How Deep is Permafrost Collapse

Just how deep are these permafrost collapse lakes? And how much preserved organic material are they releasing? Viruses can live for a million years in ice. Permafrost accumulates at about an eighth or sixteenth of an inch per year and can be a half mile thick in North America and a mile thick in Siberia. There are 5 billion acres of permafrost and 1.2 billion are at immediate risk of or are currently in collapse. It takes 289 times more heat to melt ice from 32 to 33 degrees, than it does to change the temperature of ice one degree from say 28 to 29 degrees. This is called the heat of fusion. Once ice crosses this 289 times tipping point, collapse occurs and it can be extremely widespread.