Tectonic ledges at the Ladoga Lake bottom

For the past few years, the Institute of Limnology of the Russian Academy of Sciences has been conducting geological and geomorphological studies of the bottom of Lake Ladoga. Starting from 2018, underwater photo and video cameras developed at the Institute began to be used in these studies. The use of this new research tool led to the discovery of a number of new facts about the structure of the bottom of Lake Ladoga. In particular, at the bottom of the northern part of Lake Ladoga, three subvertical ledges were found, composed of bedrock, up to 70–100 meters high. According to a number of features, such as the bedrock composition of rocks, morphology and spatial correspondence to known fault zones, these ledges can be recognized as morphological expressions of tectonic objects – faults of presumably fault type. The absence of visible traces of glacial processing on the bedrock blocks suggests the Holocene age of the formation of these ledges and, accordingly, the existence of modern active tectonic movements in the area of Lake Ladoga.