Noble Gas Thermochronometry Laboratory

This facility is specifically optimized for high-precision and high-accuracy (U-Th)/He and ⁴He/³He thermochronometry, although the system can be used to measure all five of the noble gases. The system is composed of an automated high-vacuum extraction system, a cryogenic noble gas purification system, a set of calibrated pipettes, a gas-source quadrupole mass spectrometer (QMS) for measuring noble gas abundances using isotope dilution, and a noble gas MAP-215 sector field mass spectrometer with ion counting electronics. A variety of feedback-controlled laser heating systems can be used to accurately measure temperatures during stepwise thermal extraction of noble gases from minerals and glasses over a wide range of temperatures. Complete system automation and instrument communications is achieved using software written in LabView. The design of our laser heating systems is such that they can be used with other systems optimized for cosmogenic ²¹Ne measurements or ⁴⁰Ar/³⁹Ar thermochronometry. A dedicated wet chemistry lab is used for dissolutions and isotope dilution.