I remember how astounded I was a few years back when I read the report that they had found chemosynthetic bacteria in solid bedrock something like 25 hundred feet down.
I imagine that limit itself has been exceeded, next they will find chemosynthetic pyrophilic ones even deeper.
"Bacterial spores have recently been brought to public attention, following the use of these organisms for warfare purposes and the exciting report of viable 250-million-year-old spores (35).