The AAPG/Datapages Combined Publications Database
AAPG Bulletin
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AAPG Bulletin; Year: 2018; Issue: September DOI: 10.1306/0108181613217061
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Figure 6. Photomicrographs showing sedimentary and diagenetic minerals in studied tight sandstones. (A) Plane-polarized light (PPL) image showing sandstone compositions. Particle composition was mainly composed of quartz (Q; 34.0%) and feldspar (F; 23.5%). Rock fragments (RF) include igneous (extrusive rock only: 5.7%), metamorphic (including Q, schist, phyllite, and slate: 18.5%), and sedimentary RF (mica only: 1.8%) (EY37, nitrogen permeability [kg] = 0.082 md, porosity [φ] = 7.63%). (B) A PPL image showing clay minerals attached to the surface of the pore and throat (EYU28, kg = 0.130 md, φ = 11.75%). (C) Scanning electron microscopy (SEM) image showing bent-sheet-shaped, flocculent mixed-layer illite–smectite (I/S) and illite (I) between rock grains and on grain surfaces (EYU28, kg = 0.130 md, φ = 11.75%). (D) An SEM image showing pore lining with leaf-shaped chlorite (Chl) and authigenic microquartz (AQ) filled in the intergranular pores (EY37, kg = 0.082 md, φ = 7.63%). (E) An SEM image showing filamentous I were filled in the throat (EH20, kg = 0.111 md, φ = 9.36%). (F) An SEM image showing intergranular plate-shaped and sheet-shaped kaolinite (K; EY38, kg = 0.105 md, φ = 8.38%). Ca = calcite.
Figure 6. Photomicrographs showing sedimentary and diagenetic minerals in studied tight sandstones. (A) Plane-polarized light (PPL) image showing sandstone compositions. Particle composition was mainly composed of quartz (Q; 34.0%) and feldspar (F; 23.5%). Rock fragments (RF) include igneous (extrusive rock only: 5.7%), metamorphic (including Q, schist, phyllite, and slate: 18.5%), and sedimentary RF (mica only: 1.8%) (EY37, nitrogen permeability [kg] = 0.082 md, porosity [φ] = 7.63%). (B) A PPL image showing clay minerals attached to the surface of the pore and throat (EYU28, kg = 0.130 md, φ = 11.75%). (C) Scanning electron microscopy (SEM) image showing bent-sheet-shaped, flocculent mixed-layer illite–smectite (I/S) and illite (I) between rock grains and on grain surfaces (EYU28, kg = 0.130 md, φ = 11.75%). (D) An SEM image showing pore lining with leaf-shaped chlorite (Chl) and authigenic microquartz (AQ) filled in the intergranular pores (EY37, kg = 0.082 md, φ = 7.63%). (E) An SEM image showing filamentous I were filled in the throat (EH20, kg = 0.111 md, φ = 9.36%). (F) An SEM image showing intergranular plate-shaped and sheet-shaped kaolinite (K; EY38, kg = 0.105 md, φ = 8.38%). Ca = calcite.