TSE on Quantitative Characterization of Shale Reservoir

exploration, the success of North American shale oil and gas exploration and development, domestic oil workers has increased the focus on shale. In the past, shale is only in the sense of being as a source. The actual exploration and research indicate that shale can also reserve and filtrate fluid, as oil and gas reservoirs. So, it is particularly important for shale to quantify characterization of reservoir space. At present, there are mainly three ways for shale to quantify reservoir characterization.(1)Image analysis technology in micro-area;(2)Fluid injection technology dominated by mercury porosimetry and gas adsorption isotherm; (3)Non-fluid injection technology represented by magnetic resonance and computer tomography of smallangle Neutron scattering(Jiao et al,2014). The cryogenic nitrogen adsorption is the most common type of method characterizing mesoporous. But, during the research, it found that due to TSE, adsorption isotherms of adsorption and desorption curves appear on fake peak. It will affect quantitative characterization of shale reservoir porosity. This phenomenon caused a large concern of geologists. Correct reservoir characterization can effectively instruct exploration and development. This paper is based on oil shale samples from liaohe depression Bohai Bay basin. Firstly, high temperature vacuum pretreatment samples, then adsorbent with high purity nitrogen in 77.35K temperature to measure nitrogen adsorption under different relative pressure. Figure 1 is N2 adsorption and desorption isotherms in 77.35K. Desorption isotherm has been visible hysteresis at a higher P/P0. From the historiography and thermodynamics, this is due to the porous absorbing gases under high pressure and desorpting runder low pressure. It makes that the pore size distribution from desorption curve is more susceptible to influence of pore scale network than from adsorption curve. P/P0 emerges obvious power locks phenomenon in the vicinity of 0.41-0.48, which is caused by the desorption curve falling sharply. This phenomenon is called TSE(Johan C. Groen et al., 2003). Figure 2 is BJH pore size distribution curves obtained by N2 adsorption and desorption curves. From here we can see that, because of TSE, BJH pore size distribution obtained by desorption isotherm curve is absolutely different by adsorption isotherm curves. Without considering TSE, pore YIN Jianxin, LI Jijun and ZHANG Yanian, 2015. TSE on Quantitative Characterization of Shale Reservoir. Acta Geologica Sinica (English Edition), 89(supp.): 120-121.