Figure 1. These photos show the site that inspired this article. They were taken in November, 2011, at a bedrock outcrop on Clarry Hill in Union. Figure 1A was taken late in the afternoon, with the sun low in the western sky. It shows weathered but clearly visible glacial grooves carved by ice flow to the south-southeast (158-166°; toward the foreground). I revisited this site two days later, under cloudy conditions, and found the grooves were indistinct and almost invisible (Figure 1B).
Last updated on July 9, 2012