See: https://gsa.confex.com/gsa/2015SC/webprogram/Paper254211.html
Unfortunately, she has not uploaded her poster and it is not possible to see the tracks. Further, the abstract does not give the rock type, age of the rocks or the exact location. I am curious to see the results of the promised further investigations. It will be an exciting development if her tracks are confirmed as Climactichnites.
Interestingly, Lydia Roundtree is not the first to report Climactichnites from Texas. When I researched Cambrian rocks in central Texas I was taken to various publications describing the rocks from the Llano region of Texas. A quick reading of a few of the publications disclosed that in 1977 Virgil E. Barnes and W. Charles Bell reported, when describing the Cambrian Hickory Sandstone Member of the Riley Formation, that “Climactichnites(?) trails 4 inches wide are exposed in the bed of the Treadgill Creek (between 237 and 239 feet in line of section); such trails have not been seen elsewhere in the Llano region.”
[Virgil E. Barnes and W. Charles Bell, 1977, The Moore Hollow Group of Central Texas, Report of Investigations No. 88, Bureau of Economic Geology, The University of Texas at Austin, at page 77]
In addition, I believe that there are other references to Climactichnites from Texas in this and earlier reports. At pages 123 and 124 of the 1977 publication Barnes and Bell refer to “Climactonites” in combination with Cruziana from the Hickory Sandstone Member. I believe that they are misspelling Climactichnites as Climactonites. In two earlier publications by the same authors, when describing the same rocks, they also refer to Climactonites. See:
“These fossils occur above sandstone which is barren except for lebenspuren, such as Cruziana, Climactonites, and various other forms.”
W. Charles Bell and Virgil E. Barnes, 1972
Cambrian History, Llano Region, in Virgil E. Barnes, W. Charles Bell, S.E. Clabaugh, P.E. Cloud, Jr., R. V. McGehee, P.U. Rodda and Keith Young, Geology of the Llano Region and Austin Area, Field Excursion, Guidebook Number 13, Bureau of Economic Geology, The University of Texas at Austin, at page 24
“These fossils occur above sandstone which is barren except for Lebenspuren, such as Cruziana, Climactonites, and various other forms.”
W. Charles Bell and Virgil E. Barnes, 1962
Cambrian History, Llano Region, in Geology of the Gulf Coast and Central Texas, and Guidebook of Excursions, published by the Houston Geological Society for the 1962 Annual Meeting of the Geological Society of America, Edited by E. H. Rainwater and R. P. Zingula, at page 79
archives.datapages.com/data/hgssp/data/013/013001/pdfs/79.pdf
By far the best reference to the environment of the Hickory Sandstone, and one that confirms that Bell and Barnes were identifying Climactichnites, is a Masters thesis submitted to the University of Texas at Austin in 1975 by Frank Gary Cornish entitled “Tidally influenced deposits of the Hickory Sandstone, Cambrian, Central Texas”. He places the trackway Climactichnites in context with other trace fossils and in an environment that sounds much like that of the Nepean Formation of the Potsdam Group. Part of his abstract is as follows:
“ The six lithofacies of the Hickory Sandstone were deposited as nonbarred tidally-influenced or estuarine-related equivalents to deposits of Holocene environments. Outer estuarine tidal channel-shoal deposits display abundant channel fills of large-scale foresets, parallel bedded sandstone, and minor siltstone. Trilobite trackways (Cruziana) and resting traces (Rusophycus) occur in these deposits, associated with U-shape burrows (Diplocraterion and Corophioides). Deposits of open coast sandy tidal flats display upward-fining character, medium-to large-scale festoon crossbedding, abundant small-scale ripple bedforms of all types, and mudcracks. These deposits include the U-shape burrows, Corophiodes, and the trackway, Climactichnites. Deposits of inner estuarine tidal channels and tidal flats display upward-fining character, wavy-lenticular bedding, bimodal paleocurrent patterns, and the resting trace, Pelecypodichnus. All of these deposits prograded as a unit until sea level rise shut off sediment supply. Progradation of tidal channel and shoal sediments was renewed. These deposits are festoon crossbedded hematitic sandstone with wavy-lenticular bedding and abundant fossil debris. Storm energy funneled through tidal channels deposited crossbedded sandstone onto the nearshore inlet-influenced shelf. Final Hickory deposits and initial Cap Mountain deposits were storm-dominated, burrowed and laminated calcitic shelf sands.
Frank G. Cornish’s thesis can be downloaded from a link at: http://repositories.lib.utexas.edu/handle/2152/20401
A photograph of Climactichnites, a specimen found in Gillespie County, appears at page 43 as Plate II D of his thesis. It looks very much like Climactichnites to me.
Mr. Cornish mentions at page 9 of his thesis that “The trace fossils Cruziana and Climactichnites were first recognized by Bell and Barnes (1961).” This is a reference to the following paper:
Bell, W.C. and Barnes, V.E., (1961), Cambrian of central Texas: Internat. Geol. Cong., 20th, Mexico, 1956, El Sistema Cambrica, su paleogeographic y el problema de su base, Tomo III, p. 484-503. (I have not yet found that paper.)
I view the identification of Climactichnites from Cambrian rocks of Texas as an exciting find, as Climactichnites has wider range than I had expected and is not just confined to eastern North America .
Christopher Brett
Perth, Ontario
Update: July 23, 2015
I located Frank Cornish in Corpus Christi, Texas where he is the principal of Imagine Resources, LLC, a company that specializes in generating South Texas oil and gas prospects. Frank has generously given me permission to reproduce his photo of the trace fossil Climactichnites on my blog. His photo is reproduced below.
It certainly looks like the surface trace Climactichnites wilsoni Logan 1860– a trackway consisting of lateral ridges between which are undulating transverse bars and furrows.
In the text of his thesis Frank Cornish provides this description for the photo: Portion of the Epichnial trail, Climactichnites, from middle rippled unit of burrowed sandstone facies, section GI-CR, Gillespie County, scale: bar=5 cm.
Unfortunately, he no longer has the ichnofossils from his thesis. However, he does have the original negatives for the photographs appearing in his thesis.
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Added July 30, 2015:
Frank Cornish mentioned that the trace fossil Climactichnites wilsoni was found in the Cambrian Hickory Sandstone of Texas in an article published in Palaios in 1986, where he commented:
“The upper, burrowed unit is usually intensely bioturbated and has a massive if mottled appearance resulting from an extremely high density of Diplocraterion habichi burrows. Other trade fossils in this facies are Climactichnites wilsoni and Planolites monatus. No body fossils are present. The trace fossils are dominated by Diplocraterion, .... The vertical sequence of sedimentary structures, sedimentary textures, and biogenic structures demonstrates that this lithofacies accumulated on moderate-energy intertidal sand flats and intertidal sand bars...””
Frank G. Cornish, 1986,
The Trace-Fossil Diplocraterion: Evidence of Animal-Sediment Interactions in Cambrian Tidal Deposits, Palaios, Vol. 1, No. 5 (Oct., 1986), pp. 478-491 at page 481
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Those with a new found interest in the Hickory Sandstone should look at the following field trip guide:
www.geology.sfasu.edu/TASGuidebook2013.pdf
R. LaRell Nielson and Chris A. Barker, 2013
Geology of the Western Llano Uplift, Fredericksburg to Mason, Texas
Texas Academy of Science, 2013, Field Trip, 36 pages.
Stop 2 covers “Exposures of the Cambrian Hickory Sandstone are seen along Crab Apple Creek... The Hickory Sandstone at this location contains excellent sedimentary structures such as mudcracks, a wide variety of ripple marks and trough cross bedding.” Crab Apple Creek is in Gillespie County, and this stop could be at the outcrops that appear as photographs in Plate II in Frank Cornish’s thesis and are the “middle rippled unit of burrowed sandstone” where he found Climactichnites.
Figure 07 in the field trip guide is a photograph with the caption “ Exposures of the Hickory Sandstone along Crab Apple Creek contain well developed trough cross-bedding, ripple marks and mudcracks deposited during the Cambrian System in a beach environment.”
Figure 08 in the field trip guide shows “Ripple Marks in Hickory Sandstone along Crab Apple Creek” in Gillespie County and looks like the outcrop that appears as the photograph in Plate IIG in Frank Cornish’s thesis, which he identified as “slightly sinuous bifurcating current ripples from the middle rippled unit of burrowed sandstone facies, Section G1-CR, Gillespie County."
Figure 09 in the field trip guide shows “Mudcracks in Hickory Sandstone along Crab Apple Creek south east of Enchanted Rock Natural Area.” and looks like the outcrop that appears as the photograph in Plate IIC in Frank Cornish’s thesis, which he identified as“Mudcracks form middle rippled unit of burrowed sandstone facies, section GI-CR, Gillespie County.”
Not surprisingly, the Dresbachian (late Cambrian) age attributed to the Hickory Sandstone of Texas overlaps the Furongian (late Cambrian) age attributed to the rocks of Ontario, Quebec, New York, Missouri and Wisconsin where Climactichnites has been reported. (What I find truly interesting is that in the late 1800's Charles Doolittle Walcott identified the sandstones of the Llano area of Texas as Upper Cambrian and called them Potsdam sandstone as he had sandstones in New York, Missouri and Wisconsin.)
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