The Duvernay Formation is composed of laminated bituminous shale, calcareous shale and dense argillaceous limestone. The Blue Lias comprises decimetre scale alternations of argillaceous limestone and mudstone. The silty, argillaceous mudstones contain more than 30% silt-sized siliceous grains. The cementing material may be siliceous or argillaceous and is sometimes calcareous. Some clastic quartz sands and argillaceous layers. "Tuber" species prefer argillaceous or calcareous soils that are well drained and neutral or alkaline. Claystone and shales are thus predominantly argillaceous. The lithology comprised a combination of poorly lithified gray/blue claystone and black argillaceous sandstone. It also contains important subsidiary elements of silty and argillaceous material. Vaygach Island is mainly formed of argillaceous slates, sandstone, and limestone. The Ajabgarh Group is dominated by carbonate, mafic volcanic and argillaceous rocks. The limestone is white and argillaceous, and yielded an eminently hydraulic lime. It consists of thin blue argillaceous, or clay-like, limestone. Organic matter in the form of amorphous kerogen coats the argillaceous material. Shuichungliu Formation form the Oligocene contains argillaceous slate and graywacke.