Mapping the Altitude of the Top of the Dockum Group and Paleochannel Analysis Using Surface Geophysical Methods On and Near Cannon Air Force Base in Curry County, New Mexico, 2020

Scientific Investigations Report 2022-5050
Prepared in cooperation with the Air Force Civil Engineer Center
By: , and 

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Abstract

The hydrogeology on and near Cannon Air Force Base (AFB) in eastern New Mexico was assessed to gain a better understanding of preferential groundwater flow paths through paleochannels. In and near the study area, paleochannels incised the top surface of the Dockum Group (Chinle Formation) and were subsequently filled in with electrically resistive coarse-grained sediments of the overlying Ogallala Formation, resulting in a preferential groundwater flow path in the form of a paleochannel network. A better understanding of the spatial characteristics of this preferential groundwater flow path is needed to support ongoing efforts to remediate groundwater contamination at Cannon AFB. Therefore, the U.S. Geological Survey, in cooperation with the U.S. Air Force Civil Engineer Center, used surface geophysical resistivity methods and data compiled from previous studies to better understand the spatial distribution and characteristics of the paleochannel network incised into the top of the Dockum Group.

Previous studies have shown these paleochannels incised into the top of the Dockum Group with increasing resolution, but limited borehole data on and near Cannon AFB continued to make accurately mapping the top of Dockum Group challenging. For this study, surface geophysical resistivity measurements in the form of time-domain electromagnetic soundings made by the U.S. Geological Survey were used in conjunction with data previously published by Architecture, Engineering, Construction, Operations, and Management and borehole data compiled from the New Mexico Water Rights Reporting System database to prepare an updated map of the top of the Dockum Group that includes the location and characteristics of paleochannels incised into the top of the Dockum Group (Chinle Formation). A total of 149 borehole picks (determinations of the tops and bases of geologic units and their hydrogeologic-unit equivalents) were obtained from previous studies, along with 72 additional borehole picks from the New Mexico Water Rights Reporting System database and 43 picks from newly collected time-domain electromagnetic soundings. The data were gridded and contoured using Oasis Montaj v. 9.8.1.

The updated map of the top of Dockum Group has many areas of uncertainty greater than 20 feet, because there are not enough data for the gridding process to reliably determine a value. However, this interpretation of the altitude of the top of the Dockum Group represents a substantial improvement in data resolution compared to previous studies.

Two methodologies were used to evaluate paleochannels incised in the top of the Dockum Group across the study area: (1) trend-removal grid analysis and (2) analysis with Esri’s ArcMap Hydrology toolset. These two paleochannel analysis techniques show groundwater flow direction as well as areas having the deepest saturated thickness. Hydrologically, these techniques show where aquifer storage is highest (in the deepest parts of the paleochannel network), as well as the spatial distribution of preferential groundwater flow paths (the paleochannels). The analyses indicate a large paleochannel trending to the southeast, with smaller channels feeding in from the west. Areas where groundwater management could be more beneficial are indicated by locations where these flow lines intersect the deeper parts of the paleochannel.

Introduction

The hydrogeology on and near Cannon Air Force Base (AFB) in Curry County, New Mexico, was assessed to better understand preferential groundwater flow paths in the form of paleochannels. During the Triassic, streams cut channels into the geologic unit that formed the land surface at that time; remnants of these ancient streams remain in the form of paleochannels. On and near the study area, paleochannels incised the top surface of the Triassic-age Chinle Formation of Dockum Group and were subsequently filled with electrically resistive coarse-grained sediments from the overlying Tertiary-age Ogallala Formation (Rawlings, 2016), resulting in a preferential groundwater flow path in the form of a paleochannel network. A better understanding of the spatial characteristics of this preferential groundwater flow path is needed to support ongoing efforts to remediate groundwater contamination at Cannon AFB. Chandra and others (2020, p. 1) explain “paleochannels typically act as pathways for groundwater movement and provide a potential source of groundwater. Their presence can be helpful in identifying areas suitable for recharge and at times in mitigating contamination problems in afflicted regions. Thus, mapping of paleochannels is significant in the planning and management of groundwater resources.” Therefore, the U.S. Geological Survey (USGS), in cooperation with the U.S. Air Force Civil Engineer Center, used surface geophysical resistivity methods and data compiled from previous studies to better understand the spatial distribution and characteristics of the paleochannel network incised into the top of the Dockum Group.

Purpose and Scope

The primary purpose of this report is to update previously published depictions of the paleochannel network that traverses the top of Chinle Formation of the Dockum Group on and near Cannon AFB in Curry County, N. Mex. and functions as a preferential groundwater flow path. The altitude of the top of the Dockum Group was mapped, and spatial characteristics of the paleochannel network were described by using compiled and newly collected geophysical data.

Description of Study Area

The study area consists of about 35,000 acres on and near Cannon AFB in eastern New Mexico. Cannon AFB is approximately 7 miles southwest of Clovis, N. Mex., in the Southern High Plains physiographic province (Fenneman and Johnson, 1946; Langman and others, 2004). Cannon AFB is surrounded mostly by agricultural lands and dairy farms. The mean annual precipitation in Clovis during 1981–2020 was about 18 inches, and daily mean temperatures ranged from 78 degrees Fahrenheit in July to 39 degrees Fahrenheit in January (U.S. Climate Data, 2021). Mean annual evaporation rates in this semiarid region far exceed mean annual precipitation (Tuan and others, 1969; Robson and Banta, 1995). Cannon AFB covers approximately 3,800 acres and is host to the 27th Special Operations Group of the United States Air Force (Cannon Air Force Base, 2022) (fig. 1). Because of groundwater contamination related to historical operations at the site, an environmental restoration program is ongoing (Langman and others, 2004, 2006). Environmental restoration processes at Cannon AFB are being overseen by the Department of Defense (U.S. Government Accountability Office, 2021).

Figure 1. Map of all borehole and time-domain electromagnetic sounding locations at
                        and near Cannon Air Force Base.
Figure 1.

Locations of all boreholes and time-domain electromagnetic (TDEM) soundings on and near Cannon Air Force Base in Curry County, New Mexico, 2020.

Geologic and Hydrogeologic Setting

The High Plains aquifer system is the largest aquifer in the United States and is commonly divided into three parts: the Northern High Plains aquifer, Central High Plains aquifer, and Southern High Plains aquifer (fig. 1) (Becker and others, 2002). The Southern High Plains aquifer underlies the study area. The High Plains aquifer system is commonly referred to as the “Ogallala aquifer” because the Ogallala Formation is the predominant water-bearing unit of this aquifer system (Gutentag and others, 1984).

Because the focus is on the hydrology of the area, geologic units are discussed from land surface downward (youngest to oldest), and aquifers and the geologic units that contain them are discussed together. The Quaternary-age Blackwater Draw Formation consists mostly of eolian sand deposits and overlies the Tertiary-age Ogallala Formation in the area; the Blackwater Draw Formation ranges in thickness from about 0 to 80 ft in eastern New Mexico (fig. 2; McLemore, 2001). The Blackwater Draw Formation is not considered a viable source of water in the study area. The Ogallala Formation consists of eolian sand and silt and fluvial and lacustrine sand, silt, clay, and gravel (McLemore, 2001), and ranges in thickness from about 30 to 600 ft in eastern New Mexico and western Texas (Gustavson, 1996). The Southern High Plains aquifer is the primary source of water for agriculture and public supply in the area and is primarily contained in the Ogallala Formation in eastern New Mexico (McLemore, 2001). The Ogallala Formation lies unconformably atop the upper unit of the eastward-dipping Triassic-age Chinle Formation of the Dockum Group (Dutton and Simpkins, 1986; Lucas and others, 1987). The Southern High Plains aquifer is underlain in most of the area by relatively impermeable rocks equivalent to the Chinle Formation (Cronin, 1969; Gutentag and others, 1984). The rocks that compose the Chinle Formation consist mostly of clay with some intermixed shale and silt that serve as barriers to groundwater movement (Cronin, 1969). The Chinle Formation ranges in thickness from about 0 to 400 feet (ft) in eastern New Mexico (McGowen and others, 1977). Locally, the Chinle Formation is referred to as the “red beds,” an informal name commonly used for sedimentary rocks rich in ferric oxides (Neuendorf and others, 2005). The Triassic-age Santa Rosa Formation underlies the Chinle Formation. The Chinle Formation and the Santa Rosa Formation are the only members of the Dockum Group present in the study area. In addition to the Ogallala Formation, the Santa Rosa Formation is the other water-bearing member of the High Plains aquifer system present in the study area; the sandstone and shale aquifer is contained in the Santa Rosa Formation of the Dockum Group (Gustavson and Holliday, 1985) and is as a minor source of water, mostly for agricultural uses (New Mexico Interstate Stream Commission and New Mexico Office of the State Engineer, 2016). Although in New Mexico the water-bearing unit of the Dockum Group in the study area (the Santa Rosa Formation) is known as the sandstone and shale aquifer, the water-bearing unit of the Dockum Group is known as the Dockum aquifer in Texas (Matherne and Stewart, 2012; New Mexico Interstate Stream Commission and New Mexico Office of the State Engineer, 2016).

Figure 2. Geology chart of near-surface geologic units and their hydrogeologic‐unit
                        equivalents on and near Cannon Air Force Base.
Figure 2.

Geology of the near-surface (top) geologic units and their hydrogeologic‐unit equivalents on and near Cannon Air Force Base, Curry County, New Mexico (modified from Matherne and Stewart, 2012).

The hydrogeologic setting on and near Cannon AFB is the complex result of the Laramide orogeny between 80 and 55 million years ago that formed the Rocky Mountains and possibly earlier orogenies as well that predate the Laramide orogeny (Gustavson and Holliday, 1985). Prior to the Laramide orogeny, eastern New Mexico and the Texas Panhandle were covered by a large sea that was part of the Western Interior Seaway, which deposited the Dockum Group sediments during the Triassic period (Gustavson and Holliday, 1985). The Dockum Group is composed of sandstone with interbedded shales grading upward to a shaly sandstone or siltstone and clay (Luckey and Becker, 1999). When the Laramide orogeny began and the Western Interior Seaway regressed, the area on and near the present-day Cannon AFB was traversed by large rivers that had their headwaters in the Rocky Mountains and predominately flowed in an east-southeast direction. These rivers downcut into the Chinle Formation that forms the upper part of the Dockum Group until the late Miocene epoch (Gustavson and Holliday, 1985) when the incised channels began to fill with fluvial sediments such as sand and gravel originating from the Rocky Mountain headwaters; subsequent to channel incision and streambed sediment deposition, sand and gravel deposits from complex ancestral alluvial fan systems were deposited and then reworked to form the overlying Ogallala Formation (Knowles and others, 1984).

Previous Studies

The USGS has conducted several assessments in recent years to characterize the hydrogeology on and near Cannon AFB. Data and information from previous studies were used to guide the assessment described herein. Previous USGS studies include Collison (2016), Langman and others (2006), and Langman and others (2004). A previous study by Architecture, Engineering, Construction, Operations, and Management (AECOM, 2020) assessed the location of the paleochannels on and near Cannon AFB by using available borehole data from the New Mexico Water Rights Reporting System (NMWRRS) database and the Cannon AFB Installation Restoration Program. In 2018, the USGS collected geophysical logs from 21 existing boreholes and from 4 new boreholes at the Cannon AFB as well as 4 new test wells (available through the USGS GeoLog Locator system at https://doi.org/10.5066/F7X63KT0). Those data were incorporated in this report and were also used in AECOM (2020), which describes the spatial distribution paleochannels at Cannon AFB by using available borehole data. AECOM (2020) discusses limitations of their final map resulting from gaps in the borehole data that they used in their analysis. The data used to develop their interpretation of the spatial distribution of paleochannels in the top of the Dockum Group are among the data incorporated in the development of the updated interpretation of the spatial distribution of paleochannels in top of Dockum Group described in this report.

Data Collection, Compilation, and Processing Methods

Resistivity measurements are commonly used to interpolate geologic and hydrogeologic properties between borehole locations or in areas where no borehole data exist. Data from surface geophysical resistivity methods were used to fill data gaps pertaining to the spatial distribution of paleochannels at Cannon AFB. Surface geophysical resistivity measurements in the form of time-domain electromagnetic (TDEM) soundings made by the USGS were published as a companion data release to this report (Payne and Teeple, 2020). These TDEM soundings were used in conjunction with data published in AECOM (2020) and borehole data compiled from NMWRRS (2021) to prepare an updated map of the top of the Dockum Group that includes the location and characteristics of paleochannels incised into the top of the Dockum Group (Chinle Formation).

TDEM Soundings

TDEM instruments measure the bulk resistivity of the subsurface by producing an alternating electrical current in a transmitter loop of wire deployed on the land surface (Vignesh and others, 2015). TDEM soundings in this study were collected using the Geonics Protem 47 and 57 systems, respectively (Geonics Limited, 2006). Both systems use a multiturn receiver coil to measure electromagnetic (EM) fields in the center of the transmitter loop. The TDEM soundings were collected at two frequencies using the Geonics Protem 47 (285 and 75 hertz [Hz]) and three frequencies using the Geonics Protem 57 (30, 7.5, and 3.0 Hz) for a total of five frequencies. The lower frequencies penetrate deeper into the subsurface. For each frequency, 10 stacks (independent measurements) were collected by using an integration time of either 8 or 15 seconds, the latter of which was used for collecting 3.0-Hz data with the Geonics Protem 57. Longer integration time helps improve signal to noise ratio, thereby compensating for the dissipation of the transmitted signal at depth and for the greater potential for EM background noise with these soundings compared to soundings collected at higher frequencies (shallower depths). Additional information about the TDEM method and data collected in this study are available in Payne and Teeple (2020). The TDEM data were collected in accordance with methods defined by the American Society of Testing and Materials (1999). Comprehensive descriptions of the theory and application of geophysical resistivity methods, as well as tables of the electrical properties of earth materials, are presented in Keller and Frischknecht (1966) and Lucius and others (2007) and will not be detailed in this report.

Sixty TDEM soundings, 43 of which were used in the final interpretation, were collected at Cannon AFB (fig. 1) to supplement existing borehole data. TDEM transmitter loops covering 100 square meters were used to ensure that the depth of exploration would accurately image the electrically conductive Chinle Formation. For each TDEM sounding, the voltages measured from the eddy currents were averaged and evaluated statistically by using preprocessing scripts that incorporate raw field data (namely, voltage data) and independently compute the uncertainty of each time gate. A time gate is defined as one of multiple time windows (after current shutoff) during which discrete voltages are measured. Variability observed in a time gate can represent signal noise or a systematic change not representative of stable data (Mandache and Brothers, 2005).

In this application, 10 percent of the data from each tail of the distribution were removed, and an average of the remaining 80 percent was computed. The resulting averages were then compared to a noise sample collected at the sounding location, and any values that were less than half of the associated EM background noise value were removed from the final sounding. The final averaged values for each time gate were saved as processed data files and used for inverse modeling whereby the spatial distribution of subsurface resistivity was estimated from the measured voltage. The IX1D v3 program, developed by Interpex Limited (1996), was used for inverse modeling of the TDEM soundings. A smooth inverse model—defined as a multilayered model that holds the depth values fixed and allows the resistivity values to vary during inversion—was fit to the data by using Occam’s inversion principle (Constable and others, 1987). Layered-earth models, which are simplified models used to represent hydrogeologic units, were then generated and fit to the data to better represent the electrical stratigraphy of each sounding. The changes in resistivity from the inverse modeling results of the final processed TDEM data were used to determine changes in hydrogeologic contacts, namely the tops and bases of hydrogeologic units. More detailed descriptions of the field procedures, equipment setup, and processing steps used to develop one-dimensional soundings (commonly referred to as “virtual borehole resistivity logs”) from the TDEM soundings are available in the data release that accompanies this report (Payne and Teeple, 2020).

Each of the 60 soundings was evaluated for accuracy by first looking at the background EM noise in the location of the sounding. This evaluation led to the removal of eight soundings from the dataset because the noise level overwhelmed any measurable signal. The remaining soundings were then carefully analyzed and compared to nearby borehole data. This additional scrutiny and comparison to nearby borehole data led to the removal of nine additional soundings from the dataset. For all removed soundings, the depth to top of the Dockum Group differed from the depth in nearby boreholes by more than 10 ft; this large difference in depth helped to confirm the decision to remove these soundings from the dataset was the correct decision. All TDEM sounding locations are listed in table 1; the TDEM soundings that were used in the analysis include depth and altitude values for the top of the Dockum Group.

Table 1.    

Location, depth to top of Dockum Group, and altitude of the top of Dockum Group for the time-domain electromagnetic (TDEM) soundings used in the final interpretation (Payne and Teeple, 2020).

[ID, identifier; WGS 84, World Geodetic System 1984; --, data not available because sounding was not used in final interpretation]

Site ID Longitude,
WGS 84 datum
(decimal degrees)
Latitude,
WGS 84 datum
(decimal degrees)
Land surface altitude
(feet)
Depth to top of Dockum Group
(feet)
Top of Dockum Group altitude
(feet)
TDEM01 −103.30483 34.38232 4,276 403 3,873
TDEM02 −103.30527 34.37405 4,268 398 3,870
TDEM03 −103.30437 34.38837 4,274 -- --
TDEM04 −103.30412 34.38720 4,285 359 3,926
TDEM05 −103.30393 34.38623 4,285 -- --
TDEM06 −103.30355 34.38498 4,275 -- --
TDEM07 −103.30330 34.38407 4,275 336 3,939
TDEM08 −103.30312 34.38323 4,275 356 3,919
TDEM09 −103.30317 34.38223 4,274 357 3,917
TDEM10 −103.30323 34.38130 4,274 346 3,928
TDEM11 −103.30328 34.38037 4,274 360 3,914
TDEM12 −103.30338 34.37935 4,273 365 3,908
TDEM13 −103.30337 34.37832 4,272 355 3,917
TDEM14 −103.30752 34.36790 4,264 392 3,872
TDEM15 −103.30932 34.37123 4,265 389 3,876
TDEM16 −103.30658 34.36967 4,266 -- --
TDEM17 −103.30535 34.36790 4,266 -- --
TDEM18 −103.33008 34.38073 4,279 -- --
TDEM19 −103.32565 34.37727 4,268 361 3,907
TDEM20 −103.32267 34.37452 4,268 365 3,903
TDEM21 −103.32165 34.37387 4,269 362 3,907
TDEM22 −103.32033 34.37225 4,270 373 3,897
TDEM23 −103.31735 34.36915 4,267 403 3,864
TDEM24 −103.31477 34.36758 4,266 -- --
TDEM25 −103.32442 34.38033 4,277 348 3,929
TDEM26 −103.32348 34.37972 4,275 339 3,936
TDEM27 −103.32260 34.37910 4,274 348 3,926
TDEM28 −103.32032 34.37632 4,270 337 3,933
TDEM29 −103.31932 34.37563 4,271 338 3,933
TDEM30 −103.31780 34.37453 4,270 351 3,919
TDEM31 −103.31748 34.36793 4,268 396 3,872
TDEM32 −103.29897 34.40162 4,310 -- --
TDEM33 −103.30053 34.39972 4,311 372 3,939
TDEM34 −103.29925 34.39788 4,305 362 3,943
TDEM35 −103.29735 34.38978 4,279 -- --
TDEM36 −103.29650 34.38875 4,273 -- --
TDEM37 −103.29645 34.38537 4,266 -- --
TDEM38 −103.30858 34.38367 4,275 394 3,881
TDEM39 −103.30357 34.37487 4,270 371 3,899
TDEM40 −103.31690 34.38690 4,285 -- --
TDEM41 −103.31383 34.38858 4,284 -- --
TDEM42 −103.31217 34.38967 4,286 -- --
TDEM43 −103.30780 34.39427 4,288 411 3,877
TDEM44 −103.30710 34.39497 4,291 427 3,864
TDEM45 −103.30667 34.39598 4,293 407 3,886
TDEM46 −103.30390 34.39632 4,297 385 3,912
TDEM47 −103.30312 34.38272 4,274 359 3,915
TDEM48 −103.30323 34.38175 4,274 354 3,920
TDEM49 −103.30333 34.38080 4,274 369 3,905
TDEM50 −103.30345 34.37983 4,274 373 3,901
TDEM51 −103.30342 34.37877 4,272 363 3,909
TDEM52 −103.31287 34.38687 4,281 -- --
TDEM53 −103.30510 34.37145 4,271 -- --
TDEM54 −103.30585 34.37720 4,269 422 3,847
TDEM55 −103.30593 34.37850 4,270 431 3,839
TDEM56 −103.30628 34.37968 4,274 439 3,835
TDEM57 −103.30645 34.38057 4,273 426 3,847
TDEM58 −103.30610 34.38157 4,272 420 3,852
TDEM59 −103.30607 34.38252 4,273 412 3,861
TDEM60 −103.30585 34.38595 4,285 -- --

Data Compilation

Table 2 lists the altitude of the top of the Dockum Group as interpreted from all boreholes in the study area. (All of the data in table 2 are from AECOM, 2020.) AECOM (2020) computed the top of Dockum Group altitude (shown in table 2) by subtracting the depth to the top of the Chinle Formation from a 1-meter (m) digital elevation model (U.S. Geological Survey, 2017). Because of the possible discrepancies between surface altitudes used by AECOM and those used in this report, actual altitudes of the top of the Dockum Group may differ slightly.

Table 2.    

Location, depth to top of Dockum Group, and altitude of the top of Dockum Group from Architecture, Engineering, Construction, Operations, and Management (AECOM, 2020).

[ID, identifier; WGS 84, World Geodetic System 1984]

Site ID Longitude,
WGS 84 datum
(decimal degrees)
Latitude,
WGS 84 datum
(decimal degrees)
Land surface altitude
(feet)
Depth to top of Dockum Group
(feet)
Top of Dockum Group altitude
(feet)
CC1050 −103.26334 34.40376 4,319 400 3,919
CC1542 −103.25902 34.36931 4,238 350 3,888
CC364S −103.27215 34.36207 4,258 375 3,883
CC403POD8 −103.29185 34.35303 4,258 400 3,858
MW-A −103.30873 34.37191 4,267 339 3,928
MW-M −103.30280 34.36665 4,264 287 3,978
MW-F −103.30398 34.38925 4,278 368 3,910
CC2191POD1 −103.31466 34.40888 4,330 354 3,976
CC1264 −103.25898 34.37474 4,244 302 3,942
MW-D −103.30679 34.36587 4,265 355 3,910
MW-H −103.30484 34.38548 4,279 348 3,931
MW-Fa −103.30453 34.36572 4,266 350 3,916
CC01574 −103.31150 34.41104 4,324 405 3,919
CC873 −103.31008 34.40777 4,327 335 3,992
CC142S −103.26117 34.34574 4,227 346 3,881
CC02191POD1 −103.31324 34.40915 4,330 354 3,976
BH-3 −103.30351 34.38133 4,274 378 3,896
PW-12 −103.31363 34.40040 4,311 404 3,907
PW-8 −103.32017 34.40406 4,321 415 3,906
PW-6 −103.32590 34.37293 4,269 360 3,909
CC293POD7 −103.26775 34.34935 4,242 430 3,812
CC164 −103.29908 34.35874 4,264 407 3,857
CC1315 −103.30286 34.34575 4,242 362 3,880
CC1868 −103.26774 34.36024 4,259 402 3,857
MW-Pa −103.30229 34.38625 4,274 360 3,914
PW-5 −103.30247 34.39425 4,294 385 3,909
CC1320S −103.25681 34.35483 4,246 410 3,836
CC142S2 −103.25903 34.34029 4,211 397 3,814
CC00451S6 −103.35992 34.41849 4,366 432 3,934
CC303S2 −103.28312 34.34398 4,241 360 3,881
MW-Ga −103.30401 34.38920 4,279 360 3,919
BH-4 −103.30327 34.37441 4,270 393 3,877
CC1857 −103.29223 34.40399 4,306 348 3,958
OW-1 −103.32138 34.40217 4,318 414 3,904
CC1610 −103.26551 34.40379 4,318 378 3,940
CC1761 −103.26773 34.36750 4,255 341 3,914
CC02095POD1 −103.26773 34.38041 4,243 330 3,913
CC1499 −103.26554 34.37478 4,245 322 3,923
CC114S3 −103.36433 34.42214 4,376 437 3,939
CC122S −103.33242 34.41603 4,347 438 3,909
PW-4a −103.32123 34.40246 4,321 416 3,905
CC01476POD4 −103.28306 34.36210 4,260 370 3,890
CC1476POD4 −103.28306 34.36210 4,260 370 3,890
CC317S −103.35332 34.42031 4,369 452 3,917
CC563 −103.28360 34.40963 4,330 388 3,942
CC2056POD6 −103.34506 34.41143 4,324 382 3,942
CC1182 −103.26223 34.37203 4,241 320 3,921
GTW-2 −103.29610 34.38433 4,270 365 3,905
CC1901 −103.35499 34.38305 4,297 348 3,949
CC1190 −103.34557 34.38919 4,309 365 3,944
CC1069 −103.28340 34.40590 4,322 373 3,949
CC122POD8 −103.33687 34.41462 4,345 423 3,922
CC1995 −103.29075 34.40431 4,308 350 3,958
CC1105POD7 −103.33130 34.34400 4,230 248 3,982
CC2235POD1 −103.33575 34.37897 4,279 335 3,944
MW-G −103.30332 34.38687 4,279 358 3,921
CC142S3 −103.28896 34.36507 4,260 370 3,890
CC971 −103.35719 34.39089 4,320 360 3,960
CC1326 −103.26115 34.37477 4,246 321 3,925
PW-3 −103.31455 34.39882 4,306 400 3,906
CC02386 −103.33780 34.42036 4,357 435 3,922
BH-2 −103.31086 34.37953 4,273 391 3,882
CC119S4 −103.26300 34.43422 4,353 406 3,947
CC366S6 −103.25677 34.34574 4,222 394 3,828
MW-Sa −103.30280 34.36606 4,263 362 3,901
CC1538 −103.26338 34.39109 4,283 345 3,938
GTW-3 −103.31476 34.40281 4,318 389 3,929
CC142S4 −103.29441 34.36759 4,261 363 3,898
CC02093POD1 −103.28025 34.38013 4,252 328 3,924
MW-Na −103.29628 34.38836 4,269 355 3,914
CC00145S4 −103.29403 34.36751 4,261 363 3,898
PW-4 −103.32097 34.40095 4,311 400 3,911
CC1032POD7 −103.34000 34.38527 4,299 349 3,950
CC00145S3 −103.28742 34.36391 4,260 370 3,890
PW-2 −103.32893 34.40455 4,307 375 3,932
CC875 −103.30166 34.40449 4,316 342 3,974
MW-W −103.29739 34.38343 4,273 364 3,909
CC1551 −103.29583 34.42805 4,362 395 3,967
CC02094POD1 −103.26772 34.38374 4,261 333 3,928
CC933 −103.35320 34.35853 4,279 273 4,006
CC303POD3 −103.27762 34.34487 4,244 375 3,869
GTW-1 −103.33567 34.39508 4,319 355 3,964
CC1990POD1 −103.38314 34.41997 4,382 410 3,972
CC865 −103.27765 34.40575 4,324 370 3,954
BH-1 −103.31431 34.38233 4,274 376 3,898
CC403A −103.29075 34.35575 4,260 377 3,883
CC856 −103.26557 34.37298 4,249 322 3,927
CC1339 −103.29325 34.37424 4,270 360 3,910
CC2472 −103.27141 34.43222 4,352 395 3,957
CC01864 −103.27429 34.37478 4,256 327 3,929
CC1864 −103.27429 34.37478 4,256 327 3,929
CC1516 −103.30057 34.43830 4,365 387 3,978
CC1411 −103.29619 34.43830 4,378 401 3,977
CC1072 −103.28412 34.40728 4,328 378 3,950
CC802 −103.25676 34.37477 4,246 323 3,923
CC1855 −103.25899 34.39470 4,302 360 3,942
MW-Y −103.30145 34.38361 4,273 357 3,916
CC1180S −103.35514 34.36116 4,287 276 4,011
CC142S5 −103.29416 34.36941 4,264 358 3,906
CC00875 −103.30055 34.40381 4,313 340 3,973
MW-Ta −103.30262 34.36664 4,264 361 3,903
CC792 −103.25779 34.36833 4,242 317 3,925
CC914 −103.26553 34.37115 4,250 323 3,927
CC743 −103.31705 34.35213 4,250 291 3,959
PW-9 −103.31244 34.37603 4,273 378 3,895
CC1026 −103.35318 34.36759 4,281 270 4,011
EB-1 −103.33625 34.38305 4,290 335 3,955
CC757 −103.28817 34.40460 4,314 355 3,959
CC114S8 −103.38632 34.43487 4,413 422 3,991
CC293 −103.26554 34.35300 4,251 408 3,843
CC02014POD1 −103.27038 34.37169 4,254 323 3,931
CC2014POD1 −103.27038 34.37169 4,254 323 3,931
CC2120POD1 −103.38425 34.38592 4,322 292 4,030
PW-7 −103.33037 34.39571 4,322 368 3,954
CC293S5 −103.26224 34.35025 4,241 403 3,838
CC293A −103.26119 34.35846 4,259 390 3,869
MW-V −103.33684 34.40500 4,328 370 3,958
CC00145S5 −103.29512 34.37025 4,266 358 3,908
CC112S3 −103.35984 34.41934 4,366 426 3,940
CC688 −103.32041 34.36178 4,265 302 3,963
CC1046 −103.25902 34.36931 4,238 309 3,929
CC1070 −103.29406 34.35300 4,259 371 3,888
MW-C −103.30458 34.36574 4,267 360 3,907
CC01476S −103.28085 34.36387 4,262 355 3,907
CC1476S −103.28085 34.36387 4,262 355 3,907
CC00873 −103.30600 34.40831 4,321 335 3,986
CC241S4 −103.38503 34.37942 4,322 285 4,037
CC318S5 −103.30942 34.34579 4,237 305 3,932
CC1558 −103.25461 34.39107 4,289 350 3,939
MW-V −103.33684 34.40500 4,328 369 3,959
CC00623 −103.31368 34.40382 4,321 374 3,947
CC00015POD5 −103.27222 34.38714 4,268 318 3,950
CC951 −103.25346 34.37201 4,250 324 3,926
CC1105POD5 −103.33126 34.34580 4,236 247 3,989
MW-Oa −103.29934 34.39684 4,300 364 3,936
MW-B −103.30288 34.36741 4,265 360 3,905
MW-Ca −103.30228 34.38975 4,275 350 3,925
MW-Ua −103.30275 34.36796 4,265 361 3,904
MW-X −103.32865 34.37282 4,268 335 3,933
CC280S −103.26557 34.37660 4,248 320 3,928
CC2160POD2 −103.29867 34.40413 4,308 330 3,978
CC650S −103.32678 34.36863 4,267 322 3,945
CC122S6 −103.33687 34.41949 4,356 428 3,928
MW-E −103.30729 34.39070 4,283 346 3,937
CC00122POD7 −103.33571 34.41843 4,355 428 3,927
MW-Rb −103.30331 34.38681 4,279 350 3,929
CC1266 −103.26773 34.36750 4,255 329 3,926
CC1142 −103.25896 34.40376 4,320 375 3,945
CC303S3 −103.27870 34.34578 4,245 360 3,885

To supplement the AECOM (2020) dataset, a search of the NMWRRS database revealed an additional 72 wells near Cannon AFB that included drillers’ descriptions of the depth at which the top of the Dockum Group was reached (NMWRRS, 2021). As with the AECOM data, these depths were subtracted from the regional 1-m digital elevation model to produce additional control points in the final depiction of the top of Dockum Group. The borehole data obtained from the NMWRRS database that were used in the final interpretation in this report are provided in table 3.

Table 3.    

Location, depth to top of Dockum Group, and altitude of the top of Dockum Group obtained from the New Mexico Water Rights Reporting System (NMWRRS, 2021).

[ID, identifier; WGS 84, World Geodetic System 1984]

Site ID Longitude,
WGS 84 datum (decimal degrees)
Latitude,
WGS 84 datum
(decimal degrees)
Land surface altitude
(feet)
Depth to top of Dockum Group
(feet)
Top of Dockum Group altitude
(feet)
CC01156 −103.32470 34.36752 4,267 295 3,972
L14689POD1 −103.33147 34.37863 4,278 193 4,085
CC00909POD2 −103.31334 34.38000 4,274 395 3,879
CC00164 −103.29847 34.35845 4,264 407 3,857
CC02222POD1 −103.26319 34.40253 4,316 380 3,936
CC02574POD1 −103.33652 34.41999 4,357 440 3,917
CC00122POD2 −103.33240 34.41567 4,346 438 3,908
CC00601 −103.24467 34.37927 4,232 323 3,909
CC00563 −103.28195 34.41016 4,331 388 3,943
CC01901 −103.35321 34.38212 4,294 348 3,946
CC02231POD1 −103.32153 34.40230 4,319 414 3,905
CC01743 −103.25457 34.38925 4,278 347 3,931
CC01002 −103.25130 34.37385 4,243 328 3,915
CC00317S −103.35332 34.42031 4,369 452 3,917
CC01875POD2 −103.24804 34.36207 4,236 328 3,908
CC00630 −103.23479 34.42191 4,315 403 3,912
CC01995 −103.29083 34.40416 4,308 350 3,958
CC01857 −103.29180 34.40380 4,307 348 3,959
CC01738 −103.25674 34.38928 4,277 345 3,932
CC01782 −103.25017 34.38925 4,280 350 3,930
CC01069 −103.28307 34.40563 4,322 373 3,949
CC02502POD1 −103.25150 34.38960 4,282 350 3,932
CC00650S −103.32687 34.36755 4,266 322 3,944
CC00280POD7 −103.25680 34.37659 4,249 330 3,919
CC01746 −103.24799 34.36749 4,241 330 3,911
CC01041 −103.25676 34.40561 4,326 400 3,926
CC01190 −103.34445 34.38938 4,310 365 3,945
CC00021POD3 −103.24333 34.44249 4,343 390 3,953
CC00558 −103.24464 34.43005 4,322 380 3,942
CC00280POD8 −103.25679 34.38023 4,253 336 3,917
CC00629 −103.25125 34.41376 4,325 398 3,927
CC00971 −103.35766 34.39123 4,321 360 3,961
CC00649 −103.24688 34.39199 4,280 353 3,927
CC00636 −103.23587 34.43004 4,324 390 3,934
CC00786 −103.24801 34.38022 4,250 326 3,924
CC02577POD1 −103.31842 34.35491 4,254 295 3,959
CC01105POD18 −103.33914 34.34677 4,239 242 3,997
CC00745 −103.25342 34.41554 4,327 394 3,933
CC01980POD1 −103.26667 34.37139 4,252 324 3,928
CC00757 −103.28741 34.40380 4,312 355 3,957
CC00814S −103.25167 34.43666 4,341 380 3,961
CC01772 −103.25235 34.38928 4,279 345 3,934
CC01780 −103.25235 34.38928 4,279 345 3,934
CC01783 −103.25235 34.38928 4,279 345 3,934
CC01431 −103.25024 34.36930 4,244 327 3,917
CC01452 −103.23479 34.43279 4,328 386 3,942
CC01072 −103.28303 34.40743 4,328 378 3,950
CC02142POD1 −103.25050 34.43538 4,336 376 3,960
CC00069POD2 −103.24889 34.43110 4,329 374 3,955
CC00021POD2 −103.25000 34.44250 4,349 384 3,965
CC01217 −103.24801 34.38022 4,250 324 3,926
CC00122POD8 −103.33630 34.41525 4,347 423 3,924
CC00981 −103.25020 34.37473 4,240 320 3,920
CC00112S3 −103.35984 34.41934 4,366 426 3,940
CC00112POD8 −103.36481 34.41794 4,358 402 3,956
CC01032POD6 −103.35112 34.39166 4,320 354 3,966
CC01781 −103.25017 34.38925 4,280 345 3,935
CC00950 −103.24690 34.38111 4,251 324 3,927
CC01461 −103.24804 34.36207 4,236 322 3,914
CC02530POD1 −103.26170 34.37519 4,250 320 3,930
CC00688 −103.32036 34.36209 4,265 302 3,963
CC01763 −103.25457 34.38925 4,278 340 3,938
CC02232POD1 −103.26411 34.40258 4,317 370 3,947
CC02573POD1 −103.35511 34.43111 4,384 410 3,974
CC02513 −103.32840 34.44839 4,397 387 4,010
CC02356POD1 −103.35581 34.37483 4,296 289 4,007
CC02056POD6 −103.34579 34.41228 4,330 382 3,948
CC01339 −103.30935 34.40201 4,321 360 3,961
CC00865 −103.27973 34.40830 4,328 370 3,958
CC01755 −103.25017 34.38925 4,280 340 3,940
CC02160POD2 −103.29553 34.40372 4,306 330 3,976
CC01477POD3 −103.25025 34.36204 4,239 322 3,917

Hydrogeologic Unit Interpretation

In order to determine the top of Dockum Group (Chinle Formation) (fig. 3), the tops and bases of geologic units (and their hydrogeologic-unit equivalents), hereinafter referred to as “borehole picks,” were first determined by analyzing previously published and newly collected lithologic descriptions and borehole geophysical logs. A total of 149 borehole picks were obtained from AECOM (2020), along with 72 borehole picks from NMWRRS (2021) and 43 borehole picks from newly collected TDEM soundings. The data were gridded using Oasis Montaj v. 9.8.1 (Seequent, 2020a) where a kriging method using an exponential variogram model trended to the southeast. Kriging is a geostatistical method that determines the most probable value at each grid node in a 50- by 50-m grid (about 164 ft between nodes in the x and y directions) for this study based on a statistical analysis of the entire dataset (Isaaks and Srivastava, 1989). Variance maps developed during the kriging process were used to evaluate the uncertainty in hydrogeologic unit surface grids in the planning of additional data-collection tasks. Generally, as the distance between data points became greater, the correlation between the data points decreased, and uncertainty in areas between the data points increased (Isaaks and Srivastava, 1989). Additional information on kriging is available in Isaaks and Srivastava (1989). The contour lines shown in figure 3 were created by using the quick contour method in Oasis Montaj v. 9.8.1 (Seequent, 2020a), are based on available data, and were not adjusted manually. Figure 3 depicts the updated general northwest-to-southeast orientation of the top surface of the Dockum Group (Chinle Formation) that underlies Cannon AFB. The blue-shaded areas in figure 3 correspond to the general location of the paleochannel network, and the result obtained is consistent with the results from previous studies (AECOM, 2020).

Figure 3. Map of borehole and T D E M sounding locations with interpreted top of Dockum
                     Group grid and bedrock contours.
Figure 3.

Locations of all boreholes and time-domain electromagnetic (TDEM) soundings with interpreted top of Dockum Group grid and bedrock contours depicting the top surface of the Dockum Group (Chinle Formation) on and near Cannon Air Force Base, Curry County, New Mexico, 2020.

Previous base-of-aquifer maps generated for the area have shown areas with water levels below the proposed base of the aquifer; therefore, the area should have been dry. This modified grid compares much better to water level data in the area and has no areas that do not correlate with the other datasets. The minimum saturated thickness in a well that has water level data is approximately 10 ft.

A map of the grid error (variance) derived from the kriging method was developed to depict where possible data gaps may still exist (fig. 4). The updated map of the top of Dockum Group has many areas of uncertainty greater than 20 ft (fig. 4) because there are not enough data for the gridding process to reliably determine a value. However, this interpretation of the altitude of the top of the Dockum Group represents a substantial improvement in data resolution compared to previous studies. The resolution over the entire study area improved because of the additional borehole data, and the resolution along the large paleochannel trending northwest-to-southeast across Cannon AFB is greatly improved by the addition of new, tightly spaced TDEM soundings. Many data gaps are still indicated (fig. 4), and additional data collection is needed to further improve the accuracy with which the top of the Dockum Group is depicted in areas where data remain sparse. Areas within Cannon AFB that would benefit most from additional data collection are in locations where infrastructure hindered the collection of additional TDEM soundings. The depiction of the top of the Dockum Group in areas east and south of the Cannon AFB may benefit from additional TDEM soundings, including areas where difficulty accessing private land hindered data collection.

Figure 4. Map of gridding error, top of Dockum Group on and near Cannon Air Force
                     Base in Curry County, New Mexico, 2020.
Figure 4.

Gridding error of top of Dockum Group (map shown in fig. 3) on and near Cannon Air Force Base in Curry County, New Mexico, 2020.

Paleochannel Analysis

Two methodologies were used to evaluate paleochannels in the top of the Dockum Group across the study area: (1) trend-removal grid analysis and (2) analysis with Esri’s ArcMap Hydrology toolset. Trend-removal grids were developed by removing the third-order regional trend from all the data points within the top of Dockum Group (Chinle Formation) surface grids (Seequent, 2020b). Essentially, this technique removes the regional dip of the layer prior to the process of creating surface grids. The resulting trend-removal grid (fig. 5) shows changes in the top of the Dockum Group after the regional trend was removed. Relatively low altitude values represent low-altitude data points in the top of Dockum Group (Chinle Formation) surface grid, and continuous stretches of these low-altitude values can be indicative of paleochannels. Figure 5 shows the same general northwest-to-southeast trend of paleochannel network across Cannon AFB, but with the regional trend removed, it highlights relatively deeper portions of the paleochannels. The areas in figure 5 with darker blues indicate the portions of paleochannels that are substantially deeper (more than 20 ft) relative to the main paleochannel. These deeper areas of the paleochannel indicate portions with greater saturated thickness.

Figure 5. Map shows top of Dockum Group change after regional trend removed and flow
                     lines derived from ArcMap Hydrology toolkit.
Figure 5.

Change in the top of Dockum Group after regional trend was removed and flow lines derived from ArcMap Hydrology toolkit on and near Cannon Air Force Base in Curry County, New Mexico, 2020.

The second paleochannel analysis, performed using Esri’s ArcMap Hydrology toolset, treated the surface grid representing the top of the Dockum Group as a digital surface elevation model and simulated a topographic watershed across the surface to identify the location and spatial characteristics of the paleochannel network. The toolset was used to determine the flow direction, flow accumulation, and stream order (Esri, 2021). Ultimately, the toolset simulates the movement of water across a land surface, which for this study corresponds to the top of the Dockum Group surface grid (fig. 3).

Concentric “bullseye” shapes were present in the top of Dockum Group surface contours that were not smoothed manually. For the toolset to function properly, these “bullseyes” (which act as sinks) had to be filled to render the raster hydrologically correct. Next, a flow-direction grid was created to find directional flow between cells and then used as input to the flow-accumulation tool, where a threshold lower than the default value was chosen to identify paleochannel flow paths (Esri, 2021). This flow-accumulation grid was then converted to vector format, where artifacts of the process were removed manually. The final product is a map depicting flow paths (fig. 5) based on the interpolated and smoothed top of Dockum Group altitudes. Data from previous USGS studies were used to check the results from the two methodologies used to evaluate paleochannels in the top of the Dockum Group across the study area.

These two paleochannel analysis techniques show groundwater flow direction as well as areas with the deepest saturated thickness. Hydrologically, these techniques show where aquifer storage is highest (in the deepest parts of the paleochannel network), as well as the spatial distribution of preferential groundwater flow paths (the paleochannels [fig. 5]). The analyses indicate a large paleochannel trending to the southeast with smaller channels feeding in from the west. Areas where groundwater management could be more beneficial are indicated by locations where these flow lines intersect the deeper parts of the paleochannel.

Summary

The hydrogeology on and near Cannon Air Force Base (AFB) was assessed to gain a better understanding of preferential groundwater flow paths through paleochannels. The Southern High Plains aquifer is contained in the Tertiary-age Ogallala Formation in the part of eastern New Mexico where Cannon AFB is located. The Triassic-age Chinle Formation of the Dockum Group underlies the unconfined Southern High Plains aquifer. The Southern High Plains aquifer is the primary source of water for agriculture and public supply in the area, with the sandstone and shale aquifer serving as a minor source of water mostly for agricultural uses. In and near the study area, paleochannels incised the top surface of the Dockum Group (Chinle Formation) and subsequently filled in with electrically resistive coarse-grained sediments of the overlying Ogallala Formation, resulting in a preferential groundwater flow path in the form of a paleochannel network. A better understanding of the spatial characteristics of this preferential groundwater flow path is needed to support ongoing efforts to remediate groundwater contamination at Cannon AFB. Therefore, the U.S. Geological Survey, in cooperation with the U.S. Air Force Civil Engineer Center, used surface geophysical resistivity methods and data compiled from previous studies to better understand the spatial distribution and characteristics of the paleochannel network incised into the top of the Dockum Group.

Previous studies have shown with increasing resolution how paleochannels incised the top of the Dockum Group, but limited borehole data on and near Cannon AFB continued to make accurately mapping the top of Dockum Group challenging. For this study, surface geophysical resistivity measurements in the form of time-domain electromagnetic (TDEM) soundings made by the U.S. Geological Survey were used in conjunction with data previously published by Architecture, Engineering, Construction, Operations, and Management and borehole data compiled from the New Mexico Water Rights Reporting System database to prepare an updated map of the top of the Dockum Group that includes the location and characteristics of paleochannels incised into the top of the Dockum Group (Chinle Formation). A total of 149 borehole picks were obtained from previous studies, along with 72 additional borehole picks from the New Mexico Water Rights Reporting System database and 43 borehole picks from newly collected TDEM soundings. The data were gridded and contoured using Oasis Montaj v. 9.8.1 where a kriging method using an exponential variogram model trended to the southeast was used. A map of the grid error (variance) derived from the kriging method was developed to depict where possible data gaps may still exist. The updated map of the top of Dockum Group has many areas of uncertainty greater than 20 feet because there are not enough data for the gridding process to reliably determine a value. However, this interpretation of the altitude of the top of the Dockum Group represents a substantial improvement in data resolution compared to previous studies. The resolution over the entire study area improved with the additional borehole data, and the resolution along the large paleochannel trending northwest-to-southeast across Cannon AFB is greatly improved by the addition of new, tightly spaced TDEM soundings. Many data gaps remain, and additional data collection is needed to further improve the accuracy with which the top of the Dockum Group is depicted in areas where data remain sparse.

Two methodologies were used to evaluate paleochannels in the top of the Dockum Group across the study area: (1) trend-removal grid analysis and (2) analysis with Esri’s ArcMap Hydrology toolset. Trend-removal grids were developed by removing the third-order regional trend from all the point values within the top of Dockum Group (Chinle Formation) surface grids. The resulting trend-removal grid shows changes in the top of the Dockum Group after the regional trend was removed. Relatively low values represent low-altitude points in the top of Dockum Group (Chinle Formation) surface grid and continuous stretches of these low-altitude points can be indicative of paleochannels. The grid shows the same general northwest-to-southeast trend of paleochannel network across Cannon AFB, but with the regional trend removed, it highlights relatively deeper portions of the paleochannels (more than 20 feet relative to the main paleochannel). These deeper areas of the paleochannel indicate areas with more saturated thickness. Esri’s ArcMap Hydrology toolset was used to determine the flow direction, flow accumulation, and stream order of paleochannels. A flow-direction grid was first created to find directional flow between cells, then used as input to the flow-accumulation tool, where a threshold lower than the default value was chosen to identify paleochannel flow paths. The final product is a map depicting flow paths based on the interpolated and smoothed top of Dockum Group altitudes. These two paleochannel analysis techniques show groundwater flow direction as well as areas with the deepest saturated thickness. Hydrologically, these techniques show where aquifer storage is highest (in the deepest parts of the paleochannel network), as well as the spatial distribution of preferential groundwater flow paths (the paleochannels). The analyses indicate a large paleochannel trending to the southeast with smaller channels feeding in from the west. Areas where groundwater management could be more beneficial are indicated by locations where these flow lines intersect the deeper parts of the paleochannel.

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Conversion Factors

U.S. customary units to International System of Units

Multiply By To obtain
Length
inch (in.) 2.54 centimeter (cm)
inch (in.) 25.4 millimeter (mm)
foot (ft) 0.3048 meter (m)
mile (mi) 1.609 kilometer (km)
Area
acre 4,047 square meter (m2)
acre 0.4047 hectare (ha)
acre 0.4047 square hectometer (hm2)
acre 0.004047 square kilometer (km2)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

°F = (1.8 × °C) + 32.

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

°C = (°F – 32) / 1.8.

Datum

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83) and to the World Geodetic System 1984 (WGS 84) datum.

Altitude, as used in this report, refers to distance above the vertical datum.

Abbreviations

AFB

Air Force Base

AECOM

Architecture, Engineering, Construction, Operations, and Management

EM

electromagnetic

Hz

hertz

NMWRRS

New Mexico Water Rights Reporting System

TDEM

time-domain electromagnetic

USGS

U.S. Geological Survey

For more information about this publication, contact

Director, Oklahoma-Texas Water Science Center

U.S. Geological Survey

1505 Ferguson Lane

Austin, TX 78754-4501

For additional information, visit

https://www.usgs.gov/centers/ot-water

Publishing support provided by

Lafayette Publishing Service Center

Suggested Citation

Payne, J.D., Teeple, A.P., McDowell, J., Wallace, D., and Hancock, W.A., 2022, Mapping the altitude of the top of the Dockum Group and paleochannel analysis using surface geophysical methods on and near Cannon Air Force Base in Curry County, New Mexico, 2020: U.S. Geological Survey Scientific Investigations Report 2022–5050, 21 p., https://doi.org/10.3133/sir20225050.

ISSN: 2328-0328 (online)

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Mapping the altitude of the top of the Dockum Group and paleochannel analysis using surface geophysical methods on and near Cannon Air Force Base in Curry County, New Mexico, 2020
Series title Scientific Investigations Report
Series number 2022-5050
DOI 10.3133/sir20225050
Year Published 2022
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Oklahoma-Texas Water Science Center
Description Report: iv, 21 p.; 2 Data Releases; Dataset
Country United States
State New Mexico
County Curry County
Other Geospatial Cannon Air Force Base
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details