Nestled in the remote Sakha Republic of the Russian Far East, the Batagay crater, also known as the ‘Gateway to the Underworld’, is a colossal, expanding scar on Siberia’s frozen landscape. This remarkable geological formation offers a window into the Earth’s ancient past, revealing layers of permafrost that have been frozen for up to 650,000 years – the oldest in Siberia and second oldest globally, after relict ground ice in Canada’s Yukon Territory.
The crater, officially called the Batagay (or Batagaika) crater or megaslump, formed in the 1970s when a portion of the hillside in the Yana Uplands collapsed. However, it wasn’t discovered until 1991 when satellite images revealed a towering cliff face overlooking a massive depression in the frigid landscape. Today, the Batagay crater stands as the largest megaslump in the world, measuring 3,250 feet (990 meters) wide and sporting a 180-foot (55 m) high cliff face, known as the headwall.
The crater’s expansion is a testament to the effects of climate change. It grows annually by about 35 million cubic feet (1 million cubic meters), exposing new layers of ancient permafrost. The headwall is also retreating at a rate of 40 feet (12 m) per year due to permafrost thaw, releasing significant amounts of ice and sediment into the crater. This melt material eventually washes into the Batagay River valley at the end of the formation.
The permafrost in this region, consisting of 80% ice, likely contributed to the initial hillside slump. Deforestation in the area starting in the 1940s further accelerated the process. The removal of topsoil exposed the underlying permafrost, which melted more rapidly than if it had been richer in sediments. This accelerated melting led to the disintegration and collapse of the hillside, creating the iconic ‘Gateway to the Underworld.’
The Batagay crater is more than just a geological curiosity. Its exposed permafrost layers are a goldmine for paleoclimate research, providing valuable insights into past climates. As there are few accessible ancient permafrost layers in Siberia, the Batagay megaslump offers a unique laboratory for scientists. The crater also provides a glimpse into ancient animal and plant life. In 2018, researchers unearthed an intact, 42,000-year-old Pleistocene horse foal, frozen in time within the megaslump’s headwall. While older permafrost layers may not contain such well-preserved specimens, they hold the promise of ancient DNA, offering a rich tapestry of life from the distant past.
The Batagay crater stands as a stark reminder of the impact of climate change and a unique window into the Earth’s frozen history. As it continues to expand, revealing new layers of ancient permafrost, it promises to keep scientists occupied for generations to come, unraveling the secrets of a long-gone world.
