Using multitemporal remote sensing data for evaluation of the Kuibyshev reservoir bank transformation (Laishevo and Ostolopovo archaeological sites, Tatarstan, Russia)

Abstract

The paper presents the results of studies of medieval archaeological sites, the Laishevsky and Ostolopovsky settlements, and the Ostolopovsky hillfort, using multitemporal remote sensing data and modern field research methods. The studied sites are located in the zone of active bank transformation and have been destroyed since the creation of the Kuibyshev reservoir. To assess the dynamics of the coastline, multitemporal remote sensing data were used. Shoreline positioning for the historical period of the 1950s was interpreted from archival aerial images (Kazan University Library). 1975 satellite images obtained during the Corona reconnaissance space program KeyHole-9 Hexagon satellite (10.06.1975). For their georeferencing very high-resolution satellite images were used (2019). The maximum errors of georeferencing are less than 3 pixels for both sites. In 2018-2019, field surveys of the shoreline fragments at the Ostolopovsky and the Laishevskoe settlements were carried out in 2020-at Ostolopovo hillfort placement. For field studies, a DJI Phantom 4 drone and GNSS receiver with real-Time kinematic corrections were used. The Digital Shoreline Analysis System (DSAS), as an extension module of the ArcGIS software, was used to quantify shoreline displacement. Shoreline indicators such as linear retreat rate (m/year), shoreline displacement (m) were automatically calculated. A quantitative assessment of the Kuibyshev shoreline transformation makes it possible to evaluate the damage caused to archaeological sites and the risk of their further destruction.