Revisiting Controls on Shale Oil Accumulation in Saline Lacustrine Basins: The Permian Lucaogou Formation Mixed Rocks, Junggar Basin

Figure 6

Photomicrographs showing the reservoir space types in the Lucaogou Formation, Jimusar Sag: (a) well J10025, 3516.15 m, dolomitic mudstone with fractures; (b) well J303, 2600.31 m, dolomitic silty mudstone with bedding cracks filled with organic matter; (c) well J305, 3582.73 m, stylolites filled with organic matter (plane-polarized light); (d) well J43, 2947.45 m, calcareous siltstone with dissolution pores (plane-polarized light); (e) well J301, 2768.3 m, argillaceous dolomite showing iron dolomitization and dissolution and intercrystalline pores (plane-polarized light); (f) the same field of view as (e) but in cross-polarized light; (g) well J301, 2771.8 m, dolomicrite with abundant dissolution pores (plane-polarized light); (h) well J43, 2953 m, abundant intragranular pores in the veins of carbonate minerals, which are filled with organic matter (plane-polarized light); (i) well J10025, 3552.58 m, dolarenite with abundant dissolution and intergranular pores (plane-polarized light).

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