I suspect everyone who is interested in trace fossils from the Potsdam Group sandstones is familiar the specimens of Protichnites and Diplichnites that have been reported from eolian (wind blown) sandstones of the Sloan quarry that is south of Washburn Road, about 20 kilometers northeast of Kingston, Ontario. The trackways were made famous by the article ‘First steps on land: Arthropod trackways in Cambrian-Ordovician eolian sandstone, southeastern Ontario, Canada’ that was authored by R. MacNaughton, J. Cole, R. Dalrymple, S. Braddy, D. Briggs and T. Lukie, and published in 2002 in Geology, volume 30, pages 391–394. In that article Dr. MacNaughton and his co-authors reported on arthropod tracks found in the eolian (wind blown) sandstones. The tracks are important because they were made on eolian sandstones in an eolian dune field (rather than on tidal flats), possibly in a marginal-marine setting, and record one of the first creatures to walk on land. They reported three types of tracks: (1) a repeated series of 7 or 8 circular to tapered tracks with a medial impression; (2) trackways with no series structure , with a medial impression; (3) two parallel rows of tracks with no medial impression. Types (1) and (2) are Protichnites while type (3) is Diplichnites. They commented that the trackways were made by arthropods with at least eight pairs of walking legs, with at least some of the tracemakers possessing a telson (tail spine). They suggested euthycarcinoids as the creature that made the Protichnites tracks.
The eolian (wind blown) sandstones at the Sloan quarry where the Protichnites and Diplichnites tracks were found are now called the Hannawa Falls Formation of the Potsdam Group. Those rocks are now thought to be middle Cambrian in age (about 510 million years old) - See Lowe (2016) and Lowe et al. (2017).
The trackways found at the Sloan quarry have been featured in other articles. For example, Sandford and Arnott (2010, Figure 49, page 49) includes a photograph of a Protichnites trackway from the Hannawa Falls sandstones at the Sloan quarry on Washburn Road. In addition, Krapovickas, Mangano, Buatois, and Marsicano, (2016, Figure 2, b, c and d) include Dr. MacNaughton’s photographs of Protichnites and Diplichnites trackways from the Sloan quarry. Hagadorn, Collette, and Belt (2011) reported similar trackways from the eolian Middle Cambrian Potsdam Group sandstones of Upper New York State.
Yesterday, November 10th, I dropped in at Rideau Contracts’ Lansdowne Quarry at Ellisville, Ontario. (The forecast was for a sunny day with an unseasonable high of 23 degrees Celsius.) There are three operations at the quarry. First, Tackaberry has sublet part of the quarry and is busy crushing rock into gravel. Second, Rideau Contracts quarries rock at the quarry which it slabs, cuts and tumbles. Third, Rideau Contracts operates a cutting and trimming facility where it brings in rock (limestone, granite and sandstone) that is quarried elsewhere and cuts and trims it for resale.
When I dropped in at the quarry Wayne Jackson was good enough to tell me that this past winter he had quarried 50 cubic meters of sandstone from the quarry on Washburn Road and that he and his father had noticed tracks on a few of the blocks of sandstone. Wayne mentioned that his father was in possession of a slab showing the clearest track, but thought there might be tracks on another specimen. Below are two photographs of a Diplichnites trackway on a block of eolian sandstone from the Sloan quarry, that I took while at the Lansdowne Quarry at Ellisville, Ontario.
The trackway is about 4 inches (10 cm) wide. The ruler in the photographs is a meter stick.
Wayne said that he would try to save the trackway when the block is trimmed. I suggested donating it to the geological museum at Queen’s University.
Christopher Brett
Ottawa
References and Suggested Reading
Hagadorn, James W., Joseph H. Collette, and Edward S. Belt, 2011
Eolian-aquatic deposits and faunas of the Middle Cambrian Potsdam Group
Palaios 26(5):314-334 May 2011 DOI: 10.2307/25835633
Krapovickas, V., Mangano, M.G., Buatois, L. A. And Marsicano, C., 2016.
Integrated Ichnofacies models for deserts: recurrent patterns and megatrends. Earth-Science Reviews, 157, 61-85
Lowe, David G., 2016
Sedimentology, Stratigraphic Evolution and Provenance of the Cambrian – Lower Ordovician Potsdam Group in the Ottawa Embayment and Quebec Basin;
Doctoral Thesis, University of Ottawa,
http://www.ruor.uottawa.ca/handle/10393/35303
Lowe, David G. , R.W.C. Arnott, Godfrey S. Nowlan, A.D. McCracken, 2017
Lithostratigraphic and allostratigraphic framework of the Cambrian–Ordovician Potsdam Group and correlations across Early Paleozoic southern Laurentia
Canadian Journal of Earth Sciences, 2017, 54(5): 550-585, https://doi.org/10.1139/cjes-2016-0151
MacNaughton, Robert B; Jennifer M. Cole; Robert W. Dalrymple; Simon J. Braddy; Derek E.G. Briggs; Terrence D. Lukie, 2002
First steps on land: Arthropod trackways in Cambrian-Ordovician eolian sandstone, southeastern Ontario, Canada. Geology, volume 30, Issue 5, pages 391–394.
https://doi.org/10.1130/0091-7613(2002)030<0391:FSOLAT>2.0.CO;2
Mcnamara, K. J., 2014
Early Paleozoic colonisation of the land: evidence from the Tumblagooda Sandstone, Southern Carnarvon Basin, Western Australia. In: Journal of the Royal Society of Western Australia
Volume 97, Issue 1, Pages: 111--132 https://www.biodiversitylibrary.org/page/58073791#page/119/mode/1up
McNamara, K.J., and Trewin, N.H., 1993,
A euthycarcinoid arthropod from the Silurian of Western Australia: Palaeontology, v. 36, p. 319–335.
https://www.palass.org/sites/default/files/media/publications/palaeontology/volume_36/vol36_part2_pp319-335.pdf
Sanford, B. V. and Arnott, R. W. C., 2009
Stratigraphic and structural framework of the Potsdam Group in eastern Ontario, western Quebec, and northern New York State; by Sanford, B V; Arnott, R W C; Geological Survey of Canada, Bulletin no. 597, 2009, 1 sheet;,
https://doi.org/10.4095/247673
Wolf, R.R., and Dalrymple, R.W., 1985,
Sedimentology of the Cambro-Ordovician sandstones of eastern Ontario, in Milne, V.G., ed., Geoscience Research Grant Program, summary of research 1984–1985: Ontario Geological
Survey Miscellaneous Paper 127, p. 112–118.
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