You will see these rippled marks on these rocks that were shoved up by the Lewis Thrust. These rocks were once at the bottom of the Belton Sea. "Think in terms of a really shallow area with ripple marks formed on the bottom - you have probably seen these at the beach near shore. Then, a change of some sort takes place and fine sediment is laid down on top of the ripple marks. Then, the whole works gets deeply buried and turns to rock. When the rock becomes exposed and weathered, the rock formed from the fine sediment that covered the ripple marks is weathered away more quickly, leaving the nicely preserved ripple marks behind. Not really large enough to be called wave marks."

And you can also see the outhouse ahead; had to be hard to close the door to that view. Sherburne Lake in the distance.
Here is some more of the story about GNP's geology: https://www.nationalparkreservations.co ... verthrust/