Paleocene deposits, San Juan Basin, N. Mex.

p. 297-316, [10] leaves of plates (2 folded) : ill, map ; 24 cm.Includes bibliographical references.Itinerary -- Structural relationships; location of exposures -- Pre-Puerco formations. Conglomeratic sandstone with fossil logs. Shales with dinosaurs, upper horizon. Lower conglomerate. Shales with dinosaurs, lower horizon. Age of the Ojo Alamo beds -- The Puerco Formation. Basal uncomformity. The Puerco sediments. 1. Ojo Alamo section. 2. Kimbetoh Arroyo section. Thickness of the Puerco. Fossil levels; origin of the Puerco sediments -- The Torrjon Formation. The Torrjon sediments. Torrejon fossil levels. Thickness of the Torrejon. Torrejon-Wasatch relationships. Origin of the Torrejon sediments -- Age of the Puerco and Torrejon -- "Nacimiento" as a group name -- Summary -- Collecting localities."The more important stratigraphic results may be summarized as follows: 1. Separation of the pre-Puerco beds into several members which are, in descending order, a heavy conglomeratic sandstone with much fossil wood, a series of clays with channel sandstones, a conglomerate and a series of dove-colored clays, red-banded near the top. The two conglomeratic members have disconformities at their bases. Dinosaurs occur, especially at two levels separated by the lower conglomerate. More or less of this series of beds may be correlateable with the Animas formation. 2. Complete confirmation of Barnum Brown's observation regarding the unconformable relationship of the Puerco with respect to the conglomeratic sandstone with fossil logs on which it rests. A topography in low relief was developed on the surface of this sandstone previous to the deposition of the Puerco clays, which cover up these hills and valleys. 3. Accurate location of the two Puerco fossil levels and demonstration of the fact that Polymastodon is confined to the uppermost of the two levels. For their position see sections A and B, Fig. 2. 4. Measurement of the thickness of the Puerco on continuous exposures from the unconformity at its base to the level of the first occurrence of Torrejon fossils. 5. Discovery of fossil plants in the Puerco. 6. Accumulation of data which seem to prove the fluviatile origin of the Puerco sediments. 7. Discovery of a new fossil horizon in the Torrejon, 100 feet below the horizon from which fossils had hitherto been obtained. 8. Finding of Torrejon fossils at still lower levels (see sections). 9. Location of the Torrejon levels with reference to those of the Puerco (see actions A and B, Fig. 2). 10. Correlation of the Rio Puerco and Arroyo Torrejon sections published by Dr. Gardner of the U.S. Geological Survey with the sections measured by the American Museum party. 11. Accumulation of data which seem to prove the fluviatile origin of the Torrejon sediments"--P. 314-315