Kill the Skaarj mediating nearby, collect the gear and head up the path through a narrow canyon, as it widens out you can see a bridge and what appears to be a statue of a Titan sitting in a chair. Take the Dispersion Pistol in front of the Titan to awaken it. When you’ve killed the Titan the bridge will be shattered, stand on the Titans chair to activate a trigger. Go to the remains of the bridge and a new one will slowly rise from the lava. Cross the bridge into a passage to the next level.