November 2, 2016 - For an ExxonMobil-funded study, Oak Ridge National Laboratory chemists helped characterize shale that holds onto methane gas tightly. Conducting the first direct measurements of methane density in tight shale, the researchers used small-angle neutron scattering to study features smaller than 10 nanometers—a plethora of petite pores produced when hydrocarbons “cooked” and matured to make methane. The large surface area of small pores means gas molecules have lots of places to which to stick. Consequently, the researchers found methane was twice as dense in pores less than four nanometers wide compared to larger pores. “A better understanding of where gas is inside these tight shales will translate to better modeling and better understanding of extraction processes,” said Gernot Rother, who set up pressurized neutron scattering experiments with ORNL colleague David Wesolowski.