Research of gas-explosive objects in the upper part of the section using unmanned aerial vehicles. Article 2: Dedilovsky karst sinkhole

The article shows that the danger of karst formation in the upper part of the section is enhanced due to the frequent filling of karst cavities with gas at abnormally high pressure, generating gas-dynamic processes that destroy the roof of the cavity and lead to gas blowouts/explosions. The results of a four-year monitoring of the Dedilovsky karst sinkhole development in the Tula region (formed on May 8, 2019) using the DJI Mavic Pro unmanned aerial vehicle were presented, during which 12 multi-temporal aerial photographs were taken and 12 three-dimensional (3D) models were built in the period from May 18, 2019, until June 1, 2023. The maximum change in the sinkhole outlines along the surface of the earth in the northwestern directions was established at 6.4–7.8 m towards the residential building. It is shown that aerial photography of hazardous objects from unmanned aerial vehicle with subsequent photogrammetric data processing allows you to quickly create digital 3D models and study the ongoing geodynamic, geological and environmental processes.