I know lakers are at about 50' when the water is warm. But I was surprised to view the lake depths of Jean Lake and Cirrus from a post on the Quetico board where both lakes have large areas of subterranean real estate below depts of 100' and even 250'.

So finding 50' of water in these lakes isn't the issue. My understanding is that fish still prefer structure rather than wide open depth below them. Is that right? Is the key to locating LT finding not only depth but also nearby structure like humps or near shore and avoiding broad, deep basins?

Lake trout need cooler water so they go below the thermocline to find that water but...they also like food and there might not be much of that much below the thermocline.

Large northern pike also like cool water and on one of the lakes I fish, one that everyone knows has only small pike, I find the thermocline and fish at that depth which gets me some sizeable pike.

Structure can be one factor in fishing for Lake Trout, but it isn't the only thing to consider. During the summer I regularly troll over deep water where there is no structure (80-120 ft) and often catch them.

They don't need structure when they're in their deep summer areas. They're just looking for the right temps and move up or down to find them year-round.

If that magic depth one day is 60' yes they could be in 60' off the end of a nice point. Or they could be in 60' wandering in the middle of a giant basin that gets to 200' deep underneath them

When I look for structure for LT I am looking for steep cliffs. If you can find an area with 2 or better 3 walls these are best. They corral the bait fish in these areas.