New Mexico Geological Society
Fall Field Conference Guidebook - 52
Geology of Llano Estacado

cover

Spencer G. Lucas and Dana Ulmer-Scholle, eds, 2001, 340 pages.

The history of geological studies in New Mexico began on 22 September 1853 when Swiss geologist Jules Marcou (1824-1898) climbed a hill about 20 km southwest of what is now Tucumcari. Dubbed by Marcou "Pyramid Mountain," this hill exposes red beds at its base, overlain by cliffs of yellow sandstone and capped by a thin shale interval from which poured shells of marine bivalves. Marcou identified these bivalves as the oyster-like Gryphaea (they actually pertain to a closely related genus, subsequently named Texigryphaea), and assigned them a Jurassic age. He thus concluded that the High Plains surface here, and throughout the region, is underlain by Jurassic strata. But the bivalves and the rocks that contain them are actually Cretaceous in age, and Marcou's mistake engendered the first scientific debate about the geology of New Mexico, one that was not resolved during his lifetime. This year, nearly 150 years after Marcou's visit, the attendees of the 52nd Field Conference of the New Mexico Geological Society will visit Pyramid Mountain. And, although the mountain has not changed much since Marcou, our understanding of the rocks exposed on its flanks has, and is a major focus of the field conference and this guidebook. The first day's trip takes us across part of the Llano Estacado to examine Permian, Triassic, Jurassic, Cretaceous and Neogene sedimentary rocks exposed at its margins. In so doing we review the entire section exposed around the staked plains, focusing on problems of stratigraphy, sedimentation, biostratigraphy and magnetostratigraphy. The second day begins by examining Mesozoic strata exposed around erosional outliers of the northern edge of the Llano Estacado in Quay County. The second stop will be to Pyramid Mountain. We will also examine excellent expsoures of the Ogallala Formation at Stop 3. On the final day we will explore the geology of the Canadian River drainage from Tucumcari north to Conchas Dam. Here we contrast differences between the beginning and end of the Late Triassic deposition in the vast Chinle Basin, and the continuity of Middle Jurassic eolian deposition across the American Southwest.

ISBN: 9781585460878

Softcover: $5.00 Buy Now

Table of Contents:

Note —Downloads of the papers below are free. Road logs mini-papers, maps, and other sections are only available in print.

  1. First-day road log, from Tucumcari to the edge of the Llano Estacado at Gruhlkey, Texas, Palo Duro Canyon, Texas, and San Jon Hill, New Mexico
    — Spencer G. Lucas, Adrian P. Hunt, Barry S. Kues, Andrew B. Heckert, and Virginia T. McLemore, pp. 1-23.
  2. Mini-papers:

  3. Paleontology and age of the Upper Triassic Trujillo Formation, east-central New Mexico and West Texas
    — Adrian P. Hunt, pp. 3-4.
  4. Neogene land-mammal "ages" in the Texas Panhandle
    — Spencer G. Lucas and Gary S. Morgan, pp. 8-9.
  5. Abandon the term Dockum!
    — Spencer G. Lucas, pp. 12-13.
  6. The San Jon site, Quay County, New Mexico
    — Vance T. Holliday and Eileen Johnson, pp. 17-18.
  7. Late Albian marine invertebrate fauna from the basal Mesa Rica Sandstone at San Jon Hill, New Mexico
    — Barry S. Kues, pp. 20-21.
  8. The Frio uplift: A Paleozoic-Mesozoic control on sedimentation patterns in east-central New Mexico
    — Adrian P. Hunt and Spencer G. Lucas, pp. 21-22.
  9. Paleocurrents in the Trujillo Formation (Chinle Group; Upper Triassic), east-central New Mexico, and the myth of the Dockum Lake
    — Adrian P. Hunt, Spencer G. Lucas, and Andrew B. Heckert, pp. 22-23.
  10. Second-day road log, from Tucumcari to Mesa Redonda, Pyramid Mountain, Ragland, and Blackwater Draw, New Mexico
    — Spencer G. Lucas, Adrian P. Hunt, Andrew B. Heckert, Barry S. Kues, and Virginia T. McLemore, pp. 25-39.
  11. Mini-papers:

  12. Oasis State Park
    — Virginia T. McLemore, pp. 34-36.
  13. The shovel-tusked Gomphothere Amebelodon (Mammalia: Proboscidea) from the Miocene Ogallala Formation at the Blackwater Draw site, Roosevelt County, New Mexico
    — Gary S. Morgan and Spencer G. Lucas, pp. 37-38.
  14. Laguna Colorado: A forgotten Holocene Lake in Quay County, New Mexico
    — Adrian P. Hunt, pp. 38-39.
  15. The Laramide Tucumcari structural zone, east-central NM
    — Adrian P. Hunt and Spencer G. Lucas, pp. 41-43.
  16. Third-day road log, from Tucumcari to Conchas Dam, New Mexico
    — Spencer G. Lucas, Adrian P. Hunt, Andrew B. Heckert, Barry S. Kues, and Virginia T. McLemore, pp. 41-58.
  17. Mini-papers:

  18. The type area of Bison Bison (Linnaeus, 1758), Canadian River valey, east-central New Mexico
    — Adrian P. Hunt and Spencer G. Lucas, pp. 44-45.
  19. Conchas and Ute reservoirs and water issues in eastern New Mexico
    — Adrian P. Hunt, pp. 48-49.
  20. The first vertebrate track (Brachychirotherium) from the Upper Carnian Garita Crek Formation, east-central New Mexico
    — Adrian P. Hunt and Spencer G. Lucas, pp. 51-52.
  21. Papers:

    Note — To download papers from this guidebook, you will need a PDF viewer like the free Adobe Acrobat Reader.

  22. Raton-Clayton and Ocate volcanic fields (3.79 MB PDF)
    — J. C. Aubele and Crumpler. L. S., pp. 69-76. [ABSTRACT]
  23. Triassic stratigraphy, biostratigraphy and correlation in east-central New Mexico (9.75 MB PDF)
    — Spencer G. Lucas, Andrew B. Heckert, and Adrian P. Hunt, pp. 85-102. [ABSTRACT]
  24. The Moenkopi Formation in east-central New Mexico: stratigraphy and vertebrrate fauna (4.51 MB PDF)
    — Jurgen A. Boy, Rainer R. Schoch, and Spencer G. Lucas, pp. 103-109. [ABSTRACT]
  25. New occurrence of Trilophosaurus (Reptilia: Archosauromorpha) from the Upper Triassic of West Texas and its biochronological significance (5.25 MB PDF)
    — Andrew B. Heckert, Spencer G. Lucas, Robert Kahle, and Kate Zeigler, pp. 115-122. [ABSTRACT]
  26. Lacustrine depositional environments of the Upper Triassic Redonda Formation, east-central New Mexico (9.05 MB PDF)
    — Patricia C. Hester and Spencer G. Lucas, pp. 153-168. [ABSTRACT]
  27. A giant phytosaur (Reptilia: Archosauria) skull from the Redonda Formation (Upper Triassic: Apachean) of east-central New Mexico (4.42 MB PDF)
    — Andrew B. Heckert, Spencer G. Lucas, Adrian P. Hunt, and Jerald D. Harris, pp. 169-176. [ABSTRACT]
  28. Tetrapod footprint ichnofauna of the Upper Triassic Redonda Formation, Chinle Group, Quay County, New Mexico (2.10 MB PDF)
    — Spencer G. Lucas, Adrian P. Hunt, and Martin G. Lockley, pp. 177-180. [ABSTRACT]
  29. The Late Triassic sauropod track reconrd comes into focus: Old legacies and new paradigms (5.25 MB PDF)
    — Martin G. Lockley, Joanna L. Wright, Adrian P. Hunt, and Spencer G. Lucas, pp. 181-190. [ABSTRACT]
  30. Geology of the Ima NW Quadrangle, east-central New Mexico (7.18 MB PDF)
    — Spencer G. Lucas, Gary Weadock, Kenneth K. Kietzke, Adrian P. Hunt, and Barry S. Kues, pp. 191-201. [ABSTRACT]
  31. Jurassic strata in east-central New Mexico and their regional significance (4.61 MB PDF)
    — Spencer G. Lucas and Lee A. Woodward, pp. 203-212. [ABSTRACT]
  32. Cretaceous stratigraphy and biostratigraphy, east-central New Mexico (3.18 MB PDF)
    — Spencer G. Lucas, Barry S. Kues, and Adrian P. Hunt, pp. 215-220. [ABSTRACT]
  33. Albian-Cenomanian depositional cycles transgressed from Chihuahua trough to Western Interior (4.39 MB PDF)
    — R. W. Scott, J. M. Holbrook, M. J. Evetts, and F. E. Oboh-Ikuenobe, pp. 221-228. [ABSTRACT]
  34. Nearshore fauna of the Tucumcari Formation (Lower Cretaceous, Albian), Quay County, New Mexico (13.96 MB PDF)
    — Barry S. Kues and Spencer G. Lucas, pp. 229-249. [ABSTRACT]
  35. Stratigraphy and biostratigraphy of an Upper Cretaceous outlier near Roy, Harding County, New Mexico (3.69 MB PDF)
    — Spencer G. Lucas and Andrew B. Heckert, pp. 251-255. [ABSTRACT]
  36. A review of Pleistocene vertebrate faunas from northeastern New Mexico (12.15 MB PDF)
    — Gary S. Morgan, Spencer G. Lucas, Paul L. Sealey, and Adrian P. Hunt, pp. 265-284. [ABSTRACT]
  37. Late Pleistocene mammoths (Mammathus Columbi) from Mesa Redonda, Quay County, east-central NM (4.73 MB PDF)
    — Gary S. Morgan, Spencer G. Lucas, and Mark E. Gordon, pp. 285-292. [ABSTRACT]