Those of the fluvial facies, especially the lacustrine facies and palaeosols, are mainly composed of very fine sands and also contain some quantities of silt and clay.
河流相、特别是湖沼相与古土壤以极细砂含量占优势，且具一定含量的粉砂和粘土。
2
The finer layers generally consist of carbonaceous clay, mild clay and silty sand, showing characteristics of lacustrine sedimentation.
细粒层均为含炭的粘土、亚粘土和粉砂，具湖塘相沉积的特点。
3
The geochemical characteristics of inclusion and clay-adsorbed oils correlate well with the lacustrine mudstones.