Table 1.
Bulk Phase Distributions and Crystalline Phase Abundances for the Oudam Sandstone and Marimba, Quela, and Sebina Mudstones Determined by FULLPAT and Rietveld Analyses, Respectively
| Bulk phase distributions | ||||
| Oudam | Marimba | Quela | Sebina | |
| Crystalline | 54 | 32 | 32 | 30 |
| Clay minerals | 3(1) | 28(3) | 16(2) | 19(2) |
| Opal‐CT | 7(1) | 0 | 0 | 0 |
| Amorphous | 36(9) | 40(10) | 52(13) | 51(13) |
| Total | 100 | 100 | 100 | 100 |
| Crystalline mineralogy | ||||
| Oudam | Marimba | Quela | Sebina | |
| Plagioclase | 52.3(11) | 44.3(30) | 43.6(33) | 37.9(22) |
| Hematite | 25.6(7) | 20.4(14) | 22.7(17) | 23.7(23) |
| Pyroxene | 8.1(17) | 2.2(19) | 7.3(19) | 6.9(38) |
| Anhydrite | 6.4(5) | 11.7(14) | 9.4(5) | 16.9(10) |
| Gypsum | 5.8(4) | 6.6(9) | 1.3(1) | 3.5(2) |
| Quartz | 1.8(4) | 1.7(6) | 1.1(7) | 0.9(2) |
| Sanidine | — | 7.5(18) | 6.5(13) | 4.2(13) |
| Bassanite | — | 3.9(10) | 5.9(3) | 3.5(2) |
| Jarosite | — | 1.7(8) | 1.4(5) | 2.5(5) |
| Halite | — | — | 0.8(2) | — |
| Total | 100 | 100 | 100 | 100 |
Note. Abundances in wt%; uncertainties reported as 1σ.