RECONNAISSANCE IN THE RIO GRANDE COAL FIELDS OF TEXAS. 
By Thomas Wayland Vaughan. 
INTRODUCTION. 
One of the most important economic questions with which Texas 
has to deal is that of coal suppty. Although it embraces 250,000 
square miles of territory, and is by far the largest State in the Union, 
in 1897 it stood nineteenth in the scale of coal producers. For manu- 
facturing enterprises and railroads coal is one of the first requisites; 
therefore in the following paper an attempt has been made to state all 
that, is known of the coal fields of the Rio Grande region. Two recon- 
naissance trips made jointly with Mr. T. W. Stanton, under instruc- 
tions received from Mr. R. T. Hill, during the field season of 1895; a 
reconnaissance made in 1898 in company Avith Prof. William L. Bray, 
of the University of Texas, who was studying the flora of western 
Texas; and a certain portion of the notes accumulated while mapping 
the geology of the Brackett quadrangle, as assistant to Mr. R. T. Hill, 
and later while mapping the geology of the Uvalde quadrangle, serve as 
a basis for this report, but all available information has been utilized. 
The fact that this report is, as a whole, the result of reconnaissance 
work and that it is not based upon a detailed study of the coal fields 
! herein treated, should be emphasized. 
Mr. Stanton has determined all of the Cretaceous fossils discovered, 
except a few Foraminifera, and has contributed his conclusions con- 
cerning (lie age of the beds. The Eocene fossils were determined by 
the writer. 
The general plan of the discussion followed is: (1) The general 
geology of the coal fields and adjoining areas; (2) the distribution of 
the coal and the present condition of mining; and (?>) the physical and 
chemical characters of the coal. 
Several coal-bearing areas have been recognized in the region adja- 
cent to the valley of the Rio Grande in New Mexico and Texas. 1 The 
1 Coal fields of Colorado, by R. C. Hills: Mineral Resources U. S. 1892, pp. 319 et seq. 
New Mexico, Its Resources, etc., New Mexico Bureau of Immigration, Santa Fe\ 1884. . 
The Cerillos coal field, by John J.Stevenson: Trans. New York Acad. Sci., Jan., 1890, pp. 105-122. 
Mr. T. W. Stanton has made an examination of the White Oaks mine, and informs the writer that 
he coal there is probably Laramie. 
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