- Home
- Conferences
- Conference Proceedings
- Conferences
Third EAGE CO2 Geological Storage Workshop
- Conference date: 26 Mar 2012 - 27 Mar 2012
- Location: Edinburgh, UK
- ISBN: 978-94-6282-054-8
- Published: 26 March 2012
1 - 20 of 46 results
-
-
Invited Keynote: From Longannet to Peterhead - the Goldeneye CCS project Continues to Move Forward
By P. GarnhamOver the past four years a consortium of Shell, National Grid and ScottishPower has been working together, sponsored by the UK Government to try to develop a commercial scale CCS project based on emissions from Longannet Power Station (coal-fired, and operated by ScottishPower) with storage in the Goldeneye reservoir
-
-
-
On the Use of Contact Angle Measurements to Determine the Wetting Properties of CO2
Authors J.R. Mills and M. SohrabiThis work presents new findings on the interaction of CO2-brine at reservoir conditions using the drop shape analysis method to determine contact angle and interfacial tension. Water-wet behaviour was observed at subcritical and supercritical conditions on a representative selection of real reservoir minerals. This study addresses fundamental physical properties of rock-fluid interactions pertaining to fluid flow and trapping at the pore-level.
-
-
-
Effect of Burial Depth on Deformation and Storage Capacity of Sandstone Reservoirs
By A. TorabiThe present study investigates the effect of consolidation (burial depth) on the deformation and fluid flow behaviour of sandstone and its possible effect on the storage capacity of sandstone reservoirs. Sandstones with different degrees of consolidation from a variety of burial depths have been studied through in-situ measurements in the field and further analysis of the samples. There is a correlation between deformation mechanism and consolidation of sandstone. Unconsolidated sandstones that deform at shallow burial depth show a weak cataclasis, while well-consolidated and cemented sandstones deform mainly by fracturing. The deformation mechanism will affect the fluid flow within the rocks. Permeability reduction from host rock to fault rocks is significant within consolidated sandstone. The slip surfaces show lower permeability, while fault lenses present higher permeability values when compared to other fault related rocks. This is due to the fact that deformation is localized within the slip surfaces, while fault lens partly includes remnants of undeformed host rock. The higher capillary pressures in some of the fault rocks may contribute to trapping of CO2 through capillary forces, although, low permeability and high capillary pressure usually hamper connectivity and fluid flow within the reservoirs.
-
-
-
Impact of Top-reservoir Morphology on CO2 Sequestration
Authors J. Tveranger, P. Dahle, H. Møll Nilsen, A.R. Syversveen, J.M. Nordbotten, P. Abrahamsen and K.A. LieModels used for evaluating CO2 plume behaviour in the subsurface often employ simplified geological reservoir descriptions. Experiences from the petroleum industry show, however, that geological heterogeneities significantly influence fluid flow. The present study addresses the need for evaluating the impact of realistic geology on CO2 behaviour in the subsurface. We here demonstrate the effect of adding realistic complexity to the top reservoir morphology. A sensitivity matrix consisting of combinations of depositional and structural irregularities creating relief along the top of a reservoir was set up and the resulting models run in a fluid flow simulator monitoring CO2 plume dynamics. Results demonstrate the interaction between specific geological features and resulting plume behaviour and added retention capacity. Our study highlights the need to include realistic geology in models forecasting migration behaviour in subsurface reservoir.
-
-
-
Capacity in a Depleted Gas Field - Relative Permeability Bites Back
Authors C. Annia, O. Tucker, C. Thompson and S. GoodyearStorage capacity is an estimate of the maximum amount of CO2 that can be stored in geological formations. All methodologies used to calculate it start with an estimation of the pore space available for CO2 injection based on mapped pore volume or inferred from production history. For depleted hydrocarbon fields the volume of hydrocarbons produced is known.
-
-
-
Case Studies for Monitoring of CO2 Storage Sites, based on Ground Deformation Monitoring with Radar Satellites
Authors J. Granda, A. Arnaud, B. Payàs and B. LecampionInSAR (Interferometry for Synthetic Aperture Radar) technology is a spaceborne measurement method that uses radar satellite images to detect and measure ground deformation with millimetric precision. Measurements are taken remotely from space, making this an appropriate tool for measuring ground motion in difficult to reach remote areas and in almost all weather conditions, during day or night. The Stable Point Network (SPN) is an advanced differential interferometric chain which was developed by Altamira Information in order to process several raw radar images to achieve millimetric ground motion measurements. Results are provided in GIS format and can be received and analysed by CO2 reservoir engineers remotely without the need for site visits. International case studies will be presented for three CO2-storage sites. These sites have been selected because they differ in the several criteria: Site conditions (climate, surface …), stage of CO2-injection, amount of detected ground motion, density of measurement points and cause of ground motion. To summarise, ground motion studies using InSAR technology contain valuable information for pore pressure behaviour monitoring of CO2 storage sites, especially when InSAR ground motion measurement results are inverted and used for reservoir management and history matching of geo-mechanical models.
-
-
-
Monitoring of the In Salah CO2 Storage Site (Krechba) Using Microseismic Data Analysis
Authors V. Oye, P. Zhao, D. Kühn, K. Iranpour, E. Aker and B. BohloliMicroseismic data recorded at the In Salah CO2 storage site (Krechba), Algeria has been analysed and interpreted. Based on the results of the single observation well and detailed information of the subsurface geological and geophysical model, we conducted a network design for improved location capabilities of future microseismic events.
-
-
-
Baseline of Soil-Atmosphere CO2 Flux in the Hontomin Site (Burgos, Spain)
Authors L. F. Mazadiego, F. Grandia, J. Elio, B. Nissi, O. Vaselli, M. Ortega, J. Caballero, E. Vilanova, E. Chacón and J. LlamasCO2sc is planned to be injected in 2013 at the Hontomín site (Spain) as a part of the EC-funded OXYCFB300 project. The objectives of this project are: the development of knowledge, methodologies and technologies for industrial application of geological storage of CO2; the demonstration that industrial activity is feasible and safe; provision of support to the regulatory authority; and the promotion of scientific and technological training in CCS. During the stages of selection and characterization activities have been conducted on structural geology, hydrogeology and hydrogeochemical, geophysics, laboratory experimentation and modeling of behavior and injection of CO2, natural gas emissions, and risk analysis. CO2 is going to be injected in a saline reservoir (1500 m depth) hosted by Lower Jurassic limestones and sealed by Lower Cretaceous clay formations. As part of the site characterization, baseline of CO2 flux in the soil-atmosphere interface has been determined. This is an important task to detect leakage in the reservoir during the operational stage and post-closure of the storage. In case of failure of the seal, CO2 fluxes in conduits such as wells or faults are expected to significantly increase, and they can be easily detected by comparing them with those from the pre-injection stage.
-
-
-
Using an Old Underground Blowout as a Proxy for CO2 Leakage Scenarios
More LessBased on seismic data acquired prior to an underground blowout in 1989, we find that it is reasonable to assume that there has been some gas migration into shallower sediments over a time period of 20 years. By studying the seismic datasets (several 2D lines and one 3D) acquired over this area, we can learn something about how fast gas migrates through shallow sediments close to the seabed. Since CO2 is denser and will probably flow slower than gas, we think it is possible to use this example as a proxy to estimate the lower bound for vertical transit times of CO2 through shallow sediments of the type we are studying. This knowledge we believe might be of importance in risk assessment associated with underground storage of CO2. However, the reservoir pressure and temperature conditions (that vary with depth) dictate the CO2 behaviour, whether it is supercritical with liquid-like densities or with gas-like viscosities. It is important to stress, therefore, that there are significant differences between CO2 in a supercritical phase and the assumed gas associated with an underground blow out from an oil well.
-
-
-
Monitoring of Leakage from CO2 Stores in Shallow Groundwater Aquifers – Lessons Learned from Natural Analogues
By F. MayIn the case of leakage from a deep aquifer storage, ascending saline formation waters and CO2 can mix with fresh waters and react with shallow aquifer rocks. These processes reduce concentrations of chemical species in contaminant plumes and cause overlapping concentration ranges of chemical elements with back ground waters. Some examples are presented from areas where natural CO2 and carbonic water discharge together with fresh groundwater. The main reasons of uncertainty in leakage quantification are: natural variability of background waters, chances of plume detection in thick alluvial aquifers with high groundwater flow rates and the calculation of mass balances from geochemical point data obtained from limited numbers of observation wells. These inherent uncertainties have to be taken into account in the preparation of risk management and monitoring plans for groundwater protection, e.g. the choice of indicative chemical species and the definition of threshold levels for actions to be taken.
-
-
-
Time Lapse Seismic Interpretation of CO2 Storage at the Snøhvit Field
More LessBased on time lapse amplitude variation with offset (AVO) data we present one possible interpretation of fluid and pressure effects due to CO2 injection at the Snøhvit field.
-
-
-
MMV Plan
Authors I. Susanto, P. Wood, W. Berlang and E. MackieFor each CO2 storage project, a Measuring Monitoring and Verification (MMV) plan is created that describes how the operator aims to ensure public and environmental safety, verify storage performance and containment and, in case of leakage, quantify the amount leaked back to the atmosphere. To deliver the MMV aims, effective monitoring technologies have to be selected to address the site-specific risks. In this article, this MMV design approach is applied to the Goldeneye field, a gas reservoir, located 101km offshore North-East of Aberdeen, Scotland.
-
-
-
An Open Source Numerical CO2 Laboratory
Authors K.M. Flornes, K.A. Lie, H.M. Nilsen, O. Saevareid and B. FlemischNumerical simulation tools are essential in the assessment of potential CO2 storage sites. We will present a new suite of open source simulation tools built on modern software principles. The simulation suite is the result of a collaborative effort by several research groups in Norway and Germany. The goal is to bridge the gap between academia and industry and accelerate the transfer of new methods and modeling options. A set of validation studies using synthetic CO2 benchmark problems and real data from the Utsira injection site will be presented.
-
-
-
Pore Scale Modelling of CO2 Storage in the Utsira Formation
Authors T. Ramstad, H.G. Rueslåtten and E. LindebergDigital pore scale images of the reservoir rocks from the Utsira formation have been modelled. The Utsira Formation on the Norwegian Continental Shelf that is already being used for CO2 sequestration. This is a saline sand aquifer of Miocene to early Pliocene age, which is covered by some 700 meters of shales and sands. The aquifer is large and CO2 is being injected into the aquifer at a depth of 1012 meters below the sea floor by a highly deviated 3 km long well from the Sleipner Field. Direct dynamic CO2/water simulations have been conducted with all relevant fluid and flow properties. From these simulations steady and un-steady state constitutive relations (relative permeability, end-point saturations) are obtained. Clear flow rate and viscosity effects are revealed from these data, which again affects the storage capabilities of the reservoir rocks.
-
-
-
The Effects of CO2 on Reservoir and Seal Quality during Storage in Depleted Rotliegend Gas Fields in NE Netherlands
Authors P. Bolourinejad and M.A. HerberThe effects of CO2 storage on reservoir quality and caprock integrity have been studied for several potential storage sites in northeast of the Netherlands. These fields have the Permian Rotliegend as the reservoir, overlain by Zechstein carbonates, anhydrites and salt. Long term laboratory experiments were carried out in high pressure/ temperature condition on reservoir and seal samples in the presence of CO2, methane and brine. The results were then compared with the predictions from model simulations. Experiments and modeling results are in good agreement with respect to the nature of mineral dissolution and precipitation. However, deviation between modeling and experiment is observed with regard to the magnitude and time scale of changes in mineral dissolution and precipitation. In many observed experimental cases, both processes appear to occur more aggressively (i.e. faster and stronger) than predicted by the model. The probable reason for this deviation is uncertainty in the key modeling parameters such as activation energy and surface area of minerals. Exact knowledge of the brine composition is also essential.
-
-
-
History-matching of CO2 Flow at Sleipner – New Insight based on Analyses of Temperature and Seismic Data
Authors C. Hermanrud, H.M. Nordgård Bolås, G.M.G. Teige, H.M. Nilsen and A.F. KIærHistory matching of layer 9 of the Utsira Formation in the Sleipner area has so far been problematic, but could be achieved it higher CO2 temperature than has previously been estimated are invoked. Such high temperatures can to some extent be justified from hithero unknown DST measurements. Furhtermore, heat exchange between warm injected CO2 and the colder reservoir can be significant. Such heat exchange may possibly explain the discrepancy between modelled and observed CO2 fow in the Utsira Formation.
-
-
-
CCS in the Goldeneye Field, UK - A Geomechanical Assessment of Containment
Authors J. M. Davison, S. de Vries, J. Ita, L. Acevedo, A. Shinde, P. Fokker and R. WentinckFor any CCS project, geomechanics plays a key role in determining the containment of the injected CO2. The high potential routes for loss of containment include fracturing the caprock and/or migration along discontinuities through the caprock. Leakage processes are dominated by the in-situ stresses, formation pressures, injection pressures and temperature of the reservoir, all of which vary with time. Whilst injection of gas and fluids in subsurface formations is common practice, we identify key geomechanical challenges associated with CCS projects. These key challenges are explained within the context of the Goldeneye CCS project. Geomechnaical modelling was conducted for assurance of containment for the full life-cycle of the field. Numerical tools have been used to evaluate caprock integrity, reservoir deformation, fault stability and the impact of thermal cooling in terms of fracturing of the reservoir as well as the caprock. We also discuss the impact of thermal cooling adjacent to the injection well and the impact this could have on development of micro-annuli as potential leakage pathways. The results of the geomechanical analysis support injection of CO2 into the depleted Goldeneye reservoir which provides reliable containment over the planned injection period, as well as long-term sequestration within the storage complex.
-
-
-
Reactive Transport Modeling for CO2 Storage in a Depleted North Sea Gas Field
Authors J. Snippe, L. Wei, C. Lovelock and O. TuckerThe key subsurface selection criteria for a CO2 storage candidate are capacity, injectivity and containment. There are many factors that influence these selection criteria. The factor addressed in this paper is the geochemical interaction between CO2 and the rock minerals. Each of the criteria can be affected by these interactions. For Goldeneye, a depleted gas reservoir in the Central North Sea, we have simulated the potential geochemical interactions with and without coupling to fluid flow. For the standalone interactions we used a standard geochemical modeling package (PHREEQC), using dissolution/precipitation rate formulas. For the coupled interactions we used our in-house reservoir simulator coupled to PHREEQC. The reservoir simulator was run in Equation of State mode so that it takes into account the phase behaviour between the gas (including CO2 – hydrocarbon mixing), oil (thin oil rim) and water. We also considered diffusion models through the caprock. The conclusion is that for Goldeneye the CO2-induced reactions tend to decrease porosity in the caprock as well as in the reservoir. Therefore it is considered unlikely that the geochemical interactions would create leak paths in the caprock. The porosity decrease in the reservoir is not likely to have a significant impact on injectivity.
-
-
-
The Importance of Mineral Surface Areas Exposed to Open Pores in Rotliegend Sandstones for Modelling CO2 Water-rock Interactions
Authors S. Waldmann, A. Busch, L. Wei, K. van Ojik and R. GauppRotliegend reservoir rocks from the northern Netherlands were analysed in terms of mineralogical features, diagenetic mineral types and mineral surface areas which are exposed to open pores (effective mineralogy). The consideration of the effective mineralogy in comparison to the volumetric bulk rock composition of sandstones and the integration into CO2-water-rock simulation has shown that the mineral reactions are sensitive according to the initial data set. For the test scenario the results show that during CO2 storage especially long-term carbonate and silica reactions are affected. For the effective mineralogy data Mg-smectite stays in equilibrium with the solution which is caused by a higher initial amount of hematite and the release of iron for siderite precipitation. This reaction lowers the bicarbonate content in the solution and forces dolomite and ankerite to dissolve consequently. On the other hand Mg-smectite is unstable and carbonate minerals stay in equilibrium at the end of the simulation according to the volumetric mineralogy data.
-
-
-
Business as Unusual - The Key Subsurface Challenges in Sequestration in a Depleted Gas Field
Authors O. Tucker, C. Lovelock, L. Acevedo and M. KosterWe are all well versed in developing oil and gas fields: understanding their key uncertainties and what is important to ensure a successful and safe development.
-