This is a position by position, team by team breakdown of how teams propsect depth chart looks. Red is good, Green is bad. These are totals. It doesn't show how many from each position are included, that is in the second picture.
This is how many players at each position are included in the above totals. It shows that the Mariners are deep at SS while they really only have Brad Miller and Carlos Triunfel but 5 others are counted due to the season they had. It isn't a perfect system but it is a visual representation of where teams stand for the most part.