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Berwind Canyon

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Astropectinid sea star from Berwind Canyon, Colorado. Original mold of an astropectinid sea star (NMMNH P-78593) collected from the top of the Pierre Shale at Berwind Canyon, Colorado (NMMNH Locality L-10795; see Berry, 2010, 2016). In this paper, this sea star is assigned to the genus Lophidiaster as defined by Hess (1955). Photograph by K. Berry.
Published: 01 June 2017
Figure 5. Astropectinid sea star from Berwind Canyon, Colorado. Original mold of an astropectinid sea star (NMMNH P-78593) collected from the top of the Pierre Shale at Berwind Canyon, Colorado (NMMNH Locality L-10795; see Berry, 2010 , 2016 ). In this paper, this sea star is assigned
Published: 01 January 2007
DOI: 10.1130/2008.2437(12)
..., our study sections in southwestern South Dakota are most similar to, and may correlate with, the recently documented 68 Ma impactite within the Vermejo Formation of Berwind Canyon in southeastern Colorado. If this correlation is correct, the size of the ejecta within the Fox Hills and Vermejo...
Journal Article
Journal: Geology
Published: 01 March 1995
Geology (1995) 23 (3): 281–284.
... in proportion to the intensity of shock metamorphism exhibited by each zircon. The age and zircon shock features establish a strong temporal and genetic link with K-T distal ejecta from the fireball layer at the Berwind canyon site in the Raton basin, Colorado, where texturally similar zircons from a previous...
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Stratigraphy of the Raton Basin, south-central Colorado. Composite geologic column for the Maastrichtian strata in Berwind Canyon, which merges with Road Canyon (not illustrated in Fig. 1) to the immediate west (Raton Basin, south-central Colorado; NMMNH Localities L-10780 through L-10787, and L-10794; see Fig. 1). The Campanian–Maastrichtian stage boundary, which was located using high-resolution ammonite and inoceramid biostratigraphy, is located about 100 m below the top of the Pierre Shale at Berwind Canyon (Berry, 2016).
Published: 01 June 2017
Figure 3. Stratigraphy of the Raton Basin, south-central Colorado. Composite geologic column for the Maastrichtian strata in Berwind Canyon, which merges with Road Canyon (not illustrated in Fig. 1 ) to the immediate west (Raton Basin, south-central Colorado; NMMNH Localities L-10780 through L
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 (a) Percentage of inertinite (charred material) across the K–T boundary following a transect of sites across North America, measured in situ in polished blocks of sediment. (b) Quantity of >150 μm sized charcoal particles across the K–T boundary (number of charred particles per gram of sediment). Three intervals at Madrid East South and Berwind Canyon have been truncated (bars containing asterisks), as they contain some very large peaks in abundance of charcoal. The large peak at Madrid East South is 19 707 particles of charcoal per gram of sediment and the largest peak at Berwind Canyon is 60 988 particles of charcoal per gram of sediment. (c) Quantity of <150 μm sized charcoal particles across the K–T boundary (number of charred particles per gram of sediment).
Published: 01 July 2005
gram of sediment). Three intervals at Madrid East South and Berwind Canyon have been truncated (bars containing asterisks), as they contain some very large peaks in abundance of charcoal. The large peak at Madrid East South is 19 707 particles of charcoal per gram of sediment and the largest peak
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Comparison of the δ13C record across the K–T boundary in terrestrial sections in North America. When not reported, the δ13C values and the stratigraphic position of samples were estimated from figures in Schimmelmann and DeNiro (1984), Arens and Jahren (2000), Beerling et al. (2001), and Gardner and Gilmour (2002). All sections are correlated at the top of the iridium anomaly layer (gray dashed line). Asterisk marks the location of the most negative δ13C values interpreted to be associated with K–T boundary. Note that only the Knudsen’s Farm, Brownie Butte, and Berwind Canyon sections preserve the most negative δ13C values immediately (<10 cm) above the K–T boundary claystone; in all other sections, the most negative δ13C values occur several decimeters above the K–T boundary. For legend, see Fig. 4.
Published: 31 May 2007
. ( 2001 ), and Gardner and Gilmour ( 2002 ). All sections are correlated at the top of the iridium anomaly layer (gray dashed line). Asterisk marks the location of the most negative δ 13 C values interpreted to be associated with K–T boundary. Note that only the Knudsen’s Farm, Brownie Butte, and Berwind
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Affinity of an early late-Maastrichtian astropectinid sea star from the Raton Basin to Late Cretaceous–Early Paleogene European Lophidiaster. A, Close-up of apparently smooth inferomarginal ossicles of an astropectinid sea star (NMMNH P-78593) from the top of the Pierre Shale at Berwind Canyon, Colorado (NMMNH Locality L-10795). Note the conspicuous absence of large, horseshoe-shaped spine tubercles on these apparently smooth inferomarginal ossicles, which supports the taxonomic assignment of NMMNH P-78593 to the genus Lophidiaster (Hess, 1955). Photograph by K. Berry. B, Example of a smooth marginal ossicle from the type species (top left) of the genus Lophidiaster (L. pygmaeus; adapted from Spencer, 1913, plate 11, fig. 20; plate 16, fig. 18). Spencer (1913) originally suggested that the apparently smooth marginal ossicles, such as the one reproduced here (top left), were superomarginal ossicles; however, Jagt (2000) later referred these to the inferomarginal series of L. pygmaeus. Example of a smooth inferomarginal ossicle (right) of L. aff. pygmaeus (redrawn from Rasmussen, 1972, plate 3, figs. 27a–b). Illustrations by the author.
Published: 01 June 2017
at Berwind Canyon, Colorado (NMMNH Locality L-10795). Note the conspicuous absence of large, horseshoe-shaped spine tubercles on these apparently smooth inferomarginal ossicles, which supports the taxonomic assignment of NMMNH P-78593 to the genus Lophidiaster ( Hess, 1955 ). Photograph by K. Berry. B
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A biostratigraphically important leaf fossil from the Vermejo-Raton megafloras. A, “Cissites” panduratus (NMMNH P-78592) from the upper coal zone (Paleocene) of the Raton Formation in Road Canyon, Colorado, which merges with Berwind Canyon to the east (see Fig. 1; NMMNH Locality L-10794). Weakly lobed leaves, such as this one, from the upper coal zone of the Raton Formation in south-central Colorado, originally had been referred to “Acer” fragilis by Knowlton (1917) and Lee (1917); however, this taxon was later synonymized with “C.” panduratus by Wolfe and Tanai (1987)—a taxonomic revision that still stands (Manchester, 2014). B, Original figures of the deeply lobed type (left) and plesiotype (right) specimens of “C.” panduratus from the Vermejo and Ripley Formations, respectively (reproduced from Knowlton, 1917, plate 69, fig. 10; Berry, 1925, plate 14, figs. 2–3). C, Original figure of the type specimen of “C.” puilasokensis from the Puilasok megaflora (Paleocene) of western Greenland (reproduced from Heer, 1883, plate 107, fig. 8), which is now known to be early Paleocene in age (see LePage et al., 2005). In the Raton Basin, deeply lobed leaves essentially identical to this morphotype have been attributed to “C.” panduratus and are locally abundant in Wolfe and Upchurch’s (1987) early Paleocene megafloral assemblage in the Raton Formation (Upchurch, personal communication, 2014). Consequently, “C.” puilasokensis and Wolfe and Upchurch’s (1987) early Paleocene assemblage, which is dominated by “C.” panduratus, are now known to be essentially equivalent in age (Fig. 1).
Published: 01 June 2017
Figure 6. A biostratigraphically important leaf fossil from the Vermejo-Raton megafloras. A , “Cissites” panduratus (NMMNH P-78592) from the upper coal zone (Paleocene) of the Raton Formation in Road Canyon, Colorado, which merges with Berwind Canyon to the east (see Fig. 1 ; NMMNH Locality
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Appearance and texture of zircon in meteorite impact structures. (1, 2) Shocked zircon crystals from charnockite in Vredefort structure, modified from Kamo et al. (1996), 1 = SEM, 2 = TL, crossed nicols. (3) Euhedral zircon with three sets of planar deformation features; Manicouagan impact crater, modified from Bohor et al. (1993); SEM. (4) Multiple sets of planar deformation features in shocked zircon in Copper Cliff rhyolite, Sudbury structure, from F. Corfu (unpublished data), TL. (5, 6) Zircons from post-impact granite from Vredefort structure, modified from Gibson et al. (1997); 5 – euhedral crystal without shock-related features enclosing a fractured core (RL); 6 – zircon core with three sets of planar deformation features surrounded by post-impact unfractured zircon rim (CL). (7) granular zircon grain from granophyric part of melt-breccia dyke, Vredefort structure, modified from Kamo et al. (1996), SEM. (8, 9) polycrystalline grains with degassing and melting textures; 8 – K/T distal impact ejecta, Berwind Canyon, Colorado, modified from Bohor et al. (1993); SEM; 9 – Onaping Formation (impact melt), Sudbury structure, modified from Krogh et al. (1996), SEM.
Published: 02 January 2003
structure, modified from Kamo et al. (1996) , SEM. (8, 9) polycrystalline grains with degassing and melting textures; 8 – K/T distal impact ejecta, Berwind Canyon, Colorado, modified from Bohor et al. (1993) ; SEM; 9 – Onaping Formation (impact melt), Sudbury structure, modified from Krogh et al. (1996
Journal Article
Published: 01 June 2017
Rocky Mountain Geology (2017) 52 (1): 1–16.
...Figure 5. Astropectinid sea star from Berwind Canyon, Colorado. Original mold of an astropectinid sea star (NMMNH P-78593) collected from the top of the Pierre Shale at Berwind Canyon, Colorado (NMMNH Locality L-10795; see Berry, 2010 , 2016 ). In this paper, this sea star is assigned...
FIGURES
First thumbnail for: New paleontological constraints on the paleogeogra...
Second thumbnail for: New paleontological constraints on the paleogeogra...
Third thumbnail for: New paleontological constraints on the paleogeogra...
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Late Campanian–early Maastrichtian paleogeography of the Western Interior Seaway (WIS; modified from Slattery et al., 2015). Key to numbered records of “Cissites” puilasokensis or “Cissites” panduratus: (1)Heer (1883): early Paleocene; (2)Knowlton (1917), Lee (1917), Wolfe and Upchurch (1987): late Maastrichtian–early Paleocene; (3)Knowlton (1917), Lee (1917), Wolfe and Tanai (1987): early Paleocene; (4)Berry (1922, 1925): late Campanian or early Maastrichtian; (5)Brown (1939): late Maastrichtian; (6)Barclay et al. (2003), Nichols and Johnson (2008): early Paleocene; (7)Johnson and Hickey (1990), Nichols and Johnson (2008): late Maastrichtian. When reviewing these records, which are arranged more or less chronologically, please note that Berry (1922, p. 171) erroneously reported that “C.” panduratus initially had been described from the Mesaverde Formation (no locality given), but that he later corrected this report by acknowledging that, at the time, “C.” panduratus was known only from the Vermejo and Ripley Formations and not the Mesaverde Formation (Berry, 1925, p. 24). Key to lettered paleogeographic features: (a) northern shoreline of the WIS according to Erickson (1978, 1999), Lillegraven and Ostresh (1990), Robinson Roberts and Kirschbaum (1995), and Kennedy et al. (1998); (b) southern shoreline of the WIS according to Lehman (1987) and Blakey (2014); (c) dispersal route for land plants between Asia and western North America in the late Maastrichtian (Peppe et al., 2007; Zakharov et al., 2011); (d) eastern margin of the WIS and general location (e) of a large island or archipelago according to Williams and Stelck (1975). Local paleogeographic map (modified from Miller and McKinney, 2016): Position of western shoreline of the WIS during the Baculites clinolobatus ammonite biozone as reconstructed by Cobban et al. (1994), Landman and Cobban (2003), Slattery et al. (2015), and Miller and McKinney (2016). New data from the Raton Basin, which are discussed in the text, indicate that this shoreline should be shifted about 100 km farther west (white arrow) to a geographic location in the immediate vicinity of Berwind Canyon, Colorado.
Published: 01 June 2017
, indicate that this shoreline should be shifted about 100 km farther west (white arrow) to a geographic location in the immediate vicinity of Berwind Canyon, Colorado.
Journal Article
Published: 01 July 2005
Journal of the Geological Society (2005) 162 (4): 591–602.
... gram of sediment). Three intervals at Madrid East South and Berwind Canyon have been truncated (bars containing asterisks), as they contain some very large peaks in abundance of charcoal. The large peak at Madrid East South is 19 707 particles of charcoal per gram of sediment and the largest peak...
FIGURES
First thumbnail for: Constraints on the thermal energy released from th...
Second thumbnail for: Constraints on the thermal energy released from th...
Third thumbnail for: Constraints on the thermal energy released from th...
Journal Article
Journal: Geology
Published: 01 December 2003
Geology (2003) 31 (12): 1061–1064.
... Place) noncharred organic material, commonly as vitrinite laminae ( Fig. 2B ). Vitrinite laminae are also recorded in the upper claystone at southern sites ( Izett, 1990 : Berwind Canyon, Clear Creek North, and Madrid East, Colorado) and at northern sites ( Sweet et al., 1999 : Knudsen's Coulee, Alberta...
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First thumbnail for: Fireball passes and nothing burns—The role of ther...
Second thumbnail for: Fireball passes and nothing burns—The role of ther...
Journal Article
Published: 31 May 2007
Canadian Journal of Earth Sciences (2007) 44 (4): 529–542.
.... ( 2001 ), and Gardner and Gilmour ( 2002 ). All sections are correlated at the top of the iridium anomaly layer (gray dashed line). Asterisk marks the location of the most negative δ 13 C values interpreted to be associated with K–T boundary. Note that only the Knudsen’s Farm, Brownie Butte, and Berwind...
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First thumbnail for: High-resolution organic carbon isotope record acro...
Second thumbnail for: High-resolution organic carbon isotope record acro...
Third thumbnail for: High-resolution organic carbon isotope record acro...
Journal Article
Published: 10 January 2018
Seismological Research Letters (2018) 89 (2A): 570–576.
... at Sugarite Mine 3, New Mexico (36°56′39.89″ N, 104°22′32.40″ W), and Berwind Canyon, New Mexico (37°17′43.79″ N, 104°37′39.90″ W), were unsuitable for searching for faults. Road cuts expose the K–Pg layer in Long’s Canyon within Trinidad State Park and at nearby Madrid Canyon (Fig.  1b...
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First thumbnail for: Remote Faulting Triggered by Strong Seismic Waves ...
Second thumbnail for: Remote Faulting Triggered by Strong Seismic Waves ...
Third thumbnail for: Remote Faulting Triggered by Strong Seismic Waves ...
Journal Article
Published: 10 December 2010
Canadian Journal of Earth Sciences (2011) 48 (2): 107–116.
... ejecta at the K–T (Cretaceous–Tertiary) boundary layer at the Berwind Canyon site in the Raton Basin, Colorado. Data points define a linear array on a concordia plot that intersects concordia at the primary age and trends towards the age of impact. The results show a correlation between the degree of U...
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First thumbnail for: Comparison of structures in zircons from lunar and...
Second thumbnail for: Comparison of structures in zircons from lunar and...
Third thumbnail for: Comparison of structures in zircons from lunar and...
Journal Article
Published: 02 January 2003
Reviews in Mineralogy and Geochemistry (2003) 53 (1): 469–500.
... structure, modified from Kamo et al. (1996) , SEM. (8, 9) polycrystalline grains with degassing and melting textures; 8 – K/T distal impact ejecta, Berwind Canyon, Colorado, modified from Bohor et al. (1993) ; SEM; 9 – Onaping Formation (impact melt), Sudbury structure, modified from Krogh et al. (1996...
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First thumbnail for: Atlas of Zircon Textures
Second thumbnail for: Atlas of Zircon Textures
Third thumbnail for: Atlas of Zircon Textures