Fig. 2. Stratigraphy of the Douglas Group (after Archer, Lanier et al., 1994). Two valley-fill sequences (Tonganoxie and Ireland) are illustrated.
This study focuses on a 9-m (30-ft)-thick succession of the Tonganoxie Sandstone Member exposed in the Buildex Quarry, southwest of the town of Ottawa in Franklin County, Kansas (NW sec. 23, T. 17 S., R. 19 E.). At Buildex Quarry, the Stranger Formation overlies the Weston Shale, and consists of the Ottawa coal and the Tonganoxie Sandstone Member. Exposures of the Tonganoxie Sandstone Member are present along the north, west, and south faces of the quarry. The north (fig. 3) and south walls are too steep to allow detailed observations; however, the west wall contains a bench along its expanse allowing full access to this outcrop face.
Fig. 3. General view of the north wall at Buildex Quarry. Note the disconformable contact between the laterally continuous Tonganoxie Sandstone Member and the underlying Weston Shale Member. The Ottawa coal occurs between these two units.
Trace fossils analyzed in this paper were collected from the lowest 5 m (16.5 ft) of the Tonganoxie Sandstone Member. The specimens described by Bandel (1967), also considered in this study, were recovered from the same locality. With respect to the stratigraphic position of these specimens, Bandel recorded that they "occur in a sequence, 1 m thick, of about 20 thin-bedded siltstone and claystone strata overlying the Ottawa coal" (Bandel, 1967, p. 2).
Kansas Geological Survey
Web version March 19, 1998