research

Analysis of meteorite samples using PIXE technique

Published in Journal of Radioanalytical and Nuclear Chemistry (2019) 322:1897–1903

Two meteorite samples were analysed using the PIXE technique at the CENTA: Rumanová (Slovakia) and Canyon Diablo (Arizona, US).

The original finding of the Rumanová meteorite comprised of one 4.3 kg piece of stone with a density of 3.53 g/cm3, and dimensions of 18.5×14.0×12.5 cm3. A cut block from this material was analysed. Overall 30 positions (spots) in a mesh with 3 mm step were analysed across the Rumanová meteorite surface. Absolute concentrations of Fe, Ni, Cu and Zn were calculated using microanalytical reference materials from USGS (United States Geological Survey). The concentrations of iron, nickel, copper and zinc were calculated, and distribution maps were created.

The situation with the Canyon Diablo Arizona meteorite sample is more complex since the original material was enormous comparing to Rumanová meteorite. The Barringer Crater (named in the honour of Daniel Barringer, who was first to suggest that it was produced by a meteorite impact) is approximately 1,200 m wide, 170 m deep and its age is 49 000 years. A small fragment (14 g) was analysed using the PIXE technique in the CENTA laboratory. The Canyon Diablo iron meteorite was analysed in 4 different positions. The determined concentrations are shown in the table together with an example spectrum of position #4 (the highest Cu and Zn values).

It has been found that inhomogeneities in the meteorite samples had the main influence on the distribution of the analysed elements, what is important information when using chemical composition of meteorites, e.g. for calculation of production rates of cosmogenic radionuclides.