Specialists from the Arctic and Antarctic Research Institute (AARI) examined unique permafrost formations on the Spitsbergen archipelago – giant hydrolaccoliths with ice cores. Using ground penetrating radar, scientists studied their structure and found out how they were formed.
In the Rheindalen Valley, scientists discovered a huge hydrolaccolith about 40 meters high. Its ice core raised a layer of coal from a depth of 75 meters, which indicates powerful geological processes. Scanning showed that such mounds are formed due to the freezing of groundwater that rises along faults.
Thousands of years ago, cooling began in this region, and groundwater, fed by melting glaciers, began to freeze. Gradually, the ice accumulated, creating pressure that lifted the rocks. In some cases, the ice even ruptured rock layers, bringing coal to the surface.
A special feature of the Svalbard hydrolaccoliths is the craters on their tops. They were formed due to the summer melting of ice, after which the soil subsided, forming depressions filled with water. Such thermokarst lakes are a rare occurrence.
“There are only a few tens of thousands of hydrolaccoliths on the planet, but only a few allow us to study the ice core using georadar,” explained AARI researcher Nikita Demidov. “Our research helps to understand permafrost processes, which is important for studying the permafrost zone of Russia.”
Getting to hydrolaccoliths is not easy – they are located in remote areas. To study the objects in Rheindalen, scientists traveled 80 km on snowmobiles. These studies will help better understand permafrost changes and their impact on climate.
Source: @aari_official
Photo: Oksana Kochanova, Alexander Novikov, AARI
