The Ar-Ar dating technique as it is practised today originated in the noble gas laboratory of John Reynolds in Berkeley, where Craig Merrihue and Grenville Turner were working on neutron irradiated meteorite samples using the I-Xe dating technique.

What is Ar Ar dating used for?

Potassium-argon dating, method of determining the time of origin of rocks by measuring the ratio of radioactive argon to radioactive potassium in the rock.