The search of the depth — i.e., the secret recesses of it. The “springs of the sea” are rather, perhaps, the mazes, intricacies, &c. of the trackless, pathless deep. This leads to the cognate thought of the bottomless pit of death (Job 38:17).
Related Commentaries of Job 38:16
Job 38:16
16 Hast thou entered into the springs of the sea? or hast thou walked in the search of the depth?