Brisk walking and running intervals.?

I run 7mph incline(2) for 1-1 1/2 mile then i brisk walk incline(20) for half a mile then i lower the incline to 3 or 5, and sprint for 30 secs. Then back to 7mph for about a minute. And i do it repetitively til i burn 1200 cals. And that takes me about an hour. Is what im doing burning more fat than running on a flat terrain?