On the example of the Rita River delta and alluvial fan of the Shartlai River located on the northwestern coast of Lake Baikal, we show the possibilities of ultra-detailed aerial photography, which allows tracing surface discontinuities with displacements from a few centimeters. The software package “Agisoft Metashape” was applied for analyzing the multi-temporal digital elevation models with the same spatial resolution of 1,67 cm/pixel to fix possible changes in the earth’s surface over the year for the local area of earthquake-induced ground failures at Cape Rytyi. It has been established that most of this part has sunk by an average of 5–10 cm per year, and in the axial parts of the faults, subsidence has reached 33 cm. The greatest accumulation of sediments (up to 40 cm thick in some places) occurred on the shore, which is mainly due to the geological activity of the waves of Lake Baikal. Based on the relationship between ruptures and alluvial fans of different ages, we concluded at least two rupturing paleoearthquakes at Cape Shartlai. On the author’s geoportal “ActiveTectonics”, we uploaded some materials of unmanned aerial photography and geological objects in the form of orthophotomaps, digital elevation models and 360° panoramas that significantly expands the possibilities of data perception which are the basis for scientific results and conclusions.

Oksana V. Lunina
Doctor of Geological and Mineralogical Sciences,
Principal Researcher
Tectonophysics Laboratory, Institute of the Earth’s Crust, Siberian Branch of Russian Academy of Sciences
128, Lermontova Str., Irkutsk, 664033, Russia
е-mail: lounina@crust.irk.ru
ORCID: 0000-0001-7743-8877

Anton A. Gladkov
Candidate of Geological and Mineralogical Sciences, Researcher
Tectonophysics Laboratory, Institute of the Earth’s Crust, Siberian Branch of Russian Academy of Sciences
128, Lermontova Str., Irkutsk, 664033, Russia
Center for the Development of Continuing Education of Children,
Ministry of Education of Irkutsk Region
5/6, Sergeeva Str., Irkutsk, 664043, Russia
е-mail: anton90ne@rambler.ru
ORCID: 0000-0003-4235-6745

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