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

Figure 4

Photomicrographs of the main lithologies in the Lucaogou Formation, Jimusar Sag: (a) well J305, 3409.01 m, shell-rich dolomicrite with silts; (b) well J303, 2602.53 m, micrite containing abundant organic matter laminae; (c) well J301, 2779.27 m, argillaceous dolomite containing opaque (center) and clean (rim) dolomite, which is recrystallized into a granular texture; (d) well J303, 2595.5 m, dolomitic mudstone containing micritic dolomitic laminae; (e) well J305, 3554.54 m, dolomitic mudstone containing higher plant debris; (f) well J43, 2948.5 m, dolomite mudstone containing silt and abundant vitrinite (microspores); (g) well J305, 3568.51 m, tuffaceous mudstone with silt laminae; (h) well J251, 3786.61 m, dolomitic silty mudstone; (i) well J43, 2948.5 m, shale containing silt and organic matter laminations; (j) well J305, 3546.15 m, argillaceous siltstone; (k) well J303, 2594.8 m, argillaceous marly siltstone; (l) well J43, 2950.5 m, argillaceous siltstone (cross-polarized light); (m) well J303, 2576 m, dolomitic tuff; (n) well J305, 3546.15 m, tuff; (o) well J305, 3560.54 m, intermittent laminated tuffite.

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