Pore structure characterization of organic-rich Niutitang shale from China: Small angle neutron scattering (SANS) study

Abstract Pore structure can greatly impact the gas storage and flow mechanisms in shale reservoirs. Pore characteristics, including the pore (body/throat) size distribution (PSD), porosity, specific surface area, tortuosity, and connectivity, from four Niutitang shale samples were investigated with small-angle neutron scattering (SANS), mercury injection capillary pressure (MICP), and helium porosimetry to complement earlier gas (N 2 , CO 2 ) sorption and petrographic analyses. In particular, the SANS data provides information on the total porosity, including both the closed and open pores. The large-Q (scattering vector) “flat” background of the SANS data was used to estimate the volumes of pores with diameters of