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, and some other sections of recent guidebooks are only available in print.

Front Matter: (includes Dedication, President's Message, & Conference Organizer's Message)

Download (658 KB PDF)

Roadlogs: (each includes listed mini-papers)

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 (6.50 MB PDF)
— Spencer G. Lucas, Adrian P. Hunt, Barry S. Kues, Andrew B. Heckert, and Virginia T. McLemore, pp. 1-23. https://doi.org/10.56577/FFC-52.1 [SUMMARY]

Mini-papers:

Paleontology and age of the Upper Triassic Trujillo Formation, east-central New Mexico and West Texas
— Adrian P. Hunt, pp. 3-4.
Neogene land-mammal "ages" in the Texas Panhandle
— Spencer G. Lucas and Gary S. Morgan, pp. 8-9.
Abandon the term Dockum!
— Spencer G. Lucas, pp. 12-13.
The San Jon site, Quay County, New Mexico
— Vance T. Holliday and Eileen Johnson, pp. 17-18.
Late Albian marine invertebrate fauna from the basal Mesa Rica Sandstone at San Jon Hill, New Mexico
— Barry S. Kues, pp. 20-21.
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.
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.
Second-day road log, from Tucumcari to Mesa Redonda, Pyramid Mountain, Ragland, and Blackwater Draw, New Mexico (3.93 MB PDF)
— Spencer G. Lucas, Adrian P. Hunt, Andrew B. Heckert, Barry S. Kues, and Virginia T. McLemore, pp. 25-39. https://doi.org/10.56577/FFC-52.25 [SUMMARY]

Mini-papers:

Oasis State Park
— Virginia T. McLemore, pp. 34-36.
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.
Laguna Colorado: A forgotten Holocene Lake in Quay County, New Mexico
— Adrian P. Hunt, pp. 38-39.
The Laramide Tucumcari structural zone, east-central NM
— Adrian P. Hunt and Spencer G. Lucas, pp. 41-43.
Third-day road log, from Tucumcari to Conchas Dam, New Mexico (3.62 MB PDF)
— Spencer G. Lucas, Adrian P. Hunt, Andrew B. Heckert, Barry S. Kues, and Virginia T. McLemore, pp. 41-53. https://doi.org/10.56577/FFC-52.41 [SUMMARY]

Mini-papers:

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.
Conchas and Ute reservoirs and water issues in eastern New Mexico
— Adrian P. Hunt, pp. 48-49.
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.
Conchas Lake State Park
— Virginia T. McLemore, pp. 52-53.

Roadlog References:

Download (1.80 MB PDF)

Papers:

Raton-Clayton and Ocate volcanic fields (2.32 MB PDF)
— J. C. Aubele and Crumpler. L. S., pp. 69-76. https://doi.org/10.56577/FFC-52.69 [ABSTRACT]
Triassic stratigraphy, biostratigraphy and correlation in east-central New Mexico (5.05 MB PDF)
— Spencer G. Lucas, Andrew B. Heckert, and Adrian P. Hunt, pp. 85-102. https://doi.org/10.56577/FFC-52.85 [ABSTRACT]
The Moenkopi Formation in east-central New Mexico: stratigraphy and vertebrrate fauna (2.08 MB PDF)
— Jurgen A. Boy, Rainer R. Schoch, and Spencer G. Lucas, pp. 103-109. https://doi.org/10.56577/FFC-52.103 [ABSTRACT]
The Late Triassic sauropod track reconrd comes into focus: Old legacies and new paradigms (2.89 MB PDF)
— Martin G. Lockley, Joanna L. Wright, Adrian P. Hunt, and Spencer G. Lucas, pp. 181-190. https://doi.org/10.56577/FFC-52.181 [ABSTRACT]
Geology of the Ima NW Quadrangle, east-central New Mexico (2.86 MB PDF)
— Spencer G. Lucas, Gary Weadock, Kenneth K. Kietzke, Adrian P. Hunt, and Barry S. Kues, pp. 191-201. https://doi.org/10.56577/FFC-52.191 [ABSTRACT]
Cretaceous stratigraphy and biostratigraphy, east-central New Mexico (1.73 MB PDF)
— Spencer G. Lucas, Barry S. Kues, and Adrian P. Hunt, pp. 215-220. https://doi.org/10.56577/FFC-52.215 [ABSTRACT]
Albian-Cenomanian depositional cycles transgressed from Chihuahua trough to Western Interior (2.57 MB PDF)
— R. W. Scott, J. M. Holbrook, M. J. Evetts, and F. E. Oboh-Ikuenobe, pp. 221-228. https://doi.org/10.56577/FFC-52.221 [ABSTRACT]
A review of Pleistocene vertebrate faunas from northeastern New Mexico (5.93 MB PDF)
— Gary S. Morgan, Spencer G. Lucas, Paul L. Sealey, and Adrian P. Hunt, pp. 265-284. https://doi.org/10.56577/FFC-52.265 [ABSTRACT]
Late Pleistocene mammoths (Mammathus Columbi) from Mesa Redonda, Quay County, east-central NM (1.90 MB PDF)
— Gary S. Morgan, Spencer G. Lucas, and Mark E. Gordon, pp. 285-292. https://doi.org/10.56577/FFC-52.285 [ABSTRACT]

Back Matter: (usually includes a stratigraphic column and/or correlation chart)

Download (611 KB PDF)


Recommended Guidebook Citation:

  1. Lucas, Spencer G.;Ulmer-Scholle, Dana; [eds.], 2001, Geology of Llano Estacado, New Mexico Geological Society, Guidebook, 52nd Annual Field Conference, 340 pp. ISBN: 9781585460878 https://doi.org/10.56577/FFC-52