**Gypsiferous Soil Investigations in NM**

**Greg Cates**

**MSSO Office**

**Las Cruces, NM**

**Problem:**

(a) **Soil-landform relationships.** A significant portion of White
    Sands Missile Range which includes Dona Ana, Otero, Sierra, Socorro,
    Lincoln, and Torrance Counties (Figure 1) is affected by gypsum
    (Figure 2). Extensive areas of highly gypsiferous soils also occur
    on Holloman Air Force Base and White Sands National Monument. These
    gypsiferous soils are lacustrine, alluvial, eolian and residual in
    origin. Parent materials include gypsum evaporates, gypsiferous
    sedimentary and non-gypsiferous sedimentary rocks. Some gypsiferous
    soils are salt-affected. The gypsum has been redistributed through
    geologic water (Figure 3) and wind erosion, wetting and drying
    cycles and soil forming processes producing a variety of soils and
    landforms in the Tularosa Basin. However, there is little
    information about the relationship between these gypsiferous soils
    and landforms to aid in mapping these soils.

(b) **Describing and classifying gypsiferous soil features.** When
    originally mapped (Soil Survey of White Sands Missile Range, New
    Mexico, (1976)), broadly defined map units were used. The scale was
    1:100,000 with the miscellaneous land types pertaining to gypsum as
    Active Dune Land, Gypsum ( 95,000 acres), Gypsum Land (100,500
    acres) and Gypsum Rock Land (4,800 acres). There were two soils
    series with gypsic mineralogy, Holloman and Yesum (total of 290,727
    acres) that were mapped together, individually or in conjunction
    with miscellaneous land types in this soil survey area. These broad
    map unit design concepts need re-evaluation and refinement to meet
    specific needs of military and natural resource land management.
    However, only a few studies of gypsiferous soils in Southern New
    Mexico exist. The lack of information about chemical, mineralogical
    and physical properties of these soils makes it difficult to
    describe, classify, and map these soils at the detail needed. For
    example, current NASIS rules require an entry of GYPSUM in lieu of
    texture for soil horizons with greater that 15% gypsum. However,
    gypsum contents of individual horizons have ranges that are narrower
    than 15-100%. It is assumed that these narrower ranges represent
    pedogenic process and possibly are important for interpretations.
    Questions have arisen as to:

-   petrogypsic vs. residual (bedrock) gypsum,

-   petrogypsic vs. petrocalcic,

-   contrasting family criteria

-   terms in lieu of texture for particle size distribution

-   methods of laboratory analysis for gypsum content and particle size,

-   mineral and morphological forms of gypsum within the soil and their
    relationship to pedogenesis and land forms

-   critical values of gypsum content and cementation for
    interpretations

(c) **Interpretations.** Knowledge of soil properties important for the
    management of gypsiferous soils is limited. The dominant uses of
    these soils in the Tularosa Basin are military land and national
    park recreation land. Both land managers have requirements to
    maintain, mitigate, restore, assess and monitor ecological
    functions. Information about soil-vegetation interactions is crucial
    to these land managers. Specific resource management issues include
    re-establishment of vegetation after disturbances, dust problems,
    wildlife habitat, and T&E species. Interpretations for vegetation
    potential, erosion hazard, crusting, soil fertility and
    micronutrient deficiencies in these unique gypsiferous soils are
    needed.

(d) **Objectives.**

> 1\) develop concepts, categories and terms to describe and classify
> highly gypsiferous soils;
>
> 2\) examine and identify unique morphologies and soil-landform
> relationships for consistent field mapping;
>
> 3\) identify the relationships between gypsiferous soil properties and
> plant communities to aid in soil mapping and interpretations;
>
> 4\) determine gypsum-related soil properties (e.g., gypsum content,
> crusting potential, water holding capacity) important for military
> land management and develop interpretations and
>
> 5\) establish meaningful property terms for soil survey databases.
>
> **Justification**
>
> Gypsiferous soils comprise about 1,000,000 + acres in New Mexico. The
> Soil Survey of White Sands Missile Range is currently being updated as
> per contract with Department of Defense and is also a part of the MLRA
> 42 update program. New information about the soils' genesis,
> distribution, physical and chemical properties will support these
> projects as well as those in neighboring states. The information
> gained in this study will improve the soil mapping progress. It will
> also be available to support the addition of new attributes to NASIS
> for unique gypsiferous properties necessary to generate
> interpretations. This will lead to better interpretations and
> increased credibility for soil survey products. This study will also
> help the soil survey party in recognizing new series and further help
> define established soil series.
>
> **Background**
>
> [Setting]{.underline} The area to be sampled is in the Tularosa Basin,
> a closed basin in south-central New Mexico with Lake Lucero at the
> lowest point. The gypsum originated from dominantly the Yeso Formation
> (middle Permian in age) which can be up to 1500 feet thick. The Yeso
> formation occurs on both the San Andres Mountains to the west and the
> Sacramento Mountains to the east. The climate is typic-aridic and
> ustic-aridic, with 6 to 12 inches of precipitation. The temperature
> regime is thermic.
>
> With no drainage outlet, the Tularosa basin traps and concentrates all
> the dissolved gypsum that comes from the Yeso Formation in the
> surrounding mountains, gypsum that would normally be carried away by
> rivers and streams. Through many wet and dry cycles during the late
> Pleistocene, lake levels would rise and fall, dissolving and then
> precipitating the gypsum. The predominant southwest wind during dryer
> climates moved and is currently moving the gypsum in a northeastly
> direction forming a large active gypsum dune field and providing a
> constant source of gypsum to soils on the adjacent piedmont slope.
> Quaternary surfaces are identified in Seager, et al.
>
> [Existing soils]{.underline} This study would focus on the
> distribution, cementation, size, amount, and type of gypsum present in
> the soil and at what depths. The sample sites will include soils at
> the lower elevations through the higher elevations where these
> gypsiferous soils occur. Representative soils on dominant geomorphic
> surfaces and landforms will be included (Figure 4). Existing series
> are listed in the table. Laboratory data from various pedons indicates
> soil gypsum contents of 30 to 90+ percent for individual horizons.
>
> **Highly gypsiferous soil series in White Sands Missile Range.**

  ----------------------- ----------------------- -----------------------
  **Existing series**     **Classification**      **Gypsum content**

  Holloman                Loamy, gypsic, thermic, 60-90+ percent
                          shallow Typic           
                          Torriorthents           

  Yesum                   Coarse-loamy, gypsic,   60-90+ percent
                          thermic Leptic          
                          Haplogypsids            
  ----------------------- ----------------------- -----------------------

> [Previous work]{.underline}
>
> A study of gypsiferous soils (attached letter by Warren Lynn, NSSL,
> dated June 25, 1981) did not resolve the still unanswered questions on
> particle size determination, taxonomy and pedogenic morphology for
> soils high in gypsum. Articles on gypsum are included in the reference
> section.
>
> Pedon data from Otero County in earlier sampling:
>
> S01NM-035-013
>
> S01NM-035-014
>
> Recent field work and research have revealed morphological features
> unique to these soils. Adequate terminology for some of these features
> is not currently available in the *Field Book for Describing and
> Sampling Soils*. Other features can be described using the field
> guide, but their relationship to pedogenesis or interpretations is not
> well understood. The features that have important significance for
> soil genesis and soil behavior require well defined criteria,
> definitions and concepts. Once this has been done, the questions of
> soil-landform relationships, soil classification, and soil
> interpretations can be addressed. (Table 1)
>
> **Table 1. Probable importance of morphological features and taxonomic
> terms in highly gypsiferous soils.**

  -------------------- ------------ ----------- --------------- ------------------- ----------------
  Morphological        Important                                                    
  feature              for:                                                         

                       In lieu of   Indicator   Relationship to Likelihood to form  Predicting
                       texture for  for         water holding   a physical-chemical hazards to
                       describing   geogenic    capacity,       crust after         military
                       and mapping  vs.         nutrient        disturbance and/or  equipment,
                       soil         pedogenic   availability,   truncation          infrastructure
                                    gypsum      plant community                     and personnel

  **Soil matrix**                                                                   

  "Gyp sugar"          ?                        ?               ?                   

  "Gyp flour"          ?                        ?               ?                   

  "Gyp tuff"                        ?           ?               ?                   

  "Gyp nodules"                     ?                                               
  (photo)                                                                           

  Gypsum content       ?                        ?               ?                   

  Mineral form of      ?            ?           ?               ?                   
  gypsum                                                                            

  Dilatency (photo)    ?                        ?               ?                   

  Cementing agent                   ?                           ?                   

  Continuity of                     ?           ?                                   
  cementation                                                                       

  Rupture resistance   ?                        ?               ?                   
  of cemented material                                                              

                                                                                    

  **Concentrations**                                                                

  Gypsum crystals                   ?                           ?                   

  Snow ball morphology              yes         ?               ?                   
  (Buck and Van                                                                     
  Hoesen, 2002)                                                                     

  Powdery gypsum       ?            ?           ?               ?                   

  Root concretions                  ?                                               
  (photo)                                                                           

  Selenite bands                    ?                                               
  (photo)                                                                           

                                                                                    

  **Structure and                                                                   
  cracks**                                                                          

  Macro peds (photo)                ?                                               

  Oblique fractures                 ?                                               
  (photo)                                                                           

  Physico-chemical                  ?                           ?                   
  crust (photo)                                                                     

  **Taxonomic terms**                                                               

  Gypsic                                                                            

  Hypergypsic                                                                       

  Hypogypsic           ?            ?           ?               ?                   
  -------------------- ------------ ----------- --------------- ------------------- ----------------

> **Information Needed**
>
> A soil-geomorphic study is appropriate to determine the
> characteristics and extent of the gypsum dominated sediments across
> the landscape. The study needs to include a literature review, an
> initial phase for reference samples, a soil-geomorphology assistance
> visit and a second phase for full characterization data collection on
> a soil-vegetation-geomorphic basis. The objective of the initial phase
> is to develop concepts, categories and terms to describe and classify
> highly gypsiferous soils. Knowledge gained from the initial phase will
> help insure high quality site selection and improve horizon
> designations and descriptions of the soils.
>
> From this study we can expand our knowledge of the geomorphology and
> pedogenesis and gain a greater understanding of gypic soils and their
> use and management
>
> **Action and Assignments**
>
> 1\. The initial study will be in August 28 through September 1 of
> 2006.
>
> 2\. The MLRA office (MLRA 42) requests the assistance of the staff at
> the National Soil Survey Center in Lincoln, NE..
>
> 3\. The coordinators for the study will be the Las Cruces Soil Survey
> Project Leader and the New Mexico State Soil Scientist.
>
> 4\. The Las Cruces Soil Survey Office will coordinate the issuing of
> access badges for the soil sampling team in August 2005.
>
> 5\. Soil Pits will be dug with a backhoe beforehand and described
> prior to the collection of the samples.
>
> 6\. The second phase, to be conducted in the fall of 2007 and will
> include soils on additional landforms to fully develop the
> soil-landform relationships and interpretations. Additional phases
> will be needed as mapping continues on the range.
>
> 7\. The results of this study will be used to guide the Las Cruces SSO
> in their mapping efforts on the White Sands Missile Range.
>
> **Assistance Requested from NSSC**
>
> Initial phase:
>
> Number of Pedons -- 10 (Depending on range access and time
> constraints)
>
> Number of Samples -- Approximately 40 to 60
>
> Second phase:
>
> Number of Pedons: 8
>
> Number of Samples: 30 to 50
>
> Sites to be Sampled: 8

+----------------------+-----------------------+----------------------+
| **Tentative,         | **Classification**    | **Tentative Acres**  |
| Proposed and         |                       |                      |
| Established series & |                       |                      |
| NASIS Site ID**      |                       |                      |
+----------------------+-----------------------+----------------------+
| Basso (T)            | Fine-loamy, mixed,    | 1,000                |
|                      | superactive, themic   |                      |
| 2005NM688003         | Calcic Argigypsids    |                      |
+----------------------+-----------------------+----------------------+
| Corvus (T)           | Loamy, gypsic,        | 3,000                |
|                      | thermic, shallow      |                      |
| 2005NM688006         | Typic Petrogypsids    |                      |
+----------------------+-----------------------+----------------------+
| Flake (T)            | Fine-loamy, mixed,    | 30,000               |
|                      | superactive, thermic  |                      |
| 2005NM688015         | Typic Haplogypsids    |                      |
+----------------------+-----------------------+----------------------+
| Hermes (T)           | Coarse-loamy, gypsic, | 30,000               |
|                      | thermic Leptic        |                      |
| 2005NM688001         | Haplogypsids          |                      |
+----------------------+-----------------------+----------------------+
| Loki (T)             | Coarse-loamy, gypsic, | 20,000               |
|                      | thermic Typic         |                      |
| 2005NM688017         | Calcigypsids          |                      |
+----------------------+-----------------------+----------------------+
| Matador (T)          | Coarse-loamy, gypsic, | 1,000                |
|                      | thermic Gypsic        |                      |
| 2005NM688012         | Haplosalids           |                      |
+----------------------+-----------------------+----------------------+
| Peligro (T)          | Coarse-loamy, gypsic, | 3,000                |
|                      | thermic Leptic        |                      |
| 2005NM688002         | Haplogypsids          |                      |
+----------------------+-----------------------+----------------------+
| Talos (T)            | Fine, mixed,          | 30,000               |
|                      | superactive, thermic  |                      |
| 2005NM688014         | Calcic Argigypsids    |                      |
+----------------------+-----------------------+----------------------+
| Yesum (E)            | Coarse-loamy, gypsic, | 20,000               |
|                      | thermic Leptic        |                      |
|                      | Haplogypsids          |                      |
+----------------------+-----------------------+----------------------+

[Other interested individuals.]{.underline}

> The following individuals have experience and stated interests in this
> investigation of gypsiferous soils.
>
> **Dr. Curtis Monger, Associate Professor, Dept of Agronomy and
> Horticulture, NMSU <cmonger@nmsu.edu>**
>
> **Dr. April Ulery, Associate Professor, Dept of Agronomy and
> Horticulture, NMSU <aulery@nmsu.edu>**

Comments from April:

> Characterization of mineralogy; improvement of particle size
> distribution method using laser analysis; total elemental analysis to
> determine soil fertility and nutrient interaction with native plants.
>
> **Dr. Brenda Buck, Associate Professor, University of Nevada, Las
> Vegas, <buckb@unlv.nevada.edu>**
>
> **Arlene Tugel, Soil Scientist Liaison to ARS, NRCS, Las Cruces, NM**
>
> **atugel@nmsu.edu**
>
> **Jeff Herrick, Research Soil Scientist, Jornada Experimental Range,
> ARS, Las Cruces, NM**
>
> **jherrick@nmsu.edu**
>
> References

Allen, B.D. 1991. Effect of climatic change on Estance Valley, New
Mexico: sedimentation and landscape evolution in a closed-drainage
basin. In: Julian, B., Zidek, J. (Editors), Field Guide to Geologic
Excursions in New Mexico and Adjacent Areas of Texas and Colorado, New
Mexico Bureau of Mines and Mineral Resources, Socorro, USA, pp. 166-171.

Almendinger, R.J. and Titus, F.B., 1973, Regional hydrology and
evaporative discharge as present-day source of gypsum at White Sands
National Monument, New Mexico: New Mexico Bureau of Mines and Mineral
Resources Open File Report 55, 26p.

Almendinger, R.J., 1972. Hydrologic control over the origin of gypsum at
Lake Lucero, White Sands National Monument, New Mexico. Master's Thesis,
New Mexico Institute of Mining and Technology, Socorro, New Mexico,
United States, 182pp.

Almendinger, R.J., 1971. Preliminary evaluation of the role of the
hydrologic cycle in the development of the white sands, White Sands
National Monument, New Mexico, Abstracts with Programs-Geological
Society of America 3, 231-232.

Anderson, B.D., Menking, K.M, 2002. Geomorphic Expression of Abrupt
Climate Change in Southwestern North America at the Glacial Termination.
Quaternary Research 57, pp. 371-381. {Focuses on gypsum landforms of
Lake Estancia}

Bachhuber, F.W., 1982 Quaternary History of the Estancia Valley, Central
New Mexico. In: Callender, J.F., Grambling, J.A., Wells, S.G. (editors)
New Mexico Geological Society Guidebook: Albuquerque Country II,
Socorro, USA, Vol. 33, pp. 343-346.

Basabilvazo, G.T., Myers, R.G., Nickerson, E.L. 1994. Geohydrology of
the high energy laser system test facility site, White Sands Missile
Range, Tularosa Basin, south central New Mexico. U.S. Geological Society
of America Bulletin 102, 749-759.

Belnap, J., Kaltenecker, R., Rosentreter, J., Williams, S., Leonard, D.
Eldridge, 2001. Biological soil crusts: ecology and management,
TR-1730-2, US Department of the Interior, Denver, CO, 2001.

Belnap, J. 1993. Recovery rates of cryptobiotic crusts: inoculant use
and assessment methods. Great Basin Naturalist 53, pp. 89-95.

Blair, T.C., Clark, J.S., Wells, S.G. 1990. Quaternary continental
stratigraphy, landscape evolution, and application to archeology:
Jarilla Piedmont and Tularosa graben floor, White Sands Missile Range,
New Mexico; with Supplementary Data 90-08. Geological Society of America
Bulletin, 102, 749-759.

Bockheim, J.G., Gennadiyev, A.N., 2000. The role of soil-forming
processes in the definition of taxa in Soil Taxonomy and the World Soil
Reference Base. Geoderma 95, 53-72.

Boyadgiev, T.G., Verheye, W.H., 1996. Contribution to a utilitarian
classification of gypsiferous soil. Geoderma 74, pp. 321-338.

Boyadgiev, T.G. 1974, *Contribution to the knowledge of gypsiferous
soils.* AGON/SF/SYR/67/522. FAO, Rome

Buck, B.J., Van Hoesen, J.G., 2005. Assessing the applicability of
Isotopic Analysis of Pedogenic Gypsum as a Paleoclimate Indicator in
Southern New Mexico. Journal of Arid Environments 60, 99-114.

Buck, B.J., Van Hoesen, J.G., 2002. Snowball morphology and SEM analysis
of pedogenic gypsum, southern New Mexico, Journal of Arid Environments
51, 469-487.

Buck, B.J., Monger, H.C., 1999. Stable isotopes and soil-geomorphology
as indicators of Holocene climate change northern Chihuahuan Desert.
Journal of Arid Environments, 43, 357-373.

Calaforra, J.M., Pulido-Bosch, A., 1999. Genesis and Evolution of Gypsum
Tumuli. Earth Surface Processes and Landforms 24, 919-930.

Campo, J.G., Alberto, F., Hodgson, J., Garcia-Ruiz, J.M.,
Montserrat-Marti, G., 1999. Plant community patterns in a gypsum area of
NE Spain. I. Interactions with topographic factors and soil erosion.
Journal of Arid Environments 41, pp 401-410.

Carter, B.J., Inskeep, W.P., 1988. Accumulation of pedogenic gypsum in
Western Oklahoma soils. Soil Science Society of America Journal 52,
1107-1113.

Chen, Xiang Yang, 1997. Pedogenic gypcrete formation in arid central
Australia. Geoderma 77, pp. 39-61.

Dana, E.D., Mota, J.F., 2006. Vegetation and soil recovery on gypsum
outcrops in semi-arid Spain. Journal of Arid Environments 65,
pp.444-459.

Eldridge, D. J. and R. S. B. Greene. 1994e. Microbiotic soil crusts: a
review of their roles in soil and ecological processes in rangelands of
Australia. Australian Journal of Soil Research 32: pp. 389-415.

Eshel, G., Levy, G.J., Mingelgrin, U., Singer, M.J. 2004. Critical
Evaluation of the Use of Laser Diffraction for Particle-Size
Distribution Analysis. Soil Science of America Journal 68, pp.736-743.

Eswaran, H and Zi-Tong, G. 1991. Properties, genesis, classification and
distribution of woils with gypsum. In: Nettleton, W.D, 1991. Occurrence,
Characteristics and Genesis of Carbonate, Gypsum and Silica
Accumulations in Soils. Soil Science Society of America Special
Publication 26, Madison, Wisconsin

Food and Agriculture (FAO), 1990. Management of Gypsiferous Soils. Soil
Resources, Management and Conservation Service, FAO Land and Water
Development Division, Food and Agriculture Organization of the United
Nations, Soils Bulletin 62, Rome.

Food and Agriculture (FAO)/ISRIC/ISSS, 1998. World reference base for
soil resources. World Resources Report, Vol. 84, FAO Rome.

Frenkel, H., Gerstl, Z., Renger van de Veen, J., 1986. Determination of
gypsum and cation exchange capacity in arid soils by a resin method.
Geoderma 39 (1), pp. 67-77.

Fryberger, S. Geological Overview of White Sands National Monument. 2006
Available on line at
<http://www2.nature.nps.gov/geology/parks/whsa/geows/index.htm>

Gee, G.W., Bauder, J.W., 1986. Particle Size Analysis. In: Methods of
Soil Analysis, Part 1-Physical and Mineralogical Methods. Soil Science
Society of America Book Series 5, American Society of Agronomy, Inc.,
Madison, Wisconsin pp. 383-411.

Gile, L.H., Peterson, F.F., Grossman, R.B., 1966. Morphological and
genetic sequences of carbonate accumulation in desert soils. Soil
Science 101, 347-360.

Gile, L.H. (1975) Holocene Soils and Soil-Geomorphic Relations in an
Arid Region of Southern New Mexico, Quaternary Research 5, 321--360

Gile, L.H., Peterson, F.F., Grossman, R.B., 1981. Soils and
Geomorphology in the Basin and Range Area of Southern New
Mexico-Guidebook to the Desert Project, New Mexico Bureau of Mines and
Mineral Resources, Memoir 39.

Gould, C. N. 1939. The great White Sands (of New Mexico). Mines
Magazine, 29 379-381.

Harden, J.W., Taylor, E.M., McFadden, L.D., Reheis, M.C. 1991. Calcic,
gypsic and siliceous soil chronosequences in arid and semiarid
environments. Soil Science Society of America Special Publication 26, pp
1-16.

Hawley, J.W., 1993. Geomorphic setting and late Quaternary history of
pluvial-lake basins in the southern New Mexico Region: New Mexico Bureau
of Mines and Mineral Resources, Socorro, New Mexico, Open File Report
391, pp 28.

Herrero, J., 2004. Revisiting the definitions of gypsic and petrogypsic
horizons in Soil Taxonomy and World Reference Base for Soil Resources.
Geoderma 120, pp. 1-5.

Herrero, J., Porta, J., 2000. The terminology and the concepts of gypsum
rich soils. Geoderma 96, pp. 47-61.

Herrero, J., Porta, J., Fedoroff, N., 1992. Hypergypsic soil
micromorphology and landscape relationships in northeastern Spain. Soil
Science Society of America Journal 56, pp. 1188-1194.

Herrick, C.L. (1900) The geology of the White Sands of New Mexico, Jour.
of Geology vol 8, p 112--128

Herrick, C.L., 1904. Lake Otero, an ancient salt lake basin in
southeastern New Mexico, Economic Geology 4, 174-189.

Hesse, P.R., 1976. Particle size distribution in gyspsic soils. Plant
and Soil 44, pp. 241-247.

Holliday, V.T., 1997. Origin and Evolution of Lunettes on the High
Plains of Texas and New Mexico. Quaternary Research 47, pp. 54-69.

Jafarzadeh, A.A., Burnham, C.P., 1992. Gypsum crystal in soils. Journal
of Soil Science 43, (3), pp.409-420

Jones, B.R., 1959. A sedimentary study of dune sands. Lamb and Bailey
Counties, Texas, and White Sands National Monument, New Mexico. Master's
Thesis, Texas Tech University, Lubbock, Texas, USA. 95pp.

Khademi, H. Mermut, A.R., 2003. Micromorphology and classification of
Argids and associated gypsiferous Aridisols from Central Iran. Catena
54, pp. 439-455.

Kottlowski, F.E., Lindsay, R.F., Lemone, D.V., Soreghan, G.S., 1994.
Field trip road logs, Day 1: Hembrillo Basin and White Sands. In:
Garber, R.A., Keller, D.R., (editors), Field Guide to the Paleozoic
Section of the San Andres Mountains: Midland Texax, Permian Basin
Section-SEPM Publication 94-35, pp. 1-16.

Kottlowski, F.E. 1958. Lake Otero: second phase in formation of New
Mexico's gypsum dunes. Geological Society of America Bulletin 69,
1733-1734.

Langford, Richard, P. 2003. The Holocene history of White Sands dune
field and influences on eolian deflation and playa lakes. Quaternary
International 104, p 31-39.

LeMone, D.V. 1987. White Sands national Monument New Mexico: In Garber,
R.A., Keller, D.R. (editors). Centennial Field Guide Rocky Mountain
Section of the Geologcial Society of America, pp. 451-454

LeMone, D.V. 1994. White Sands national Monument New Mexico: In: Garber,
R.A., Keller, D.R., (editors), Field Guide to the Paleozoic Section of
the San Andres Mountains: Midland Texax, Permian Basin Section-SEPM
Publication 94-35, pp. 155-158.

Lueth, Virgil,. Giles, Katherine A., Lucas, Spencer G.,. Kues, Barry S.,
Myers, Robert G., and Ulmer-Scholle, Dana (editors). 2002, New Mexico
Geological Society Guidebook 53 Geology of White Sands, 362p.

Mack, G. H., Sugio, K. 1991. Depositional Environments of the Yeso
Formation (Middle Permian), Southern Caballo Mountains, New Mexico
Geology 13, 45-47.

McKee, Edwin, D. Editor. 1979. A study of Global Sand Seas. U.S.
Geological Survey Professional Paper 1052. United States Government
Printing Office 1979, p 3-19.

McKee, Edwin, D. and Moiola, R.J. 1975. Geometry and growth of White
Sands dune field, New Mexico. U.S. Geological Survey Journal of
Research, v.3, p. 59-66.

McKee, Edwin, D. and Douglass, J.R. 1971. Growth and movement of dunes
at White Sands National Monument, New Mexico, U.S. Geological Survey
Professional Paper 750-D, p.D108-D114.

Mckee, Edwin, D., van Houten, F.B., 1966. Structures of dunes at White
Sands National Monument, New Mexico (and a comparison with structures of
dunes from other selected areas): Sedimentology, v. 7, p 3-69.

McLean, J.S., 1970. Saline ground-water resources of the Tularosa Basin,
New Mexico, Report No. 561. U.S. Office of Saline Water Research and
Development Progress Report, Vol. 571, p.128.

McLean, J.S. 1970. Objectives of a current study of saline ground water
in the Tularosa Basin, New Mexico: In 15^th^ Annual Water Conference of
the New Mexico Water Resources Research Institute Proceedings, New
Mexico, pp.95-100

Meinzer, O.E., 1922. Map of the Pleistocene Lakes of the Basin and Range
Province and Its Significance: Geological Society of America Bulletin,
Vol 33, pp. 541-552.

Meinzer, O.E. and Hare, R.F. (1915) Geology and Water Resources of
Tularosa Basin, New Mexico. U.S. Geological Survey Water-Supply Paper
343, 317p.

Meyer, S. E. 1986. The ecology of gypsophile endemism in the eastern
Mojave Desert. Ecology 67, pp. 1303-1313.

Meyer, S. E. and E. García-Moya. 1989. Plant community patterns and soil
moisture regime in gypsum grasslands of north central Mexico. Journal of
Arid Environments 16, pp. 147-155.

Monger, H.C., Gallegos, R. 1997. Mineralogy and eolian
sedimentation-Lost River Playa, Otero County, New Mexico. Report
submitted to Geo-Marine Inc., New Mexico State University, Las Cruces,
New Mexico 16pp.

Myer, S.E., Garcia-Moya, E., Lagunes-Espinoza, L., 1992. Topographic and
soil surface effects on gypsophile plant community patterns in Central
Mexico. Journal of Vegetation Science 3, 429-438.

Myers, R.G. 1983. Test wells T21, T22 and T25 and White Sands Missile
Range, Dona Ana County, New Mexico. U.S. Geological Survey, Reston
Virginia. 37pp.

Myers, R.G., Pinckley, K.M., 1987. Test wells TW1, TW2 and TW3, White
Sands Missile Range, Otero County, New Mexico. U.S. Geological Survey,
Reston, Virginia, USA 19pp.

Myers, R.G., Sharp, S.C., 1989. Biannual water-resources review White
Sands Missile Range, New Mexico 1986 and 1987, . U.S. Geological Survey,
Reston Virginia. 36 pp.

Myers, R.G., Sharp, S.C., 1992. Annual water-resources review White
Sands Missile Range, New Mexico 1988. U.S. Geological Survey, Reston
Virginia. 23 pp.

Neal, J.T., Smith, R.E. and Jones, B.F. (1983) Pleistocene Lake Trinity,
An Evaporite Basin in the Northern Jornada Del Muerto, New Mexico, p
285--290 New Mexico Geological Society Guidebook, 34th Field Conference,
Socorro Region II

Nelson, R.E., Klameth, L.C., Nettleton, W.D., 1978. Determining soil
gypsum content and expressing properties of gypsiferous soils. Soil
Science Society of America Journal 42, 659-661.

Nettleton, W.W., 1991. Occurrence, Characteristics and Genesis of
Carbonate, Gypsum and Silica Accumulations in Soils. Soil Science
Society of America Special Publication 26, Madison, Wisconsin.

Nettleton, W.W., Nelson, R.E., Brasher, B.R., Derr, P.S., 1982.
Gypsiferous soils in Western United States. In: Kittrick, J.A., Fanning,
D.S. Hossner, L.R., Krai, D.M., Hawkins, S. (editors), Acid Sulfate
Weathering Soil Science Society of America Special Publication 10: Soil
Science Society of America Special Publication 26, Madison, Wisconsin,
pp. 147-168.

Orr, B.R. and Myers, R.G. (1986) Water resources in basin-fill deposits
in the Tularosa Basin, New Mexico: U.S. Geological Survey Water
Resources Investigations Report 85-- 4219, 94p.

Palmeri, A., Sauro, U., 2002. Solution and recrystallisation processes
and associated landforms in gypsum outcrops of Sicily. Geomorphology 49,
25-43.

Poch, R.M., and Verplancke, H., 1997. Penetration resistance of
gypsiferous horizons. European Journal of Soil Science 48, 535-543.

Pock, R.M., DeCoster, W., Stoops, G., 1998. Pore space characteristics
as indicators of soil behaviour in gypsiferous soils. Geoderma 87, pp.
87-109.

Porta, M., 1998. Methodologies for the analysis and characterization of
gypsum in soils: A Review. Geoderma 87, pp. 31-46.

Porta, J., Herrero, J., 1990. Micromorphology and genesis of soils
enriched with gypsum. In: Douglas, L.A. (editor) , Soil Micromorphology:
A Basic and Applied Science, Elsevier, Amsterdam, pp. 321-339.

Pye, K., Blott, S.J., 2004. Particle Size analysis of sediments, soils
and related particulate materials for forensic purposes using laser
granulometry. Forensic Science International 144, pp. 19-27. (laser
particle size analysis)

Reid, W.H. (1980) Final Report: White Sands National Monument Natural
Resources and Ecosystem Analysis, CX702900001. Volume 1, Report of
Studies. Laboratory for Environmental Biology, University of Texas at El
Paso Research Report Number 12

Rivers, E.D., Hallmark, C.T., West, L.T., Drees, L.R., 1982. A Technique
for Rapid Removal of Gypsum from Soil Samples. Soil Science Society of
America Journal Vol. 46, pp. 1338-1342,

Rosen, M.R., 1994. The importance of groundwater in playas; a review of
playa classifications and the sedimentology and hydrology of playas.
Paleoclimate and basin evolution of playa systems. Special Paper
Geological Society of America 289, pp 1-18.

Ruhe, R.V., 1967. Geomorphic surfaces and surficial deposits in Southern
New Mexico. New Mexico Bureau of Mines and Mineral Resources, Memoir 18,
65pp.

Schenk, C.J., Fryberger, S.G. 1988. Early diagenesis of eolian dune and
interdune sands at White Sands, New Mexico. In: Hesp, P., Fryberger,
S.G. (editors), Eolian Sediments, Vol. 55. Elsevier, Amsterdam,
Netherlands, pp. 109-120.

Seager, W.R. 1980. Quaternary fault system in the Tularosa and Hueco
basins, southern New Mexico and West Texas. In: Dickerson, P.W., Hoffer,
J.M., Callender, J.F., (editors), Trans-Pecos Region: Southeastern New
Mexico and West Texas Guidebook of the New Mexico Geological Society,
New Mexico Geological Society, Socorro, Vol. 31 pp 1311-135.

Seager, W., Hawley, J., Kottlowski, F.E., Kelly, S.A. 1987. Geology of
the East Half of the Las Cruces and Northeast El Paso 2-degree Sheets
Southern New Mexico. New Mexico Bureau of Mines and Mineral Resources,
Socorro.

Smith, G.I., Street-Perrott, F.A., 1983. Pluvial lakes of the western
United States. In: Porter, S.C. (editor) *Late Quaternary Environments
of the United States,* Vol. 1 pp. 190-212. The Late Pleistocene,
Minneapolis: University of Minnesota Press.

Smith, L.N., Anderson, R.Y. 1982. Pleistocene-Holocene Climate of the
Estancia Basin, central New Mexico. In: Callender, J.F., Grambling,
J.A., Wells, S.G. (editors) New Mexico Geological Society Guidebook:
Albuquerque Country II, Socorro, USA, Vol. 33, pp. 347-350.

Sokolovich, V.E., Evdokimova, L.A., 1997. Accelerated Method of
Determining Gypsum Content in Soils and Rocks. Soil Mechanics and
Foundation Engineering, Vol 34 (no. 2) pp.64-65.

Stern, R., Alperovitch, N., Levy, G.J., 1989. Rapid Removal of Gypsum by
Resin Prior to Particle Size Distribution Analysis in Soils. Soil
Science Vol. 148 (No. 6) pp. 448-450.

Stoops, G., Ilaiwi, M., 1981. Gypsum in arid soils, morphology and
genesis, p. 175-185. In: F.H. Beinroth and A. Osman (editors),
Proceedings 3^rd^ International Soil Classification Workshop, 14-23 Apr
1980, Arab Center for the Studies of Arid Zones and Drylands, Damascus,
Syria.

Talmadge, S. B., 1933. Source and growth of the white sands of New
Mexico. Pan-American Geologist, 60, 304.

Taimeh, A.Y., 1992. Formation of gypsic horizons in some arid regions of
Jordan. Soil Science 153, 486-498.

Toomanian, N, Jalalian, A., Eghbal, M.K., 2001. Genesis of gypsum
enriched soils in north-west Isfahan, Iran. Geoderma 99, pp. 199-224.

United States Department of Agriculture (USDA), United States Salinity
Laboratory Staff. 1954. Diagnosis and improvement of saline and alkali
soils. U.S.D.A. Handbook 60, pp 166.

Vandiver, V.W. (1936) Geological Report on White Sands National
Monument, National Park Service, Southwestern Monuments supplement for
May, 1936, p. 381--400.

Van Hoesen, J., 2000. Pedogenic gypsum in southern New Mexico; genesis,
morphology, and stable isotopic signature. \[M.S. Thesis\]: Las Vegas,
University of Nevada Las Vegas,

182 p.

Van Hoesen, J., Buck, B.J., 1999. Morphology and Genetic Sequences of
Pedogenic Gypsum Accumulation in Holocene and Late-Pleistocene Buried
Soils in Southern New Mexico. 1999 Geological Society of America
Meeting, Denver, Colorado, Abs. No 51307.

Verhaye, W.H., Boyadgiev, T.G., 1997. Evaluating the land use potential
of gypsiferous soils from field pedogenic characteristics.Soil Use and
Management 13, pp. 97-- 103.

Weber, R.H. and Kottlowski, F.E. (1959) Gypsum Resources of New Mexico.
New Mexico Institute of Mining & Technology. State Bureau of Mines and
Mineral Resources Bulletin 68

Wier, J.E., Jr., 1965, Geology and availability of ground water in the
northern part of the White Sands Missile Range and vicinity, New Mexico,
U.S. Geological Survey Water-Supply Paper 1801, 78p.

Wilkins, D.E., Currey, D.R., 1997 Timing and Extent of Late Quaternary
Paleolakes in the Trans-Pecos Closed Basin, West Texas and South-Central
New Mexico. Quaternary Research 47, pp. 306-315.

Yechieli, Y, Wood, W.W., 2002. Hydrogeologic processes in saline
systems: playas, sabkhas, and saline lakes. Earth-Science Reviews 58,
pp. 343-365.

F

**Figure 1**

> **Figure 2**

Figure

> **Figure 3**
>
> **Midwest TSC**
>
> Federal Building, Room 393
>
> 100 Centennial Mall North, Box 82503 Lincoln, NE 68501
>
> FTS 541-5363; Commercial 402-471-5363

subiect 430-SOILS - Texas, 1979: Reeves County - Gypsic Soils
(CP79-TX122)

> To: C. M. Thompson
>
> State Soil scientist
>
> W. R. Poage Federal Building 101 South Main Street
>
> P.O. Bo 648
>
> Temple TX 76501
>
> Attached are eight copies of data and descriptions for pedons of
> Holloman S78TX-389-1, Orla S78TX-389-2, Saragosa S78TX-389-3 and
> S78TX-389-4. Mineralogy data have been added since the last
> distribution, November 16, 1979. Soluble fluoride has been placed on
> data sheets. This completes analyses requested in your letter of
> February 26, 1979. I understand that these data may serve as a base
> for continued study of gypsic soils in West Texas. I have collected
> some background material in our file that may be useful if additional
> studies are undertaken. Partly completed SCS-SOILS-8 forms are
> enclosed. Please complete the forms and forward to Joe Nichols at the
> STSC.
>
> Comments included with the November 16, 1979 distribution are also
> included here. Dennis Nettleton and Reuben Nelson reviewed the data
> and comments. Some of their thoughts are attached.
>
> If you have questions, ^p^lease call.
>
> ![](media/image1.png){width="1.9805555555555556in"
> height="0.5131944444444444in"}
>
> WARREN C. LYNN Liaison to the South
>
> National Soil Survey Laboratory
>
> Attachments
>
> cc:
>
> J. D. Nichols, Head, Soils Staff, STSC, SCS, Fort Worth, TX
>
> L. P. Wilding, Dept. of Soil & Crop Science, Texas A&M Univ., College
> Station, TX **B.** Harris, Dept. of Soil & Crop Science, Texas A&M
> Univ., College Station, TX

B.  L. Allen, Dept. of Soils, Texas Tech Univ., Lubbock, TX

C.  **S**. Holzhey, Head**,** NSSL, MTSC, SCS, Lincoln, NE

> **The Soil Conservation Service** SCS\--.S‑
>
> Is **an agency of me .n..**

*REEVES COUNTY, TEXAS\
GYPSIC SOILS\
PROJECT CP79-TX122*

Comments by Warren Lynn, November 1, 1979

The high content of gypsum presents problems in analyses and in the
reporting of data. For particle-size analysis, samples were washed to
remove the gypsum. However, it is difficult to be certain that all the
gypsum is removed in this process. Particle-size (let: are reported as
if on a gypsum-free base. For other analyses that are normally reported
on an oven-dry base, the water of hydration associated with gypsum
(CaSO~\`~•2H O) has been calculated back into the date as reported. The
two molecules of water are lost when gypsum is dried at 110 C.

> When I attempted to classify the pedons according to Soil Taxonomy,
> more questions arose than I could handle. At this stage, I think it is
> better to raise the questions for your consideration and let you
> suggest the placements.

[Gypsic Family Mineralogy]{.underline} (Soil Taxonomy, p. 387)

All four pedons have sufficient gypsum to qualify for gypsic family
mineralogy.

[Diaguostic Gypsic Horizon]{.underline} (Soil Taxonomy, p. 46)

Only Orla S7dTX-389-2 has a gypsum distribution with depth that suggests
a zone of accumulation within the context of a diagnostic gypsic
horizon. Even in this case, the presence of a buried soil raises the
question of stratigraphic vs. pedogenic distribution of gypsum. Is there
a lithologic change associated with the buried soil in this pedon?

The Holloman S78TX-389-1 pedon has a diagnostic gypsic horizon (66 to 68
percent gypsum at 3-48 cm vs. 59 percent gypsum at 48-69 cm) if the data
are applied strictly. Precision is about =1% absolute.

[Salic Horizon]{.underline} Soil Taxonomy, p. 47)

Only the pedon of Saragosa S78TX-389-3 has a salic horizon (0-28 cm).

[Family Particle-size Classes]{.underline}

Assignment of the family particle-size classes poses problems. *Should*
the gypsum be considered sand or silt or some combination of the two? I
assumed that enough of the gypsum was sand size to exclude placement in
silty particle-size classes. The descriptions of Saragosa indicate a
silty family while the descriptions of the other two soils indicate
loamy families. I need some kelp in determining how to assign the gypsum
to sand or silt.

[Typic Gypsiorthids]{.underline} (Soil Taxonomy, p. 175)

There is plenty of gypsum to meet the requirements for Typic
Gypsiorthids as outlined in Soil Taxonomy. However, my understanding is
that a diagnostic gypsic horizon (p. 46) has to be demonstrated first,
and there lies the problem for these pedons. Here again arises the
question if there are morphological clues or evidence to distinguish
geologic and pedologic gypsum.

[Silicate Clay Distribution]{.underline}

The cation exchange capacity may be as good an indicator as any in these
soils for assessing the distribution of silicate clays with depth. This
assumes that the clay mineralogy is fairly uniform with depth. The
analytical clay, as reported, is uncertain because one does not know if
the gypsum is completely removed. The 15-bar water content is suspect
because of the water of hydration associated with the gypsum. The cation
exchange capacity for Orla S78TX-389-2 supports the presence of a buried
soil as indicated by the morphologic description.

Comments From

> Dennis Nettleton and Reuben Nelson

Holloman S78TX-389-1

> Pedon either fine-silty or fine-loamy; description supports
> fine-silty. The data supports a gypsic horizon. The description does
> not support placement in a shallow family.

Orla S78TX-389-2

> Data support a gypsic horizon.

Saragosa S78TX-389-3

> Data suggest a salic horizon, but no gypsic horizon.

Saragosa S78TX-389-4

> Neither salic nor gypsic horizon present.

Dennis suggests that average rainfall from weather stations be compared
with water penetration estimated from soil morphology and water holding
properties to see if water penetration coincides.

Reuben suggests a committee be formed to address all the questions about
gypsi­ferous soils, including Gypsiorthids and gypsic family criteria.

X-ray Diffraction Data on \<2 mm Soil Material: Holloman S79TX-389-1

+---------------+------------+--------+----------+-------+-------+---+
| > 79P682 0-3  |            | Al     | QZ4      | CA3   | FD2   | G |
| > cm          |            |        |          |       |       | Y |
|               |            |        |          |       |       | 1 |
|               |            |        |          |       |       | - |
+---------------+------------+--------+----------+-------+-------+---+
| > 79P683 3-15 |            | Clcs   | GY4-5    |       |       |   |
| > cm          |            |        |          |       |       |   |
+---------------+------------+--------+----------+-------+-------+---+
| Orla          |            | > Al   | FP4      | QZ3   | CA3   |   |
| S79TX-389-2   |            |        |          |       |       |   |
+---------------+------------+--------+----------+-------+-------+---+
| > 79P7899     | > 0-13 cm  |        |          |       |       |   |
+---------------+------------+--------+----------+-------+-------+---+
| > 79P3890     | > 13-30 cm | > Clcs | GY4      | CA2   | QZ1   |   |
+---------------+------------+--------+----------+-------+-------+---+

QZ = quartz, CA = calcite, FD = Feldspar, GY = gypsum

Comments on CP83-TX271 by M. D. Mays September 24, 1985

The first set (33C84), we followed Hesse\'s Procedure and added 15 ml of
calgon with NaOH, except the first four samples did not receive the
NaOH.

On the second set (34C84), we used regular calgon solution (10 mils,
.0110 factor) and candled with filter candles. We dispersed by stirring
for 5 minutes on mechanical stirrers.

On the third set (40085), samples were treated with BaC1~2,~

candled and washed, and oven-dried overnight. The regular amount of
calgon was added and samples were allowed to set for 2 minutes before
adding 150 mls of water and stirring 5 minutes on mechanical stirrers.
They were then transferred and pipetted.

On rerun 406, samples with none or very small amounts of gypsum were
rerun to compare with samples analyzed according to a modification of
Hesse\'s Procedure.

Generally, the Hesse Procedure was somewhat cumbersome because it
required steps that were not a part of our normal operating procedure.
Also, the use of NaOH in the dispersant caused some flocculation,
therefore, it was used in only one set (33C84). Some samples appeared to
have completely flocculated but when weighed had 5-6% clay. The weights
which came out in the clays probably can be attributed to BaC1~2~ in the
suspensions. Also, observing the standard sample which received the same
treatment as the other samples in the set, the BaC1~2~ caused the clay
to partially flocculate (normally about 19%). Samples that were rerun by
the conventional method usually had significantly more clay than ones
treated by the Hesse Procedure.

> [Implications]{.underline}

1.  Some of the BaC1~2~ coating the soil particles solubilizes and is
    weighed in the clay-size fractions, causing errors in weights.

2.  BaC1~2~ causes flocculate\-- in samples that have small amounts of
    gypsum.

Note: BaCl~2~ should precipitate as BaSO~4~ and coat the gypsum (WCL
7/16/04)

3.  The Hesse Procedure does not appear to be an efficient method of
    analyzing soils for PSDA, when compared with the conventional
    method. We can wash samples with small amounts of gypsum and get
    better values and be more efficient.

GYPSUM STABILIZED BY BARIUM CHLORIDE

Modified from P. R. Hesse. 1976. Particle size distribution in gypsic
soils. Plant and Soil 44:241-247.

Reagents. Barium chloride solution: Dissolve 50 g of CaC1~2~ 2H~2~O in
50 cm3 of water. Add 20 cm^3^ of triethanolamine and dilute to one
liter. Sodium hexametaphosphate: Dissolve 40 g of sodium
hexametaphosphate and 10 g anhydrous sodium carbonate in about 600 cm^3^
of water; filter if necessary. Dilute to one liter. This solution should
be prepared freshly every week.

Procedure. Weigh 10 g of soil into a 300 ml fleaker, add 40 cm^3^ of
barium chloride solution, stopper and gently shake for 1 hour. Filter
candle until dry. Add 40 cm^3^ of distilled water, shake briefly by hand
and filter candle until dry. Repeat the water washing once more and test
with a drop of potassium chromate solution for absence of barium. Add 15
cm^3^ of sodium hexametaphosphate solution to the soil and mix with a
rubber-tipped rod. Leave for 30 minutes (do not leave longer as the
reagent slowly attacks the barium coating to form a gel of barium
complex). Stir for 2 minutes on mechanical stirrers. Decant the
suspension through a 0.05-mm sieve into a liter cylinder and wash the
sand on the sieve with distilled water until the effluent is clear.
Transfer the sand to a small, tared basin and dry in an oven at 105°C.
Weigh the sand fraction and, if required, pass it through a nest of
appropriate sieves for further subdivision. The suspension in the
cylinder is diluted to 1 liter and silt and clay determined by the
routine pipette procedure. For approximate analysis, the hydrometer
procedure can be followed but reading the hydrometer is difficult for
such small quantities in suspension, particularly if much coarse gypsum
is present in the soil.

**1338 SOIL SCI. SOC. AM. J., VOL. 46, 1982**

giving a corrected value for N~2~0 in air of 0.323 p.L•L^-^\'.

The coefficient of **variation** for measurements of N~2~0 in the range
of 0.3 to 1 µL . L\"\' was **consistently** between 6 and 9% (8
replicates) with a mean value of 7%, i.e., similar to the variability
for blank deter­minations. **Known** sources of **variability include**
serum bottle volume (±2.5%) and analytical precision (± 1%). No attempt
was made to correct for the variation in bottle volume because this
would be a difficult book-keeping task with large numbers of samples.

The sieve **procedure** was used in a two-year study of N~2~0 emissions
from organic soils in New York. A circular **vented** chamber,
**having** a wall **height** of 20 cm and a volume of 56 L, was used for
flux mea­surements. Withdrawal of a 50-mL gas sample did not cause a
detectable change in N~2~0 concentration within the chamber. Nitrous
oxide fluxes were found to be above **100** g N ha^-^\' • d^-^\', which
corresponded to an increase in N~2~0 concentration in a 20-cm high
chamber from 0.3 to 2.0 µL . L^-\'^ in 60 min, 63% of this time. The
procedure was **occasionally** used during **high** N**~2~**0 flux
periods **on cropped** mineral soils; maximum daily fluxes ranged from
200 to **600** g N ha^-^\' d^-^\'. In our experience, the sieve
procedure was **unsuitable** when N**~2~**0 fluxes were \< 10 **g** N •
ha^-^\'

d^-^\', i.e., when **concentration** changes were \< 0.2 µL • L\'\'.
Data from a study of N~2~0 emissions from mineral soils **(Duxbury** et
al., **unpublished)** can be used to illustrate the significance of the
detection limit of the sieve procedure. For example, between 1 May 1979
and 30 Apr. **1980,** N~2~0 flux from a manured corn plot was measured
on 147 d. The N~2~0 flux was \>10 g N • ha-\' • d^-^\' on 42, i.e., 29%,
of the days. The measured annual loss of N~2~0 from the site was 2.44

**kg** N • ha^-^\'. With **a** flux detection limit of 10 g N ha^-^\'
d^-^\', a value of 1.81 **kg** N • ha^-\'^ year-1 would

have been obtained. The sieve **procedure** would have provided a
reasonable estimate of N~2~0 loss from all the cropped soil sites we
have studied. It should also be useful in field **denitrification**
measurements where

C**~2~H~2\ ~**is used to block **reduction** of N**~2~**0 to N**~2~**
and N**~2~**0 emissions equal total N loss by denitrification (e.g.,

Ryden et al., 1979).

> **References**

1.  **Denmead, O. T. 1979. Chamber systems for measuring nitrous oxide
    emissions from soils in the field. Soil Sci. Soc. Am. J. 43:89-95.**

2.  **Guthrie, T. F., and J. M. Duxbury. 1978. Nitrogen mineralization
    and denitrification in organic soils. Soil Sci. Soc. Am. J.
    42:908-912.**

3.  **Hutchinson, G. L., and A. R. Mosier. 1981. Improved soil cover
    method for field measurement of nitrous oxide fluxes. Soil Sci. Soc.
    Am. J. 45:311-316.**

4.  **Mathias, A. D., A. M. Blackmer, and J. M. Bremner. 1980. A simple
    chamber technique for field measurement of emissions of nitrous
    oxide from soils. J. Environ. Qual. 9:251-256.**

5.  **Ryden, J. C., L. J. Lund, and D. D. Focht. 1978. Direct in-field
    measurement of nitrous oxide flux from soil. Soil Sci. Soc. Am. J.
    42:731-738.**

6.  **Ryden, J. C., L. J. Lund, J. Letey, and D. D. Focht. 1979. Direct
    measurement of denitrification loss from soils. II. De­velopment and
    application of field methods. Soil Sci. Soc. Am. J. 43:110-118.**

7.  **Terry, R. E., R. L. Tate III, and J. M. Duxbury. 1981. Nitrous
    oxide emissions from drained cultivated soils of South Florida. J.
    Air Pollut. Control Assoc. 31:1173-1176.**

A TECHNIQUE FOR RAPID REMOVAL OF\
GYPSUM FROM SOIL SAMPLES\'

E. D. RIVERS, C. T. HALLMARK, L. T. WEST,\
AND L. R. DREES^2^

Abstract

Removal of gypsum from soil samples is necessary to disperse soils for
particle-size analysis or clay separation for mineralogical study. A
technique utilizing the heating of gypsiferous soil overnight at 105°C
is presented. The heat treatment converts gypsum to hassanite which is
more soluble than the gypsum and the disruption of the gypsum upon
dehydration also yields bassanite particles which can easily be crushed
to provide a greater surface area. Subsequently, the time required to
remove gypsum from soil by dialysis is reduced by \>50%. Heating the
samples did not change the clay mineralogy or the cation exchange
capacity, but did result in slightly higher total and line clays and
slightly lower sand contents.

*Additional Index Words:* gypsiferous soil, soil analysis, soil
char­acterization, salt removal.

Rivers, E. D., C. T. Hallmark, L. T. West, and L. R. Drees. 1982. A
technique for rapid removal of gypsum from soil samples. Soil Sci. Soc.
Am. J. 46:1338-1340.

FLOCCULATION of clays from water suspension poses a problem for the
scientist working with soils containing gypsum and salts more soluble
than *gyp-*sum. Without a stable clay suspension it is impossible to
determine the particle-size distribution (PSD) of soils or to separate
the clay for detailed mineralogical studies (Day, 1965). Procedures for
removal of dis­solved salts from soils by solution processes include
dialysis (Grossman and Millet, 1961), centrifugation (Jackson, 1974),
and filtration (U.S. Salinity Labo­ratory Staff, 1954; Kilmer and
Alexander, 1949). Though some degree of success in removal of gypsum can
be accomplished by these methods, the relatively low solubility and slow
dissolution kinetics of gypsum place practical limits on the amounts
that can be

removed.

> This paper presents a method for the rapid removal

of gypsum from soil prior to dispersion for PSD or clay fractionation
for mineralogical studies. Guidelines are presented to indicate when
removal of gypsum from the soil sample is achieved. Evidence is given to
show that the treatment does not alter the clay minerals studied.

Materials and Methods

Soil samples from eight horizons representing five pedons and three
series were selected to give a range in gypsum and clay content. Samples
were dried at 40°C, then crushed to pass through a 2-mm sieve. Samples
used in this study, their classification, and gypsum percentages are
given in Table 1. Gypsum was determined according to the method
described by the U.S. Salinity Laboratory Staff (1954). Duplicate 10-g
samples were heated overnight at 105°C to

\' Contribution from the Texas Agric. Exp. Stn., College Station. This
research was supported in part by State funds allocated for the
acceleration of soil survey in Texas. Received 16 Apr. 1982. Approved 30
July 1982.

Research Associate, Associate Professor, and Research Asso­ciates, Dep.
of Soil & Crop Sci., Texas A&M Univ., College Sta­tion, TX 77843.

> **NOTES**

convert the gypsum to bassanite (CaSO~4~ • 1/2 H~2~0) and transferred to
dialysis bags. The dialysis bags were prepared from 30-cm sections of
dialysis tubing (3 cm in diameter). One end of the tube was closed with
a rubber band and, after placement of the sample into the bag, a 5-cm
section of glass tubing was inserted into the open end of the bag, and
the bag was secured around the tubing with a rubber band. A volume of
distilled water sufficient to make a paste of the sample was added to
each bag. Samples were gently massaged by hand to crush particles of
bassanite produced by heating the gypsum. The dialysis bags containing
samples were half-filled with distilled water and the bags were placed
in a bucket containing 15 L of distilled water having an initial
electrical conductivity (EC) of 4 x 10^-3^ dS m-\' (4 µmho/cm). A
duplicate set of 10-g samples which had not received the heat treatment
was placed in dialysis bags and dialyzed in a second bucket. Throughout
the dialysis period all samples were gently massaged by hand twice each
day (morning and afternoon), and the bags were gently shaken to
resuspend the soils. Each morning the EC of the dialysis water was
measured and recorded, then the dialysis water was replaced with fresh
distilled water. Dialysis was con­sidered completed when the sample
appeared fully dispersed and the daily EC of the dialysis water was \<
0.02 dS m^-^(20 µmho/cm for at least 2 consecutive days.

> After completion of dialysis, PSD was determined using the pipette
> method (Kilmer and Alexander, 1949). Fine clay (\<0.2 µm was
> determined by centrifugation.
>
> The clay fraction (\<2 µm) from the remaining PSD sus-pension was
> removed by repeated gravity sedimentation and syphoning, with
> distilled water used to replenish the sus-pension volume. The volume
> of clay suspension was re­duced to approximately 200 mL by flocculation
> with MgCl~2~ and subsequent decantation and centrifugation. The sands
> were then removed by wet-sieving and subfractionated by dry-sieving
> (Kilmer and Alexander, 1949).
>
> Cation exchange capacity (CEC) of the clays was deter-mined by the
> NaOAc method (U.S. Salinity Laboratory Staff, 1954). The concentration
> of clays in suspensions was determined by drying (105°C) 5-mL
> aliquots, and volumes of clay suspension adequate to provide 0.3 to
> 0.4 g of clay were used for CEC determination. Measurement of
> ex-changed Na was accomplished by flame emission with a Varian AA-475
> atomic absorption spectrophotometer.
>
> X-ray diffractograms were obtained for the clay fraction of the heated
> and unheated samples following Mg saturation. Preparation was that of
> Wilding et al. (1971) and included air-dried, ethylene glycol
> solvation, and heating to 350 and 550°C treatments of Mg-saturated
> clays.
>
> Results and Discussion *Removal of Gypsum*
>
> The EC values for the dialysis water at the end of each daily dialysis
> period for heated and unheated samples are given in Fig. 1.
> Conductivity values re-corded for day 1 were lower than day 2 as the
> former represents only a 16-h equilibration period. As ex­pected, EC of
> the dialysis water decreased with time until values of \< 0.02 dS •
> m^-^ (20 µmho/cm) were obtained and dispersion of the soils was deemed
> com­plete as evidenced when the samples remained sus­pended after the
> daily morning shaking. All of the heat-treated samples were dispersed
> by the 8th day but the untreated samples required an additional 10
> days before dispersion of all samples was accomplished.
>
> Observation from this and previous sample sets in­dicates that the EC
> of the dialysis water must be below 0.02 dS m^-^ before dispersion is
> reached. For sets
>
> **1339**

Table 1---Gypsum percentage and identification of soils used\
in the study.

Lab. no. Horizon Depth, cm Gypsum, %

Lufkin [series]{.underline} [(Vertic]{.underline} Albaqualf)

+-----------------+---------------------+--------------------+--------+
| > 514           | > 2Btky             | 122-140            | 6.0    |
+-----------------+---------------------+--------------------+--------+
| > 515           | > 2By               | 140-152            | 14.0   |
+-----------------+---------------------+--------------------+--------+
| > 521           | > 2Btkyl            | 86-102             | 10.0   |
+-----------------+---------------------+--------------------+--------+
| > 522           | > 2Btky2            | 102-130            | 18.0   |
+-----------------+---------------------+--------------------+--------+
| > 529           | > 3Btky             | 107-147            | 2.0    |
+-----------------+---------------------+--------------------+--------+
|                 | Heiden series (Odic |                    |        |
|                 | Chromustert)        |                    |        |
+-----------------+---------------------+--------------------+--------+
| > 976           | > ACb               | 158-236            | 12.0   |
+-----------------+---------------------+--------------------+--------+
| > 979           | > C3                | 498-625            | 0.2    |
+-----------------+---------------------+--------------------+--------+
|                 | Midland variant     |                    |        |
|                 | (Vedic Ochraqualf)  |                    |        |
+-----------------+---------------------+--------------------+--------+
| > 982           | > Bt4 140-160       |                    | 4.0    |
+-----------------+---------------------+--------------------+--------+

of samples representing a wide range of gypsum con-tent, dispersion is
not reached in all the samples on the same day. The time requirement
varies among sets and is most dependent on the initial gypsum content
and the ratio of total sample weight to volume of dialysis water.

The greatly decreased time requirement for removal of gypsum by dialysis
from heated compared to un­heated soil samples is attributed to the
conversion of gypsum to bassanite upon heating. This conversion was
confirmed by x-ray diffraction. The solubility of bassanite in cold
water is significantly higher than that of gypsum, i.e., 0.22 as
compared to 0.14M (Ward, 1968). Additionally, the bassanite produced by
heating gypsum crushes easily under minimum finger-tip pres­sure,
resulting in a significantly increased surface area.

*Effects of the Heat Treatment*

Particle-size distribution and CEC data for heated and unheated samples
are presented in Table 2. Analy­sis of variance for the treatment effect
showed no significant differences (95% confidence level) between heated
and unheated samples in sand subfractions, silt subfractions, total
silt, coarse clay, or CEC; however, fine and total clay were
significantly higher (99% con­fidence level) for the heated samples
compared to the unheated samples. Similarily, total sand was
signifi­cantly lower in the heated treatment group. Simple regression was
used to relate the fine and total clay

> ![](media/image2.png){width="2.0701388888888888in"
> height="1.8298611111111112in"}
>
> **0.0**
>
> **0 4 8 12**
>
> **Day**
>
> Ng. 1---Electrical conductivity of dialysis water for each daily
> dialysis period.
>
> **1340 SOIL SCI. SOC. AM. J., VOL. *46,* 1982**

Table 2-Particle-size distribution and CEC of heated\
and unheated samples.

Total

Lab 2-0.05 0.05- clay

no. mm 0.002mm \<0.2pm \<2pm CEC

+-----+------------+-----------+--------------+-------+---------------+
|     |            | Percent   |              |       | cmol (NH. +   |
|     |            | of \<     |              |       | kg-\',        |
|     |            | 2-mm      |              |       |               |
|     |            | fraction  |              |       | meq/100 g     |
+-----+------------+-----------+--------------+-------+---------------+
|     |            |           |              |       |               |
+-----+------------+-----------+--------------+-------+---------------+
|     |            |           |              |       |               |
+-----+------------+-----------+--------------+-------+---------------+
|     |            |           | Heated       |       |               |
+-----+------------+-----------+--------------+-------+---------------+
| 514 | 26.8       | 43.2      | 23.2         | 30.0  | 74.4          |
+-----+------------+-----------+--------------+-------+---------------+
| 515 | 22.3       | 50.4      | 19.2         | 27.3  | 73.6          |
+-----+------------+-----------+--------------+-------+---------------+
| 521 | 20.1       | 46.2      | 25.9         | 33.7  | 78.6          |
+-----+------------+-----------+--------------+-------+---------------+
| 522 | 10.8       | 58.6      | 21.7         | 30.6  | 77.4          |
+-----+------------+-----------+--------------+-------+---------------+
| 529 | 14.8       | 52.2      | 23.9         | 33.0  | 83.2          |
+-----+------------+-----------+--------------+-------+---------------+
| 976 | 2.0        | 50.1      | 25.7         | 47.9  | 64.0          |
+-----+------------+-----------+--------------+-------+---------------+
| 979 | 2.3        | 39.2      | 18.4         | 58.5  | 36.9          |
+-----+------------+-----------+--------------+-------+---------------+
| 982 | 13.3       | 39.8      | 35.1         | 46.9  | 65.5          |
|     |            |           |              |       |               |
|     |            |           | Unheated     |       |               |
+-----+------------+-----------+--------------+-------+---------------+
| 514 | 28.4       | 42.8      | 21.8         | 28.8  | 74.9          |
+-----+------------+-----------+--------------+-------+---------------+
| 515 | 23.3       | 49.8      | 18.0         | 26.9  | 76.3          |
+-----+------------+-----------+--------------+-------+---------------+
| 521 | 20.8       | 46.9      | 25.6         | 32.3  | 74.8          |
+-----+------------+-----------+--------------+-------+---------------+
| 522 | 11.0       | 59.4      | 20.8         | 29.6  | 74.3          |
+-----+------------+-----------+--------------+-------+---------------+
| 529 | 15.7       | 51.9      | 23.3         | 32.3  | 80.6          |
+-----+------------+-----------+--------------+-------+---------------+
| 976 | 2.7        | 50.4      | 25.5         | 46.9  | 64.9          |
+-----+------------+-----------+--------------+-------+---------------+
| 979 | 4.3        | 37.8      | 18.3         | 57.9  | 38.3          |
+-----+------------+-----------+--------------+-------+---------------+
| 982 | 13.4       | 40.7      | 34.6         | 45.9  | 63.1          |
+-----+------------+-----------+--------------+-------+---------------+

> *of* unheated to heated samples. Resulting equations were

heated fine clay = 1.29 *+ 0.973* (unheated fine clay),\
*(R*^2^ *= 0.992),*

> and

heated total clay = 1.08 *+ 0.995* (unheated total clay), *(R*^2^ *=
0.999).*

> Data suggest that the increase in fine and total clay is predominately
> from the sand fraction. This increase in fine and total clay may be
> due to more complete dispersion in the heated samples, and for most
> pur­poses, the differences are not sufficiently great to warrant
> concern.
>
> Comparison *of* x-ray diffractograms for Mg-satu­rated clays from
> heated and unheated samples (not shown) indicated that there *is* no
> observable treatment effect. The comparison evaluated relative height,
> *po­*sition, and symmetry *of* peaks for Mg-saturated air-dried,
> ethylene glycol expanded, and heating to *350* and *550°C*
> preparations. Smectite, illite, kaolinite, quartz, feldspars, and
> calcite were identified in the clay fractions studied. Caution in
> interpreting diffrac­tograms should be exercised with other clay
> minerals for which the heat treatment effect has not been evaluated.
>
> Conclusions
>
> The removal *of* gypsum from *soil* samples prior to PSD or clay
> separations for mineralogical studies *is* greatly facilitated by
> heating the sample overnight at 105°C. Heating transforms the gypsum
> to bassanite which results in a significant reduction in time required
> to solubilize and remove the gypsum. Although the heat treatment
> increases fine and total clay and de-creases total sand, these
> differences are so small that they do not warrant concern. Further,
> the heat treat­ment does not affect the x-ray diffraction properties
> *of* smectite, illite, kaolinite, quartz, feldspar, or calcite

present in this study; however, this heat treatment may affect minerals
in soils with different clay mineral suites.

References

1.  Day, P. R. 1965. Particle fractionation and particle-size analysis.

> *In C. A.* Black et al. (ed.) Methods of soil analysis, Part 1.
>
> Agronomy 9:545-567. Am Soc. of Agron., Madison, Wis.

2.  Grossman, R. B., and J. L. Millet. 1961. Carbonate removal

> from soils by a modification of the acetate buffer method. Soil
>
> Sci. Soc. Am. Proc. 25:325-326.

3.  Jackson, M. L. 1974. Soil chemical analysis-advanced course (2nd
    ed.) Published by the Author, Dep. of Soil Science, Univ. of
    Wisconsin, Madison.

4.  Kilmer, V. J., and L. T. Alexander. 1949. Methods of making
    mechanical analysis of soils. Soil Sci. 68:15-24.

5.  U.S. Salinity Laboratory Staff. 1954. Diagnosis and improve­ment of
    saline and alkali soils. Agric. Handb. no. 60, USDA. L. A. Richards
    (ed.) U.S. Government Printing Office, Wash­ington, DC.

6.  Ward, R. C. (ed.) 1968. Handbook of chemistry and physics (4th. ed.)
    The Chemical Rubber Co., Cleveland, Ohio.

7.  Wilding, L. P., L. R. Drees, N. E. Smeck, and G. F. Hall. 1971.
    Mineral and elemental composition of Wisconsin-age till deposits in
    West Central Ohio. In Till/A Symposium. Ohio State Uni­versity, 1969.
    Ohio State University Press, Columbus.

**MODIFIED SOXHLET EXTRACTOR FOR\
PEDOLOGIC STUDIES\'\
A. A. SOBEK, M. A. BAMBENEK, AND D. MEYER^2^\
Abstract**

**The soxhlet apparatus has been used in the laboratory to stimulate
geochemical weathering; however, the high extraction temperatures
required in the soxhlet do not represent a realistic simulation of the
weathering environment. A modified design of the original soxhlet did
not eliminate the problems of extraction temperature or inaccurate
volumes of solvent passing through the sample. These problems were
solved by moving the extraction chamber away from the upward path of the
relluxing solvent. Extraction temperature differences (approx­imately
52°C) were responsible for higher concentrations of leachate metal in
the original soxhlet leachate when a minesoil sample was weathered. This
modification permits exact volumes of solvent to be passed through the
sample, as well as a reduction In extraction tem­perature that would
allow study of the role of bacteria in the weath­ering process.**

***Additional Index Words:* laboratory weathering, pedogenic simu­lation,
minesoils.**

**Sobek, A. A., M. A. Bambenek, and D. Meyer. 1982. Modified soxhlet
extractor for pedologic studies. Soil Sci. Soc. Am. J. 46:1340-1342.**

**THE SOXHLET EXTRACTOR was used by Pedro (1961) as a means *of*
leaching crystalline rocks. Since this initial report, numerous other
researchers have**

**\' Contribution from the Land Reclamation Program, Argonne National
Laboratory, 9700 South Cass Avenue, Argonne, IL 60439. This work was
sponsored by the U.S. Dep. of Energy under con-tract W-31-109-ENG-38.
Received 2 Mar. 1982. Approved 26 July 1982.**

**^2^ Assistant Environmental Scientist, Argonne National Labora­tory;
Professor of Chemistry, Saint Mary\'s College, Notre Dame, Ind.; and
Undergraduate Research Participant at Argonne National Laboratory from
the Dep. of Chemistry, Trinity Christian College, Palos Heights, Ill.**