Editing Big Spring, Texas (section)

=== Origin of the name "Big Spring" ===
The area's "big spring", long dry but recently modified to draw water from Comanche Trail Lake, was of major importance to all life in the surrounding area. In the early 1840s, it was the center of a territorial dispute between [[Comanche]] and [[Pawnee people|Pawnee]] tribes, and has been a major watering hole for wildlife and prehistoric people in this semiarid area.<ref name="Brune, G 1981. p. 235">Brune, G. 1981. ''Springs of Texas''. Vol. I, Fort Worth: Branch Smith, p. 235</ref> Early military scouting reports and pioneer accounts describe the water as cold, clear, and dependable; the spring pool was about {{convert|15|ft|0|abbr=on}} deep, with the overflow going only a short distance down the draw before it sank beneath the surface. The spring has mistakenly been described in other writings as being located in Sulphur Draw. It is actually located to the south, near the top of a small, rugged, unnamed draw running eastwards from the spring, and is itself a tributary to Beal's Creek, the name given to Sulphur Draw as it flows into, through, and past the city of Big Spring.

Long used by regional inhabitants, both permanent and nomadic, with a large number of locally collected artifacts testifying to its heavy occupation, the spring sat astride the several branches of the later-developed Comanche War Trail as they converged on this important water hole from beyond Texas, coming south across the Northern Plains and the [[Llano Estacado]]. From the Big Spring, the war trail continued south via three branches, one to the southeast through the western part of the Concho country; one going almost due south, heading for Castle Gap and Horsehead Crossing on the [[Pecos River]]; and one heading west to Willow Springs in the sand country southwest of present Midland, before turning south down the Pecos, all headed ultimately for [[Mexico]]. As whites began to settle the western territories, the spring continued to serve as a major watering place on the southern route of the Gold Rush Trail of the early 1850s and continued in use well beyond that time, as the cross-continental trail turned into a major road for later pioneers coming into the area.

The spring was sourced from a relatively small [[aquifer]] situated on the northern end of the [[Edwards Plateau]] and the southern end of the [[High Plains (United States)|High Plains]], being, structurally, a collecting sink of lower [[Cretaceous]] (Fredericksburg) limestones and sands.<ref name="Brune, G 1981. p. 235" /> The spring aquifer held a large quantity of water due to the great number of fractures, solution channels, and interstices in the rocks and underlying sands, although the areal extent of the Big Spring sink is estimated to be only {{convert|1|mi|0|abbr=on}} in diameter, with the main area only {{convert|3000|ft|0|abbr=on}} wide and almost circular, with some ellipticity trending towards the west. The Cretaceous beds subsided about {{convert|280|ft|0|abbr=on}} below their normal position, centered on the southeast quarter of Section 12, Block 33 T1S; T&P RR Co survey, and the entire stratum appears to be preserved within the sink, the surface topography roughly following the subsurface subsidence.<ref>{{cite book |last1=Livingston |first1=P.P. |last2=Bennett |first2=R.R. |title=Geology and ground-water resources of the Big Spring area, Texas |series=Water Supply Paper 913 |date=1944 |publisher=United States Geological Survey |page=113 }}</ref> This writing identifies the sink as one of a number of similar subsurface geologic features in the surrounding area, differing from the Big Spring sink only in the fact that the surface topography above the others, while showing some decline, does not dip low enough to intersect the top of the water tables; hence, no springs could form from the other aquifers. In a passing comment, enigmatic in its content and disappointing in its brevity, the report states no other comparable deep sinks formed elsewhere on the Edwards Plateau.

The same publication suggests the spring's discharge volume was in excess of {{convert|100000|gal|liter|0}} per day at the time of the railroad's arrival in the area in the late 1880s. The water was heavily mined by wells built by both the railroad and the early town of Big Spring, greatly in excess of its modest recharge rate, until the water table first dropped below the level of the spring outlet, and finally, was completely depleted by the mid-1920s. The city now artificially fills the spring from its current source of water as a means of allowing residents and visitors to maintain some idea of how it appeared in times past.