A roof fall occurred above anchor point on 2 west longwall headgate between crosscut 10-11. Fall was 50' L by 16' W & it varied from 15-20' H. It did impede travel on LW face. It didn't involve any compliance issues. LW stage loader was involved in the fall. No other 50.20 criteria applies. The accident was caused by a weakened roof structure due to a laminated rock transition.