Some Aspects to Develop Method for Determining the Open Porosity of Ultralow-Permeability Rocks on Crushed Core

Laboratory studies of shale formations face serious challenges, one of which is the development of methods to determine the porosity of ultralow-permeability rocks. As the object of study, more than 100 ultra-permeability different lithological composition core samples of the Bazhenov Formation were used. The paper presents the results of determining the open porosity of ultralow-permeability rocks of the Bazhenov Formation using two methods adapted for crushed core. This is a gas-volumetric method and a modified liquid saturation method. The paper shows the legitimacy of using the proposed methods to determine open porosity in sandstones by comparing the results on cylindrical samples and on crushed core. According to the results of the study, a methodology to determine the bulk density and grain density of ultralow-permeability rocks of the Bazhenov Formation was been completed. Also, a systematic error in determining the open porosity of ultralow-permeability rocks of the Bazhenov Formation by the standard method on plugs was also shown.