Middle and Late Holocene landslides on the northern slope of the Aibga ridge

Abstract

When studying landslide processes, researchers pay great attention not only to the geometric dimensions of landslide bodies, displacement mechanisms, geomorphological features and reasons for their activation, but also to the time of their activation. The data obtained by radiocarbon dating of organic material selected from various geomorphological elements of landslides in the upper reaches of the Mzymta river basin (Western Caucasus) with a large sample of samples allow us to confidently say about the age of the event, or several episodes of landslide formation, the frequency of repetition of the process, as well as to establish the trigger causes that triggered the landslide. To obtain more reliable definitions of the age of the landslide, a method for performing serial selection of organic matter has been developed. Organic material was selected from various elements of the landslide : a) from sections of depressions in the rear part of the landslide, b) from sections of depressions on the main body of the landslide, c) from the humus horizon buried under the lingual part of the landslide. More than 40 new dates of samples of organic material have been obtained. The chronology of late- and Mid-Holocene landslides in the valley of the Mzymta river has been performed: 1. Landslides located on the northern slope of the Aibga ridge were formed during two major stages of landslide formation; 2. The older stage of landslide formation dates from the Middle Holocene from 6310 to 5380 cal. 3. The relatively younger stage of landslide formation dates from the Middle Holocene from 2930 to 2820 cal. years ago.