The Occurrence of Adsorbed Tight Oil and Its Effect on Porosity and Permeability Reduction of Triassic Lacustrine Sandstone Reservoir

Figure 2

Typical pore types found in the tight oil sandstone samples. (a) Residual interparticle pores coated by chlorite (B280-13-3). (b) Chlorite and residual organic matter dominate the residual interparticle pores (B436-7-38). (c) Residual interparticle pores with feldspar dissolution (B455-2-46). (d) Interparticle pore and feldspar dissolved pores (B436-7-33). (e) Interparticle pore and calcite cementation, residual interparticle pores filled with adsorbed organic matter (B455-2-60). (f) The intergranular pore and feldspar dissolved pore filled with adsorbed organic matter (B456-6-6) (Q: quartz; F: feldspar; Ca: calcite; Ch: chlorite; P: pores).

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(b)

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(f)