Figure 2. Stratigraphic section at PTRM locality V89002. Grain size (clay, silt, and fine, medium, and coarse sand) is indicated by width of the section. Fine intra-unit lines illustrate sedimentary structure (planar and trough cross-bedding and horizontal lamination). Numbers 1–6 on the right correspond to unit numbers used in text. The black marks in units 1, 2, 4, and 5 represent mudballs in their relative volumetric proportions.