Haute-Marne Underground Research Laboratory

Physics and Chemistry of the Earth 36 (2011) 1450–1468

Contents lists available at ScienceDirect

Physics and Chemistry of the Earth journal homepage: www.elsevier.com/locate/pce

Water flow in the Oxfordian and Dogger limestone around the Meuse/Haute-Marne Underground Research Laboratory Y. Linard a,⇑, A. Vinsot a, B. Vincent a,b, J. Delay a, S. Wechner c, R. De La Vaissière a, E. Scholz a, B. Garry a, M. Lundy a, M. Cruchaudet a, S. Dewonck a, G. Vigneron a a b c

Andra, Centre de Meuse/Haute Marne, 55290 Bure, France Cambridge Carbonates Ltd., 14 rue du Mont, 52320 Marbéville, France Hydroisotop GmbH, Woelkestr. 9, D-85301 Schweitenkirchen, Germany

a r t i c l e

i n f o

Article history: Available online 3 August 2011 Keywords: Deep borehole Groundwater sampling Geochemistry Oxfordian and Dogger limestone formations

a b s t r a c t Within its scientific program devoted to the feasibility of a high level radioactive waste facility in the Callovo-Oxfordian argillaceous rock (COx) of the eastern Paris Basin, Andra has conducted an extensive characterization of the Oxfordian and Dogger limestone formations above and below the COx. More than 25 wells were dedicated to the hydrogeological and geochemical characterization of the Oxfordian and Dogger limestones over a 400 km2 sector. An original strategy was developed to obtain field hydrogeological measurements and representative formation water samples in these wells. An extensive 3D set of field data and water compositions were obtained over 15 years. The geochemical and isotopic data indicate a meteoric origin for the Oxfordian and Dogger limestone waters. The geological observations revealed a clay rich level horizontally dividing the Oxfordian limestones into two parts in the NE zone of the study area. In the lower Oxfordian, water inflows come mainly from the outcrop in the southeastern part of the study area. Three meteoric water inflows were identified in the upper Oxfordian in the study area: the first one covers the eastern and southeastern part of the area, the second one covers the diffuse fracturation zone (DFZ) south of the area, and the third one is located in the north eastern part + of the area. The two first inflows consist of fresh water, while the last one consists of Mg2+, SO2 4 and Na rich waters coming from the erosion of the Purbeckian lithological type facies. Fresh waters from the outcrops flow slowly towards the North West. They equilibrate with the limestone dolomite formations and are enriched by a Na+ and Cl diffusive flux coming from the Dogger through the Callovo-Oxfordian argillaceous rock. These waters mix with the water coming from the North East upper Oxfordian. The Dogger limestone is characterized by sodium chloride groundwaters with higher salinity values than the Oxfordian limestone. North–northwest flows in the Dogger limestone are slower than flows in the Oxfordian formation. In both formations, the DFZ must be considered to be an apart hydrological system. Ó 2011 Elsevier Ltd. All rights reserved.

1. Introduction Within its scientific program dedicated to studying the feasibility of a high level radioactive waste disposal in the CallovoOxfordian argillaceous rock formation (COx), Andra (French National Radioactive Waste Management Agency) has conducted an extensive characterization of the Oxfordian and Dogger limestone formations above and below the Callovo-Oxfordian formation. Forty-four wells, 400–2000 m in depth, were drilled over 15 years to study a 400 km2 sector around the Andra Meuse/Haute-Marne Underground Research Laboratory (URL) at Bure (France – see Fig. 1). This data acquisition has been conducted through several drilling surveys, each one with specifics objectives (Delay et al.,

⇑ Corresponding author. Fax: +33 3 29 75 53 89. E-mail address: [email protected] (Y. Linard). 1474-7065/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.pce.2011.07.012

2007). All of them have improved the geological, hydrological and geochemical knowledge of the Jurassic series in this area of the Paris Basin:  1994–1996, site investigation phase, seven boreholes (2 Kimmeridgian, 3 Oxfordian, 2 Dogger),  1999–2002, characterization of the URL site (excavation of the access shafts to the underground facilities and wells), six boreholes (2 Kimmeridgian, 2 Oxfordian, 2 Callovo-Oxfordian),  2003, FSP (Forages Scientifiques Profonds – Deep Scientific Drillings) survey, eight boreholes (5 Oxfordian, 3 Dogger),  2004, FRF survey (Forages de Reconnaissance de la Formation – Host Formation drillings), nine boreholes mainly within the URL perimeter (1 Oxfordian, 7 Callovo-Oxfordian, 1 Dogger),  2007–2008, FZT survey (Forages de la Zone de Transposition – Transposition Zone Drilling Survey), fourteen boreholes (5 Oxfordian, 3 Callovo-Oxfordian, 5 Dogger, 1 Triassic).

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

1451

Fig. 1. Location of the Meuse/Haute-Marne URL in the Paris Basin.

A unique set of 3D data was obtained through this multidisciplinary work. This paper first presents the geological setting and the original combination of hydrogeological measurements and water sampling methods used in the dedicated wells. A short description of the water analysis methods is also included. The hydraulic head and water geochemical data of the last survey (referred to as FZT) are then described. The previous surveys were presented in other papers (Delay, 2004; Distinguin et al., 2004; Andra, 2005; Vigneron et al., 2005; Delay et al., 2007; Cruchaudet et al., 2007; Buschaert et al., 2007). Finally, we propose an integrated geological, hydrogeological and geochemical interpretation of the Oxfordian and Dogger limestone water flows and solute transfers at the sector scale.

2. Geological setting 2.1. Location and structural setting The study area is located on the Jurassic outcrop wide strip of the Eastern part of the Paris Basin (Fig. 1), close to the first Lower Cretaceous outcrops appearing to the west. In this area of the basin, the general dip of the sedimentary series is about 1° to the west. The study area is structurally limited to the south by the Vittel fault an E–W Hercynian inherited structure limitating a thick Permian basin to the North. This structure was also active during

1452

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Fig. 2. Geological settings of the study area and borehole location.

the Triassic, at least in its upper part, when a salt basin developed to the North of the fault, and probably between the Lower and Middle Jurassic (Mid-Cimmerian Unconformity; Guillocheau et al., 2000). To the West, the study area is bounded by the Marne fault system (Fig. 2), another Hercynian inherited structure, but with a N–S direction, also limitating the Permian basin. The Poisson fault system, with a NW–SE direction, is the last structure to reach the crystalline basement in the study area (Fig. 2), but its relation with the other structures remains unclear. The Marne and Poisson fault systems define a zone commonly referred to as the ‘‘diffuse fracture zone’’ (DFZ). In the north of the study area, the only observed structure is the Savonnières syncline, a W–E weakly curved trough affecting all the series. Younger major structures are also present, such as the SW–NE Gondrecourt trough, the closest to the URL, and its parallel and contemporaneous Joinville trough (Fig. 2). These structures formed, and were active, during the Tertiary orogenesis (Pyrenean and Alpine, respectively Eocene and Miocene) and extensive phases (Oligocene; André, 2003) during which the Hercynian structures were active again. 2.2. Stratigraphy A well was bored near the URL (EST433 well) to reach the base of the Triassic in order to estimate the geothermal potential. This well allows illustrating the entire Mesozoic local succession (Fig. 3; Landrein et al., in preparation). Above the Vittel fault to the North and to the East of the Marne fault system, a Permian sedimentary succession, mainly composed of conglomerates, covers the crystalline basement. The Triassic lies directly on the basement to the South and East of the Vittel and Marne faults, respectively, and mostly corresponds to a 750 m thick succession of siliclastic fluvial, coastal (including sabkha) and shallow-marine deposits. A 200 m thick salt and evaporate pile of Keuper age is also recognized in the succession (Fig. 3). The Lias

corresponds to a 300 m thick succession dominated by silty claystone and marls with the exception of several thin limestone and sandstone levels (Fig. 3). The readers should refer to Landrein et al. (in preparation) for a detailed study of the Triassic and Liasic series. A more thorough description of the overlying Middle and Upper Jurassic sedimentary succession is proposed below since these limestone dominated deposits are the focus of this work. The Dogger corresponds to the development of carbonate platforms in the Paris Basin (Purser, 1975; Gaumet, 1997). A Bajocian platform, dominated by reefs and crinoids, developed first over the entire Paris Basin (Thiry-Bastien, 2002). After a clastic dominated interval (‘‘Marnes de Longwy’’; Fig. 3), a mainly oolithic Bathonian isolated platform extended from Burgundy in the SE to the Paris region in the NW (Purser, 1975; Gaumet, 1997). The study area is located on the North East margin of the latter platform. The Bathonian limestone formation corresponds to the immediate basement of the Callovo-Oxfordian clays, the URL target. It is the first aquifer encountered in the Jurassic succession and it is studied in this work. The 150 m thick Callovo-Oxfordian clays follow the disappearance of the Dogger platform. Above these clays, an Oxfordian platform developed with reefs and oobioclastic facies. The geometry and paleogeography of this platform is complex (Ferry et al., 2007; Carpentier et al., 2007). The Oxfordian limestone formation is the second Jurassic aquifer. The Kimmeridgian follows the disappearance of the Oxfordian platform and corresponds mainly to a 150 m thick interval of marls and argillaceous limestone. A third Jurassic carbonate platform developed during the Upper Kimmeridgian and the Tithonian. The facies are mainly finer than in the previous platforms, except an oolithic marker bed easily identifiable in the middle of the ‘‘Calcaires du Barrois’’ formation called ‘‘Oolithe de Bure’’. The uppermost Jurassic and the transition with the Cretaceous is complex and has to be detailed. In the southern part of the study area, the ‘‘Calcaires du Barrois’’ formation is affected by a paleokarst

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

1453

Fig. 3. EST433 geological log.

over which directly lie the Valanginian continental to coastal sand and marls In the northern part, in the axis of the Savonnières

syncline, a sedimentary sequence is recorded between the non-kartsified top of the ‘‘Calcaires du Barrois’’ formation and the

1454

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Valanginian clastics (Fig. 3); this sequence includes a 3–4 m thick oobioclastic limestone bed (‘‘Pierre de Savonnières’’; Fig. 3), and a plurimeter thick succession of layered green dolomite and vuggy limestone (Purbeckian facies; Fig. 3) with abundant evaporites molds. The locally disturbed bedding of the Purbeckian facies may indicate a dissolution of evaporite beds and/or lenses. This geographical partition of sediments in the Uppermost Jurassic is due to the early formation of the Savonnières syncline during a weak North–South tectonic compression (Late Cimmerian Unconformity; Guillocheau et al., 2000). Either the Purbeckian facies, indicating a brine shallow-marine depositional environment, were present everywhere and were eroded during the earliest Cretaceous tectonic movements, or they were initially deposited in an already existing syncline. The latter hypothesis, however, implies latest Tithonian movements. However, the solution of this problem is not within the scope of this work. 3. Material and methods 3.1. Hydrogeological characterization and water sampling From 1994 to 2008, 16 wells were drilled to study the Oxfordian formation and 11 to study the Dogger limestone formation (Fig. 2). In addition, the two access shafts to the URL gave the opportunity to sample water flowing out from individual producing zones in artesian conditions. Hydrogeological measurements and water sampling were performed in the 100–350 m long open section of each dedicated well with the aim to:  Characterize each water-producing zone (location, thickness, local transmissivity),  Measure the global transmissivity (for the total length of the well),  Measure the depth-averaged hydraulic head,  Identify the water chemical composition of each distinct waterproducing zone. The following techniques were used to reach these aims:  The wells dedicated to hydrogeological measurements and water sampling were air drilled using the reverse circulation technique. This drilling method limits the cake formation on the well walls and fluid injection in the rock. Consequently, it is the best available drilling technique for hydrogeological and geochemical characterization.  A series of geophysical logs were performed. For instance, Nuclear Magnetic Resonance gave a vertical quantification of total and free fluid porosities.  Short term global pumping tests and two to three different flow logging techniques were implemented to identify the water producing zones and to measure the global and individual transmissivities.  Long term/high volume pumping tests were performed to obtain a stationary composition of the well water column.  The pumped water was sampled at the surface at the end of the long term/high volume pumping test.  Deep water samples were taken with the DIAPO pump (Sornein et al., 1992) or by using a borehole water sampler. 3.2. Identification of individual inflow zones and transmissivity measurements Three flow logging methods were used to characterize individual inflow zones in Oxfordian and Dogger limestone in wells:

vertical flowmeter logging (spinner), fluid conductivity (or geochemical) logging and heat-pulse flow meter logging (Delay, 2010). The vertical flowmeter logging directly measured the flow rate through the section hole with a spinner. The measurable flow rate ranged from 5 mm s1 to 1 m s1. The lowest transmissivity measured with this tool in the Andra wells was 105 m2 s1. The fluid conductivity logging (Tsang et al., 1990) consisted in replacing the natural water filling the borehole with water with a contrasted electrical conductivity. The inflow of natural water in the well was monitored using repeated electrical conductivity logging. The electrical conductivity logging showed peaks at the water inflow points. These peaks increased and moved along the hole depending on the inflow rates. Furthermore, the hydraulic interpretation of the pumping tests, associated with the analysis of fluid electrical conductivity logging in the wells, made it possible to estimate the inflow rates and transmissivity for each main inflow zone (Löw et al., 1984). This method helped to locate the main inflow zones and was ideal for detecting low inflow rates which could not be detected with vertical flowmeter logging (spinner). The range of measured transmissivities is between 1010 and 105 m2 s1. The heat pulse flow method was used to measure the flow rate of incoming/outcoming water in the defined well section (Paillet et al., 1996; Ohberg and Rouhiainen, 2000). This tool and method were developed by Posiva and PRG-Tec. The section isolates the flow of water in the test section from the flow in the rest of the well by means of rubber sealing disks (15 cm of diameter). The flow inside the test section is directed through the flow sensor. The flow along the well is directed around the test section by means of a bypass pipe and is discharged at either the upper or lower end of the probe. The flow rates of incoming/outcoming water in the test section are monitored using thermistors which track both the dilution of a thermal pulse and the thermal transfer by advection. The flows are measured when the probe is at rest. After measurement, the probe is moved step by step in a new position in the hole. Two logs are run, the first one without pumping and the second one with pumping (stabilization of the drawdown is required before logging). The two results obtained are compared to discriminate the inflow zones. This method can help discriminate detailed heterogeneities over a wide range of flow rates from 8.3  109 m3 s1 to 8.3  105 m3 s1. The process is entirely automated and can log a hole at 0.004 m s1 in 0.1 m increments. In the Andra wells, 1 or 5 m test section lengths and 0.5 m increment were used, except for one run into the EST421 borehole (12 m of test section length). The range of transmissivities varies between 3  1010 and 5  105 m2 s1. The quality of the measurements depends on the borehole wall, i.e. on the diameter. If the diameter of the borehole is larger than the rubber disks, the test section is not isolated from the rest of the borehole. The diameters of wells EST431, EST451 and EST461 were larger than 0.15 m, therefore heat pulse flow logging was not used in these wells. Hydro-geological operations performed in the wells dedicated to the study of the Oxfordian formation between September 2007 and November 2008 consisted of eight global pumping tests with 20 geochemical logs and 10 long term pumping tests (with 38 geochemical logs). For wells dedicated to the study of the Dogger formation, 11 global pumping tests, with 32 corresponding geochemical logs and 10 long term pumping tests associated with 15 geochemical logs, were performed. For each well, the global transmissivity was determined through the interpretation of flow/piezometric level data. The single transmissivity of each water productive level was estimated from analytical calculations based on the Cooper–Jacob method (Fluid Logging) or from the analysis of the flow differences (Thermal Flow Logging).

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

3.3. Hydraulic head measurements Gauges were installed in the wells to monitor the water levels over a period of several months. A remote data acquisition system was used to store the data in a central data bank. The hydraulic head was then deduced from a measurement analysis [Tabani et al., 2010]. The same strategy was used throughout the scientific investigations which began in 1994 (Delay et al., 2007). For the five wells drilled in the Oxfordian limestone formation, multipacker completions (five intervals) were used to monitor individual hydraulic heads. Three of these wells are located on the URL site and the two others in a fractured zone. Hydraulic heads measured in the wells dedicated to the study of the Oxfordian formation can be directly considered as fresh water equivalent heads because the density effects in Oxfordian groundwaters are negligible (Total Dissolved Solid – TDS – values range between 0.46 and 1.46 g/L). On the contrary, in wells dedicated to the study of the Dogger formation, differences in solute concentration vary more strongly (TDS values range between 1.68 and 7.77 g/L) and the densities of the water column of each well cannot be assumed to be invariant. In order to compare the hydraulic heads with each other, measured heads have been normalized with respect to a reference density: the fresh water density (qfw  1000 kg m3). The density of the column of water is calculated with the international equation of sea water IES80 (Unesco, 1981). This equation allows calculating the water density as a function of the salinity, the temperature and the in situ pressure (atmospheric pressure subtracted to the measured pressure):

qðS; T; PÞ ¼ qðS; T; 0Þ=½1  P=KðS; T; PÞ

ðIÞ

where S is the salinity expressed in g L1, T is the temperature, P is the in situ pressure and K(S, T, P) is the bulk modulus. In the case of a well, the column of water is in equilibrium with the atmospheric pressure, consequently, the in situ pressure is null and the temperature measured online on the water extracting line during the long term pumping can be used. In practice, the salinity is first calculated from the electrical conductivity directly measured on the water extracting line at the end of the long term pumping but later, TDS values are used when available. The equation giving the hydraulic head normalized with respect to fresh water is:

Hfw ¼ ½ðqmeas  hm Þ  ðqmeas  qfw Þ  Z f =qfw

ðIIÞ

where Hfw is the equivalent fresh water head expressed in meter above mean sea level (AMSL), hm is the measured head expressed in meter AMSL, Zf is the elevation of the well in meter AMSL and qmeas corresponds to the density of the water (considered as homogeneous). 3.4. Water sampling methods and field parameter measurements The hydrological tests (operations) gave the opportunity to sample waters after contaminating water (from drilling, openborehole flow, etc.) had been removed by pumping. Since 5 up to 50 casing volumes had been purged out by pumping in each well, and since the pH and electric conductivity had become stable at the end of the pumping, the geochemical data presented in this article are considered representative of the Oxfordian and Dogger formations. In the case of surface sampling, the sampling was performed after several weeks of pumping (at the end of a long term pumping). When several water productive levels were located in a borehole, surface samples were integrated groundwater samples of all the producing levels crosscut by the borehole. That is to say, they

1455

represented a mixture of all discrete levels (the contribution of each level was assumed to be proportional to the flow rate). In the case of deep sampling, samples taken with the DIAPO cabin (equipped with a submerged pump), or by using a borehole water sampler, allowed to distinguish different discrete levels: these techniques allow to sample a mixture of all water inflow zones located below the pump or the sampler. In general, the position of the pump is chosen after analyzing the logs so that the water taken is representative of the main water inflow zones. Deep sampling locations were chosen according to the electric conductivity contrasts measured during logging: water inflows with maximal electric conductivity were first sampled; wherever possible, sufficiently distinct intermediate saline water inflows were also sampled. The term ‘‘solution’’ is used in the rest of the document to describe each water family with a distinct electric conductivity range (difference less than 50 lS/cm). Each sample obtained with a pump had a total volume of about 40 L and was conditioned in about 30 different containers. For each sampling method, several water samples were conditioned in stainless steel or copper cylinders directly connected to the water extracting line in order to protect these water samples from any contact with the ambient air. pH and Eh were measured online on the water extracting line. Alkalinity was measured by titration (Gran’s method) on the field within 24 h. The other water samples were conditioned following procedures depending on the type of analysis: each procedure defined the container material, the volume and treatment, the way the container had to be filled, the water filtration if any and the chemical treatment if any. 3.5. Water analyses The water samples dedicated to total inorganic carbon were collected in stainless steel 40 mL-volume cylinders without contact with the ambient air. In the laboratory, the cylinders were connected to a special cell to measure the pH without contact with the ambient air. A few mL of water were immediately used for alkalinity measurement by titration. This measurement completed the one performed on site. Another 2 mL were immediately transferred to a special glass vessel including carbonate fixation over sodium hydroxide and acid. This sample part was used for the Gas Chromatography measurement of the total inorganic carbon (TIC) content according to the released CO2. The Na, K, Mg and Ca cations were analyzed with a Dionex ion chromatograph using an IonPac CG 12 A, 4  50 mm guard column and a CS 12 A, 4  250 mm analytical column. The Cl and SO2 4 anions were analyzed with a Dionex ion chromatograph using an IonPac AG 14, 4  50 mm guard column and a AS 14, 4  250 mm analytical column. Trace elements were determined through inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) using standard methods (DIN EN ISO 11885 and DIN EN ISO 17294-2). All isotopic analyses were performed by implementing standard methods using isotope ratio mass spectrometry (IRMS). All water analyses were individually recalculated with the PHREEQC code (Parkhurst and Appelo, 1999) and the thermochemical database THERMOCHIMIE (developed in collaboration with Andra, BRGM, CNRS and Enviros) to determine the molal concentrations of the various aqueous species present in each sample. In most water samples, the total cation charge (TZ+ in meq/L) balances that of the total anions (TZ in meq/L). Regression analyses of TZ+ and TZ yield a line with R2 = 0.99. The normalized inorganic charge balance (NICB = (TZ+  TZ)/(TZ+ + TZ)) is used to estimate overall analytical uncertainty and ideally it should be close to zero. NICB is within ±4% for most of the samples, showing the quality of analysis.

1456

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

4. Results 4.1. Hydrological survey The hydraulic heads and global transmissivities measured in each well are given in Table 1. Global transmissivities determined from all the wells dedicated to the study of Oxfordian limestone range from 1.3  107 to 2  103 m2 s1. Spatially, the transmissivity varies rapidly over short distances and the differences can be up to three orders of magnitude for wells five kilometers apart. Geographically, high transmissivity wells are restricted to the DFZ (3  105 to 1.3  102 m2 s1), whereas the wells with low to intermediate transmissivity are widespread in the rest of the study area (109 to 2  105 m2 s1). To understand this distribution, the relative contribution of each inflow point to the total transmissivity was determined. Fig. 4 shows the values of transmissivity in each lithologic unit and each well. In wells EST321, EST451 and EST461, single inflow points showing moderate to high hydraulic transmissivities ranging from 2.0  105 m2 s1 to less than 1  102 m2 s1 are located in the L1a, L1b and L2c units, respectively. These inflow points producing the largest contribution to the water flow are located along single open fractures and joints, while deeper lithological units (C3a and C3b), more shaly, do not represent a large contribution to the global transmissivity. As evidence of the role of fractures, seasonal fluctuations of the hydraulic head have been monitored in EST461 by using a multi-packer completion. Outside the DFZ area, dominant productive layers were identified in the L2c unit for EST311 (90% of total production), in the L2a unit for EST421 (68% total production), in the L2c unit for MSE101 (64% of total production) and in the C3b unit for EST431 (51% of total production). The L1a unit is productive in all wells of the study area. In wells of the URL site, in EST331 and in EST411, the L1a unit shows transmissivities overall higher than other lithological units. In this unit, several inflow points were identified. This unit is also productive in the EST311 and EST421 wells, but its contribution to the global production is less significant because it is masked by large inflows identified in other lithological units. Table 1 Global transmissivities and hydraulic heads measured in wells. Well

Global transmissivity (m2/s) Value

Hydraulic head (mAMSL)

Confidence interval

Oxfordian limestone EST311 1.6  105 EST321 3.0  103 EST351 5.0  106 EST411 1.4  106 EST421 2.1  105 EST431 7.2  106 EST451 1.4  102 EST461 8.3  103 MSE101 7.3  107 HTM102 6.5  107

5.0  106–2.0  105 2.0  103–4.0  103 3.0  106–7.0  106 6.0  107–3.0  106 1.0  105–3.0  105 5.0  106–1.0  105 6.0  103–1.6  102 4.1  103–1.7  102 5.1  107–1.0  106 1.3  107–3.2  106

264.00 ± 0.10 268.00 ± 0.50 273.00 ± 1.00 270.35 ± 0.10 253.40 ± 0.10 265.77 ± 0.10 210.50 ± 0.50 305.50 ± 0.50 256.00 ± 1.00

Dogger limestone EST312 2.0  107 EST322 4.0  106 EST342 1.0  107 EST412 6.5  108 EST422 2.9  106 EST432 6.8  105 EST452 8.0  106 EST462 3.1  105 MSE101 6.5  107 HTM102 2.1  108 EST210 7.3  107

7.0  108–3.0  107 3.0  106–8.0  106 1.0  107–2.0  107 4.0  108–9.0  108 1.0  106–9.0  106 4.0  105–1.0  104 4.0  106–2.0  105 2.0  105–5.0  105 2.1  107–2.1  106 4.1  109–1.1  107 3.0  107–1.0  106

292.00 ± 1.00 272.30 ± 0.20 251.00 ± 1.00 295.10 ± 2.60 283.90 ± 0.20 284.40 ± 0.20 266.00 ± 0.20 275.05 ± 0.20 286.00 ± 1.00 289.00 ± 1.00 286.00 ± 6.00

Some inflow points were identified in the L2c unit in all wells except wells EST351 and EST321. The production of this layer is particularly important in wells EST311 and MSE101. The L2b unit appears to be only productive in the URL wells and in EST431. The production of this layer ranges between 3% and 18% of the total production of these wells. The L2a unit is, in turn, productive in the URL wells and in EST421, EST411, EST311 and MSE101. The production of this layer is dominant for EST421 and ranges between 1% and 18% of the total production in the other wells. Some inflow points, with a minor contribution to the water flow, were also identified in unit C3b in wells EST351 and EST431. In the case of the Dogger limestone formation, transmissivities are generally lower than those measured in the Oxfordian limestone. The DFZ is again characterized by the highest values (3.1  105–8.0  106 m2 s1) but the global transmissivity measured in the EST432 well is also in this range. All other wells have a global transmissivity ranging from 2.9  106 to 6.5  108 m2 s1. The highest transmissivity values obtained in the DFZ are likely due to the occurrence of joints and open fractures. These fractures were observed during a video logging in the EST462 well. The major water inflows occur in the Bathonian, not in the Callovian. These inflows are mainly located in the Middle to Upper Bathonian, in granular limestone. Some low water inflows are still observed in the Callovian in EST342, EST412, EST432 and EST462. The most transmissive water inflows occur in the D4 unit (Fig. 5). These inflow points are associated with two porous layers located at the top of unit D4 and at the base of this unit (and/or at the top of the D3 unit). The layer identified at the base of D4 is observed in wells MSE101, EST432, EST422, EST412 and EST312. It is also visible in the EST462 well at the top of the D3 unit. This layer shows a facies similar to the chalky lagoonal limestone facies of the Oxfordian porous horizons. The facies is described as wackestone packstone, that is to say, as a calm deposit environment facies. The NMR porosity logs (Fig. 6) show a micro- to meso-porosity developed with modes between 100 and 200 ms, typical of an altered chalky micrite (Fleury et al., 2007). The second layer, located at the top the D4 unit, just below the boundary with the C1 unit, is well represented in the EST432 well where it corresponds to a package of oobioclastic limestone with a connected macroporosity, as illustrated by the T2 distribution profiles of the NMR tool (see Fig. 6). This layer also appears in wells MSE101, EST322, EST312 and EST210. It can be considered as a continuous horizon containing sub-kilometer size sections whose characteristics are very local (high transmissivity). In most boreholes located in the North East of the study area (and EST422 EST312), the inflow zones were identified only in the lower to middle Bathonian. 4.2. Water sample description Oxfordian groundwaters were obtained (see Table 2) from various locations at the Andra Underground Research Laboratory (URL): in the EST201 and EST203 boreholes and during the excavation of the main (boreholes PPA0012 to PPA0022) and secondary (borehole PAX0001) shafts. The most representative samplings were obtained during the excavation of the main shaft in artesian conditions (Antea, 2004). At the sector scale, Oxfordian groundwaters were characterized:  During the FSP survey (2003) in five wells: EST311, EST321, EST331, EST342 and EST351,  During the FSP survey in the MSE101 borehole,

225

S1

161

K2a

191

310

S1

S1

S2

L2b

295

L2c

S3

271 L1b

390

L2b

301

430

420

S3

S3

L1b

0.01

0.001

0.0001

1E-005

1E-006

L1b

300

490

320

510

S4 460

480

395

Minor inflows

530

340

550

360

L1a

S3 500

570

L1a

C3b

380

361 405

C3b

C3b

371 C3b

590

520

400

415 610

391

1E-007

280

470

385

381

260

440

375

351 L1a

1E-008 L2a

S2

321

341

0.01

240

L1b

450

L1b

S2 L2b

S2

L2a

400

365

331

0.001

410

380

325

355

0.0001

220 360

345

311

L2c

L2b

L1a

291

1E-005

180

S2 L2b

335

281

401

1E-006

1E-007

L2c

315

261

S1

160

200 340

L2a

251

140

370

305

241

K2a

K1

L2a

L2a

S1

K1

330 350

320

L2c

285

221

120

300

275

201

100

290

280

235

265

Depth (mBGL)

K2a

255 L2c

Transmissivity (m2/s)

K1

245

171

Depth (mBGL)

270

K1

151

Transmissivity (m2/s) 1E-008

1E-005

1E-006

1E-007

0.0001

1E-005

240

260

141 K1

231

Depth (mBGL)

215

131

211

1E-006

Depth (mBGL)

205

121 K2a

181

1E-007

1E-006

1E-007

1E-008

1E-009

111

Transmissivity (m2/s)

Transmissivity (m2/s)

EST461

EST451

425

L1a

435

C3b

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Fig. 4. Local porosity and transmissivity of boreholes EST411, EST421/422, EST431, EST451 and EST461 in the Oxfordian limestone formation.

2 /s) Transmissivity (m

Depth (mBGL)

EST431

EST421/EST422 (Oxfordian)

EST411

540 C3a

C3a

C3a

420

C3a C2d

560

411 0

0.2 0.4

NMR porosity (%)

0

0.2 0.4

NMR porosity (%)

630

C2d

C2d

C2d

0

0.2 0.4

NMR porosity (%)

440 0

0.2 0.4

NMR porosity (%)

0

0.2 0.4

NMR porosity (%)

Total Porosity (TNMR) Free Fluid Porosity (FFNMR) Porous horizons (Estimated porosity > 18% by "quick look" interpretation of gamma ray / sonic logs (Diastrata, 2008)

1457

 In the FZT survey (2007–2008) wells: EST411, EST421 et EST422, EST431, EST451 and EST461.

670

660

650

640

630

620

610

600

590

580

570

560

0

0.1 0.2

1E-010

1E-007

1E-008

1E-009

746

736

726

716

706

696

686

676

666

656

646

Free fluid porosity (FFNMR)

Total porosity (TNMR)

Porosity (%)

D3

D4

C1

C2a

Depth (mBGL)

0

0.1 0.2

1E-010

Porosity (%)

D3

D4

C1

C2a

Depth (mBGL)

1E-007

S1

1E-005

S2

790

780

770

760

750

740

730

720

710

700

690

680

0

0.1 0.2

1E-009

Porosity (%)

D4

C1

C2a

Depth (mBGL)

1E-007

0.0001

1E-006

Minor #1

1E-005

Minor #2

S1

C1

C2a

860

850

840

0

0.1 0.2

1E-010

Porosity (%)

D3

830 D4

820

810

800

790

780

770

760

750

Depth (mBGL)

1E-008

S1

1E-007

1E-009

1E-008

1E-006

1E-008

1E-009

Transmissivity (m2/s) 1E-006

Transmissivity (m2/s) 0.0001

Transmissivity (m2/s)

640

630

620

610

600

590

580

570

560

550

540

530

D3

D4

C1

C2a

Porosity (%)

0 0.2 0.4 0.6

Depth (mBGL)

Transmissivity (m2/s) 1E-008

Transmissivity (m2/s) 1E-005

EST462

1E-007

EST452

1E-006

EST432

0.0001

EST422

1E-005

EST412

1458 Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Fig. 5. Local porosity and transmissivity of boreholes EST412, EST422, EST432, EST452, and EST462 in the Dogger limestone formation.

The different water productive levels were located in porous horizons. It is possible to identify these horizons by assigning them

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

1459

Except in the fractured boreholes of the DFZ, the sampling of individual inflows was possible due to the overall weak transmissivities and the globally low amount of water produced by the wells. Thus, the strategy consisted in evaluating on field the best timing for sampling, which is most often the beginning of the stabilization of the electric conductivity values. Dogger groundwaters have been sampled (see Table 3):  In boreholes, MSE101 and HTM102, drilled during the preliminary site investigation phase (between 1994 and 1996), and after return to production in 2004 (during the FSP drilling survey),  In boreholes EST312, EST322 and EST342 drilled during the FSP drilling survey,  In the EST210 borehole drilled in the URL site area during the FRF drilling survey,  In boreholes EST412, EST422, EST432, EST452 and EST462 drilled during the FZT drilling survey (2007–2008). The main water inflows in the Dogger formation were found in the upper Bathonian levels in granular limestone (oolithic and bioclastic grainstones). A few water inflows were also found in the lower Bathonian and in the lower Callovian in EST412, EST432 and EST462. In addition to this set of data, surface waters were characterized in different studies: (i) drilling of water supply wells located near outcrop areas; (ii) springs with regard to the discharges. The surface points near recharge areas were used as a reference for the study of deeper waters of the Oxfordian and Dogger formations. 4.3. Groundwater geochemistry The analytical data on major ions contents, silica, Total Dissolved Solids and isotopic compositions of Oxfordian and Dogger groundwaters are reported in Tables 4 and 5.

Fig. 6. Relaxation time (T2) distribution in the Dogger formation (EST432 well).

to the corresponding lithological unit. Four families of porous horizons were differentiated:  Porous horizons located in the L1a unit. In a few cases, these horizons expanded in the inferior part of the L1b unit,  Porous horizons located in the L2a unit,  Porous horizons located in the L2b unit,  Porous horizons located in the L2c unit. Lithologic log (Fig. 3) allows the association of porous horizons with depositional facies. The porous horizons of the lithological unit L1a (upper part) up to L2c correspond mainly to fine limestone facies of inner platform (lagoon). However, the porous horizons of L1a expand in deeper fine limestone facies filling depressions located between decimeter scale coral buildups. Owing to the production rate of each inflow zone, the quality of the collected samples may be affected by mixing from various horizons. For instance, if the major flow comes from the upper part of the limestone formation, the water can be collected directly at the outflow of the pumping device and it is not contaminated by the deeper inflows which nevertheless can develop broad peaks. Thus the deeper inflows can be collected by means of a wireline sampler or the DIAPO pumping device. When the main inflow zone is at the bottom of the tested interval, the fluid may entirely mask the upper inflows, sampling is therefore more difficult and can be affected by a strong mixing.

4.3.1. Salinity and groundwater mineralization Electrical conductivity values estimated for each sample from the conductivity log are reported in Fig. 7. Substantial variations developed throughout the study area. Electrical conductivities of the Oxfordian groundwaters range from 426 to 1944 lS/cm and exhibit a large heterogeneity. The lowest measured conductivities were found in the EST321 and EST461 wells. The highest conductivities were measured at the location of the deepest water inflows in the EST411 and EST422 wells (Oxfordian part). In the Dogger formation, the electrical conductivity range is wider than for the Oxfordian groundwaters with values varying from 2390 to 13,180 lS/cm. Waters from the EST322 and EST462 wells show the lowest conductivities, while waters from the EST312 and EST422 wells show the highest values. The electric conductivity of the Trias sample obtained in the EST433 well is given for comparison, it is 166,000 lS/cm. Fig. 8 shows the TDS (Total Dissolved Solid) values calculated from the chemical composition of surface samples. As expected, the distribution of the TDS values is similar to the distribution observed in Fig. 7 showing electrical conductivities. The Trias and each encasing formation have their own salinity: in Oxfordian groundwaters, TDS values range from 130 to 1500 mg L1, in Dogger groundwaters values range from 1300 to 7600 mg L1 and in the Trias sample the salinity is equal to 179,000 mg L1. By comparison, groundwaters in the outcrop area show a low salinity (TDS: 80–200 mg L1). The lowest salinity values are those measured on samples from the EST321 and EST461 wells for the Oxfordian formation and the EST322 and EST462 wells for the Dogger formation. The highest values are associated with EST311 and EST421 for Oxfordian groundwaters and EST312 and EST422 for Dogger groundwaters.

1460

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Table 2 Oxfordian water sampling carried out in the Andra wells and boreholes. Location

URL

Well/borehole

Cirfontaines-en-Ornois Demange-aux-Eaux

PAX0001 PPA0012 PPA0013 PPA0015 PPA0016 PPA0017–18 PPA0019 PPA0020–21 PPA0022 EST331 EST311

Montreuil-sur-Thonnance Effincourt Nomécourt Morley

EST321 EST351 EST342a MSE101

Houdelaincourt

EST411

Tréveray

EST421

165 to 170 163 to 168 178 to 182 223 to 235 257 to 278 280 to 305 306 to 316 322 to 338 340 to 358 60 to 280 110 to 112 230 to 290 390 to 410 398 to 438 147 to 590 248 to 254 316 to 328 430 to 442 159 to 339 270 to 339 247 to 304 300 247 to 362 297 to 362 360 297 to 507 412 to 507 506 316 to 534 452 to 534 525 to 534 165 to 341 214 to 341 214 to 341

EST422a

Montiers-sur-Saulx

EST431

Narcy

EST451

Thonnance-les-Moulins

EST461

Depth (mBGL)

Sampled level Elevation (mAMSL)

Sampling method

201 to 196 203 to 198 188 to 184 143 to 131 109 to 88 86 to 61 60 to 50 44 to 28 26 to 8 319 to 99 167 to 165 47 to 13 25 to 45 38 to 78 146 to 297 12 to 6 56 to 68 162 to 170 189 to 9 78 to 9 61 to 4 8 61 to 54 11 to 54 52 61 to 149 54 to 149 148 83 to 301 219 to 301 292 to 301 201 to 25 152 to 25 152 to 25

Surface Surface Surface Surface Surface Surface Surface Surface Surface Surface Surface DIAPO Surface DIAPO Surface DIAPO DIAPO DIAPO Surface DIAPO Surface Sampler Surface Sampler Sampler Surface DIAPO Sampler Surface Sampler DIAPO Surface Sampler DIAPO

Solutions

Corresponding lithologic level and comments

S1 S1 S1 + S2 S3 S4 S4 + S5 S5 S6 S7 All S1 S2 S1 All All S1 S2 S3 S1 + S2 + S3 S3 S1 + S2 S2 S1 + S2 + S3 S2 + S3 S3 S1 + S2 + S3 S2 + S3 S3 S1 to S4 S3 + S4 S4 S1 + S2 + minor S S2 + minor S

L2c L2c L2c and L2b L2a L1a L1a L1a L1a L1a L2c to L1a L2c – Major inflow L1a L1a (Major inflow, joint) L1a and C3b L2c to C2d blowing L2c L2a C3b L2c–L1a L1b and L1a L2c–L2a L2a L2c–L1a L2a–L1a L1a L2c–C3b L1b–C3b C3b L2c–C3b L1a (major inflow/fracture) and C3b C3b (minor inflows) L2c–L1a L2b–L1a L2b–L1a

a The EST342 and EST422 boreholes (planned to the Dogger investigation) were stopped, in a first step, during the drilling of the Oxfordian formation because the occurrence of a strong water productive level. On this occasion, they were the object of tests for hydrological characterization and sampling. The Dogger investigation has been conducted after a second drilling step.

Table 3 Dogger water sampling realized in the Andra wells and boreholes. Location

Well

Depth (mBGL)

Sampled level Elevation (mAMSL)

Sampling method Surface DIAPO DIAPO Surface DIAPO Sampler Sampler DIAPO DIAPO DIAPO Surface Surface DIAPO Surface Surface Sampler Sampler Surface DIAPO Sampler Surface DIAPO Surface

Demange-aux-Eaux

EST312

562 to 597

282 to 320

Montreuil-sur-Thonnance

EST322

592 to 597 660 to 665

315 to 320 295 to 300

Nomécourt

EST342

648 to 662 708 to 710

355 to 369 415 to 417

Morley

MSE101

Cirfontaines-en-Ornois URL

HTM102 EST210

Houdelaincourt Tréveray

EST412 EST422

Montiers-sur-Saulx

EST432

Narcy

EST452

Thonnance-les-Moulins

EST462

665 725 479 560 560 567 698 725 710 693 720 765 775 789 544

405 465 127 192 192 219 390 417 402 335 362 407 542 556 178

to 617 to 700 to to to to to to to to to to

651 733 733 733 768 768 768 850 850 629

to 265 to 331 to to to to to to to to to to

303 425 425 425 410 410 410 617 617 263

Solutions

Comments

S1 + minors S S1 + minors S Minors S S1 + minors S S1 Minors S

Major inflow between 562 and 582 m BGL

S1 S2 All All S1 All inflows S1 + S2 S2 S1 + S2 S1 + minor inflows Minor inflow #1 Minor inflow #2 S1 + S2 S2 All inflows

Major inflow

Major inflow Major inflow

Major inflow between 698 and 703 mBGL

Artesian borehole Major inflow between 559 and 564 mBGL

Table 4 Major ions contents, trace elements content, silica, and isotopic compositions for Oxfordian groundwaters. EST411

Sample

EST03307F

EST03311F

EST02931F

EST421 and EST422 (Ox) EST02684F

EST02688F

EST02691F

EST431 EST03324F

EST03332F

EST03336F

EST451 EST03291F

EST02926F

EST03295F

EST461 EST03262F

EST03266F

Techniquea Solution T (°C) pH Alkalinity (mmole/L) Na (mmole/L) K (mmole/L) Ca (mmole/L) Mg (mmole/L) Cl (mmole/L) SO4 (mmole/L) NH4 (mmole/L) Br (mmole/L) F (mmole/L) I (mmole/L) Sr (mmole/L) Li (mmole/L) Si (mmole/L) TIC (mmole/L) NICB (%) TDS (g/L) d2H (H2O) – ‰VSMOW d18O (H2O) – ‰VSMOW d34S (SO4) – ‰CDT d18O (SO4) – ‰VSMOW

SP S1 + S2 + S3 15.7 7.5 5.51 3.783 0.228 1.014 2.618 1.411 2.073 0.083 0.00351 0.23704 0.00339 0.07424 0.00865 0.11402 6.39 0.95 0.79 60.2 8.94

Diapo S3 16.7 7.5 4.79 3.512 0.187 0.861 2.017 1.710 1.313 0.072 0.00338 0.26334 0.00237 0.05482 0.00865 0.12469 6.34 1.4 0.66 61.2 8.99

SP S1 + S2 17.4 7.4 6.86 6.315 0.397 1.736 4.283 1.759 4.722 0.128 0.00764 0.25296 – 0.10398 0.01587 0.13546 8.08 2.39 1.27 57.5 8.89

SP S1 + S2 + S3 17.9 7.4 7.56 6.533 0.384 1.594 4.003 1.983 4.169 0.128 0.00877 0.28458 0.00868 0.10512 0.01731 0.13190 7.86 0.88 1.24 53.3 8.03

DWS S2 17.5 7.4 7.27 6.837 0.379 1.526 4.114 2.180 4.378 0.122 0.00890 0.27404 0.00868 0.10284 0.01587 0.13190 7.31 1.02 1.28 – –

DWS S3 19.1 7.3 8.53 11.630 0.341 0.972 3.229 4.463 3.909 0.128 0.01379 0.31625 0.00947 0.07657 0.02020 0.13192 8.52 1.24 1.46 50.0 7.50

SP S1 + S2 + S3 20.1 7.4 5.39 3.051 0.251 1.014 2.762 0.793 2.094 0.089 0.00401 0.29497 0.00465 0.04226 0.01010 0.12827 6.16 1.84 0.75 59.2 8.84

Diapo S2 + S3 20.6 7.4 5.45 3.339 0.264 1.051 2.717 0.937 1.979 0.061 0.00301 0.26863 0.00536 0.04340 0.01010 0.13539 6.20 3.33 0.76 59.6 8.78

Diapo S3 20.9 7.4 5.34 3.600 0.253 1.061 2.577 1.042 2.219 0.083 0.00463 0.27918 0.00544 0.04112 0.01154 0.14252 6.21 0.00 0.79 59.9 8.80

SP S1 + S2 + S3 + S4 20.2 7.7 4.62 2.659 0.197 1.004 2.346 0.502 2.104 0.061 0.00250 0.23701 0.00434 0.04225 0.00865 0.13895 5.47 0.76 0.67 60.1 9.10

DWS S3 + S4 20.4 7.7 4.60 2.633 0.197 1.024 2.437 0.517 2.125 0.067 0.00263 0.22648 – – – 0.14251 5.38 1.22 0.67 59.8 9.12

Diapo S4 22.1 7.5 4.31 5.965 0.248 1.291 2.470 1.214 3.782 0.072 0.00551 0.21600 0.00868 0.05597 0.01731 0.14255 5.14 2.55 0.93 62.5 9.17

SP S1 + S2 14.8 7.3 5.11 0.587 0.087 1.710 1.230 0.508 0.307 – 0.00163 0.04002 – 0.01599 0.00245 0.11042 5.88 1.89 0.48 51.5 8.03

Diapo S2 15.1 7.4 5.20 0.418 0.072 1.448 1.481 0.248 0.282 – 0.00063 0.04107 – 0.01484 0.00159 0.13535 5.94 2.77 0.46 52.1 8.09

17.80 15.48

18.40 16.91

13.20 16.20

16.10 16.40

 –

15.90 14.50

22.3 15.58

22.2 16.89

23.2 15.60

17.8 15.72

– –

22.7 16.39

15.60 8.50

12.20 10.30

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

a

Well

SP: sampling at the end of a surface pumping; Diapo: sampling with the immerged pumping system, Diapo; DWS: sampling performed with a deep water sampler.

1461

1462

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Table 5 Major ions contents, trace elements content, silica, and isotopic compositions for Dogger groundwaters. Well

EST422

EST432

EST452

EST462

Sample

EST03050F

EST02838F

EST02805F

EST03320F

EST03328F

EST03299F

EST03303F

EST03286F

Techniquea Solution T (°C) pH Alkalinity (mmole/L) Na (mmole/L) K (mmole/L) Ca (mmole/L) Mg (mmole/L) Cl (mmole/L) SO4 (mmole/L) NH4 (mmole/L) Br (mmole/L) F (mmole/L) I(mmole/L) Sr(mmole/L) Li (mmole/L) Si (mmole/L) TIC (mmole/L) NICB (%) TDS (g/L) d2H (H2O) – ‰VSMOW d18O (H2O) – ‰VSMOW d34S (SO4) – ‰CDT d18O (SO4) – ‰VSMOW

SP All 25.5 7.1 4.31 86.271 0.772 4.622 8.406 89.169 9.747 0.396 0.22048 0.21197 0.02142 0.28726 0.10447 0.08603 4.78 4.36 6.84 38.5 6.31 27.2 16.1

SP S1 + S2 29.6 7.1 4.66 98.188 0.789 5.834 8.414 102.610 11.015 0.397 0.22448 0.23869 0.02422 0.40254 0.11037 0.15787 4.82 0.4 7.77 37.5 5.89 28 14.9

DWS S2 29.6 7.1 4.74 97.523 0.789 5.984 8.124 99.478 11.539 0.397 0.22446 0.24398 0.02382 0.33351 0.11182 0.19015 4.74 0.04 7.68 – – – –

SP S1 27.6 7.1 6.28 30.966 0.410 1.754 3.794 22.343 6.732 0.139 0.04266 0.26388 0.00948 0.13732 0.04335 0.12852 7.14 0.68 2.73 52.1 7.94 26.2 15.81

Diapo Minors S 27.6 7.1 6.25 33.764 0.436 2.049 3.915 25.148 7.099 0.206 0.05271 0.27978 0.00948 0.14880 0.04770 0.17140 7.32 0.86 2.94 52.7 8.03 26.9 17.08

SP S1 + S2 32.5 6.9 6.09 40.809 0.516 2.529 3.677 30.850 8.701 0.245 0.07911 0.24824 0.01186 0.12597 0.06073 0.20007 7.53 0.38 3.47 44.3 6.84 33.1 16.64

Diapo S2 32.7 6.9 6.08 39.585 0.503 2.479 3.718 29.292 8.920 0.239 0.07659 0.24822 0.01265 0.12596 0.06073 0.20363 7.45 0.52 3.41 46.3 7.17 33.8 15.99

SP All 23.3 7.5 6.33 19.780 0.305 0.795 1.796 11.301 3.493 0.117 0.02758 0.26888 – 0.11203 0.02743 0.18545 6.93 1.5 1.68 60.6 9.1 7.7 12.8

SP: sampling at the end of a surface pumping; Diapo: sampling with the immerged pumping system, Diapo; DWS: sampling performed with a deep water sampler.

μ

a

EST412

μ

Fig. 7. Electrical conductivity values estimated for each sample from the conductivity log (d Oxfordian, h Dogger, N Trias).

4.3.2. Major species The results of the chemical analyses of all the borehole waters, as well as those of surface waters, are plotted on a Piper diagram (Fig. 9). This diagram shows that surface waters at outcrops are similar for the Dogger and the Oxfordian with a high proportion of Ca2+ and HCO 3 , whereas there is a clear distinction between sodium chloride Dogger groundwaters, calcic-bicarbonate to sodium magnesium sulfate Oxfordian groundwaters and sodium chloride Trias groundwaters. In the cation (Ca/Mg/Na + K) triangle, Oxfordian groundwaters extend on a line toward the Na + K endmember. Exceptions to this trend are waters from the diffuse fracturation zone (EST461, EST321 and EST351) which are close to the outcrop waters. Dogger groundwaters, more alkaline, extend between the Oxfordian domain and the Na + K endmember. In the triangular diagram concerning anions (Fig. 9), Oxfordian groundwaters extend between the carbonate endmember and the sulfate endmember. Groundwaters of wells EST461, EST321

Fig. 8. TDS values calculated from the chemical composition of surface samples (d Oxfordian, h Dogger, N Trias).

and EST351 are less sulfated and closer to the outcrop waters. Other Oxfordian groundwaters form a set with two stretching axes: one toward the Cl endmember and the other toward the sulfate endmember. Dogger groundwaters define an alignment with an endmember corresponding to the Cl endmember. The Trias sample is also on this line. The principal component analysis (PCA) was used with the aim to establish associations between the physico-chemical variables of the waters and to note any correlation. For the Oxfordian samples, the results of the principal compo2+ nent analysis (PCA) concerned seven concentrations: HCO 3 , Ca , Mg2+, Na+, K+, Cl, SO2 coming from samples collected during 4 the FZT and FSP surveys, from the laboratory area and from outcrops. Three factorial components were selected which account for more than 97% of the variance in both analyses (Table 6). The first component (PC1) expresses 77% of the variance. It 2+ reveals strong associations between the ions SO2 and Na+. 4 , Mg This component may be related to the processes associated with the supply of ion-rich water. This contribution is very significant in the North-East of the study area (EST311, EST411 and EST421

1463

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468 Table 6 Principal component analysis (PCA) for Oxfordian Groundwaters. PC1

PC2

PC3

3.28 16.98 94.28

0.59 3.06 97.34

0.66 138 0.14 21.89 31.46 38.94

7.82 13.93 0.01 10.56 47.86 19.29

57.61 0.95 0.07 25.59 0.10 0.80

5.54

0.54

14.87

0.370 0.542 0.792 0.923 0.864 0.944

0.598 0.807 0.099 0.300 0.499 0.311

0.688 0.090 0.112 0.198 0.010 0.027

0.828

0.121

0.270

Factorial components table Value 14.94 Variance (%) 7730 % cumulive 77.30 Main axis table Ca2+ Cl K+ Mg2+ Na+ SO2 4 HCO 3 Multiple correlation table Ca2+ Cl K+ Mg2+ Na+ SO2 4 HCO 3

Fig. 9. Results of groundwater analyses plotted in a piper diagram.

wells) and becomes less significant in the central part of the study area. Finally, it seems to disappear in the south expansion of the DFZ (EST321 and EST461 wells). The second component (PC2) con 2+ sists mainly of variables such as Na+, SO2 4 , Cl and Mg . This factor allows differentiating waters from the EST311 well and those of the EST421 well. EST311 is mainly represented by the first component. The third component (PC3) shows a strong relationship between Ca2+, Mg2+ and HCO 3. The same method was implemented for the Dogger water analysis (Table 7). The first component (PC1) expresses 99% of the variance. It shows a strong relationship between Cl and Na+. The second component (PC2), which represents less than 1% of the  variance, consists of variables such as Na+, SO2 4 and HCO3 . 4.3.3. d2H and d18O water isotopes The plots of all analyzed groundwaters are either near or on the Global Meteoric Water Line (GMWL), thereby showing the meteoric origin of the Oxfordian and Dogger groundwaters. The difference between the plotted points compared to the GMWL could be explained by a local meteoric water line, a common fact in stable isotope geochemistry of meteoric waters. All of the studied Oxfordian groundwaters provide d18O and d2H values in a relatively restricted domain on the GMWL (Fig. 10), with d18O and d2H data ranging from 9.34‰ to 7.5‰ and from 64.2‰ to 50‰VSMOW, respectively. The more negative values correspond to groundwaters sampled in the EST321 well. The groundwaters which are less depleted in heavy isotopes are those sampled in the DFZ, in the EST461 well. The Dogger groundwaters spread out over a broad range of variations on the GMWL, with d18O and d2H ranging from 9.1‰ to 5.3‰ and from 60.6‰ to 33.6‰VSMOW, respectively. Particularly enriched values exist for waters from the EST312 and EST342 wells. However, for each borehole, the different water productive levels lead to similar d18O and d2H. Two wells, EST462 and EST322, produce groundwaters depleted in heavy isotopes, with a signature in the Oxfordian domain in the d18O versus d2H diagram (Fig. 11). 4.3.4. d34S and d18O sulfate isotopes Oxfordian groundwaters seem to stand out in two groups in the d34S versus d18O diagram of dissolved sulfates (Fig. 12). The first one

Table 7 Principal component analysis (PCA) for Dogger groundwaters. PC1

PC2

PC3

24.53 0.78 99.88

2.46 0.08 99.96

0.09 58.03 0.00 0.31 41.30 0.25

0.06 37.49 0.01 0.21 48.67 12.16

0.57 3.97 0.27 5.62 9.92 71.84

0.01

1.40

7.80

0.917 0.997 0.881 0.978 0.995 0.787

0.067 0.071 0.176 0.071 0.096 0.486

0.066 0.007 0.262 0.117 0.014 0.374

0.549

0.519

0.388

Factorial components table Value 3100.3 Variance (%) 99.10 % cumulive 99.10 Main axis table Ca2+ Cl K+ Mg2+ Na+ SO2 4 HCO 3 Multiple correlation table Ca2+ Cl K+ Mg2+ Na+ SO2 4 HCO 3

corresponds mainly to groundwaters from the EST461 and EST321 wells. This group is characterized by low values of d34S and d18O. The second group concerns all other samples. The d34S–d18O domain of this group varies from 13.2‰ to 23.2‰ CDT and 14.5‰ to 21.2‰VSMOW, respectively. The same separation is visible in the Dogger samples: EST462 and EST322 waters are apart from the other samples. 5. Discussion 5.1. Water origin The recharge zones of the Oxfordian aquifer are mainly located in the southern and eastern outcrops of the Oxfordian formation. The eastern Oxfordian outcrops are more shaly, and the recharge is therefore limited. Due to alteration by meteoric waters (crayification), the Oxfordian limestone formation shows higher permeabilities at outcrops than in the subsurface. Substantial formation of karst system. The

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

δ

1464

δ Fig. 12. d34S versus d18O diagram of dissolved sulfates in Oxfordian groundwaters.

formation of a substantial karst system occurred on the South-Eastern sector plateau. In depth, at a distance from the outcrops and outside fracture areas, the main groundwater flows are concentrated within the porous horizons. The vertical connection between each of these layers by microfracturing explains the single head measured in the Oxfordian formation in the study area. The waters sampled at outcrops have already been described in another paper (Matray et al., 2001; Buschaert et al., 2007), we will only sum up here the main features of these waters. The stable isotope content of these waters displays small variations (d2H between 44‰ and 51‰VSMOW and d18O between 6.9 and 7.9‰VSMOW (Figs. 10 and 11). The 14C activities of the dissolved inorganic and organic carbon are also consistent with a recent recharge of the shallow aquifer (Matray et al., 2001). Speciation calculations (Buschaert et al., 2007) indicate that this type of groundwater is in equilibrium with calcite and quartz, and under-saturated with respect to other carbonate and sulfate minerals. Partial pressures of CO2 are around 1.8  102 and 2.2  103 bar. According to their isotopic composition (Figs. 10 and 11), all groundwater samples from the Oxfordian and Dogger limestone formations have also a meteoric origin. Their dispersion on the GMWL could be mainly accounted for by the various temperature conditions during their infiltration in the porous layer. Water from EST461 has the same isotopic water signature than water coming from outcrops. Moreover, the salinity values of Oxfordian water obtained from wells located in the DFZ are higher but close to the shallow groundwater. In addition, isotopic signatures of dissolved sulfates measured in waters from EST321 and EST461 indicate a younger water contribution than other samples. Thus, these similarities and the high transmissivity values in the DFZ

are in agreement with a fast recharge from the outcrop area. Surface waters, vertically above the DFZ, could also act as a minor contribution to the recharge. Indeed, seasonal variations have been recorded in the EST451 well equipped with a multipacker completion. The Dogger waters collected in the DFZ (EST322 and EST462) have d18O and d2H values ranging in the same domain than those of the most Oxfordian groundwaters and the transmissivity is again high. The recharge of the Dogger aquifer is therefore also assumed to be fast. However, no seasonal variation in heads was recorded, which indicates an attenuation of the peculiar effect of the DFZ in depth. Moreover, the strong mineralization contrast between Oxfordian and Dogger waters, the piezometric characteristics and the chemical analysis performed on fluids clearly confirm the hydraulic independence of the Dogger limestone with respect to the Oxfordian limestone and the absence of local vertical recharge to the aquifer in this area.

δ

Fig. 10. d18O versus d2H diagram for Oxfordian groundwaters.

δ 18

2

Fig. 11. d O versus d H diagram for Dogger groundwaters.

5.2. Specificity of the upper Oxfordian North-East sector Groundwater sampled in the EST311 well at 110 m depth (L2c lithological unit) is characterized by high magnesium and sulfate contents, whereas underlying water productive levels have a strictly sodium chloride bicarbonate signature. This feature is also observed for the water inflow at 248 m in EST421, located a few kilometers to the west and, to a lesser extent, for the water inflow at 167 m in EST411 located a little further south. Fig. 13 shows a strong correlation between the Mg2+ contents and the SO2 4 contents of the Oxfordian waters. In Fig. 13, points corresponding to data from the shallowest samples produce a straight line between the low values associated to EST461 and the high values from the inflow at 110 m in EST311. This line suggests a mixing between two endmembers: a magnesium sulfate pole located North-East of the sector and a pole with low magnesium and sulfate contents located South of the DFZ. The origin of sulfates could be minerals such as celestite and barite which are occasionally found in the Oxfordian limestone. Celestite and barite, however, are poorly represented in the Oxfordian limestone which makes this hypothesis unconvincing. Gypsum or anhydrite could be other candidates for the origin of sulfates but groundwaters are sub-satured with respect to these minerals (saturation index with respect to gypsum are between 1.21 and 2.23 and those with respect to anhydrite vary between 1.45 and 2.5). However, waters are supersaturated with respect to dolomite (Saturation index with respect to dolomite are between 0.45 and 0.98), and dolomite and anhydrite are mainly associated in sedimentary and diagenetic processes through co-precipitation phenomena (e.g. Busenberg and Plummer, 1985). It is therefore likely that the

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

2+ Fig. 13. SO2 contents of Oxfordian groundwaters. 4 versus Mg

observed magnesium sulfate intake comes from interactions between water and sediment showing the association anhydrite/ dolomite. In addition to the high magnesium and sulfate content, the shallowest waters of the North-East sector coming through the L2c unit have a different Na+/Cl ratio than the underlying groundwaters. Fig. 14, where sodium contents are presented versus chloride contents, illustrates this point. In this figure, several trends can be inferred. The groundwater samples coming from the inflow points sampled during the excavation of the main shaft of the URL form a first linear trend. By taking into account the vertical location of the inflow points, this trend suggests that Na+ varies like Cl according to depth: the deepest water productive zone has the highest Cl and Na+ contents and the shallowest have the lowest chloride and sodium contents. The chloride content variations with respect to the depth in Dogger, Callovo-Oxfordian and Oxfordian formations have been illustrated by Vinsot (2010). As discussed by Vinsot (2010), these variations testify to an ascending vertical diffusive gradient in the three formations. Our data suggest that not only chloride but also sodium are vertically transported in the Oxfordian limestone according to a diffusive mode. The Na+/Cl correlation can be transposed to some other wells like EST431 and to deep inflow points (deeper than the L2a unit), EST421 (Fig. 14). This correlation is not valid for the shallowest water productive zones (inside the L2c unit) of the North-East sector: the water

Fig. 14. Na+ versus Cl in Oxfordian groundwaters.

1465

inflow at 248 m in the EST421 well is not lined up with water inflows at 300 m and 360 m. This productive zone at 248 m in EST421 and the samples of the inflow points at 110 m in EST311 and at 167 m in EST411 form a linear trend which could be considered as a mixing line. It is likely that the water chemistry of the shallowest inflows of wells EST421, EST311 and EST411 is affected by a sodium intake imposing variable sodium contents, depending on the distance from a sodium-rich area and also on the kinetic of the flow in the Upper Oxfordian. This sodium intake could mask the global Na+/Cl correlation observed in the other sectors. The geological investigations showed the occurrence of a brackish lagoon facies deposit including gray-greenish marly thinbedded dolomite with ghosts/molds of evaporitic minerals such as gypsum (CaSO4, 2(H2O)) and/or anhydrite(CaSO4). This is the Purbeckian facies deposit located above the ‘‘Pierre de Savonnières’’, lined up along the Savonnières syncline. To the East of the study area, the ‘‘Purbeckian’’ facies was extends beyond the Mauvages valley (Fig. 15A). In this sector, the lower Kimmeridgian and the upper Oxfordian outcrop. The surface waters, rich in magnesium and sulfate, were able to penetrate from this valley in the upper Oxfordian limestone. In the opposite, in the South direction (Fig. 15B), the ‘‘Purbeckian’’ facies is less extended and the Oxfordian limestone is always under cover (‘‘Calcaire du Barrois’’), thus the recharge waters from the south are not rich in sodium and sulfate. These high sodium and sulfate contents are only observed in water sampled from the L2c unit. This location could be explained by the occurrence of clay-rich layers in the L2b and L2a units which thicken towards the East of the study area, leading to the splitting of the Oxfordian aquifer into two aquifer layers: the first one in its upper part (including the L2c unit) and the second one in the lower part associated with the L1b and L1a units. 5.3. Water flow in the Oxfordian limestone formation At the study area scale, the Oxfordian limestone corresponds to the development of a single carbonate platform above the CallovianOxfordian. Directly above the laboratory, the interval between the Callovian-Oxfordian and Kimmeridgian marl is entirely limestone, except:  The lower part of the sequence (C3a/C3b unit) forming a transitional unit between the end of the Callovian-Oxfordian and Oxfordian limestones,  Two very thin marly layers (boundaries between L1b/L2a and L2a/L2b units). In the north-eastern sector, these layers thicken to form the ‘‘Série grise’’ of the Upper Oxfordian formation. To the west and southwest, towards the open ocean in the Oxfordian, marl and clayey limestone are dominant. Fig. 16a and b are piezometric maps which illustrate the groundwater flows in the Oxfordian aquifer. The piezometric surface for the Oxfordian aquifer follows the trend of the outcrop (Fig. 16) with a northerly hydraulic gradient. In the middle Oxfordian aquifer, a large ‘‘tongue’’ extends towards the north. This ‘‘tongue’’ represents a major flow zone within the aquifer. The flow zone is controlled by lithological and structural factors influencing both the movement and salinity of the groundwater. The dominant 2+ ions are HCO and Na+. 3 , Mg A limit is proposed to differentiate a North-East sector where upper and lower Oxfordian aquifers are distinct and where the thickness of the clay-rich layer in the L1b–L1a units is not sufficient to enable the efficient differentiation of both aquifers. This boundary is based on the geochemical data: the geochemical facies of waters of the upper productive zones in the EST311 and EST421 wells are well differentiated from others inflow points, whereas

1466

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Fig. 15. Global hydrogeological cross section showing the flowpaths from the outcrops and the origin of the different types of groundwaters.

the distinction is less significant in EST411. Therefore, this limit has been located between EST411 and the two other wells, EST311, EST421. It corresponds to a total thickness of the clay layer in the L2a and L2b units equal to 47 ± 1 m. Depending on the considered level, the main flow directions within the Oxfordian are actually slightly different: the main flow direction is south to north/northwest (Fig. 16a), whereas in the Upper Oxfordian and Kimmeridgian limestone, a component

oriented east–west appears toward the North-East sector (Fig. 16b). In the center of the study area, around the URL, there is only one aquifer, whose flows are controlled by a single charge field (Fig. 16a and b). In the more transmissive diffuse fracture zone (west of the study area), the role of the open fractures promotes a faster recharge than in the central part. This is also confirmed by isotopes of water and dissolved sulfates. The DFZ has to be considered as

Fig. 16. (a) Middle Oxfordian and (b) Upper Oxfordian.

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

1467

Fig. 17. Piezometric map of the Dogger limestone formations.

being apart from the continuous medium defined by the rest of the study area. Therefore, the isopiezometric lines have not been precisely defined for the DFZ in the piezometric maps.

5.4. Water flow in the Dogger limestone formation The piezometric map of the Dogger (Fig. 17) was built from a hydraulic head corrected by taking account of salinity, density, and the head measured at the outcrops. Outside the fracture zones, the low transmissivity of porous horizons and the probable lack of connectivity in the most transmissive zones are the cause of slow flows. The flow comes from outcrops located on the plateau areas, particularly in the South-eastern sector, where the Dogger limestone shows evidence of karstification. The main flow, north– northwest (Fig. 17), is partly constrained by the extension of the oolithic shoal/barrier facies belt, in which more porous and permeable layers could potentially develop. However, this flow area is probably also constrained by the incisions of the Meuse and Marne valleys. The inferred hydraulic gradient is about 0.1% in the main flow axis. Due to the low gradient and the low transmissivities of the Dogger limestone formation, the groundwaters are gradually enriched in Cl coming from the Triassic formations through an ascending flow (Buschaert et al., 2007). Therefore, the Cl concentration increases in this zone. In the DFZ, the electric conductivities are much lower, suggesting a relatively rapid ingress of fresh water. High transmissivities

measured in open fractures in the EST462 well suggest that this DFZ plays a major role in the flow paths. As well as the Oxfordian, the DFZ has to be considered as being apart from the continuous medium defined by the rest of the study area. Therefore, as for Oxfordian formation, the isopiezometric lines have not been consolidated for the DFZ in the piezometric maps.

6. Conclusion The data presented here represent a major compilation of field data and chemical analyses of the limestone formation encasing the host geological formation chosen for a French nuclear waste disposal. The data analysis herein suggests that present-day recharge to the Oxfordian and Dogger aquifer is mainly restricted to the southern outcrop area. The main flow is led by a northerly hydraulic gradient in both aquifers. Furthermore, hydrogeological results suggest that the DFZ could not be considered to be part of the continuous medium defined by the rest of the study area. Groundwater in the Oxfordian aquifer shows significant lateral and vertical variations which fall under two major different water types: HCO3–Mg–Na–Cl and HCO3–SO4–Mg–Na–Cl. The hydrochemical analysis of Oxfordian groundwaters suggests that the quality of water is mainly controlled by the hydraulic properties of the system, by an ascending diffusive transport of Na–Cl and by the presence of SO2 minerals in the Purbeckian deposit overlaying the 4 Oxfordian limestone. The geochemical specificities of the upper

1468

Y. Linard et al. / Physics and Chemistry of the Earth 36 (2011) 1450–1468

Oxfordian led us to consider a water flow from the North-East sector to the central area able to dilute the Mg–Na–SO4-rich water of the upper Oxfordian limestone . The chemistry of Dogger groundwaters was found to be very different from that of the Oxfordian groundwaters. The waters are characterized by a sodium chloride facies and the salinity and chloride contents can reach between one, and two orders of magnitude higher than Oxfordian groundwaters. These major differences are assumed to be due to the low gradient and the low transmissivities of the Dogger limestone formation which impose a long residence time. Acknowledgements The work described in this study was part of the HAVL project carried out and sponsored by Andra. The authors would like to thank their colleagues C. Aurière, L. Lefebvre, H. Rebours, C. Righini, P. Robin, P. Tabani, P. Landrein for their help. They would like to thank A. de Henning for reviwing the English version. They also wish to acknowledge the high quality of the technical work performed by IRH, Geoter, Soldata, Hydroinvest, AF Colenco, Gaudriot, Boniface-Foraco, APEC, Soleo and Antea. They also remember the late J.J. Blanc (Boniface). References Andra, 2005. Dossier 2005 Argile: Évaluation de la Faisabilité du Stockage Géologique en Formation Argileuse - Rapport de synthèse. Andra, France. Available from: . André, G., 2003. Caractérisation des déformations méso-cénozoïques et des circulations de fluides dans l’Est du Bassin de Paris. Ph. D. Thesis, Earth Sciences, University of Nancy I, Nancy, 311 p. Antea, 2004. Rapport de synthèse de l’Oxfordien. Lot 4, Puits d’accès et auxiliaire. Andra Report No. D.RP.0ANT.04.021. Buschaert, S., Giannesini, S., Lavastre, V., Benedetti, L., Gaucher, E., Lacroix, M., Lavielle, B., France-Lanord, C., Bourles, D., Lancelot, J., Benabderrahmane, H., Dewonck, S., Vinsot, A., 2007. The contribution of water geochemistry to the understanding of the regional hydrogeological system. Mém. Soc. Géol. France 178, 91–114. Busenberg, E., Plummer, L.N., 1985. Kinetics and thermodynamic factors controlling the distribution of SO4 and Na in cacites and aragonites. Geochim. Cosmochim. Acta 49, 713–725. Carpentier, C., Lathuilière, B., Ferry, S., Sausse, J., 2007. Sequence stratigraphy and tectonosedimentary history of the Upper Jurassic of the Eastern Paris Basin (Lower and Middle Oxfordian, Northeastern France). Sediment. Geol. 197, 235– 266. Cruchaudet, M., Delay, J., Distinguin, M., 2007. Hydrogeological characterisation of the Oxfordian limestone at the Bure URL. in Laurence Chéry and Ghislain de Marsily, October 2007, Aquifer Systems Management: Darcy’s Legacy in a world of Impending Water Shortage, Taylor & Francis ed. IAH Selected Paper 10, Chapter 25, pp. 333–347. Delay, J., 2004. Hydrogeological Investigation in Deep Wells at the Meuse/Haute Marne Underground Research Laboratory, Northeastern France. EurEnGeo 0407/05/2004 Liège, Engineering Geology for Infrastructure Planning in Europe, Springer LNES No°104, 219-225. Delay, J., 2010. Technologies and techniques for characterizing clay siteschapter 6. In: Ahn, J., Apted, M.J. (Eds.), Geological repositories for safe disposal of spent

nuclear fuels and radioactive materials: advanced technologies. Woodhead Publishing Limited, ISBN 1 84569 542 9. Delay, J., Rebours, H., Vinsot, A., Robin, P., 2007. Scientific investigation in deep wells at the Meuse/Haute-Marne underground research laboratory, northeastern France. Phys. Chem. Earth 32, 42–57. Distinguin, M., Vinsot, A., Delay, J., 2004. Hydrogeologic characterization of the Oxfordian limestone for development of an Underground research Laboratory in the eastern Paris basin, France P0231; EGU04-A-05429; HS23-ATU4P-0230, European Geosciences Union 1st General Assembly Nice, France, 25–30 April 2004. Ferry, S., Pellenard, P., Collin, P.-Y., Thierry, T., Marchand, D., Deconinc, J.-F., Robin, C., Carpentier, C., Durlet, C., Curial, A., 2007. Synthesis of recent stratigraphic data on bathonian to oxfordian deposits of the eastern Paris basin. Mémoires de la Société Géologique de France 178, 37–57. Fleury, M., Santerre, Y., Vincent, B., 2007. Carbonate rock typing from NMR relaxation measurements. In: Proceedings of SPWLA 48th Annual Meeting, Austin, Texas, June 3–6, 2007. Gaumet, F., 1997. Fondements géologiques pour la modélisation stratigraphique des systèmes carbonatés. Le Jurassique moyen de l’Angleterre à la Méditerranée. Thèse de 3ème cycle de l’Université Claude-Bernard-Lyon1, 245p. Guillocheau, F., Robin, C., Allemand, P., Bourquin, S., Brault, N., Dromart, G., Friendenberg, R., Garcia, J.P., Gaulier, J.M., Gaumet, F., Grodoy, B., Hanot, F., Lestrat, P., Mettraux, M., Naplas, T., Prijac, C., Rigollet, C., Serrano, O., Granjean, G., 2000. Meso-Cenozoic geodynamic evolution of the Paris Basin: 3D stratigraphic constraints. Geodynam. Acta 13, 189–246. Landrein, P., Vigneron, G., Delay, J., Lebon, P., Pagel, M., in prep. Evaluation des transferts et de la température dans un système sédimentaire multi-couches mésozoïque du bassin de Paris: les forages Andra de la plate-forme de Montiers-sur-Saulx. Löw, S., Kelley, V., Vomvoris, S., 1984. Hydraulic borehole characterisation through the application of moment methods to fluid conductivity logs. J. Appl. Geophys. 31, 117–131. Matray, J.M., Michelot, J.L., Vidart, B., 2001. Site EST: caractérisation chimique et isotopique de l’eau et carbone organique et inorganique dissous dans les eaux des formations carbonatées affleurantes encadrant la couches des argilites callovo-oxfordiennes. Andra report n°D.RP.0ANT.00.067. Ohberg, A., Rouhiainen, P., 2000. Posiva Groundwater Flow Measuring Techniques. Posiva Oy Report 2000-12, Olkiluoto, Finland. Paillet, F.L., Crowder, R.E., Hess, A.E., 1996. High-resolution flowmeter logging applications with the heat-pulse flowmeter. J. Environ. Eng. Geophys. 1, 1–11. Parkhurst, D.L., Appelo, C.A.J., 1999. User’s Guide to PHREEQC (vers.2) – a Computer Program for Speciation, Batch Reaction, One-dimensional Transport and Inverse Geochemical Calculations. USGS Water Resource Invest. Report 99/4259: 312p. Purser, B.H., 1975. Sédimentation et diagénèse précoce des séries carbonatées du Jurassique moyen de Bourgogne. Thèse d’Etat, Université Paris Sud, 384 p. Sornein, J.F., Chiappini, R., Delay, J., 1992. Diagraphie chimique des eaux par pompage, Brevet CEA 92 03381. Tabani, P., Hermand, G., Delay, J., Mangeot, A., 2010. Geoscientific Data Acquisition and management System (SAGD) of the Andra Meuse/Haute-Marne Research Center. In: Andra, (Ed.), Clays in Natural & Engineered Barriers for Radioactive Waste Confinement, 4th Intern. Meeting, Nantes, France, March 29–April 1st, 2010, Abstracts: 253–254. Thiry-Bastien, P., 2002. Stratigraphie séquentielle des calcaires bajociens de l’Est de la France (Jura-Bassin de Paris). Thèse de 3ème cycle, Université ClaudeBernard, Lyon 1. Tsang, C.F., Hufschmied, H., Hale, F.V., 1990. Determination of fracture inflow parameters with a borehole fluid conductivity logging method. Water Resour. Res. 26, 561–578. Vigneron, G., Delay, J., Distinguin, M., Lebon, P., Trouiller, A., 2005. Apport des investigations multi-échelles pour la construction d’un modèle conceptuel des plates-formes carbonatées de l’Oxfordien moyen et supérieur de l’est du bassin de Paris. Bull. Info. Géol. Bassin de Paris 42 (3), 30–35. Vinsot, A., 2010. Profils de concentration en chlorures dans les forages de la campagne FZT. Andra Report No. D.NT.ASTR.09.0041.