These features, they noted, are very similar to the geologic leftovers of the PETM and other hyperthermal events. (fortune.com)
The authors believe their research helps pin the cause of hyperthermals on long - term rhythms in the CO2 cycle for that 10 million year period. (earthtimes.org)
The similarities of these other hyperthermals with the PETM were taken as being suggestive of a common mechanism (s) giving rise to them all. (royalsociety.org)