Depending on their composition, oil shales have been divided into three categories: carbonate-rich shale, siliceous shale and cannel shale.
These three categories are carbonate-rich shale, siliceous shale and cannel shale. Depending on their composition, oil shales have been divided into three categories.
Depending on their composition, oil shales have been divided into three categories. These three categories are carbonate-rich shale, siliceous shale and cannel shale.
Depending on their composition, oil shales have been divided into three categories. These three categories are carbonate-rich shale, siliceous shale and cannel shale.