Below are photographs of loose specimens and bedrock at Tackaberry’s quarry located on highway 7 about two miles north of Perth, in Lanark County, Ontario. The photographs show fossil ripple marks, primarily symmetric ripples, that originally formed under water. (However, when I was taking photographs I was mainly looking for ripples with curvilinear cracks in the ripple troughs or shrinkage cracks on the ripples. I was not looking for asymmetric ripples.)
The first photo shows ripples in bedrock at the quarry. Sam_27
The remainder of the photographs are of loose specimens resulting from blasting at the quarry.
An interesting point about photographing loose specimens is that it is as likely that I photographed a bed top as a bed sole.
The next two photos show a bed sole and a bed top of symmetric ripples, though probably not parts that match. Sam_62 and Sam_63
The previous photo also shows the curvilinear cracks that formed in many ripple troughs in specimens found at the quarry.
The next photos show a crust on the ripples, that might result from a microbial mat: Sam_133 (a bed sole) and 135 (a bed top).
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The next photo show a number of superimposed thin beds with symmetrical ripples on the top beds and symmetrical ripples on the lower bed, with the two sets of ripples going in different directions. Sam_151
The next photos, Sam_153 and 152, are close ups of the above photo, the second showing polygonal shrinkage cracks in the ripples.
Geologic Map
Below is an extract from Ontario Geological Survey Map P. 2724 entitled Paleozoic Geology Perth Area, issued 1984, geology by D. A. Williams and R. R. Wolf, 1982, on which I’ve plotted the location of Tackaberry’s quarry and the location of the Glen Quarry where Climactichnites wilsoni was found by Dr. James Wilson of Perth, and named by Sir William Logan after Dr. Wilson. The map puts Tackaberrry’s quarry within the March Formation, which is thought to be Lower Ordovician in age, and places the Glen Quarry within the Nepean Formation of the Potsdam Group .
The upper bar scale on the map is in tenths of a mile and 1 mile. The lower bar scale is in tenths of a kilometre and 1 kilometre. The major faults are shown on the map, with the arrow indicating the downthrown side. The legend shows that the letters PC on the map indicate undifferentiated Precambrian igneous and metamorphic rocks, that the number 2 on the map indicates Nepean Formation sandstones of the Potsdam Group, and that the number 3 on the map indicates March Formation interbedded quartz sandstone, sandy dolostone and dolostone.
On the map I’ve also shown the approximate location of the Hands quarry that was described in 1931 by Dr. Morley Wilson of the Geological Survey of Canada. While the Hands quarry is only two miles south of Tackaberry’s current quarry on Highway 7, and both are mapped as March Formation, the rocks at the two quarries are quite different. The map shows that a fault separates two blocks that have been mapped as March formation, with Tackaberry’s quarry falling on the western block and Hands quarry falling on the southeastern block. The rocks at Hands quarry would be considered typical March Formation (or, more accurately, typical of parts of the March Formation). I mentioned in my September 24, 2012 blog posting that the rocks at Tackaberry’s quarry differ from other areas that have been mapped as March Formation. I still hold that view. The rocks at Tackaberry’s quarry are not typical March Formation, and there might only be a veneer of March Formation.
In my September 24, 2012 blog posting I suggested ‘Drummond sequence’ for the block where Tackaberry’s quarry is located and suggested that the rocks appear to be much older than typical March Formation rocks. I also mentioned that Sir William Logan had reported that he had found Climactichnites and Protichnites at a quarry in Lot 6, Concession 3, Drummond Township, which would fall within the Drummond Sequence. However, my subsequent investigations (see my blog postings of January 31, 2013 , February 11, 2013 and May 6, 2013) showed that the Glen quarry is actually on Lot 3, Concession 3, Drummond Township, and falls in Cambrian Potsdam sandstone rather than within the Drummond sequence that has been mapped as Lower Ordovician March Formation. On the below map I plotted the Glen quarry on Lot 3, Concession 3, Drummond Township on property owned by the Glen family at the time Dr. James Wilson found the tracks that Logan named Climactichnites wilsoni, and where I found a small quarry.
Ripple Marks at the Hands Quarry, Lanark County, Ontario
Dr. Morley Wilson is, I believe, the only person to have written a paper devoted to Ripple marks near Perth, Lanark County. In a short paper published in 1931in the Canadian Field-Naturalist he described ripple marks in the March Formation (known in Dr, Morley Wilson’s time as the “Transition Beds”) and included photographs of the ripple marks. The ripple marks occurred in a quarry “on the farm of Mr. H. J. Hands, Lot 10, Concession II, Drummond Township, Lanark County”. Morley Wilson also mentions that “ The quarry lies about 3 miles northeast of Perth and 300 yards north of the second line of Drummond which forms a part of the original stage road from Perth to Ottawa, ...”. The second line of Drummond is more commonly called the Franktown Road and is shown on maps as County Road 10. Jim Hands and his son Trevor both own property on that lot and Concession, and Jim’s property would be familiar to many Lanark residents as Jim and Trevor are well known auctioneers, and Jim has held many an auction on his property.
Morley Wilson mentions that the ripples occur in thin beds on the Hands quarry floor “everywhere throughout the entire extent of the quarry which is over 200 feet long and 100 feet wide and throughout a range of about 14 inches. The total thickness of strata exposed in the quarry face is about 5 feet. This consists of thin bedded sandy dolomitic limestone, in which beds or zones of white limestone up to 1 inch thick are intercalated sparingly near the top but more abundant near the bottom.”
Morley Wilson also mentions that “The sandstone of ... the Transition Beds is ripple marked in many places, the ripples being for the most part of the unsymmetrical type. The greater part of the ripples trend northeast-southwest or east-west and the steeper side of the crests of the ripples are on their south-east or south sides indicating that the current by which they were formed came from the north-west or north.”
The March Formation
D. A. Williams (1991) of the Ontario Geological Survey states that “The March Formation consists of interbedded quartz sandstone, dolomitic quartz sandstone, sandy dolostone, and dolostone.... Shaly partings occur throughout the formation, and glauconitic partings are present in the dolostones and sandy dolostones. ... Quartz sandstones of the March Formation ... are thinly to thickly bedded, fine to coarse grained, and well sorted. The sandstones range in colour from white to light grey, brown, reddish brown, and green; and weather white to light grey and brown to reddish brown. Small brown-weathering spots are common, and are the result of diffusion into the surrounding pore spaces of iron derived from detrital pyrite, magnetite, or ilmenite grains. The quartz grains are subrounded to well rounded. ... Crossbedding, ripple marks, and burrows are common. The dolomitic quartz sandstones and sandy dolostones are light to medium brownish to bluish grey in colour, and weather brownish grey to buff to reddish brown. They are thinly to thickly bedded and contain finely to medium crystalline carbonate and well rounded, fine to coarse grained quartz sand. Some dolomitic sandstone beds are calcareous, and some sandy dolostone beds are calcitic.
...
The March Formation was deposited in a supratidal to subtidal environment. Supratidal to intertidal deposition and hypersalinity are implied by calcite-filled vugs (originally sulphate nodules) and algal lamination in the dolostones. Intertidal deposition is implied by bipolar crossbedded quartz sandstone containing discrete vertical burrows. Subtidal deposition is indicated by highly bioturbated dolomitic quartz sandstone (Bond and Greggs 1973, p.1147-1150). A similar environment was inferred for the Theresa Formation of adjacent New York State by Selleck (1984).”
Williams’ description would cover the rocks of the Hands’ quarry (sandy dolomitic limestone), but is not apt for the majority of rocks of Tackaberry’s quarry as cross-bedding is not common, the burrows are confined to the top beds, there are no calcite-filled vugs, and there is little dolostone in Tackaberry’s quarry. In addition, finding the Ediacaran holdfast Aspidella in the rocks tells against the rocks being Lower Ordovician March Formation.
References and Selected Bibliography
Below I’ve provided a few references to water ripples and wind ripples. If the reader is going to read one reference in addition to Morley Wilson’s paper, it should probably be Kindle (1917). That said, Evans (1942) makes the important point that “The size of wave-formed ripple marks depends on the depth of water and the size of the generating waves. With waves of a given size, the deeper the water the smaller the ripple marks; with a given depth of water, the smaller the waves, the smaller the size of the ripple marks.”
Christopher Brett
Ottawa, Ontario
Postscript (March 19th): It has always impressed me that Sir William Logan was able to identify both water ripple marks and wind ripple marks in the Potsdam sandstones at Beauharnois where he found Protichnites tracks, and that he concluded that the creature “which impressed the [Protichnites] tracks at Beauharnois must have been a littoral animal.” See: Logan (1860), where he named Climactichnites Wilsoni; and Logan (1863), The Geology of Canada. It is also worth noting that Logan (1863) provides various measured sections of Potsdam sandstone, including a section from Beauharnois in the vicinity of Henault’s field (1863, pages 105-106), where he describes the beds and indicates where ripple marks, wind marks, Protichnites tracks and Scolithus occur.
References and Selected Bibliography
Blondeaux, P., Foti, E. and G. Vittori, 2015
A theoretical model of asymmetric wave ripples. Philosophical Transactions: Mathematical, Physical and Engineering Sciences. Vol. 373, No. 2033, Theme issue: Advances in fluid mechanics for offshore engineering: a modelling perspective (28 January 2015), pp. 1-20
https://www.jstor.org/stable/24506135
Das, Siddhartha Sankar and Sengupta,Supriya , 1997
Height vs water depth for small sand ripples – An aid to palaeohydraulics, Current Science, Vol. 72, No. 9 (10 May 1997), p. 626
https://www.jstor.org/stable/24099669
Evans, O. F. 1941.
The classification of wave-formed ripple marks. Journal of Sedimentary Petrology, 11, 37.41.
https://doi.org/10.1306/D42690DF-2B26-11D7-8648000102C1865D
Evans, Oren Frank, 1942
The relation between the size of wave-formed ripple marks, depth of water, and the size of the generating waves . Journal of Sedimentary Research (1942) 12 (1): 31-35.
https://doi.org/10.1306/D4269139-2B26-11D7-8648000102C1865D
Hints, Linda, 2008
Ripple marks as indicators of Late Ordovician sedimentary environments in Northwest Estonia. Estonian Journal of Earth Sciences, Volume 57, 1, 11-22. doi: 10.3176/earth.2008.1.02
https://www.researchgate.net/publication/26503506
Jackson, D. W. T. and Cooper, J. A. G., 1999
Formation of Ephemeral Bedform Turrets in Coastal Foredunes , The Journal of Geology
Vol. 107, No. 5 (September 1999), pp. 633-639
https://www.jstor.org/stable/10.1086/314367
Johnson, Douglas W., 1916
Contributions to the Study of Ripple Marks , The Journal of Geology
The Journal of Geology, Vol. 24, No. 8 (Nov. - Dec., 1916), pp. 809-819 (11 pages)
https://www.jstor.org/stable/30061204
Kindle, E. M., 1917
Recent and Fossil Ripple-Marks, Geological Survey of Canada, Museum Bulletin 25, No. 1658, Geological Series, No. 34, 121 pages https://doi.org/10.4095/104987
https://archive.org/details/museumbulletin25geol
Kindle, E. M., 1923
Notes on Mud Crack and Ripple Mark in Recent Calcareous Sediments. The Journal of Geology, Vol. 31, No. 2 (Feb. - Mar., 1923), pp. 138-145
https://www.jstor.org/stable/30079396
Kindle, E. M. 1936
Notes on Shallow-Water Sand Structures
The Journal of Geology, Vol. 44, No. 7 (Oct. - Nov., 1936), pp. 861-869
https://www.jstor.org/stable/30056273
King, W. J. Harding, 1916
The Nature and Formation of Sand Ripples and Dunes, The Geographical Journal, Vol. 47, No. 3 (Mar., 1916), pp. 189-207
https://www.jstor.org/stable/1779300
Menard, Henry, W. 1950
Current-Ripple Profiles and Their Development , The Journal of Geology
Vol. 58, No. 2 (Mar., 1950), pp. 152-153
https://www.jstor.org/stable/30071109
Sarkar, Soumen, 1981
Ripple marks in intertidal Lower Bhander Sandstone (late Proterozoic), Central India: A morphological analysis - Sedimentary Geology, Volume 29, Issue 4, August 1981, Pages 241-282
https://www.sciencedirect.com/science/article/pii/0037073881900762
Seppälä, Matti and Krister Lindé, 1978
Wind Tunnel Studies of Ripple Formation
Geografiska Annaler. Series A, Physical Geography, Vol. 60, No. 1/2 (1978), pp. 29-42
https://www.jstor.org/stable/520963
Sharp, Robert P., 1963
Wind Ripples. The Journal of Geology Vol. 71, No. 5 (Sep., 1963), pp. 617-636
https://www.jstor.org/stable/30061128
Williams, D.A., 1991.
Paleozoic Geology of the Ottawa-St. Lawrence Lowland, Southern Ontario; Ontario Geological Survey, Open File Report 5770, 292p.
http://www.geologyontario.mndm.gov.on.ca/mndmfiles/pub/data/imaging/OFR5770//OFR5770.pDf
Wilson, Morley Evans, 1931
Ripple marks near Perth, Lanark County, Ontario: Canadian Field-Naturalist, vol. 45, no. 2, pp. 25-27, 3 figs., February 1931.
https://www.biodiversitylibrary.org/item/89041#page/41/mode/1up
Xiao, Qianlu, Li, Ruijie, Li, Chunhui and Xuwen Fang, 2018
Predicting Wave-induced Ripple Geometry and Bottom Friction Factor
Journal of Coastal Research, Special Issue 83: Advances in Sustainable Port and Ocean Engineering (Fall 2018), pp. 148-154
https://www.jstor.org/stable/26542947
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