A trend-surface analysis of relief in Sipoo, southern Finland

Abstract

The spatial ordering of valley, mean and summit height features in an area of Archean bedrock is analysed by means of linear and quadratic trend surfaces and their residuals. The relief of this area, which slopes away towards the Gulf of Finland, is interpreted with special reference to bedrock composition, tectonic events and postglacial land uplift. Com­parison is made with a reference area surrounding the study area proper and extending to six times its size. The work, which emphasizes meth­odological aspects is based on the analysis of map data.

The surface of the area dips on an average in the direction 330° ‑> ­150°. The direction of maximum slope turns southwards at the coast, with a simultaneous increase in gradient. The summit level dips most steeply and the valley level least so. The dissected bedrock is character­ized by fault‑blocks differing in height and tilt.