Linear features on karst surfaces: an example from Krk Island

Abstract

Krk Island located in the Dinaric karst is characterized by somehow contradictory, yet undefined depressions of linear geometry. A comprehensive spatial analysis considering over 900 linear features has served as a testing ground for revealing the specific circumstances required for the occurrence of linear morphology on the surface of rather pure karst typically characterized by dolines. Morphologic characteristics, spatial distribution and direct field evidence imply that linear features of different appearance are the outcome of, to the different stages reshaped, karstified, lithologic and tectonic structures. Due to specific regional climate conditions, they have been subsequently modified by the sporadic, fluvial processes of different degrees of intensity. Recently, such linear features hold dry valley- or dry gorge-like appearance. This example from the Dinarides gives the insight into possible circumstances that may cause a temporal surface runoff and consequentially result in the existence of an apparent fluvial surface morphology even in rather pure karst conditions. This knowledge is valuable for understanding other karst areas expressing temporal fluvial activity or imprints of past fluvial processes.