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Sedimentary structures typical in the Dresser Formation, Pilbara, Western Australia. (A) Wave ripple marks on a bed surface tilted about 30° toward the observer. Scale: 10 cm. (B) Ripple cross stratification in vertical section of a rock bed. Note dark laminae, of which examples are magnified in Fig. 5. (C) Tidalites forming a vertical stack of layers. Scale: 0.5 cm. (D) Oncoids in thin section. Scale: 0.25 mm.
