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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Genesis of soils derived from the Kaibab Formation of the Colorado Plateau, Arizona.

Levine, Steven Joel. January 1987 (has links)
Important pedogenic processes of soils formed on dolomitic limestones are affected by the degree of in-situ weathering of the underlying bedrock. Decalcification and silicate clay illuviation of Haplustalfs and Calciustolls of the Colorado Plateau in northwestern Arizona results from the establishment of effective porosity in the parent rock. The underlying carbonate strata, the Kaibab Formation, are a complex limestone-dolomite-chert marine sediment of Permian age. Diagenetic processes have modified the initial porosity present at the time the sediment was deposited. Pleistocene meteoric waters, percolating downward, have resulted in the solutioning and partial removal of the calcium carbonate and the establishment of a porous dolomitic framework. Under these conditions, soils forming in residuum are able to decalcify and to form argillic horizons. However, in more resistant limestones, compaction during burial has resulted in a nonporous micrite which retards calcite removal by meteoric waters. Under these conditions, soil profiles maintain a high CaCO₃ content and silicate clay illuviation does not occur. Micaceous clay minerals of residual origin are converted to montmorillonite in the Alfisols. A probable sequence of events for this transformation to occur is: (1) the removal of calcite from the dolomitic limestone bedrock and the formation of a dolomitic framework, (2) the slow dissolution of dolomite and release of Mg⁺⁺ into solution, (3) the incorporation of Mg⁺⁺ into the octahedral layer of the mica and the release of K⁺ from the mica interlayer position, and (4) the illuviation of montmorillonite to form the argillic horizon. Eolian dust is also important to soil genesis on the Colorado Plateau. In particular, quartz in the coarse silt fraction (31-44 um) and quartz and biotite in the very fine and fine silt fractions (2.0-16 um). Two alluvial soils of Pleistocene age shows important morphological differences. Thick carbonate accumulations of ground water origin are present in the older soil. The effects of the Pleistocene-Holocene climatic change on this area are: (1) modification of karst topographic features, (2) aggradation of valley bottoms, and (3) the influence of Holocene slope wash Pleistocene soil properties such as calcite, dolomite and organic matter.
32

THE PHYSICAL, CHEMICAL, AND SPECTRAL CHARACTERISTICS OF SOILS AT PAGE RANCH INTERNATIONAL CENTER, PINAL COUNTY, ARIZONA.

Ghenniwa, Abdelgiawad Mohamed. January 1985 (has links)
No description available.
33

The interaction of parent material and eolian debris on the formation of soils in the Silverbell Desert Biome of Arizona

Rosenthal, Randi Helaine, 1961- January 1987 (has links)
The objective of this study was to determine whether the properties of four soils of the Silverbell Desert Biome could be attributed solely to the parent material or alternately reflect the nature of contributions, if any, from eolian dust. The Anklam, Lajitas and Chimenea soils, classified as fine-loamy, mixed, thermic Lithic Haplargids and the Greyeagle (coarse-loamy, mixed, thermic, Lithic Torriorthent) soil formed an andesite, basalt, granite and basalt, respectively. They occur on gently sloping, stable terrain in Pima County, Arizona. The four soils were studied through field descriptions, particle size analysis, mineralogical analyses of light and heavy sand fractions and clay mineral identification. The light mineral fraction of all four soils is directly affected by the parent material and is influenced much less, if at all by eolian activities due to the larger particle sizes. It is concluded that the genesis of soils was influenced by both the underlying rock and the input of eolian particulates. (Abstract shortened with permission of author.)
34

Soil characterization, classification, and biomass accumulation in the Otter Creek Wilderness

Schnably, Jamie. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vii, 137 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 71-76).
35

Late quaternary deposition and pedogenesis on the Aguila Mountains piedmont, southwestern Arizona

McHargue, Lanny Ray January 1981 (has links)
No description available.
36

A study on the soils containing amorphous materials in the island of Hawaii

Houng, Kun-Huang January 1964 (has links)
Typescript. / Thesis--University of Hawaii, 1964. / Bibliography: leaves 176-187. / xiii, 187 leaves ill. (part mounted), tables
37

A genetic study of the gray hydromorphic soils of the Hawaiian Islands

Hussain, Md. Sultan January 1967 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1967. / Bibliography: leaves 228-238. / xviii, 252 leaves maps, graphs, tables
38

The character and genesis of pedogenic calcrete in southern Australia

Grevenitz, Paul. January 2006 (has links)
Thesis (Ph.D.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: p. 129-148.
39

Late-glacial through holocene stratigraphy and lake-level record of Rangely Lake, western Maine /

Metcalfe, Elisabet Joan, January 2007 (has links)
Thesis (M.S.) in Earth Sciences--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 86-93).
40

Alluvial stratigraphy and soil formation at Cox Ranch Pueblo, New Mexico

Vanbuskirk, Stephanie, January 2004 (has links) (PDF)
Thesis (M.A. in anthropology)--Washington State University. / Includes bibliographical references.

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