Shiveluch volcano 2012-2019 photogrammetric dataset

The helicopter surveys allowed us to acquire nadir and oblique aerial images collected during overflights on 12 July 2012 with Canon EOS 20D conventional digital camera (focal length - 14.183 mm, resolution - 3,504×2,336 px), and on 22 August 2019 and 22 October 2019 with PhaseOne IXA 160 digital aerial camera (focal length - 28 mm, resolution - 8,984×6,732 px). The average flying height was 4,000 m a.s.l. for the nadir survey and 3,200 m a.s.l. for the oblique survey. We performed the photogrammetric processing of the images in Agisoft Metashape 1.5.2. For interior orientation, we set the cameras’ parameters (focal length and sensor size). Relative orientation was performed automatically by the image alignment and tie points calculation. For the exterior orientation and ground control points (GCPs) assignment, we used coordinates taken from stable topographic prominences identified in the 1979 photogrammetric model, which is referenced to the USSR State Geodetic Network coordinate system. The total RMSEs of the aerial models’ orientation varies from 1.5 m to 2 m. As a result of processing, we obtained three aerial PCs with a 2 m average resolution, which were then filtered and cleaned in the same way described above. The gaps caused by the volcanic steam emissions and by the atmospheric clouds were closed by manual points collection using the anaglyph stereo mode of Photomod 5, which was performed by placing a floating mark on the visible surface and stores XYZ coordinates of each point. The aerial PCs had the same spatial scale as the Pleiades PC but were shifted in geo-position due to the different coordinate systems. To compare the PCs, we aligned the aerial PCs to the Pleiades PC with several points on the rim of the amphitheater using the CloudCompare alignment tool. The RMSEs of the alignment vary from 2.3 to 3.1 m. Thus, we obtained four stacked PCs in WGS84 UTM57 and were able to calculate differences between them. We outlined areas of the lava dome including the talus, separately for each date and calculated volumes between two consecutive PCs within these specific areas. We also acquired thermal infrared images of the lava dome by recording from a helicopter together with the optical survey before and after the 29 August 2019 eruption. On the first flight, we used a FLIR Tau 2 camera with a 9 mm lens and a TEAX ThermalCapture frame grabber set to a sampling rate of 8 Hz. The resulting images had a resolution of 640×512 px and provided radiometric temperature data. The images were processed and exported using Thermoviewer (v3.0.4), assuming a constant emissivity of 0.95, a transmissivity of 0.7 as well as environmental and path temperatures of 10 C°. For the second flight, we used a ThermaCAM P640 camera at a resolution of 640×480 px, exported and processed with FLIR Tools (v.5.13), assuming the same environmental parameters as before. Our set of photogrammetric data let us to explore the 2018-2019 eruptive events at Shiveluch in the frame of complex construction-destruction behavior, as well as the the influence of tectonic structural control on it's current activity.