Table 1.
Modal analysis compositions of sandstones in the Pisha Sandstone.
| Sample No. | Monocrystalline quartz (Qm) | Polycrystalline quartz (Qp) | Total Quartz (Q) | Feldspar (F) | Lithic fragments (L) | Total lithic fragments (Lt) | Cement and matrix |
|---|---|---|---|---|---|---|---|
| Ermaying Formation | |||||||
| Emy1 | 54.9 | 2.9 | 57.8 | 33.3 | 8.8 | 11.8 | 23.1 |
| Emy2 | 35.7 | 8.9 | 44.6 | 48.2 | 7.1 | 16.1 | 8.7 |
| Emy4 | 33.3 | 28.6 | 61.9 | 38.1 | 0.0 | 28.6 | 21.6 |
| Emy5 | 74.1 | 11.1 | 85.2 | 11.1 | 3.7 | 14.8 | 39.5 |
| Emy7 | 48.8 | 7.0 | 55.8 | 26.7 | 17.4 | 24.4 | 17.1 |
| Emy9 | 44.2 | 20.9 | 65.1 | 23.3 | 11.6 | 32.6 | 33.3 |
| Emy10 | 33.3 | 1.9 | 35.2 | 37.0 | 27.8 | 29.6 | 29.6 |
| Liujiagou Formation | |||||||
| Ljg1 | 60.5 | 5.3 | 65.8 | 31.6 | 2.6 | 7.9 | 19.8 |
| Ljg2 | 67.6 | 2.9 | 70.6 | 14.7 | 14.7 | 17.6 | 20.6 |
| Average | 50.3 | 9.9 | 60.2 | 29.3 | 10.4 | 20.4 | 23.7 |