SCORIA CONES AS TECTONIC, CLIMATE, AND EROSION MARKERS: MORPHOMETRIC ANALYSIS OF EREBUS VOLCANIC PROVINCE, ANTARCTICA, USING HIGH-RESOLUTION DIGITAL ELEVATION DATA

Morphologic study of dated cinder cones in the Erebus Volcanic Province, Antarctica, is used to establish an age-calibrated rate of surface change in a polar desert environment. A relative age classification based on the degree of cone slope degradation can be used to assign ages to the hundreds of undated cones in Antarctica and may prove applicable as a dating tool for volcanism in other cold-desert environments, such as those on Mars and other terrestrial planets. Cinder cones provide ideal subjects for this analysis because they form consistently as simple, radially symmetrical landforms with approximately constant slopes.

Polar desert environments are generally presumed to have minimal effects on landscape change and polar dry-based glaciers are considered to be ineffective agents of erosion. This study tests these presumptions by documenting the signature of dry-based glaciation on cinder cones and by determining an erosion rate for polar-desert environments from diffusion modeling of degrading cones. Differences in erosion rates beneath polar and polythermal glaciers can be established using these results and the conclusions of previous authors.

The principal methods applied are quantitative morphometric analysis and modeling using ArcGIS tools with digital elevation models (DEMs) derived from Airborne Laser Scanning (ALS) data and high-resolution stereo satellite imagery. DEMs are used in tandem with satellite images to characterize landforms and surface properties of both glaciated and nonglaciated polar-desert volcanic terrain.