mpec – Page 5 – Peč Lab

August 25, 2017August 28, 2017

Rig stiffness & heating test

We just finished a very successful 3 day long heating and rig stiffness test. The results were very consistent and show a loading stiffness of ~15 µm / kN at a range of temperatures (300˚C to 700˚C) at 0.6 GPa confining pressure. Since we currently operate only with one pressure vessel, we stay in the lower limits of the P-T space we can achieve to prevent pressure vessel failure and delays to our tests. Our main aim is to reach about 2 GPa confining pressure and 1150˚C – this will allow us to deform partially molten mantle rocks with a simple NaCl pressure medium.

Sample assembly after experiment – note the large grain size of the salt between the furnace (black) and sample (white Al2O3 piston in the center). Grain growth occurs over long time periods at high temperatures.

Results from the stiffness tests – note the inflection point at about 5 mm displacement, this corresponds to the hitting of the sample with the WC piston. The subsequent loading slope and unloading slope are used to asses the rig stiffness.

Furnace performance – Volts and Amps as a function of sample temperature. Initial peaks and oscillations are due to the search for right PID parameters in the Eurotherm controller. Shut off at ≈ 700˚C was used to estimate the maximal quenching rate – control was recovered at ≈400˚C. The maximum power our heating system can deliver is 500 A and 10 V which is enough to probably melt even the pressure vessel…

August 21, 2017August 22, 2017

New paper out

A new paper “Reaction Infiltration Instabilities in Mantle Rocks: an Experimental Investigation” got just published in the Journal of Petrology – check it out!

August 19, 2017September 1, 2017

Lab visits

Matěj had an opportunity to visit two other labs where the next-generation solid medium apparatus is installed – one in ISTOrléans and the other one ENS in Paris. It was great to exchange tips and tricks we learned so far. A big thank you to Jacques Précigout in Orléans and Alex Schubnel and Julien Fauconnier in Paris for their hospitality!

Jacques and his rig in Orléans

Alex and Julien and their rig in Paris.

August 14, 2017August 11, 2017

Goldschmidt

Matěj will deliver a keynote talk entitled “Experimental Insights on Reactive Melt Migration in the Upper Mantle” at Goldschmidt conference in Paris. If you are around, come and see the talk on Thursday, August 17th at 16:30 in session 07e – “Diffusion, deformation and transport processes in geomaterials”.

August 2, 2017August 11, 2017