Væskeinklusjonslaboratorium

The Fluid Inclusion Lab at the Earth Science Department is primarily dedicated to microthermoetric analyses of fluid inclusions in stalagmites, i.e., the reconstruction of temperature-time series for paleo-climate research based on microthermometric measurements of liquid-vapour homogenisation temperatures. The lab is equipped with a Linkam THSMG 600 heating/freezing stage mounted on a Olympus BX51 microscope, and an amplified femtosecond laser system (CPA-2101, Clark-MXR, Inc.) coupled into the microscope.

The femtosecond laser allows us to stimulate vapour bubble nucleation in metastable, monophase liquid inclusions by means of single ultra-short laser pulses. Such monophase liquid inclusions are characteristic for stalagmites and other low-temperature carbonates and sulphates formed at near-surface conditions and stimulation of the vapour bubble nucleation is a precondition for subsequent measurements of the liquid-vapour homogenisation temperature. Moreover, femtosecond laser pulses can also be used to stimulate the nucleation of salt crystals in super-saturated brines and of salt hydrates at temperatures below the eutectic.

The application of femtosecond laser pulses is a highly efficient and elegant way to overcome metastable phase states in fluid inclusions. The experimental setup we are using allows us to repeatedly and reliably induce phase nucleation in selected fluid inclusions at different temperatures under microscopic observation and to perform subsequent microthermometric measurements without moving the sample. Room: 2G 7e (2156) phone: 83492

Listen to Anna Nele Meckler talking about the technique in the geological podcast Geologisk Rapport: