Good Morning, 

Thank you for contacting the U of M Extension Service. 

I am wondering if your tree is actually an oak tree? The leaves around the base appear to be maple leaves, and the bark is rather smooth to be an oak. 

This appears to be a case of sunscald. Please click on the following link: https://extension.umn.edu/planting-and-growing-guides/protecting-trees-and-shrubs-winter#sunscald-1263860

This information states: 

Sunscald happens when there are elongated, sunken, dried or cracked areas of dead bark, usually on the south or southwest side of a tree.

On cold winter days, the sun can heat up bark to stimulate activity. When a cloud, hill or building blocks the sun, bark temperature drops rapidly, killing the active tissue.

Trees susceptible to sunscald

• Young trees, newly planted trees, and thin-barked trees (cherry, crabapple, honey locust, linden, maple, mountain ash, plum).

Your tree should be able to heal from the wound. I would not put anything on the wound. If the bark had been wounded all around the tree, it may not survive. But I think your tree will heal and survive. 

Here is another link that discusses tree care: https://extension.umn.edu/how/planting-and-transplanting-trees-and-shrubs#mulching-1401311

You could add some wood mulch, a few inches away from the trunk, out around the tree for several feet. The mulch would protect the roots, keep the soil moist, and eliminates damage from mowers. This would help your tree heal from the wound. 

Good Luck!