Methodology:

The striated bedrock surfaces were observed and measured by Joanne S Johnson in 2019-20 on a geological campaign supported by British Antarctic survey logistics as part of the Geological History Constraints project (one of the component projects of the International Thwaites Glacier Collaboration). The data here pertain to their location and orientation. Locations (latitude, longitude and altitude) were measured using GPS. Orientations were measured using a hand-held Suunto compass.

Data collection:

The position (latitude and longitude, in decimal degrees) and altitude (metres above ellipsoid) were measured for each set of bedrock striations observed, using a Javad Triumph II GPS receiver. Files were processed on return to the UK. The heights above ellipsoid were corrected to orthometric heights (height above geoid EGM08 in metres above sea level) using Precise Point Positioning software [version 2]. Positional accuracy of the Javad Triumph II receiver is 0.010 m (horizontal) and 0.015 m (vertical).

The orientation of the striations in each set were measured using a hand-held Suunto compass and recorded as a magnetic bearing. Following return to the UK, each orientation was converted to a true bearing using the magnetic declination for the Hudson Mountains at the time the measurements were made (46 degrees E).