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Book chapterJackson MD, 2015,
Tools and Techniques: Self-Potential Methods
, Treatise on Geophysics: Second Edition, Pages: 261-293The self-potential (or spontaneous potential) (SP) method comprises the passive measurement of electric potential at the ground surface and in boreholes. SP methods have a number of advantages over other geophysical techniques: They are often cheaper and quicker to implement, requiring only a pair (or more) of suitable electrodes and a high-impedance voltmeter, and data can be obtained over large regions with dense sampling in both space and time. Moreover, SP anomalies are often directly related to the process of interest, such as changes in groundwater flow, chemistry, and/or temperature. The disadvantages largely lie in interpreting the data, which can be more challenging than other geophysical techniques. Similar to gravity and magnetic methods, SP measurements are purely passive, so there is often no way of adjusting source parameters to help identify signals of interest. Moreover, SP signals arise from a variety of sources, and distinguishing these can be challenging. Traditional SP surveys for mineral exploration, and borehole SP logs, have been interpreted qualitatively or semiquantitatively; however, a new generation of inversion techniques for SP measurements are now becoming available, driven by improved understanding of the underlying physical processes and increased computing power. Furthermore, the range and number of applications of the SP methods have rapidly increased in recent years.
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Conference paperJackson MD, Hampson GJ, Rood D, et al., 2015,
Rapid reservoir modeling: Prototyping of reservoir models, well trajectories and development options using an intuitive, sketch-based interface
, Pages: 829-845Constructing or refining complex reservoir models at the appraisal, development, or production stage is a challenging and time-consuming task that entails a high degree of uncertainty. The challenge is significantly increased by the lack of modeling, simulation and visualization tools that allow prototyping of reservoir models and development concepts, and which are simple and intuitive to use. Conventional modeling workflows, facilitated by commercially available software packages, have remained essentially unchanged for the past decade. However, these are slow, often requiring many months from initial model concepts to flow simulation or other outputs; moreover, many model concepts, such as large scale reservoir architecture, become fixed early in the process and are difficult to retrospectively change. Such workflows are poorly suited to rapid prototyping of a range of reservoir model concepts, well trajectories and development options, and testing of how these might impact on reservoir behavior. We present a new reservoir modeling and simulation approach termed Rapid Reservoir Modeling (RRM) that allows such prototyping and complements existing workflows. In RRM, reservoir geometries that describe geologic heterogeneities (e.g. faults, stratigraphic, sedimentologic and/or diagenetic features) are modelled as discrete volumes bounded by surfaces, without reference to a predefined grid. These surfaces, and also well trajectories, are created and modified using intuitive, interactive techniques from computer visualization, such as Sketch Based Interfaces and Modeling (SBIM). Input data can be sourced from seismic, geocellular or flow simulation models, outcrop analogues, conceptual model libraries or blank screen. RRM outputs can be exported to conventional workflows at any stage. Gridding or meshing of the models within the RRM framework allows rapid calculation of key reservoir properties and dynamic behaviors linked with well trajectories and development plans.
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Journal articlePavlidis D, Gomes JLMA, Salinas P, et al., 2015,
Numerical modelling of debris bed water quenching
, IUTAM SYMPOSIUM ON MULTIPHASE FLOWS WITH PHASE CHANGE: CHALLENGES AND OPPORTUNITIES, Vol: 15, Pages: 64-71, ISSN: 2210-9838 -
Journal articleLeinov E, Jackson MD, 2014,
Experimental measurements of the SP response to concentration and temperature gradients in sandstones with application to subsurface geophysical monitoring
, JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, Vol: 119, Pages: 6855-6876, ISSN: 2169-9313- Author Web Link
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- Citations: 22
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Journal articleSolano JMS, Jackson MD, Sparks RSJ, et al., 2014,
Evolution of major and trace element composition during melt migration through crystalline mush: Implications for chemical differentiation in the crust
, American Journal of Science, Vol: 314, Pages: 895-939, ISSN: 0002-9599We present the first quantitative model of heat, mass and both majorand trace element transport in a mush undergoing compaction that accounts forcomponent transport and chemical reaction during melt migration and which isapplicable to crustal systems. The model describes the phase behavior of binarysystems (both eutectic and solid solution), with melt and solid compositions determinedfrom phase diagrams using the local temperature and bulk composition. Traceelement concentration is also determined. The results demonstrate that componenttransport and chemical reaction generate compositional variation in both major andtrace elements that is not captured by existing geochemical models. In particular, wefind that, even for the simplest case of a homogenous, insulated column that isinstantaneously melted then allowed to compact, component transport and reactionleads to spatial variations in major element composition that, in this case, producesmelt that is more enriched in incompatible elements than predicted by batch melting.In deep crustal hot zones (DCHZ), created by the repeated intrusion of hot, mantlederivedmagmas, buoyant melt migrating upwards accumulates in high porosity layers,but has a composition corresponding to only a small fraction of batch melting, becauseit has locally equilibrated with mush at low temperature; moreover, melt migration andchemical reaction in a layered protolith may lead to the rapid formation of highporosity melt layers at the interface between different rock compositions. In both ofthese cases, the melt in the high porosity layer(s) is less enriched in incompatible traceelements than predicted if it is assumed that melt with the same major elementcomposition was produced by batch melting. This distinctive decoupling of major andtrace element fractionation may be characteristic of magmas that originate in DCHZ.Application of the model to a number of crustal systems, including the Ivrea-Verbanozone, the Rum layered intrusion, and the Hol
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Journal articleDeveugle PEK, Jackson MD, Hampson GJ, et al., 2014,
A comparative study of reservoir modeling techniques and their impact on predicted performance of fluvial-dominated deltaic reservoirs
, AAPG BULLETIN, Vol: 98, Pages: 729-763, ISSN: 0149-1423- Author Web Link
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- Citations: 26
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Journal articleFitch PJR, Jackson MD, Hampson GJ, et al., 2014,
Interaction of stratigraphic and sedimentological heterogeneities with flow in carbonate ramp reservoirs: impact of fluid properties and production strategy
, Petroleum Geoscience, Vol: 20, Pages: 7-26, ISSN: 1354-0793It is well known that heterogeneities in carbonate reservoirs impact fluid flow during production. However, few studies have examined the impact of the same heterogeneities on flow behaviour with different fluid properties and production scenarios. We use integrated flow simulation and experimental design techniques to investigate the relative, first-order impact of stratigraphic and sedimentological heterogeneities on simulated recovery in carbonate ramp reservoirs. Two production strategies are compared, which promote dominance of either horizontal or vertical flow.We find that the modelled geology is more important than the simulated fluid properties and production scenarios over the ranges tested. Of the heterogeneities modelled here, rock properties and stratigraphic heterogeneities that control reservoir architecture and the spatial distribution of environment of deposition (EOD) belts are important controls on recovery regardless of the production strategy. The presence of cemented hardground surfaces becomes the key control on oil recovery in displacements dominated by vertical flow. Permeability anisotropy is of low importance for all production strategies. The impacts of stratigraphic heterogeneities on recovery factor and water breakthrough are more strongly influenced by fluid properties and well spacing in displacements dominated by vertical flow. These results help to streamline the reservoir modelling process, by identifying key heterogeneities, and to optimize production strategies.
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Journal articleDilib FA, Jackson MD, 2013,
Closed-Loop Feedback Control for Production Optimization of Intelligent Wells Under Uncertainty
, SPE PRODUCTION & OPERATIONS, Vol: 28, Pages: 345-357, ISSN: 1930-1855- Author Web Link
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- Citations: 14
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Journal articleLegler B, Johnson HD, Hampson GJ, et al., 2013,
Facies model of a fine-grained, tide-dominated delta: lower Dir Abu Lifa Member (Eocene), Western Desert, Egypt
, Sedimentology, Vol: 60, Pages: 1313-1356Existing facies models of tide-dominated deltas largely omit fine-grained, mud-rich successions. Sedimentary facies and sequence stratigraphic analysis of the exceptionally well-preserved Late Eocene Dir Abu Lifa Member (Western Desert, Egypt) aims to bridge this gap. The succession was deposited in a structurally controlled, shallow, macrotidal embayment and deposition was supplemented by fluvial processes but lacked wave influence. The succession contains two stacked, progradational parasequence sets bounded by regionally extensive flooding surfaces. Within this succession two main genetic elements are identified: non-channelised tidal bars and tidal channels. Non-channelised tidal bars comprise coarsening-upward sand bodies, including large, downcurrent-dipping accretion surfaces, sometimes capped by palaeosols indicating emergence. Tidal channels are preserved as single-storey and multilateral bodies filled by: (i) laterally migrating, elongate tidal bars (inclined heterolithic strata, 5 to 25 m thick); (ii) forward-facing lobate bars (sigmoidal heterolithic strata, up to 10 m thick); (iii) side bars displaying oblique to vertical accretion (4 to 7 m thick); or (iv) vertically-accreting mud (1 to 4 m thick). Palaeocurrent data show that channels were swept by bidirectional tidal currents and typically were mutually evasive. Along-strike variability defines a similar large-scale architecture in both parasequence sets: a deeply scoured channel belt characterised by widespread inclined heterolithic strata is eroded from the parasequence-set top, and flanked by stacked, non-channelised tidal bars and smaller channelised bodies. The tide-dominated delta is characterised by: (i) the regressive stratigraphic context; (ii) net-progradational stratigraphic architecture within the succession; (iii) the absence of upward deepening trends and tidal ravinement surfaces; and (iv) architectural relations that demonstrate contemporaneous tidal distributary channel infill and ti
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Journal articleAgar S, Geiger S, Leonide P, et al., 2013,
Summary of the AAPG–SPE–SEG Hedberg Research Conference on “Fundamental Controls on Flow in Carbonates”
, AAPG Bulletin, Vol: 97, Pages: 533-552A joint AAPG–Society of Petroleum Engineers–Society of Exploration Geophysicists Hedberg Research Conference was held in Saint-Cyr sur Mer, France, on July 8 to 13, 2012, to review current research and explore future research directions related to improved production from carbonate reservoirs. Eighty-seven scientists from academia and industry (split roughly equally) attended for five days. A primary objective for the conference was to explore novel connections among different disciplines (primarily within geoscience and reservoir engineering) as a way to define new research opportunities. Research areas represented included carbonate sedimentology and stratigraphy, structural geology, geomechanics, hydrology, reactive transport modeling, seismic imaging (including four-dimensional seismic, tomography, and seismic forward modeling), geologic modeling and forward modeling of geologic processes, petrophysics, statistical methods, numerical methods for simulation, reservoir engineering, pore-scale processes, in-situ flow experiments (e.g., x-ray computed tomography), visualization, and methods for data interaction.
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Journal articleSolano JMS, Jackson MD, Sparks RSJ, et al., 2012,
Melt Segregation in Deep Crustal Hot Zones: a Mechanism for Chemical Differentiation, Crustal Assimilation and the Formation of Evolved Magmas
, Journal of Petrology, Vol: 53, Pages: 1999-2026, ISSN: 1460-2415Mantle-derived basaltic sills emplaced in the lower crust provide amechanism for the generation of evolved magmas in deep crustal hotzones (DCHZ).This study uses numerical modelling to characterizethe time required for evolved magma formation, the depth and temperatureat which magma formation occurs, and the composition ofthe magma.The lower crust is assumed to comprise amphibolite. Inan extension of previous DCHZ models, the new model couples heattransfer during the repetitive emplacement of sills with mass transfervia buoyancy-driven melt segregation along grain boundaries.The resultsshed light on the dynamics of DCHZ development and evolution.TheDCHZ comprises a mush of crystals plus interstitial melt,except when a new influx of basaltic magma yields a short-lived(20^200 years) reservoir of melt plus suspended crystals (magma).Melt segregation and accumulation within the mush yields two contrastingmodes of evolved magma formation, which operate over timescalesof c. 10 kyr-1 Myr, depending upon emplacement rate andstyle. In one, favoured by emplacement via over-accretion, or emplacementat high rates, evolved magma forms in the crust overlying theintruded basalt sills, and is composed of crustal partial melt, and residualmelt that has migrated upwards out of the crystallizingbasalt. In the other, favoured by emplacement via under- orintra-accretion, or by emplacement at lower rates, evolved magmaforms in the intruded basalt, and the resulting magma is composedprimarily of residual melt. In all cases, the upward migration ofbuoyant melt yields cooler and more evolved magmas, which arebroadly granitic in composition. Chemical differentiation is thereforedriven by melt migration, because the melt migrates through, andchemically equilibrates with, partially molten rock at progressivelylower temperatures. Crustal assimilation occurs during partial melting,and mixing of crustal and residual melt occurs when residualmelt migrates into the partially molten crust, yielding
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Journal articleGlover PWJ, Walker E, Jackson MD, 2012,
Streaming-potential coefficient of reservoir rock: A theoretical model
, Geophysics, Vol: 77, Pages: D17-D43, ISSN: 1942-2156The streaming potential is that electrical potential whichdevelops when an ionic fluid flows through the pores of a rock.It is an old concept that is recently being applied in many fieldsfrom monitoring water fronts in oil reservoirs to understandingthe mechanisms behind synthetic earthquakes. We have carriedout fundamental theoretical modeling of the streaming-potentialcoefficient as a function of pore fluid salinity, pH, and temperatureby modifying the HS equation for use with porous rocksand using input parameters from established fundamental theory(the Debye screening length, the Stern-plane potential, the zetapotential, and the surface conductance). The model also requiresthe density, electrical conductivity, relative electric permittivityand dynamic viscosity of the bulk fluid, for which empiricalmodels are used so that the temperature of the model may bevaried. These parameters are then combined with parametersthat describe the rock microstructure. The resulting theoreticalvalues have been compared with a compilation of data for siliceousmaterials comprising 290 streaming-potential coefficientmeasurements and 269 zeta-potential measurements obtainedexperimentally for 17 matrix-fluid combinations (e.g., sandstonesaturated with KCl), using data from 29 publications.The theoretical model was found to ably describe the main featuresof the data, whether taken together or on a sample by samplebasis. The low-salinity regime was found to be controlled bysurface conduction and rock microstructure, and was sensitiveto changes in porosity, cementation exponent, formation factor,grain size, pore size and pore throat size as well as specific surfaceconductivity. The high-salinity regime was found to be subjectto a zeta-potential offset that allows the streaming-potentialcoefficient to remain significant even as the saturation limit isapproached
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Journal articleJackson MD, Vinogradov J, 2012,
Impact of wettability on laboratory measurements of streaming potential in carbonates
, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Vol: 393, Pages: 86-95, ISSN: 0927-7757- Author Web Link
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- Citations: 64
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Journal articleJackson MD, Leinov E, 2012,
On the Validity of the “Thin” and “Thick”Double-Layer Assumptions When CalculatingStreaming Currents in Porous Media
, International Journal of Geophysics, Vol: 2012, ISSN: 1687-8868We find that the thin double layer assumption, in which the thickness of the electrical diffuse layer is assumed small comparedto the radius of curvature of a pore or throat, is valid in a capillary tubes model so long as the capillary radius is >200 times thedouble layer thickness, while the thick double layer assumption, in which the diffuse layer is assumed to extend across the entirepore or throat, is valid so long as the capillary radius is >6 times smaller than the double layer thickness. At low surface chargedensity (<10 mC · m−2) or high electrolyte concentration (>0.5 M) the validity criteria are less stringent. Our results suggest thatthe thin double layer assumption is valid in sandstones at low specific surface charge (<10 mC · m−2), but may not be valid insandstones of moderate- to small pore-throat size at higher surface charge if the brine concentration is low (<0.001 M). The thickdouble layer assumption is likely to be valid in mudstones at low brine concentration (<0.1 M) and surface charge (<10 mC·m−2),but at higher surface charge, it is likely to be valid only at low brine concentration (<0.003 M). Consequently, neither assumptionmay be valid in mudstones saturated with natural brines.
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Journal articleJackson MD, Gulamali MY, Leinov E, et al., 2012,
Spontaneous Potentials in Hydrocarbon Reservoirs during Waterflooding: Application to Waterfront Monitoring
, SPE Journal -
Journal articleSaunders JH, Jackson MD, Pain CC, et al., 2012,
Streaming potentials in hydrocarbon reservoir conditions
, Geophysics, Vol: 77, Pages: E77-E90 -
Journal articleJackson MD, Butler AP, Vinogradov J, 2012,
Measurements of Spontaneous Potential in Chalk with Application to Aquifer Characterisation in the Southern UK
, Quarterly Journal of Engineering Geology and Hydrogeology -
Journal articleJackson MD, Vinogradov J, Saunders JH, et al., 2011,
Laboratory Measurements and Numerical Modeling of Streaming Potential for Downhole Monitoring in Intelligent Wells
, SPE JOURNAL, Vol: 16, Pages: 625-636, ISSN: 1086-055X- Author Web Link
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- Citations: 7
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Journal articleGulamali MY, Leinov E, Jackson MD, 2011,
Self-potential anomalies induced by water injection into hydrocarbon reservoirs
, GEOPHYSICS, Vol: 76, Pages: F283-F292, ISSN: 0016-8033 -
Journal articleGulamali MY, Leinov E, Jackson MD, 2011,
Self-potential anomalies induced by water injection into hydrocarbon reservoirs
, Geophysics, Vol: 76, Pages: F283-F292, ISSN: 1942-2156The injection of cold water into a hydrocarbon reservoir containingrelatively warmer, more saline formation brine may generateself-potential anomalies as a result of electrokinetic,thermoelectric, and=or electrochemical effects. We havenumerically assessed the relative contributions of these effectsto the overall self-potential signal generated during oil productionin a simple hydrocarbon reservoir model. Our aim was todetermine if measurements of self-potential at a production wellcan be used to detect the movement of water toward the well.The coupling coefficients for the electrochemical and thermoelectricpotentials are uncertain, so we considered four differentmodels for them. We also investigated the effect of altering thesalinities of the formation and injected brines. We found thatthe electrokinetic potential peaked at the location of the saturationfront (reaching values of 0.2 mV even for the most salinebrine considered). Moreover, the value at the production wellincreased as the front approached the well, exceeding the noiselevel ( 0.1 mV). Thermoelectric effects gave rise to largerpotentials in the reservoir (10 mV), but values at the wellwere negligible ð Þ .0:1 mV until after water breakthroughbecause of the lag in the temperature front relative to the saturationfront. Electrochemical potentials were smaller in magnitudethan thermoelectric potentials in the reservoir but were measurableð Þ > 0:1 mV at the well because the salinity front wasclosely associated with the saturation front. When the formationbrine was less saline (1 mol=liter), electrokinetic effects dominated;at higher salinities (5 mol=liter), electrochemicaleffects were significant. We concluded that the measurement ofself-potential signals in a production well may be used to monitorthe movement of water in hydrocarbon reservoirs duringproduction, but further research is required to understand thethermoelectric and electrochemical coupling coefficients in partiallysatu
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