06/05/2017

Science Blog: Current Research Projects

Text:
Niko Putkinen, Geologist

GTK’s Geologist Niko Putkinen tells in this Science Blog text about his Current Research Projects.

Modern and Ancient Glaciations project

Niko has been collaborating in the utilization of new imagery (LiDAR) to shed new light on the origin of drumlins and megaflutings formed under soft-bedded glaciers. Following his postdoctoral year in the laboratory of Nick Eyles at the Department of Physical and Environmental Sciences, University of Toronto at Scarborough (UTSC) he has continued working with the erodent layer hypothesis (ELH) for the formation of mega-scale glacial lineations (MSGLs). The ELH describes megalineated terrains formed erosionally by an abrasion agent (erodent layer), which is typically a one-metre-thick active wet till layer that erodes the sediment or bedrock below. Maarten Krabbendam from the British Geological Survey (BGS) have previously joined the ELH team in research on mixed and hard-bedded glaciers. Understanding these glacial sedimentation processes has important implications for the mineral exploration of till sheets.

GTK’s ongoing Glacial Dynamics Mapping Programme is closely related to Niko’s scientific research. This project aims to map indicators of glacial dynamics, i.e. different moraine and glaciofluvial landforms, using LiDAR data. At present, a large group of researchers are mapping the numerical raw data across Finland. Simultaneously, a Finnish lithostratigraphical system (Finstrati) is being created that will be linked to geomorphological features. GTK has a significant contribution in this project, but the work is also linked to the research of J.P. Lunkka (U of Oulu) and Tiina Nikarmaa (PhD student, U of Oulu), as well as Joni Mäkinen (U of Turku) and V.P. Salonen (U of Helsinki).

Groundwater geology

Niko is involved in an ongoing project with local communities on the hydrogeological and hydrological characteristics of confined and leaky aquifers that will form the primary municipal drinking water source for the cities of Kurikka and Vaasa in the Pohjanmaa region of western Finland. This is the first large-scale groundwater investigation project on such aquifers in Finland. The groundwater resource exists in a deep ancient river valley that was covered by glacial sediments. Niko is currently evaluating the hydrogeological parameters of hydrogeological units and aquifers by means of long-term high-volume pumping tests. Environmental impacts during pumping are being monitored in a network of nearly 100 groundwater monitoring wells. In this project, Niko is collaborating with numerous GTK researchers, including Miikka Paalijärvi (responsible for water geochemistry), Nina Hendriksson (isotopes), Daniele Pedretti and Jarkko Okkonen (groundwater numerical and flow modelling), as well as Kirsti Korkka-Niemi at the University of Helsinki (responsible for surface water bodies).

Younger Dryas palaeoenvironments of Fennoscandia

Niko continues to work with Juha-Pekka Lunkka (U of Oulu) on the impact of the Younger Dryas climate shift on the glacier fluctuations of the Scandinavian Ice Sheet and on the variation in the level of the Baltic and White Sea ice lakes in Scandinavia and NW Russia during the course of the Weichselian deglaciation.

Simplified model for subglacial streamlined bedforms where a thin ‘erodent layer’ of deforming diamictic debris is swept across the substrate. Substrate heterogeneity results in higher-standing remnant ‘islands’ of stiffer bed material or former topographic highs that protrude through the thin erodent layer. The streamlined unconformity surface is progressively lowered and bedforms evolve from large (drumlins) to long (megaridges) bedforms with increased ice velocity as a consequence of cloning.
Niko Putkinen

Text: Niko Putkinen

Niko Putkinen (PhD) is a glacial sedimentologist in the Groundwater Unit at GTK. His current research interests are in glacial sedimentology and processes and their application in groundwater geology. Niko has spent years of his career in field research and is still impressed by the variety of sediments and deposits that were laid down by the fascinating power of the ancient continental ice sheet that repeatedly covered large areas of the Northern Hemisphere.