lxxii REPORT OF THE STATE GEOLOGIST. 



Each of these has its definite relations to the chances for artesian 

 water supply. In the Gulf Slope, which embraces what has been 

 called the Gulf Border Formations, we have four artesian water belts, 

 or sources of artesian supply, viz: The Trinity Sands, the Lower 

 Cross-Timber Sands, the Fayette Beds, and the Carrizo Sandstone on 

 the Kio Grande border. The Trinity Sands will furnish artesian water 

 to all that country between their eastern border and the Basal Clays 

 of the Tertiary (if no more), provided the topographic features are 

 favorable, which is the case over the greater part of the area. This 

 water is only partly mineralized, and by proper casing it seems possi- 

 ble to secure water well suited for ordinary uses. The depths at which 

 it is reached vary from 100 to 2000 feet, which is the deepest bore of 

 which we have any record. 



The area in which water will be furnished by the Lower Cross- 

 Timber Sands is much more limited and local, but its extent is gov- 

 erned by the same principles as the other. 



The Fayette Beds will furnish water to the entire coast country. 

 Owing to the amount of pyrites and other mineral matter they contain 

 the water will be more or less mineralized wherever the bore is any 

 great distance from the outcrop of the beds, while near the outcrop the 

 water secured from them is found free from minerals. 



The Carrizo Sandstone will doubtless supply water to much of the 

 Nueces and Rio Grande valley below Eagle Pass. Wells have already 

 been bored to strike all these beds, and there is no longer any doubt as 

 to their availability. 



In the Central Basin both the topography and character of the 

 rock material seem to favor the finding of artesian water in many 

 localities. Natural artesian water occurs in the many springs found 

 from Lampasas westward, and numerous wells have secured flowing 

 water, both in the eastern border of the basin and at and beyond the 

 Pecos. In this division there are two areas of possible catchment ba- 

 sins which may serve as a source of supply for artesian wells. The 

 first of these is the Richland sandstones, which are slightly topograph- 

 ically higher than a portion of the country they underlie to the north. 

 This is also the case with the southern border of some of the Brown- 

 wood beds. Therefore, in some places in the Colorado Coal Field arte- 

 sian water will be found ; but not fresh water. In common with most 

 waters found in this basin it will be saline, as is clearly proven by 

 such wells as are already flowing. The amount of salt contained in 



