Content uploaded by Leonard Brand
Author content
All content in this area was uploaded by Leonard Brand on Jan 30, 2018
Content may be subject to copyright.
A preview of the PDF is not available
Field and laboratory studies on the Coconino Sandstone (Permian) vertebrate footprints and their paleoecological implications
Abstract and Figures
The fossil footprints in the Coconino Sandstone have long been considered to be evidence for eolian deposition. I conducted field study of the fossil footprints in Hermit Basin, the Grand Canyon, and laboratory studies of modern amphibian and reptile footprints on dry sand, damp sand, wet sand, and underwater sand. Five species of salamanders all spent the majority of their locomotion time walking on the bottom, under water, rather than swimming. The experimental animals produced footprints under all test conditions, both up and down the 25° slopes of the laboratory “dunes”. Toe marks and other details were present in over 80% of the fossil tracks, underwater tracks, and wet sand tracks, but less than 12% of the dry sand and damp sand tracks had any toe marks. Dry sand uphill tracks were usually just depressions, with no details. Wet sand tracks were quite different from the fossil tracks in certain features. The fossil tracks were most similar to the underwater tracks. These data suggest that the Coconino Sandstone fossil tracks should not be used as evidence for eolian deposition of dry sand.
Figures - uploaded by Leonard Brand
Author content
All figure content in this area was uploaded by Leonard Brand
Content may be subject to copyright.
... It was first described by Gilmore (1927Gilmore ( , 1928 and later revised by several studies (e.g., Baird 1952, Haubold 1971Haubold et al. 1995aHaubold et al. , 1995bVoigt 2005;Francischini et al. 2019;Marchetti et al. 2019b). Further finds from the Coconino Sandstone of the Grand Canyon were described by Brand (1979), Hunt and Santucci (2001), Francischini et al. (2019) and Marchetti et al. (2019b), including either specimens in the field and specimens stored in the GRCA, Smithsonian and Yale collections. Some historic photos of in situ specimens are also stored in the GRCA collection (Figure 9-2). ...
... All the material from the Hermit Trail came from the lower half of the Coconino Sandstone (Gilmore 1926(Gilmore , 1927 (Figure 9-14). Subsequent studies of Coconino Sandstone footprints have focused on ichnotaxonomy, locomotion and paleoecology, with the study of new material from the Mogollon Rim area and also through comparisons with modern equivalents (e.g., McKee 1944McKee , 1947Baird 1952;Brand 1979;Brand and Tang 1991;Lockley 1992;Loope 1992;McKeever and Haubold 1996;Haubold 2000;Lucas 2006, 2007;Citton et al. 2012;Francischini et al. 2019;Marchetti et al. 2019b). The material from Ash Fork in the Mogollon Rim area comes from the middle part of the Coconino Sandstone, showing a similar stratigraphic distribution compared to the GRCA tracks (e.g., Hunt and Lucas 2005a). ...
For more than a century, the Paleozoic units of the Grand Canyon National Park (GRCA) and nearby areas have yielded a remarkable collection of terrestrial vertebrate trace fossils, which are studied by the discipline named vertebrate ichnology. These traces were registered in the sediment, rapidly covered but not eroded by other sediment and later fossilized in the process of rock diagenesis. Unlike bones, they were not transported before their burial and preservation. Moreover, they can occur in units completely devoid of vertebrate skeletal remains. This is the case for some of the Paleozoic units of the GRCA, in which the only source of information on the extinct fauna is provided by vertebrate tracks. The GRCA vertebrate ichnofauna iss composed of relatively small tracks of quadrupedal tetrapods, including eureptiles, parareptiles, synapsids and non-amniotes that lived in desert, fluvial and marginal marine paleoenvironments. In the GRCA, the late Carboniferous Manachka and Wescogame formations include the oldest evidence of vertebrate tracks from eolian paleoenvironments. The ichnoassociation of the early Permian Coconino and Hermit formations is dominated by reptile tracks, in agreement with a low-latitude and facies-crossing reptile radiation that started during the Artinskian. The Coconino Formation is crucial for the understanding of vertebrate locomotion and paleoecology in desert paleoenvironments and includes the first known evidence of non-amniotes in these settings. For all these reasons, the vertebrate trace fossil collection from the GRCA is of noteworthy scientific importance and needs to be protected and further investigated.
... Interpretations of the Permian Coconino Sandstone began primarily with the work of McKee (1934McKee ( , 1945 and Reiche (1938), followed later by subsequent work (Fisher, 1961;Sorauf, 1962;Lundy, 1973;Elcock, 1993;Sumner, 1999;Maithel et al., 2019Maithel et al., , 2021. Recent studies focused on (1) stratigraphic relationships (Blakey and Middleton, 1983;Blakey, 1990); (2) paleoenvironmental implications of tetrapod trackways (Brand, 1979;Brand and Tang, 1991;Lockley et al., 1992 [see 'Reply,' p. 668-670]; Lockley and Hunt, 1995 [see p. 40-56]; Brand and Kramer, 1996;Millhouse, 2009;Citton et al., 2012); (3) sedimentary properties (Maithel et al., 2019(Maithel et al., , 2021; or (4) soft-sediment deformation (Brand and Maithel, 2021). Most authors consider the Permian Coconino Sandstone to be an eolian dune deposit (McKee, 1934;Reiche, 1938;Baars, 1961;McKee, 1974;McKee and Bigarella, 1979;Loope, 1984;Blakey, 1988;Middleton et al., 2003). ...
Polygonal “cracks” are common in the Coconino Sandstone in Arizona. They have been called desiccation cracks, but several features indicate they are not desiccation cracks. They were never open cracks, but are merely linear depressions, linked to form polygons. They occur only on bounding surfaces, containing almost no clay, and the cracks extend 10 to 15 cm above and below the bounding surfaces. The polygonal patterns continue down from one sandstone lamina to another, for several centimeters. They are persistently continuous across all surfaces within their 20–30 cm vertical range, from the bottomset beds, onto the bounding surface, and continuing into individual cross-beds below the bounding surface. The cracks occur at the Grand Canyon, and are especially numerous and visible in flagstone quarries in the Seligman and Ash Fork area. They occur on some bounding surfaces but not on others, and in some quarries but not in others. The polygonal cracks have been mentioned in passing, but this is the first reported research on these cracks in the Coconino Sandstone. Polygonal cracks have been reported in the Navajo, Page, and Entrada Sandstones, but there are significant differences between these and the Coconino Sandstone cracks, which may indicate differences in their origin.
... McKee (1934) was the first to propose and develop an eolian depositional model for the Coconino SS. Subsequent studies followed this work (e.g., Reiche 1938;McKee 1945;Fisher 1961;Sorauf 1962;Lundy 1973;Elcock 1993;Sumner 1999;Maithel et al., 2021), focused on stratigraphic relationships Blakey 1990), tetrapod trackways (Brand 1979(Brand , 1992Brand and Tang 1991;Lockley and Hunt 1995;Brand and Kramer 1996;Millhouse 2009;Citton et al., 2012), or sedimentary properties (Maithel et al., 2019(Maithel et al., , 2021. Similarly to McKee (1934), most authors interpret the formation as an eolian dune deposit (Reiche 1938;Baars 1961;Mckee 1974;Blakey and Middleton 1983;Loope 1984;Blakey 1988;Middleton et al., 2003). ...
The Permian Coconino Sandstone of northern Arizona contains numerous small-scale, soft-sediment deformation structures (SSDSs). These novel structures may be indicators of paleoenvironment or sedimentary processes. These SSD are generally shallow and occur on the surfaces of cross-beds, in contrast to convoluted bedding up to tens of meters thick commonly observed in some other eolian sandstones. These differences in structures imply differences in the processes that formed the Coconino Sandstone, or differences in the underlying depositional conditions. These SSDSs occur in outcrops at the Grand Canyon, and farther south in quarries near the towns of Seligman and Ash Fork. Size, orientation, structure, sedimentary context, clay content, and porosity of the structures are described. The SSDSs occur as small folds and ridges on the paleo lee side of otherwise undisturbed cross-beds. Some are associated with small rotated sandstone blocks within the cross-beds. The structures are exposed on bedding plane surfaces and in cross-section on vertical quarry walls. A few SSDSs up to a meter thick also occur in the Coconino Sandstone, but the others are only up to a few cm thick, 2–10 cm wide, and 20 cm to 10 m long. Evidence is presented that liquidization (as fluidization or liquefaction) may have been involved in producing these features, implying a high water content in scattered locations at time of deformation, but this process also requires some stressor to trigger the deformation. Seismic events may provide a triggering mechanism. The Coconino Sandstone SSDSs represent unusual or previously overlooked small-scale features related to individual foreset surfaces.
... In typical eolian facies of Botucatu Formation, tracks were interpreted as "cut undertracks", which are formed with the autopodia crossing through the superficial layer of dry sand and reaching damper layers below. Several deposits of ancient dunes were previously interpreted as subaqueous or at least moist paleoenvironments based on preservation of fossil tracks in it, as the Jurassic Navajo Sandstone and the Permian Coconino Sandstone (e.g., Brand, 1979;Brand and Tang, 1991;Mckeever, 1991;Rainforth, 2001), both in the USA. Abruptly starting and stopping trackways were interpreted by Brand and Tang (1991) as the result of the animal alternately walking on and swimming over the substrate, but it also could be explained if the animal moved between distinct grain flow lobes (Loope, 2006). ...
This work aimed to investigate the ichnofossiliferous sites in Nioaque and surrounding region, Mato Grosso do Sul state, Brazil, analyzing their paleontological, stratigraphic and paleoenvironmental context, because dinosaur tracks were found in an area previously mapped as Permo–Carboniferous age. Some sedimentary facies previously assigned to the glacial Aquidauana Formation were herein reinterpreted as part of the basal section of the Botucatu Formation (Late Jurassic/Early Cretaceous) and include floodplain and residual channel deposits, possibly representing the lower half of this formation's sequence in the studied area. The ichnofossils that have been found include both isolated tracks of Theropoda and Ornithopoda, a trackway of Eubrontes isp., a vertebrate burrow and invertebrate traces (Palaeophycus) possibly related to the Entradichnus ichnofacies. Sedimentological interpretation suggests the existence of a river system just before the deposition of the typical Botucatu eolian facies in this region. This is the first documented record of fluvial deposits transitionally to the traditional eolian Botucatu Formation. Noteworthy, the dinosaur tracks have played a key role for the interpretation of these rocks as Botucatu Formation and for better understanding the whole system due to the impossible Paleozoic age (dinosaur tracks).
... The formation and preservation of tetrapod tracks and trackways are closely related to the trackmaker (identity, size and gait), sedimentary substrate (grain size, moisture content and dip), sedimentary environments and fluid dynamics (water and wind) (Brand, 1979;McKeever, 1991;Gatesy et al., 1999;Manning, 2004;Jackson et al., 2009Jackson et al., , 2010Mancuso et al., 2016;Marchetti et al., 2019). In general, track preservation requires: (1) impression into a slightly moist substrate; (2) formation of surface cohesion and scour resistance by the means of subaerial exposure or cementation; (3) rapid burial ensured by high sedimentary rate, without enough hydrodynamic force to rework the track-bearing sediment. ...
... The formation and preservation of tetrapod tracks and trackways are closely related to the trackmaker (identity, size and gait), sedimentary substrate (grain size, moisture content and dip), sedimentary environments and fluid dynamics (water and wind) (Brand, 1979;McKeever, 1991;Gatesy et al., 1999;Manning, 2004;Jackson et al., 2009Jackson et al., , 2010Mancuso et al., 2016;Marchetti et al., 2019). In general, track preservation requires: (1) impression into a slightly moist substrate; (2) formation of surface cohesion and scour resistance by the means of subaerial exposure or cementation; (3) rapid burial ensured by high sedimentary rate, without enough hydrodynamic force to rework the track-bearing sediment. ...
Ancient desert, characterized by low biotic diversity as well as low preservation potential, has long been assumed as devoid of biotic activity. However, recent works from Mesozoic trace fossils preserved in the eolianites in North America, South America and East Asia indicate that the ancient desert can also have diverse inhabitants. This paper presents a diversified preserved dinosaur track assemblage from the Jurassic-Cretaceous transition eolian dune deposits in western Shandong Province, China. Based on the ichnological analysis, tracks are assigned to ichnogenus Anomoepus, Eubrontes-like and Ornithopodichnus-like forms, representing the oldest and second example of the Chelichnus ichnofacies reported from China as well as Asia. Sedimentological analysis of the tracksites indicates that tracks occurred in linear dunes under arid climatic conditions. Well-preserved tracks with detailed anatomical information are more likely to be preserved in moist sands, contrary to the dry cohesionless sands. Anomoepus and Ornithopodichnus-like tracks cooccurring with northwestward winds were made during summer wet season, while Eubrontes-like track was present during winter dry season characterized by strong northeastward wind, implying different habits between ornithopod and theropod dinosaurs. The preserved Jurassic-Cretaceous transition dinosaur tracks in eolian dune deposits not only expand the spatial-temporal distribution of dinosaur fauna in North China, but also greatly improve our understanding of the adaptive capacity of dinosaurs in severe living conditions, such as the desert environment.
... Although aquatic animals that engage in underwater pedestrianism may do so while completely submerged (cf. Zug 1971;Brand 1979;Martinez 1996;Martinez, Full, and Koehl 1998;Coughlin and Fish 2009;Grigg and Kirshner 2015;Farlow, Robinson, Turner, et al. 2018a, b), the likely pneumaticity of their bodies makes it unlikely that sauropods could have done the same (Henderson 2004). This in turn sets an upper limit to how deep the water through which hypothetical punting sauropods moved could have been: probably no more than a few to several metres (Figs. ...
Three parallel, manus-only sauropod trackways from the Coffee Hollow A-Male tracksite (Glen Rose Formation, Kendall County, Texas) were studied separately by researchers from the Heritage Museum of the Texas Hill Country and the Houston Museum of Natural Sciences. Footprint and trackway measurements generally show good agreement between the two groups’ data sets. Footprints appear to be shallowly impressed true tracks rather than undertracks. One of the Coffee Hollow trackways shows marked asymmetry in the lengths of paces that begin with the left as opposed to the right forefoot, and two of the Coffee Hollow trackways are unusually broad. The Coffee Hollow trackways differ enough from the manus portions of other Glen Rose Formation sauropod trackways to suggest that they were made by a different kind of sauropod. Greater differential pressure exerted on the substrate by the forefeet than the hindfeet probably explains the Coffee Hollow trackways, like other manus-only sauropod trackways, but the possibility that they indicate unusual locomotion cannot at present be ruled out.
Mainstream scientists, including Woodward, Buckland, Prestwich, Suess, and Ryan and Pitman, have proposed a variety of theories to explain the biblical deluge. The extent of the flood in these theories has decreased as empirical knowledge of global geology has increased. In contrast, contemporary flood geology attempts to explain most of the geologic record in terms of a single, year-long, global catastrophe. Flood geology exists in the context of an alternate scientific universe with its own institutions, organizations, journals, and meetings. The views of Leonard Brand, Steven Austin, and Walt Brown, representative of flood geology, are discussed.
Lower Permian strata of the Boskovice Basin in the Czech Republic have yielded hundreds of largely complete seymouriamorph individuals, some of which are exceptionally preserved and have noticeable soft tissues, such as external gills and eye structures. The vast majority of these finds are referable to Discosauriscus austriacus, and almost exclusively represent larvae and juveniles tied to aquatic environments. Only one of the specimens discovered to date has been interpreted as an early adult, although late juvenile and early sub-adult stages have been proposed for it as well. Regardless, no other seymouriamorph adults have been reported from the Boskovice Basin so far. Here we present the first comprehensive assessment of seymouriamorph tracks and a trackway from the Asselian (lowermost Permian) of the Boskovice Basin. The morphology of the tracks is congruent with that of the ichnotaxon Amphisauropus and indicates an attribution to Discosauriscidae or that they belong to as yet unrecognized large seymouriamorphs. All tracks were made by individuals much larger than the largest discosauriscid known from bodily preserved material and are interpreted as those of adults tied to terrestrial environments, thus apparently documenting a habitat shift that occurred relatively late in the ontogenetic development of these seymouriamorphs. Furthermore, the largest track is preserved in extraordinary detail and includes soft part impressions such as digital, palmar and plantar flexion creases, making the specimen one of the best preserved seymouriamorph tracks described to date. Finally, one of the tracks originates from the lowermost Asselian and is therefore among the oldest known records of seymouriamorphs worldwide.
The new ichnospecies Paleohelcura araraquarensis isp. nov. is described from the Upper Jurassic-Lower Cretaceous Botucatu Formation of Brazil. This formation records a gigantic eolian sand sea ( erg ), formed under an arid climate in the south-central part of Gondwana. This trackway is composed of two track rows, whose internal width is less than one-quarter of the external width, with alternating to staggered series, consisting of three elliptical tracks that can vary from slightly elongated to tapered or circular. The trackways were found in yellowish/reddish sandstone in a quarry in the Araraquara municipality, São Paulo State. Comparisons with neoichnological studies and morphological inferences indicate that the producer of Paleohelcura araraquarensis isp. nov. was most likely a pterygote insect, and so could have fulfilled one of the ecological roles that different species of this group are capable of performing in dune deserts. The producer could have had a herbivorous or carnivorous diet or been part of the fauna of omnivores, being able to adopt herbivorous, carnivorous, and saprophagous diets when necessary. In modern dune deserts, some species of pterygote insects are detritivores (like Tenebrionidae), relying on organic matter that accumulated among the sand grains of the dunes during dry periods with no plant growth. The presence of additional burrows suggests that the Botucatu paleodesert would have had a detritivorous fauna like this. Based on the interpretation of the ichnofossil producers, it was possible to reconstruct the food web of this paleodesert. All the omnivorous and herbivorous invertebrates and the herbivorous ornithopod dinosaurs made up the primary consumers. These animals were, in turn, the food source for bigger carnivorous or omnivorous animals unable to feed on detritus, like arachnids, possible predatory insects, mammaliaforms, and theropod dinosaurs. The highest trophic level was occupied by larger theropod dinosaurs and mammaliaforms, which, because of their size, could prey upon a wide range of animals. The producer of Paleohelcura araraquarensis isp. nov. could have been a primary consumer if it were an omnivorous detritivore or a herbivore, or a secondary consumer if it were produced by a predatory insect or an omnivore relying on animal biomass. The description of this new trackway expands the knowledge on the faunal composition of the Botucatu paleodesert and provides insights into the ecological relationships in ancient deserts. The presence of these arthropod trackways in Mesozoic eolian deposits helps to trace a continuity between Paleozoic and post-Paleozoic desert ichnofaunas, further reinforcing a single Octopodichnus—Entradichnus Ichnofacies for eolian deposits.