New precision instrument for the GFZ

08.03.2013 | Potsdam: On 8 March 2013 a new secondary ion mass spectrometer (SIMS) will be delivered to the GFZ German Research Centre for Geosciences. The bulky device is divided into seven parts and transported as a heavy load. The apparatus weighs 10 tons but is used for high-sensitivity measurement of lightweights. Secondary ion mass spectrometry is one of the most important micro-measurement methods in the geosciences and is used to determine the concentration of trace elements.

Ions are first fired onto the surface of a polished sample in a vacuum. This leads to material of this surface being removed, which is partially ionized again. These secondary ions are analyzed in a mass spectrometer. The achieved detection accuracy is enormous: Out of ten million atoms the SIMS can identify a single one. This allows, for example, the determination of tiny trace amounts of precious metals, with which the formation of mineral deposits can be studied. This information can help find new raw material deposits.

The GFZ operates a SIMS laboratory since 1998, which is available to scientists from around the world on cooperative basis. More than one hundred projects with scientists from 22 countries were conducted here in the last 13 years. The new machine, which will be about 20 times faster and five times more accurate in the measurement of geologically important chemical systems, was purchased to considerably improve the range of metrological possibilities. It will be possible, for example, to precisely measure isotopic ratios of oxygen with an accuracy of less than one part per 5000 with a sample volume of less than a billionth of a gram. This previously unattainable data quality is required to explore various important issues such as the climate change or the creation of the continents, because these processes leave traces that need to be examined with investigative accuracy.

With the initiation of the new equipment, which is expected in July 2013, the Helmholtz Centre in Potsdam is thus the fourth location in the EU and the first in Germany to have this technology for the geosciences installed. Twenty project requests have already been received.