Table of Contents
Journal of Geological Research
Volume 2016 (2016), Article ID 4292806, 11 pages
http://dx.doi.org/10.1155/2016/4292806
Research Article

Lidar-Based Detection and Interpretation of Glaciotectonic Features of the Morainic Topography of Finland

Soil Laboratory of Oulu City, PL 78, 90015 Oulun kaupunki, Finland

Received 26 April 2016; Revised 6 September 2016; Accepted 12 October 2016

Academic Editor: Karoly Nemeth

Copyright © 2016 Matti Veli Juhani Seppälä. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In Finland’s digital elevation model, marks of glaciotectonics as an important formation process of glacial geomorphology can be seen. This is a new finding to this extent regarding central parts of the former ice sheets. Deformational processes produced fragmented till surfaces probably mostly by brittle fracture of frozen till. Good signs of deformational effect to the till surfaces are the plucked edges or steps and semilinear or fan-like quarry edges in topography, which are often oblique compared with the main direction of the flow of the glacier. Plucked fractured steps of blocks of till can be so tight that they construct horizontal-like diamond patterned surfaces. Sometimes punctate proximal endings of fan-like hollows of transported rafts can be seen. Within main ice lobes or streams the glaciated terrain is often divided into longitudinal smooth looking drumlin terrain and into rough erosional slightly lower level situated zones, where the erosion has happened firstly by glaciotectonism and then by glaciofluvial streams. The eskers and different kind of hummocky moraines are often located in same zones. Among them deformational hummocky moraines and ribbed moraines are common. The abundance of glaciotectonic and plucking related features indicates that the base of the receding ice sheet was cold based in places or from time to time.