The game is absolutely gorgeous, it's incredible how much you did with such simple graphics.
However, mechanically it is very lacking. The sonar mechanic serves no purpose other than blinding you at the worst time when you're dodging a moving obstacle.
The player hitbox is immense, making sneaking through narrow passages impossible. There are often times you think you can squeeze between a mine and the terrain just to be dragged by your hitbox to hit the mine.
There are several background features that look exactly the same as the level walls, making it guesswork to figure out whether you can pass through a black spot or not.
I found it very easy to get lost, there is no way to know which way is "forward", if you're making any progress or what.
There is potential, especially being a jam game, and these issues can be very easily fixed and improved upon. Keep it up! Focus on the making the core mechanics, moving and sonar, feel good to use.