Lateritic soils

LaBrecque JJ (1990) The comparison of the results of two independent intercomparison studies (BAK-i and SLB-i) ftom the same bulk material of a lateritic soil. Fresenius J Anal Chem 338 498-500. 

Chairidchai P., Ritchie G.S.P. Zinc absorption by a lateritic soil in the presence of organic ligands. Soil Sci Soc Am J 1990 54 1242-1248. 

Element Laterites from basalts (n SI) Accumulation factor with respect to parent rock Lateritic soils of Western Australia (n 39) Range of Correlation coefficient with concentration Fe concentration ... 

Anand, R.R. Gilkes, R.J. (1987a) Iron oxides in laterite soils from Western Australia. J. Soil Sci. 38 607-622... 

M. (1992) Moisture effects on visible spectral characteristics of lateritic soils. Soil Sci. 153 129-141... 

If sorption is followed for long periods—i.e., weeks—it is found that the sorption increases significantly for organic soils but not for the lateritic soil 3. Table VI compares the results for soil Qi (32% organic matter) with soil 3 (0.3% organic matter). A number of test tubes containing 2.0 ml. of 1 p.p.m. C"14-labeled 4-amino-3,5,6-trichloropicolinic... 

Temple at Angkor Wat in Cambodia built with thatched lateritic soil. (Photograph courtesy of Barbara and James Franch.)... 

Some silicate minerals are also formed in a similar manner. The process is very slow, slower than even carbonate formation, because of the very low solubility of silicate minerals. In clay minerals, or in lateritic soils, silicates dissolve very slowly to form an intermediate product, silicic acid (H4Si04), which subsequently will react with other sparsely soluble compounds and form silicate bonding phases. Thus, a dissolution-precipitation process seems to be crucial to forming some silicate minerals. 

In hardened lateritic soils, the binding phase is so small that it cannot be isolated and identified. However, needle-shaped crystalhne growth was found in silicate-bonded red mud [22]. Such direct evidence is not available for natural soils, but the fact that soils harden when they are rich in alumina after wetting and drying cycles suggests that the dissolution-precipitation phenomenon controls hardening of these lateritic sods. 

In spite of this limitation, the method is very useful, because it provides a means of forming a ceramic of one of the most common and inexpensive oxides. As discussed before, iron oxide is a component of lateritic soils and red mud, high-volume iron mine tailings, and machining swarfs. Thus, useful products of several mineral waste streams can be formed by the process described in this chapter. Development of ceramics using red mud and swarfs is discussed in Chapter 14. 

Viers J. and Wasserburg G. J. (2002) Behavior of Sm and Nd in a lateritic soil profile. Geochim. Cosmochim. Acta (in press). 

Braucher, R., Bourles, D.L., Brown, E.T., Colin, F., Muller, J.-P., Braun, J.-J., Delaune, M., Edou Minko, A., Lescouet, C., Raisbeck, G.M. Yiou. F. (2000) Application of in stiM-produced cosmogenic 10Be and 26A1 to the study of lateritic soil development in tropical forest theory and examples from Cameroon and Gabon. Chemical Geology 170, 95-111. 

Debaveye, J. de Dapper, M. (1987) Laterite, soil and landform development in Kedah, Peninsular Malaysia. Zeitschrift filr Geomorphologie N.F., Supplement Band 64, 145-161. 

Prescott, J.A. Pendleton, R.L. (1952) Laterite and Lateritic Soils. Technical Communication 47. Farnham Royal Commonwealth Bureau of Soil Science. 

Only the northernmost pan of Australia (Cape York, Kimberley and the Arnhem Land peninsula) falls in the belt of equatorial monsoons. It is characterized by Tropical Rain Forest, Afforested Savanna and Light Forest ecosystems on Ferrasols and Nitosols, at places, lateritized soils. The sonthern fringe of the continent, its southwestern and sonlheastem parts, and also the island of Tasmania fall in the subtropical zone in the belt of westerly cyclonic cnrrents of air masses. They experience winter in the Sonthern Hemisphere. A dry snmmer and winter rains impart the characteristics of a Mediterranean snbtropical climate and determine the appearance of Dry Forest and Brnsh ecosystems on different Cambisols. 

It is often claimed that, sodium hexametaphosphate is not effective in dispersing lateritic soils and soils containing much colloidal iron or aluminium oxides. Better dispersion may be obtained with sodium hydroxide, with ammonium carbonate and sodium hydroxide. 

Production rates by muons. Experimental determinations of cosmogenic nuclide production by muons are scarce, and for noble gases even absent. In a depth profile from lateritic soil in the Congo, Brown et al. (1995a) were able to discern the muon-produced component of e in quartz and constrain its contribution at the surface (300 m altitude)... 

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