Iron Content of Modern Deposits in the Sonoran Desert: A Contribution to the Origin of Red Beds

Walker, Theodore R.; Honea, Russell M.

doi:10.1130/0016-7606(1969)80[535:icomdi]2.0.co;2

Cited by 58 publications

(28 citation statements)

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“…The dithionite process is widely used to extract secondary (weathering) iron oxides, mainly hematite and goethite (e.g. Torrent et al, 1980;Torrent and Cabedo, 1986;Walker and Honea, 1969;White and Walden, 1994), although the technique has been shown to remove significant amounts of magnetite as well (Liu et al, 1995;van Oorschot and Dekkers, 1999).…”

Section: Methodsmentioning

confidence: 98%

Mapping the geochemistry of the northern Rub' Al Khali using multispectral remote sensing techniques

White

Goudie

Parker

et al. 2001

Earth Surf Processes Landf

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Spatial variations in sand sea geochemistry relate to mixing of different sediment sources and to variations in weathering. Due to problems of accessibility, adequate spatial coverage cannot be achieved using field surveys alone. However, maps of geochemical composition produced from remotely sensed data can be calibrated against limited field data and the results extrapolated over large, inaccessible areas. This technique is applied to part of the Rub' Al Khali in the northern United Arab Emirates. Trend surface analysis of the results suggests that the sand sea at this location can be modelled as an east-west mixing zone of two spectral components: terrestrial reddened quartz sands and marine carbonate sands. Optical dating of these sediments suggests that dune emplacement occurred rapidly around 10 ka BP, when sea level was rising rapidly. The spatial distribution of mineralogical components suggests that this phase of dune emplacement resulted from coastal dune sands being driven inland during marine transgression, thereby becoming mixed with rubified terrestrial sands.

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Section: Methodsmentioning

confidence: 98%

Mapping the geochemistry of the northern Rub' Al Khali using multispectral remote sensing techniques

White

Goudie

Parker

et al. 2001

Earth Surf Processes Landf

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“…Alteration of the fan deposits by weathering also occurs immediately below the fan surface. Unstable grains such as ferromagnesium minerals or feldspars alter to finer-sized products through hydrolysis and oxidation (Walker 1967, Walker andHonea 1969). Clay-sized particles also are mechani- cally added to sediment pores as the result of transportation by infiltrating water (Walker et al 1978).…”

Section: Weathering and Soil Developmentmentioning

confidence: 99%

Alluvial Fan Processes and Forms

Blair¹,

McPherson²

1994

Geomorphology of Desert Environments

194

266

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“…This has been fully utilized in the electron microprobe (EM) which allows quantitative chemical analyses to be made of individual minerals using a fully focussed 10-0.5 #m electron beam. The EM is particularly well suited to the analysis of mineral transformation (Velde 1977;Walker et al 1978;Boles 1981). or of zonation in cementing minerals (Keighin & Fouch 1981).…”

Section: Electron-microprobe Analysismentioning

confidence: 99%

Clastic diagenesis

Burley

Kantorowicz

Waugh³

1985

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Summary Diagenesis is the sum of those processes by which originally sedimentary clastic assemblages attempt to reach equilibrium with their environments. The subject has rapidly evolved, over the last 20 years, after several decades of routine petrographical analysis, to become a discipline of sophisticated analytical geochemistry. This progression may be traced through the evolution of depositional facies models, the growth of theoretical geochemistry, and the development and application of quantitative analytical techniques. Consequently, the study of diagenesis today involves the integration of data gathered from a range of interrelated disciplines. The publication in recent years of such integrated studies, particularly from the Texas Gulf Coast of the U.S.A., has led to a number of wide ranging models being established. These models allow an interpretation of the sequence of authigenic minerals in terms of their relationship to the depositional environment or surface chemistry (eogenesis), burial or subsurface conditions (mesogenesis) and weathering or reexposure to surface conditions (telogenesis). More specifically, once the pre-depositional controls on diagenesis have been established, it is possible to relate the inferred eogenetic mineral assemblages to exact geochemical sedimentary environments. Sedimentary mineral assemblages chemically are characterized by relative instability and so tend to interact with interstitial pore waters. Thus, in non-marine environments, mineral authigenesis may reflect arid-oxidizing, or wet-reducing pore-water conditions, and in the marine environment, either oxidizing or reducing pore waters. During mesogenesis different processes become important. Elevated temperatures add energy to the reacting system, lowering reaction barriers and increasing reaction rates. Furthermore, widespread pore fluid migration at depth, transporting large quantities of solute, is likely to impart major, regional diagenetic changes to sediments. That there is a remarkable degree of consistency in deep burial settings suggests that depth-related processes conform to a predictable pattern. Additional geochemical instability is introduced into the diagenetic system during uplift and exposure to the telogenetic realm. Minerals formed during burial, at elevated temperatures and pressures, and from concentrated formation waters, may become unstable in oxidizing, meteoric waters. Diagenetic research requires the complete dissection of sedimentary rocks and, subsequently, the quantitative chemical and mineralogical analysis of their individual components. Such an approach to diagenetic studies, when related to an assessment of their paragenesis, may eventually lead to a predictive, integrated model for the evolution of sedimentary clastic rocks.

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Iron Content of Modern Deposits in the Sonoran Desert: A Contribution to the Origin of Red Beds

Cited by 58 publications

References 0 publications

Mapping the geochemistry of the northern Rub' Al Khali using multispectral remote sensing techniques

Mapping the geochemistry of the northern Rub' Al Khali using multispectral remote sensing techniques

Alluvial Fan Processes and Forms

Clastic diagenesis

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