Ground penetrating radar data collected from the Shackleton Ice Shelf, December 2023

Full description

Ground penetrating radar (GPR) is an active geophysical technique that uses high frequency radio waves to map the subsurface. The basic principle of GPR measurements is the transition of electromagnetic pulses of suitable frequency down into the ground through a transmitting antenna, and to detect the reflected energy as a function of time, amplitude and phase from any subsurface targets through a receiver antenna. If the electromagnetic travel velocity of the subsurface is known, time can be converted to depth. Wave reflections are generated from the boundaries of materials of different electromagnetic properties. The large contrast between the electromagnetic properties of rock, ice, water, and some sediments makes GPR a particularly effective method for mapping in frozen environments.

Data were collected with a Sensors and Software Pulse EKKO PRO system with a 100 MHz antenna and the high-power (1000 V) transmitter. The transmitter and receiver with a 1.5 m separation, were mounted on a non-metallic sled with cord and towing the sled on foot. The digital display unit was carried by and in view of the operator

Two common offset surveys were conducted on the Shackleton Ice shelf, at a walking pace of ~3 km h-1, with the aim of measuring ice shelf thicknesses at a prospective hot water drilling site on the floating ice, with the requirement of an ice thickness of ~200 m (constrained by time and drill depth capability). An initial survey of four ~500 m long profiles was conducted on 16th December 2023, two along the ice flow and two across flow. A second four profile survey was collected on 25th December 2023, roughly 130 m in length, to further refine the borehole location. The data can be viewed and processed in any standard GPR software.

.DT1 - binary raw data file
.GPS – GPS position file
.HD - Metadata file

Lineage

Progress Code: completed

Statement: The dataset is of good quality, no issues were encountered with collection or analysis.

Notes

Purpose
The ground penetrating radar (GPR) data were collected as part of the multi-disciplinary project funded by the Australian Antarctic Program Partnership and the Australian Antarctic Division, investigating the stability of the Denman Ice Shelf System, during the 2023-24 austral summer. The purpose of this project was to understand the key controls on the system’s stability, focusing on three governing processes that are known to influence ice shelf stability elsewhere. The purpose of the GPR data was to measure ice shelf thickness to refine the location of a hot water drilled borehole (~200 m thickness).