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Beneath a layer of artificially deposited peat debris, an eluvial E horizon and thin iron pan (Bsm) has developed in the upper part of the Ap horizon of a brown podzolic soil (Haplorthod) near Castletownbere, Ireland. The thickness of the E horizon and the depth of the pan are directly related to the thickness of the layer of peat debris.The original soil (Haplorthod) was strongly podzolized with a significant accumulation of organic carbon, iron and aluminium in the spodic Bs. The iron pan of the upper sequum, on the other hand, is rich in iron. This iron pan seems to have developed as a result of reduction of iron in the E horizon, transport of divalent Fp2+ cations and precipitation in the Bsm as Fe2(0H)3, after the peat layer was deposited. We conclude that podzolization and iron pan development were fundamentally different processes.The study suggests a fundamental change in the iron pan-blanket peat development sequence previously postulated by palaeoenvironmentalists in Ireland.

Summary The concept of ferrolysis as defined in the 1970s by Brinkman and co‐workers is mentioned in the recent literature as a dominant process to explain clay disintegration, interlayering of clay minerals, and strong texture contrast of duplex soils, in which bleaching and mottling are predominant features. Ferrolysis is based on biochemical reduction of free iron(III) oxides to Fe2+ and re‐oxidation of Fe2+ during alternating reducing and oxidizing conditions in the soil. The acidity produced during the oxidation is assumed to release cations from silicates which results in the destruction of clay minerals.  A detailed analysis of data from chemical analyses, laboratory experiments, and mineralogical and micromorphological investigations, which have been considered to sustain the ferrolysis theory, has been carried out. Some soils in Belgium and France, which have been considered to be formed mainly by ferrolysis, show strong textural contrast or albeluvic features. It has been shown that the development of these soils is due to clay translocation rather than to clay destruction by ferrolysis. Fine quartz and chlorite, assumed to be secondary minerals formed during ferrolysis, are more likely formed by disintegration of larger quartz and chlorite particles.

The evolution of glauconite in an imperfectly drained glauconiferous profile with texture B horizon in the Antwerp Campine (Belgium) has been studied by using different techniques (DTA, TGA, XRD and chemical analysis). It has been found that (1) the glauconite sand grains are mechanically broken down into clay particles without alteration of the mineralogical structure, (2) the clay sue glauconite is gradually transformed into mica-nontronite and nontronite, and even partly broken down releasing high amounts of amorphous iron, and (3) glauconite clay and especially its transformation products have migrated selectively out of the upper part and their accumulation downward has formed a strongly pronounced argillic horizon.Die Urnwandlung von Glamkonit in naaaen, mudigen W e n in den belgischen Kempen Die Urnwandlung des Glaukonit in eincm nassen, glaukonithaltigen Prof3 mit Bt-Horizont in den Antwerpener Kempen (Belgien) wurde mit Hilfe verschiedener Methoden untersucht (DTA, TGA, XRD und chemische Analyse). Dabei zeigte sich, (1) daD die Glaukonit-Sandkbmer mechanisch in Tonteilchen zerteilt werden, ohne daO ihre mineralogische Struktur sich andert; (2) da6 der Glaukonit der Tonfraktion langsam in Glimmer-Nontronite und Nontronit umgebildet wird; zumindest wird er teilweise abgebaut, wobei gro6e Mengen amorphen Eisens frei werden; (3) daO glaukonithaltiger Ton und besonders die aus ihm gebildeten Produkte selektiv aus dem obersten Horizont auswandern und sich tiefer anreichem, infolgedessen sich ein starker ,,argillic" Bt-Horizont ausbildet.

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