Laramie
Description
Source: Wikipédia
La Formation de Laramie est une formation géologique datant du Maastrichien, dernier étage du Crétacé supérieur. Elle a été nommée par Clarence King en 1876 pour des affleurements situés dans le nord du Colorado, aux États-Unis.
La formation est située sur les bords du bassin de Denver et a une épaisseur de 120 à 160 mètres sur son versant ouest et de 70 à 100 mètres sur son versant est. Elle repose en concordance sur les grès de la Formation de Fox Hills et est recouverte en discordance par les conglomérats de la Formation Arapahoe. La formation peut être divisée en un étage inférieur (sans nom) contenant des couches de grès, d'argile et de charbon et un étage supérieur (sans nom lui aussi) composé principalement de 90 à 190 m de mudstones de couleur terne, de grès et de minces couches de charbon. Des concrétions ferrugineuses nodulaires trouvées dans les mudstones contiennent des restes de plantes. Le charbon et l'argile du site ont eu autrefois une grande importance économique. La formation de Laramie correspond à une ancienne plaine côtière avec des zones marécageuses. Une partie des matériaux retrouvés dans les grès provient des volcans situés loin à l'ouest.
Découvertes
Source: The Paleobiology Database
Site(s) correspondant(s) à cette formation: 15
Ken's Site : Colorado - Weld 717 42675 61518 apparently near Crow Creek in "central Weld County"
the site "spans an area of about 100m2" (Wilson et al. 2010)- Owl Creek (UCM Loc. 80013) : Colorado - Weld 12319 13266 sec. 22, T11N, R66W, on Owl Creek, a small tributary of Lone Tree Creek, Weld Co.
- Bijou Creek (USG&GS) : Colorado - Adams 9274 12304 12319 13266 14442 17555 53327 53400 63646 63647 along Bijou Creek, probably in at least two places, but exact localities unknown; L&W describe the locality as "evidently from the watershed between the South Platte River and Lodge Pole Creek, Colorado"
- Hadrosauridae identifié comme Cionodon arctatus n. gen. n. sp.
- Ceratopsidae identifié comme Polyonax mortuarius n. gen. n. sp.
- Edmontosaurus regalis
- 2 miles north of Briggsdale : Colorado - Weld 13266 52428 64556 ca. 2 mi. N of Briggsdale
- Locality V-1, East Bijou Creek : Colorado - Adams 13266 83728 S end of East Bijou Creek; NW 1/4, sec. 33, T7S, R59W. Locality V-1
- Leyden Gulch (DMNH Loc. 1282) : Colorado - Jefferson 13266 29242
- 12th Street tracksite (upper) : Colorado - Jefferson 13266 29242 near 12th Street, Colorado School of Mines
- Marshall tracksite (DMNH Loc. 871) : Colorado - Boulder 13266 29242 in vicinity of Marshall, about 12 km N of Leyden Gulch
- Hamilton Farm (UCM Loc. 81062) : Colorado - Boulder 13266
- Hunter-Douglas : Colorado - Adams 13266
- Leyden Gulch tracksite : Colorado - Jefferson 29242 54850 80662 "immediately adjacent" to DMNH Triceratops site
- Natural Fort (UCM Loc. 78193) : Colorado - Weld 13266 "a large outcrop of ~0.4 km2 and up to 12 m relief... immediately east of Interstate 25 near northbound exit 293, where there was once a rest area"
- 12 miles northeast of Briggsdale : Colorado - Weld 52428 64556 12 miles northeast of Briggsdale
- Pawnee (UCM) : Colorado - Weld 13266 unspecified locality presumably within Pawnee National Grasslands
- Cherryvale tracksite : Colorado - Boulder 85491 inferred to be near Cherryvale Trail, near Marshall, S of Boulder
Publication(s)
La base comprend 20 publication(s).
Source: The Paleobiology Database
- ↑1 2 K. Carpenter. 1979. Vertebrate fauna of the Laramie Formation (Maestrichtian), Weld County, Colorado. Contributions to Geology, University of Wyoming 17(1):37-49
- ↑1 J. D. Gardner. 2000. Albanerpetontid amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America. Geodiversitas 22(3):349-388
- ↑1 D. B. Weishampel and J. B. Weishampel. 1983. Annotated localities of ornithopod dinosaurs: implications to Mesozoic paleobiogeography. The Mosasaur 1:43-87
- ↑1 2 3 R. S. Lull and N. E. Wright. 1942. Hadrosaurian dinosaurs of North America. Geological Society of America Special Paper 40:1-242 (https://doi.org/10.1130/spe40-p1)
- ↑1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 K. Carpenter and D. B. Young. 2002. Late Cretaceous dinosaurs from the Denver Basin, Colorado. Rocky Mountain Geology 37(2):237-254 (https://doi.org/10.2113/11)
- ↑1 2 E. D. Cope. 1874. Report on the stratigraphy and Pliocene vertebrate paleontology of northern Colorado. Bulletin of the United States Geological and Geographical Survey of the Territories 1(1):9-22
- ↑1 E. D. Cope. 1889. The horned Dinosauria of the Laramie. The American Naturalist 23(272):715-717
- ↑1 J. B. Hatcher, O. C. Marsh, and R. S. Lull. 1907. The Ceratopsia. Monographs of the United States Geological Survey 49:1-198 (https://doi.org/10.5962/bhl.title.60500)
- ↑1 O. P. Hay. 1908. The fossil turtles of North America. Carnegie Institution of Washington Publication 75:1-568 (https://doi.org/10.5962/bhl.title.21745)
- ↑1 E. D. Cope. 1875. Report on the vertebrate paleontology of Colorado. Annual Report of the United States Geological and Geographical Survey of the Territories 1873:427-533
- ↑1 J. H. Johnson. 1931. The paleontology of the Denver quadrangle, Colorado. Colorado Scientific Society, Proceedings 12(11):355-378
- ↑1 E. D. Cope. 1874. Review of the Vertebrata of the Cretaceous Period found west of the Mississippi River. Bulletin of the United States Geological and Geographical Survey of the Territories, First Series 2:3-48
- ↑1 E. D. Cope. 1875. The Vertebrata of the Cretaceous formations of the west. Report of the United States Geological and Geographical Survey of the Territories 2:1-303 (https://doi.org/10.5962/bhl.title.61834)
- ↑1 2 3 4 W. C. Toepelman. 1926. Notes on the Laramie Formation in central Weld County, Colorado. The Journal of Geology 34(8):834-835 (https://doi.org/10.1086/623371)
- ↑1 2 R. W. Brown. 1943. Cretaceous-Tertiary boundary in the Denver Basin, Colorado. Bulletin of the Geological Society of America 54:65-86 (https://doi.org/10.1130/gsab-54-65)
- ↑1 2 C. H. Dane and W. G. Pierce. 1936. Dawson and Laramie formations in southeastern part of Denver Basin, Colorado. Bulletin of the American Association of Petroleum Geologists 20(10):1308-1328
- ↑1 2 3 4 5 6 7 M. G. Lockley and A. P. Hunt. 1995. Ceratopsid tracks and associated ichnofauna from the Laramie Formation (Upper Cretaceous: Maastrichtian) of Colorado. Journal of Vertebrate Paleontology 15(3):592-614 (https://doi.org/10.1080/02724634.1995.10011251)
- ↑1 2 M. G. Lockley, M. Matsukawa, and I. Obata. 1989. Dinosaur tracks and radial cracks: unusual footprint features. Bulletin of the National Science Museum, Tokyo, Series C 15(4):151-160
- ↑1 J. Wright and M. G. Lockley. 2001. Dinosaur and turtle tracks from the Laramie/Arapahoe formations (Upper Cretaceous), near Denver, Colorado, USA. Cretaceous Research 22:365-376 (https://doi.org/10.1006/cres.2001.0262)
- ↑1 2 M. G. Lockley, B. Simmons, and S. E. Hirschfeld. 2018. A new dinosaur track locality in the Late Cretaceous (Maastrichtian) Laramie Formation of Colorado. Fossil Record 6. New Mexico Museum of Natural History and Science Bulletin 79:395-406
Galerie d'image
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