Noble gas mass spectrometer

• Subject Area: Geology and Palaeontology
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 553672234

We propose installing a novel noble gas mass spectrometer at the ArgonLab at TU Bergakademie Freiberg. The new instrument would replace an old mass spectrometer, which is at the end of its life cycle. This action would ensure functionality of the laboratory for the next decades and massively expand possible study targets as recent technological advances allow for much higher measurement precision. Ar-Ar dating is a key method for radio-isotopic age determination as it makes use of the decay of a major element isotope. Hence, it allows dating of rock-forming minerals with a clear petrological significance such as mica, feldspar or amphibole. For a wide range of materials, K-Ar/Ar-Ar dating is the only or by-far preferred choice for absolute age determination. The method is typically used for dating volcanic rocks including basalt and for thermochronological studies (determination of cooling histories). Ar-Ar dating is laborious and requires fundamental technical and chemical/mineralogical expertise and support. Today, Ar-analyses are often outsourced and despite growing demand, there are only three functional Ar-labs left in Germany and the global number is shrinking. The ArgonLab at TUBAF has been a successful institution for nearly two decades performing its own method-oriented and regional research as well as cooperating with many colleagues in and outside Germany. It has excellent support with one permanent scientific position as lab manager and three permanently employed technicians serving all labs in our group. The lab is embedded in workshops in- and outside the group providing support in rock processing, sample preparation, and hard- and software engineering. The group of Endogeneous Geology/Tectonics at TU Bergakademie Freiberg is a large and interdisciplinary group with expertise in geochemistry, petrology, field geology, structural geology, thermodynamics, low-temperature thermochronology and mathematical modeling. In our group, we run several labs that allow for comprehensive material characterization (scanning-electron microscopy with EBSD- and EDX mapping facilities, Raman spectroscopy, extensive microscopical facilities). With a new noble gas mass spectrometer, we will take our regional studies to the next level but also start method-oriented research that depend on the precision of the new generation of mass spectrometers. We will for example approach the fundamental and controversial issue of closure temperature through a comprehensive field-based study design that makes use of our lab environment and our different skills.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Edelgas-Massenspektrometer
• Instrumentation Group: 1700 Massenspektrometer
• Applicant Institution: Technische Universität Bergakademie Freiberg
• Leader: Professor Dr. Thorsten Nagel