I was exploring caves, on one of the treasure hunt quests, and found a large quantity of what looked like fallen rock, which highlighted when using Witcher Senses.
As shown in the image above, there was a symbol that showed up at the same time. I assumed that I should clear this, using either Aard or a bomb - but neither of these worked.
What does this symbol mean, and/or (vaguely related), how would I clear this rockfall?