Researchers have uncovered a prehistoric terrain in East Antarctica, perfectly preserved beneath nearly two kilometers of ice for an estimated 34 million years. This significant finding, detailed in the journal Nature Communications, provides an unprecedented view of the continent before the onset of its current, massive glaciation period. The discovery illuminates a vastly different Antarctic realm that existed prior to this major climatic shift.
Utilizing advanced data from the Canadian satellite RADARSAT, scientists digitally mapped a surface area covering 32,000 square kilometers, comparable in size to Wales. This detailed cartography revealed a complex, preglacial topography featuring fan-shaped valleys, sunken mountain ranges, and deep fjords plunging almost 1,500 meters. These features strongly suggest the former presence of powerful, ancient river systems that once sculpted the landscape millions of years ago.
This 'lost world' serves as a critical time capsule, retaining climatic, vegetative, and hydrological signatures from a pivotal moment in Earth's history. The landscape was sealed away precisely as the planet began a significant cooling trend, marked by the transition between the Eocene and Oligocene epochs approximately 34 million years ago. This transition involved a critical decline in atmospheric carbon dioxide, which triggered the massive glaciation event.
The mapping effort identified three major elevated landmasses, designated Highland A, where fluvial erosion created the intricate, branching valley systems. Understanding how this ancient topography survived such extreme conditions for eons offers crucial insights into the future stability of the Antarctic ice sheet amid contemporary global warming. Furthermore, the ancient bedrock topography is now understood to potentially influence modern ice flow dynamics, meaning the past landscape subtly affects how the ice sheet behaves today.