Can anyone edit my summary please?

On March 11 2011, [the populated country of Japan] was devastated by an atrocious earthquake followed by a calamitous Tsunami. The catastrophic 8.9 magnitude [shock wave] that the Earthquake exerted, annihilated 400 kilometres north-east of Tokyo[Name the province or area, don't say north-east of Tokyo]. It was very clear that this earthquake was the largest in decades due to the fact that it was 8000 times more powerful than the one that devastated Christchurch, New Zealand. [Some] citizens of Japan stood still in agony as they knew that their fate [was] going to be sealed while [others] fled. The tsunami rolled across the pacific at a depth of 24 kilometres and at a speed of 800km/h. The innocent lives met there sorrowful demise, despite their valiant effort for survival. It was disheartening that 300 people met their demise[ I wouldn't use demise again pick a different word like fate] and 500 people went missing. Large 10m waves obliterated farm land and swept cars, ships, and buildings away. The tenacious waves damaged many coastal communities after hitting Miyagi and Fukushima’s prefectures. Eventually the tsunami halted its path of destruction, but left scars on the plains of Japan. After witnessing this hazardous chaos, who knows if a natural disaster of this magnitude will occur again.