University of Virginia Library

Studies in Geology, Geography, and Biology

Mention has been made already of the various military and scientific
reconnaissances into the Chaco area up to 1902. Along non-archaeologic
lines the scientific studies were chiefly for details of terrain
and structural geology. No collections of botanical, zoologic, or
paleontologic materials were made in the Chaco Canyon area until
1902.[39] Professor R. E. Dodge, at the turn of the century, carried on
geologic and geographic investigations around Pueblo Bonito for the
Hyde Expedition during three field sessions. In 1902, George Pepper
sent to the American Museum some dinosaur bones from the vicinity
of Ojo Alamo, to the northwest of Pueblo Bonito. In 1904, Barnum
Brown, of the American Museum of Natural History, made the first
extensive paleontologic collections in the Ojo Alamo area and formation.
By 1907, F. C. Schrader, James H. Gardner, and M. K. Shaler
had made several paleontologic and economic reconnaissances of the
western Chaco drainage basin. A search for commercial deposits of
coal has been the mainspring of geologic investigations in this area ever
since the presence of coal was verified by the Wheeler, Hayden, and
other government expeditions of the nineteenth century. Some prospecting
has been carried out also for petroleum, which occurs in various
portions of the San Juan basin near Farmington, Shiprock, and
Seven Lakes (on the Chaco Plateau). Noteworthy among the later
paleontologic and geologic collecting and mapping parties were those
of: Gardner and Gidley, in 1908 and 1909; H. E. Gregory and J. E.

Pogue, in 1911; W. J. Sinclair and W. Granger, in 1912 and 1913; C.
M. Bauer, J. B. Reeside, Jr., and H. R. Bennett, in 1915; Reeside and
F. R. Clark, in 1916; Reeside and H. Bassler, in 1917; Reeside and C.
E. Dobbin, in 1920; C. H. Sternberg, in 1921; Reeside, in 1923; C. H.
Dane, J. D. Sears, and C. B. Hunt, 1928-1931; and C. W. Gilmore, in
1929.[40]

Physiographic and hydrographic studies in the Chaco Canyon area
began with Professor Dodge (associated with the Hyde Expedition)
who noted evidence of changes in erosion and sedimentation near Pueblo
del Arroyo and elsewhere in the canyon area.[41] James Gardner, in 1906
and 1907, observed the formation of mud and sand concretions in the
Chaco arroyo. Herbert Gregory studied the water supply of the southwestern
Chaco area in 1911. During the National Geographic Society
excavations in the canyon, 1921-1927, trenches were dug which revealed
former channels and denudational surfaces. At this same period, Dr.
Kirk Bryan, of Harvard University, studied the history of denudation,
sedimentation, and erosion in the canyon. In 1927, New Mexico State
Engineer Herbert W. Yeo commenced investigations in the San Juan
Basin, including the Chaco drainage. Beginning in 1928, Dr. Reginald
Fisher has devoted much time to meteorologic and hydrologic studies in
the Chaco area. In 1934, William Chauvenet experimented in erosion
control for the protection of several archaeologic sites.[42] Dr. Ernst Antevs,
Dr. Malcolm Bissell, and Dr. Donald Brand studied recent sedimentation
and erosion in the canyon in connection with the University of
New Mexico Field Sessions of 1936. Possible movement of the Threatening
Rock, back of Pueblo Bonito, is being observed (since 1933) by Dr.
J. Keur, of Long Island University.[43]

Practically no investigations have been made of the weather and
climate, soils, vegetation, and fauna of the Chaco Canyon area. Only
broken meteorologic records are available up to June of 1932. Since
then, reports on maxima and minima temperatures, precipitation and
wind direction, have been sent in monthly to the Weather Bureau Office
at Albuquerque by the Monument custodian. Flow in the Chaco arroyo
has been gaged at the Pueblo Bonito bridge for the last few years also.

No soil study has ever been made by a trained pedologist. Botanists,
in general, have eschewed the area, although Newberry collected along
Cañon Largo in 1857; Matthews around Ft. Definance in 1882; and collections
were made on the margins of the Chaco area by the botanists
of the Wheeler and Hayden surveys. Miss Sara Goddard, in 1929, obtained
a short list of Zuñi names of plants in the Chaco Canyon; and,
in 1935 and 1936, Francis Elmore compiled a Najavo ethnobotanical
check list for the area. The only zoologist known to have been in the
Chaco Canyon is Vernon Bailey, who visited Pueblo Bonito in October
of 1908; although J. S. Ligon followed along the Continental Divide to
the east in 1913. During the last two years some attempt has been
made at bird banding in the Chaco Canyon by the Monument Custodians.
In 1936, a National Park Service specialist in rodent control,
Mr. A E. Borell, worked in the canyon for a brief period. No studies of
any description have been made of reptilian, arthropod, and lower
forms of life in the canyon. [A certain amount of biological study has
been carried on during the last two years in the western Chaco area by
the Navajo Biological Survey, of the Department of Agriculture's Soil
Conservation Service.]