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TABLE 1. Comparison of taphofacies recognized in the Morrison Formation, including A) a site example, lithology, paleontology, weathering of the bones (where available), transportability of the bones (where available), and B) the fauna represented (available in PDF only).

TABLE 2.Summary of taphofacies recognized in circum-lacustrine environments including 1) swampy environments with episodic fluvial influence, 2) fluvial environments which were periodically covered by lacustrine deposits (fluvio-deltaic), and 3) a swampy/lacustrine environment.

Taphofacies

Example

Sedimentology

Paleontology

Weathering

Transport Groups

Swampy environment with episodic fluvial influence Huelago-1 (Albderdi et al, 2001) Green and gray silts with charcoal intraclasts, cyanobacterial oncoids, root traces. Iron oxide preciptate horizons. Interbedded muddy sand-filled channel bodies with a basal mud pebble conglomeratic sand and silt and clay carbonate beds with incipient pedogenic features. Gastropods, fish, equilibrium between identified and unidentified bone remains, abundant isolated teeth, small animals most common, predator damage, algal crust, no articulated remains, some associated remains, trampling common, concentrations of bones, some orientation Advanced weathering stages 1-3 Appendages (2.5%), Teeth (28.87%), Group III (1.49%), Group II (7.13%), Group 1 (5.8%), Fragments (54.35%), Coprolites (0.64%)
Swampy / lacustrine environment Cullar de Baza-1 (Alberdi et al., 2001) Carbonates and marlstones interfingering with alluvial sediments Fish, reptiles, rodents, rabbits, carnivores, ungulates, some articulated remains Most are Stage 0, 12% in advanced stages Appendages (2.14%), Teeth (23.92%), Group III (5.71%), Gropu II (6.34%), Group I (4.76%), Fragments (56.44%), Coprolites (1.22%)
Delta plain Subenv. A (Mancuso and Marsicano, 2008) Medium- to coarse- grained sandstone interbedded with black mudstone and very fine grained sandstone. Sandstone beds are tabular to lenticular with basalt mudstone intraclasts. Logs, tetrapod footprints, invertebrate trace fossils, no bone orientation Most are Stage 0 Not directly reported, but skeletons were mostly articulated and showed no evidence of sorting
Deltaic front Huescar-1 (Alberdi et al., 2001) White calcareous silt beds devoid of organic matter and lamination. Detrital beds grade east into a 3 m thick bed which also contains bone remains. This bed is formed of stacked lens-like bodies of gravelly sands. Planar cross-stratification occurs occasionally . Fish, semi-aquatic birds and mammals, predominance of unidentified bone remains, abrasion and breakages common, rounding of bones, no carnivore evidence on bones (may have been abraded), densely concentrated and uniformally distributed, evident dip of the bone bed to the west, preferential orientation of bones Stages 2-3 (not including fragments) Appendages (0.23%), Teeth (19.76%), Group III (0.79%), Group II (2.54%), Group I (6.13%), Fragments (70.49%), Coprolites (0.07%)
Deltaic front Subenv. B (Mancuso and Marsicano, 2008) Upward caorsening sequence characterized by alternation of tabular-massive siltstone and claystone interbedded with parallel laminated, very fine grained sandstone. Sandstones with current-ripples to horizontal lamination and planar to trough cross-bedded in uppermost coarse grained material plant fragments, fish body fossils, tetrapod footprints, invertebrate trace fossils, no bone orientation, breaking common Stage 0-1 (not including fragments) Not directly reported, but skeletons were mostly articulated and only fish and trace fossils were reported, showed moderate evidence of sorting
Prodelta Subenv. C (Mancuso and Marsicano, 2008) Dark gray to black carbonaceous claystone Plant debris, conchostrans, bivalves, insects, scarse partially articulated fish remains, no bone orientation, breaking common Stage 0-1 (not including fragments) Not directly reported, but skeletons were partially articulated and only fish and trace fossils were reported, showed moderate evidence of sorting
Offshore lacustrine Subenv. D (Mancuso and Marsicano, 2008) Dark gray to black carbonaceous claystone plant debris, insects, conchostrans, fish, no bone orientation, breaking common Stage 0-1 (not including fragments) Not directly reported but skeletons were disarticulated and only fish fossils were reported, high evidence of sorting

TABLE 3. Voorhie’s groups for non-sauropod bones based on data from coyote skeletons (Voorhies, 1969) and Fluvial Transport Index Groups for sauropod bones based on elephant bones (Frison and Todd, 1986).

Group 1

Group 2

Group 3

Voorhies FTI Voorhies FTI Voorhies FTI
Sacrum Sacrum Scapula Scapula Mandible Mandible
Vertebrae Vertebrae (except Atlas) Humerus Humerus Skull Skull
Ribs   Tibia Tibia   Atlas
Sternum   Metapodials Metapodials   Pelvis
  Patella Femur     Radius-ulna
  Astragalus Pelvis     Femur
  Calcaneous Radius      
    Phalanges      
    Ulna      
      Ribs    

TABLE 4. Weathering and abrasion scale of bones.

0 No damage at all. Bone is in near perfect condition, smooth surface with no cracking or breaking.
0.5 Intermittent stage between 0 and 1.
1 Bone shows cracking, longitudinal and/or latitudinal congruent to structure.
1.5 Intermittent stage between 1 and 2.
2 Flaking on outer most layer, following and/or from cracks. Flakes are still attached to bones on one or more edges.
2.5 Heavier flaking, flakes easily removed from bone, or flakes fall off bone when the bone is moved.
3 Patches of rougher bone on surface, connecting patches In patches, and layers. External bone is missing. Patches of weathering are shallow.
3.5 Intermittent stage between 3 and 4.
4 First stage of advanced weathering. Large sections of flaking, pieces falling from the bone when touched or moved. Rough surface texture, rounding of cracked edges.
4.5 Intermittent stage between 4 and 5.
5 In Situ, the worst specimen to be examined. Virtually unrecognizable, splintered into pieces, breaks easily when moved. Perhaps undeterminable.

 

TABLE 5. Faunal list of organisms at the Aaron Scott Quarry.

 

Bivalvia Linnaeus, 1758                  
  Unionoida Rafinesque, 1820                
    Unionidae Rafinesque, 1820              
Reptilia Laurenti, 1768                  
  Testudines Batsch, 1788                
    Cryptodira Cope, 1868              
      Glyptopsidae Marsh, 1890            
        Glyptops Marsh, 1890          
          Glyptops cf. plicatulus        
    Sphenodontia Williston, 1925              
      Sphenodontidae Cope, 1869            
        Opisthias Marsh, 1890          
          Opisthias rarus Gilmore, 1905        
  Archosauria Cope, 1869                
    Crocodyliformes Benton and Clark, 1988              
      Goniopholididae Cope, 1875            
        Indet. cf. Eutretauranosuchus sp. Mook, 1967          
  Dinosauria Owen, 1842                
    Saurischia Seeley, 1888              
      Theropoda Marsh 1881            
        Carnosauria Heune, 1920          
          Allosauridae Marsh, 1879        
            Allosaurus Marsh, 1877      
              Allosaurus cf. fragilis Marsh, 1877    
        Coelurusauria Huene, 1914          
          Coeluridae Marsh, 1881        
            Coelurus sp. Marsh, 1879      
      Sauropoda Marsh, 1878            
        Diplodocidae Marsh, 1884          
          Barosaurus Marsh, 1890        
          Apatosaurus March, 1877        
        Camarasauridae Cope, 1877          
          Camarosaurus Cope, 1877        
    Ornithischia Seeley, 1888              
      Ornithopoda Marsh, 1881            
        Dryosauridae Milner & Norman, 1985          
          Dryosaurus sp. Marsh, 1894        
      Stegosauria Marsh, 1877            
        Stegosauridae Marsh, 1880          
          Stegosaurus sp. Marsh, 1877        
Mammalia Linnaeus, 1758                  
    Triconodonta Osborn, 1888              
                   

 

 

TABLE 6. Comparison of the Aaron Scott Quarry to the Huescar-1 locality, interpreted to be a fluvio-deltaic depositional setting. Red text indicates areas where the different examples match.

 

Aaron Scott Quarry

Huescar-1

Los Rastras Formation Subenvironment C

Figures

Sedimentology Basal siltstone with rip-up clasts; calcareous siltstone; beds dipping to the west; shale layer on top White calcareous silt beds, detrital beds dipping to the west Upward caorsening sequence characterized by alternation of tabular-massive siltstone and claystone interbedded with parallel laminated, very fine grained sandstone. Sandstones with current-ripples to horizontal lamination and planar to trough cross-bedded in uppermost coarse grained material Fig. 4
Orientation Slight preferential orientation Slight preferential orientation No bone orientation Fig. 8, 10
Taxonomy Abraded unidentified bones common, semi-aquatic animals, large herbivores common, carnivore teeth, disarticulated remains Abraded unidentified bones common, semi-aquatic animals, large herbivores common, disarticulated remains Abraded unidentified bones common, articulated fish remains, plant debris, conchostrans, bivalves, insects Table 3, Fig. 9
Distribution Bones are densely concentrated and uniformly distributed Bones are densely concentrated and uniformly distributed Bones are densely concentrated Fig. 4
Weathering Average stage 2 Average stage 2 Stage 0-1 Fig. 11
Transport Groups Groups 1 and 2 dominant (excluding teeth) Groups 1 and 2 dominant (excluding teeth) Groups 1 and 2 dominant Fig. 6, 9

 

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