| It was also postulated that the slow settling of organic material from the surface produced the bituminous carbonate layers known as oil shale. |
| Beneath the main White Stone Band there is an interval of mudstone and bituminous mudstone with a further thicker oil shale. |
| Carbonaceous shale, including oil shale, occurs in beds of clayey to silty mudrock from 0.3 to 3 m thick. |
| The biggest problem with mining oil shale comes as a result of heating oil shale rock. |
| I happen to be a supporter of exploiting the oil that's in Alaska and oil shale that we can exploit in Canada and in the States. |
| Shell Oil is working on a process that would heat the oil shale in place, which could have less effect on the environment. |
