Terrestrial history of the Muonionalusta iron meteorites


Project leader


Funding source

Swedish Research Council - Vetenskapsrådet (VR)


Project Details

Start date: 01/01/2005
End date: 31/12/2008
Funding: 810000 SEK


Description

The Muonionalusta irons have been found in the northern part of the Pajala District, Norrbotten County, where they occur scattered in glacial and glaciofluvial deposits. It is generally accepted that the parent meteoroid ruptured in the atmosphere in Middle Pleistocene and fell as a shower over a large area that later became part of the most well preserved landscape in northern Sweden, where glacial erosion has been very weak. This is supported by a large number of new meteorites discovered in recent years. The terrestrial residence of Muonionalusta represents a rare case where iron meteorites have been subjected to repeated cycles of glaciation-deglaciation and survived weathering for > 100 ka under periodically sub-humid conditions. Within this interdisciplinary project, we want to establish an absolute chronology for the fall and subsequent redistribution processes, by determination of cosmogenic nuclides (36Cl, 26Al, 10Be) in meteorites and in boulders in the sedimentary units associated with meteorite finds. Fieldwork, including systematic searches of meteorites in key areas, is an essential part. The areal and stratigraphic distribution of meteorites will be used to reconstruct Quaternary glacial and fluvial processes. In addition we want to use diffraction and spectroscopic methods to determine the chemical-structural nature of secondary minerals formed during meteorite oxidation and investigate the relations between environment of deposition and weathering rates.


External Partners


Last updated on 2017-31-03 at 12:57