Friday 4 June 2021

If a tree falls in a forest and no one is around to hear it fall, does it make a sound?

 Below I summarize a few obscure writings on the Potsdam sandstone.

A 1979 Master’s Thesis by John Cass on the Beekmantown Group in the Ottawa Basin


In 1979 John Cass authored  a Master’s thesis at the University of Ottawa entitled ‘Paleoenvironmental interpretation of the Beekmantown Group within the Ottawa Basin”.   This thesis covered the  Potsdam Group as Cass included the Potsdam within the Beekmantown Group.   

Cass  noted that Fisher (1977) had included the Keeseville formation within the Beekmantown, and commented (page 20) that “Without conclusive evidence of a major disconformity at or near the assumed Cambro-Ordovician boundary or within the Potsdam formation within the Ottawa basin, the entire transitional sequence from sandstone resting noncomformably on the Precambrian basement to carbonate underlying the Chazy Group, has been termed the Beekmantown Group for the purpose of this report.”    More recently, Dr. Bruce Sanford’s (2007) doctoral thesis and Dr. David Lowe’s (2016) doctoral thesis reported on a major systemwide unconformity within the Potsdam Group that is found in Ontario, Quebec and New York.  See also Sanford and Arnott (2010), Lowe et al. (2017, 2018).

Interestingly, Cass rejected Alice E. Wilson’s renaming of the Potsdam as the Nepean Formation, and divided the Potsdam into the Basal Member, Ausable Member and the Keeseville member (following Fischer, 1968).   He considered the Keeseville member in Ontario to be equivalent to Clark’s Cairnside formation in Quebec and to most of Alice E. Wilson’s Nepean formation in Ontario.

Cass also rejected Wilson’s renaming the Theresa formation as the March formation and rejected Wilson’s renaming of the Beauharnois formation as the Oxford formation.    He had a unique view of what we now call the  Theresa , breaking it down into the Theresa and Buck Bridge Formation, with the Buck Bridge formation consisting of a lower Heuvelton member and an upper March member.   While this is a unique interpretation for Canada, he was following Chapman’s (1915, p. 289) breakdown of transition beds in Upper New York into the Theresa, Heuevelton and Bucks Bridge.  

He provides a number of measured sections, including figures 6-8 and 6-9 for the Phillipsville outcrop, which he places in the Heuvelton member of the Theresa.  Some have mapped  it as Nepean; others, as March/Theresa.  (I have one friend who is a geologist to whom I commented “If you had three geologists look at that outcrop, you would get four opinions.”  My friend replied “Chris, if you had three geologists, you would get eight opinions.” He retired a few years later.)  Keith (1948) identified it as Potsdam formation. Wynne-Edwards’s (1967) map 1182A, where the Paleozoic Geology was by Morley Wilson  and G. M. Brownell in 1927 - 1929, shows it as Nepean Formation.  Williams and Wolf (1984, Map P. 2723) mapped at least the top of the outcrop as March.   Dr. Sanford (2007) mapped it as Potsdam.  Dr. Al Donaldson  and Chris Finlay (2008) identified it as Potsdam in a field trip guide. Williams (1991, OGS, OFR 5770, page 226) provides a measured section for the outcrop (His Section S WE-1: roadcut, Philipsville UTM 409500E, 4943350N) reporting 3.55 meters of March Formation at the top, underlain by 3.1 meters of Nepean Formation.   Professor Arnott (2012), in a field trip guide, comments that the escarpment is “Probably all within the Theresa/March” but adds the qualification “Or is it?” About four years ago I recall asking Dave Lowe what he thought and he replied Theresa.   I thought  at least the base was Nepean Formation.

The information in John Cass’s  Master’s thesis was never published and as far as I can determine has never been referred to other than by Williams (1991, page 22) who lists it among various studies on the Potsdam and Beekmantown Group and by Globensky (1986, page 71)  who rejected Cass’s terminology.    Globensky  (1986, page 71)  commented  “[ Google Translation from French:]  It is the same with Cass (1979) who rejects all the terminology used in Ontario, to adopt in part the American terms and to propose new ones; however, it retains the Beauharnois Formation. For him, the Beekmantown Group includes all the units between the Precambrian base and the Chazy Group. We are not inclined to accept these changes. It seems to us that the proposals of Giles (1976) and Cass (1979) only increase the profusion of names in the stratigraphic sequence of the St. Lawrence Lowlands. We prefer to stick to the definition of Wilson (1946); however, we use the equivalent names in Quebec, as defined by Clark (1966) and modified by Globensky (1982a). Thus, the Beekmantown Group includes only two formations: Theresa and Beauharnois.

A 1985 Master’s Thesis by Lee E. McRae on the basal Potsdam Sandstone in New York State, southwestern Quebec, and southeastern Ontario


In  1985 Lee McRae authored  a Master’s thesis at Dartmouth College entitled ‘Sedimentology and paleomagnetics of the basal Potsdam Sandstone in the Adirondack border region, New York State, southwestern Quebec, and southeastern Ontario’ .  

Lee McRae concentrated on the nonmarine facies within the basal Potsdam formation of the Adirondack border areas of northern New York, south eastern Ontario along the St. Lawrence (Brockville, Gananoque, Kingston) , and southwestern Quebec (Covey Hill, St. Cristostome, Ile Perrot, NW Montreal), only briefly mentioning the overlying shallow marine units. She provides  observations  and  analysis of sedimentary structures,  paleocurrent directions, and petrographic studies .   She identified six distinct lithofacies:  

Lithofacies 1 - Massive matrix-supported conglomerate (e.g. at Allens Falls, N.Y. at Mosherville, N.Y.  at Whittaker Falls, N.Y.), interpreted to represent an alluvial fan that developed as clastic debris was rapidly shed off an adjacent Prccambrian high debris flows.

Lithofacies 2 - Stratified framework-supported conglomerate (e.g. , a thick conglomerate sequence on Wellesley Island, N.Y. and the lower part of the sequence at Browns Bay, Ontario) with cut and fill structures common, interpreted to represent proximal gravelly braided-stream deposits.

Lithofacies 3 -Framework supported conglomerate-arkose (e.g., the upper sections at Wellesley Island, N.Y., and sequences at Oak Point, Dekalb Junction, and south of Canton), charactcrized  by finer framework supported conglomerate, shallow scour surfaces, and lenticular pods of conglomerate, with clast imbrication well developed, and trough and planar cross stratified sandstones,  interpreted to represent intermediate to distal gravelly braided-stream deposits (the downstream, distal equivalent of Lithofacies 2).

Lithofacies  4 - Pebble conglomerate-arkose fining-upward sequences (e.g., the upper sequences at Nicholveille, the upper section at Whittaker Falls, numerous exposures in the Champlain Valley) , interpreted to represent  sandy braided-stream deposits.

Lithofacies  5 - large-scale cross-bedded quartz arenite (e.g. at Alexandria Bay and at Hannawa Falls), interpreted as deposited in a subaerial, eolian setting.    For Lithofacies 5 she reported some cross-stratification features not consistent with eolian deposition (trough cross bedding; reversely oriented foresets), and suggested an alternative origin  of deposition in a high energy, tidally influenced, near shore estuarine or deltaic environment.   Others including  Sanford (2007) and Lowe (2016) identify the rocks at Hannawa Falls as an eolian deposit.  Husinec  (2020b) and  Hagadorn,  Collette and Belt (2010) emphasize the eolian dunes at Hannawa Falls, but characterize the Hannawa Falls  outcrop as a suite of interfingering eolian dune and aquatic deposits.  Professor  Husinec’s (2020b) YouTube video “Potsdam Sandstone Eolian Deposits" shows the deposits at Hannawa Falls.

Lithofacies  6 - Basal Conglomerate Thick Bedded Quartz Arenite (e.g., a section at Wellesly Island, and an exposure in the Hudson/Mowhawk Valley), characterized by a thin layer of well rounded conglomerate, overlain by a succession of poorly sorted sandstone, in turn overlain by massive bedded quartz arenite,  interpreted as the initial deposits associated with a shallow marine transgression.
            
Lee McRae mentions the seventh Lithofacies, the overlying shallow marine units, but did not cover this facies in her thesis.

Lee McRae makes a point that I have been thinking about for a few years, namely that the type locality for the Potsdam at Hannawa Falls is not typical for the formation as a whole.   (The underlying deposits of the Potsdam  Group are largely aluvial fans or braided stream deposits, while the overlying beds that are largely shallow marine deposits.)   Lee McRae mentions that the locality at Hannawa Falls “typifies the variability in lithologic types which are included under the name “Potdam”, and it is an interesting, perhaps ironic fact that the type exposure is not only imperfectly exposed, but is rather atypical of the formation as a whole.”  Fisher (1977) had commented that while the sandstone at  Hannawa Falls was the type, it was atypical, and renamed it his Ausable Formation: “Ausable Sandstone (Alling, H. L. 1919, p. 144)  Red and pink-white mottled lower Potsdam; probably the red, highly crossbedded sandstones at Hannawa Falls, the type (but atypical!).”   Lowe (2016, page 185) noted that“the well-known large-scale cross-stratified red bed exposures  along the Raquette River south of the town of Potsdam ... were first described by Emmons (1838) and deemed the type section of the “Potsdam Sandstone”. Here, it is deemed the type section of the Hannawa Falls Formation.”
      
Lee McRae noted that “ The desertlike environment of the Precambrian surface allowed for rapid transport and deposition of relatively unweathered sediments and the subsequent construction of a braided alluvial plain system. Field relations ...  suggest that terrestrial Potsdam deposition in the Early and Middle Cambrian largely preceded the marine transgression that deposited the thick, shallow marine units typifying most of the Potsdam sequence.”
         
The last half of Lee McRae’s thesis is devoted to the paleomagnetics of the basal Potsdam Sandstone.
            
Lee McRae’s  Master’s thesis was not published though the part on the sedimentology of the basal Potsdam Sandstone was summarized in an abstract authored by McRae and  Johnson (1986) delivered at the AAPG Annual Convention.  Her work on the Potsdam facies was briefly  cited by Hagadorn and Belt (2008), is relied on in seven places in Hagadorn, Collette and  Belt (2010) and is relied on in Husinec and Donaldson’s ( 2014, pages 2-3) field trip guide.  

Another part of Lee McRae’s thesis dealing with paleomagnetics  was included in a Geology Society of America abstract authored by  McRae,  Johnson,  and Johnson (1986).  It is briefly mentioned by Bruce Selleck (2008, page 145) who commented  “ McRae, et al (1986) used paleomagnetic techniques to determine a poorly-constrained early Paleozoic depositional age for the Ausable member and other basal Potsdam Sandstone units in the northern New York State outcrop belt. However, the intense post-depositional alteration of the Potsdam Sandstone suggests that the primary depositional paleomagnetic signal was not preserved, and that the remanence measured is likely a diagenetic artifact.” (Interestingly, David Lowe (2016) proposed similar early Cambrian depositional ages for the Ausable member.)   McRae,  Johnson,  and Johnson’s  (1986) abstract has been  cited by others:   Landing (2012, p. 465) cites it as support for the proposition that the lower Potsdam might be as old as the Proterozoic;   Hagadorn and  Belt (2008, page 425) cite this paper as support for the proposition that “a significant fraction of the lower strata of the [Potsdam]  could be Early–Middle Cambrian”.

All of Hagadorn and  Belt (2008) , Hagadorn, Collette and  Belt (2010) and Husinec and Donaldson  (2014) reference Lee McRae’s thesis on the Potsdam as a doctoral thesis. While it reads like a doctoral thesis, it was a Masters.  Her doctoral thesis was completed in 1989 and  dealt with chronostratigraphic variability in fluvial sequences as revealed by paleomagnetic isochrons in Miocene Strata.

Engelder And Sbar’s 1976 paper on strain orientation in the Potsdam Sandstone

        
Engelder and Sbar (1976) made strain measurements at five sites in Potsdam sandstone. That part of their paper has been cited in papers on strain measurements in other formations.   What I find interesting is their breakdown of the formations in the Potsdam and the assignment of the oldest part to the late Proterozoic.  They commented (Page 3015) “The Potsdam sandstone consists of three members in ascending order: (1) the Nicholville, (2) the Ausable, and (3) the Keeseville. ... The Nicholville member is a coarse to medium-grained arkose which is believed to be late Proterozoic (Hadrynian) (D. W. Fisher, personal communication, 1975).  The Keeseville is a Late Cambrian medium grained quartz sandstone representing a high-energy intertidal zone (Fisher, 1968).   ... [the Nicholville member] is believed to have filled a later Proterozoic (Hadrynian) fault graben.  The orientaton of the fault grabens filled by the eicholville member is thought to be parallel to the northeast lineaments, which have been mapped by Isachsen (1976) in the Proterozoic (Helikian) rocks of the Adirondack Mountains ( D. W. Fisher, personal communication, 1975).” ...  [Page 3016:] “In contrast to the Nicholville, the Keeseville member was deposited during a marine transgression upon a stable continental shelf.”

Fisher’s  1956 paper on the  Cambrian system of New York State


While this paper was referred to in the 20 years after publication, it has been largely overlooked in the past few decades.  It is worth noting that Fisher rejected the names Ausable and Keeseville:

[page 329:] “Rejected names, by virtue of synonymy and/or lack of usage
   Ausable (Alling, 1919) - lack of usage, probably not a valid unit
   Keeseville (Emmons, 1841)  – not a valid unit”

[page 333: ] “ KEESEVILLE - Although Emmons (1841, pp 130-131) treated the Keeseville sandstone as a variety of the Potsdam sandstone, the name later was revived for the upper predominantly white portion of the Potsdam and the name Potsdam was restricted to the lower , largely red , portion ( Chadwick , 1920 ) . The type locality is at Keeseville , Clinton County , near famous Ausable Chasm .  As reddish and white sandstone interfinger , the advisibility of using two names is questioned .”
    
The Lexicon of Geologic Names of the United States for 1936-1960, followed  Fisher:
Keeseville Sandstone
Upper Cambrian(?): Northern New York.
Original reference: E. Emmons, 1841, New York Geol. Survey 5th Rept., p.    130, 131.
D. W. Fisher, 1956, Internat. Geol. Cong., 20th, Mexico, Cambrian Symposium, pt. 2, p. 333. Although Emmons (1841) treated Keeseville sandstone as variety of Potsdam sandstone, name was later revived for upper predominantly white part of the Potsdam, and name Potsdam was restricted to lower, largely red, part (Chadwick, 1920, New York State Mus. Bull. 217–218). Because reddish and white sandstone interfinger, advisability  of using two names is questioned. Not considered valid name.
Ausable Sandstone
Upper Cambrian: Eastern New York.
Original reference: H. I. Alling, 1919, New York State Mus. Bull. 207, 208, p. 113-145.
D. W. Fisher, 1956, Internat. Geol. Cong., 20th, Mexico, Cambrian Symposium, pt. 2, p. 329. Name was briefly mentioned by Alling (1919), and never since used, for basal Potsdam underlying the white Potsdam or "Keeseville" sandstone. Probably not valid unit."
    
Fisher (1968) resurrected the names Ausable and Keeseville, when he subdivided the Potsdam into three units:
[Page 15:] “Three lithologic types ( facies ) of Potsdam  
1 Basal  member Allen Falls of Kryning (1943); Nichoville of Postel, Nelson and Wiesnet (1959) maroon or dusky red    Hematitic, feldspathic , micaceous, quartzose sandstone having high accessory mineral content; some maroon shale interbeds.
2 Ausable Member - highly crosslaminated orange pink to pale red very coarse to medium grained arkose (feldspathic sandstone) with quartzose green shale seams and conglomeratic lenses.
3 Keeseville Member pinkish gray to very pale orange regular bedded, clay deficient , quartz sandstone, only slightly feldspathic”

Dennison ‘s  1982 Summary of Previous Work on the Potsdam


In 1982 John Dennison wrote a report entitled ‘Uranium favorability of nonmarine and marginal-marine strata of late Precambrian and Paleozoic age in Ohio, Pennsylvania, New Jersey, and New York .’    A  chapter (pages 79-89) in the report summarizes previous work on the Potsdam sandstone from Emmons (1838, 1842)  to Selleck (1975).    I don’t believe that this has ever been cited  as a reference for the Potsdam.  It is worth reading.  

Wilmarth’s (1938) Lexicon of Geologic Names of the United States also provides a good summary of the use of the terms Potsdam Sandstone, Keeseville sandstone and Ausable sandstone.

Regards,
Christopher  Brett
Ottawa, Ontario

References and Suggested Reading

Arnott,  R.W.C., 2012
 Three day field trip to  Potsdam Group outcrops, Unpublished.  4 pages. 30 stops.

Blumberg, E., Chiarenzelli, J.R., Husinec, A., and Rygel, M., 2008,
 Insight from cores in the Potsdam Group, northern New York: Geological Society of America, Abstracts with Programs, Northeastern Section, v. 40, p. 82.
https://gsa.confex.com/gsa/2008NE/webprogram/Paper134416.html
Northeastern Section - 43rd Annual Meeting (27-29 March 2008)

Cass, John I. , 1979
Paleoenvironmental interpretation of the Beekmantown Group within the Ottawa Basin. Thesis, Master of Science, University of Ottawa.  189 pages plus 90 page Appendix. https://ruor.uottawa.ca/bitstream/10393/8394/1/MK43988.PDF
http://hdl.handle.net/10393/8394

Dennison, John M., 1982
Potsdam Sandstone, chapter (pages 79-89) in Uranium favorability of nonmarine and marginal-marine strata of late Precambrian and Paleozoic age in Ohio, Pennsylvania, New Jersey, and New York .     https://digital.library.unt.edu/ark:/67531/metadc1202671/

Donaldson, Allan & Chris Findlay, 2008
Geotour  of Frontenac Arch Biosphere Reserve. Sunday, October 5, 2008 Friends of Canadian Geoheritage


Engelder, J. T. And Sbar, Marc L., 1976
Evidence for uniform strain orientation in the potsdam sandstone, Northern New York, from in situ measurements. Journal of Geophysical Research , vol 81, No. 17, 3013-3017

Fisher, D. W., 1956
The Cambrian system of New York State; Cambrian Symposium, 20th International Geological Congress, Mexico City, p. 321-351.  El sistema Cámbrico, su paleogeografía y el problema de su base : symposium
    
Fisher, D. W.,  1968
Geology of the Plattsburg and Rouses Point New York-Vermont Quadrangles: N.Y. St. Mus. Sci. Serv., Map and Chart Ser., Not 10, 51 p
    
Fisher, D.W., 1977
Correlation of the Hadrynian, Cambrian and Ordovician rocks in New York State: New York State Museum, Map and Chart Series no. 25, 75 p

Globensky, Yvon, 1986
Géologie de la région de Saint-Chrysostome et de Lachine (sud). Gouvernement du Québec , Ministère de l'Energie et des Ressources, Direction générale de l'Exploration géologique et minérale  MM 84-02
http://gq.mines.gouv.qc.ca/documents/EXAMINE/MM8402/MM8402.pdf
    
Hagadorn, James W.  and Edward S. Belt, 2008
Stranded in Upstate New York: Cambrian Scyphomedusae from the Potsdam Sandstone PALAIOS Vol. 23, No. 7/8 (Jul. - Aug., 2008), pp. 424-441  

Hagadorn, J.W.,  J.H. Collette, E.S. Belt, 2010
 Eolian-aquatic deposits and faunas of the middle Cambrian Potsdam Group. Palaios 26 (5), 314-334   a suite of interfingering eolian dune and aquatic deposits

Husinec, Antun, 2020a
 "Potsdam Sandstone" on YouTube
https://youtu.be/LhvHYVSsG6I    Time: 13:37    22 Aug 2020
This video was filmed for the Sedimentology Virtual Lab, St. Lawrence University during the COVID-19 pandemic.  

Husinec, Antun, 2020b
 “Potsdam Sandstone Eolian Deposits" on YouTube
 https://youtu.be/fN7hOY9l7y4    Time:    7:47.   Sept 4,  2020
This video was filmed as a part of the Sedimentology Virtual Lab series during the COVID-19 pandemic.   

Husinec,  Antun and J Allan Donaldson,  2014
Lower Paleozoic Sedimentary Succession of the St. Lawrence River Valley, New York and Ontario, in: Geology of the Northwestern Adirondacks and St. Lawrence River Valley (pp.1-28)  86th NEGSA Annual Meeting Field Guidebook, Chapter: A-1. Publisher: New York State Geological Association

Keroher, Grace C. and others, 1966
Lexicon of Geologic Names of the United States for 1936-1960
Bulletin 1200. USGS    https://doi.org/10.3133/b1200 

Keith, M. L., 1948
Sandstone as a Source of Silica Sands in Southeastern Ontario, with map No. 1946-9, part V in
Fifty-fifth Annual Report of the Ontario Department of Mines ,  being Vol. LV, 1946, 36 pages plus five detailed maps 


Landing, Ed, 2012
The Great American Carbonate Bank in Eastern Laurentia: Its Births, Deaths, and linkage to Paleooceanic Oxygenation (Early Cambrian-Late Ordovician), pages 451-492 in The Great American Carbonate Bank: The Geology and Economic Resources of the Cambrian– Ordovician Sauk Megasequence of Laurentia.  Edited by   James Derby, Richard Fritz, Susan Longacre, William Morgan, Charles Sternbach.  Memoir 78, American Association of Petroleum Geologists        

Li L. And  Ji S., 2020
A new interpretation for formation of orthogonal joints in quartz sandstone.   Journal of Rock Mechanics and Geotechnical Engineering https://doi.org/10.1016/j.jrmge.2020.08.003
“an anatomic investigation on the orthogonal joints in the Potsdam sandstone of Cambrian age at Ausable Chasm (New York State, USA) and Beauharnois (Quebec, Canada.”

Lowe, David G., 2016
 Sedimentology, Stratigraphic Evolution a and Provenance of the Cambrian – Lower Ordovician Potsdam Group in the Ottawa Embayment and Quebec Basin.  Doctoral Thesis submitted to the University of Ottawa, 435 pages
http://hdl.handle.net/10393/35303   http://dx.doi.org/10.20381/ruor-261
    
Lowe, David G., Arnott, R.W.C., Chiarenzelli, J.R., and Rainbird, R.H., 2018,
Early Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Geological Society of America Bulletin, v. 130, no. 7/8, p. 1377–1396, https:// doi .org /10.1130 /B31749 .1 .

Lowe, David G.;  Arnott, R.W.C.; Nowlan, G.; McCracken, A.D., 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
            
McRae, Lee E., 1985
Sedimentology and paleomagnetics of the basal Potsdam Sandstone in the Adirondack border region, New York State, southwestern Quebec, and southeastern Ontario: Unpublished M.Sc. thesis, Dartmouth College, Hanover, New Hampshire, 178 p.
        
McRae, Lee Ellen, 1989  
Chronostratigraphic variability in fluvial sequences as revealed by paleomagnetic isochrons: examples in Miocene strata from a central Andean intermontane basin (Salla, Bolivia) and the northwest Himalayan foreland (lower Siwalik Group, Chinji Formation, Pakistan. (xvi, 252.  Doctoral Thesis. Dartmouth College

McRae, Lee E.  And G. D. Johnson, 1986
Sedimentology of Basal Potsdam Sandstone in Adirondack Border Region, New York, Southeastern Ontario, and Southwestern Quebec.  AAPG Search and Discovery Article #91043 1986 AAPG Annual Convention, Atlanta, Georgia, June 15-18, 1986.
http://www.searchanddiscovery.com/abstracts/html/1986/annual/abstracts/0619d.htm

McRae, L., Johnson, G., and Johnson, N., 1986,
 Temporal reevaluation of late Hadrynian non-marine facies in the Adirondack border region, New York State, southeastern Ontario and southwestern  Quebec; Abstracts with Programs, Geology Society of America, 18, 1, p. 54

Sanford, B. V., 2007
Stratigraphic and structural framework of the Potsdam Group in eastern Ontario, western Quebec and northern New York. Doctoral Thesis submitted to the University of Ottawa
http://hdl.handle.net/10393/29694
http://dx.doi.org/10.20381/ruor-13101

Sanford, B.V. and R.W.C. Arnott, 2010
Stratigraphic and structural framework of the Potsdam Group in eastern Ontario, western Quebec and northern New York State, GSC Bulletin 597

Schmerber, G. And  Morizet, M. 1971
Etude sédimentologique: I - Les grès de Potsdam; II - Les dépôts de Kamouraska; Ministère des
Richesses naturelles, Québec, unpublished manuscript (In French)
https://gq.mines.gouv.qc.ca/documents/EXAMINE/SOQ02125/SOQ02125.pdf

Selleck, Bruce  2008
Stratigraphy, sedimentology and diagenesis of the Potsdam Formation, Southern Lake Champlain Valley, New York .   Field Trip Guidebook for the 80th Annual Meeting of the  New York State Geological Association.  
http://www.nysga-online.net/wp-content/uploads/2018/09/2008_bookmarked.pdf
 
Williams,  D.A.  1991.  
Paleozoic  Geology  of  the  Ottawa-St.  Lawrence  Lowland,  Southern  Ontario;  Ontario  Geological  Survey,  Open  File  Report  5770,  292p.        

Williams, D. A. and Wolf,  R.R., 1984,
Paleozoic geology, Westport area, Southern Ontario. Ontario Geological Survey, Map P. 2723.

Wilmarth, M. Grace, 1938
Lexicon of Geologic Names of the United States. USGS Bulletin 896, Part , A-L. 

Wynne-Edwards, H R., 1967
Geology Westport, Ontario. Geological Survey of Canada, "A" Series Map 1182A.  Paleozoic Geology by M. E. Wilson, 1928, 1929; G. M. Brownell, 1927, 1928.  Precambrian geology by H. R.   Wynne-Edwards,   1957. 1958  doi:10.4095/108032

Tuesday 1 June 2021

What's New in Potsdam Sandstone?

 Not much.   Li and Ji (2020) investigated the orthogonal joints in the Potsdam sandstone  at Ausable Chasm (New York State) and Beauharnois (Quebec) and Professor Antun Husinec (2020 a, b) at St. Lawrence University has published two Youtube videos on the Potsdam sandstone.     Below I have provided links to that  recent paper  and to the  two Youtube videos on the Potsdam sandstone published in 2020 by Antun Husinec.  While the outcrops in the videos are referenced and figured in numerous field trip guides (e.g., Husinec and Donaldson,  2014;  Lowe,  2014;  Selleck, Arnott, and Sanford, 2010)  and peer reviewed articles,  the videos  are  impressive.

Both videos were  filmed for the Sedimentology Virtual Lab, St. Lawrence University during the COVID-19 pandemic, by  Antun Husinec, Professor of Geology, St. Lawrence University, New York State.   The first video, entitled ‘"Potsdam Sandstone" shows four outcrops:  the first outcrop is a mile and half from Alexandria Bay with great shots of a nonconformity;  the second outcrop [7:30] is  at Goose Bay a mile and half northeast of previous outcrop; the third outcrop [9:38] is at Schermerhorn  landing   and shows  an unconformity within the Potsdam; the fourth outcrop [11:19] is at Chippewa Bay with U shaped burrows, disconformably overlain by  theTheresa formation.   The second video entitled “Potsdam Sandstone Eolian Deposits" has great shots of eolian dunes in the sandstone.

Interestingly,  Professor George Dix of Carleton University’s  Earth Sciences Department has also prepared a series of Virtual Sedimentary Geology Field Trips [see: https://newsroom.carleton.ca/story/virtual-sedimentary-geology-field-trips/ ]. The only one that I can find on the web is a short [2:56 ; 7 Oct 2020] video on the Theresa Formation.   In that video he mentions that there is one on the Keeseville, but I cannot locate it.
 
Li and Ji (2020) observed  that at both sites the  orthogonal joints in the Potsdam sandstone “are organized essentially in grid-lock pattern, rather than ladder-pattern .  Mutual abutting/cutting relationships (e.g. both sets of joints abut each other) indicate that the orthogonal joints are geologically coeval extension fractures.  Each set of orthogonal joints displays a uniform strike, and is straight and continuous over several meters. ...  Furthermore, these joints are opening-mode fractures and display no detectable shear displacement along them.  No joints contain detectable mineral fill indicating that brittle fracturing occurred at shallow depths where temperature was so low that the solubility of quartz or calcite was too low to form veins along the joints...”  [citations omitted].  They concluded that the “sandstone beds stretched in the direction not only parallel but also perpendicular to the maximum tensile stress (s3) direction in the flat-lying layers, forming closely-spaced fracture set J1 and widely-spaced fracture set J2. ... [and that the  vertical orthogonal joints resulted]   “from the auxetic effects of quartz-rich sandstone in the absence of local or regional stress rotation.”

Below I've listed papers from 2016 to 2019 that I've mentioned in footnotes to earlier blog posts.


Christopher  Brett
Ottawa, Ontario

References and Suggested Reading

Brink R., Mehrtens C., Maguire H., 2019
Sedimentology and petrography of a lower Cambrian transgressive sequence: Altona Formation (Potsdam Group) in northeastern New York.  Bulletin of Geosciences, 94, 369-388
http://www.geology.cz/bulletin/contents/art1728
 
Dashtgard, S. E., Vaucher, R., Yang, B., & Dalrymple, R. W. , 2021
Hutchison Medallist 1. Wave-Dominated to Tide-Dominated Coastal Systems: A Unifying Model for Tidal Shorefaces and Refinement of the Coastal- Environments Classification Scheme. Geoscience Canada, 48(1), 5–22. https://doi.org/10.12789/geocanj.2021.48.171
 [Free download]

Dix, George, 2020
Theresa Formation  (Marine Shoreface).  A YouTube video [2:56 minutes ; 7 Oct 2020]  
https://youtu.be/EJz12HnOEg0

Engelder, J. T. And Sbar, Marc L., 1976
Evidence for uniform strain orientation in the potsdam sandstone, Northern New York, from in situ measurements.  Journal of Geophysical Research , vol 81, No. 17, 3013-3017

Husinec, Antun, 2020a
 "Potsdam Sandstone" on YouTube
https://youtu.be/LhvHYVSsG6I    Time: 13:37 minutes.    22 Aug 2020
This video was filmed for the Sedimentology Virtual Lab, St. Lawrence University during the COVID-19 pandemic.  

Husinec, Antun, 2020b
 “Potsdam Sandstone Eolian Deposits" on YouTube
 https://youtu.be/fN7hOY9l7y4    Time:    7:47 minutes.   Sept 4,  2020
This video was filmed as a part of the Sedimentology Virtual Lab series during the COVID-19 pandemic.  

Husinec,  Antun and J. Allan Donaldson,  2014
Lower Paleozoic Sedimentary Succession of the St. Lawrence River Valley, New York and Ontario, in : Geology of the Northwestern Adirondacks and St. Lawrence River Valley (pp.1-28)  86th NEGSA Annual Meeting Field Guidebook, Chapter: A-1. Publisher: New York State Geological Association

Landing, E., Salad Hersi, O.,  Amati, L., Westrop, S.R., Franzi, D.A., 2019
Early Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Comment. GSA Bulletin; March/April 2019; v. 131; no. 3/4; p. 695–698; https://doi.org/10.1130/B35104.1; published online 25 January 2019.

Li L. And,  Ji S., 2020
A new interpretation for formation of orthogonal joints in quartz sandstone.   Journal of Rock Mechanics and Geotechnical Engineering
https://doi.org/10.1016/j.jrmge.2020.08.003
“an anatomic investigation on the orthogonal joints in the Potsdam sandstone of Cambrian age at Ausable Chasm (New York State, USA) and Beauharnois (Quebec, Canada.”


Lowe, David G.,  2014.
Stratigraphy and Terrestrial to Shallow Marine Environments of the Potsdam Group in the Southwestern Ottawa Embayment. In Geology of the Northwestern Adirondacks and St. Lawrence River Valley, New York State Geological Association 86th annual meeting guidebook, pp. 183–203

Lowe, David G., 2016
Lower Ordovician Potsdam Group in the Ottawa Embayment and Provenance of the Cambrian – Lower. Ordovician Potsdam Group in the Ottawa. Embayment and Quebec Basin. David G. Lowe. Doctoral Thesis submitted to the University of Ottawa
http://hdl.handle.net/10393/35303
http://dx.doi.org/10.20381/ruor-261

Lowe, David G, and R.W.C. Arnott, 2016
 Composition and Architecture of Braided and Sheetflood-Dominated Ephemeral Fluvial Strata In the Cambrian–Ordovician Potsdam Group: A Case Example of the Morphodynamics of Early Phanerozoic Fluvial Systems and Climate Change.  Journal of Sedimentary Research, v. 86, i. 6, p. 587-612, Published in June 2016, doi:10.2110/jsr.2016.39  

Lowe, D.G., Arnott, R.W.C., Chiarenzelli, J.R., and Rainbird, R.H., 2018,
Early Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Geological Society of America Bulletin, v. 130, no. 7/8, p. 1377–1396, https:// doi .org /10.1130 /B31749 .1 .

Lowe, D.G., Arnott, R.W.C., Chiarenzelli, J.R., and Rainbird, R.H., 2019,
Early Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Reply. Geological Society of America Bulletin, March/April 2019, v. 131, no. 3/4, pages 699-703; published online January 25, 2019.  https://pubs.geoscienceworld.org/gsa/gsabulletin/article/131/3-4/699/568492/Early-Paleozoic-rifting-and-reactivation-of-a

Lowe, David G.;  Arnott, R.W.C.;  Nowlan, G.; McCracken, A.D., 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. ,  James W. Hagadorn, Robert H. Dott Jr, 2019
Cambrian wave-dominated tidal-flat deposits, central Wisconsin, USA
Sedimentology, Volume 66, Issue5, August 2019, Pages 1643-1672
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McMahon,William J.,  A. G. Liu, B. H. Tindal, and M. G. Kleinhans, 2020
Ediacaran life close to land: coastal and shoreface habitats of the Ediacaran macrobiota, the central Flinders Ranges, South Australia .  Journal of Sedimentary Research, 2020, v. 90, 1463–1499     https://doi.org/10.2110/jsr.2020.029
 

[Attributed to]  Selleck, B., Arnott,  R.W.C. and Sanford, B. V., 2010
 Potsdam Formation Field Excursion, July 22-25, 2010, Thousand Island Region and St. Lawrence Lowlands.  Colgate University.