A Deep Alteration and Oxidation Profile in a Shallow Clay Aquitard: Example of the Tégulines Clay, East Paris Basin, France

Figure 4

(a) Calcite bioclast filled by framboidal pyrite which is partially oxidized (AUB1010-6.63 m) (BSE image); (b) residual porosity in bioclast filled by microsparite (AUB1010-11.32 m) (transmitted light); (c) euhedral grain of dolomite (BSE image) (AUB1010-6.63 m); (d) grain of Fe-bearing dolomite partially dissolved and surrounded by iron hydroxides (BSE image) (AUB1010-4.80 m); (e) cluster of siderite grains (AUB1010-16.1 m); (f) isolated siderite grain enclosed in diagenetic phosphate nodule (AUB131-38 m); (g) electron microprobe analyses of carbonates in thin sections of rock.

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