it. This indicates that the reflector originates from anisotropic changes in crystal orientation fabrics.From measurements along the EPICA ice core, it is known that the crystal-orientaiton fabric (COF) changes from a vertical girdle to increased single-pole orientation around the depth of the reflector.Azimuthal orientation of ice-core segments is lost during retrieval.We use the orientation of RES reflection maxima of the observed reflector to locate the orientation of the girdle to lie in the vertical plane parallel to the ice divide.

Similar Items