Morphometric measurements of cinder cones from digital elevation models of Tolbachik volcanic field, central Kamchatka

Abstract

The present research examines the measured morphometric values of monogenetic cinder cones in the Tolbachik volcanic field, Kluchevskaya volcanic group, Kamchatka. The cones were measured from digital elevation models (DEMs) derived from satellite data (ASTER, ALOS PALSAR, and SRTM) and from digitized topographic maps. GPS measurements of 85 locations were performed in the field to provide geodetic reference for DEM processing and to assess the accuracy of the DEM. A methodology for morphometric measurements on a DEM is proposed. The morphometric parameters derived from a DEM include the main characteristics that control the rate of degradational evolution of the cone, namely height, width, and slope. The measured morphometric values were compared and accuracy assessment was carried out. Our study analyzes the morphometric values of four recent cinder cones formed during the last basaltic eruption in 1975–1976 and five older cinder cones formed during the last 2000 years. We show that morphometric values obtained from a DEM are affected by the resolution change, and characteristics of the same cinder cone may vary among DEMs of different resolutions. Our results indicate that the morphometry of the cinder cones can be well characterized by a DEM derived from remotely sensed data. The calculated morphometric parameters showed a correlation with the spatial resolution of the DEM and relative age of the cinder cones. All DEMs studied (including coarse-resolution SRTM) were found to provide reliable morphometric parameters, although the calculated values varied as a function of spatial resolution.