Accessibility of Pores to Methane in New Albany Shale Samples of Varying Maturity Determined Using SANS and USANS

Autor: Tomasz Blach, Andrzej P. Radlinski, Phung Vu, Yeping Ji, Liliana de Campo, Elliot P. Gilbert, Klaus Regenauer-Lieb, Maria Mastalerz
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Energies, Vol 14, Iss 24, p 8438 (2021)
Druh dokumentu: article
ISSN: 1996-1073
DOI: 10.3390/en14248438
Popis: The accessibility of pores to methane has been investigated in Devonian New Albany Shale Formation early-mature (Ro = 0.50%) to post-mature (Ro = 1.40%) samples. A Marcellus Shale Formation sample was included to expand the maturation range to Ro 2.50%. These are organic matter-rich rocks with total organic carbon (TOC) values of 3.4 to 14.4% and porosity values of 2.19 to 6.88%. Contrast matching small-angle neutron scattering (SANS) and ultra-small angle neutron scattering (USANS) techniques were used to generate porosity-related data before and after pressure cycling under hydrostatic (in a vacuum and at 500 bar of deuterated methane) and uniaxial stress (0 to ca. 350 bar) conditions. Our results showed that the accessible porosity was small for the samples studied, ranging from zero to 2.9%. No correlation between the accessible porosity and TOC or mineralogical composition was revealed, and the most likely explanation for porosity variation was related to the thermal transformation of organic matter and hydrocarbon generation. Pressure caused improvements in accessible porosity for most samples, except the oil window sample (Ro = 0.84%). Our data show that densification of methane occurs in nanopores, generally starting at diameters smaller than 20 nm, and that the distribution of methane density is affected by pressure cycling.
Databáze: Directory of Open Access Journals
Nepřihlášeným uživatelům se plný text nezobrazuje