75 million years ago when dinosaurs still roamed the Earth, raging wildfires tore through Antarctica says a new study.
Cretaceous period (100 million to 66 million years ago) is considered as one of the warmest periods on Earth. Then Antarctica’s James Ross Island was home to a temperate forest of conifers, ferns and flowering plants known as angiosperms, as well as to dinosaurs. But it also had ancient paleo-fires burning the forests. The charcoal remnants left behind from those period was scooped up by scientists and studied.
The finding marks the first evidence on record of a paleo-fire on James Ross Island, a part of the Antarctic Peninsula that now sits below South America. The discovery is an evidence that spontaneous fires were common in Antarctica during the Campanian age (about 84 million to 72 million years ago).
For the new work, an international team of scientists analysed fossils collected during a 2015-2016 expedition to the north eastern part of James Ross Island. These fossils contained fragments of plants that looked like charcoal residue, which had weathered away over the past tens of millions of years. The charcoal fragments were small. The largest paper-thin pieces were just 0.7 by 1.5 inches (19 by 38 millimetres). But scanning electron microscope images revealed their identity. These fossils are likely burned gymnosperms, likely from a botanical family of coniferous trees called Araucariaceae, the researchers found.
Now, the researchers are looking for new records of paleo-fires in other locations in Antarctica.
“Antarctica had intense volcanic activity caused by tectonics during the Cretaceous, as suggested by the presence of fossil remains in strata related to ash falls,” the researchers wrote in the study. “It is plausible that volcanic activity ignited the palaeo-wildfire that created the charcoal reported here.”