Shapes of Things: Specific Geomorphometry of Cryoplanation Terraces in Eastern Beringia

Keywords: Beringia, cryoplanation, periglacial, specific geomorphometry
Abstract Type: Poster Abstract

Abstract

Geomorphometry, the quantitative study of the land surface, lies at the intersection of mathematics, geosciences, and computer science. The subject is divided into two distinct categories: “specific” and “general”. Specific geomorphometry is the study of individual (discreet) landforms with common origins or morphological characteristics, while general geomorphometry investigates and characterizes the continuous land surface. Recent work on cryoplanation terraces (CTs) concluded that, on the basis of general geomorphometric analysis, these landforms can be regarded as the foundation of many upland periglacial landscapes in eastern Beringia. It follows that investigation into the geomorphometric signature of the upland periglacial landscape cannot be considered complete without specific geomorphometric analysis of cryoplanation terraces. However, despite known variations in CT morphological attributes and size, the definition of a cryoplanation terrace has been addressed primarily through qualitative verbal description. In this presentation we discuss the application of specific geomorphometric methods to series of cryoplanation terraces in several widely separated localities of eastern Beringia. The increasing availability of high-resolution DEMs facilitates the creation of quantitative definitions of individual landforms, which can in turn be used in geomorphometric analysis. In this presentation we report statistical treatments of CT scarp and tread dimensions, slope angles, orientation, and topographic position. These measures reinforce the concept of a characteristic upland periglacial landscape.