Paris Basin

Oil A (Paris Basin) - from a marine origin which is already altered and will not be further transformed. 

Their results show that the redox couples in a sample generally failed to achieve equilibrium with each other. For a given sample, the Nernst Eh values calculated for different redox couples varied over a broad range, by as much as 1000 mV. If the couples had been close to redox equilibrium, they would have yielded Nernst Eh values similar to each other. In addition, the authors could find little relationship between the Nernst values and Eh measured by platinum electrode. Criaud et al. (1989) computed similarly discordant Nernst Eh values for low temperature geothermal fluids from the Paris basin. 

Criaud, A., C. Fouillac and B. Marty, 1989, Low enthalpy geothermal fluids from the Paris basin, 2 - oxidation-reduction state and consequences for the prediction of corrosion and sulfide scaling. Geothermics 18, 711-727. 

Fouillac, C., Fouillac, A. M. Criaud, A. 1990. Sulphur and oxygen isotopes of dissolved sulphur species in formation waters from the Dogger geothermal aquifer, Paris Basin, France. Applied Geochemistry, 5, 415-427. 

Rojas, J., Menjos, A., Martin, J. C., Criaud, A. Fouillac, C. 1987. Development and exploitation of low enthalpy geothermal systems example of the Dogger in the Paris Basin, France. In Proceedings of the 12th Workshop on Geothermal Reservoir Engineering, Stanford University, 203 -212. 

Figure kk. Temperature-depth plot for the sedimentary sequences in which a major change in the organic matter occurs. V, LA = Ventura and Los Angeles basins, Philippi (1965) BP = Paris basin L = Logbaba core ... 

The variation in the TR with depth for three other natural maturity sequences (Mahakam Delta, Paris Basin, North Sea) is plotted with that for the Monterey Fm. in Figure 4. While the geothermal histories of these sequences are different, there is in each case a strong relationship between maximum temperature experienced by the sample and depth. Depth is therefore used here as a common maturity axis for comparative purposes. Each of these sequences show a slight but significant decrease in this ratio with increasing depth. The extent of the decrease is, however, less dramatic than that for the Monterey sequence due mainly to their lower initial organic sulfur contents. 

Figure 4. Variation in the thiophene ratio (TR) with depth for samples from four sedimentary sequences. For samples from the Paris Basin, maximum depths of burial from Mackenzie et al (23) were used.

Figure 6. Ternary plots showing the variation in relative abundances of 2,3-dimethylthiophene, n-non-l-ene and 1,2-dimethylbenzene with depth (meters) for samples from the four sedimentary sequences. Maximum depths of burial are given for samples from the Paris Basin.

Figure 11. Variation in the ratio of eCj-C alkylbenzo[fr]thiophenes (Peaks 16-18, Figs. 10 and 13) relative to eC1-C3 alkylthiophenes (Peaks 2-14, Figs. 10 and 13) with respect to depth or temperature of artificial maturation. Maximum depths of burial are used for samples from the Paris Basin. Values determined from peak height data, corrected for quadratic response of FPD. Continued on next page.

The trends described above can, to a certain extent, also be discerned in the Paris Basin maturity sequence (see Figures 11 and 12) but facies variations, which have been previously noted for these samples (62). also appear to significantly influence the distributions. 

Marty, B., Torgersen, T., Meynier, V, O Nions, R. K., de Marsily, C. (1993) Helium isotope fluxes and groundwater ages in the Dogger Aquifer, Paris Basin. Water Resources Res., 29(4), 1025-35. 

Table 11.6 Hydrological and Isotopic Data of Groundwaters in the Paris Basin...

The Paris basin study warrants a closer look. In Fig. 11.11 it is seen that the spacing between studied wells was several kilometers near Paris, tens of kilometers in the periphery, and almost 100 km between the southern wells and the central ones. The conclusion that may be drawn is that the... 

Fig. 11.9 Location map of wells studied in the Paris basin well numbers as in Table 11.6. (From Evin and Vuillaume, 1970.)...

These examples demonstrate the importance of tritium measurements in every 14C study. In the Paris basin a relatively large number of tritium measurements were done and, except for the four samples mentioned, no tritium was detected in the samples assigned to the confined aquifer. 

Fig. 11.12 13C and tritium as a function of 14C in the Albian aquifer of the Paris basin (Table 11.6). x, free water table dots, confined. Initial 14C value is 58-80 pmc (see text). 

Exercise 11.5 Based on the data provided in Table 11.6 for groundwaters in the Paris basin, give your expert opinion on the hydrology of well 1, Parly-Chenons. 

The Paris Basin, in which Jurassic aquifers are encountered at depths of 1600 1850 m (Marty et al., 1988)... 

The Paris Basin, situated in northeastern and central France, is an intracratonic depression with... 

Figure 3 Simplified diagram of the Paris Basin (a) locations of the sampled areas central square—samples from the Paris region (Meynier and Marty, 1990) (b) central square enlarged and (c) simplified diagram of the main aquifers in the Paris Basin—arrows show exchanges of water (entering and leaving) between the aquifers (Castro et al, 1998b) (reproduced by permission of American Geophysical Union from Water Resour. Res. 1998, 34, 2443-2467).

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