The approach of cement stratigraphy consists of establishing the chronological order of cementation phases with the help of cement morphologies and signals of the cathodoluminescence. For each phase of their diagenetic sequences, the authors assume only some of these factors of luminescence. Zonations summarize a complexity of possible interstitial water evolution, and the diagenesis successive steps have to be identified to permit the elaboration of diagenetic sequences that can be used for establishing a lithification model (Meyers 1991). These factors also trigger the following five different zonations recognized in cathodoluminescence of carbonates: concentric, oscillatory, sectorial, mottled and homogeneous (Reeder 1991). 2000), but many other factors are to be considered, such as: salinity changes, concentrations of metal ions, Ca 2+ activity, kinetics of crystal growth, sources of organic matter and clay minerals, temporal and spatial variations of pore fluid chemistry, and diagenetic processes (Machel and Burton 1991 Machel 1999). Calcite luminescence thus often reflects the eH/pH evolution of the interstitial fluids (Machel 1985 Pagel et al. The reduction of Mn 3/4+ can take place in sub-oxic waters, reduction of Fe 3+ in waters of even lower redox potential, sometimes close to anoxia (Plunkett 1997). 2003), the Fe 2+/Mn 2+ ratio is supposed to control the intensity of luminescence in carbonate. Although the role of iron still needs further investigation (Cazenave et al. As little as 10–20 ppm Mn 2+ and 30–35 ppm Fe 2+ in solid solution are sufficient to produce or quench the luminescence. Fe 3+ and Mn 3/4+ have to be reduced to divalent state to substitute calcium. Luminescence of calcite in sedimentary rocks is activated by the incorporation of manganese in its crystal lattice and inhibited by iron. The incorporation of luminescence inhibiting and activating elements in carbonate lattices reflects the pore fluids evolution of the system, and gives important information on the diagenetic environment. The signals of cathodoluminescence are used to observe zonations in crystals and permit, in the study of cements, to determine the various steps of diagenesis (Amieux 1982 Richter et al. This result is sustained by petrological and geochemical analyses such as alizarine–ferricyanure stained thin sections, X microfluorescence mapping of elements, and microthermometry of fluid inclusions. The final statistical similarity between the two outcrops reaches an index of R = 0.78. Their diagenetic sequences recorded in cathodoluminescent cements are presented and being compared. A case study from two Upper Kimmeridgian Mount Salève outcrops (France) illustrates this methodology. Cementation events and diagenetic chronologies can thus be quickly correlated without the support of a full chronology, the model normally established on cement morphologies, petrological analyses and cathodoluminescence zonation sequences. Based on the statistical comparison of signals extracted from the red spectrum emission of cathodoluminescence digital images, it gives via crosscorrelation a measure of similarity (values scaled from minimum −1 to maximum 1) between two cathodoluminescence facies. This article exposes a methodology of image analysis that facilitates the spatial correlation of diagenetic events in carbonate rocks. Regional cement stratigraphy allows correlations and understanding of the petrological heterogeneities in reservoirs and aquifers, but is a long and rigorous approach. Cement stratigraphy of carbonates aims to establish the chronology of processes involved in the rock diagenesis.
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