Yes, you can grab the goodies on both sides with some effort.
As you enter, facing into the canyon, you'll see two ledges on either side, right & left. The first grab on the left is a short climb up to where some beer bottle are, etc. On the right look for an arrow on the rocks and jump up onto the ledge with the help of small rocks. After you nab the feltrite you need to keep climbing up. Move forward and hit jump if I remember correctly.
You'll come to a clearing at the top and a bit of room which you need to get a running start and jump across the gap to the other side. To make the jump use sprint, then jump and you can make it across, if you miss try again. Nab the last items here.