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Introduction Intraprocedural assessment of mitral regurgitation (MR) is a challenging issue during the MitraClip procedure, which might influence not only the position but also the number of MitraClips implanted. Though transesophageal echocardiography (TEE) is the predominant tool used during the MitraClip procedure, MR assessment might be facilitated by a multimodality approach including continuous and simultaneous determination of left atrial and left ventricular (LV) pressure. Methods 86 consecutive patients (76.5 ± 8 years) who qualified for the MitraClip procedure were included into the study. In all patients, the multimodal assessment of MR (TEE, LV angiogram, TEE bubble evaluation, left atrial (LA) pressure => MitraScore) was performed after introducing the MitraClip guide catheter. In the first 42 patients (group A, no CAP), left atrial (LA) pressure (peak pressure of V-wave) was determined only before and after MitraClip implantation, whereas, in the subsequent 44 patients (group B, with CAP), continuous left atrial pressure monitoring (CAP) was performed. Results Patients with CAP (group B) had similar total procedural durations and no increase in the complication rate. MitraScore decreased from 10.5 to 3.5 in group A compared to 10.7 to *2.8 in group B (*P = 0.021 vs. group B). Whether the significant improvement of intraprocedural MR in group B translated into superior MR reduction in the conscious patient, was analyzed by transthoracic echocardiography (TTE) in a blinded fashion. Again MR reduction was significantly greater (P = 0.03) in group B (MR grade 2.8 to 0.9) as compared to group A (MR grade 2.8 to 1.3) and 2D vena contracta decreased from 0.54 ± 0.15 cm to 0.17 ± 0.10 in group B compared to group A (0.56 ± 0.19 cm to *0.23 ± 0.12; *P = 0.01 vs. group B). Conclusions Multimodality assessment of intraprocedural MR supported by continuous left atrial pressure monitoring was associated with superior intraprocedural results translating into improved MR reduction also at the end of the hospital stay. © 2016 Wiley Periodicals, Inc.

This study focuses on the contrasted architectural elements of the two late Pleistocene alluvial fill sequences (T1 and T2 attributed to the Late Saalian and Weichselian) of the upstream Seine River alluvial plain, la Bassee, and constitutes the first estimation of the sediment volumes associated to these glacial cycles along this river. Estimations of the incised valley and valley fill spatial distribution are obtained by cokriging of data from 546 wells collected from the French national repository and a digital elevation model (DEM) of the present topography. The well stratigraphic attribution is given by the homogenised geomorphological map of la Bassee. We calculated the sediment volume of eroded material for the T1 sequence to be 1.70 109 m3 and of valley fill deposits to be 1.18 109 m3. This corresponds to a mean thickness of 6.1 m. By contrast, volumes of the T2 sequence are one-third smaller, 1.23 109 m3. The T2 mean thickness is very similar with 5.8 m. The alluvial plain is divided into four reaches representing a typical assemblage of the T1 and T2 incision style and valley fill deposits. Along the downstream reaches (1 - Montereau-Bazoches, 2 - Bazoches-Grisy), the T2 proportion per kilometer are close to the alluvial plain mean value (reach 1: 76%; reach 2: 69%, la Bassee: 71%), the T2 mean incised valley width corresponds to three quarters of the T1 (4 km). In the middle upstream reach (3 - Grisy-Courceroy), the T2 proportion is the largest (92%), the T2 mean incised valley width is the largest and comparable to the T1 (5.5 km). Along the upstream reach (4 - Courceroy-Romilly), the T2 proportion is the lowest (53%) and the T2 incised valley (2 km wide) is enclosed within the T1 incised valley (4 km wide). The rate of exported material, though, is the same for each sequence in any reach (31%). The spatial pattern of the T1-T2 deposits coincides largely with the presence of a knickpoint along the T2 paleothalweg (downstream part of reach 4, slope face 1.5‰), suggesting that the knickpoint had a large influence on the fluvial processes. The toe of the knickpoint (reaches 3 to 1, slope 0.24‰) was the site of the most efficient erosion of the T1 deposits. We propose that the change of slope favored diversion of the channel path. Upstream of the knickpoint face (upstream part of reach 4, thalweg slope 0.34‰), the incision processes were dominated by incision, avulsions or multithreading with limited lateral migration as indicated by the numerous T1 relicts preserved across valley. The sediment export corresponds to a mean incision rate of 40 m/Ma during the last 300 kyr; a fairly low value for the Paris basin, suggesting a low uplift area north of the Massif Central. Such contrast between the fluvial processes during the T1 and T2 sequences is most likely to be looked for in the climatic conditions that existed at the onset of the incision as no local controls for the knickpoint location could be identified such as active faults, substrate heterogeneity, or flow modifications. The lower sediment flux and the knickpoint associated to the T2 sequence suggest a transient river profile and valley incision at the end of the climatic transition associated to the Weichselian (T2).

A 75-year-old male presented to the emergency department at 2 a.m. with acute onset pulmonary oedema and evidence of cardiogenic shock (blood pressure 70/40 mmHg, tachycardia with a heart rate of 110/min). The initial oxygen saturation was 86 % with room air. The ECG showed ST-elevation in II, III, aVF and V5 ? V6 with corresponding ST-segment depression in V1–V4. A history of lung fibrosis and osteoporosis is reported, no cardiac comorbidity was known prior to admission. After haemodynamic stabilisation with inotropes, the patient was immediately transferred to the catheter lab with the working diagnosis of ST-segment elevation myocardial infarction (MI) and acute cardiogenic shock. An occlusion of the circumflex artery (RCX) causing lateral infarction was diagnosed (Fig. 1a). After recanalization and stenting a good reperfusion (TIMI III) was documented (Fig. 1b). During the procedure the patient remained in cardiogenic shock and required an intraaortic balloon counterpulsation system (IABP). Biochemistry from initial blood samples showed elevated creatine kinase (CK 2,577 U/l, CK-MB 429 U/l, Troponin-T 3.47 ng/ml), confirming the diagnosis of acute myocardial infarction. Furthermore blood samples showed an elevated creatinine and leucocyte count (creatinine 1.6 mg/dl, leucocytes 18 9 10 ll). After returning to the intensive care unit (ICU), an unstable haemodynamic situation remained with increasing inotrope requirement. Transthoracic echocardiography showed slightly reduced left ventricular (LV) function and a severe excentric mitral valve (MV) regurgitation. Partial rupture of the anterior papillary muscle, floating between left ventricle (LV) and left atrium (LA), was confirmed on transesophageal echocardiography (TEE) (Fig. 1c–f; Supplemental Video 1 and 2). Despite revascularisation and IABP support, the patient’s condition continued to progressively deteriorate. Therefore rescue cardiac surgery was considered, but the cardiac surgeon complained the patient to be at extremely high risk for emergency cardiac surgery. The heart team decided to use endovascular edge-to-edge valve repair as via MitraClip-implantation as bail-out procedure to eventually bridge the patient for later cardiac surgery. At 8:30 a.m. the patient was transferred to the catheter lab again, TEE-guided septal puncture and passage of the MitraClip-Device from the left atrium into the left ventricle was performed without difficulty (Fig. 2a). After a first unsuccessful attempt to simultaneously trap the ruptured papillary muscle and grab the posterior mitral leaflet, we inserted the MitraClip (open grippers, *140 ) slightly more medial in the A2/P2 segment. Now, we were able to push the ruptured papillary muscle back into the left ventricle by pushing with the posterior orientated cliparm against chordae connecting the posterior leaflet and the floating ruptured papillary muscle (Fig. 2b, step 1). When the posteriorly oriented cliparm was approximately 1 cm below the plane, a relatively strong movement towards Electronic supplementary material The online version of this article (doi:10.1007/s00392-014-0789-9) contains supplementary material, which is available to authorized users.

Fault systems can play a significant role regarding several risk issues related to CO2-injection-induced mechanical perturbations: fluid flow enhancement or compartmentalization within the reservoir, loss of integrity of the reservoir-caprock systems, potential triggering of seismicity and generation of new leakage pathways or permeability barriers. Several methods exist to model hydro-mechanical behaviour of fault zones. A first "conventional" approach aims at evaluating the fault response by directly post-processing the results of the large-scale coupled hydro-mechanical simulations. This consists of: estimating the changes of the effective stress field in the reservoir-caprock system during CO2 injection; computing changes of shear and normal stresses acting on the fault plane; comparing them to a fault reactivation criterion. However, this approach does not account for the effects of the presence of the fault on the stress and pressure field in the surrounding rock matrix. More sophisticated (and physically more realistic) modeling strategies have been proposed, which explicitly integrate the fault zone as a distinct element in the large-scale simulation, i.e. by representing it as a linear discontinuity with various hydraulic and mechanical properties. From a CO2 storage perspective, such a model still remains limited regarding two issues: 1. Faults are complex and heterogeneous geological systems, which do not correspond to discrete surfaces as already postulated by many authors. A fault zone is composed of an inner core made of fine material, often impermeable, and where slip is concentrated. It is surrounded by an outer damage zone that often acts as a hydraulic pathway, because of the presence of a fracture network, whose characteristics (fractures' orientation, connectivity, lengths, density, number of fractures' families, etc.) depend on the distance to the core; 2. Chemical interactions (dissolution and precipitation processes, chemically-induced weakening, etc.) between CO2-enriched brine and the minerals constituting the fault zone. can affect the mechanical and transport properties of the faulted/fractured system. In particular, chemo-mechanical processes can either stabilize the system if the compaction rate is increased or destabilize it if new micro-fractures are created. The FISIC project intends to overcome those limitations by accurately modelling the hydro-chemo-mechanical (HCM) complexity of a fault zone. The main goal is to provide appropriate theoretical and numerical models for accurate evaluation of fault stability in the context of CO2 geological storage, i.e. improving the stability analysis of a fault both undertaking pressure increase and alteration due to the presence of an acidic fluid. Four research questions are addressed and the progress regarding each of them is presented: 1. How to represent a fault zone in a tectonic setting, which has a priori been selected far from major potentially seismically-active faults, i.e. a moderate-to-low-deformed setting; 2. What are the fractures' organization within the damage zones of faults, i.e. their spatial distribution? 3. What are the dominant chemo-mechanical processes resulting from aqueous CO2 in fractured/faulted systems? 4. How to integrate (numerically) the hydro-chemo-mechanical (HCM) behaviour of fault zones in large-scale (reservoir or basin-scale) simulations? Regarding the first and second question, a geostatistical approach is adopted based on observations of fault structures at the Cirque de Navacelles. This site, located in the late Jurassic platform carbonates of Languedoc (southern France), can be considered a good analogue for CO2 storage reservoir. The third question is addressed at laboratory scale focusing on the CO2(aqueous)-induced effect on: i. the slow growth of cracks (subcritical fracturing) and their healing; ii. the degradation of mechanical properties such as fracture toughness or shear strength. Finally, the fourth question is numerically addressed by relying on: i. advanced meshing tools developed for converting complex geometries to finite element models; ii. analysis of fracture propagation condition within multiphase fractured porous media; iii. the rheological behavior derived from the experimental study.

Die interventionelle Behandlung der Mitralklappeninsuffizienz mit dem MitraClip®-Verfahren hat in den letzten Jahren in Deutschland und Europa eine rasche Verbreitung erfahren. Dabei hat die MitraClip®-Therapie offensichtlich das Potenzial, Hochrisikopatienten mit sekundarer – funktioneller – Mitralklappeninsuffizienz und deutlich reduzierter linksventrikularer Funktion wirksam zu behandeln. Daruber hinaus konnen auch erstmals Patienten mit primarer – degenerativer – Mitralklappeninsuffizienz und erhohtem Operationsrisiko oder sehr hohem Lebensalter einer im mittelfristigen Verlauf klinisch uberzeugenden Behandlung zugefuhrt werden. Gleichzeitig muss betont werden, dass sich dieser interventionelle Therapieansatz in einer fruhen Phase der klinischen Entwicklung befindet. Die umfangreichsten klinischen Erfahrungen mit der MitraClip®-Therapie liegen derzeit in einigen Zentren Deutschlands vor, die sich hier zur Ausarbeitung der vorliegenden Behandlungsempfehlungen zur Indikation und Durchfuhrung des MitraClip®-Eingriffs zusammengeschlossen haben. Diese Empfehlungen des Arbeitskreises der AGIK und der ALKK stellen damit eine Arbeitsgrundlage fur die zukunftige interventionelle Behandlung einer Mitralklappeninsuffizienz mit dem MitraClip®-Verfahren dar.

Intraprocedural assessment of mitral regurgitation (MR) is a challenging issue during the MitraClip procedure, which might influence not only the position but also the number of MitraClips implanted. Though transesophageal echocardiography (TEE) is the predominant tool used during the MitraClip procedure, MR assessment might be facilitated by a multimodality approach including continuous and simultaneous determination of left atrial and left ventricular (LV) pressure.86 consecutive patients (76.5 ± 8 years) who qualified for the MitraClip procedure were included into the study. In all patients, the multimodal assessment of MR (TEE, LV angiogram, TEE bubble evaluation, left atrial (LA) pressure =MitraScore) was performed after introducing the MitraClip guide catheter. In the first 42 patients (group A, no CAP), left atrial (LA) pressure (peak pressure of V-wave) was determined only before and after MitraClip implantation, whereas, in the subsequent 44 patients (group B, with CAP), continuous left atrial pressure monitoring (CAP) was performed.Patients with CAP (group B) had similar total procedural durations and no increase in the complication rate. MitraScore decreased from 10.5 to 3.5 in group A compared to 10.7 to *2.8 in group B (*P = 0.021 vs. group B). Whether the significant improvement of intraprocedural MR in group B translated into superior MR reduction in the conscious patient, was analyzed by transthoracic echocardiography (TTE) in a blinded fashion. Again MR reduction was significantly greater (P = 0.03) in group B (MR grade 2.8 to 0.9) as compared to group A (MR grade 2.8 to 1.3) and 2D vena contracta decreased from 0.54 ± 0.15 cm to 0.17 ± 0.10 in group B compared to group A (0.56 ± 0.19 cm to *0.23 ± 0.12; *P = 0.01 vs. group B).Multimodality assessment of intraprocedural MR supported by continuous left atrial pressure monitoring was associated with superior intraprocedural results translating into improved MR reduction also at the end of the hospital stay. © 2016 Wiley Periodicals, Inc.

The interventional treatment of mitral valve regurgitation by the MitraClip procedure has grown rapidly in Germany and Europe during the past years. The MitraClip procedure has the potential to treat high-risk patients with secondary mitral valve regurgitation and poor left ventricular function. Furthermore, patients with primary mitral valve regurgitation may be treated successfully by the MitraClip procedure in case of high surgical risk or in very old patients. At the same time it has been emphasised that the MitraClip interventional treatment is still at an early stage of clinical development. The largest clinical experience with the MitraClip procedure so far is probably present in some German cardiovascular centers, which here summarise their recommendations on the current indications and procedural steps of the MitraClip treatment. These recommendations of the AGIK and ALKK may present a basis for future development.

The impact of microscopic rock heterogeneities on elastic properties in an unconsolidated sandstone reservoir in the Orinoco Heavy Oil Belt in Eastern Venezuela is studied at 3 wells using rock physics models. Differences in grain and pore sizes and the presence of shale/clay and cement, lead to differences in elastic properties values at same porosity. This allows to detect two different consolidation levels in the reservoir: (1) unconsolidated and (2) weakly consolidated due to cement and smaller grains/pores, where the first one has better rock quality. Being able to detect the two consolidation levels proves the interest of rock physics modelling in our case as tool to relate geology and seismic and to perform a quantitative seismic interpretation.

Conventional reservoir characterization using geostatistical techniques to compute facies and porosity distribution usually begins from an estimation of the acoustic impedance. This impedance distribution is obtained using inversion technique as the stratigraphic inversion which works on prestack reflection seismic data [Tonellot & al., 2001]. The aim of this work is to take advantage of Amplitude versus Angle (AVA) inversion done after prestack depth migration to perform a depth domain impedance estimation constrained by AVA attributes. We propose to use geostatistical impedance simulation constrained by the migrated common image gather (CiG) and the skeleton of the structure obtained during the AVA inversion as well as the intercept and the slope sections.

Classically, the non stationary lithofacies distribution inside reservoirs is described by the 3D distribution of their proportions. This approach is very attractive because proportions have a physical meaning. Moreover their 3D distribution reflects the qualitative information coming from geology or the quantitative constraints derived from seismic attributes. In models such as the truncated gaussian, the proportions are directly used in the simulation process. In object-based models, such as the Boolean model, the problem is more complex because the proportions are the results of two sets of parameters: the object description (shape and dimensions) and their 3D distribution. The non stationarity in an object-based method can be reproduced either by using a non stationary object description or through a regionalized distribution of the objects. In this paper, we focus on the latter approach. The main contribution of the proposed method is the fact that the fit of the intensity point distribution is obtained globally in one computation step for any non stationary facies distribution. The interest is to constrain, a priori, the lithofacies simulation by a given 3D proportion distribution and not by convergence during the simulation process.

Geostatistics offers fast and flexible methods for reservoir studies and heterogeneity simulations. The starting point in every reservoir simulation process is the construction of the geological model. The type of geostatistical simulation used to reproduce the heterogeneity distribution depends on the sedimentary processes at the origin of the reservoir, and on the type of heterogeneity influencing the reservoir behaviour. This paper presents three outcrop examples that illustrate how to produce realistic geological simulations by optimising the simulation parameters, according to different geological settings. Both siliciclastic and carbonate reservoirs will be described.

P. Johann,^ Petrobras S.A.; F. Fournier, SPE, Institut Francais du Petrole; O. Souza Jr., Petrobras S.A.; R. Eschard, Institut Francais du Petrole; H. Beucher, Centre de Geostatistique de l'Ecole Nationale Superieure des Mines de Paris. Abstract A new methodology for 3-D stochastic reservoir modeling constrained by well and seismic data is applied to a pilot area, the Namorado turbidite giant oil field in the Campos basin. The stochastic modeling is based on a truncated Gaussian approach, with a non stationary algorithm using a 3-D matrix of lithotype proportions. The proportion matrix can he constrained by qualitative or quantitative seismic derived information. Qualitative information corresponds to vertical proportion curves, predicted at the trace locations, from seismic facies analysis. Quantitative information are estimates of lithotype thicknesses, over all the reservoir section, derived from calibration of seismic attributes. Whatever type of seismic constraints -qualitative or quantitative- their incorporation in the reservoir modeling led to a major improvement of reservoir heterogeneity representation, in the case of the Namorado field. The methodology is thus promising for other fields, particularly in turbidite environment. Introduction Reservoir stochastic modeling provides a good frame for integrating data of different sources and qualities. It leads to a more realistic 3-D reservoir image associated with risk assessment through an improved uncertainty representation. Well logs and core data provide detailed information about vertical variations of many reservoirs properties but they are restricted to regions adjacent to the borehole. Conversely, 3-D seismic data offer a dense coverage of the interwell areas and therefore should play a key role in describing reservoir heterogeneities. However, the integration of seismic data in reservoir stochastic models is still a challenge. Most of the time, the reservoir is described as a high resolution 3-D model of lithotypes and/or petrophysical properties, in which seismic information has to be incorporated. The difficulties for this incorporation are due to very different measurement scale for seismic and well information, and to often complex and non unique relationship between the useful reservoir properties and the acoustic or elastic parameters. Therefore, a direct incorporation of seismic information (amplitudes, acoustic impedances…) in the stochastic modeling is possible only in a limited number of cases, corresponding to simple (homogeneous) reservoirs. Unfortunately, it is not the frame of nearly homogeneous reservoirs for which seismic data is so crucial for bringing extra information between wells, since very small geological variations are expected in this case. In this paper, a conservative approach for integration of seismic in 3-D stochastic modeling is proposed. The key point is to break the problem in two steps. Firstly, the seismic information is turned into average geological information, directly related to the modeling process. Secondly, this information is accounted as global and soft constraints in the modeling. This approach allows to overcome both difficulties of scale and indirect relationship between seismic data and reservoir properties to simulate. Two possibilities are proposed for extracting the soft geological information contained in the seismic data. The first one, based on seismic facies analysis, provides a qualitative interpretation of the reservoir interval in terms of geological behavior. The second one uses statistical calibration techniques to derive estimates on average reservoir properties (quantitative information). Both kind of information -qualitative and quantitative- are integrated in the 3-D modeling of lithotypes using a non stationary truncated Gaussian approach (Figure 1). P. 51

It has been established in previous papers, that the Truncated Gaussian Random Method is a very efficient tool for simulating sedimentary images in a fluvio-deltaic environment. Moreover, this method allows the introduction of geological knowledge different from the lithofacies, by means of threshold variations 3D matrix. However, there are still some cases which cannot be easily solved by the current Truncated Gaussian Random Function approach, especially when the whole lithofacies cannot be rigorously ordered. It is thus possible to generalize the use of the Truncated Gaussian Random Function by introducing several Gaussian Functions. This allows lithofacies simulations of reservoirs where several sequences overlap. In this paper, we show how to apply this method using mainly two Gaussian Functions when at least three lithofacies must be simulated. Firstly, the linear model of coregionalisation is used to generate correlated Gaussian Functions and the effect of this correlation is presented. Secondly, we use uncorrelated functions to show the effect of the simulation parameters, especially focusing on the anisotropy effect. Thirdly, we present a more complex type of truncation. In conclusion, we begin a discussion on the choice of the simulation parameters.

The objective of the Geoscience Project JOUF-0034, which involved three European oil companies and a number of research institutes located in four EC countries, was to calibrate probabilistic representations of reservoir heterogeneities to actual geological field observations. Three outcropping formations, the deltaic Roda sandstone (Spain), the alluvial fan system of Cajigar (Spain) and the storm deposits of Poulseur/Compagnie du Bois d'Anthisnes (Belgium) were the selected geological objects. For the three sites, the approach was similar: first, extensive geological field work led to the construction of a detailed geological model and to the acquisition of a number of geological field sections on each formation. The sections were then digitized and used as control points in the construction of a ‘reference model’ of each geological formation. The three models probably constitute the most significant results of the project. They describe, as accurately as possible, the geological heterogeneities of each formation at the reservoir scale. The reference models are three-dimensional for Roda and Cajigar, and two-dimensional for Poulseur/CBA. For Roda (and to a lesser degree Cajigar) the last step of the study consisted of simulating oil field appraisals by assuming that only a small number of stratigraphic field sections (or ‘wells’) were known, and reconstructing by geostatistical techniques the architecture of the reference model. This led, for the Roda study, to the development of a novel ‘random genetic simulation’ technique for reconstructing the architecture of deltaic prograding sandbodies. A number of conclusions were drawn from the three studies. The 3D approach proved to be more rigorous than standard 2D correlations of outcropping formations, because it imposes constraints on the spatial consistency of the models. The two-sided interaction between sequence stratigraphy considerations and the analysis of the reference models also proved very fruitful for validating the geological assumptions and understanding their impact on the distribution of heterogeneities. It is worth noting that quantitative geological modeling could only be achieved through a multi-disciplinary approach by geologists and geostatisticians.

The truncated gaussian method [6] [8] has been widely used in the past in order to simulate indicators. In this paper we investigate the potential and limitations of this method, from a geostatistical point of view and also from a practical one. First we present the method in detail including the hypotheses behind it. In particular we show that this method ensures consistency for the model in terms of the indicators variograms and cross variograms. Examples of the types of variograms that can and cannot be fitted using this method are presented. Then we discuss how to take into account vertical non stationarity for the indicators, as this seems to be the usual case (due to sequential evolutions in a sedimentary unit). This point will be illustrated via several examples. We then explain how the method can deal with a complex 3D non stationarity, and discuss the practical problems of using it in this case.

When studying the geometry of petroleum reservoirs, we have to integrate different kinds of data (wells and seismic) as well as geological knowledge. Usually, wells show the fine vertical variation of lithofacies, but are less precise about horizontal variations. On the another hand, seismic data give a good idea of the horizontal evolution but we lose information on the vertical variability. A realistic reservoir model has to take this into account.

Abstract A method for evaluating the production scenarios in the delineation phase of an oil field is described, and illustrated with a synthetic example build from a Mesa Verde (Colorado) area outcrop. At delineation time, only a few wells and some geophysical surveys are available for reservoir characterization. The geologist analyses these data, and determines some major characteristics of the deposition system as its type, its direction, etc. This interpretation is then quantified so as to be used as the input of a geostatistical simulation model, in terms of lithofacies proportion curves, and variogram function parameters. This quantification is not unique, and the geologist provides ranges for each parameter. The geostatistical simulator gives several images, with different parameters varying in the selected ranges. A first investigation among these images is performed by looking at the volume of reservoir connected to the producing or injecting wells, for various wells spacing. Then, these images are translated into petrophysical description, allowing to perform oil petrophysical description, allowing to perform oil recovery calculations, for the selected images. Finally, an estimation of the oil production for different development scenarios, taking into account uncertainties is performed. This methodology is possible thanks to a geostatistical simulation model enabling integration of geology and reservoir engineering. The geostatistical simulation model is a tool for translating geological knowledge into parameters manageable for reservoir engineers. The proposed methodology allows to make better decisions in the delineation phase, as impact of uncertainty can be more easily computed. The availability of an integrated model, avoiding painful data handling (petrophysical data attribution, upscaling), is an important point. Introduction 1-1 THE PROBLEM Once an exploration well has shown the presence of hydrocarbon bearing formations, a presence of hydrocarbon bearing formations, a program of delineation well drilling begins. That program of delineation well drilling begins. That program aims at determining the major features of program aims at determining the major features of the discovered field, in order to be able to appraise its economical value. These features are:–The type of trap (structural, stratigraphical, by fault, etc).–The geometry of the reservoir (shape, interconnectedness, volume of porous and permeable reservoir).–The petrophysical characteristics of the reservoir.–The fissuration, if any. P. 209

Abstract An accurate understanding of the internal architecture of a reservoir is required to improve oil recovery forecasts. This article describes a software which gives 3D images of this architecture using conditional geostatistical simulations and provides tools to study the influence of these lithological descriptions on fluid flow behavior. This software establishes the link between wells data and fluid flow reservoir simulators. Each step of this interactive and graphic system is explained here:–geological and geostatistical analysis to characterizea suitable model for the following steps,–conditional geostatistical simulations giving a lithological description of the internal heterogeneities onhigh resolution grids,–quantification of the reservoir assigning petrophysical values to each lithofacies grid cell (porosity and absolute permeability tensor),–scaling up methods computing in a cost effective way the averaged petrophysical values associated to reservoir simulator grid cells. This new software concept which integrates multidisciplinary methods helps production geologists, geostatisticians, applied mathematicians and reservoir engineers to work in the same environment. Introduction Current efforts to maximize oil production are becoming increasingly dependent on geological reservoir characterization. A major reason for poor recovery efficiency is the presence of geological heterogeneities which cause highly non-uniform fluid flow patterns and incomplete oil drainage. So reservoir engineering studies should take into account as much available information as possible in order to improve the production forecasts. These extra data come from several disciplines and in practice, it is important to have a software which can handle them effectively. The Heresim Group is working on a methodology to improve the internal architecture of reservoirs in fluvio-deltaic dept sits using geostatistics. The application of these methods undergoes the development of integrated softwares. A 2 dimension version of the software has been developed and here we describe the 3 dimension one: HERESIM 3-D. The aim of this software is to start with well data and produce results which are directly usable by reservoir fluid flow produce results which are directly usable by reservoir fluid flow simulators, taking into account the geological interpretation of the reservoir. THE SOFTWARE This software is designed as an interactive program and relies on an existing package for data handling called "Magma". The Magina data base has been especially developed to deal with well data and big grid data sets. It is very important to be able to perform complex selections on the data to get statistics quickly and to store the huge output data sets (millions of cells) in an efficient way. HERESIM 3-D is provided with modern tools like on-line help and journal files and can be run on numerous types of computers. Many of the outputs are color graphics and need a graphical terminal for convenience. The software is divided into five parts:–Data read and geological definition–Statistics–Lithofacies simulation and visualization–Petrophysical value assignation–Mesh for reservoir simulators P. 171

Abstract This paper gives the geological aspect of a 3-D study on fluvio-deltaic sedimentary bodies and corresponding 3-D conditional simulations obtained by geostatistical methods. It is the continuation of paper SPE 16752 and 16753 (Dallas, 1987). It describes the new sedimentological interpretation of the Scalby formation (U.K.) from the core-drill data, the different correlations performed between the core-drills, the quantification in terms of proportion curves and of variograms of lithofacies sets - and at last some conditional simulations, The image of the cliff is described with the topographical corrections. This new image allows establishing the true correlation with the eleven core-drills located just behind the cliff, and to carry out the accurate structural analysis - in the geostatistical sense of the term - required for the simulations. Henceforth, the core-drill study shows that the evolution of the system and the deposit environment are somewhat different from those deduced from the field data. Therefore, there exists a marine influence in the basal terms, and the unconformity separating the major units is significant and probably regional. However, the field data remain essential for the geostatistical study. The upper unit is composed of multistoried and highly sinuous channels deposited in a typical fluviodeltaic environment. The lower unit is principally fluvial-dominated but it has been influenced by the tides, The well-to-well correlations show that the overall geometry is of a sand-sheet type. The interval are more or less of the same thickness ; this fact, together with the low rate of sedimentation and the low thickness/lateral extension ratio of the terms suggest low subsidence and high lateral divagations of the distributaries. Correlations in terms of lithostratigraphy, lithology, porosity and permeability have been made between the porosity and permeability have been made between the core-drills in the grid where the distance was progressively reduced. The illustrations from the correlation progressively reduced. The illustrations from the correlation given in this paper emphasize the lateral variations in several parameters (facies, petrophysical…) between wells in the same lithostratigraphic unit over short distances. Interpreted geological data have been digitised and then quantified. This quantification is represented by vertical proportion curves and by variograms which are the input parameters for the calculation of the simulations. 2 and 3-D conditional simulations of the studied reservoirs are carried out and then analysed. These random set conditional simulations are obtained by an original method elaborated by our IFP-CG group. In this paper, we show the influence of the input parameters on the results. These parameters have been parameters on the results. These parameters have been relatively easily fitted due to a large amount of information. The obtained simulations then display an aspect very similar to that of the digitised cliff. The horizontal ranges have an influence over the continuity restoration. Thus a large range gives a strong continuity of the simulated image, while a short range reduces the size of the simulated sedimentary bodies. The ranges are calculated and then fitted using available data. When these data are insufficient, other "a priori" information is introduced. priori" information is introduced. The vertical proportion curves of the different facies plays an important part in the lithofacies plays an important part in the lithofacies distribution. These curves are easily calculated from the coredrills. P. 463

The validity of dynamic simulations carried out by reservoir engineers depends on the reservoir model used. The continuity of the reservoir layers is poorly known because of the small number of drillholes available and the distance between them. The aim of this study of an outcrop, is to develop a method for simulating the geometry of the reservoir. The sedimentological study provides an image of this outcrop with 4 lithofacies. The interpretation of this image as a realisation of random sets obtained by truncating Gaussian functions leads to a simulation process and a structural analysis method. This process is efficient provided that factorizable covariances of an exponential type, suited to describe sedimentary processes, are used. The 3-D covariance models are fitted to the data from the coredrills carried out behind the cliff. Then simulations of the whole reservoir are made.

Abstract Quantitative methods taking into account the sedimentological characteristics will answer the needs of reservoir engineers. We propose here a geostatistical method for the conditional modelling of the facies of a sedimentary fluvio-deltaic series. This model was elaborated jointly by I.F.P. and the Paris School of Mines, with the aim of modelling reservoir heterogeneities. From the sedimentological study contained in the paper by C. Ravenne et al., we present several simulations, conditioned by "drill-core" taken from the outcrop. The block permeabilities are then calculated from the values given to the facies. Introduction Reservoir engineers have, for a long time, been asking what type of models could be entered into reservoir simulators. The geological models that are normally used are essentially qualitative and so it is difficult to numerize them, except by correlating the drillholes facies, which is not always self evident. This often leads to models with too many constraints for simulating reservoirs. Their dynamic behaviour worsens considerably going from very continuous layers of sandstone to disseminated lenses. (Fig. 1). This raises the question of how to characterize the geometry of the sandstone given the drillhole data, the geologist's interpretation and also other measurements (e.g. seismic recordings), and how to model the reservoir levels to suit this shape. As well as this, the models must match the lithology along the drillholes. In this article, we present a method for conditionally modelling the lithology which is designed for sedimentary processes. This approach was tested using the geological section of a cliff-face in Yorkshire (England) which shows a fluvio-deltaic environment similar to some of the levels in the Brent formation in the North Sea. A detailed description of the geology of the cliff-face studied and of the approach used in this project have been presented by Ravenne et al. Here we shall only consider the problem of modelling random sets by using a probabilistic method for representing the spatial distribution of the facies (sandstone, shaly sandstone, shale) in a heterogeneous reservoir. Before presenting the method, we review the main procedures for modelling random sets, that are used in the petroleum industry. REVIEW OF THE EXISTING METHODS Boolean Sets A simple way is to consider a heterogeneous medium as consisting of sandstone lenses in a shale matrix (or vice versa). Boolean sets (Matheron, Serra, Jeulin) are a mathematical way for modelling this type of deposit, that has been used for many years in other fields (Fig. 2). This method consists of putting lenses of a predetermined shape (e.g. ellipses or rectangles) at random points in the domain under study (i.e. the points are statistically uniformly distributed in space). Lenses are not correlated. The advantage of this approach is that it is easy to use in 2D or 3D spaces. It only depends on a few parameters: the number of seed points per unit space (called density), the shape of the lenses (fixed or variable), their size and orientation. The model is very flexible. The parameters can be modified locally in order to reproduce the real phenomenon more accurately. Clearly the more complicated the model is, the more parameters there are to fit but this can be overcome by fitting them by trial and error. P. 591^