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Structure, Stratigraphy, and Hydrogeology of the Northern Roswell Artesian Basin, Chaves County, New Mexico

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Structure, Stratigraphy, and Hydrogeology of the Northern Roswell Artesian Basin, Chaves County, New Mexico CIRCULAR 93 Structure, Stratigraphy, and Hydrogeology of the Northern Roswell Artesian Basin, Chaves County, New Mexico by KAY C. HAVENOR, CPG 1968 STATE BUREAU OF MINES AND MINERAL RESOURCES NEW MEXICO INSTITUTE OF MINING AND TECHNOLOGY CAMPUS STATION SOCORRO, NEW MEXICO NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY Stirling A. Colgate, President STATE BUREAU OF MINES AND MINERAL RESOURCES Frank E. Kottlowski, Acting Director THE REGENTS MEMBERS Ex OFFICIO: THE HONORABLE DAVID F. CARGO .............. Governor of New Mexico LEONARD DELAYO ............................ Superintendent of Public Instruction APPOINTED MEMBERS: WILLIAM G. ABBOTT ........................................................................ Hobbs EUGENE L. COULSON, M D ............................................................ Socorro THOMAS M. CRAMER ................................................................... Carlsbad STEVE S. TORRES, JR. ..................................................................... Socorro RICHARD M. ZIMMERLY ............................................................... Socorro For sale by the New Mexico Bureau of Mines & Mineral Resources Campus Station, Socorro, New Mexico 87801—Price $2.00 Abstract Structural and stratigraphic controls of the quantity Andres of the Northwest Shelf of southeast New Mexico and quality of waters within the northernmost part of the and west Texas. Roswell artesian basin were studied using outcrops, Reduced head, because of regional over-appropriation, cores, samples, and electric logs. and reduced pressure, caused by locally intensive pumping Three structural zones are recognized: The Border on the Roswell block, relieve the retarding hydrostatic Hill, Six Mile, and YO. A fourth near the town of Dex- pressure on the saline waters in the regionally porous ter is suggested, and a fifth in the vicinity of T. 14 S., R. Slaughter zone and permit saline water encroachment into 27 E. is considered because of the close dating of fault- the Roswell block. The positioning of the Queen aquitard ing (early Desmoines). Three structural blocks, Six on the downthrown side of the YO structural zone probably Mile, Roswell, and Orchard Park, between the first four inhibits the movement of saline water from the Roswell to of these zones are delineated. the Orchard Park block. The strata in the Orchard Park block are most uni- Erosion of the Roswell block has developed a collapse form and compare generally to the complete section breccia and overlying terra rossalike residual clay, preserved in the subsurface east of the artesian basin. heretofore referred to the Artesia Group. This younger The Glorieta, lower and upper units of the San Andres, deposit forms the aquitard on the Roswell block. Physical and most of the Artesia Group are present. The artesian differences of the Queen aquitard indicate that its leakage aquifer is developed in the top one third of the San factor will be much higher than the Queen. Andres (all in the upper unit) and in the overlying The Six Mile block is a grabenlike tilted fault block. A Grayburg. The Queen forms the aquitard between the more complete San Andres comprises part of this block artesian and shallow aquifers. The latter comprises part than the Roswell block. Remnants of the Artesia, of the Seven Rivers Formation and the overlying previously reported, are not present in part of the block. Tertiary–Quaternary alluvium. Considerations for control of saline encroachment Structural uplift and consequent deep, irregular ero- include additional stratigraphic work to determine the areal sion have stripped the Artesia Group and the upper unit extent of the base of the aquifer porosity and Slaughter of the San Andres from the Roswell block. Secondary porosity interface. Retardation might result from the porosity enlargement has been developed in the employment of injection wells. Further investigations Slaughter zone of the lower San Andres and constitutes should include acquiring more electric logs, sample the principal porosity zone of the artesian aquifer. The examination, continued study of the Glorieta, and Slaughter zone, a regionally porous and permeable unit, adaptation of hydrologic methods to the geology. is the principal hydrocarbon-producing zone of the San 1 Introduction The exact limits of the Roswell artesian basin have not INVESTIGATIONS been hydrologically delineated. As administratively defined by the State Engineer, the Roswell artesian basin, in Investigators have published hydrogeologic work on the western Chaves and Eddy counties, New Mexico, has an Roswell artesian basin since the beginning of the century, irregular shape and extends from the state line southwest of most notably the reports by Fieldler and Nye (1933) and Carlsbad to about 15 miles north of Roswell. The eastern Mourant (1963). edge of the declared basin lies immediately east of the Most of the many other reports on the area are local or Pecos River and its westernmost margin is the Chaves limited in scope. Since 1933 (excepting Mourant), the rocks county line. that carry and contain the waters of the Roswell artesian The hydrologic complex comprising the basin is es- basin have received little attention. A selected bibliography sentially the crest of the Sacramento Mountains. The follows the References at the end of this report. complimentary hydrologic complex resulting in the artesian The State Engineer's Office, the U.S. Geological Survey, basin near the Pecos Valley covers more than 3000 square the Roswell Geological Society, and various individuals are miles. For practical purposes, the southern limit of the presently conducting geological and hydrological basin system is in the immediate vicinity of Major Johnson investigations. The New Mexico Institute of Mining and Springs, north of Carlsbad. The northern ground-water Technology, in conjunction with the New Mexico Water boundary is near Arroyo Macho, north of Roswell. Resources Institute, has commenced a study of the Pecos This investigation primarily concerns the vicinity of the Valley and the Roswell artesian basin system. City of Roswell in the northernmost part of the Roswell artesian basin. The effective extent of the area considered ACKNOWLEDGMENTS does not go beyond the limits of western Chaves County. I am indebted to many individuals and organizations for The structure contouring (pls. 1 and 2) covers a larger area the data used and the assistance received in arriving at the than that considered in dealing with the more detailed interpretations presented herein. stratigraphy of the producing formations. The City of Roswell, the Pecos Valley Artesian Con- PURPOSE servancy District, and the Hagerman Irrigation Company each expended many thousands of dollars to drill the test For sixty years, the Roswell artesian basin has been the holes required to obtain the data used in this report. I almost continuous subject of various hydrologic and cannot fully express my appreciation for the opportunity to geologic investigations. Fiedler and Nye's (1933) report on use this information. The constituents and members of the area culminated a most complete geologic investigation. these groups should be proud of the councilmen and directors who have intelligently, aggressively, and During the thirty years following their report, new prudently sought practical and scientifically sound geological and hydrological techniques have provided solutions to large water problems, while constantly keeping much additional information. in mind the well-being and rights of all other water users. This investigation generally attempts to re-evaluate the I thank my coworkers on the Stratigraphic Studies structural and stratigraphic geology of the northern part of Committee of the Roswell Geological Society. In con- the Roswell artesian basin, to analyze the abundant junction with the U.S. Geological Survey, these com- hydrologic data available in the light of these geological mitteemen built a correlation network throughout the entire controls, and to explain local conditions in various areas of Roswell artesian basin. This work (in preparation) the northernmost part of the basin. Specifically, this paper represents the first major regional geological reevaluation considers the stratigraphic and/or structural controls that of the basin since Fiedler and Nye. I have freely used these influence the movement of ground water and control the regional control data and have attempted to utilize, for the quantity, quality, and distribution of saline water in the sake of conformity, the same formational tops chosen by the Roswell Geological Society, which provide essentially immediate Roswell area. the upper and lower boundaries for the stratigraphic The writer hopes to propagate the criticism and dispute discussions of this report; however, I accept all necessary to stimulate additional investigations and provide responsibility for the interpretations presented herein, as more alert investigators with a different approach to an old well as for formation tops indicated (or possibly omitted). problem. If nothing else, this investigation may give some My sincere gratitude goes to the following fellow insight into the specific structural, stratigraphic, and scientists for the individual help and constructive criticism hydrogeologic problems that need re-examining. they offered me: Jack R. Barnes, consulting hy- 2 drologist; S. E. Galloway, State Engineer's Office; Mervin by terms of the agreement with Texas, designated for L. Klug, ground-water consultant;
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