Its not as easy as that. Calories burnt also depend on you: your age, your weight, your body mass- the more you weigh, the more your body has to pull along, the more calories you burn. The lighter you are, the fewer calories you will burn (but the upside of that is most lighter runners are at an advantage: they have the chance to run faster as gravity is not as punishing so are able to burn even more calories by running faster.)
Its also (I think), dependant on how your energy levels are that day. I have days where I run at 11km/h and get my heart rate right up to 170 and it stays between there and 150bmp. Then I may have a bad day following and run at the same speed yet my system is so sluggish and my heart rate hovers between 130 and 150bmp. Whats more is it feels more exhausting so I am liable to stop alot earlier and burn less overall twice over. Its quite a difference and I'm not sure if anyone else gets this but I know I do.
I just go by my heart rate monitor- I am at odds weather or not to trust it (its a Polar) it tells me if I do yoga I burn about50-100kcals an hour yet when I do cardio I apparently do around 700kcals an hour. I workout for 1.5 tp 1.45 hours and am not really sure if the 1000kcal figure is correct and many others swear by their HRM to organise their food so I'd say take it with a pinch of salt and trust your instincts, you know how hard you work, not a guess work equation.