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Sample records for rocks reservoir bitterroot

  1. Evaluation of Management of Water Release for Painted Rocks Reservoir, Bitterroot River, Montana, 1984 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lere, Mark E. (Montana Department of Fish, Wildlife and Parks, Missoula, MT)

    1984-11-01

    Baseline fisheries and habitat data were gathered during 1983 and 1984 to evaluate the effectiveness of supplemental water releases from Painted Rocks Reservoir in improving the fisheries resource in the Bitterroot River. Discharge relationships among main stem gaging stations varied annually and seasonally. Flow relationships in the river were dependent upon rainfall events and the timing and duration of the irrigation season. Daily discharge monitored during the summers of 1983 and 1984 was greater than median values derived at the U.S.G.S. station near Darby. Supplemental water released from Painted Rocks Reservoir totaled 14,476 acre feet in 1983 and 13,958 acre feet in 1984. Approximately 63% of a 5.66 m{sup 3}/sec test release of supplemental water conducted during April, 1984 was lost to irrigation withdrawals and natural phenomena before passing Bell Crossing. A similar loss occurred during a 5.66 m{sup 3}/sec test release conducted in August, 1984. Daily maximum temperature monitored during 1984 in the Bitterroot River averaged 11.0, 12.5, 13.9 and 13.6 C at the Darby, Hamilton, Bell and McClay stations, respectively. Chemical parameters measured in the Bitterroot River were favorable to aquatic life. Population estimates conducted in the Fall, 1983 indicated densities of I+ and older rainbow trout (Salmo gairdneri) were significantly greater in a control section than in a dewatered section (p < 0.20). Numbers of I+ and older brown trout (Salmo trutta) were not significantly different between the control and dewatered sections (p > 0.20). Population and biomass estimates for trout in the control section were 631/km and 154.4 kg/km. In the dewatered section, population and biomass estimates for trout were 253/km and 122.8 kg/km. The growth increments of back-calculated length for rainbow trout averaged 75.6 mm in the control section and 66.9mm in the dewatered section. The growth increments of back-calculated length for brown trout averaged 79.5 mm in the

  2. Evaluation of Management of Water Releases for Painted Rocks Reservoir, Bitterroot River, Montana, 1983-1986, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Spoon, Ronald L. (Montana Department of Fish, Wildlife and Parks, Missoula, MT)

    1987-06-01

    This study was initiated in July, 1983 to develop a water management plan for the release of water purchased from Painted Rocks Reservoir. Releases were designed to provide optimum benefits to the Bitterroot River fishery. Fisheries, habitat, and stream flow information was gathered to evaluate the effectiveness of these supplemental releases in improving trout populations in the Bitterroot River. The study was part of the Northwest Power Planning Council's Fish and Wildlife Program and was funded by the Bonneville Power Administration. This report presents data collected from 1983 through 1986.

  3. Rock-property changes during reservoir compaction

    Energy Technology Data Exchange (ETDEWEB)

    Morita, N. (Conoco, Inc., Ponca City, OK (United States)); Gray, K.E. (Texas Univ., Austin, TX (United States)); Srouji, F.A.A.; Jogi, P.N. (Teleco Oilfield Services Inc., Meviden, CT (US))

    1992-09-01

    Deformations, absolute permeability, electrical resistivity, PV change, and compressional- and shear-wave velocities were measured for Berea sandstone under various loading paths at temperatures from 70 to 380{degrees} F. The experimental behavior was subdivided into five categories. The experimental results were analyzed for each category, and the analysis was used to construct semianalytical rock-property equations, are expressed in terms of strain components. This formalism is practical because strains are more directly related to rock properties that are stress components. This paper presents unique rock-property data, including axial and radial measurements with various loading paths and temperatures; semianalytical equations that accurately simulate rock properties under various loading paths up to rock failure; and realistic predictions of rock-property changes during reservoir compaction.

  4. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  5. Preliminary Rock Physics Characterization of Mississippian Carbonate Reservoir in Canada

    Science.gov (United States)

    Lee, M.; Keehm, Y.; Kim, H.

    2011-12-01

    The Mississippian formations in the Western Canada Sedimentary Basin are known to have large hydrocarbon resources. The Lodgepole formation is the most important reservoir for oil production in Daly and Virden fields. In this study, we performed preliminary reservoir characterization using rock physics modeling. We first delineated the Lodgepole formation by geological information, well-logs and core analysis data. Then, we conducted rock physics analyses such as GR-AI, DEM modeling, porosity-Vp, density-Vp, and porosity-permeability. We identified the Lodgepole formation has different porosity types, volume of shale, and the degree of fractures in difference intervals. In the upper part of the formation, we found that vuggy pores are well developed. Inter-particular porosity and fractures become significant as the depth increases. We found that the lower part can be divided into two groups by acoustic impedance. The prospective reservoir interval, one of the two groups, has higher fracture density, which can be identified by lower acoustic impedance. This result also implies that we could also use AVO analyses to delineate good reservoir intervals. In conclusion, rock physics modeling can be effectively applied to characterize the Lodgepole formation quantitatively with well-log and core analysis data. Acknowledgement: This work was supported by the Energy Resources R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2009201030001A).

  6. Integrated Geophysical Techniques for Exploring Deep Volcanic Rock Reservoir

    Institute of Scientific and Technical Information of China (English)

    LiuXuejun; UDechun; ZhangChangjiang; RanXuefeng

    2003-01-01

    The Carboniferous and Pre-Carboniferous formations in Ludong, Zhungar basin, contain favorable oil/gas reservoirs. The Carboniferous formations, however, are complex in structure and exhibit lateral variations in lithology. Seismic reflections from Pre-Triassic formations are poor and the volcanic reservoirs are very difficult to identify. The analysis of physical properties concluded that the major targets in this region, i.e., the top of the Jurassic and Carboniferous formations, provide distinct density interfaces. The basic, intermediate and acid volcanic rocks were also different in density,resulting in distinguishable gravity anomalies. The differences in magnetism in this region existed not only between the volcanic rocks and clastic sedimentary rocks but also among volcanic rocks with different compositions. All formations and volcanic rocks of different lithologies presented high and low resistance interbeds, which are characterized by regional trends.The modeling study demonstrated that non-seismic integrated geophysical techniques should be feasible in this region, especiaUy the high-precision gravity/magnetic methods combined with long offset transient electromagnetic sounding.

  7. Effect of diagenesis on compaction of reservoir rocks

    OpenAIRE

    Olgaard, D.; Cameron, S.; Dunsmuir, J.; Herhold, A.; King, H; Gooch, M. J.

    2007-01-01

    Predicting sediment porosity-depth trends and ultimately the quality of reservoir rocks requires an understanding of mechanical and chemical compaction mechanisms during diagenesis. In many siliciclastic sediments porosity versus depth profiles can be predicted from the sediment’s stress history. In carbonates such predictions are more difficult because chemical diagenesis is prevalent even within a few meters of the seafloor. We used a systematic laboratory approach to investigate th...

  8. Identification of clay minerals in reservoir rocks by FTIR spectroscopy

    Science.gov (United States)

    Cong Khang, Vu; Korovkin, Mikhail V.; Ananyeva, Ludmila G.

    2016-09-01

    Clay minerals including kaolinite, montmorillonite and bentonite in oil and gas reservoir rocks are identified by absorption spectra obtained via Fourier Transform Infrared (FTIR) spectroscopy. Bands around 3695, 3666, 3650 and 3630 cm-1 and bands around 3620 and 3400 cm-1 are the most diagnostically reliable for kaolinite and montmorillonite, respectively; also absorption bands in the region of 1200...955 cm-1 are equally diagnostic for all the clay minerals studied.

  9. Grain-rimming kaolinite in Permian Rotliegend reservoir rocks

    Science.gov (United States)

    Waldmann, Svenja; Gaupp, Reinhard

    2016-04-01

    Upper Rotliegend sediments of Permian age from the northeast Netherlands show moderate to good reservoir qualities. The predominant control is by the presence of authigenic grain-rimming kaolinite, which has a negative, but in some parts also a positive, effect on reservoir quality. To better understand the formation and distribution of grain-rimming kaolinite, reservoir rocks were studied in terms of composition and diagenetic processes. Petrographic evidence, summarized as a paragenetic sequence, is integrated with geochemical modeling results to identify early mesodiagenetic water-rock interactions under the participation of gases, i.e., CO2 and H2S, released from underlying Carboniferous source rocks. The sediments investigated were deposited at varying distance from the southern flank of the Southern Permian Basin. Sediments near the basin margin are mainly attributed to a fluvial environment and comprise medium to coarse-grained sandstones and conglomerates. There, vermicular kaolinite occurs with a lath-like structure. Distal to the basin margin, mainly in sandstones intercalated with fine-grained playa sediments, comparatively high amounts of grain-rimming kaolinite occur. There, the presence of this mineral has a significant influence on the rock properties and the reservoir quality. Geochemical modeling suggests that the formation of such kaolinites cannot be explained exclusively by in situ feldspar dissolution. The modeling results support evidence that kaolinite can be formed from precursor clay minerals under the presence of CO2-rich formation waters. Such clay minerals could be corrensite, smectite-chlorite mixed-layer minerals, or chlorite that is potentially present in Rotliegend sediments during early diagenesis. Furthermore, the geochemical modeling can reflect several mineral reactions that were identified from petrographic analysis such as the formation of illite and kaolinite at the expense of feldspar dissolution and consequent silica

  10. Case Study of Volcanic Rock Reservoir--Beibao Area of Nanbao Sag

    Institute of Scientific and Technical Information of China (English)

    Guo Qijun; Wan Zhimin; Jiao Shouquan; Liu Laixiang

    1997-01-01

    @@ Preface Crude has been produced from volcanic rock reservoirs inAmerica, Libya, Indonesia and Japan, according to the available data. Oil and gas Production from volcanic rock reservoirs in Japan accounts for 30% of the total, with the recoverable reserves estimated at 48% of the total. Oil and gas traps of volcanic rock reservoir with better reservoir properties and flow potential have been discovered in Liaohe, Erlian, Jizhong, Huanghua, Jiyang, Linqing,Jiangsu and Xinjiang of China since the 1970's. However,the systematic study of volcanic rock reservoir is just in the beginning.

  11. SEISMIC AND ROCK PHYSICS DIAGNOSTICS OF MULTISCALE RESERVOIR TEXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2003-10-01

    As part of our study on ''Relationships between seismic properties and rock microstructure'', we have (1) Studied relationships between velocity and permeability. (2) Used independent experimental methods to measure the elastic moduli of clay minerals as functions of pressure and saturation. (3) Applied different statistical methods for characterizing heterogeneity and textures from scanning acoustic microscope (SAM) images of shale microstructures. (4) Analyzed the directional dependence of velocity and attenuation in different reservoir rocks (5) Compared Vp measured under hydrostatic and non-hydrostatic stress conditions in sands. (6) Studied stratification as a source of intrinsic anisotropy in sediments using Vp and statistical methods for characterizing textures in sands.

  12. Characterization of CO2 reservoir rock in Switzerland

    Science.gov (United States)

    Fabbri, Stefano; Madonna, Claudio; Zappone, Alba

    2014-05-01

    Anthropogenic emissions of Carbon Dioxide (CO2) are one of the key drivers regarding global climate change (IPCC, 2007). Carbon Dioxide Capture and Storage (CCS) is one valuable technology to mitigate current climate change with an immediate impact. The IPCC special report on CCS predicted a potential capture range of 4.7 to 37.5 Gt of CO2 by 2050. Among several countries, Switzerland has started to investigate its potential for CO2 storage (Chevalier et al., 2010) and is currently performing research on the characterization of the most promising reservoir/seal rocks for CO2 sequestration. For Switzerland, the most feasible option is to store CO2 in saline aquifers, sealed by impermeable formations. One aquifer of regional scale in the Swiss Molasse Basin is a carbonate sequence consisting of reworked shallow marine limestones and accumulations of shell fragments. The upper part of the formation presents the most promising permeability values and storage properties. The storage potential has been estimated of 706 Mt of CO2, based on the specific ranking scheme proposed by Chevalier et al. 2010. In this study, key parameters such as porosity, permeability and acoustic velocities in compressional and shear mode have been measured in laboratory at pressures and temperatures simulating in situ conditions. Reservoir rock samples have been investigated. Permeability has been estimated before and after CO2 injection in supercritical state. The simulation of typical reservoir conditions allows us to go one step further towards a significant evaluation of the reservoir's true capacities for CO2 sequestration. It seems of major importance to notice that the permeability crucially depends on confining pressure, temperature and pore pressure conditions of the sample. Especially at in situ conditions with CO2 being at supercritical state, a substantial loss in permeability have to be taken into consideration when it comes to the calculation of potential injection rates. The

  13. Development of a segmentation method for analysis of Campos basin typical reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Rego, Eneida Arendt; Bueno, Andre Duarte [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Macae, RJ (Brazil). Lab. de Engenharia e Exploracao de Petroleo (LENEP)]. E-mails: eneida@lenep.uenf.br; bueno@lenep.uenf.br

    2008-07-01

    This paper represents a master thesis proposal in Exploration and Reservoir Engineering that have the objective to development a specific segmentation method for digital images of reservoir rocks, which produce better results than the global methods available in the bibliography for the determination of rocks physical properties as porosity and permeability. (author)

  14. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Science.gov (United States)

    Ma, Xiangxian; Zheng, Guodong; Xu, Wang; Liang, Minliang; Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin; Shozugawa, Katsumi; Matsuo, Motoyuki

    2016-12-01

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  15. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiangxian; Zheng, Guodong, E-mail: gdzhbj@mail.iggcas.ac.cn; Xu, Wang [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Liang, Minliang [Chinese Academy of Geological Sciences, Institute of Geomechanics, Key Lab of Shale Oil and Gas Geological Survey (China); Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Shozugawa, Katsumi; Matsuo, Motoyuki [The University of Tokyo, Graduate School of Arts and Sciences (Japan)

    2016-12-15

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  16. Geologic Features of Wangjiatun Deep Gas Reservoirs of Volcanic Rock in Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    SHAN Xuanlong; CHEN Shumin; WU Dawei; Zang Yudong

    2001-01-01

    Wangjiatun gas pool is located at the north part of Xujiaweizi in Songliao basin. Commercial gas flow has been found in the intermediate and acid volcanic rock of upper Jurassic - lower Cretaceous, which makes a breakthrough in deep nature gas prospecting in Songliao basin. The deep natural gas entrapment regularity is discussed in the paper by the study of deep strata, structure and reservoir. Andesite, rhyolite and little pyroclastic rock are the main reservoirs. There are two types of volcanic reservoir space assemblage in this area: the pore and fissure and the pure fissure. Changes had taken place for volcanic reservoir space during long geologic time, which was controlled by tectonic movement and geologic environment.The developed degree of reservoir space was controlled by tectonic movement, weathering and filtering, corrosion and Filling. There are three types of source- reservoir-caprock assemblage in this area: lower source- upper reservoir model,upper source - lower reservoir model and lateral change model. Mudstone in Dengluoku formation and the compacted volcanic rock of upper Jurassic - lower Cretaceous are the caprock for deep gas reservoirs. Dark mudstone of deep lacustrine facies in Shahezi formation and lower part of Dengluoku formation are the source rock of deep gas. It can be concluded that deep gas pools are mainly volcanic lithologic reservoirs.

  17. Hydro-mechanically coupled modelling of deep-seated rock slides in the surroundings of reservoirs

    Science.gov (United States)

    Lechner, Heidrun; Preh, Alexander; Zangerl, Christian

    2016-04-01

    In order to enhance the understanding of the behaviour of deep-seated rock slides in the surroundings of large dam reservoirs, this study concentrates on failure mechanisms, deformation processes and the ability of self-stabilisation of rock slides influenced by reservoirs. Particular focus is put on internal rock mass deformations, progressive topographical slope changes due to reservoir impoundment and shear displacements along the basal shear zone in relation to its shear strength properties. In this study, a two-dimensional numerical rock slide model is designed by means of the Universal Distinct Element Code UDEC and investigated concerning different groundwater flow scenarios. These include: (i) a completely drained rock slide model, (ii) a model with fully saturated rock mass below an inclined groundwater table and (iii) a saturated groundwater model with a reservoir at the slope toe. Slope displacements initiate when the shear strength properties of the basal shear zone are at or below the critical parameters for the limit-equilibrium state and continue until a numerical equilibrium is reached due to deformation- and displacement-based geometrical changes. The study focuses on the influence of a reservoir at the toe of a rock slide and tries to evaluate the degree of displacement which is needed for a re-stabilisation in relation to the geometrical characteristics of the rock slide. Besides, challenges and limitations of applied distinct element methods to simulate large strain and displacements of deep-seated rock slides are discussed. The ongoing study will help to understand the deformation behaviour of deep-seated pre-existing rock slides in fractured rock mass during initial impounding and will be part of a hazard assessment for large reservoirs.

  18. Fracturing tests on reservoir rocks: Analysis of AE events and radial strain evolution

    CERN Document Server

    Pradhan, S; Fjær, E; Stenebråten, J; Lund, H K; Sønstebø, E F; Roy, S

    2015-01-01

    Fracturing in reservoir rocks is an important issue for the petroleum industry - as productivity can be enhanced by a controlled fracturing operation. Fracturing also has a big impact on CO2 storage, geothermal installation and gas production at and from the reservoir rocks. Therefore, understanding the fracturing behavior of different types of reservoir rocks is a basic need for planning field operations towards these activities. In our study, the fracturing of rock sample is monitored by Acoustic Emission (AE) and post-experiment Computer Tomography (CT) scans. The fracturing experiments have been performed on hollow cylinder cores of different rocks - sandstones and chalks. Our analysis show that the amplitudes and energies of acoustic events clearly indicate initiation and propagation of the main fractures. The amplitudes of AE events follow an exponential distribution while the energies follow a power law distribution. Time-evolution of the radial strain measured in the fracturing-test will later be comp...

  19. Laboratory monitoring of CO2 migration within brine-saturated reservoir rock though complex electrical impedance

    NARCIS (Netherlands)

    Kirichek, O.; Ghose, R.; Heller, H.K.J.

    2013-01-01

    We investigate the ability of complex electrical measurements to monitor the CO2 front propagation within brine-saturated reservoir rock. A laboratory facility has been developed to perform CO2-brine substitution experiments under reservoir conditions. In the present study, CO2 is injected into a br

  20. A method for determining the reservoir properties of water saturated rock

    Energy Technology Data Exchange (ETDEWEB)

    Khaibullin, A.S.; Belobskaia, P.V.; Demidovich, L.A.; Gurskii, G.V.

    1980-05-15

    This invention relates to petrographic methods for studying rock. The goal of this invention is to make it possible to determine the entire array of the reservoir properties possessed by the rock under study using a single sample. This is achieved by an arrangement where the sample under study is heated up with non-isothermic conditions in the heater. Then the ranges that are characterized by a constant change in the moisture loss velocity and that correspond to the isolation of 3-bound and strongly bound moisture are then reported. The reservoir properties of the rock are determined by the volume of moisture that is isolated during these intervals. The sequence of operations for the proposed method used in determining the reservoir properties of the rock is examined.

  1. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    NARCIS (Netherlands)

    Marketos, G.; Spiers, C.J.; Govers, R.

    2016-01-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically

  2. Use of ``rock-typing`` to characterize carbonate reservoir heterogeneity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ikwuakor, K.C.

    1994-03-01

    The objective of the project was to apply techniques of ``rock-typing`` and quantitative formation evaluation to borehole measurements in order to identify reservoir and non-reservoir rock-types and their properties within the ``C`` zone of the Ordovician Red River carbonates in the northeast Montana and northwest North Dakota areas of the Williston Basin. Rock-typing discriminates rock units according to their pore-size distribution. Formation evaluation estimates porosities and pore fluid saturation. Rock-types were discriminated using crossplots involving three rock-typing criteria: (1) linear relationship between bulk density and porosity, (2) linear relationship between acoustic interval transit-time and porosity, and (3) linear relationship between acoustic interval transit-time and bulk density. Each rock-type was quantitatively characterized by the slopes and intercepts established for different crossplots involving the above variables, as well as porosities and fluid saturations associated with the rock-types. All the existing production was confirmed through quantitative formation evaluation. Highly porous dolomites and anhydritic dolomites contribute most of the production, and constitute the best reservoir rock-types. The results of this study can be applied in field development and in-fill drilling. Potential targets would be areas of porosity pinchouts and those areas where highly porous zones are downdip from non-porous and tight dolomites. Such areas are abundant. In order to model reservoirs for enhanced oil recovery (EOR) operations, a more localized (e.g. field scale) study, expanded to involve other rock-typing criteria, is necessary.

  3. Seismic monitoring of heavy oil reservoirs: Rock physics and finite element modelling

    Science.gov (United States)

    Theune, Ulrich

    In the past decades, remote monitoring of subsurface processes has attracted increasing attention in geophysics. With repeated geophysical surveys one attempts to detect changes in the physical properties in the underground without directly accessing the earth. This technique has been proven to be very valuable for monitoring enhanced oil recovery programs. This thesis presents an modelling approach for the feasibility analysis for monitoring of a thermal enhanced oil recovery technique applied to heavy oil reservoirs in the Western Canadian Sedimentary Basin. In order to produce heavy oil from shallow reservoirs thermal oil recovery techniques such as the Steam Assisted Gravity Drainage (SAGD) are often employed. As these techniques are expensive and technically challenging, early detection of operational problems is without doubt of great value. However, the feasibility of geophysical monitoring depends on many factors such as the changes in the rock physical properties of the target reservoir. In order to access the feasibility of seismic monitoring for heavy oil reservoirs, a fluid-substitutional rock physical study has been carried out to simulate the steam injection. The second modelling approach is based on a modified finite element algorithm to simulate the propagation of elastic waves in the earth, which has been developed independently in the framework of this thesis. The work summarized in this thesis shows a possibility to access the feasibility of seismic monitoring for heavy oil reservoirs through an extensive rock-physical study. Seismic monitoring is a useful tool in reservoir management decision process. However, the work reported here suggests that seismic monitoring of SAGD processes in the heavy oil reservoirs of the Western Canadian Sedimentary Basin is only feasible in shallow, unconsolidated deposits. For deeper, but otherwise geological similar reservoirs, the SAGD does not create a sufficient change in the rock physical properties to be

  4. Social science and the Bitterroot National Forest: A synthesis

    Science.gov (United States)

    Stephen F. McCool; James Burchfield; Wayne Freimund

    2000-01-01

    The objective of this research was to synthesize a number of studies focusing on human dimensions of public land management in the Bitterroot National Forest. While 35-40 such studies have been conducted, their cumulative knowledge is limited by use of a variety of approaches, scales and frameworks. Four themes emerged from the synthesis: public attitudes toward...

  5. Upscaling of permeability heterogeneities in reservoir rocks; an integrated approach

    NARCIS (Netherlands)

    Mikes, D.

    2002-01-01

    This thesis presents a hierarchical and geologically constrained deterministic approach to incorporate small-scale heterogeneities into reservoir flow simulators. We use a hierarchical structure to encompass all scales from laminae to an entire depositional system. For the geological models under c

  6. Exploration Potential of Marine Source Rocks Oil-Gas Reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    So far, more than 150 marine oil-gas fields have been found onshore and offshore about 350.The marine source rocks are mainly Paleozoic and Mesozoic onshore whereas Tertiary offshore. Three genetic categories of oil-gas reservoirs have been defined for the marine reservoirs in China: primary reservoirs, secondary reservoirs and hydrocarbon-regeneration reservoirs. And three exploration prospects have also been suggested: (1) Primary reservoirs prospects, which are chiefly distributed in many Tertiary basins of the South China Sea (SCS), the Tertiary shelf basins of the East China Sea (ECS) and the Paleozoic of Tarim basin, Sichuan basin and Ordos basin. To explore large-middle-scale even giant oil-gas fields should chiefly be considered in this category reservoirs. These basins are the most hopeful areas to explore marine oil-gas fields in China, among which especially many Tertiary basins of the SCS should be strengthened to explore. (2) Secondary reservoirs prospects, which are mainly distributed in the Paleozoic and Mesozoic of the Tarim basin, Sichuan basin, Qiangtang basin and Chuxiong basin in western China, of which exploration potential is less than that of the primary reservoirs. (3) Hydrocarbon-regeneration reservoirs prospects, which are chiefly distributed in the Bohai Bay basin, North Jiangsu-South Yellow Sea basin, southern North China basin, Jianghan basin,South Poyang basin in eastern China and the Tarim basin in western China, of which source rocks are generally the Paleozoic. And the reservoirs formed by late-stage (always Cenozoic) secondary hydrocarbon generation of the Paleozoic source rocks should mainly be considered to explore, among which middle-small and small oil-gas fields are the chief exploration targets. As a result of higher thermal evolution of Paleozoic and Mesozoic source rocks, the marine reservoirs onshore are mainly gas fields, and so far marine oil fields have only been found in the Tarim basin. No other than establishing

  7. A Percolation Study of Wettability Effect on the Electrical Properties of Reservoir Rocks

    DEFF Research Database (Denmark)

    Zhou, Dengen; Arbabi, Sepehr; Stenby, Erling Halfdan

    1997-01-01

    Measurements of the electrical resistivity of oil reservoirs are commonly used to estimate other properties of reservoirs, such as porosity and hydrocarbon reserves. However, the interpretation of the measurements is based on empirical correlations, because the underlying mechanisms that control...... the electrical properties of oil bearing rocks have not been well understood. In this paper, we employ percolation concepts to investigate the effect of wettability on the electrical conductivity of a reservoir formation. A three-dimensional simple cubic network is used to represent an ideal reservoir formation...... behavior of reservoir resistivities of different wettabilities. It demonstrates that the resistivity index depends on saturation history and wettability. For strongly oil-wet systems, significant hysteresis is expected, while there is little hysteresis for strongly water-wet systems, and some hysteresis...

  8. Anisotropic rock physics models for interpreting pore structures in carbonate reservoirs

    Institute of Scientific and Technical Information of China (English)

    Li Sheng-Jie; Shao Yu; Chen Xu-Qiang

    2016-01-01

    We developed an anisotropic effective theoretical model for modeling the elastic behavior of anisotropic carbonate reservoirs by combining the anisotropic self-consistent approximation and differential effective medium models. By analyzing the measured data from carbonate samples in the TL area, a carbonate pore-structure model for estimating the elastic parameters of carbonate rocks is proposed, which is a prerequisite in the analysis of carbonate reservoirs. A workfl ow for determining elastic properties of carbonate reservoirs is established in terms of the anisotropic effective theoretical model and the pore-structure model. We performed numerical experiments and compared the theoretical prediction and measured data. The result of the comparison suggests that the proposed anisotropic effective theoretical model can account for the relation between velocity and porosity in carbonate reservoirs. The model forms the basis for developing new tools for predicting and evaluating the properties of carbonate reservoirs.%♦Corresponding author: Li Sheng-Jie (Email: Richard@cup.edu.cn)

  9. Pressure-velocity relations in reservoir rocks: Modified MacBeth's equation

    Science.gov (United States)

    Grana, Dario

    2016-09-01

    The knowledge of the saturation and pressure effects on elastic properties is a key factor in reservoir monitoring. The relation between saturation changes and velocity variations is well known in rock physics and at seismic frequency it can be satisfactorily described by Gassmann's equations. The pressure effect still requires deeper investigations in order to be included in rock physics models for 4D studies. Theoretical models of velocity-pressure relations often do not match lab measurements, or contain empirical constants or theoretical parameters that are difficult to calibrate or do not have a precise physical meaning. In this work, I present a new model to describe the pressure sensitivity of elastic moduli for clastic rocks. The proposed model is an extension of MacBeth's relations. These equations are then integrated within a complete rock physics model to describe the relation between rock properties (porosity and clay content), dynamic attributes (saturation and pressure) and elastic properties. The proposed model is calibrated with laboratory measurements of dry samples over a wide range of pressure variations and then applied to well data to simulate different production scenarios. The complete rock physics model can then be used in time-lapse inversion to predict the distribution of dynamic property changes in the reservoir within an inversion workflow for reservoir monitoring.

  10. Rock-physics and seismic-inversion based reservoir characterization of the Haynesville Shale

    Science.gov (United States)

    Jiang, Meijuan; Spikes, Kyle T.

    2016-06-01

    Seismic reservoir characterization of unconventional gas shales is challenging due to their heterogeneity and anisotropy. Rock properties of unconventional gas shales such as porosity, pore-shape distribution, and composition are important for interpreting seismic data amplitude variations in order to locate optimal drilling locations. The presented seismic reservoir characterization procedure applied a grid-search algorithm to estimate the composition, pore-shape distribution, and porosity at the seismic scale from the seismically inverted impedances and a rock-physics model, using the Haynesville Shale as a case study. All the proposed rock properties affected the seismic velocities, and the combined effects of these rock properties on the seismic amplitude were investigated simultaneously. The P- and S-impedances correlated negatively with porosity, and the V P/V S correlated positively with clay fraction and negatively with the pore-shape distribution and quartz fraction. The reliability of these estimated rock properties at the seismic scale was verified through comparisons between two sets of elastic properties: one coming from inverted impedances, which were obtained from simultaneous inversion of prestack seismic data, and one derived from these estimated rock properties. The differences between the two sets of elastic properties were less than a few percent, verifying the feasibility of the presented seismic reservoir characterization.

  11. SEISMIC AND ROCK PHYSICS DIAGNOSTICS OF MULTISCALE RESERVOIR TEXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2003-06-01

    As part of our study on ''Relationships between seismic properties and rock microstructure'', we have studied (1) Elastic properties of clay minerals using Pulse Transmission experiments. We show measurements of elastic moduli and strain in clay minerals.

  12. Comparison and analysis of reservoir rocks and related clays

    Energy Technology Data Exchange (ETDEWEB)

    Crocker, M.E.; Donaldson, E.C.; Marchin, L.M.

    1983-10-01

    A series of instrumental and chemical analyses was made on sedimentary rocks to determine the surface chemical properties of sedimentry rocks and the physical characteristic of the pores. A scanning electron microscope (SEM) with energy dispersive X-ray analytic capability was used to study the morphology of the samples, surface mineral composition and type and location of clays, and to obtain a qualitative estimate of the pore sizes. A centrifuge was used to determine the pore size distributions which are correlated with SEM observations. An atomic absorption spectrophotometer equipped with an inductively coupled plasma for complete spectral analysis was used to obtain analyses of the rocks, clays, and effluents from ion exchange tests. Two of the results are as follows: (1) Sweetwater gas sands have a bimodal pore size distribution composed of pores with a mean diameter of 0.2 microns which is attributed to intergranular spaces and cracks in the expanded laborboratory sample but which will be close under the pressure of the overburden formations, and these Sweetwater sands have a distribution of pores at 2 microns which are solution vugs rather than intergranular porosity since the sand grains are completely packed together with the cementing material due to the high overburden pressures; and (2) Ion-exchange capacities of two rocks were 5.3 meq/kg and 18.0 meq/kg, and the surface areas were 0.9 m/sup 2//g and 2.30 m/sup 2//g, respectively, even though each had almost identical mineral composition, clay type and quantity, and permeability. 7 references, 12 figures, 3 tables.

  13. Numerical simulation of the electrical properties of shale gas reservoir rock based on digital core

    Science.gov (United States)

    Nie, Xin; Zou, Changchun; Li, Zhenhua; Meng, Xiaohong; Qi, Xinghua

    2016-08-01

    In this paper we study the electrical properties of shale gas reservoir rock by applying the finite element method to digital cores which are built based on an advanced Markov Chain Monte Carlo method and a combination workflow. Study shows that the shale gas reservoir rock has strong anisotropic electrical conductivity because the conductivity is significantly different in both horizontal and vertical directions. The Archie formula is not suitable for application in shale reservoirs. The formation resistivity decreases in two cases; namely (a) with the increase of clay mineral content and the cation exchange capacity of clay, and (b) with the increase of pyrite content. The formation resistivity is not sensitive to the solid organic matter but to the clay and gas in the pores.

  14. Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering’s failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

  15. Brittleness index and seismic rock physics model for anisotropic tight-oil sandstone reservoirs

    Institute of Scientific and Technical Information of China (English)

    Huang Xin-Rui; Huang Jian-Ping; Li Zhen-Chun; Yang Qin-Yong; Sun Qi-Xing; Cui Wei

    2015-01-01

    Brittleness analysis becomes important when looking for sweet spots in tight-oil sandstone reservoirs. Hence, appropriate indices are required as accurate brittleness evaluation criteria. We construct a seismic rock physics model for tight-oil sandstone reservoirs with vertical fractures. Because of the complexities in lithology and pore structure and the anisotropic characteristics of tight-oil sandstone reservoirs, the proposed model is based on the solid components, pore connectivity, pore type, and fractures to better describe the sandstone reservoir microstructure. Using the model, we analyze the brittleness sensitivity of the elastic parameters in an anisotropic medium and establish a new brittleness index. We show the applicability of the proposed brittleness index for tight-oil sandstone reservoirs by considering the brittleness sensitivity, the rock physics response characteristics, and cross-plots. Compared with conventional brittleness indexes, the new brittleness index has high brittleness sensitivity and it is the highest in oil-bearing brittle zones with relatively high porosity. The results also suggest that the new brittleness index is much more sensitive to elastic properties variations, and thus can presumably better predict the brittleness characteristics of sweet spots in tight-oil sandstone reservoirs.

  16. Probe imaging studies of magnetic susceptibility and permeability for sensitive characterisation of carbonate reservoir rocks

    Science.gov (United States)

    Ivakhnenko, Aleksandr; Bigaliyeva, Akmaral; Dubinin, Vladislav

    2016-04-01

    In this study were disclosed the main principals of identifying petrophysical properties of carbonate reservoirs such as porosity, permeability and magnetic susceptibility. While exploring and developing reservoir there are significant diversity of tasks that can be solved by appropriate knowledge of properties which are listed above. Behavior of fluid flow, distribution of hydrocarbons and other various industrial applications can be solved by measuring areal distribution of these petrophysical parameters. The results demonstrate how magnetic probe and hysteresis measurements correlate with petrophysical parameters in carbonate reservoirs. We made experimental measurements and theoretical calculations of how much magnetic susceptibility depends on the porosity of the rocks and analyzed data with graphics. In theoretical model of the carbonate rocks we considered calcite, dolomite, quartz and combinations of calcite and dolomite, calcite and Fe-dolomite, calcite and quartz, calcite and aragonite with increasing concentrations of the dolomite, Fe-dolomite, quartz and aragonite up to 50% with step of 5%. Here we defined dependence of magnetic susceptibility from the porosity: the higher porosity measurements, the less slope of magnetic susceptibility, consequently mass magnetization is higher for diamagnetic and lower for paramagnetic carbonate rocks, but in the both cases magnetic susceptibility tries to reach zero with increasing of the total porosity. Rock measurements demonstrate that reservoir zones of the low diamagnetic magnetic susceptibility are generally correlated with higher permeability and also porosity distribution. However for different carbonate reservoirs we establish different relationships depending on the complexity of their mineralogy and texture. Application of integral understanding in distribution of permeability, porosity and mineral content in heterogeneous carbonates represented by this approach can be useful tool for carbonate reservoir

  17. EVALUATION OF RESERVOIR ROCK AND WELL BORE CEMENT ALTERATION WITH SUPERCRITICAL CO2

    Energy Technology Data Exchange (ETDEWEB)

    William k. O' Connor; Gilbert E Rush

    2009-01-01

    An evaluation of the alteration of reservoir rock and well bore cement at their interface, under supercritical CO{sub 2} (SCCO{sub 2}), was conducted at the laboratory-scale using simulated brine solutions at down-hole conditions. These studies were intended to identify potential leakage pathways for injected CO{sub 2} due to degradation of the well bore. Two distinct test series were conducted on core samples of the Mt. Simon sandstone from the Illinois Basin, IL, and the Grand Ronde basalt from the Pasco Basin, WA. LaFarge Class H well bore cement was used for both series. Reservoir rock/cement cores were immersed within a CO{sub 2}-saturated brine for up to 2000 hours at 35 degrees C and 100 atm CO{sub 2}. Results suggest that the impact of SCCO{sub 2} injection is reservoir-specific, being highly dependent on the reservoir brine and rock type. Brine pH can be significantly altered by CO{sub 2} injection, which in turn can dramatically impact the dissolution characteristics of the reservoir rock. Finally, well bore cement alteration was identified, particularly for fresh cast cement allowed to cure at SCCO{sub 2} conditions. However, this alteration was generally limited to an outer rind of carbonate and Ca-depleted cement which appeared to protect the majority of the cement core from further attack. These studies indicate that at the cement-rock interface, the annular space may be filled by carbonate which could act as an effective barrier against further CO{sub 2} migration along the well bore.

  18. Quantifying porosity and permeability of fractured carbonates and fault rocks in natural groundwater reservoirs

    Science.gov (United States)

    Pirmoradi, Reza; Wolfmayr, Mariella; Bauer, Helene; Decker, Kurt

    2017-04-01

    This study presents porosity and permeability data for a suite of different carbonate rocks from two major groundwater reservoirs in eastern Austria that supply more than 60% of Vienna`s drinking water. Data includes a set of lithologically different, unfractured host rocks, fractured rocks with variable fracture intensities, and fault rocks such as dilation breccias, different cataclasites and dissolution-precipitation fault rocks. Fault rock properties are of particular importance, since fault zones play an important role in the hydrogeology of the reservoirs. The reservoir rocks are exposed at two major alpine karst plateaus in the Northern Calcareous Alps. They comprise of various Triassic calcareous strata of more than 2 km total thickness that reflect facies differentiation since Anisian times. Rocks are multiply deformed resulting in a partly dense network of fractures and faults. Faults differ in scale, fault rock content, and fault rock volumes. Methods used to quantify the porosity and permeability of samples include a standard industry procedure that uses the weight of water saturated samples under hydrostatic uplift and in air to determine the total effective (matrix and fracture) porosity of rocks, measurements on plugs with a fully automated gas porosity- and permeameter using N2 gas infiltrating plugs under a defined confining pressure (Coreval Poro 700 by Vinci technologies), and percolation tests. The latter were conducted in the field along well known fault zones in order to test the differences in fractured rock permeability in situ and on a representative volume, which is not ensured with plug measurements. To calculate hydraulic conductivity by the Darcy equation the measured elapsed time for infiltrating a standard volume of water into a small borehole has been used. In general, undisturbed host rock samples are all of low porosity (average around 1%). The open porosity of the undisturbed rocks belonging to diverse formations vary from 0

  19. SEISMIC AND ROCK PHYSICS DIAGNOSTICS OF MULTISCALE RESERVOIR TEXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2002-05-01

    As part of our study on ''Relationships between seismic properties and rock microstructure'', we have studied (1) How to quantify elastic properties of clay minerals using Atomic Force Acoustic Microscopy. We show how bulk modulus of clay can be measured using atomic force acoustic microscopy (AFAM) (2) We have successfully measured elastic properties of unconsolidated sediments in an effort to quantify attributes for detection of overpressures from seismic (3) We have initiated efforts for velocity upscaling to quantify long-wavelength and short-wavelength velocity behavior and the scale-dependent dispersion caused by sediment variability in different depositional environments.

  20. Rock Physics of Reservoir Rocks with Varying Pore Water Saturation and Pore Water Salinity

    DEFF Research Database (Denmark)

    Katika, Konstantina

    be performed on specific geological structures and why it is sometimes successful; has yet to be established. The presence of both oil and water in the pore space, several different ions present in the injected water that contact the pore walls, possible changes in the fluid wetting the surface of the grains......Advanced waterflooding (injection of water with selective ions in reservoirs) is a method of enhanced oil recovery (EOR) that has attracted the interest of oil and gas companies that exploit the Danish oil and gas reservoirs. This method has been applied successfully in oil reservoirs...... and in the Smart Water project performed in a laboratory scale in order to evaluate the EOR processes in selected core plugs. A major step towards this evaluation is to identify the composition of the injected water that leads to increased oil recovery in reservoirs and to define changes in the petrophysical...

  1. Velocity dispersion: A tool for characterizing reservoir rocks

    Science.gov (United States)

    Brown, R.L.; Seifert, D.

    1997-01-01

    Apparent discrepancies between velocity measurements made with different frequencies in a formation at the Gypsy test site are explained in terms of elastic scattering and intrinsic attenuation. The elastic scattering component of the dispersion (38%) in a marine interval above the Gypsy sandstone is estimated via simple models constructed from well log information. Any dispersion above the predicted value for elastic scattering in this interval is assigned to intrinsic attenuation (62%). Using the vertical measurements in the well, the marine interval directly above the Gypsy sandstone has an estimated intrinsic Q1 = 51 and an effective Q because of the scattering of Qsc = 85. The total Q of the combined mechanisms is 32. The dispersion of the vertical measurements through the heterogeneous sands and shales of the Gypsy formation can be explained using an intrinsic QI = 30 and neglecting the effects of scattering. The horizontal observations require a more detailed modeling effort to unravel the relative roles of path and volume effects, elastic scattering, attenuation, and intrinsic anisotropy. Thin layers barely resolvable on the sonic logs play a significant role in modifying the crosswell response. Potentially, the dispersion can be a key to mapping reservoir properties using crosswell and surface seismic data.

  2. A rock physics model for analysis of anisotropic parameters in a shale reservoir in Southwest China

    Science.gov (United States)

    Qian, Keran; Zhang, Feng; Chen, Shuangquan; Li, Xiangyang; Zhang, Hui

    2016-02-01

    A rock physics model is a very effective tool to describe the anisotropy and mechanical properties of rock from a seismology perspective. Compared to a conventional reservoir, modelling a shale reservoir requires us to face two main challenges in modelling: the existence of organic matter and strong anisotropy. We construct an anisotropic rock physics workflow for a typical shale reservoir in Southwest China, in which the organic matter is treated separately from other minerals by using a combination of anisotropic self-consistent approximation and the differential effective medium method. The standard deviation of the distribution function is used to model the degree of lamination of clay and kerogen. A double scan workflow is introduced to invert the probability of pore aspect ratio and lamination simultaneously, which can give us a better understanding of the shale formation. The anisotropic properties of target formation have been analysed based on the proposed model. Inverted Thomsen parameters, especially the sign of delta, are analysed in terms of the physical properties of rock physics modelling.

  3. MULTI-ATTRIBUTE SEISMIC/ROCK PHYSICS APPROACH TO CHARACTERIZING FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2000-10-01

    This project consists of three key interrelated Phases, each focusing on the central issue of imaging and quantifying fractured reservoirs, through improved integration of the principles of rock physics, geology, and seismic wave propagation. This report summarizes the results of Phase I of the project. The key to successful development of low permeability reservoirs lies in reliably characterizing fractures. Fractures play a crucial role in controlling almost all of the fluid transport in tight reservoirs. Current seismic methods to characterize fractures depend on various anisotropic wave propagation signatures that can arise from aligned fractures. We are pursuing an integrated study that relates to high-resolution seismic images of natural fractures to the rock parameters that control the storage and mobility of fluids. Our goal is to go beyond the current state-of-the art to develop and demonstrate next generation methodologies for detecting and quantitatively characterizing fracture zones using seismic measurements. Our study incorporates 3 key elements: (1) Theoretical rock physics studies of the anisotropic viscoelastic signatures of fractured rocks, including up scaling analysis and rock-fluid interactions to define the factors relating fractures in the lab and in the field. (2) Modeling of optimal seismic attributes, including offset and azimuth dependence of travel time, amplitude, impedance and spectral signatures of anisotropic fractured rocks. We will quantify the information content of combinations of seismic attributes, and the impact of multi-attribute analyses in reducing uncertainty in fracture interpretations. (3) Integration and interpretation of seismic, well log, and laboratory data, incorporating field geologic fracture characterization and the theoretical results of items 1 and 2 above. The focal point for this project is the demonstration of these methodologies in the Marathon Oil Company Yates Field in West Texas.

  4. Porosity, permeability and 3D fracture network characterisation of dolomite reservoir rock samples.

    Science.gov (United States)

    Voorn, Maarten; Exner, Ulrike; Barnhoorn, Auke; Baud, Patrick; Reuschlé, Thierry

    2015-03-01

    With fractured rocks making up an important part of hydrocarbon reservoirs worldwide, detailed analysis of fractures and fracture networks is essential. However, common analyses on drill core and plug samples taken from such reservoirs (including hand specimen analysis, thin section analysis and laboratory porosity and permeability determination) however suffer from various problems, such as having a limited resolution, providing only 2D and no internal structure information, being destructive on the samples and/or not being representative for full fracture networks. In this paper, we therefore explore the use of an additional method - non-destructive 3D X-ray micro-Computed Tomography (μCT) - to obtain more information on such fractured samples. Seven plug-sized samples were selected from narrowly fractured rocks of the Hauptdolomit formation, taken from wellbores in the Vienna basin, Austria. These samples span a range of different fault rocks in a fault zone interpretation, from damage zone to fault core. We process the 3D μCT data in this study by a Hessian-based fracture filtering routine and can successfully extract porosity, fracture aperture, fracture density and fracture orientations - in bulk as well as locally. Additionally, thin sections made from selected plug samples provide 2D information with a much higher detail than the μCT data. Finally, gas- and water permeability measurements under confining pressure provide an important link (at least in order of magnitude) towards more realistic reservoir conditions. This study shows that 3D μCT can be applied efficiently on plug-sized samples of naturally fractured rocks, and that although there are limitations, several important parameters can be extracted. μCT can therefore be a useful addition to studies on such reservoir rocks, and provide valuable input for modelling and simulations. Also permeability experiments under confining pressure provide important additional insights. Combining these and

  5. Rock physics modeling of heterogeneous carbonate reservoirs:porosity estimation and hydrocarbon detection

    Institute of Scientific and Technical Information of China (English)

    Yu Hao; Ba Jing; Carcione Jose; Li Jin-Song; Tang Gang; Zhang Xing-Yang; He Xin-Zhen; Ouyang Hua

    2014-01-01

    In heterogeneous natural gas reservoirs, gas is generally present as small patch-like pockets embedded in the water-saturated host matrix. This type of heterogeneity, also called“patchy saturation”, causes significant seismic velocity dispersion and attenuation. To establish the relation between seismic response and type of fluids, we designed a rock physics model for carbonates. First, we performed CT scanning and analysis of the fluid distribution in the partially saturated rocks. Then, we predicted the quantitative relation between the wave response at different frequency ranges and the basic lithological properties and pore fluids. A rock physics template was constructed based on thin section analysis of pore structures and seismic inversion. This approach was applied to the limestone gas reservoirs of the right bank block of the Amu Darya River. Based on poststack wave impedance and prestack elastic parameter inversions, the seismic data were used to estimate rock porosity and gas saturation. The model results were in good agreement with the production regime of the wells.

  6. Formation of source and reservoir rocks in a sequence stratigraphic framework Jameson Land East Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Piasecki, S.; Dam, G.; Hansen, C.F.; Koppelhus, E.B.; Stemmerik, L.; Surlyk, F.

    1996-12-31

    Sedimentological, biostratigraphical and sequence stratigraphical analyses of East Greenland sedimentary successions with significant source and reservoir qualities have resulted in a major increase in the understanding of their depositional conditions, distribution and geometry`s. A biostratigraphical scheme of the Jurassic succession based on spores, pollen and dinoflaggelate cyst has been constructed for correlation and dating of the very detailed sequence stratigraphical units across the North Atlantic Ocean. Middle and Upper Jurassic dinoflaggelate stratigraphy is closely correlated to Boreal ammonite stratigraphy and deviations from the NW-European standard dinocyst stratigraphy have been recorded. The Upper Permian Folvik Creek Group was deposited in a marine, carbonate-dominated depositional system under arid climatic conditions. The organic-rich shales of the Ravnefjeld Formation represents highstand systems tracts. Reservoir rocks were formed by secondary dissolution of carbonates which were exposed during low relativ sea-level and as sandy turbidites deposited in lowstand systems tract. The uppermost Triassic - lowermost Jurassic Kap Stewart Group was deposited in a large rift lake. Organic-rich shales were deposited distally during lake level highstand. Deltaic reservoir sandstones were deposited in lowstand systems tracts as a respond to forced regressin induced by rapid variations in relative lake-level. The overlying marine Jurassic deposits include several sandstone units with reservoir potential representing both lowstand and high stand systems tracts. The organic rich mudstones were only developed as potential source rocks for oil when the deposition was combined with high marine organic production and basinal anoxic conditions e.g. during deposition of the Middle Jurassic Sortehat Formation and the Upper Jurassic Hareelv Formations. Several of the largestloilfields in the North Sea and on the Norwegian shelf have close analogues in the Jurassic

  7. Formation of source and reservoir rocks in a sequence stratigraphic framework Jameson Land East Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Piasecki, S.; Dam, G.; Hansen, C.F.; Koppelhus, E.B.; Stemmerik, L.; Surlyk, F.

    1996-12-31

    Sedimentological, biostratigraphical and sequence stratigraphical analyses of East Greenland sedimentary successions with significant source and reservoir qualities have resulted in a major increase in the understanding of their depositional conditions, distribution and geometry`s. A biostratigraphical scheme of the Jurassic succession based on spores, pollen and dinoflaggelate cyst has been constructed for correlation and dating of the very detailed sequence stratigraphical units across the North Atlantic Ocean. Middle and Upper Jurassic dinoflaggelate stratigraphy is closely correlated to Boreal ammonite stratigraphy and deviations from the NW-European standard dinocyst stratigraphy have been recorded. The Upper Permian Folvik Creek Group was deposited in a marine, carbonate-dominated depositional system under arid climatic conditions. The organic-rich shales of the Ravnefjeld Formation represents highstand systems tracts. Reservoir rocks were formed by secondary dissolution of carbonates which were exposed during low relativ sea-level and as sandy turbidites deposited in lowstand systems tract. The uppermost Triassic - lowermost Jurassic Kap Stewart Group was deposited in a large rift lake. Organic-rich shales were deposited distally during lake level highstand. Deltaic reservoir sandstones were deposited in lowstand systems tracts as a respond to forced regressin induced by rapid variations in relative lake-level. The overlying marine Jurassic deposits include several sandstone units with reservoir potential representing both lowstand and high stand systems tracts. The organic rich mudstones were only developed as potential source rocks for oil when the deposition was combined with high marine organic production and basinal anoxic conditions e.g. during deposition of the Middle Jurassic Sortehat Formation and the Upper Jurassic Hareelv Formations. Several of the largest oilfields in the North Sea and on the Norwegian shelf have close analogues in the Jurassic

  8. Climate modeling - a tool for the assessment of the paleodistribution of source and reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Roscher, M.; Schneider, J.W. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Geologie; Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany). Referat Organische Geochemie/Kohlenwasserstoff-Forschung

    2008-10-23

    In an on-going project of BGR and TU Bergakademie Freiberg, numeric paleo-climate modeling is used as a tool for the assessment of the paleo-distribution of organic rich deposits as well as of reservoir rocks. This modeling approach is based on new ideas concerning the formation of the Pangea supercontinent. The new plate tectonic concept is supported by paleo- magnetic data as it fits the 95% confidence interval of published data. Six Permocarboniferous time slices (340, 320, 300, 290, 270, 255 Ma) were chosen within a first paleo-climate modeling approach as they represent the most important changes of the Late Paleozoic climate development. The digital maps have a resolution of 2.8 x 2.8 (T42), suitable for high-resolution climate modeling, using the PLASIM model. CO{sub 2} concentrations of the paleo-atmosphere and paleo-insolation values have been estimated by published methods. For the purpose of validation, quantitative model output, had to be transformed into qualitative parameters in order to be able to compare digital data with qualitative data of geologic indicators. The model output of surface temperatures and precipitation was therefore converted into climate zones. The reconstructed occurrences of geological indicators like aeolian sands, evaporites, reefs, coals, oil source rocks, tillites, phosphorites and cherts were then compared to the computed paleo-climate zones. Examples of the Permian Pangea show a very good agreement between model results and geological indicators. From the modeling approach we are able to identify climatic processes which lead to the deposition of hydrocarbon source and reservoir rocks. The regional assessment of such atmospheric processes may be used for the identification of the paleo-distribution of organic rich deposits or rock types suitable to form hydrocarbon reservoirs. (orig.)

  9. Sulfidogenesis and Control in Fractured Rock: Laboratory Experiments and Implication for Souring Intervention in Oil Reservoirs

    Science.gov (United States)

    Wu, Y.; Hubbard, C. G.; Geller, J. T.; Ajo Franklin, J. B.

    2016-12-01

    Microbial sulfidogenesis in oil reservoirs, referred to as souring, is commonly encountered during sea water flooding. A better understanding of the souring process and effective control is of great interest to the oil industry. While a large fraction of global oil reserve is found in fractured rock, understanding of sulfidogenesis and control in fractured rock is next to non-existent. Complex and contrasting flow properties between fracture and matrix result in heterogeneous thermal and reaction gradients, posing great challenges to both experimental and modeling studies. We conducted the first experiment on biogenic sulfidogenesis and control in fractured rock. A 2D flow cell was used and straight fractures were created in order to reduce complexity, producing datasets more amenable to models. Heating was applied to simulate temperature gradients from colder sea-water injection. Perchlorate treatment was performed following sulfidogenesis as a thermodynamic control strategy. Synthetic sea water (SSW) with acetate was used as the growth media. Inoculations were carried out with sulfate reducing and perchlorate reducing microbes. A set of control and monitoring methods was applied including temperature, optical and infrared imaging, distributed galvanic sensing and fluid sampling as well as influent/effluent monitoring. Tracer tests were conducted before and after the experiment. Our experiment captured the dynamics of sulfur cycling in fractured rocks. Time-lapse optical imaging recorded the evolution of microbial biomass. Infrared imaging revealed the thermal gradient and the impacts from flow. Such data was essential for the identification of a mesophilic zone and it's co-location with sufidogenesis. Galvanic-potential signals provided the critical dataset for tracking spatial sulfide distribution over time. Our experiment demonstrated for the first time the role of heterogeneous flow and temperature controlling sulfidogenesis and treatment in fractured rock

  10. Petrophysical Clasification of Different Rocks in Carbonate Reservoirs of the Northern Cuban Heavy Oil Belt

    Directory of Open Access Journals (Sweden)

    Odalys Reyes Paredes

    2014-09-01

    Full Text Available The permeability is one of the main parameters to classify the porosity environment, this parametercan't be measured by log's tools, and it has no direct relation with the total porosity. It is closely relatedto the kind of rock (size and distribution of particles. In the Northern Cuban Heavy Oil Belt (FNCPC,the reservoirs are made up of carbonate rocks (mudstone / wackestone, with fracture porosity andother types of porosity such as: joins of dissolution and estilolitos formed from diagenetic processes.The different formations frequently show heterogeneities that can be noticeable hindering their owncharacterization. The cores present a very poor recuperation and on numerous occasions recoveringonly intervals that don't contribute anything to the flow of fluids. The analysis about different kinds ofrocks is done in this article; it is conceived throughout data of cores and thin sections. The petrophysicalclassification of different kinds of rocks for carbonate reservoirs are established from the porosity andpermeability relationships and porosity environment structure.

  11. Diagenesis of the Silurian oil reservoir rock from the Kudirka Atoll in Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Stentoft, N.; Lapinskas, P.; Musteikis, P.; Kristensen, L.

    2001-07-01

    The Upper Solurian limestone rocks of the Kudirka Atoll reef-complex show a complex diagnetic history. By thin section petrography on 50 samples from 7 wells the following sequence of diagenetic events (from oldest to youngest) could be established with a rather high degree of certainty: Compaction/dewatering {yields} Early lithification {yields} Insignificant fracturing {yields} ?First generation of leaching {yields} Precipitation of first generation of inter-/intra-granular calcite cement {yields} Precipitation of second generation of inter-/intra-granular calcite cement {yields} Recrystallization of lime mud, sparry calcite cements, and fossils {yields} Chemical compaction with formation of stylolite-associated fractures {yields} Precipitation of dolomite, pyrite and silica crystals {yields} Second generation of leaching with stylolite surfaces acting as conduits for aggressive fluids {yields} Oil emplacement. In all types of reef rock the late diagenetic leaching phase has favourably influenced the present reservoir quality ({kappa} and {phi}). No clear correlation was found between rock texture and reservoir quality. The numerous crinoid fragments in samples of biosparite/biosparrudite and poorly washed biosparite/biosparudite are primarily responsible for that, as the rate of growth of syntaxial rimcement on the single-crystalline echinoderm fragments was far greater than the rate og growth of cement on associated multi-crystalline fossils. However, the calcite-replacing calcitic dolomite-crystals, that are associated with the stylolitic joints, have also inplaces contributed to the lacking correlation (au)

  12. Wettability from Capillarity of CO2-Brine-Rock Systems at Reservoir Conditions

    Science.gov (United States)

    Al-Menhali, Ali; Niu, Ben; Krevor, Samuel

    2015-04-01

    The wettability of CO2-brine-rock systems will have a major impact on the management of carbon sequestration in subsurface geological formations. Recent contact angle measurement studies have reported sensitivity in wetting behaviour of this system to pressure, temperature and brine salinity. We report results of an investigation into the impact of reservoir conditions on wetting through direct observations of their impact on the capillary strength of the system. Eight capillary pressure characteristic curves were measured using CO2 and brine in a single fired Berea sandstone at pressures (5 to 20 MPa), temperatures (25 to 50 °C) and ionic strengths (0 to 5 M kg-1 NaCl) representative of subsurface reservoirs. A ninth measurement using an N2-water system provided a benchmark for capillarity with a strongly water wet system. The semi-dynamic capillary pressure core flooding technique was used with in situ saturation monitoring. In all cases, the capillarity of the system, scaled by the interfacial tension, were equivalent to the N2-water system within measurement uncertainty. Thus reservoir conditions did not have a significant impact on the capillary strength of the CO2-brine system through a variation in wetting. Two steady-state relative permeability measurements with CO2 and brine and one with N2 and brine similarly show little variation between conditions, consistent with the observation that the CO2-brine-sandstone system is strongly water wetting and invariant across a wide range of reservoir conditions.

  13. Eastern rock sengis as reservoir hosts of Anaplasma bovis in South Africa.

    Science.gov (United States)

    Harrison, Alan; Bastos, Armanda D S; Medger, Katarina; Bennett, Nigel C

    2013-12-01

    Recent work has identified the presence of Anaplasma bovis, a tick-borne pathogen of cattle, in a previously undescribed species of tick collected from eastern rock sengis, Elephantulus myurus, in Limpopo Province, South Africa. These small insectivores are endemic to Africa and are important hosts of immature ticks, however, their role as reservoirs of tick-borne pathogens has not been investigated. In order to elucidate the role of sengis in the epidemiology of A. bovis, we screened the blood of 105 sengis from Limpopo Province, South Africa, for the presence of members of the genera Anaplasma and Ehrlichia by PCR. A total of 30/105 (28.6%) of individuals were infected with A. bovis, and nucleotide sequencing revealed the presence of a novel genetic variant of this pathogen. This represents the first evidence that sengis may be natural reservoir hosts of A. bovis. Copyright © 2013 Elsevier GmbH. All rights reserved.

  14. Integrating sequence stratigraphy and rock-physics to interpret seismic amplitudes and predict reservoir quality

    Science.gov (United States)

    Dutta, Tanima

    This dissertation focuses on the link between seismic amplitudes and reservoir properties. Prediction of reservoir properties, such as sorting, sand/shale ratio, and cement-volume from seismic amplitudes improves by integrating knowledge from multiple disciplines. The key contribution of this dissertation is to improve the prediction of reservoir properties by integrating sequence stratigraphy and rock physics. Sequence stratigraphy has been successfully used for qualitative interpretation of seismic amplitudes to predict reservoir properties. Rock physics modeling allows quantitative interpretation of seismic amplitudes. However, often there is uncertainty about selecting geologically appropriate rock physics model and its input parameters, away from the wells. In the present dissertation, we exploit the predictive power of sequence stratigraphy to extract the spatial trends of sedimentological parameters that control seismic amplitudes. These spatial trends of sedimentological parameters can serve as valuable constraints in rock physics modeling, especially away from the wells. Consequently, rock physics modeling, integrated with the trends from sequence stratigraphy, become useful for interpreting observed seismic amplitudes away from the wells in terms of underlying sedimentological parameters. We illustrate this methodology using a comprehensive dataset from channelized turbidite systems, deposited in minibasin settings in the offshore Equatorial Guinea, West Africa. First, we present a practical recipe for using closed-form expressions of effective medium models to predict seismic velocities in unconsolidated sandstones. We use an effective medium model that combines perfectly rough and smooth grains (the extended Walton model), and use that model to derive coordination number, porosity, and pressure relations for P and S wave velocities from experimental data. Our recipe provides reasonable fits to other experimental and borehole data, and specifically

  15. Diffusion and spatially resolved NMR in Berea and Venezuelan oil reservoir rocks.

    Science.gov (United States)

    Murgich, J; Corti, M; Pavesi, L; Voltini, F

    1992-01-01

    Conventional and spatially resolved proton NMR and relaxation measurements are used in order to study the molecular motions and the equilibrium and nonequilibrium diffusion of oils in Berea sandstone and Venezuelan reservoir rocks. In the water-saturated Berea a single line with T*2 congruent to 150 microseconds is observed, while the relaxation recovery is multiexponential. In an oil reservoir rock (Ful 13) a single narrow line is present while a distribution of relaxation rates is evidenced from the recovery plots. On the contrary, in the Ful 7 sample (extracted at a deeper depth in a different zone) two NMR components are present, with 3.5 and 30 KHz linewidths, and the recovery plot exhibits biexponential law. No echo signal could be reconstructed in the oil reservoir rocks. These findings can be related to the effects in the micropores, where motions at very low frequency can occur in a thin layer. From a comparison of the diffusion constant in water-saturated Berea, D congruent to 5*10(-6) cm2/sec, with the ones in model systems, the average size of the pores is estimated around 40 A. The density profiles at the equilibrium show uniform distribution of oils or of water, and the relaxation rates appear independent from the selected slice. The nonequilibrium diffusion was studied as a function of time in a Berea cylinder with z axis along H0, starting from a thin layer of oil at the base, and detecting the spin density profiles d(z,t) with slice-selection techniques. Simultaneously, the values of T1's were measured locally, and the distribution of the relaxation rates was observed to be present in any slice.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Dilational and Compactional Shear Failure: Application to Siliciclastic Petroleum Reservoir rocks.

    Science.gov (United States)

    Casey, M.; Fisher, Q. J.; Knipe, R. J.

    2001-12-01

    Investigations related to the exploitation of oil reserves provide examples of brittle shear failure in rocks with well known burial, stress, temperature, compactional and diagenetic history. In addition, particular emphasis is placed on the dilational or compactional nature of the failure mode because of the influence this has on the permeability of the fault rocks. Microstructural investigations show that at shallow depths of less than 2.5 km failure during continued subsidence is by particulate flow and is usually compactional. At greater depths mechanical compaction may occur by particulate flow/ grain crushing or the rock may fail by dilational brittle failure. The main control on failure mode is the degree of cementation. At low cementation the rock fails by particulate flow (with or without fracture). Dilational shear failure occurs when the cementation has considerably reduced the porosity. We developed a model of cementation rate based on temperature controlled precipitation rate and used this to plot product of porosity and grain radius (a measure of susceptibility of the rock to crushing) against effective stress for some North Sea Reservoir rocks during their burial history. We found that the initially the low cementation rate held the crushing strength constant, causing the rocks to approach the empirical failure curve, but that at greater depths the increased cementation rate rapidly increased the strength, taking the rock mechanical state away from the failure line. Some deeply buried rocks were observed to have lower than expected amounts of cement and we ascribe this to the inhibition of precipitation by clay films. Deep, well cemented rocks, that failed by shear localised dilatant brittle shear were found to have higher permeabilities than expected on the basis of laboratory results. The natural specimens came from dilational jogs in a network of fault segments and we infer that the increased permeability is the result of deformation under

  17. Fluid identification in tight sandstone reservoirs based on a new rock physics model

    Science.gov (United States)

    Sun, Jianmeng; Wei, Xiaohan; Chen, Xuelian

    2016-08-01

    To identify pore fluids, we establish a new rock physics model named the tight sandstone dual-porosity model based on the Voigt-Reuss-Hill model, approximation for the Xu-White model and Gassmann’s equation to predict elastic wave velocities. The modeling test shows that predicted sonic velocities derived from this rock physics model match well with measured ones from logging data. In this context, elastic moduli can be derived from the model. By numerical study and characteristic analyzation of different elastic properties, a qualitative fluid identification method based on Poisson’s ratio and the S-L dual-factor method based on synthetic moduli is proposed. Case studies of these two new methods show the applicability in distinguishing among different fluids and different layers in tight sandstone reservoirs.

  18. Molecular correlation of free oil and inclusion oil of reservoir rocks in the Junggar Basin, China

    Energy Technology Data Exchange (ETDEWEB)

    Changchun Pan; Jiamo Fu; Guoying Sheng [Chinese Academy of Sciences, Guangdong (China). State Key Laboratory of Organic Geochemistry; Jianqiang Yang [Research Institute of Exploration and Development, Xinjiang (China)

    2003-03-01

    Free oils and inclusion oils (oil-bearing fluid inclusions) of 12 samples collected from the sandstone reservoir formations in the central, eastern and northern areas of the Junggar Basin, northwest China, were analyzed by GC and GC-MS. Analytical results indicate very similar biomarker distributions within each of the free oils and their associated inclusion oils in the two samples collected, respectively, from the northwestern and eastern border of the Junggar Basin. The free oil and inclusion oil of sample MD1-1, collected from the northwestern border, correlate well with the Permian source rock of the Fencheng Formation, while those of sample DN1-1 from the eastern border correlate with the Permian source rock of the Pingdiquan Formation. In contrast, in the central area, the free and inclusion oils vary significantly in most cases, which suggests variations of sources for oil charges during the filling process. These data, and the correlation between the free and inclusion oils, are consistent with the field and seismic data, which show that in areas where samples MD1-1 and DN1-1 are located, only one available source rock exists, while in the central area, multiple source rocks are present. (author)

  19. Petrology of upper silurian reservoir rocks from the Kudirka Atoll, Lithuania. On the spatiotemporal relations between different diagenetic events that have affected the reservoir quality of the rocks

    Energy Technology Data Exchange (ETDEWEB)

    Stentoft, N.; Lapinskas, P.; Musteikis, P.; Kristensen, L.; Hoelstad, T.

    1998-08-01

    The purpose of the study was to provide an understanding of the diagnetic development of the different reservoir rocks of the Kudirka Atoll, and to make out to what degree the present reservoir qualities (permeability and porosity) of the reef rocks are dependent on the preceding post depositional diagenetic events. Beside that the scope was to get a better understanding of the architecture of the reef complex by combining macroscopic core descriptions with log interpretations of selected wells. The spatial distribution of both porosity, water saturation, lithology and texture is included. The project encompasses investigation of core and plug material from following wells of the Kudirka Atoll field: Vilkaviskis-126, -131, -132, -135, -136, -137 and -139. From 50 small core pieces (cf. Appendix A) a total of 100 one inch plug samples were drilled (that is two plus from each core piece) and cleaned by use of soxhlet extractor. Porosity, air permeability and grain density were then measured on each plug (cf. Appendix E). Wireline logs from the seven wells, plus from Vilkaviskis-133 and Kudirka-146, were digitized and used in the log interpretation. To ensure that characteristics essential to both the log interpretation and the diagenetic history were called attention to, the macroscopic core descriptions were carried out in accordance to the procedure described in the `introductory remarks` of Appendix A. The microscopic investigations, that form the basis of the description of the diagenetic history, are based on 50 thin-section (30 {mu}m thick) prepared from one inch plugs (cf Appenix B). To see whether the carbonate crystals, that were assumed to be dolomite from their reaction with Alizarin Red S, are in fact pure, or close to pure CaMg(CO-3){sub 2}, two thin sections were polished and examined by SEM-ED (cf. Appendix F). A total of 15 plugs were picked out for capillary pressure measurements (the porous plate method using 8 pressure steps) including

  20. Petrology of upper silurian reservoir rocks from the Kudirka Atoll, Lithuania. On the spatiotemporal relations between different diagenetic events that have affected the reservoir quality of the rocks

    Energy Technology Data Exchange (ETDEWEB)

    Stentoft, N.; Lapinskas, P.; Musteikis, P.; Kristensen, L.; Hoelstad, T.

    1998-08-01

    The purpose of the study was to provide an understanding of the diagenetic development of the different reservoir rocks of the Kudirka Atoll, and to make out to what degree the present reservoir qualities (permeability and porosity) of the reef rocks are dependent on the preceding post depositional diagenetic events. Beside that the scope was to get a better understanding of the architecture of the reef complex by combining macroscopic core descriptions with log interpretations of selected wells. The spatial distribution of both porosity, water saturation, lithology and texture is included. The project encompasses investigation of core and plug material from following wells of the Kudirka Atoll field: Vilkaviskis-126, -131, -132, -135, -136, -137 and -139. From 50 small core pieces (cf. Appendix A) a total of 100 one inch plug sampels were drilled (that is two plus from each core piece) and cleaned by use of soxhlet extractor. Porosity, air permeability and grain density were then measured on each plug (cf. Appendix E). Wireline logs from the seven wells, plus from Vilkaviskis-133 and Kudirka-146, were digitized and used in the log interpretation. To ensure that characteristics essential to both the log interpretation and the diagnetic history were called attention to, the macroscopic core descriptions were carried out in accordance to the procedure described in the `introductory remarks` of Appendix A. The microscopic investigations, that form the basis of the description of the diagenetic history, are based on 50 thin-section (30 {mu}m thick) prepared from one inch plugs (cf Appenix B). To see whether the carbonate crystals, that were assumed to be dolomite from their reaction with Alizarin Red S, are in fact pure, or close to pure CaMg(CO-3){sub 2}, two thin sections were polished and examined by SEM-ED (cf. Appencix F). A total of 15 plugs were picked out for capillary pressure measurements (the porous plate method using 8 pressure steps) including

  1. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    Science.gov (United States)

    Marketos, G.; Spiers, C. J.; Govers, R.

    2016-06-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically on the role of creep of rock salt caprocks in response to production-induced differential stresses. We start by discussing available rock salt creep flow laws. We then present the subsidence evolution above an axisymmetric finite element representation of a generic reservoir that extends over a few kilometers and explore the effects of rock salt flow law choice on the subsidence response. We find that if rock salt creep is linear, as appropriate for steady state flow by pressure solution, the subsidence response to any pressure reduction history contains two distinct components, one that leads to the subsidence bowl becoming narrower and deeper and one that leads to subsidence rebound and becomes dominant at later stages. This subsidence rebound becomes inhibited if rock salt deforms purely through steady state power law creep at low stresses. We also show that an approximate representation of transient creep leads to relatively small differences in subsidence predictions. Most importantly, the results confirm that rock salt flow must be modeled accurately if good subsidence predictions are required. However, in practice, large uncertainties exist in the creep behavior of rock salt, especially at low stresses. These are a consequence of the spatial variability of rock salt physical properties, which is practically impossible to constrain. A conclusion therefore is that modelers can only resort to calculating bounds for the subsidence evolution above producing rock salt-capped reservoirs.

  2. Evaluation of the second hot dry rock geothermal energy reservoir: results of Phase I, Run Segment 5

    Energy Technology Data Exchange (ETDEWEB)

    Zyvoloski, G.A.; Aamodt, R.L.; Aguilar, R.G.

    1981-09-01

    The results of a long-term (286 day) flow test of the second hot dry rock reservoir at the Fenton Hill field site are presented. This second reservoir was created by fracturing an interval of granitic rock located at a depth of 2.93 km (9620 ft) in the same wellbore pair used in the creation of the first, smaller reservoir. The new fracture system has a vertical extent of at least 320 m (1050 ft), suggesting that the combined heat-transfer area of the old and new fracture systems is much greater than that of the old system. The virgin rock temperature at the bottom of the deeper interval was 197/sup 0/C (386/sup 0/F). Downhole measurements of the water temperature at the reservoir outlet, as well as temperatures inferred from geothermometry, showed that the thermal drawdown of the reservoir was about 8/sup 0/C, and preliminary estimates indicate that the minimum effective heat-transfer area of the new reservoir is 45,000 m/sup 2/ (480,000 ft/sup 2/), which is six times larger than the first reservoir.

  3. Modeling Fluid Flow and Electrical Resistivity in Fractured Geothermal Reservoir Rocks

    Energy Technology Data Exchange (ETDEWEB)

    Detwiler, R L; Roberts, J J; Ralph, W; Bonner, B P

    2003-01-14

    Phase change of pore fluid (boiling/condensing) in rock cores under conditions representative of geothermal reservoirs results in alterations of the electrical resistivity of the samples. In fractured samples, phase change can result in resistivity changes that are more than an order of magnitude greater than those measured in intact samples. These results suggest that electrical resistivity monitoring may provide a useful tool for monitoring the movement of water and steam within fractured geothermal reservoirs. We measured the electrical resistivity of cores of welded tuff containing fractures of various geometries to investigate the resistivity contrast caused by active boiling and to determine the effects of variable fracture dimensions and surface area on water extraction. We then used the Nonisothermal Unsaturated Flow and Transport model (NUFT) (Nitao, 1998) to simulate the propagation of boiling fronts through the samples. The simulated saturation profiles combined with previously reported measurements of resistivity-saturation curves allow us to estimate the evolution of the sample resistivity as the boiling front propagates into the rock matrix. These simulations provide qualitative agreement with experimental measurements suggesting that our modeling approach may be used to estimate resistivity changes induced by boiling in more complex systems.

  4. Measurements of electrical impedance and elastic wave velocity of reservoir rock under fluid-flow test

    Science.gov (United States)

    Sawayama, Kazuki; Kitamura, Keigo; Fujimitsu, Yasuhiro

    2017-04-01

    The estimation of water saturation under the ground is essential in geothermal fields, particularly for EGS (enhanced geothermal system). To estimate water saturation, recently, electromagnetic exploration using Magnetotelluric (MT) method has been applied in the geothermal fields. However, the relationship between electrical impedance obtained from this method and water saturation in the reservoir rock has not been well known. Our goal is to elucidate this basic relationship by fluid-flow experiments. As our first step to this goal, we developed the technique to measure and analyze the electrical impedance of the cracked rock in the geothermal reservoir. The fluid-flow test has been conducted as following procedures. At first, reservoir rock sample (pyroxene andesite, Makizono lava formation, Japan) was filled with nitrogen gas (Pp = 10 MPa) under 20 MPa of confining pressure. This nitrogen gas imitates the overheated steam in the geothermal fields. Then, brine (1wt.%-KCl, 1.75 S/m) which imitates the artificial recharge to the reservoir was injected to the samples. After flow rate of drainage fluid becomes stable, injection pressure was increased (11, 12, 14, 16, 18 MPa) and decreased (18, 16, 14, 12, 11 MPa) to vary the water saturation in the samples. During the test, water saturation, permeability, electrical impedance (10-2-105 Hz of frequency) and elastic wave velocity were measured. As a result of andesite, electrical impedance dramatically decreased from 105 to 103 Ω and P-wave velocity increased by 2% due to the brine injection. This remarkable change of the electrical impedance could be due to the replacement of pre-filled nitrogen gas to the brine. After the brine injection, electrical impedance decreased with injection pressure (small change of water saturation) by up to 40% while P-wave velocity was almost constant (less than 1%). This decrease of electrical impedance with injection pressure could be related to the flow to the narrow path (microcrack

  5. Methane-rich fluid inclusions and their hosting volcanic reservoir rocks of the Songliao Basin, NE China

    Institute of Scientific and Technical Information of China (English)

    WANG Pu-Jun; HOU Qi-jun; CHENG Ri-hui; LI Quan-lin; GUO Zhen-hua; HUANG Yu-long

    2004-01-01

    Methane-rich fluids were recognized to be hosted in the reservoir volcanic rocks as primary inclusions.Samples were collected from core-drillings of volcanic gas reservoirs with reversed δ12C of alkane in the Xujiaweizi depression of the Songliao Basin. The volcanic rocks are rhyolite dominant being enriched in the more incompatible elements like Cs, Rb, Ba, Th, U and Th with relative high LREE, depleted HREE and negative anomalies of Ti and Nb,suggesting a melt involving both in mantle source and crustal assimilation. Primary fluids hosted in the volcanic rocks should have the same provenance with the magma. The authors concluded that the enclosed CH4 in the volcanics are mantle/magma-derived alkane and the reversed δ13C of alkane in the corresponding gas reservoirs is partly resulted from mixture between biogenic and abiogenic gases.

  6. Research on anisotropy of shale oil reservoir based on rock physics model

    Science.gov (United States)

    Guo, Zhi-Qi; Liu, Cai; Liu, Xi-Wu; Dong, Ning; Liu, Yu-Wei

    2016-06-01

    Rock physics modeling is implemented for shales in the Luojia area of the Zhanhua topographic depression. In the rock physics model, the clay lamination parameter is introduced into the Backus averaging theory for the description of anisotropy related to the preferred alignment of clay particles, and the Chapman multi-scale fracture theory is used to calculate anisotropy relating to the fracture system. In accordance with geological features of shales in the study area, horizontal fractures are regarded as the dominant factor in the prediction of fracture density and anisotropy parameters for the inversion scheme. Results indicate that the horizontal fracture density obtained has good agreement with horizontal permeability measured from cores, and thus confirms the applicability of the proposed rock physics model and inversion method. Fracture density can thus be regarded as an indicator of reservoir permeability. In addition, the anisotropy parameter of the P-wave is higher than that of the S-wave due to the presence of horizontal fractures. Fracture density has an obvious positive correlation with P-wave anisotropy, and the clay content shows a positive correlation with S-wave anisotropy, which fully shows that fracture density has a negative correlation with clay and quartz contents and a positive relation with carbonate contents.

  7. Actualistic and Geochemical Modeling of Reservoir Rock, CO2 and Formation Fluid Interaction, Citronelle Oil Field, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Weislogel, Amy [West Virginia Univ., Morgantown, WV (United States)

    2014-01-31

    This report includes description of the Citronelle field study area and the work carried out in the project to characterize the geology and composition of reservoir rock material and to collect an analyze the geochemical composition of produced fluid waters from the Citronelle field. Reservoir rock samples collected from well bore core were made into thin-sections and assessed for textural properties, including pore types and porosity distribution. Compositional framework grain modal data were collected via point-counting, and grain and cement mineralogy was assessed using SEM-EDS. Geochemistry of fluid samples is described and modeled using PHREEQC. Composition of rock and produced fluids were used as inputs for TOUGHREACT reactive transport modeling, which determined the rock-fluid system was in disequilibrium.

  8. Actualistic and Geochemical Modeling of Reservoir Rock, CO2 and Formation Fluid Interaction, Citronelle Oil Field, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Weislogel, Amy

    2014-01-31

    This report includes description of the Citronelle field study area and the work carried out in the project to characterize the geology and composition of reservoir rock material and to collect an analyze the geochemical composition of produced fluid waters from the Citronelle field. Reservoir rock samples collected from well bore core were made into thin-sections and assessed for textural properties, including pore types and porosity distribution. Compositional framework grain modal data were collected via point-counting, and grain and cement mineralogy was assessed using SEM-EDS. Geochemistry of fluid samples is described and modeled using PHREEQC. Composition of rock and produced fluids were used as inputs for TOUGHREACT reactive transport modeling, which determined the rock-fluid system was in disequilibrium.

  9. Sedimentological correlation of heterogeneous reservoir rocks: effects of lithology, differential compaction and diagenetic processes

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, Erik

    2010-12-15

    Correlation of reservoir rocks is a challenge in many types of reservoirs around the world today. In a time where the focus has slowly shifted away from the giant fields, towards development of smaller, more marginal fields, the importance of addressing these challenges is increasing. The purpose of the thesis is to investigate the effects of lithology, diagenesis and differential compaction on correlation of reservoir architecture in a fluviodeltaic reservoir. To be able to address these issues several types of data, including seismic, core sections and petrophysical wireline logs, have been subjected to measurements, calculations and interpretations to be able to construct a sedimentological and sequence stratigraphic framework based on a reservoir reconstruction work flow. First, the regional and local (field wide) geological evolution for the Aare Formation in the Heidrun Field, offshore Mid-Norway, is elucidated, including evolution of the palaeodepositional environment and the prevailing depositional controlling factors. These studies included a facies description of studied wells based on core and wireline log data, and description/ interpretation of the reservoir sequence stratigraphy. From these studies eight facies associations have been identified and described, indicating a fluvial-deltaic depositional environment. A sequence stratigraphic model based on these facies associations is suggested for the studied well data and includes five candidate sequence boundaries and eight flooding surfaces, including a marine flooding surface. Four of these surfaces are interpreted as allogeneic, suggesting regional base level change, whereas the remaining nine surfaces are suggested as resulting from local, autogenic factors. Next, the compact ability of the identified facies associations was quantified in a diagenesis study using optical microscopy, SEM micro-probe measurements and XRD analyses. The para genetic sequence proposed suggests that abundant early

  10. Internal structure of fault zones in geothermal reservoirs: Examples from palaeogeothermal fields and potential host rocks

    Science.gov (United States)

    Leonie Philipp, Sonja; Reyer, Dorothea; Meier, Silke; Bauer, Johanna F.; Afşar, Filiz

    2014-05-01

    Fault zones commonly have great effects on fluid transport in geothermal reservoirs. During fault slip all the pores and small fractures that meet with the slip plane become interconnected so that the inner part of the fault, the fault core, consisting of breccia or gouge, may suddenly develop a very high permeability. This is evidenced, for example by networks of mineral veins in deeply eroded fault zones in palaeogeothermal fields. Inactive faults, however, may have low permeabilities and even act as flow barriers. In natural and man-made geothermal reservoirs, the orientation of fault zones in relation to the current stress field and their internal structure needs be known as accurately as possible. One reason is that the activity of the fault zone depends on its angle to the principal stress directions. Another reason is that the outer part of a fault zone, the damage zone, comprises numerous fractures of various sizes. Here we present field examples of faults, and associated joints and mineral veins, in palaeogeothermal fields, and potential host rocks for man-made geothermal reservoirs, respectively. We studied several localities of different stratigraphies, lithologies and tectonic settings: (1) 58 fault zones in 22 outcrops from Upper Carboniferous to Upper Cretaceous in the Northwest German Basin (siliciclastic, carbonate and volcanic rocks); (2) 16 fault zones in 9 outcrops in Lower Permian to Middle Triassic (mainly sandstone, limestone and granite) in the Upper Rhine Graben; and (3) 74 fault zones in two coastal sections of Upper Triassic and Lower Jurassic age (mudstones and limestone-marl alternations) in the Bristol Channel Basin, UK. (1) and (2) are outcrop analogues of geothermal reservoir horizons, (3) represent palaeogeothermal fields with mineral veins. The field studies in the Northwest German Basin (1) show pronounced differences between normal-fault zones in carbonate and clastic rocks. In carbonate rocks clear damage zones occur that are

  11. Inverse Problems in Geosciences: Modelling the Rock Properties of an Oil Reservoir

    DEFF Research Database (Denmark)

    Lange, Katrine

    the probability that a model adhere to prior knowledge by having specific multiple-point statistics, for instance, learned from a training image. Existing methods efficiently sample an a priori probability density function to create a set of acceptable models; but they cannot evaluate the probability of a model......Even the most optimistic forecasts predict that Danish oil production will decrease by 80% in the period between 2006 and 2040, and only a strong innovative technological effort can change that. Due to the geological structures of the subsurface in the Danish part of the North Sea, Denmark...... of the subsurface of the reservoirs. Hence the focus of this work has been on acquiring models of spatial parameters describing rock properties of the subsurface using geostatistical a priori knowledge and available geophysical data. Such models are solutions to often severely under-determined, inverse problems...

  12. Physical properties of rocks and aqueous fluids at conditions simulating near- and supercritical reservoirs

    Science.gov (United States)

    Kummerow, Juliane; Raab, Siegfried

    2016-04-01

    The growing interest in exploiting supercritical geothermal reservoirs calls for a thorough identification and understanding of physico-chemical processes occuring in geological settings with a high heat flow. In reservoir engineering, electrical sounding methods are common geophysical exploration and monitoring tools. However, a realistic interpretation of field measurements is based on the knowledge of both, the physical properties of the rock and those of the interacting fluid at defined temperature and pressure conditions. Thus, laboratory studies at simulated in-situ conditions provide a link between the field data and the material properties in the depth. The physico-chemical properties of fluids change dramatically above the critical point, which is for pure water 374.21 °C and 221.2 bar. In supercritical fluids mass transfer and diffusion-controlled chemical reactions are enhanced and cause mineral alterations. Also, ion mobility and ion concentration are affected by the change of physical state. All this cause changes in the electrical resistivity of supercritical fluids and may have considerable effects on the porosity and hydraulic properties of the rocks they are in contact with. While there are some datasets available for physical and chemical properties of water and single component salt solutions above their critical points, there exist nearly no data for electrical properties of mixed brines, representing the composition of natural geothermal fluids. Also, the impact of fluid-rock interactions on the electrical properties of multicomponent fluids in a supercritical region is scarcely investigated. For a better understanding of fluid-driven processes in a near- and supercritical geological environment, in the framework of the EU-funded FP7 program IMAGE we have measured (1) the electrical resistivity of geothermal fluids and (2) physical properties of fluid saturated rock samples at simulated in-situ conditions. The permeability and electrical

  13. Economic modeling of electricity production from hot dry rock geothermal reservoirs: methodology and analyses. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cummings, R.G.; Morris, G.E.

    1979-09-01

    An analytical methodology is developed for assessing alternative modes of generating electricity from hot dry rock (HDR) geothermal energy sources. The methodology is used in sensitivity analyses to explore relative system economics. The methodology used a computerized, intertemporal optimization model to determine the profit-maximizing design and management of a unified HDR electric power plant with a given set of geologic, engineering, and financial conditions. By iterating this model on price, a levelized busbar cost of electricity is established. By varying the conditions of development, the sensitivity of both optimal management and busbar cost to these conditions are explored. A plausible set of reference case parameters is established at the outset of the sensitivity analyses. This reference case links a multiple-fracture reservoir system to an organic, binary-fluid conversion cycle. A levelized busbar cost of 43.2 mills/kWh ($1978) was determined for the reference case, which had an assumed geothermal gradient of 40/sup 0/C/km, a design well-flow rate of 75 kg/s, an effective heat transfer area per pair of wells of 1.7 x 10/sup 6/ m/sup 2/, and plant design temperature of 160/sup 0/C. Variations in the presumed geothermal gradient, size of the reservoir, drilling costs, real rates of return, and other system parameters yield minimum busbar costs between -40% and +76% of the reference case busbar cost.

  14. Discovery and Significance of High CH4 Primary Fluid Inclusions in Reservoir Volcanic Rocks of the Songliao Basin, NE China

    Institute of Scientific and Technical Information of China (English)

    WANG Pujun; HOU Qijun; WANG Keyong; CHEN Shumin; CHENG Rihui; LIU Wanzhu; LI Quanlin

    2007-01-01

    Comparing compositions of the fluid inclusions in volcanic rocks to the contents and isotopes of the gases in corresponding volcanic reservoirs using microthermometry, Raman microspectroscopy and mass spectrum analysis, we found that: (1) up to 82 mole% methane exists in the primary inclusions hosted in the reservoir volcanic rocks; (2) high CH4 inclusions recognized in the volcanic rocks correspond to CH4-bearing CO2 reservoirs that are rich in helium and with a high 3He/4He ratio and which show reversed order of δ13C in alkane; (3) in gas reservoirs of such abiotic methane (>80%)and a mix of CH4 and CO2, the enclosed content of CH4 in the volcanic inclusions is usually below 42mole%, and the reversed order of δ13C in alkane is sometimes irregular in the corresponding gas pools;(4) a glassy inclusion with a homogeneous temperature over 900℃ also contains a small portion of CH4although predominantly CO2. This affinity between gas pool and content of inclusion in the same volcanic reservoirs demonstrates that magma-originated gases, both CH4 and CO2, have contributed significantly to the corresponding gas pools and that the assumed hydrocarbon budget of the bulk earth might be much larger than conventionally supposed.

  15. Wettability evaluation of a carbonate reservoir rock from core to pore level

    Energy Technology Data Exchange (ETDEWEB)

    Al-Yousef, H.Y.; Lichaa, P.M.; Al-Kaabi, A.U.; Alpustun, H.

    1995-10-01

    Wettability evaluation was performed during stags of as received, cleaned, and restored states on core samples form a Saudi Arabian carbonate reservoir. The wettability behavior from the chemistry of brine-oil-carbonate rock interaction was found to be neutral to slightly oil-wet. The pore-size distribution obtained from mercury injection data indicated that about 15--20 percent of the pore volume is not accessible to asphaltene particles in the crude oil. Therefore a mixed-wettability state can exist. These results were confirmed by the evaluation of the wettability of the cores using USBM and Amott techniques. The wettability at the pore level was studied using Cryo-Scanning Electron Microscopy. Rock samples were examined at irreducible water and residual oil saturations during cleaned and restored states. At irreducible water saturation, both oil and brine were present in the intergranular macroporosity and intragranular macropores and micropores. At residual oil saturation,oil was found in the form of isolated globules in the cleaned case. After aging, the oil is more loosely distributed in the porosity and generally contacts the pore walls. This indicates an evolution toward oil wetness with aging. These results are in agreement with the changes of wettability indices obtained using USBM technique.

  16. Rational Rock Physics for Improved Velocity Prediction and Reservoir Properties Estimation for Granite Wash (Tight Sands in Anadarko Basin, Texas

    Directory of Open Access Journals (Sweden)

    Muhammad Z. A. Durrani

    2014-01-01

    Full Text Available Due to the complex nature, deriving elastic properties from seismic data for the prolific Granite Wash reservoir (Pennsylvanian age in the western Anadarko Basin Wheeler County (Texas is quite a challenge. In this paper, we used rock physics tool to describe the diagenesis and accurate estimation of seismic velocities of P and S waves in Granite Wash reservoir. Hertz-Mindlin and Cementation (Dvorkin’s theories are applied to analyze the nature of the reservoir rocks (uncemented and cemented. In the implementation of rock physics diagnostics, three classical rock physics (empirical relations, Kuster-Toksöz, and Berryman models are comparatively analyzed for velocity prediction taking into account the pore shape geometry. An empirical (VP-VS relationship is also generated calibrated with core data for shear wave velocity prediction. Finally, we discussed the advantages of each rock physics model in detail. In addition, cross-plots of unconventional attributes help us in the clear separation of anomalous zone and lithologic properties of sand and shale facies over conventional attributes.

  17. Multi-Attribute Seismic/Rock Physics Approach to Characterizing Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2004-11-30

    Most current seismic methods to seismically characterize fractures in tight reservoirs depend on a few anisotropic wave propagation signatures that can arise from aligned fractures. While seismic anisotropy can be a powerful fracture diagnostic, a number of situations can lessen its usefulness or introduce interpretation ambiguities. Fortunately, laboratory and theoretical work in rock physics indicates that a much broader spectrum of fracture seismic signatures can occur, including a decrease in P- and S-wave velocities, a change in Poisson's ratio, an increase in velocity dispersion and wave attenuation, as well as well as indirect images of structural features that can control fracture occurrence. The goal of this project was to demonstrate a practical interpretation and integration strategy for detecting and characterizing natural fractures in rocks. The approach was to exploit as many sources of information as possible, and to use the principles of rock physics as the link among seismic, geologic, and log data. Since no single seismic attribute is a reliable fracture indicator in all situations, the focus was to develop a quantitative scheme for integrating the diverse sources of information. The integrated study incorporated three key elements: The first element was establishing prior constraints on fracture occurrence, based on laboratory data, previous field observations, and geologic patterns of fracturing. The geologic aspects include analysis of the stratigraphic, structural, and tectonic environments of the field sites. Field observations and geomechanical analysis indicates that fractures tend to occur in the more brittle facies, for example, in tight sands and carbonates. In contrast, strain in shale is more likely to be accommodated by ductile flow. Hence, prior knowledge of bed thickness and facies architecture, calibrated to outcrops, are powerful constraints on the interpreted fracture distribution. Another important constraint is that

  18. Dynamic reservoir characterization using 4D multicomponent seismic data and rock physics modeling at Delhi Field, Louisiana

    Science.gov (United States)

    Carvajal Meneses, Carla C.

    Pore pressure and CO2 saturation changes are important to detect and quantify for maximizing oil recovery in Delhi Field. Delhi Field is a enhanced oil recovery (EOR) project with active monitoring by 4D multicomponent seismic technologies. Dynamic rock physics modeling integrates the rich dataset of core, well logs, petrographic thin sections and facies providing a link between reservoir and elastic properties. The dynamic modeling in this high porosity sandstone reservoir shows that P-wave velocity is more sensitive to CO2 saturation while S-wave velocity is more sensitive to pore pressure changes. I use PP and PS seismic data to jointly invert for Vp=Vs ratio and acoustic impedance. This technique has the advantage of adding more information to the non-unique inversion problem. Combining the inversion results from the monitor surveys of June 2010 and August 2011 provides acoustic impedance and Vp=Vs percentage differences. The time-lapse inverted response enables dynamic characterization of the reservoir by fitting the predicted dynamic models (calibrated at the wells). Dynamic reservoir characterization adds value in this stratigraphic complex reservoir. The results indicate that reservoir heterogeneities and pore pressure gradients control the CO2 flow within the Paluxy reservoir. Injectors 148-2 and 140-1 showed CO2 is moving downdip following a distributary channel induced by differential pressure from an updip injector or a barrier caused by a heterogeneity in the reservoir. CO2 anomalies located above the Paluxy injector 148-2 indicates that CO2 is moving from the Paluxy up into the Tuscaloosa Formation. My work demonstrates that reservoir monitoring is necessary for reservoir management at Delhi Field.

  19. MULTIDISCIPLINARY IMAGING OF ROCK PROPERTIES IN CARBONATE RESERVOIRS FOR FLOW-UNIT TARGETING

    Energy Technology Data Exchange (ETDEWEB)

    Stephen C. Ruppel

    2005-02-01

    Despite declining production rates, existing reservoirs in the US contain large quantities of remaining oil and gas that constitute a huge target for improved diagnosis and imaging of reservoir properties. The resource target is especially large in carbonate reservoirs, where conventional data and methodologies are normally insufficient to resolve critical scales of reservoir heterogeneity. The objectives of the research described in this report were to develop and test such methodologies for improved imaging, measurement, modeling, and prediction of reservoir properties in carbonate hydrocarbon reservoirs. The focus of the study is the Permian-age Fullerton Clear Fork reservoir of the Permian Basin of West Texas. This reservoir is an especially appropriate choice considering (a) the Permian Basin is the largest oil-bearing basin in the US, and (b) as a play, Clear Fork reservoirs have exhibited the lowest recovery efficiencies of all carbonate reservoirs in the Permian Basin.

  20. Sequential extraction and compositional analysis of oil-bearing fluid inclusions in reservoir rocks from Kuche Depression, Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The free oils, adsorbed oils and oil-bearing fluid inclusions have been extracted separately and analyzed by GC and GC-MS in reservoir rock samples collected from the Kuche Depression. The results demonstrate that the molecular compositions of oil-bearing fluid inclusions are significantly different from those of the free oils (the current oils). Compared with the current oil, the oil-bearing fluid inclusions are characterized by relatively high values of parameters Pr/nC17and Ph/nC18, low values of Pr/Ph, hopanes/steranes, C30-diahopane/C30-hopane and Ts/Tm, low content of C29Ts terpane and high maturities as indicated by C29 steranes 20S/(20R+20S). In addition, the oil-bearing fluid inclusions correlate very well with the oils in northern and central Tarim Basin, which were derived from Cambrian-Ordovician marine source rocks. The adsorbedoils appear to be an intermediate type between free oils and oil-bearing fluid inclusions. The above analytical data indicate that there are at least two oil-charging episodes for these reservoir rock samples. The early charging oils were derived from Cambrian-Ordovician marine source rocks, and the later charging oils, from Triassic-Jurassic terrestrial source rocks. The primary marine oils were overwhelmingly diluted by the following terrestrial oils.

  1. Multi-Attribute Seismic/Rock Physics Approach to Characterizing Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2004-11-30

    Most current seismic methods to seismically characterize fractures in tight reservoirs depend on a few anisotropic wave propagation signatures that can arise from aligned fractures. While seismic anisotropy can be a powerful fracture diagnostic, a number of situations can lessen its usefulness or introduce interpretation ambiguities. Fortunately, laboratory and theoretical work in rock physics indicates that a much broader spectrum of fracture seismic signatures can occur, including a decrease in P- and S-wave velocities, a change in Poisson's ratio, an increase in velocity dispersion and wave attenuation, as well as well as indirect images of structural features that can control fracture occurrence. The goal of this project was to demonstrate a practical interpretation and integration strategy for detecting and characterizing natural fractures in rocks. The approach was to exploit as many sources of information as possible, and to use the principles of rock physics as the link among seismic, geologic, and log data. Since no single seismic attribute is a reliable fracture indicator in all situations, the focus was to develop a quantitative scheme for integrating the diverse sources of information. The integrated study incorporated three key elements: The first element was establishing prior constraints on fracture occurrence, based on laboratory data, previous field observations, and geologic patterns of fracturing. The geologic aspects include analysis of the stratigraphic, structural, and tectonic environments of the field sites. Field observations and geomechanical analysis indicates that fractures tend to occur in the more brittle facies, for example, in tight sands and carbonates. In contrast, strain in shale is more likely to be accommodated by ductile flow. Hence, prior knowledge of bed thickness and facies architecture, calibrated to outcrops, are powerful constraints on the interpreted fracture distribution. Another important constraint is that

  2. Nano-scale experimental investigation of in-situ wettability and spontaneous imbibition in ultra-tight reservoir rocks

    Science.gov (United States)

    Akbarabadi, Morteza; Saraji, Soheil; Piri, Mohammad; Georgi, Dan; Delshad, Mohammad

    2017-09-01

    We investigated spontaneous imbibition behavior, three-dimensional fluid occupancy maps, and in-situ wettability at the nano scale in five ultra-tight and shale reservoir rock samples. For this purpose, we developed a novel technique by integrating a custom-built in-situ miniature fluid-injection module with a non-destructive high-resolution X-ray imaging system. Small cylindrical core samples (15-60 μm in diameter) were prepared from reservoir rocks using Focused-Ion Beam (FIB) milling technique. The pore network inside the samples were first characterized using ultra-high resolution three-dimensional images obtained at initial state by X-ray nano-tomography (Nano-CT) and FIB-Scanning Electron Microscopy (FIB-SEM) techniques at the nano scale. The petrophysical parameters, including porosity, permeability, pore-size distribution, and organic content were computed for each sample using image analysis. We then performed series of imbibition experiments using brine, oil, and surfactant solutions on each core sample. We observed that both oil and brine phases spontaneously imbibe into the pore network of the rock samples at various quantities. We also, for the first time, examined fluid distribution in individual pores and found a complex wettability behavior at the pore scale in the reservoir rock samples. Three pore types were identified with water-wet, oil-wet, and fractionally-wet behaviors. This work opens a new path to developing an improved understanding of the pore-level physics involved in multi-phase flow and transport not only in tight rock samples but also in other nanoporous material used in different science and engineering applications.

  3. Structural and petrophysical characterization: from outcrop rock analogue to reservoir model of deep geothermal prospect in Eastern France

    Science.gov (United States)

    Bertrand, Lionel; Géraud, Yves; Diraison, Marc; Damy, Pierre-Clément

    2017-04-01

    The Scientific Interest Group (GIS) GEODENERGIES with the REFLET project aims to develop a geological and reservoir model for fault zones that are the main targets for deep geothermal prospects in the West European Rift system. In this project, several areas are studied with an integrated methodology combining field studies, boreholes and geophysical data acquisition and 3D modelling. In this study, we present the results of reservoir rock analogues characterization of one of these prospects in the Valence Graben (Eastern France). The approach used is a structural and petrophysical characterization of the rocks outcropping at the shoulders of the rift in order to model the buried targeted fault zone. The reservoir rocks are composed of fractured granites, gneiss and schists of the Hercynian basement of the graben. The matrix porosity, permeability, P-waves velocities and thermal conductivities have been characterized on hand samples coming from fault zones at the outcrop. Furthermore, fault organization has been mapped with the aim to identify the characteristic fault orientation, spacing and width. The fractures statistics like the orientation, density, and length have been identified in the damaged zones and unfaulted blocks regarding the regional fault pattern. All theses data have been included in a reservoir model with a double porosity model. The field study shows that the fault pattern in the outcrop area can be classified in different fault orders, with first order scale, larger faults distribution controls the first order structural and lithological organization. Between theses faults, the first order blocks are divided in second and third order faults, smaller structures, with characteristic spacing and width. Third order fault zones in granitic rocks show a significant porosity development in the fault cores until 25 % in the most locally altered material, as the damaged zones develop mostly fractures permeabilities. In the gneiss and schists units, the

  4. Imaging techniques applied to the study of fluids in porous media. Scaling up in Class 1 reservoir type rock

    Energy Technology Data Exchange (ETDEWEB)

    Tomutsa, L.; Brinkmeyer, A.; Doughty, D.

    1993-04-01

    A synergistic rock characterization methodology has been developed. It derives reservoir engineering parameters from X-ray tomography (CT) scanning, computer assisted petrographic image analysis, minipermeameter measurements, and nuclear magnetic resonance imaging (NMRI). This rock characterization methodology is used to investigate the effect of small-scale rock heterogeneity on oil distribution and recovery. It is also used to investigate the applicability of imaging technologies to the development of scaleup procedures from core plug to whole core, by comparing the results of detailed simulations with the images ofthe fluid distributions observed by CT scanning. By using the rock and fluid detailed data generated by imaging technology describe, one can verify directly, in the laboratory, various scaling up techniques. Asan example, realizations of rock properties statistically and spatially compatible with the observed values are generated by one of the various stochastic methods available (fuming bands) and are used as simulator input. The simulation results were compared with both the simulation results using the true rock properties and the fluid distributions observed by CT. Conclusions regarding the effect of the various permeability models on waterflood oil recovery were formulated.

  5. Reservoir condition special core analyses and relative permeability measurements on Almond formation and Fontainebleu sandstone rocks

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, D.

    1993-11-01

    This report describes the results from special core analyses and relative permeability measurements conducted on Almond formation and Fontainebleu sandstone plugs. Almond formation plug tests were performed to evaluate multiphase, steady-state,reservoir-condition relative permeability measurement techniques and to examine the effect of temperature on relative permeability characteristics. Some conclusions from this project are as follows: An increase in temperature appeared to cause an increase in brine relative permeability results for an Almond formation plug compared to room temperature results. The plug was tested using steady-state oil/brine methods. The oil was a low-viscosity, isoparaffinic refined oil. Fontainebleu sandstone rock and fluid flow characteristics were measured and are reported. Most of the relative permeability versus saturation results could be represented by one of two trends -- either a k{sub rx} versus S{sub x} or k{sub rx} versus Sy trend where x and y are fluid phases (gas, oil, or brine). An oil/surfactant-brine steady-state relative permeability test was performed to examine changes in oil/brine relative permeability characteristics from changes in fluid IFTS. It appeared that, while low interfacial tension increased the aqueous phase relative permeability, it had no effect on the oil relative permeability. The BOAST simulator was modified for coreflood simulation. The simulator was useful for examining effects of variations in relative permeability and capillary pressure functions. Coreflood production monitoring and separator interface level measurement techniques were developed using X-ray absorption, weight methods, and RF admittance technologies. The three types of separators should be useful for routine and specialized core analysis applications.

  6. ADVANCED CHARACTERIZATION OF FRACTURED RESERVOIRS IN CARBONATE ROCKS: THE MICHIGAN BASIN

    Energy Technology Data Exchange (ETDEWEB)

    James R. Wood; William B. Harrison

    2002-12-01

    Michigan Basin, and it is crucial in developing reservoir quality rocks in some fields. Data on the occurrence of dolomite was extracted from driller's reports for all reported occurrences in Michigan, nearly 50 fields and over 500 wells. A digital database was developed containing the geographic location of all these wells (latitude-longitude) as well as the elevation of the first encounter of dolomite in the field/reservoir. Analysis shows that these dolomite occurrences are largely confined to the center of the basin, but with some exceptions, such as N. Adams Field. Further, some of the dolomite occurrences show a definite relationship to the fracture pattern described above, suggesting a genetic relationship that needs further work. Other accomplishments of this past reporting period include obtaining a complete land grid for the State of Michigan and further processing of the high and medium resolution DEM files. We also have measured new fluid inclusion data on dolomites from several fields that suggest that the dolomitization occurred at temperatures between 100 and 150 C. Finally, we have extracted the lithologic data for about 5000 wells and are in the process of integrating this data into the overall model for the Michigan Basin.

  7. ECO-Report - Fire recovery in the Bitterroot: "It’s a lot of work!"

    Science.gov (United States)

    Janie Canton-Thompson; Sharon Ritter; Dave Campbell; Julie Schreck; Peter Kolb; Brooke Thompson; Hans Zuuring; Alan Watson; Yvette Ortega; Kevin McKelvey; Elaine Kennedy Sutherland; Greg Jones

    2002-01-01

    ECO-Report is an annual Rocky Mountain Research Station (RMRS) publication which contains a set of articles showcasing the Bitterroot Ecosystem Management Research Project (BEMRP) research projects and activities. The articles are concise, user-friendly, and designed to inform a broad range of audiences interested in ecosystem management. Articles featured in...

  8. Exploration, Drilling and Development Operations in the Bottle Rock Area of the Geysers Steam Field, With New Geologic Insights and Models Defining Reservoir Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hebein, Jeffrey J.

    1983-12-15

    MCR Geothermal Corporation pioneered successful exploratiory drilling the Bottle Rock area of the Geysers Steam Field in 1976. The wellfield is characterized by a deep reservoir with varied flowrates, temperatures, pressures, and stem chemistries being quite acceptable. More detailed reservoir engineering tests will follow as production commences.

  9. Influence of filling-drawdown cycles of the Three Gorges reservoir on deformation and failure behaviors of anaclinal rock slopes in the Wu Gorge

    Science.gov (United States)

    Huang, Da; Gu, Dong Ming

    2017-10-01

    The upper Wu Gorge on the Yangtze River has been the site of tens of reservoir-induced landslides since the filling of the Three Gorges reservoir in 2003. These landslides have been occurring in heavily fractured carbonate rock materials along the rim of the reservoir in the Wu Gorge. A detailed investigation was carried out to examine the influence of reservoir operations (filling and drawdown) on slope stabilities in the upper Wu Gorge. Field investigations reveal many collapses of various types occurred at the toe of the anaclinal rock slopes, owing to the long-term intensive river erosion caused by periodic fluctuation of the reservoir level. Analysis of data from deformation monitoring suggests that the temporal movement of the slopes shows seasonal fluctuations that correlate with reservoir levels and drawdown conditions, with induced slope acceleration peaking when reservoir levels are lowest. This may illustrate that the main mechanism is the reservoir drawdown, which induces an episodic seepage force in the highly permeable materials at the slope toes, and thus leads to the episodic rockslides. The coupled hydraulic-mechanical (HM) modeling of the G2 landslide, which occurred in 2008, shows that collapse initiated at the submerged slope toe, which then caused the upper slope to collapse in a rock topple-rock slide pattern. The results imply that preventing water erosion at the slope toe might be an effective way for landslide prevention in the study area.

  10. Optimization of Vertical Well Placement for Oil Field Development Based on Basic Reservoir Rock Properties using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Tutuka Ariadji

    2012-07-01

    Full Text Available Comparing the quality of basic reservoir rock properties is a common practice to locate new infills or development wells for optimizing an oil field development using a reservoir simulation. The conventional technique employs a manual trial and error process to find new well locations, which proves to be time-consuming, especially, for a large field. Concerning this practical matter, an alternative in the form of a robust technique was introduced in order that time and efforts could be reduced in finding best new well locations capable of producing the highest oil recovery. The objective of the research was to apply Genetic Algorithm (GA in determining wells locations using reservoir simulation to avoid the manual conventional trial and error method. GA involved the basic rock properties, i.e., porosity, permeability, and oil saturation, of each grid block obtained from a reservoir simulation model, which was applied into a newly generated fitness function formulated through translating the common engineering practice in the reservoir simulation into a mathematical equation and then into a computer program. The maximum of the fitness value indicated a final searching of the best grid location for a new well location. In order to evaluate the performance of the generated GA program, two fields that had different production profile characteristics, namely the X and Y fields, were applied to validate the proposed method. The proposed GA method proved to be a robust and accurate method to find the best new well locations for field development. The key success of this proposed GA method is in the formulation of the objective function.

  11. The impact of reservoir conditions and rock heterogeneity on multiphase flow in CO2-brine-sandstone systems

    Science.gov (United States)

    Krevor, S. C.; Reynolds, C. A.; Al-Menhali, A.; Niu, B.

    2015-12-01

    Capillary strength and multiphase flow are key for modeling CO2 injection for CO2 storage. Past observations of multiphase flow in this system have raised important questions about the impact of reservoir conditions on flow through effects on wettability, interfacial tension and fluid-fluid mass transfer. In this work we report the results of an investigation aimed at resolving many of these outstanding questions for flow in sandstone rocks. The drainage capillary pressure, drainage and imbibition relative permeability, and residual trapping [1] characteristic curves have been characterized in Bentheimer and Berea sandstone rocks across a pressure range 5 - 20 MPa, temperatures 25 - 90 C and brine salinities 0-5M NaCl. Over 30 reservoir condition core flood tests were performed using techniques including the steady state relative permeability test, the semi-dynamic capillary pressure test, and a new test for the construction of the residual trapping initial-residual curve. Test conditions were designed to isolate effects of interfacial tension, viscosity ratio, density ratio, and salinity. The results of the tests show that, in the absence of rock heterogeneity, reservoir conditions have little impact on flow properties, consistent with continuum scale multiphase flow theory for water wet systems. The invariance of the properties is observed, including transitions of the CO2 from a gas to a liquid to a supercritical fluid, and in comparison with N2-brine systems. Variations in capillary pressure curves are well explained by corresponding changes in IFT although some variation may reflect small changes in wetting properties. The low viscosity of CO2at certain conditions results in sensitivity to rock heterogeneity. We show that (1) heterogeneity is the likely source of uncertainty around past relative permeability observations and (2) that appropriate scaling of the flow potential by a quantification of capillary heterogeneity allows for the selection of core flood

  12. Effect of Water Washing on Hydrocarbon Compositions of Petropleum Sandstone Reservoir Rocks in Tarim Basin,NW China

    Institute of Scientific and Technical Information of China (English)

    张敏; 张俊

    2000-01-01

    Gross compositions and distribution of saturated and aromatic hydrocarbons in Carboniferous sandstone reservoire rocks in oil and water zones for Tzhong-10 well of the Zhongyang Uplift in the Tarim Basin were studied in dteail by means of Rock-Eval Pyrolysis,thin-chromatograph-flame ionization detection(TLC-FID),gas chromatography,gas chromatography-mass spectrometry.The results suggest that the gross composition of reservoir hydrocarbons between the oil zone and the water zone show significant differences,Water wahing has a dramatic effect on saturated hydrocarbon blomarkers,especially drimane series compounds,Drimane series compounds in the water zone have been depleted completely.However,the contents of tricyclic iterpanes and pentacyclic triterpanes tend to decrease slightly,but the water-zone reservoir hydrocarbons contian a large amount of gammacerane.This suggests that gammacerane be more resistant to water washing than diterpanes and homohopanes.The contents of pregnane,homopregrane,diasteranes relastively decrease as a result of water washing.Water washing has a noticeable effect on polycyclic aromatic hydrocarbon compounds,especially aromatic sulfur compounds,and the contents of dibenzothiophene series compounds and benzonaplyiothipophene decrease significantly as a result of water washing.However,the conterts of bicyclic and tricyclic aromatic hydrocarbons decrase slightly and those of tetracyclic and pentacyclic aromatic hydrocarbons,especially benzofluoranthene and benzopyrenes,increase markedly owing to adecrease in light aromatie hydrocarbons as a result of water washing.

  13. Sedimentary Facies and Distribution of Reservoir Rocks from the Feixianguan Formation in the Daxian-Xuanhan Region, NE Sichuan

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sichuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Chongqing marine basin and Guangyuan-Wangcang marine basin. Outcrops, well logs and seismic data have disclosed that three sedimentary facies can be identified for the formation: open platform,platform exposed shoal and restricted platform facies. During the early stage of deposition of the Feixianguan Formation, there existed a sedimentary framework all the same as the Late Permian one:open platform in the west, and platform exposed shoal, restricted platform and open platform eastwards. The gradual increase of the shoal area permitted eastward migration of the shoal facies.During the deposition of the third member of the Feixianguan Formation, the study area was invaded by temporary transgressions. Till the deposition of the fourth member of the formation, the study area was prevailed over the unified restricted platform deposits, as indicated by the sedimentary model for the typical carbonate platform shoal deposits. The reservoir rocks in the Feixianguan Formation consist mostly of solution opening dolostone, and the rock types are assembled by oolitic dolostone, residual oolitic dolostone and sucrosic residual oolitic medium- to coarse-grained dolostone. The deep and shallow dual laterologs show relatively high resistivity, clear amplitude differences and time difference saltation of acoustic waves in some intervals. The seismic responses are indicated by low-frequency and highly variable amplitudes and chaotic reflection configurations. The reservoir rocks are characterized by high porosity-high permeability and medium porosity-medium permeability, showing a marked correlation between porosity and permeability. Solution openings are extremely developed in the reservoir rocks, including cast pores, intergranular solution openings, intercrystal pores, intercrystal solution openings

  14. 4D reservoir characterization using well log data for feasible CO2-enhanced oil recovery at Ankleshwar, Cambay Basin - A rock physics diagnostic and modeling approach

    Science.gov (United States)

    Ganguli, Shib Sankar; Vedanti, Nimisha; Dimri, V. P.

    2016-12-01

    In recent years, rock physics modeling has become an integral part of reservoir characterization as it provides the fundamental relationship between geophysical measurements and reservoir rock properties. These models are also used to quantify the effect of fluid saturation and stress on reservoir rocks by tracking the changes in elastic properties during production. Additionally, various rock physics models can be applied to obtain the information of rock properties away from existing drilled wells, which can play a crucial role in the feasibility assessment of CO2-enhanced oil recovery (EOR) operation at field. Thus, the objective of this study is to develop a rock-physics model of the Ankleshwar reservoir to predict the reservoir response under CO2-EOR. The Ankleshwar oil field is a mature field situated in Cambay Basin (Western India) that witnessed massive peripheral water flooding for around 40 years. Since the field was under water flooding for a long term, reasonable changes in reservoir elastic properties might have occurred. To identify potential reservoir zone with significant bypassed (or residual) oil saturation, we applied the diagnostic rock physics models to two available wells from the Ankleshwar oil field. The results clearly indicate transitions from clean sands to shaly sands at the base, and from sandy shale to pure shale at the top of the reservoir pay zone, suggesting a different seismic response at the top when compared to the base of the reservoir in both the wells. We also found that clay content and sorting affects the elastic properties of these sands, indicating different depositional scenario for the oil sands encountered in the Ankleshwar formation. Nevertheless, the rock physics template (RPT) analysis of the well data provides valuable information about the residual oil zone, a potential target for CO2-EOR. Further, a 4D reservoir characterization study has been conducted to assess the seismic detectability of CO2-EOR, and we

  15. Classification of bleaching patterns and controlling factors in reservoir-cap rock system: an example from SE Utah, USA

    Science.gov (United States)

    Ko, Kyoungtae; Kim, Young-Seog

    2015-04-01

    Recently, many studies on geological CO2 storage are being actively carried out to reduce the effect of global warming. For successful geological CO2 storage, it is important to understand the mechanisms of natural CO2 leakage. Especially, the characteristics of natural fluid flow are mainly controlled by faults and fractures, and it is one of the most important issues for geological CO2 storage projects. For this study, we studied various bleaching patterns around Green river, SE Utah, which can provide some evidences for fluid flow and leakage within geological media.The study area is consisted of Jurassic and Cretaceous sedimentary rocks. These sedimentary rocks are characterized by alternative layers of sand (reservoir rock) and mud/shale (cap rock). For the purpose of this study, we described and classified various bleaching patterns in the study area and we tried to find controlling factors related for each pattern. Based on the preliminary results, we divided the described bleaching patterns into three main categories; Dot Type, Line Type and Area Type. Our field observations indicate that the pattern of natural bleaching is strongly controlled by primary and secondary structures of the geological media. Bleached layers generally show much higher fracture density and higher permeability values than those of unbleached layers. Also, the more bleached layers, the more permeable layers. However, the layers with well-developed deformation bands tend to decrease permeability compared with the layers with well-developed fractures. The results of our preliminary study indicate that the fluid flow (CO2 leakage to the surface) characteristics are strongly dependent on lithological porosity and geologic structures such as mainly fracture density and aperture. Our results must be very useful in evaluation for site selection of CO2 sequestration, in particularly when assess CO2 leakage in a reservoir and cap rock system.

  16. Classification and quantification of pore shapes in sandstone reservoir rocks with 3-D X-ray micro-computed tomography

    Directory of Open Access Journals (Sweden)

    M. Schmitt

    2015-12-01

    Full Text Available Recent years have seen a growing interest in the characterization of the pore morphologies of reservoir rocks and how the spatial organization of pore traits affects the macro behaviour of rock-fluid systems. With the availability of 3-D high-resolution imaging (e.g. μ-CT, the detailed quantification of particle shapes has been facilitated by progress in computer science. Here, we show how the shapes of irregular rock particles (pores can be classified and quantified based on binary 3-D images. The methodology requires the measurement of basic 3-D particle descriptors and a shape classification that involves the similarity of artificial objects, which is based on main pore network detachments and 3-D sample sizes. The results were validated for three sandstones (S1, S2 and S3 from distinct reservoirs, and most of the pore shapes were found to be plate- and cube-like. Furthermore, this study generalizes a practical way to correlate specific particle shapes, such as rods, blades, cuboids, plates and cubes, to characterize asymmetric particles of any material type with 3-D image analysis.

  17. An integrated petrophysical and rock physics analysis to improve reservoir characterization of Cretaceous sand intervals in Middle Indus Basin, Pakistan

    Science.gov (United States)

    Azeem, Tahir; Chun, Wang Yan; MonaLisa; Khalid, Perveiz; Xue Qing, Liu; Ehsan, Muhammad Irfan; Jawad Munawar, Muhammad; Wei, Xie

    2017-03-01

    The sand intervals of the Lower Goru Formation of the Cretaceous age, widely distributed in the Middle and Lower Indus Basin of Pakistan, are proven reservoirs. However, in the Sawan gas field of the Middle Indus Basin, these sandstone intervals are very deep and extremely heterogeneous in character, which makes it difficult to discriminate lithologies and fluid saturation. Based on petrophysical analysis and rock physics modeling, an integrated approach is adopted to discriminate between lithologies and fluid saturation in the above-mentioned sand intervals. The seismic velocities are modeled using the Xu–White clay–sand mixing rock physics model. The calibrated rock physics model shows good consistency between measured and modeled velocities. The correlation between measured and modeled P and S wave velocities is 92.76% and 84.99%, respectively. This calibrated model has been successfully used to estimate other elastic parameters, even in those wells where both shear and sonic logs were missing. These estimated elastic parameters were cross-plotted to discriminate between the lithology and fluid content in the target zone. Cross plots clearly separate the shale, shaly sand, and gas-bearing sand clusters, which was not possible through conventional petrophysical analysis. These data clusters have been exported to the corresponding well for the purpose of interpolation between wells and to analyze the lateral and vertical variations in lithology and fluid content in the reservoir zone.

  18. Rock music : a living legend of simulation modelling solves a reservoir problem by playing a different tune

    Energy Technology Data Exchange (ETDEWEB)

    Cope, G.

    2008-07-15

    Tight sand gas plays are low permeability reservoirs that have contributed an output of 5.7 trillion cubic feet of natural gas per year in the United States alone. Anadarko Petroleum Corporation has significant production from thousands of wells in Texas, Colorado, Wyoming and Utah. Hydraulic fracturing is the key to successful tight sand production. Production engineers use modelling software to calculate a well stimulation program in which large volumes of water are forced under high pressure in the reservoir, fracturing the rock and creating high permeability conduits for the natural gas to escape. Reservoir engineering researchers at the University of Calgary, led by world expert Tony Settari, have improved traditional software modelling of petroleum reservoirs by combining fracture analysis with geomechanical processes. This expertise has been a valuable asset to Anadarko, as the dynamic aspect can have a significant effect on the reservoir as it is being drilled. The challenges facing reservoir simulation is the high computing time needed for analyzing fluid production based on permeability, porosity, gas and fluid properties along with geomechanical analysis. Another challenge has been acquiring high quality field data. Using Anadarko's field data, the University of Calgary researchers found that water fracturing creates vertical primary fractures, and in some cases secondary fractures which enhance permeability. However, secondary fracturing is not permanent in all wells. The newly coupled geomechanical model makes it possible to model fracture growth more accurately. The Society of Petroleum Engineers recently awarded Settari with an award for distinguished achievement in improving the technique and practice of finding and producing petroleum. 1 fig.

  19. Pore Fluid Effects on Shear Modulus in a Model of Heterogeneous Rocks, Reservoirs, and Granular Media

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, J G

    2005-03-23

    To provide quantitative measures of the importance of fluid effects on shear waves in heterogeneous reservoirs, a model material called a ''random polycrystal of porous laminates'' is introduced. This model poroelastic material has constituent grains that are layered (or laminated), and each layer is an isotropic, microhomogeneous porous medium. All grains are composed of exactly the same porous constituents, and have the same relative volume fractions. The order of lamination is not important because the up-scaling method used to determine the transversely isotropic (hexagonal) properties of the grains is Backus averaging, which--for quasi-static or long-wavelength behavior--depends only on the volume fractions and layer properties. Grains are then jumbled together totally at random, filling all space, and producing an overall isotropic poroelastic medium. The poroelastic behavior of this medium is then analyzed using the Peselnick-Meister-Watt bounds (of Hashin-Shtrikman type). We study the dependence of the shear modulus on pore fluid properties and determine the range of behavior to be expected. In particular we compare and contrast these results to those anticipated from Gassmann's fluid substitution formulas, and to the predictions of Mavko and Jizba for very low porosity rocks with flat cracks. This approach also permits the study of arbitrary numbers of constituents, but for simplicity the numerical examples are restricted here to just two constituents. This restriction also permits the use of some special exact results available for computing the overall effective stress coefficient in any two-component porous medium. The bounds making use of polycrystalline microstructure are very tight. Results for the shear modulus demonstrate that the ratio of compliance differences R (i.e., shear compliance changes over bulk compliance changes when going from drained to undrained behavior, or vice versa) is usually nonzero and can take a wide

  20. Integrated electromagnetic data investigation of a Mesozoic CO2 storage target reservoir-cap-rock succession, Svalbard

    Science.gov (United States)

    Beka, Thomas I.; Senger, Kim; Autio, Uula A.; Smirnov, Maxim; Birkelund, Yngve

    2017-01-01

    Recently acquired time-domain electromagnetic (TEM) and magnetotelluric (MT) data sets are utilized in the first electromagnetic (EM) characterization of a geological CO2 storage target site in Adventdalen, Arctic Norway. Combining the two EM data sets enabled to resolve the electrical resistivity structure of the target site better than either of the methods alone. 2D inverting the MT data in the audio period interval (0.003-1 s) with supporting input derived from the TEM data (0.01-10 ms) provided a geologically meaningful resistivity model that included information not previously evident from existing seismic and borehole data. The ca. 1.8 × 1 km 2D resistivity model displays a laterally constrained highly conductive anomaly (ca. 10 Ω m) at about 400-500 m depth, where reflectors of a parallel seismic section are concealed and core samples indicate a highly fractured décollement zone formed during Paleogene compression. The base of the permafrost is imaged at ca. 200 m depth. Synthetic inversion tests, however, suggest that this may be exaggerated by tens of meters, due to a thin conductive layer present approximately between 10 and 25 m depth. The resistivity model does not give indication for a fluid pathway we can connect to leakage, in line with water injection and leak-off tests in the reservoir and cap-rock, both of which indicate a sealing shale-dominated cap-rock separating an over-pressured compartment above the sealing shale from a severely under-pressured reservoir interval. The results we present indicate the advantage of integrating EM exploration techniques in a CO2 reservoir-cap-rock study to obtain a more complete picture.

  1. Combining water-rock interaction experiments with reaction path and reactive transport modelling to predict reservoir rock evolution in an enhanced geothermal system

    Science.gov (United States)

    Kuesters, Tim; Mueller, Thomas; Renner, Joerg

    2016-04-01

    Reliably predicting the evolution of mechanical and chemical properties of reservoir rocks is crucial for efficient exploitation of enhanced geothermal systems (EGS). For example, dissolution and precipitation of individual rock forming minerals often result in significant volume changes, affecting the hydraulic rock properties and chemical composition of fluid and solid phases. Reactive transport models are typically used to evaluate and predict the effect of the internal feedback of these processes. However, a quantitative evaluation of chemo-mechanical interaction in polycrystalline environments is elusive due to poorly constrained kinetic data of complex mineral reactions. In addition, experimentally derived reaction rates are generally faster than reaction rates determined from natural systems, likely a consequence of the experimental design: a) determining the rate of a single process only, e.g. the dissolution of a mineral, and b) using powdered sample materials and thus providing an unrealistically high reaction surface and at the same time eliminating the restrictions on element transport faced in-situ for fairly dense rocks. In reality, multiple reactions are coupled during the alteration of a polymineralic rocks in the presence of a fluid and the rate determining process of the overall reactions is often difficult to identify. We present results of bulk rock-water interaction experiments quantifying alteration reactions between pure water and a granodiorite sample. The rock sample was chosen for its homogenous texture, small and uniform grain size (˜0.5 mm in diameter), and absence of pre-existing alteration features. The primary minerals are plagioclase (plg - 58 vol.%), quartz (qtz - 21 vol.%), K-feldspar (Kfs - 17 vol.%), biotite (bio - 3 vol.%) and white mica (wm - 1 vol.%). Three sets of batch experiments were conducted at 200 ° C to evaluate the effect of reactive surface area and different fluid path ways using (I) powders of the bulk rock with

  2. Reservoir

    Directory of Open Access Journals (Sweden)

    M. Mokhtar

    2016-12-01

    Full Text Available Scarab field is an analog for the deep marine slope channels in Nile Delta of Egypt. It is one of the Pliocene reservoirs in West delta deep marine concession. Channel-1 and channel-2 are considered as main channels of Scarab field. FMI log is used for facies classification and description of the channel subsequences. Core data analysis is integrated with FMI to confirm the lithologic response and used as well for describing the reservoir with high resolution. A detailed description of four wells penetrated through both channels lead to define channel sequences. Some of these sequences are widely extended within the field under study exhibiting a good correlation between the wells. Other sequences were of local distribution. Lithologic sequences are characterized mainly by fining upward in Vshale logs. The repetition of these sequences reflects the stacking pattern and high heterogeneity of the sandstone reservoir. It also refers to the sea level fluctuation which has a direct influence to the facies change. In terms of integration of the previously described sequences with a high resolution seismic data a depositional model has been established. The model defines different stages of the channel using Scarab-2 well as an ideal analog.

  3. Reservoir Modeling of Carbonate on Fika Field: The Challenge to Capture the Complexity of Rock and Oil Types

    Directory of Open Access Journals (Sweden)

    Erawati Fitriyani Adji

    2014-09-01

    Full Text Available DOI: 10.17014/ijog.v1i2.181The carbonate on Fika Field has a special character, because it grew above a basement high with the thickness and internal character variation. To develop the field, a proper geological model which can be used in reservoir simulation was needed. This model has to represent the complexity of the rock type and the variety of oil types among the clusters. Creating this model was challenging due to the heterogeneity of the Baturaja Formation (BRF: Early Miocene reef, carbonate platform, and breccia conglomerate grew up above the basement with a variety of thickness and quality distributions. The reservoir thickness varies between 23 - 600 ft and 3D seismic frequency ranges from 1 - 80 Hz with 25 Hz dominant frequency. Structurally, the Fika Field has a high basement slope, which has an impact on the flow unit layering slope. Based on production data, each area shows different characteristics and performance: some areas have high water cut and low cumulative production. Oil properties from several clusters also vary in wax content. The wax content can potentially build up a deposit inside tubing and flow-line, resulted in a possible disturbance to the operation. Five well cores were analyzed, including thin section and XRD. Seven check-shot data and 3D seismic Pre-Stack Time Migration (PSTM were available with limited seismic resolution. A seismic analysis was done after well seismic tie was completed. This analysis included paleogeography, depth structure map, and distribution of reservoir and basement. Core and log data generated facies carbonate distribution and rock typing, defining properties for log analysis and permeability prediction for each zone. An Sw prediction for each well was created by J-function analysis. This elaborates capillary pressure from core data, so it is very similar to the real conditions. Different stages of the initial model were done i.e. scale-up properties, data analysis, variogram modeling

  4. Simulation of fluid-rock interactions in a geothermal basin. Final report. [QUAGMR (quasi-active geothermal reservoir)

    Energy Technology Data Exchange (ETDEWEB)

    Garg, S.K.; Blake, T.R.; Brownell, D.H. Jr.; Nayfeh, A.H.; Pritchett, J.W.

    1975-09-01

    General balance laws and constitutive relations are developed for convective hydrothermal geothermal reservoirs. A fully interacting rock-fluid system is considered; typical rock-fluid interactions involve momentum and energy transfer and the dependence of rock porosity and permeability upon the fluid and rock stresses. The mathematical model also includes multiphase (water/steam) effects. A simple analytical model is employed to study heat transfer into/or from a fluid moving in a porous medium. Numerical results show that for fluid velocities typical of geothermal systems (Reynolds number much less than 10), the fluid and the solid may be assumed to be in local thermal equilibrium. Mathematical formalism of Anderson and Jackson is utilized to derive a continuum species transport equation for flow in porous media; this method allows one to delineate, in a rigorous manner, the convective and diffusive mechanisms in the continuum representation of species transport. An existing computer program (QUAGMR) is applied to study upwelling of hot water from depth along a fault; the numerical results can be used to explain local temperature inversions occasionally observed in bore hole measurements.

  5. Fracture network growth for prediction of fracture characteristics and connectivity in tight reservoir rocks

    NARCIS (Netherlands)

    Barnhoorn, A.; Cox, S.F.

    2012-01-01

    Fracturing experiments on very low-porosity dolomite rocks shows a difference in growth of fracture networks by stress-driven fracturing and fluid-driven fracturing. Stress-driven fracture growth, in the absence of fluid pressure, initially forms fractures randomly throughout the rocks followed by g

  6. The use of predictive lithostratigraphy to significantly improve the ability to forecast reservoir and source rocks? Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    Doctor, R. D.; Moore, T. L.; Energy Systems

    2010-06-29

    The purpose of this CRADA, which ended in 2003, was to make reservoir and source rock distribution significantly more predictable by quantifying the fundamental controls on stratigraphic heterogeneity. To do this, the relationships among insolation, climate, sediment supply, glacioeustasy, and reservoir and source rock occurrence were investigated in detail. Work current at the inception of the CRADA had uncovered previously unrecognized associations among these processes and properties that produce a phenomenon that, when properly analyzed, will make lithostratigraphic variability (including texture, porosity, and permeability) substantially more understandable. Computer climate simulations of selected time periods, compared with the global distribution of paleoclimatic indicators, documented spatial and temporal climate changes as a function of insolation and provided quantitative changes in runoff, lake level, and glacioeustasy. The effect of elevation and climate on sediment yield was assessed numerically by analyzing digital terrain and climate data. The phase relationships of climate, yield, and glacioeustatic cycles from the Gulf of Mexico and/or other sedimentary basins were assessed by using lacunarity, a statistical technique.

  7. Tight Reservoir Properties Derived by Nuclear Magnetic Resonance, Mercury Porosimetry and Computed Microtomography Laboratory Techniques. Case Study of Palaeozoic Clastic Rocks

    Science.gov (United States)

    Krakowska, Paulina I.; Puskarczyk, Edyta

    2015-06-01

    Results of the nuclear magnetic resonance (NMR) investigations, mercury porosimetry measurements (MP) and computed microtomography (micro-CT), applied to the tight Palaeozoic rocks from the depths lower than 3000 m, were presented to estimate their reservoir potential. NMR signal analysis and interpretation were performed. Based on NMR driven models, permeability and Free Fluid Index were calculated for data sets divided into homogeneous clusters. Computerized mercury porosimetry results visualization and processing provided useful information, as the automatically determined Swanson parameter is correlated with petrophysical properties of rocks. Micro-CT enriched the image of porous space in qualitative and quantitative ways. Homogeneity of pore space structure was discussed using micro-CT approach. Integration of the results in the frame of reservoir parameters from standard laboratory methods and the modern ones resulted in the improvement of methodology for determining the old, deep-seated, hard sedimentary rocks reservoir potential.

  8. Mineral Dissolution and Precipitation due to Carbon Dioxide-Water-Rock Interactions: The Significance of Accessory Minerals in Carbonate Reservoirs (Invited)

    Science.gov (United States)

    Kaszuba, J. P.; Marcon, V.; Chopping, C.

    2013-12-01

    Accessory minerals in carbonate reservoirs, and in the caprocks that seal these reservoirs, can provide insight into multiphase fluid (CO2 + H2O)-rock interactions and the behavior of CO2 that resides in these water-rock systems. Our program integrates field data, hydrothermal experiments, and geochemical modeling to evaluate CO2-water-rock reactions and processes in a variety of carbonate reservoirs in the Rocky Mountain region of the US. These studies provide insights into a wide range of geologic environments, including natural CO2 reservoirs, geologic carbon sequestration, engineered geothermal systems, enhanced oil and gas recovery, and unconventional hydrocarbon resources. One suite of experiments evaluates the Madison Limestone on the Moxa Arch, Southwest Wyoming, a sulfur-rich natural CO2 reservoir. Mineral textures and geochemical features developed in the experiments suggest that carbonate minerals which constitute the natural reservoir will initially dissolve in response to emplacement of CO2. Euhedral, bladed anhydrite concomitantly precipitates in response to injected CO2. Analogous anhydrite is observed in drill core, suggesting that secondary anhydrite in the natural reservoir may be related to emplacement of CO2 into the Madison Limestone. Carbonate minerals ultimately re-precipitate, and anhydrite dissolves, as the rock buffers the acidity and reasserts geochemical control. Another suite of experiments emulates injection of CO2 for enhanced oil recovery in the Desert Creek Limestone (Paradox Formation), Paradox Basin, Southeast Utah. Euhedral iron oxyhydroxides (hematite) precipitate at pH 4.5 to 5 and low Eh (approximately -0.1 V) as a consequence of water-rock reaction. Injection of CO2 decreases pH to approximately 3.5 and increases Eh by approximately 0.1 V, yielding secondary mineralization of euhedral pyrite instead of iron oxyhydroxides. Carbonate minerals also dissolve and ultimately re-precipitate, as determined by experiments in the

  9. A GIS method for assessment of rock slide tsunami hazard in all Norwegian lakes and reservoirs

    Directory of Open Access Journals (Sweden)

    B. Romstad

    2009-03-01

    Full Text Available An evaluation of rock slide tsunami hazard is applied to all Norwegian lakes larger than 0.1 km2 based on their topographical setting. The analysis results in a topographic rock slide potential score that indicates the relative hazard in each lake. Even though the score value each lake receives should be interpreted with caution, the distribution of score values shows that we are able to make a clear distinction between lakes with a high vs. lakes with a low hazard. The results also show a clustering of threatened lakes in parts of Western Norway as well as some locations in Northern Norway. This makes the results useful as a tool for focusing further studies on regions or specific lakes that received high scores. The results also show how the method may be used for more detailed analysis of a given lake (or fjord. Maps can be produced that may serve as a guide when carrying out field campaigns or when designing scenarios for numerical simulations of tsunamis in the lake. It should be emphasised that the rock slide potential reported for each lake is based on the topographical setting alone and hence, does not represent the actual probability of rock slides into the lakes. For a given area, more detailed investigations of the geology, triggering factors and frequency of previous rock slide events should be carried out before definite statements about the actual hazard can be made.

  10. Experimental study on pore pressure in rock-soil slope during reservoir water level fluctuation

    Institute of Scientific and Technical Information of China (English)

    LIU; Yuewu; CHEN; Huixin; LIU; Qingquan; GONG; Xin; ZHANG

    2005-01-01

    A test system was developed for measuring the pore pressure in porous media, and a new model was devised for the pore pressure testing in both saturated and unsaturated rock-soil. Laboratory experiments were carried out to determine the pore pressure during water level fluctuation. The variations of transient pore pressure vs. time at different locations of the simulated rock-soil system were acquired and processed, and meanwhile the deformation and failure of the model are observed. The experiment results show that whether the porous media are saturated or not, the transient pore pressure is mainly dependent on the water level fluctuation, and coupled with the variation of the stress field.

  11. Hydraulic properties of siliciclastic geothermal reservoir rocks under triaxial stress conditions, a multidisciplinary approach.

    Science.gov (United States)

    Bakker, Richard; Gholizadeh Doonechaly, Nima; Bruhn, David

    2017-04-01

    Cretaceous Sandstone bodies in the subsurface of western Netherlands are already used for heating some of the greenhouses in that area. The reservoirs used are typically at depths between 1500 and 3000m, with temperatures generally conditions of failure. Secondly, the experiment is repeated using relatively strong jackets which remain sealing after sample failure, allowing for permeability measurements. Preliminary results show that an increase of confining pressure leads to a decrease of permeability by three orders of magnitude, from 1e-13 to 1e-16 m2. Anisotropy results in permeability parallel to bedding to be roughly one order of magnitude higher than perpendicular to it. Based on the collected data, the validity of the available exponential permeability-porosity-stress relationship is assessed and the model parameters with the best fitting characteristic is chosen for the selected formation. The established relationship is then used as an input for field scale numerical simulation of cold fluid circulation in Buntsandstein formation to predict the reservoir behavior over longer term of fluid circulation. The Finite Element Method is used to evaluate the reservoir behaviour during injection/production of the cold/hot fluid in a fully coupled poro-thermo-elastic environment. Weighted residual method is used for deriving the weak formulation of the mass-, momentum- and energy balance equations. Consequently the standard Galerkin approach is used for spatial discretization of the weak formulas. Temporal discretization is also carried out in a fully implicit manner to avoid the time-stepping limitation. The preliminary results of this study show a promising capacity of heat extraction from the Buntsandstein formation as a geothermal reservoir within western Netherlands.

  12. Combined rock-physical modelling and seismic inversion techniques for characterisation of stacked sandstone reservoir

    NARCIS (Netherlands)

    Justiniano, A.; Jaya, Y.; Diephuis, G.; Veenhof, R.; Pringle, T.

    2015-01-01

    The objective of the study is to characterise the Triassic massive stacked sandstone deposits of the Main Buntsandstein Subgroup at Block Q16 located in the West Netherlands Basin. The characterisation was carried out through combining rock-physics modelling and seismic inversion techniques. The app

  13. Combined rock-physical modelling and seismic inversion techniques for characterisation of stacked sandstone reservoir

    NARCIS (Netherlands)

    Justiniano, A.; Jaya, Y.; Diephuis, G.; Veenhof, R.; Pringle, T.

    2015-01-01

    The objective of the study is to characterise the Triassic massive stacked sandstone deposits of the Main Buntsandstein Subgroup at Block Q16 located in the West Netherlands Basin. The characterisation was carried out through combining rock-physics modelling and seismic inversion techniques. The app

  14. Reconstruction of rocks petrophysical properties as input data for reservoir modeling

    Science.gov (United States)

    Cantucci, B.; Montegrossi, G.; Lucci, F.; Quattrocchi, F.

    2016-11-01

    The worldwide increasing energy demand triggered studies focused on defining the underground energy potential even in areas previously discharged or neglected. Nowadays, geological gas storage (CO2 and/or CH4) and geothermal energy are considered strategic for low-carbon energy development. A widespread and safe application of these technologies needs an accurate characterization of the underground, in terms of geology, hydrogeology, geochemistry, and geomechanics. However, during prefeasibility study-stage, the limited number of available direct measurements of reservoirs, and the high costs of reopening closed deep wells must be taken into account. The aim of this work is to overcome these limits, proposing a new methodology to reconstruct vertical profiles, from surface to reservoir base, of: (i) thermal capacity, (ii) thermal conductivity, (iii) porosity, and (iv) permeability, through integration of well-log information, petrographic observations on inland outcropping samples, and flow and heat transport modeling. As case study to test our procedure we selected a deep structure, located in the medium Tyrrhenian Sea (Italy). Obtained results are consistent with measured data, confirming the validity of the proposed model. Notwithstanding intrinsic limitations due to manual calibration of the model with measured data, this methodology represents an useful tool for reservoir and geochemical modelers that need to define petrophysical input data for underground modeling before the well reopening.

  15. How the rock fabrics can control the physical properties - A contribution to the understanding of carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Duerrast, H.; Siegesmund, S. [Goettingen Univ. (Germany)

    1998-12-31

    The correlation between microfabrics and physical properties will be illustrated in detail on three dolomitic carbonate reservoir rocks with different porosity. For this study core segments from the Zechstein Ca2-layer (Permian) of the Northwest German Basin were kindly provided by the Preussag Energie GmbH, Lingen. The mineral composition was determined by using the X-ray diffraction method. Petrographic and detailed investigation of the microfabrics, including the distribution and orientation of the cracks were done macroscopally (core segments) and microscopally with the optical microscope and the Scanning Electron Microscope (thin sections in three orthogonally to each other oriented directions). Different kinds of petrophysical measurements were carried out, e.g. porosity, permeability, electrical conductivity, seismic velocities. (orig.)

  16. Discovery and its geological significance of the mantle-derived helium in the inclusions of the Ordovician oil-bearing reservoir rocks in the Huanghua depression, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaobao; XU Yongchang; SUN Mingliang; CHENG Keming; LIU Wenhui; LI Xiufen; MA Liyuan

    2004-01-01

    The values of the helium isotopes in the inclusions of the Ordovician reservoir rocks in the Kongxi buried hill belt in the Huanghua depression were first measured and the source of helium and its geological significance were investigated in comparison with those of the helium isotopes in the conclusions in the Ordovician rocks in the Ordos basin and the Tarim basin. The input of the mantle-derived helium into the inclusions in the carbonate reservoir rocks was found from the Konggu 3 well, the Konggu 4 well, and the Konggu 7 well in the Kongxi buried hill belt. The 3He/4He and R/Ra in the conclusions in the Ordovician oil-bearing reservoir rocks in the Konggu 7 well average 2.54×10-6(3) (sample quantity, the same below) and 1.82(3), respectively. The percent of the mantle-derived helium in the inclusions of the reservoir rocks in the Konggu 7 well reaches up to an average of 23.0%(3). The age of the contribution of the mantle-derived helium to the inclusions in the Kongxi buried hill belt is in the Late Triassic or the Early Tertiary. The finding of the mantle-derived helium shows that the interaction of the deep crust with mantle and the activity of deep faults occurred, the terrestrial heat flow value was high, and mantle-derived inorganic gas pools might be formed in the Kongxi buried hill belt. The finding of the mantle-derived helium in the inclusions of oil-bearing reservoir rocks also provides a new way for researching the activity of mantle-derived matter and its associated geological problems.

  17. Fracture-related fluid migration and fluid-rock interaction in outcrop analogues of Buntsandstein reservoir rocks (southern Thuringia and northern Hesse)

    Science.gov (United States)

    Kasch, Norbert; Kley, Jonas; Köster, Jens; Wendler, Jens

    2010-05-01

    Suitable reservoir rocks for carbon capture and storage (CCS) in saline aquifers must be porous, permeable and reside at depths below c. 800 m in structurally simple, preferrably unfaulted settings. In central Europe, the Lower and particularly Middle Buntsandstein are regionally extensive stratigraphic units which often meet these requirements. While often deeply buried, the Buntsandstein is exposed at the surface and easily accessible in other areas. We have studied the evidence for natural fluid flux in Buntsandstein reservoir outcrop analogues and drill cores of southern Thuringia and northern Hesse. The clearest sign of fluid-rock interaction is local bleaching of the red sandstones. In the field and on drill cores we did not observe bleaching along faults, but commonly along joints. There, the bleached fringes may have sharp or diffuse boundaries and can be traced along individual joints for a few dm to m. They are most often observed on small joints and fine cracks. Using 3D laser scanning, photostereogrammetry and manual measurements we established the geometric properties of the joint systems. The joint systems always comprise several joint sets, but in southern Thuringia bleaching is restricted to one north-trending set. Mining reports and geological maps show that basalt dikes of Tertiary age in this region also trend north. In the underground salt mines of the Werra potassium district, potassium salt minerals show bleaching at the contacts with the dikes. Also, CO2 is found trapped within rock salt along north-trending fractures, sometimes causing violent gas eruptions during mining operations. Taken together, these observations suggest that the bleaching along north-trending joints in the Buntsandstein is causally related to the migration of CO2-bearing fluids associated with the basalt volcanism. However, the Fe-releasing process may depend on admixtures of other phases, most likely hydrocarbons released from bituminous Zechstein carbonates

  18. Factors affecting storage of compressed air in porous-rock reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Doherty, T.J.; Erikson, R.L.; Wiles, L.E.

    1983-05-01

    This report documents a review and evaluation of the geotechnical aspects of porous medium (aquifer) storage. These aspects include geologic, petrologic, geophysical, hydrologic, and geochemical characteristics of porous rock masses and their interactions with compressed air energy storage (CAES) operations. The primary objective is to present criteria categories for the design and stability of CAES in porous media (aquifers). The document will also describe analytical, laboratory, and field-scale investigations that have been conducted.

  19. Elastic wave velocities and Poisson`s ratio in reservoir rocks; Choryugan no danseiha sokudo to Poisson hi

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Y. [Japan National Oil Corp., Tokyo (Japan)

    1998-04-01

    This paper discusses the relationship between elastic wave velocities and physical properties of reservoir rocks. For sandstones, the elastic wave velocity decreases with increasing the porosity and the content of clay minerals. For rocks containing heavy oil, the P-wave velocity decreases with increasing the temperature. The P-wave velocity under dry condition is much more lower than that under water saturated condition. When there are a few percent of gas in pores against the water saturated condition, the P-wave velocity decreases rapidly. It is almost constant under the lower water saturation factor. The S-wave velocity is almost constant independent of the water saturation factor. Accordingly, the water saturation factor can not be estimated from the elastic wave velocity at the water saturation factor between 0% and 96%. The Poisson`s ratio also greatly decreases at the water saturation factor between 96% and 100%, but it is almost constant under the lower water saturation factor. The elastic wave velocity increases with increasing the pressure or increasing the depth. Since closure of cracks by pressure is inhibited due to high pore pressure, degree of increase in the elastic wave velocity is reduced. 14 refs., 6 figs.

  20. Numerical simulation of ultrasonic wave transmission experiments in rocks of shale gas reservoirs

    Science.gov (United States)

    Chen, Qiao; Yao, Guanghua; Zhu, Honglin; Tan, Yanhu; Xu, Fenglin

    2017-01-01

    Shale gas reservoirs have risen in importance in China's new power source exploration and development program. The investigation of the propagation of ultrasonic waves in shale forms the basis for the full waveform application of acoustic logging data to the exploration of shale gas. Using acoustic wave theory, initial conditions, vibration source conditions, and stability conditions are developed in combination with experimental background of ultrasonic wave transmission. With improved boundary conditions, we performed numerical simulations of the ultrasound transmission experiments in shale using the high-order staggered-grid finite difference method (second-order in the time domain and fourth-order in the space domain). With programs developed within MatLab, the results obtained from numerical simulations agree well with experimental results based on physical models. In addition, using snapshots of the wave field that give a microscopic perspective, the propagation laws for ultrasonic waves can be analyzed. Using this method, human error is avoided, transmission experiments costs can be reduced and efficiency improved. This method extends the scope of experimental investigations regarding the transmission of ultrasonic waves in a shale gas reservoir with increasing stratification, and thus has great theoretical value and practical significance.

  1. Drag reduction in reservoir rock surface: Hydrophobic modification by SiO2 nanofluids

    Science.gov (United States)

    Yan, Yong-Li; Cui, Ming-Yue; Jiang, Wei-Dong; He, An-Le; Liang, Chong

    2017-02-01

    Based on the adsorption behavior of modified silica nanoparticles in the sandstone core surface, the hydrophobic surface was constructed, which consists of micro-nanoscale hierarchical structure. This modified core surface presents a property of drag reduction and meets the challenge of high injection pressure and low injection rate in low or ultra-low permeability reservoir. The modification effects on the surface of silica nanoparticles and reservoir cores, mainly concerning hydrophobicity and fine structure, were determined by measurements of contact angle and scanning electron microscopy. Experimental results indicate that after successful modification, the contact angle of silica nanoparticles varies from 19.5° to 141.7°, exhibiting remarkable hydrophobic properties. These modified hydrophobic silica nanoparticles display a good adsorption behavior at the core surface to form micro-nanobinary structure. As for the wettability of these modified core surfaces, a reversal has happened from hydrophilic into hydrophobic and its contact angle increases from 59.1° to 105.9°. The core displacement experiments show that the relative permeability for water has significantly increased by an average of 40.3% via core surface modification, with the effects of reducing injection pressure and improving injection performance of water flooding. Meanwhile, the mechanisms of drag reduction and improving water injection operation induced from the modified core surface were uncovered. The present study will establish a fundamental understanding on the drag reduction at the core surface modified by nanofluids and its applications in more industries.

  2. Numerical simulation of ultrasonic wave transmission experiments in rocks of shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Qiao Chen

    2017-01-01

    Full Text Available Shale gas reservoirs have risen in importance in China’s new power source exploration and development program. The investigation of the propagation of ultrasonic waves in shale forms the basis for the full waveform application of acoustic logging data to the exploration of shale gas. Using acoustic wave theory, initial conditions, vibration source conditions, and stability conditions are developed in combination with experimental background of ultrasonic wave transmission. With improved boundary conditions, we performed numerical simulations of the ultrasound transmission experiments in shale using the high-order staggered-grid finite difference method (second-order in the time domain and fourth-order in the space domain. With programs developed within MatLab, the results obtained from numerical simulations agree well with experimental results based on physical models. In addition, using snapshots of the wave field that give a microscopic perspective, the propagation laws for ultrasonic waves can be analyzed. Using this method, human error is avoided, transmission experiments costs can be reduced and efficiency improved. This method extends the scope of experimental investigations regarding the transmission of ultrasonic waves in a shale gas reservoir with increasing stratification, and thus has great theoretical value and practical significance.

  3. Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Ba Nghiep; Hou, Zhangshuan; Bacon, Diana H.; Murray, Christopher J.; White, Mark D.

    2016-01-04

    This article develops a novel multiscale modeling approach to analyze CO2 reservoirs using Pacific Northwest National Laboratory’s STOMP-CO2-R code that is interfaced with the ABAQUS® finite element package. The STOMP-CO2-R/ABAQUS® sequentially coupled simulator accounts for the reactive transport of CO2 causing mineral composition changes that modify the geomechanical properties of reservoir rocks and seals. Formation rocks’ elastic properties that vary during CO2 injection and govern the poroelastic behavior of rocks are modeled by an Eshelby-Mori-Tanka approach (EMTA) implemented in ABAQUS® via user-subroutines. The computational tool incorporates the change in rock permeability due to both geochemistry and geomechanics. A three-dimensional (3D) STOMP-CO2-R model for a model CO2 reservoir containing a vertical fault is built to analyze a formation containing a realistic geochemical reaction network with 5 minerals: albite, anorthite, calcite, kaolinite and quartz. A 3D ABAQUS® model that maps the above STOMP-CO2-R model is built for the analysis using STOMP-CO2-R/ABAQUS®. The results show that the changes in volume fraction of minerals include dissolution of anorthite, precipitation of calcite and kaolinite, with little change in the albite volume fraction. After a long period of CO2 injection the mineralogical and geomechanical changes significantly reduced the permeability and elastic modulus of the reservoir (between the base and caprock) in front of the fault leading to a reduction of the pressure margin to fracture at and beyond the injection location. The impact of reactive transport of CO2 on the geomechanical properties of reservoir rocks and seals are studied in terms of mineral composition changes that directly affect the rock stiffness, stress and strain distributions as well as the pressure margin to fracture.

  4. Characterization of reservoir rocks and fluids by surface electromagnetic transient methods

    Energy Technology Data Exchange (ETDEWEB)

    Hoekstra, P.; Blohm, M.W. (Blackhawk Geosciences, Inc., Golden, CO (United States)); Stoyer, C.H. (Interpex Ltd. (United States)); James, B.A. (James Consulting Services (United States))

    1992-01-01

    The objectives of this research are to improve the interpretations of transient electromagnetic (TEM) measurements over two-dimensional subsurface structures. TEM is a surface electromagnetic method employed in fossil energy reservoir exploration and characterization. Electrical measurements find application in (i) assisting in fossil energy exploration mainly in areas where seismic methods yield inadequate data quality, such as volcanic covered terrain, permafrost areas, and the Rocky Mountain overthrust; (ii) mapping contacts between hydrocarbon and brines in shallow producing horizons, and (iii) in monitoring enhanced oil recovery processes which cause zones of lower resistivity. Accomplishments for this past year are presented for the following tasks: (1) site selection and acquisition of high density, 3-component TEM data set over test site; (2) finite element forward modeling; and (3) TEM 2-D subsurface imaging.

  5. The Baltic Basin: structure, properties of reservoir rocks, and capacity for geological storage of CO2

    Directory of Open Access Journals (Sweden)

    Vaher, Rein

    2009-12-01

    Full Text Available Baltic countries are located in the limits of the Baltic sedimentary basin, a 700 km long and 500 km wide synclinal structure. The axis of the syneclise plunges to the southwest. In Poland the Precambrian basement occurs at a depth of 5 km. The Baltic Basin includes the Neoproterozoic Ediacaran (Vendian at the base and all Phanerozoic systems. Two aquifers, the lower Devonian and Cambrian reservoirs, meet the basic requirements for CO2 storage. The porosity and permeability of sandstone decrease with depth. The average porosity of Cambrian sandstone at depths of 80–800, 800–1800, and 1800–2300 m is 18.6, 14.2, and 5.5%, respectively. The average permeability is, respectively, 311, 251, and 12 mD. Devonian sandstone has an average porosity of 26% and permeability in the range of 0.5–2 D. Prospective Cambrian structural traps occur only in Latvia. The 16 largest ones have CO2 storage capacity in the range of 2–74 Mt, with total capacity exceeding 400 Mt. The structural trapping is not an option for Lithuania as the uplifts there are too small. Another option is utilization of CO2 for enhanced oil recovery (EOR. The estimated total EOR net volume of CO2 (part of CO2 remaining in the formation in Lithuania is 5.6 Mt. Solubility and mineral trapping are a long-term option. The calculated total solubility trapping capacity of the Cambrian reservoir is as high as 11 Gt of CO2 within the area of the supercritical state of carbon dioxide.

  6. Special core analyses and relative permeability measurement on Almond formation reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, D.; Doggett, K.; Brinkmeyer, A.

    1993-02-01

    This report describes the results from special core analyses and relative permeability measurements conducted on samples of rock from the Almond Formation in Greater Green River Basin of southwestern Wyoming. The core was from Arch Unit Well 121 of Patrick Draw field. Samples were taken from the 4,950 to 4,965 ft depth interval. Thin section evaluation, X-ray diffraction, routine permeability and porosity, capillary pressure and wettability tests were performed to characterize the samples. Fluid flow capacity characteristics were measured during two-phase unsteady- and steady-state and three-phase steady-state relative permeability tests. Test results are presented in tables and graphs. Relative permeability results are compared with those of a 260-mD, fired Berea sandstone sample which was previously subjected to similar tests. Brine relative permeabilities were similar for the two samples, whereas oil and gas relative permeabilities for the Almond formation rock were higher at equivalent saturation conditions compared to Berea results. Most of the tests described in this report were conducted at 74{degrees}F laboratory temperature. Additional tests are planned at 150{degrees}F temperature. Equipment and procedural modifications to perform the elevated temperature tests are described.

  7. Special core analyses and relative permeability measurement on Almond formation reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, D.; Doggett, K.; Brinkmeyer, A.

    1993-02-01

    This report describes the results from special core analyses and relative permeability measurements conducted on samples of rock from the Almond Formation in Greater Green River Basin of southwestern Wyoming. The core was from Arch Unit Well 121 of Patrick Draw field. Samples were taken from the 4,950 to 4,965 ft depth interval. Thin section evaluation, X-ray diffraction, routine permeability and porosity, capillary pressure and wettability tests were performed to characterize the samples. Fluid flow capacity characteristics were measured during two-phase unsteady- and steady-state and three-phase steady-state relative permeability tests. Test results are presented in tables and graphs. Relative permeability results are compared with those of a 260-mD, fired Berea sandstone sample which was previously subjected to similar tests. Brine relative permeabilities were similar for the two samples, whereas oil and gas relative permeabilities for the Almond formation rock were higher at equivalent saturation conditions compared to Berea results. Most of the tests described in this report were conducted at 74[degrees]F laboratory temperature. Additional tests are planned at 150[degrees]F temperature. Equipment and procedural modifications to perform the elevated temperature tests are described.

  8. Final Report: Development of a Chemical Model to Predict the Interactions between Supercritical CO2, Fluid and Rock in EGS Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, Brian J. [University of Utah; Pan, Feng [University of Utah

    2014-09-24

    This report summarizes development of a coupled-process reservoir model for simulating enhanced geothermal systems (EGS) that utilize supercritical carbon dioxide as a working fluid. Specifically, the project team developed an advanced chemical kinetic model for evaluating important processes in EGS reservoirs, such as mineral precipitation and dissolution at elevated temperature and pressure, and for evaluating potential impacts on EGS surface facilities by related chemical processes. We assembled a new database for better-calibrated simulation of water/brine/ rock/CO2 interactions in EGS reservoirs. This database utilizes existing kinetic and other chemical data, and we updated those data to reflect corrections for elevated temperature and pressure conditions of EGS reservoirs.

  9. Using three-dimensional reconstructed microstructures for predicting intrinsic permeability of reservoir rocks based on a Boolean lattice gas method

    Energy Technology Data Exchange (ETDEWEB)

    Santos, L.O.E.; Philippi, P.C.; Fernandes, C.P. [Porous Media and Thermophysical Properties Laboratory LMPT, Mechanical Engineering Department, Federal University of Santa Catarina, 88040-900 , SC Florianopolis (Brazil); Damiani, M.C. [Engineering Simulation and Scientific Software ESSS, Parque Tecnologico de Florianopolis, Rodovia SC 401 km 001, 88030-000 , SC Florianopolis (Brazil)

    2002-07-01

    This paper presents a method for predicting the intrinsic permeability of porous media based on the integration of the local velocity field. Three-dimensional representations of the porous structure are reconstructed from two-dimensional binary images, after segmentation of digital images acquired from thin plates, commonly used in microscopy. Velocity field is calculated on these three-dimensional representations using a Boolean lattice gas method (LGA). Reconstruction is based on a Gaussian stochastic simulation. Mercury-intrusion results furnish auxiliary data that are used for the estimation of a critical percolation diameter and to establish a necessary condition for the binary source images to give accurate predictions of permeability, considering the intrinsic limitations of the reconstruction process. Reconstruction method and connection loss, resolution factor, adherence conditions and the effects of Boolean noise in the calculation of permeability are fully discussed. The method is used to simulate flows through several petroleum reservoir rocks, leading to intrinsic permeability prediction. Simulation is compared with experimental results. Considered as an intrinsic permeability prediction method based on the geometrical information that is possible to recovery from microscopy thin plates, three-dimensional reconstruction appears to be the most critical step in present simulation scheme.

  10. Fracture system influence on the reservoirs rock formation of Ordovician-Devonian carbonates in West Siberia tectonic depression

    Science.gov (United States)

    Koveshnikov, A. E.; Nesterova, A. C.; Dolgaya, T. F.

    2016-09-01

    During the Paleozoic period from the beginning of the Cambrian to the end of the Carboniferous in the boundaries of the West Siberia tectonic depression there occurred the sea, where the carbonate platforms were formed by the limestones accumulation. All the area at the end of the Carboniferous period was turned to land. Resulting from Gertsynskaya folding in the times of Permian - Triassic the formed deposits were folded and denudated to a considerable extent. Besides, the reservoir rocks of the crust of weathering including redeposited one, were formed as a result of hypergenesis, during the continental stand of the area in the near-surface zone. A new geological prospecting unit has been suggested which underlies these crusts of weathering and formed during fracture tectonic processes with hydrothermal-metasomatic limestones reworking and the processes of hydrothermal leaching and dolomitization. So, in the carbonate platforms the system of fissure zones related to tectonic disturbance was formed. This has a dendrite profile where the series of tangential, more thinned fractures deviate from the stem and finish in pores and caverns. The carbonate platforms formation in the West Siberia tectonic depression has been analyzed, their dynamics and gradual increasing from the minimal in Ordovician and Silurian to maximal at the end of the Late Devonian has been shown.

  11. ADVANCED CHARACTERIZATION OF FRACTURED RESERVOIRS IN CARBONATE ROCKS: THE MICHIGAN BASIN

    Energy Technology Data Exchange (ETDEWEB)

    James R. Wood; William B. Harrison

    2001-04-01

    Among the accomplishments of this past reporting period are obtaining a complete landgrid for the State of Michigan and the digital processing of the high and medium resolution DEM files. We can now extract lineations from the DEMs automatically using machine algorithms. One tentative result that may be very significant is that we may be seeing manifestations of buried structures in the DEM data. We are looking at a set of extracted lineations in the northern lower peninsula that appear to follow the trend of the pinnacle reefs (Silurian) which had relief approaching 300 feet but are now buried to greater than 3000 feet. We have also extracted the dolomite alteration data from all fields and can show that this is mainly confined to the basin center. It may be related to the paleo-rift suggested by the paleomagnetic and gravity data. As reported last time, the acquisition of a 3D seismic dataset over Stoney Point Field from Marathon Oil Company, is complete and attention is being devoted to incorporating the data into the project database and utilizing it. The surface lineation study is focusing on Stoney Point Field using the high-resolution DEM data and plotting of subsurface formation top data for the main reservoir, the Trenton (Ordovician) Formation. The fault pattern at Stoney Point is well documented by Marathon and we are looking for any manifestations on the surface. The main project database is now about as complete as it will be for this project. The main goals have been met, although the scanning of the paper records will have to continue beyond the scheduled end of the project due to the sheer number of records and the increased donations of data from companies as word spread of the project. One of the unanticipated benefits of the project has been the cooperation of gas and oil companies that are or were active in the Michigan Basin in donating material to the project. Both Michigan Tech and Western Michigan continue to receive donations at an

  12. Origin and evolution of formation water at the Jujo-Tecominoacan oil reservoir, Gulf of Mexico. Part 1: Chemical evolution and water-rock interaction

    Energy Technology Data Exchange (ETDEWEB)

    Birkle, Peter, E-mail: birkle@iie.org.mx [Instituto de Investigaciones Electricas (IIE), Gerencia de Geotermia, Av. Reforma 113, Cuernavaca, Morelos 62490 (Mexico); Garcia, Bernardo Martinez; Milland Padron, Carlos M. [PEMEX Exploracion y Produccion, Region Sur, Activo Integral Bellota-Jujo, Diseno de Explotacion, Cardenas, Tabasco (Mexico)

    2009-04-15

    The origin and evolution of formation water from Upper Jurassic to Upper Cretaceous mudstone-packstone-dolomite host rocks at the Jujo-Tecominoacan oil reservoir, located onshore in SE-Mexico at a depth from 5200 to 6200 m.b.s.l., have been investigated, using detailed water geochemistry from 12 producer wells and six closed wells, and related host rock mineralogy. Saline waters of Cl-Na type with total dissolved solids from 10 to 23 g/L are chemically distinct from hypersaline Cl-Ca-Na and Cl-Na-Ca type waters with TDS between 181 and 385 g/L. Bromine/Cl and Br/Na ratios suggest the subaerial evaporation of seawater beyond halite precipitation to explain the extreme hypersaline components, while less saline samples were formed by mixing of high salinity end members with surface-derived, low salinity water components. The dissolution of evaporites from adjacent salt domes has little impact on present formation water composition. Geochemical simulations with Harvie-M{phi}ller-Weare and PHRQPITZ thermodynamic data sets suggest secondary fluid enrichment in Ca, HCO{sub 3} and Sr by water-rock interaction. The volumetric mass balance between Ca enrichment and Mg depletion confirms dolomitization as the major alteration process. Potassium/Cl ratios below evaporation trajectory are attributed to minor precipitation of K feldspar and illitization without evidence for albitization at the Jujo-Tecominoacan reservoir. The abundance of secondary dolomite, illite and pyrite in drilling cores from reservoir host rock reconfirms the observed water-rock exchange processes. Sulfate concentrations are controlled by anhydrite solubility as indicated by positive SI-values, although anhydrite deposition is limited throughout the lithological reservoir column. The chemical variety of produced water at the Jujo-Tecominoacan oil field is related to a sequence of primary and secondary processes, including infiltration of evaporated seawater and original meteoric fluids, the subsequent

  13. Sequence stratigraphic features of the Middle Permian Maokou Formation in the Sichuan Basin and their controls on source rocks and reservoirs

    Directory of Open Access Journals (Sweden)

    Wang Su

    2015-11-01

    Full Text Available Well Shuangyushi 1 and Well Nanchong l deployed in the NW and central Sichuan Basin have obtained a high-yield industrial gas flow in the dolomite and karst reservoirs of the Middle Permian Maokou Formation, showing good exploration prospects of the Maokou Formation. In order to identify the sequence stratigraphic features of the Maokou Formation, its sequence stratigraphy was divided and a unified sequence stratigraphic framework applicable for the entire basin was established to analyze the stratigraphic denudation features within the sequence framework by using the spectral curve trend attribute analysis, together with drilling and outcrop data. On this basis, the controls of sequence on source rocks and reservoirs were analyzed. In particular, the Maokou Formation was divided into two third-order sequences – SQ1 and SQ2. SQ1 was composed of members Mao 1 Member and Mao 3, while SQ2 was composed of Mao 4 Member. Sequence stratigraphic correlation indicated that the Maokou Formation within the basin had experienced erosion to varying extent, forming “three intense and two weak” denuded regions, among which, the upper part of SQ2 was slightly denuded in the two weak denuded regions (SW Sichuan Basin and locally Eastern Sichuan Basin, while SQ2 was denuded out in the three intense denuded regions (Southern Sichuan Basin–Central Sichuan Basin, NE and NW Sichuan Basin. The development of source rocks and reservoirs within sequence stratigraphic framework was significantly affected by sequence boundary; the grain banks that can form effective reservoir were predominately distributed in SQ1 highstand systems tract (HST, while effective source rocks were predominately distributed in SQ1 transgressive system tract (TST. It is concluded that the sequence division method is objective and reasonable, which can effectively guide oil and gas exploration in this region.

  14. Petrophysical examination of CO₂-brine-rock interactions-results of the first stage of long-term experiments in the potential Zaosie Anticline reservoir (central Poland) for CO₂ storage.

    Science.gov (United States)

    Tarkowski, Radosław; Wdowin, Magdalena; Manecki, Maciej

    2015-01-01

    The objective of the study was determination of experiment-induced alterations and changes in the properties of reservoir rocks and sealing rocks sampled from potential reservoir for CO₂. In the experiment, rocks submerged in brine in specially constructed reactors were subjected to CO₂ pressure of 6 MPa for 20 months at room temperature. Samples of Lower Jurassic reservoir rocks and sealing rocks (sandstones, claystones, and mudstones) from the Zaosie Anticline (central Poland) were analysed for their petrophysical properties (specific surface area, porosity, pore size and distribution) before and after the experiment. Comparison of the ionic composition the brines before and after the experiment demonstrated an increase in total dissolved solids as well as the concentration of sulphates and calcium ions. This indicates partial dissolution of the rock matrix and the cements. As a result of the reaction, the properties of reservoir rocks did not changed significantly and should not affect the process of CO₂ storage. In the case of the sealing rocks, however, the porosity, the framework density, as well as the average capillary and threshold diameter increased. Also, the pore distribution in the pore space changed in favour of larger pores. The reasons for these changes could not be explained by petrographic characteristics and should be thoroughly investigated.

  15. Real-time detection of dielectric anisotropy or isotropy in unconventional oil-gas reservoir rocks supported by the oblique-incidence reflectivity difference technique

    Science.gov (United States)

    Zhan, Honglei; Wang, Jin; Zhao, Kun; Lű, Huibin; Jin, Kuijuan; He, Liping; Yang, Guozhen; Xiao, Lizhi

    2016-12-01

    Current geological extraction theory and techniques are very limited to adequately characterize the unconventional oil-gas reservoirs because of the considerable complexity of the geological structures. Optical measurement has the advantages of non-interference with the earth magnetic fields, and is often useful in detecting various physical properties. One key parameter that can be detected using optical methods is the dielectric permittivity, which reflects the mineral and organic properties. Here we reported an oblique-incidence reflectivity difference (OIRD) technique that is sensitive to the dielectric and surface properties and can be applied to characterization of reservoir rocks, such as shale and sandstone core samples extracted from subsurface. The layered distribution of the dielectric properties in shales and the uniform distribution in sandstones are clearly identified using the OIRD signals. In shales, the micro-cracks and particle orientation result in directional changes of the dielectric and surface properties, and thus, the isotropy and anisotropy of the rock can be characterized by OIRD. As the dielectric and surface properties are closely related to the hydrocarbon-bearing features in oil-gas reservoirs, we believe that the precise measurement carried with OIRD can help in improving the recovery efficiency in well-drilling process.

  16. Real-time detection of dielectric anisotropy or isotropy in unconventional oil-gas reservoir rocks supported by the oblique-incidence reflectivity difference technique

    Science.gov (United States)

    Zhan, Honglei; Wang, Jin; Zhao, Kun; Lű, Huibin; Jin, Kuijuan; He, Liping; Yang, Guozhen; Xiao, Lizhi

    2016-01-01

    Current geological extraction theory and techniques are very limited to adequately characterize the unconventional oil-gas reservoirs because of the considerable complexity of the geological structures. Optical measurement has the advantages of non-interference with the earth magnetic fields, and is often useful in detecting various physical properties. One key parameter that can be detected using optical methods is the dielectric permittivity, which reflects the mineral and organic properties. Here we reported an oblique-incidence reflectivity difference (OIRD) technique that is sensitive to the dielectric and surface properties and can be applied to characterization of reservoir rocks, such as shale and sandstone core samples extracted from subsurface. The layered distribution of the dielectric properties in shales and the uniform distribution in sandstones are clearly identified using the OIRD signals. In shales, the micro-cracks and particle orientation result in directional changes of the dielectric and surface properties, and thus, the isotropy and anisotropy of the rock can be characterized by OIRD. As the dielectric and surface properties are closely related to the hydrocarbon-bearing features in oil-gas reservoirs, we believe that the precise measurement carried with OIRD can help in improving the recovery efficiency in well-drilling process. PMID:27976746

  17. Permeability evaluation of reservoir rocks modeled in multi scale percolation systems; Determinacao da permeabilidade de rochas reservatorio reconstruidas em sistemas de percolacao multiescala

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Celso P.; Philippi, Paulo C.; Damiani, Marcos C.; Cunha Neto, Jose A.B. da [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica. Lab. de Meios Porosos e Propriedades Termofisicas]. E-mail: celso@lmpt.ufsc.br; philippi@lmpt.ufsc.br; damiani@lmpt.ufsc.br; bellini@lmpt.ufsc.br; Daian, Jean-Francois (Laboratoire d' Etudes des Transferts en Hydrologie et Environement)

    2000-07-01

    Multiscale percolation systems (MPS) are presented as giving a fast method for calculating intrinsic permeability of porous media. MPS were proposed to study invasion processes in porous media considering the porous section as a polydisperse structure, which modify its geometrical structure when the scale of observation is changed. Multiscale models are non-regular percolation systems and do not have the following limitations common to classical percolation systems: it is not necessary to choose a particular value for the coordination number; constrictions appears naturally as pores of smaller diameters connecting pores of greater diameters, as the result of superposing different scales (Fernandes, C. P., Magnani, F.S., Philippi, P.C., Daian, J.F. 1996, Multiscale reconstruction of the porous structure, Physical Review E, 54, 1734-1742). Present paper describes the numerical prediction of intrinsic permeability of petroleum reservoir rocks by using a MPS approach. Rock's microstructure is reconstructed in a three dimensional MPS, starting from 2D thin sections geometrical information, after binarization and microstructural analysis. Intrinsic permeability is, then, calculated, using a procedure based on renormalization theory. The method is presented and applied for the calculation of intrinsic permeability of several petroleum reservoir rocks. Results are compared with experimental data. (author)

  18. Certain features in the lithogenesis and formation of rock-reservoirs of Devonian Age in the Pripyat trough

    Energy Technology Data Exchange (ETDEWEB)

    Demidovich, L.A.

    1977-06-01

    An examination is made of lithogenetic characteristics, zones of abnormally high collector properties are identified, and the formation time of reservoirs and oil deposits in Devonian layers of the Pripyat trough are established on the basis of studying the reflective capability of vitrinite, reservoir parameters and post-sedimentation processes. 2 tables, 1 figure, 5 references.

  19. Development of a X-ray micro-tomograph and its application to reservoir rocks characterization; Developpement d`un microtomographe X et application a la caracterisation des roches reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira de Paiva, R.

    1995-10-01

    We describe the construction and application to studies in three dimensions of a laboratory micro-tomograph for the characterisation of heterogeneous solids at the scale of a few microns. The system is based on an electron microprobe and a two dimensional X-ray detector. The use of a low beam divergence for image acquisition allows use of simple and rapid reconstruction software whilst retaining reasonable acquisition times. Spatial resolutions of better than 3 microns in radiography and 10 microns in tomography are obtained. The applications of microtomography in the petroleum industry are illustrated by the study of fibre orientation in polymer composites, of the distribution of minerals and pore space in reservoir rocks, and of the interaction of salt water with a model porous medium. A correction for X-ray beam hardening is described and used to obtain improved discrimination of the phases present in the sample. In the case of a North Sea reservoir rock we show the possibility to distinguish quartz, feldspar and in certain zone kaolinite. The representativeness of the tomographic reconstruction is demonstrated by comparing the surface of the reconstructed specimen with corresponding images obtained in scanning electron microscopy. (author). 58 refs., 10 tabs., 71 photos.

  20. Quantifying Fracture Heterogeneity in Different Domains of Folded Carbonate Rocks to Improve Fractured Reservoir Analog Fluid Flow Models

    NARCIS (Netherlands)

    Bisdom, K.; Bertotti, G.; Gauthier, B.D.M.; Hardebol, N.J.

    2013-01-01

    Fluid flow in carbonate reservoirs is largely controlled by multiscale fracture networks. Significant variations of fracture network porosity and permeability are caused by the 3D heterogeneity of the fracture network characteristics, such as intensity, orientation and size. Characterizing fracture

  1. Chemical, mineralogical and molecular biological characterization of the rocks and fluids from a natural gas storage deep reservoir as a baseline for the effects of geological hydrogen storage

    Science.gov (United States)

    Morozova, Daria; Kasina, Monika; Weigt, Jennifer; Merten, Dirk; Pudlo, Dieter; Würdemann, Hilke

    2014-05-01

    Planned transition to renewable energy production from nuclear and CO2-emitting power generation brings the necessity for large scale energy storage capacities. One possibility to store excessive energy produced is to transfer it to chemical forms like hydrogen which can be subsequently injected and stored in subsurface porous rock formations like depleted gas reservoirs and presently used gas storage sites. In order to investigate the feasibility of the hydrogen storage in the subsurface, the collaborative project H2STORE ("hydrogen to store") was initiated. In the scope of this project, potential reactions between microorganism, fluids and rocks induced by hydrogen injection are studied. For the long-term experiments, fluids of natural gas storage are incubated together with rock cores in the high pressure vessels under 40 bar pressure and 40° C temperature with an atmosphere containing 5.8% He as a tracer gas, 3.9% H2 and 90.3% N2. The reservoir is located at a depth of about 2 000 m, and is characterized by a salinity of 88.9 g l-1 NaCl and a temperature of 80° C and therefore represents an extreme environment for microbial life. First geochemical analyses showed a relatively high TOC content of the fluids (about 120 mg l-1) that were also rich in sodium, potassium, calcium, magnesium and iron. Remarkable amounts of heavy metals like zinc and strontium were also detected. XRD analyses of the reservoir sandstones revealed the major components: quartz, plagioclase, K-feldspar, anhydrite and analcime. The sandstones were intercalated by mudstones, consisting of quartz, plagioclase, K-feldspar, analcime, chlorite, mica and carbonates. Genetic profiling of amplified 16S rRNA genes was applied to characterize the microbial community composition by PCR-SSCP (PCR-Single-Strand-Conformation Polymorphism) and DGGE (Denaturing Gradient Gel Electrophoresis). First results indicate the presence of microorganisms belonging to the phylotypes alfa-, beta- and gamma

  2. Effects of fault-controlled CO2 alteration on mineralogical and geomechanical properties of reservoir and seal rocks, Crystal Geyser, Green River, Utah

    Science.gov (United States)

    Major, J. R.; Eichhubl, P.; Urquhart, A.; Dewers, T. A.

    2012-12-01

    An understanding of the coupled chemical and mechanical properties of reservoir and seal units undergoing CO2 injection is critical for modeling reservoir behavior in response to the introduction of CO2. The implementation of CO2 sequestration as a mitigation strategy for climate change requires extensive risk assessment that relies heavily on computer models of subsurface reservoirs. Numerical models are fundamentally limited by the quality and validity of their input parameters. Existing models generally lack constraints on diagenesis, failing to account for the coupled geochemical or geomechanical processes that affect reservoir and seal unit properties during and after CO2 injection. For example, carbonate dissolution or precipitation after injection of CO2 into subsurface brines may significantly alter the geomechanical properties of reservoir and seal units and thus lead to solution-enhancement or self-sealing of fractures. Acidified brines may erode and breach sealing units. In addition, subcritical fracture growth enhanced by the presence of CO2 could ultimately compromise the integrity of sealing units, or enhance permeability and porosity of the reservoir itself. Such unknown responses to the introduction of CO2 can be addressed by laboratory and field-based observations and measurements. Studies of natural analogs like Crystal Geyser, Utah are thus a critical part of CO2 sequestration research. The Little Grand Wash and Salt Wash fault systems near Green River, Utah, host many fossil and active CO2 seeps, including Crystal Geyser, serving as a faulted anticline CO2 reservoir analog. The site has been extensively studied for sequestration and reservoir applications, but less attention has been paid to the diagenetic and geomechanical aspects of the fault zone. XRD analysis of reservoir and sealing rocks collected along transects across the Little Grand Wash Fault reveal mineralogical trends in the Summerville Fm (a siltstone seal unit) with calcite and

  3. Pore Characterization of Shale Rock and Shale Interaction with Fluids at Reservoir Pressure-Temperature Conditions Using Small-Angle Neutron Scattering

    Science.gov (United States)

    Ding, M.; Hjelm, R.; Watkins, E.; Xu, H.; Pawar, R.

    2015-12-01

    Oil/gas produced from unconventional reservoirs has become strategically important for the US domestic energy independence. In unconventional realm, hydrocarbons are generated and stored in nanopores media ranging from a few to hundreds of nanometers. Fundamental knowledge of coupled thermo-hydro-mechanical-chemical (THMC) processes that control fluid flow and propagation within nano-pore confinement is critical for maximizing unconventional oil/gas production. The size and confinement of the nanometer pores creates many complex rock-fluid interface interactions. It is imperative to promote innovative experimental studies to decipher physical and chemical processes at the nanopore scale that govern hydrocarbon generation and mass transport of hydrocarbon mixtures in tight shale and other low permeability formations at reservoir pressure-temperature conditions. We have carried out laboratory investigations exploring quantitative relationship between pore characteristics of the Wolfcamp shale from Western Texas and the shale interaction with fluids at reservoir P-T conditions using small-angle neutron scattering (SANS). We have performed SANS measurements of the shale rock in single fluid (e.g., H2O and D2O) and multifluid (CH4/(30% H2O+70% D2O)) systems at various pressures up to 20000 psi and temperature up to 150 oF. Figure 1 shows our SANS data at different pressures with H2O as the pressure medium. Our data analysis using IRENA software suggests that the principal changes of pore volume in the shale occurred on smaller than 50 nm pores and pressure at 5000 psi (Figure 2). Our results also suggest that with increasing P, more water flows into pores; with decreasing P, water is retained in the pores.

  4. Magnetic-resonance imaging and simplified Kozeny-Carman-model analysis of glass-bead packs as a frame of reference to study permeability of reservoir rocks

    Science.gov (United States)

    Wang, Dayong; Han, Dongyan; Li, Wenqiang; Zheng, Zhanpeng; Song, Yongchen

    2017-03-01

    Permeability variation in reservoir rocks results from the combined effects of various factors, and makes porosity-permeability (ϕ-k) relationships more complex, or, in some cases, non-existent. In this work, the ϕ-k relationship of macroscopically homogeneous glass-bead packs is deduced based on magnetic resonance imaging (MRI) measurement and Kozeny-Carman (K-C) model analysis; these are used as a frame of reference to study permeability of reservoir rocks. The results indicate: (1) most of the commonly used simplified K-C models (e.g. the simplified traditional (omitting specific surface area), high-order, threshold, and fractal models) are suitable for estimating permeability of glass-bead packs. The simplified traditional model does not present obvious dependence on rock samples. Whether for the glass-bead packs or clean natural sandstones, the sample coefficients almost remain invariant. Comparably, the high-order, the fractal, and the threshold models are strongly sample-specific and cannot be extrapolated from the glass-bead packs to natural sandstones; (2) the ϕ-k relationships of quartz sands and silty sandstones resemble those of the glass-bead packs, but they significantly deviate from the K-C models at low porosities due to small pore entry radius; (3) a small amount of intergranular cements (<10%v) does not affect the general variation trend of permeability with porosity but can potentially increase predictive errors of the K-C models, whereas in the case of more cements, the ϕ-k relationships of sandstones become uncertain and cannot be described by any of these K-C models.

  5. Magnetic-resonance imaging and simplified Kozeny-Carman-model analysis of glass-bead packs as a frame of reference to study permeability of reservoir rocks

    Science.gov (United States)

    Wang, Dayong; Han, Dongyan; Li, Wenqiang; Zheng, Zhanpeng; Song, Yongchen

    2017-08-01

    Permeability variation in reservoir rocks results from the combined effects of various factors, and makes porosity-permeability ( ϕ- k) relationships more complex, or, in some cases, non-existent. In this work, the ϕ- k relationship of macroscopically homogeneous glass-bead packs is deduced based on magnetic resonance imaging (MRI) measurement and Kozeny-Carman (K-C) model analysis; these are used as a frame of reference to study permeability of reservoir rocks. The results indicate: (1) most of the commonly used simplified K-C models (e.g. the simplified traditional (omitting specific surface area), high-order, threshold, and fractal models) are suitable for estimating permeability of glass-bead packs. The simplified traditional model does not present obvious dependence on rock samples. Whether for the glass-bead packs or clean natural sandstones, the sample coefficients almost remain invariant. Comparably, the high-order, the fractal, and the threshold models are strongly sample-specific and cannot be extrapolated from the glass-bead packs to natural sandstones; (2) the ϕ- k relationships of quartz sands and silty sandstones resemble those of the glass-bead packs, but they significantly deviate from the K-C models at low porosities due to small pore entry radius; (3) a small amount of intergranular cements (<10%v) does not affect the general variation trend of permeability with porosity but can potentially increase predictive errors of the K-C models, whereas in the case of more cements, the ϕ- k relationships of sandstones become uncertain and cannot be described by any of these K-C models.

  6. STUDY ON THE PERMEABILITY OF CARBONATE ROCK GEOTHERMAL RESERVOIR IN BEIJING%北京地区碳酸盐岩热储渗透性研究

    Institute of Scientific and Technical Information of China (English)

    王树芳; 庞忠和; 何铁柱; 林沛; 刘凯; 刘久荣

    2014-01-01

    Beijing as capital of China is located in North China.The geothermal field in Beijing is mainly medium-low temperature conductive type,in which the Wumishan Formation with a thickness of more than 2000m of the Jixian System is the main reservoir and the rock of the Wumishan Formation is dolomite.Conductivity of the reservoir was usually calculated to understand reservoir characteristics, which could not accurately reflect permeability of the reservoir due to density variation of geothermal water.In order to understand permeability of the reservoir to direct geothermal resources development,porosity and permeability data of 34 dolomite rock cores collected from field outcrop and down-hole were compared and analyzed.The results indicated that permeability of outcrop and down-hole ranges are (10.0001 158 ~0.33333 )×10-3 μm2 and (0.0088 ~0.334 )×10-3 μm2 respectively,and the average value are 0.0622321×10-3μm2 and 0.385316×10-3μm2.The porosity ranges from 0.25%to 3.00%.The permeability of the rock cores are so low that geothermal energy could not be exacted without factures and fissures generated from tectonic movement and karstification.Therefore,permeability calculated from pump test could reflect total permeability of rock matrix,fractures and fissures.The calculated permeability of reservoir from 110 pump tests ranges from 13.74×10-3μm2 to 104474.00×10-3μm2,and the average is 4797.58× 10-3μm2.The cumulated percentage of permeability values between 100×10-3μm2 and 1000×10-3μm2 are more than 75%,the values less than 100×10-3μm2 are only 13.64%,and the permeability values greater than 100000× 10-3μm2 are 0.91 percent.In order to demonstrate relationship between reservoir buried depth and permeability, the buried depth were divided into 500m,500~1000m,1000~1500m,1500~2000m,2000~2500m,2500~3000m and 3000~3500m.The average permeability and average buried depth were plotted together in x,y coordi-nates.The results indicated that the average

  7. Modeling brine-rock interactions in an enhanced geothermal systemdeep fractured reservoir at Soultz-Sous-Forets (France): a joint approachusing two geochemical codes: frachem and toughreact

    Energy Technology Data Exchange (ETDEWEB)

    Andre, Laurent; Spycher, Nicolas; Xu, Tianfu; Vuataz,Francois-D.; Pruess, Karsten.

    2006-12-31

    The modeling of coupled thermal, hydrological, and chemical (THC) processes in geothermal systems is complicated by reservoir conditions such as high temperatures, elevated pressures and sometimes the high salinity of the formation fluid. Coupled THC models have been developed and applied to the study of enhanced geothermal systems (EGS) to forecast the long-term evolution of reservoir properties and to determine how fluid circulation within a fractured reservoir can modify its rock properties. In this study, two simulators, FRACHEM and TOUGHREACT, specifically developed to investigate EGS, were applied to model the same geothermal reservoir and to forecast reservoir evolution using their respective thermodynamic and kinetic input data. First, we report the specifics of each of these two codes regarding the calculation of activity coefficients, equilibrium constants and mineral reaction rates. Comparisons of simulation results are then made for a Soultz-type geothermal fluid (ionic strength {approx}1.8 molal), with a recent (unreleased) version of TOUGHREACT using either an extended Debye-Hueckel or Pitzer model for calculating activity coefficients, and FRACHEM using the Pitzer model as well. Despite somewhat different calculation approaches and methodologies, we observe a reasonably good agreement for most of the investigated factors. Differences in the calculation schemes typically produce less difference in model outputs than differences in input thermodynamic and kinetic data, with model results being particularly sensitive to differences in ion-interaction parameters for activity coefficient models. Differences in input thermodynamic equilibrium constants, activity coefficients, and kinetics data yield differences in calculated pH and in predicted mineral precipitation behavior and reservoir-porosity evolution. When numerically cooling a Soultz-type geothermal fluid from 200 C (initially equilibrated with calcite at pH 4.9) to 20 C and suppressing mineral

  8. Variations of the petrophysical properties of rocks with increasing hydrocarbons content and their implications at larger scale: insights from the Majella reservoir (Italy)

    Science.gov (United States)

    Trippetta, Fabio; Ruggieri, Roberta; Lipparini, Lorenzo

    2016-04-01

    Crustal processes such as deformations or faulting are strictly related to the petrophysical properties of involved rocks. These properties depend on mineral composition, fabric, pores and any secondary features such as cracks or infilling material that may have been introduced during the whole diagenetic and tectonic history of the rock. In this work we investigate the role of hydrocarbons (HC) in changing the petrophysical properties of rock by merging laboratory experiments, well data and static models focusing on the carbonate-bearing Majella reservoir. This reservoir represent an interesting analogue for the several oil fields discovered in the subsurface in the region, allowing a comparison of a wide range of geological and geophysical data at different scale. The investigated lithology is made of high porosity ramp calcarenites, structurally slightly affected by a superimposed fracture system and displaced by few major normal faults, with some minor strike-slip movements. Sets of rock specimens were selected in the field and in particular two groups were investigated: 1. clean rocks (without oil) and 2. HC bearing rocks (with different saturations). For both groups, density, porosity, P and S wave velocity, permeability and elastic moduli measurements at increasing confining pressure were conducted on cylindrical specimens at the HP-HT Laboratory of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome, Italy. For clean samples at ambient pressure, laboratory porosity varies from 10 % up to 26 % and P wave velocity (Vp) spans from 4,1 km/s to 4,9 km/s and a very good correlation between Vp, Vs and porosity is observed. The P wave velocity at 100 MPa of confining pressure, ranges between 4,5 km/s and 5,2 km/s with a pressure independent Vp/Vs ratio of about 1,9. The presence of HC within the samples affects both Vp and Vs. In particular velocities increase with the presence of hydrocarbons proportionally respect to the amount of the filled

  9. Experimental investigation of geochemical and mineralogical effects of CO2 sequestration on flow characteristics of reservoir rock in deep saline aquifers.

    Science.gov (United States)

    Rathnaweera, T D; Ranjith, P G; Perera, M S A

    2016-01-01

    Interactions between injected CO2, brine, and rock during CO2 sequestration in deep saline aquifers alter their natural hydro-mechanical properties, affecting the safety, and efficiency of the sequestration process. This study aims to identify such interaction-induced mineralogical changes in aquifers, and in particular their impact on the reservoir rock's flow characteristics. Sandstone samples were first exposed for 1.5 years to a mixture of brine and super-critical CO2 (scCO2), then tested to determine their altered geochemical and mineralogical properties. Changes caused uniquely by CO2 were identified by comparison with samples exposed over a similar period to either plain brine or brine saturated with N2. The results show that long-term reaction with CO2 causes a significant pH drop in the saline pore fluid, clearly due to carbonic acid (as dissolved CO2) in the brine. Free H(+) ions released into the pore fluid alter the mineralogical structure of the rock formation, through the dissolution of minerals such as calcite, siderite, barite, and quartz. Long-term CO2 injection also creates a significant CO2 drying-out effect and crystals of salt (NaCl) precipitate in the system, further changing the pore structure. Such mineralogical alterations significantly affect the saline aquifer's permeability, with important practical consequences for the sequestration process.

  10. Establishing the Relationship between Fracture-Related Dolomite and Primary Rock Fabric on the Distribution of Reservoirs in the Michigan Basin

    Energy Technology Data Exchange (ETDEWEB)

    G. Michael Grammer

    2006-09-30

    This topical report covers the year 2 of the subject 3-year grant, evaluating the relationship between fracture-related dolomite and dolomite constrained by primary rock fabric in the 3 most prolific reservoir intervals in the Michigan Basin (Ordovician Trenton-Black River Formations; Silurian Niagara Group; and the Devonian Dundee Formation). The characterization of select dolomite reservoirs has been the major focus of our efforts in Phase II/Year 2. Fields have been prioritized based upon the availability of rock data for interpretation of depositional environments, fracture density and distribution as well as thin section, geochemical, and petrophysical analyses. Structural mapping and log analysis in the Dundee (Devonian) and Trenton/Black River (Ordovician) suggest a close spatial relationship among gross dolomite distribution and regional-scale, wrench fault related NW-SE and NE-SW structural trends. A high temperature origin for much of the dolomite in the 3 studied intervals (based upon initial fluid inclusion homogenization temperatures and stable isotopic analyses,) coupled with persistent association of this dolomite in reservoirs coincident with wrench fault-related features, is strong evidence for these reservoirs being influenced by hydrothermal dolomitization. For the Niagaran (Silurian), a comprehensive high resolution sequence stratigraphic framework has been developed for a pinnacle reef in the northern reef trend where we had 100% core coverage throughout the reef section. Major findings to date are that facies types, when analyzed at a detailed level, have direct links to reservoir porosity and permeability in these dolomites. This pattern is consistent with our original hypothesis of primary facies control on dolomitization and resulting reservoir quality at some level. The identification of distinct and predictable vertical stacking patterns within a hierarchical sequence and cycle framework provides a high degree of confidence at this point

  11. Determining the relationship of thermal conductivity and compressional wave velocity of common rock types as a basis for reservoir characterization

    Science.gov (United States)

    Mielke, P.; Bär, K.; Sass, I.

    2017-05-01

    A comprehensive dataset detailing thermal conductivity and acoustic (compressional) wave velocity of 1430 oven-dry rock samples from clastic sedimentary (sandstone, arkose, greywacke), carbonatic (limestone, marl, dolomite, marble, coquina), plutonic (gabbro, gabbrodiorite, diorite, granodiorite, granite) and volcanic (basalt, andesite, rhyolite) rock types is presented. Correlation of thermal conductivity, compressional wave velocity and porosity are discussed in detail for each tested rock type. The study confirms that thermal conductivity of dry rocks can be predicted from acoustic velocity for porous rock types such as volcanites and sandstones, while non- and low-porous rocks show no to minor trends. With a prediction accuracy ± 0.5 W m- 1 K- 1 and a confidence of > 80% for sediments and mafic volcanites the calculated data is far more comprehensive than data collected from literature, and is likely accurate enough for most first exploration approaches or geoscientific models before detailed site-scale investigation or modelling is conducted. To investigate the effect of water saturation on thermal conductivity and compressional wave velocity 118 sedimentary samples (arkose and fine-, medium- and coarse sandstones) were saturated in de-aired water and the heat conduction and acoustic velocity were remeasured. The obtained data shows that both thermal conductivity and compressional wave velocity of saturated samples markedly increase in contrast to dry samples. The extent of the thermal conductivity and compressional wave velocity gain is mainly controlled by porosity. Thermal conductivity of saturated samples increases twice as much for higher porous samples than for low porous fine and medium sandstones. In contrast, the gain of compressional wave velocity of saturated sandstones decreases with increasing porosity.

  12. 库岸公路岩石边坡极限破坏角研究%On the critical angle deformation of reservoir bank highway rock slopes

    Institute of Scientific and Technical Information of China (English)

    周志军

    2012-01-01

    为了准确评价库岸公路岩石边坡的稳定性,合理指导工程施工,保证开挖边坡安全,考虑发生连续降雨、洪水等引起库水位抬高后,库岸公路岩石边坡滑动面处于饱水状态时的滑动面渗水压力,建立了渗压效应下岩石边坡的滑动简化模型.然后进行边坡上力的分析推导,得出边坡的坡高、坡角和极限破坏角之间的关系式,并对关系式进行求解,得出库岸公路岩石边坡极限破坏角公式.最后利用该公式对安康至陕川界高速公路沿线典型边坡计算并进行回归分析,得出沿线边坡坡高和坡角之间的关系式和极限破坏角公式.计算结果与实际相符.%This paper takes its main interest in the study of the critical angle deformation of reservoir bank highway rock slopes. As is known, a lot of methods and models are used for the time being to assess the stability of such deformation,for example, the limit equilibrium method and catastrophe theory. Statistically speaking,over 90% of the rock slope failure involves groundwater penetration or permeating, which implies that water is a key factor affecting the slope stability . However, it is rare for the researchers of rock slope to pay enough attention to studying the seepage pressure of sliding surface on the slope stability. Seeing the above said factors, the author of this paper is willing to turn the our direction to and take into full account such factors, as the continuous rainfall, flood discharge and so on, which may cause upraise of water level in the reservoir, in better assessing the stability of reservoir banks highway rock slope along with giving proper directions to water-conservation and highway-building engineering projects. In doing so, first of all, we have established a simplified model of sliding slope in condition of infiltration pressure, when gliding deformation of such rock slopes in case of water-saturated. And, then, the correlation equation can be derived

  13. How temperature-dependent elasticity alters host rock/magmatic reservoir models: A case study on the effects of ice-cap unloading on shallow volcanic systems

    Science.gov (United States)

    Bakker, Richard R.; Frehner, Marcel; Lupi, Matteo

    2016-12-01

    In geodynamic numerical models of volcanic systems, the volcanic basement hosting the magmatic reservoir is often assumed to exhibit constant elastic parameters with a sharp transition from the host rocks to the magmatic reservoir. We assess this assumption by deriving an empirical relation between elastic parameters and temperature for Icelandic basalts by conducting a set of triaxial compression experiments between 200 °C and 1000 °C. Results show a significant decrease of Young's modulus from ∼38 GPa to less than 4.7 GPa at around 1000 °C. Based on these laboratory data, we develop a 2D axisymmetric finite-element model including temperature-dependent elastic properties of the volcanic basement. As a case study, we use the Snæfellsjökull volcanic system, Western Iceland to evaluate pressure differences in the volcanic edifice and basement due to glacial unloading of the volcano. First, we calculate the temperature field throughout the model and assign elastic properties accordingly. Then we assess unloading-driven pressure differences in the magma chamber at various depths in models with and without temperature-dependent elastic parameters. With constant elastic parameters and a sharp transition between basement and magma chamber we obtain results comparable to other studies. However, pressure changes due to surface unloading become smaller when using more realistic temperature-dependent elastic properties. We ascribe this subdued effect to a transition zone around the magma chamber, which is still solid rock but with relatively low Young's modulus due to high temperatures. We discuss our findings in the light of volcanic processes in proximity to the magma chamber, such as roof collapse, dyke injection, or deep hydrothermal circulation. Our results aim at quantifying the effects of glacial unloading on magma chamber dynamics and volcanic activity.

  14. Oil biodegradation by Bacillus strains isolated from the rock of an oil reservoir located in a deep-water production basin in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Duarte da Cunha, C.; Rosado, A.S.; Seldin, L.; Weid, I. von der [Universidade Federal do Rio de Janeiro (Brazil). Dept. de Microbiologia Geral; Sebastian, G.V. [CENPES, Petrobras, Ilha do Fundao, Rio de Janeiro (Brazil)

    2006-12-15

    Sixteen spore forming Gram-positive bacteria were isolated from the rock of an oil reservoir located in a deep-water production basin in Brazil. These strains were identified as belonging to the genus Bacillus using classical biochemical techniques and API 50CH kits, and their identity was confirmed by sequencing of part of the 16S rRNA gene. All strains were tested for oil degradation ability in microplates using Arabian Light and Marlin oils and only seven strains showed positive results in both kinds of oils. They were also able to grow in the presence of carbazole, n-hexadecane and polyalphaolefin (PAO), but not in toluene, as the only carbon sources. The production of key enzymes involved with aromatic hydrocarbons biodegradation process by Bacillus strains (catechol 1,2-dioxygenase and catechol 2,3-dioxygenase) was verified spectrophotometrically by detection of cis,cis-muconic acid and 2-hydroxymuconic semialdehyde, and results indicated that the ortho ring cleavage pathway is preferential. Furthermore, polymerase chain reaction (PCR) products were obtained when the DNA of seven Bacillus strains were screened for the presence of catabolic genes encoding alkane monooxygenase, catechol 1,2-dioxygenase, and/or catechol 2,3-dioxygenase. This is the first study on Bacillus strains isolated from an oil reservoir in Brazil. (orig.)

  15. Economics of a 75-MW(e) hot-dry-rock geothermal power station based upon the design of the Phase II reservoir at Fenton Hill

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, H.; Drake, R.; Tester, J.; Zyvoloski, G.

    1982-02-01

    Based upon EE-2 and EE-3 drilling costs and the proposed Fenton Hill Phase II reservoir conditions the break-even cost of producing electricity is 4.4 cents per kWh at the bus bar. This cost is based upon a 9-well, 12-reservoir hot dry rock (HDR) system producing 75 MW(e) for 10 yr with only 20% drawdown, and an assumed annual finance charge of 17%. Only one-third of the total, potentially available heat was utilized; potential reuse of wells as well as thermal stress cracking and augmentation of heat transfer was ignored. Nearly half the bus bar cost is due to drilling expenses, which prompted a review of past costs for wells GT-2, EE-1, EE-2, and EE-3. Based on comparable depth and completion times it is shown that significant cost improvements have been accomplished in the last seven years. Despite these improvements it was assumed for this study that no further advancements in drilling technology would occur, and that even in commercially mature HDR systems, drilling problems would continue nearly unabated.

  16. Evaluation of the efficiency of injection of polyacrylamide in different reservoir-rock samples; Avaliacao da eficiencia de injecao de poliacrilamida em diferentes amostras de rocha-reservatorio

    Energy Technology Data Exchange (ETDEWEB)

    Marcelino, Cleuton P.; Valentim, Adriano C.M.; Medeiros, Ana Catarina R. de; Girao, Joaquim H.S.; Barcia, Rosangela B. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2004-07-01

    Water soluble polymers have been used extensively in the petroleum recovery, due to their ability in increasing the viscosity of the injection water and to reduce water/oil mobility ratio and the water relative permeability in the reservoir. This reduction acts favorably as a secondary effect, and it reestablishes part of the pressure in the reservoir after the flow of the polymer, causing a correction of the injection profile in the wells through the restructuring of the resident fluids in the porous media. Nevertheless, some parameters influence the improve of this mechanism, such as petrophysics properties, chemical composition of the rock, adsorption, resistance factor and the residual resistance factor. Many paper in the area of polymers applied to the enhanced petroleum recovery indicate a high efficiency in the injection of different partially hydrolysed polyacrylamides, in different concentrations, or even in different injection conditions, as: temperature, flow, among others. In this work it was evaluated the behavior and efficiency of partially hydrolysed polyacrylamide flooding on outcrop cores from Botucatu, Rio Bonito, Clashach and Assu, using core flow tests and computer simulations. (author)

  17. Gas sealing efficiency of cap rocks. Pt. 1: Experimental investigations in pelitic sediment rocks. - Pt. 2: Geochemical investigations on redistribution of volatile hydrocarbons in the overburden of natural gas reservoirs; Gas sealing efficiency of cap rocks. T. 1: Experimentelle Untersuchungen in pelitischen Sedimentgesteinen. - T.2: Geochemische Untersuchungen zur Umverteilung leichtfluechtiger Kohlenwasserstoffe in den Deckschichten von Erdgaslagerstaetten. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Leythaeuser; Konstanty, J.; Pankalla, F.; Schwark, L.; Krooss, B.M.; Ehrlich, R.; Schloemer, S.

    1997-09-01

    New methods and concepts for the assessment of sealing properties of cap rocks above natural gas reservoirs and of the migration behaviour of low molecular-weight hydrocarbons in sedimentary basins were developed and tested. The experimental work comprised the systematic assesment of gas transport parameters on representative samples of pelitic rocks at elevated pressure and temperature conditions, and the characterization of their sealing efficiency as cap rocks overlying hydrocarbon accumulations. Geochemical case histories were carried out to analyse the distribution of low molecular-weight hydrocarbons in the overburden of known natural gas reservoirs in NW Germany. The results were interpreted with respect to the sealing efficiency of individual cap rock lithologies and the type and extent of gas losses. (orig.) [Deutsch] Zur Beurteilung der Abdichtungseigenschaften von Caprocks ueber Gaslagerstaetten und des Migrationsverhaltens niedrigmolekularer Kohlenwasserstoffe in Sedimentbecken wurden neue Methoden und Konzepte entwickelt und angewendet. In experimentellen Arbeiten erfolgte die systematische Bestimmung von Gas-Transportparametern an repraesentativen Proben pelitischer Gesteine unter erhoehten Druck- und Temperaturbedingungen und die Charakterisierung ihrer Abdichtungseffizienz als Deckschicht ueber Kohlenwasserstofflagerstaetten. In geochemischen Fallstudien wurde die Verteilung niedrigmolekularer Kohlenwasserstoffe in den Deckschichten ueber bekannten Erdgaslagerstaetten in NW-Deutschland analysiert und im Hinblick auf die Abdichtungseffizienz einzelner Caprock-Lithologien bzw. Art und Ausmass von Gasverlusten interpretiert. (orig.)

  18. 柏叶口水库大坝过渡料开采与加工%Quarrying and Processing Dam-body's Intermediate Rock Material in Baiyekou Reservoir

    Institute of Scientific and Technical Information of China (English)

    任佳; 石芮; 石建军

    2011-01-01

    柏叶口水库大坝过渡料采取了人工轧制的办法加工生产,文中介绍了过渡区石料级配的设计要求,石料的开采与加工,石料加工结果的质量监测。%The artifical crushing method is used to process dam-body's intermediate rock material in Baiyekou Reservoir.The paper introduces the design demand of rock size gradation in dam-body's intermediate region,the rock material's quarrying and processing,the quality monitoring of processing result.

  19. Field demonstration of an active reservoir pressure management through fluid injection and displaced fluid extractions at the Rock Springs Uplift, a priority geologic CO2 storage site for Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Zunsheng [Univ. of Wyoming, Laramie, WY (United States)

    2017-04-05

    This report provides the results from the project entitled Field Demonstration of Reservoir Pressure Management through Fluid Injection and Displaced Fluid Extraction at the Rock Springs Uplift, a Priority Geologic CO2 Storage Site for Wyoming (DE-FE0026159 for both original performance period (September 1, 2015 to August 31, 2016) and no-cost extension (September 1, 2016 to January 6, 2017)).

  20. Major element, REE, and Pb, Nd and Sr isotopic geochemistry of Cenozoic volcanic rocks of eastern China: implications for their origin from suboceanic-type mantle reservoirs

    Science.gov (United States)

    Basu, A.R.; Wang, Junwen; Huang, Wankang; Xie, Guanghong; Tatsumoto, M.

    1991-01-01

    Major- and rare-earth-element (REE) concentrations and UThPb, SmNd, and RbSr isotope systematics are reported for Cenozoic volcanic rocks from northeastern and eastern China. These volcanic rocks, characteristically lacking the calc-alkaline suite of orogenic belts, were emplaced in a rift system which formed in response to the subduction of the western Pacific plate beneath the eastern Asiatic continental margin. The rocks sampled range from basanite and alkali olivine basalt, through olivine tholeiite and quartz tholeiite, to potassic basalts, alkali trachytes, pantellerite, and limburgite. These rock suites represent the volcanic centers of Datong, Hanobar, Kuandian, Changbaishan and Wudalianchi in northeastern China, and Mingxi in the Fujian Province of eastern China. The major-element and REE geochemistry is characteristic of each volcanic suite broadly evolving through cogenetic magmatic processes. Some of the outstanding features of the isotopic correlation arrays are as follows: (1) NdSr shows an anticorrelation within the field of ocean island basalts, extending from the MORB end-member to an enriched, time-averaged high Rb Sr and Nd Sr end-member (EM1), (2) SrPb also shows an anticorrelation, similar to that of Hawaiian and walvis Ridge basalts, (3) NdPb shows a positive correlation, and (4) the 207Pb 204Pb vs 206Pb 204Pb plot shows linear arrays parallel to the general trend (NHRL) for MORB on both sides of the geochron, although in the 208Pb 204Pb vs 206Pb 204Pb plot the linear array is significantly displaced above the NHRL in a pattern similar to that of the oceanic island basalts that show the Dupal signatures. In all isotope correlation patterns, the data arrays define two different mantle components-a MORB-like component and an enriched mantle component. The isotopic data presented here clearly demonstrate the existence of Dupal compositions in the sources of the continental volcanic rocks of eastern China. We suggest that the subcontinental mantle

  1. Study on Relation between Hydrodynamic Feature Size of HPAM and Pore Size of Reservoir Rock in Daqing Oilfield

    Directory of Open Access Journals (Sweden)

    Qing Fang

    2015-01-01

    Full Text Available The flow mechanism of the injected fluid was studied by the constant pressure core displacement experiments in the paper. It is assumed under condition of the constant pressure gradient in deep formation based on the characteristic of pressure gradient distribution between the injection and production wells and the mobility of different polymer systems in deep reservoir. Moreover, the flow rate of steady stream was quantitatively analyzed and the critical flow pressure gradient of different injection parameters polymer solutions in different permeability cores was measured. The result showed that polymer hydrodynamic feature size increases with the increasing molecular weight. If the concentration of polymer solutions overlaps beyond critical concentration, then molecular chains entanglement will be occur and cause the augment of its hydrodynamic feature size. The polymer hydrodynamic feature size decreased as the salinity of the dilution water increased. When the median radius of the core pore and throat was 5–10 times of the polymer system hydrodynamic feature size, the polymer solution had a better compatibility with the microscopic pore structure of the reservoir. The estimation of polymer solutions mobility in the porous media can be used to guide the polymer displacement plan and select the optimum injection parameters.

  2. Modeling the Use of Mine Waste Rock as a Porous Medium Reservoir for Compressed Air Energy Storage

    Science.gov (United States)

    Donelick, R. A.; Donelick, M. B.

    2016-12-01

    We are studying the engineering and economic feasibilities of constructing Big Mass Battery (BiMBy) compressed air energy storage devices using some of the giga-tonnes of annually generated and historically produced mine waste rock/overburden/tailings (waste rock). This beneficial use of waste rock is based on the large mass (Big Mass), large pore volume, and wide range of waste rock permeabilities available at some large open pit metal mines and coal strip mines. Porous Big Mass is encapsulated and overlain by additional Big Mass; compressed air is pumped into the encapsulated pore space when renewable energy is abundant; compressed air is released from the encapsulated pore space to run turbines to generate electricity at the grid scale when consumers demand electricity. Energy storage capacity modeling: 1) Yerington Pit, Anaconda Copper Mine, Yerington, NV (inactive metal mine): 340 Mt Big Mass, energy storage capacity equivalent to 390k-710k home batteries of size 10 kW•h/charge, assumed 20% porosity, 50% overall efficiency. 2) Berkeley Pit, Butte Copper Mine, Butte, MT (inactive metal mine): 870 Mt Big Mass, energy storage capacity equivalent to 1.4M-2.9M home batteries of size 10 kW•h/charge, assumed 20% porosity, 50% overall efficiency. 3) Rosebud Mine, Colstrip, MT (active coal strip mine): 87 Mt over 2 years, energy storage capacity equivalent to 45k-67k home batteries of size 10 kW•h/charge, assumed 30% porosity, 50% overall efficiency. Encapsulating impermeable layer modeling: Inactive mine pits like Yerington Pit and Berkeley Pit, and similar active pits, have associated with them low permeability earthen material (silt and clay in Big Mass) at sufficient quantities to manufacture an encapsulating structure with minimal loss of efficiency due to leakage, a lifetime of decades or even centuries, and minimal need for the use of geomembranes. Active coal strip mines like Rosebud mine have associated with them low permeability earthen material such as

  3. A direct method for determining complete positive and negative capillary pressure curves for reservoir rock using the centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Spinler, E.A.; Baldwin, B.A. [Phillips Petroleum Co., Bartlesville, OK (United States)

    1997-08-01

    A method is being developed for direct experimental determination of capillary pressure curves from saturation distributions produced during centrifuging fluids in a rock plug. A free water level is positioned along the length of the plugs to enable simultaneous determination of both positive and negative capillary pressures. Octadecane as the oil phase is solidified by temperature reduction while centrifuging to prevent fluid redistribution upon removal from the centrifuge. The water saturation is then measured via magnetic resonance imaging. The saturation profile within the plug and the calculation of pressures for each point of the saturation profile allows for a complete capillary pressure curve to be determined from one experiment. Centrifuging under oil with a free water level into a 100 percent water saturated plug results in the development of a primary drainage capillary pressure curve. Centrifuging similarly at an initial water saturation in the plug results in the development of an imbibition capillary pressure curve. Examples of these measurements are presented for Berea sandstone and chalk rocks.

  4. Characterization of a hot dry rock reservoir at Acoculco geothermal zone, Pue.; Caracterizacion de un yacimiento de roca seca caliente en la zona geotermica de Acoculco, Pue.

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo Pulido, Cecilia; Flores Armenta, Magaly Ramirez Silva, German [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: cecilia-lorenzo@cfe.gob.mx

    2011-01-15

    Hot dry rock (HDR) geothermal resources, also called enhanced (or engineered) geothermal systems (EGS), have been researched for a long time. The HDR concept is simple. Most of the reservoirs are found at depths of around 5000 m and comprised of impermeable rocks at temperatures between 150 degrees Celsius and 300 degrees Celsius -lacking fluid. Rock temperature is a main economic criterion, since to generate electric energy initial temperatures above 200 degrees Celsius are required. To develop a HDR system, two wells are drilled. Cold water is introduced in one well and hot water is obtained from the other well by passing the water through the hot rock. Since June 2008, a 1.5 MWe power plant has been operating in France, part of the Soultz-sous-Foret project financed by the European Deep Geothermal Energy Programme. To characterize the HDR reservoir multi-disciplinary information was gathered regarding: (1) the heat source origin, (2) qualitative information on temperature and transfer mechanisms of natural heat, (3) natural faults and fractures, (4) local stresses, and (5) the basement rock. The information was applied to a geothermal zone in Acoculco, Pue.. The zone was explored by the Exploration Department with wells EAC-1 and EAC-2, defining the presence of a high temperature reservoir (from 220 degrees Celsius to more than 250 degrees Celsius ). The zone presents the following features: (1) heat source origin: volcano-tectonic, (2) temperature logs show values of 263.8 degrees Celsius and 307.3 degrees Celsius at depths of 1900 m and 2000 m, respectively, (3) the exploration wells are located in a graben-like structure, and the core and cutting samples show evidences of natural faults and fractures partially or completely sealed by hydrothermal minerals such as epidote, quartz and pyrite, (4) stress analyses indicate the local NW-SE and E-W systems are the main systems in the geothermal zone, and (5) the basement rock is composed of limestones with contact

  5. Seismic modeling, rock physics, avo and seismic attribute analysis for illuminating sandstone facies of the Late Ordovic Ian Mamuniyat Reservoir, R-Field, Murzuq Basin-Libya

    Science.gov (United States)

    Abushalah, Yousf Milad

    The Late Ordovician Mamuniyat Formation is the main hydrocarbon reservoir in the R-Field in Murzuq Basin, SW Libya. The Lower Mamuniyat, which is the only unit that was encountered in the study area, is composed of sandstone facies called Clean Mamuniyat and shaly sandstone facies called Dirty Mamuniyat. One major problem with the development of the R-Field is the difficulty of distinguishing the two units so this project was aimed to develop better methods for distinguishing between the two units of the Lower Mamuniyat. The other problem is to distinguish the transgressive shaly facies of the Bir Tlacsin, which has an impact on the hydrocarbon accumulation. Those issues manifested in limit of seismic resolution and interference that resulted from the converted shear mode waves. The dissertation was divided into three chapters. In the first chapter, seismic modeling using a deterministic and a Ricker wavelet were used to investigate the interference effects on the poststack seismic data and a bandpass filter was used to remove those effects. Instantaneous frequency, spectral-based colored inversion and rock physics were, then applied to determine the distributions of the sandstone facies of the Lower Mamuniyat Formation and to interpret the depositional setting of it. In the second chapter, spectral decomposition and inverted density were utilized to determine the distribution of the shaly facies of Bir Tlacsin, and its temporal thickness and to remap the top reservoir. In the last chapter, amplitude variation with offset (AVO) modeling, ray tracing, and spectral analysis were used to investigate the mode conversion and its effect on AVO signature, the amplitude of the near-mid and far offsets and frequency contents. Data enhancement then was performed using partial stacks and a bandpass filter.

  6. 储层岩石水敏性影响因素研究%Influencing Factors of Water Sensitivity in Reservoir Rock

    Institute of Scientific and Technical Information of China (English)

    汪伟英; 唐周怀; 吕迎红; 杜燕; 赵磊

    2001-01-01

    注入流体矿化度与储层中的粘土矿物不配伍时,会引起粘土矿物水化膨胀和分散,导致渗透率降低。研究表明,岩石水敏损害程度与注入水盐度、盐度递减速率以及 pH值有关。当注入水盐度低于9000mg/L时,渗透率明显降低。盐度递减速率越快,水敏损害程度越大。酸性介质能抑制岩石水敏性而碱性介质会增强岩石水敏性。%When the salinity of injected fluid is not compatible with clay minerals in a reservoir,hydrated swell and dispersion of the clay minerals are caused,which makes permeability decreasing.The result of study indicates that the extent of damage induced by water sensitivity is related with salt content, its decreasing rate and pH. When the salt content is less than 9000 mg/L,permeability decreases evidently.The more rapid decrease in salt content,the more serious damage of water sensitivity.Water sensitivity of rock would be controlled by acidic medium,while it would be enhanced by alkaline medium.

  7. Data requirements and acquisition for reservoir characterization

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, S.; Chang, Ming Ming; Tham, Min.

    1993-03-01

    This report outlines the types of data, data sources and measurement tools required for effective reservoir characterization, the data required for specific enhanced oil recovery (EOR) processes, and a discussion on the determination of the optimum data density for reservoir characterization and reservoir modeling. The two basic sources of data for reservoir characterization are data from the specific reservoir and data from analog reservoirs, outcrops, and modern environments. Reservoir data can be divided into three broad categories: (1) rock properties (the container) and (2) fluid properties (the contents) and (3)interaction between reservoir rock and fluid. Both static and dynamic measurements are required.

  8. Characterizing a Mississippian Carbonate Reservoir for CO2-EOR and Carbon Geosequestration: Applicability of Existing Rock Physics Models and Implications to Feasibility of a Time Lapse Monitoring Program in the Wellington Oil Field, Sumner County, Kansas.

    Science.gov (United States)

    Lueck, A. J.; Raef, A. E.

    2015-12-01

    This study will focus on characterizing subsurface rock formations of the Wellington Field, in Sumner County, Kansas, for both geosequestration of carbon dioxide (CO2) in the saline Arbuckle formation and enhanced oil recovery of a depleting Mississippian oil reservoir. Multi-scale data including lithofacies core samples, X-ray diffraction, digital rock physics scans, scanning electron microscope (SEM) imaging, well log data including sonic and dipole sonic, and surface 3D seismic reflection data will be integrated to establish and/or validate a new or existing rock physics model that best represents our reservoir rock types and characteristics. We will acquire compressional wave velocity and shear wave velocity data from Mississippian and Arbuckle cores by running ultrasonic tests using an Ult 100 Ultrasonic System and a 12 ton hydraulic jack located in the geophysics lab in Thompson Hall at Kansas State University. The elastic constants Young's Modulus, Bulk Modulus, Shear (Rigidity) Modulus and Poisson's Ratio will be extracted from these velocity data. Ultrasonic velocities will also be compared to sonic and dipole sonic log data from the Wellington 1-32 well. These data will be integrated to validate a lithofacies classification statistical model, which will be and partially has been applied to the largely unknown saline Arbuckle formation, with hopes for a connection, perhaps via Poisson's ratio, allowing a time-lapse seismic feasibility assessment and potentially developing a transformation of compressional wave sonic velocities to shear wave sonic for all wells, where compressional wave sonic is available. We will also be testing our rock physics model by predicting effects of changing effective (brine + CO2 +hydrocarbon) fluid composition on seismic properties and the implications on feasibility of seismic monitoring. Lessons learned from characterizing the Mississippian are essential to understanding the potential of utilizing similar workflows for the

  9. A new method for determination of wettability of reservoir rocks.%一种定量测定油藏岩石润湿性的新方法

    Institute of Scientific and Technical Information of China (English)

    鄢捷年

    2001-01-01

    On the basis of previous work, a new method for the determination of wettability of reservoir rocks, which can be designated as the modified method of spontaneous imbibition, has been established. The method is provided based on the principle that the wettability of rock surfaces is a key factor affecting the spontaneous imbibition rate as the rock contacts fluids. The influence of oil/water interfacial tension, liquid viscosity, pore geometry, as well as the shape and size of core samples, can be eliminated by introducing a dimensionless time, tD, instead of the imbibition time. The wettability index of rock surfaces under a given condition, WR, was determined quantitatively from the pseudo capillary pressure curve measured in the process of imbibition. The larger the value of WR is, the stronger the water wetness will be. The magnitude of WR depends on the rate of spontaneous imbibition and the total volume of the imbibition liquid. The imbibition tests were conducted by suspending a core from an electronic balance and immersing it in brine. The constitution of brine used in this test should be the same as the brine used for establishing the initial water saturation. The change in weight of the suspended core versus time was monitored for the period of time from core immersing to the weight of the core keeping constant (usually 72h). The oil recovery by spontaneous imbibition, Rim, at a given time was calculated and the curve of Rim versus tD, was plotted from the change in core weight and the density difference between oil and brine. The pseudo capillary pressures, pc,ps, and water saturation, Sw, corresponding to various values of tD were calculated and the curve of pc,ps versus Sw was plotted. Finally, the wettability index, WR, for each core sample was determined from the area under this curve.The experimental results indicate that the wettability indices determined using this method is considerably comparable with the wettability indices, Iw-o, determined

  10. 阿塔山水库壤土心墙堆石坝施工工艺%Construction Technology of Loam Core-wall Rock-fill Dam of Atashan Reservoir Dam

    Institute of Scientific and Technical Information of China (English)

    秦美荣

    2015-01-01

    阿塔山水库大坝是大型壤土心墙堆石坝,通过精心组织、科学管理、严把质量,填筑质量满足规范设计要求,保质保量完成合同任务。%Atashan reservoir dam is a large loam core-wall rock-fill dam. Through the elaborate organization, scientific management and strict quality control, the filling quality meets the requirements of the specification design, and the contract task is completed with good quality.

  11. Preliminary design study of underground pumped hydro and compressed-air energy storage in hard rock. Volume 8: Design approaches: UPH. Appendix A: Upper reservoir

    Science.gov (United States)

    1981-04-01

    Overriding considerations including operating range, volume and lining of reservoir, embankment design, intake/outlet arrangements and filling and make up water provisions were studied within the context of minimizing facility costs and optimizing the plant layout. The study led to the selection of a reservoir formed by embankment of compacted rockfill together with an intake/outlet structure located in the embankment. The reservoir floor and upstream slopes of the embankment will have an asphalt lining to prevent leakage. The material and cost estimates presented are based on the requirements for a 2000 MW plant providing 20,000 MWh of storage with a nominal head of 4600 ft.

  12. Phase I (Year 1) Summary of Research--Establishing the Relationship between Fracture-Related Dolomite and Primary Rock Fabric on the Distribution of Reservoirs in the Michigan Basin

    Energy Technology Data Exchange (ETDEWEB)

    G. Michael Grammer

    2005-11-09

    This topical report covers the first 12 months of the subject 3-year grant, evaluating the relationship between fracture-related dolomite and dolomite constrained by primary rock fabric in the 3 most prolific reservoir intervals in the Michigan Basin (Ordovician Trenton-Black River Formations; Silurian Niagara Group; and the Devonian Dundee Formation). Phase I tasks, including Developing a Reservoir Catalog for selected dolomite reservoirs in the Michigan Basin, Characterization of Dolomite Reservoirs in Representative Fields and Technology Transfer have all been initiated and progress is consistent with our original scheduling. The development of a reservoir catalog for the 3 subject formations in the Michigan Basin has been a primary focus of our efforts during Phase I. As part of this effort, we currently have scanned some 13,000 wireline logs, and compiled in excess of 940 key references and 275 reprints that cover reservoir aspects of the 3 intervals in the Michigan Basin. A summary evaluation of the data in these publications is currently ongoing, with the Silurian Niagara Group being handled as a first priority. In addition, full production and reservoir parameter data bases obtained from available data sources have been developed for the 3 intervals in Excel and Microsoft Access data bases. We currently have an excess of 25 million cells of data for wells in the Basin. All Task 2 objectives are on time and on target for Phase I per our original proposal. Our mapping efforts to date, which have focused in large part on the Devonian Dundee Formation, have important implications for both new exploration plays and improved enhanced recovery methods in the Dundee ''play'' in Michigan--i.e. the interpreted fracture-related dolomitization control on the distribution of hydrocarbon reservoirs. In an exploration context, high-resolution structure mapping using quality-controlled well data should provide leads to convergence zones of fault

  13. Influences of diagenetic effects on volcanic rock reservoirs under two different sedimentary environments%两种不同沉积环境下火山岩储层成岩作用研究

    Institute of Scientific and Technical Information of China (English)

    王盛鹏; 林潼; 孙平; 梁浩; 王东良; 苟红光

    2012-01-01

    According to the studies of rock types and reservoir space features of Carboniferous volcanic rocks in the Santanghu Basin, there were two kinds of environments for volcanic rock generation including subaerial and subaqueous in the study area. Based on core description, casting chip, scanning electron microscopy and element analysis, the generation features of volcanic rocks under the two different environments and the corresponding influences on reservoirs were discussed from the aspects of diagenetic effects. It was concluded that different diagenetic effects influenced volcanic reservoirs in different extents. The volcanic rocks which erupted and deposited on land in the study area were severely filled by zeolites and chlorites, and then improved obviously due to weathering and leaching. The extent of weathering and leaching was closely related to the improvement of reservoir. The volcanic reservoirs which deposited under water were improved owing to organic acid erosion. Primary pores were seldom found and a large amount of matrix dissolved holes generated. The generation mechanisms of subaqueous volcanic reservoirs pointed out new areas for explorations in the future.%基于三塘湖盆地石炭系火山岩储层的岩石类型、储集空间特征研究,识别出该区存在陆上喷发沉积和水下沉积2种环境.并通过岩心描述、铸体薄片和扫描电镜微观显示以及元素分析等手段,重点从成岩作用的角度对这2种环境下火山岩储层的发育特征及影响作用开展研究.研究认为,各种成岩作用对火山岩储层起到了不同程度的影响作用.该区陆上喷发沉积的火山岩受沸石和绿泥石填充较强烈,后期又遭受风化淋滤作用,使得储层发生明显的改善;风化强度与储层改善有着密切关系.水下沉积的火山岩储层改善主要受有机酸溶蚀作用影响,其原生孔隙不发育,但发育大量的基质溶孔.对水下沉积火山岩储层发育机理的认

  14. 松辽盆地北部徐家围子断陷火山岩储层成因机制%Volcanic rock reservoirs mechanism in North Songliao Basin Xujiaweizi Fault Depression

    Institute of Scientific and Technical Information of China (English)

    韩刚; 张文婧; 任延广; 黄清华; 梁江平; 包丽

    2011-01-01

    松辽盆地北部徐家围子断陷徐深气田是我国迄今为止发现的最大的火山岩气田.营城组火山岩具有分布广、厚度大、岩性复杂等特点,既有酸性的流纹岩、流纹质熔结凝灰岩,也有中性的安山岩、安山质集块岩和基性的玄武岩.研究表明,酸性流纹岩、流纹质熔结凝灰岩普遍发育较好的原生气孔,而火山角砾岩、火山集块岩一般发育火山岩原生裂缝,这些为优质火山岩储层形成奠定了物质基础,成岩作用过程中深部流体活动和选择性溶蚀作用,不仅增大了火山岩的有效储集空间,同时也改善了火山岩储集层空间结构,而构造运动所形成的构造裂缝,不仅为深部流体活动和油气运移提供了主要通道,而且有效地增大了火山岩的油气储集空间.%The Xushen gas field locates in Xujiaweizi Fault Depression of North Songliao Basin. It is so far the greatest volcanic rock gas field in China. The Xushen gas field develops typical Yingcheng Formation volcanic rocks. The Yingcheng Formation volcanic rocks have such characteristic as extensive distribution range, great thickness, and complex lithology. By using methods such as core and scanning electron microscope observation, body of casting slice, analysis and assay, we found the lithology of Yingcheng Formation volcanic rocks consist of not only acidic rhyolite, rhyolite-cementing tuff, but also neutral andesite, andesite-agglomerate and basic basalt. We conducted subtly researchs. The purpose is to see into the cause-mechanism of volcanic rocks reservoirs, and then provide reliable evidences in conducting oil-gas exploration, seeking favorable reservoirs and improving the success rate of prospecting well. Researches have made clearly that acidic rhyolite, rhyolite-cementing tuffs develop generally preferable original pore, but volcanic breccias and volcanic agglomerates commonly develop volcanic primary fracture. These establish foundation for

  15. An Integrated Rock Typing Approach for Unraveling the Reservoir Heterogeneity of Tight Sands in the Whicher Range Field of Perth Basin, Western Australia

    DEFF Research Database (Denmark)

    Ilkhchi, Rahim Kadkhodaie; Rezaee, Reza; Harami, Reza Moussavi;

    2014-01-01

    Tight gas sands in Whicher Range Field of Perth Basin show large heterogeneity in reservoir characteristics and production behavior related to depositional and diagenetic features. Diagenetic events (compaction and cementation) have severely affected the pore system. In order to investigate...

  16. Application of Integrated Reservoir management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    B. Pregger; D. Davies; D. Moore; G. Freeman; J. Callard; J.W. Nevans; L. Doublet; R. Vessell; T. Blasingame

    1997-08-31

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  17. Basic concepts and parallel processing techniques in a cluster of workstations for reservoir rock physical properties determination; Conceitos basicos e tecnicas de processamento paralelo em um cluster de computadores para determinacao de propriedades fisicas de rochas reservatorio

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, A.D. [Universidade Estadual do Norte Fluminense, Macae, RJ (Brazil). Lab. de Engenharia e Exploracao de Petroleo (LENEP)]. E-mail: bueno@lenep.uenf.br

    2003-07-01

    The determination of physical properties of reservoir rocks using image analysis is a reality. The idea of a virtual laboratory where the petrophysics properties are determined with experimental samples and numerical simulations, has demonstrated an important technology in the reduction of the costs and the increase of the speed with that the information are obtained. However, most samples, after the binarization, have a large correlation length, this implies in necessity of large 3D reconstructed image. This remit the developers of models and algorithm's of image analysis of reservoir rocks to use and understand the parallel processing and clusters of workstations. This paper present a brief bibliography revision of the terms and concepts of parallel processing. The different types of parallel processing in multi processed machines are discussed. After this, the used libraries are rapidly presented, multi-processing, multi-threading, and the message passing systems (PVM and MPI). Finally, a study case, comparing the time processing between multiprocessing and multi-threading, in a cluster of 3 nodes, are presented. A set of links and references for external documents are included. (author)

  18. Summary of Research through Phase II/Year 2 of Initially Approved 3 Phase/3 Year Project - Establishing the Relationship between Fracture-Related Dolomite and Primary Rock Fabric on the Distribution of Reservoirs in the Michigan Basin

    Energy Technology Data Exchange (ETDEWEB)

    G. Grammer

    2007-09-30

    This final scientific/technical report covers the first 2 years (Phases I and II of an originally planned 3 Year/3 Phase program). The project was focused on evaluating the relationship between fracture-related dolomite and dolomite constrained by primary rock fabric in the 3 most prolific reservoir intervals in the Michigan Basin. The characterization of select dolomite reservoirs was the major focus of our efforts in Phases I and II of the project. Structural mapping and log analysis in the Dundee (Devonian) and Trenton/Black River (Ordovician) suggest a close spatial relationship among gross dolomite distribution and regional-scale, wrench fault-related NW-SE and NE-SW structural trends. A high temperature origin for much of the dolomite in these 2 studied intervals (based upon fluid inclusion homogenization temperatures and stable isotopic analyses,) coupled with persistent association of this dolomite in reservoirs coincident with wrench fault-related features, is strong evidence for these reservoirs being influenced by hydrothermal dolomitization. In the Niagaran (Silurian), there is a general trend of increasing dolomitization shelfward, with limestone predominant in more basinward positions. A major finding is that facies types, when analyzed at a detailed level, are directly related to reservoir porosity and permeability in these dolomites which increases the predictability of reservoir quality in these units. This pattern is consistent with our original hypothesis of primary facies control on dolomitization and resulting reservoir quality at some level. The identification of distinct and predictable vertical stacking patterns within a hierarchical sequence and cycle framework provides a high degree of confidence at this point that the results should be exportable throughout the basin. Much of the data synthesis and modeling for the project was scheduled to be part of Year 3/Phase III, but the discontinuation of funding after Year 2 precluded those efforts

  19. Estimation on the effective heat extraction area of the reservoir at Hijiori hot dry rock test site; Hijiori kooon gantai ni keisei sareta jinko choryuso no kiretsumen no netsukokan menseki no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Tenma, N.; Matsunaga, I.; Kuriyagawa, M. [National Inst. for Resources and Environment, Tsukuba (Japan); Yamaguchi, T. [New Energy and Industrial Technology Development Organization, Tokyo (Japan); Miyairi, M. [JAPEX Research Center, Tokyo (Japan). Technical Lab.; Zyvoloski, G.

    1994-06-25

    Tests for development of hot dry rock at Hijiori caldera (Yamagata Pref.) started in 1984 and the well SKG-2 (depth: 1,802m, 254{degree}C at well bottom) was dug. In 1986, water pressure crushing being carried out, artificial reservoir was made near the well bottom. On the reservoir, wells HDR-1 (depth: 2,206m), -2 (1,910m) and -3 (1,907m) were dug. In 1991, three month circulation test was conducted using the well SKG-2 as an injection well and other three wells as production ones. Being guessed that there exist several flow paths in the reservoir, a model for investigation was developed for each flow path using the simulation code FEMM. According to the data of temperature and flow rate at every depth (zone) in the production wells, calculations were repeated many times under various conditions. Consequently, positions and heat extraction areas of plural fractures taking part in heat exchange have been estimated. 14 refs., 11 figs., 5 tabs.

  20. Effects of Cementation on Elastic Property and Permeability of Reservoir Rocks%岩石颗粒胶结方式对储层岩石弹性及渗流性质的影响

    Institute of Scientific and Technical Information of China (English)

    赵建鹏; 孙建孟; 姜黎明; 陈惠; 闫国亮

    2014-01-01

    为研究岩石颗粒胶结方式对储层岩石弹性和渗流性质的影响,采用过程模拟法构建了三维数字岩心,在此基础上,分别利用有限元方法和格子玻尔兹曼方法研究了胶结物均匀生长、沿孔隙生长和沿喉道生长3种胶结方式对岩石弹性和渗流特性的影响规律.结果表明:岩石颗粒胶结方式会影响岩石刚性和孔隙连通性,引起岩石弹性模量和渗透率的变化.在相同孔隙度下,胶结物沿喉道生长形成的岩石抗压性最强,渗透率最小;沿孔隙生长形成的岩石抗压性最弱,渗透率最大.3种胶结方式下,岩石弹性模量随着胶结物含量增加而增大,变化率近似相等;岩石渗透率随着胶结物含量的增加而减小,岩石渗透性对颗粒胶结方式的变化更敏感.%In order to investigate the effects of cementation on elastic properties and permeability of reservoir rocks,a 3D digital model of core was constructed.Then this model was simulated using the process-based method and finite element lattice Boltz-mann method.The results show that cementation influences the rock stiffness and pore connectivity,controlling elastic modu-lus and rock permeability,respectively.Given same porosity,rocks with cement occurring in the pore throats have high elastic modulus and low permeability;whereas rocks with cement precipitating within pores have low elastic modulus and high permea-bility.Among the simulated three cementation scenarios,the rock elastic modulus increases with increasing amount of cement, and there is a linear relationship between them.Rock permeability,however,deceases with increasing amount of cement,be-cause permeability is more sensitive to where cements precipitate than rock elastic parameters.

  1. 致密储层岩石的微观结构和力学性质试验分析%The experimental analysis of microstructure and mechanical properties of tight reservoir rocks

    Institute of Scientific and Technical Information of China (English)

    杨海博; 武云云

    2011-01-01

    Under the condition of simulated formation, the mechanical parameters of tight sandstones, taken from certain middle Sichuan gasfield and Sulige gasfield, are measured by a static (dynamical) triaxial rock mechanics test system, RTR- 1000 model,which was manufactured by the American GCTS corporation, to obtain the elastic modules, Poisson' s ratio and compressive strength. Using analysis of microscopic fabric of rocks, and combining with rock mechanical testes, the factors, influencing the mechanical characters of rocks, are discussed, to provide some basic parameters for the study of rock mechanical properties of similar reservoirs.%以致密砂岩为研究对象,利用美国GCTS公司研制的RTR-1000型静(动)三轴岩石力学测试系统对川中某气田和苏里格气田储层致密砂岩进行了模拟地层条件的岩石力学性质测试,获得了致密砂岩在储层条件下的弹性模量、泊松比和抗压强度等岩石力学参数。采用岩石显微组构分析和岩石力学试验相结合的方法,探讨影响岩石力学性质的因素,为该类型储层条件下岩石力学性质的研究提供了一些基本参数。

  2. The Importance of Geochemical Parameters and Shale Composition on Rock Mechanical Properties of Gas Shale Reservoirs: a Case Study From the Kockatea Shale and Carynginia Formation From the Perth Basin, Western Australia

    Science.gov (United States)

    Labani, Mohammad Mahdi; Rezaee, Reza

    2015-05-01

    Evaluation of the gas shale mechanical properties is very important screening criteria for determining the potential intervals for hydraulic fracturing and as a result in gas shale sweet spot mapping. Young's modulus and Poisson's ratio are two controlling mechanical properties that dictate the brittleness of the gas shale layers. These parameters can be determined in the laboratory by testing the rock sample under different conditions (static method) or can be calculated using the well-logging data including sonic and density log data (dynamic method). This study investigates the importance of the shale composition and geochemical parameters on the Young's modulus and Poisson's ratio using log data. The data set of this study is coming from five different wells targeting the Kockatea Shale and Carynginia formation, two potential gas shale formations in the Perth Basin, Western Australia. The results show that converse to the common idea the effect of organic matter quantity and maturity on the rock mechanical properties of the gas shale reservoirs is not so much prominent, while the composition of the rock has an important effect on these properties. Considering the weight percentage of shale composition and organic matter quantity it could be concluded that effect of these parameters on rock mechanical properties is dependent on their weight contribution on the shale matrix. As well as effect of thermal maturity on the shale matrix and consequently on the rock mechanical properties of the shales is dependent on the organic matter content itself; therefore, obviously with a low organic matter content thermal maturity has no prominent effect on the brittleness as well.

  3. Reconstruction of sedimentary environments of J2-4 reservoir rocks of the Lovin oil field by facial analysis and 3D simulation

    Science.gov (United States)

    Iagudin, R.; Minibaev, N.

    2012-04-01

    The reconstruction of accumulations' conditions of sand bodies and determination of paleogeographical conditions is the basis for 3D modeling of lithologically screened oil and gas reservoirs. The reconstruction of accumulations' conditions is implemented by lithologic-and-facies analysis. The facial types are determined during the analysis of deposits of oil reservoir and then mapped within the reservoir's space. The facies type is an integral characteristic. It is determined on the basis of a large number of research methods such as the processing and analysis of core samples, seismic and well log data. Mapping of reservoirs' facies types allow estimating variability of important for exploration of oil deposits parameters such as reservoir properties, productivity, distribution of effective thickness, etc. The facies types can be mapped as an individual geological unit and used in 3D geological modeling. Subject of facial analysis was sediments of J2-4 reservoir of Lovin oil field (Western Lovin structure) which were accumulated in the Jurassic period. Based on lithologic-and-facies analysis of core material from 6 wells (25 samples), including studies on the grain size measurements, analysis of sediment's structure and core description, the metering of magnetic susceptibility of sediments, facies types of the J2-4 reservoir were identified. The lithotype A is characterized by sand and silt structure, small nodules in the halo of pyrite oxidation, indicated the presence of magnetite. This lithotype belongs to conditions of river-bed facies. The lithotype B have a silty structure, interlayer of coal and traces of bioturbation. This lithotype corresponds to the conditions of sand bars of the floodplain. The lithotype C is characterized by silty-clay structure, single siderite nodules and the remnants of the fauna. This is referring to bog part of the floodplain. After analyzing the well log data of 25 wells of Lovin oil field by Muromtsev methodology distribution

  4. 岩石结构对碎屑岩储层弹性参数影响的数值研究%Numerical study of the effect of rock texture on the clastic reservoir rocks’ elastic parameters

    Institute of Scientific and Technical Information of China (English)

    章海宁; 姜黎明; 张金功; 孙建孟; 屈乐; 樊云峰

    2014-01-01

    3-D digital cores were constructed using the process-based method with the grain size distribution of the rock. The effects of grain size ratio, grain size and grain sorting on the elastic properties of the clastic reservoir rocks were studied using the finite element method based on the digital cores. The results showed that the grain size and grain sorting have notable effect on rock physics properties and pore structure, which will cause the variations in elastic moduli and velocities. The relation between the grain size ratio and the elastic properties of the clastic reservoir rocks is non-linear. The bulk modulus increases until it reaches a maximum value, and then decreases to tend to a constant with increasing volume fraction of large grains. The effect of volume fraction of large grains on the elastic moduli strengthens as the grain size ratio increases. The effect of the grain size on the elastic properties of water-saturated rock is weaker than that of dry rock. Moreover, the bulk moduli is more sensitive to fluid changes when the grain size is very small. The worse the sorting is, the greater the elastic moduli and velocities of clastic reservoir rocks will be.%结合岩石颗粒粒径分布,通过过程模拟法构建3维数字岩心,利用有限元方法研究了岩石颗粒尺寸比、颗粒大小以及颗粒分选性对岩石弹性特性的影响。结果表明岩石颗粒的大小、分选性均会对岩石的物性以及孔隙结构产生影响,引起岩石弹性模量和纵横波速度的变化。颗粒尺寸比对岩石弹性的影响是非线性的,随着大颗粒含量的增大,岩石体积模量先增大至最大值,然后再减小至趋于不变,随着颗粒尺寸比的变大,大颗粒含量对岩石弹性模量的影响增强。粒径对饱和水岩石弹性的影响弱于对干岩石的,并且粒径越小,岩石体积模量对孔隙流体的变化越敏感。随颗粒分选性变差,岩石体积模量和剪切模量及纵横波速度变大。

  5. Geochemical modeling of water-gas-rock interactions. Application to mineral diagenesis in geologic reservoirs; Modelisation geochimique des interactions eau-gaz-roche. Application a la diagenese minerale dans les reservoirs geologiques

    Energy Technology Data Exchange (ETDEWEB)

    Bildstein, O.

    1998-03-13

    The Ph.D. report describes a conceptual and numerical model for simulating gas-water-rock interaction during mineral diagenesis of sediments. The main specific features of this model are the following: applicable to open systems, half-implicit resolution numerical method, feedback on the texture evolution (grain model), existence of a gas phase, oxido-reduction phenomena. (author) 217 refs.

  6. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    Energy Technology Data Exchange (ETDEWEB)

    Wopat, M A; Curry, W E; Robins, J W; Marjaniemi, D K

    1977-10-01

    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins.

  7. Numerical Study of the Effect of Natural Gas Saturation on the Reservoir Rocks' Elastic Parameters%天然气饱和度对岩石弹性参数影响的数值研究

    Institute of Scientific and Technical Information of China (English)

    姜黎明; 孙建孟; 刘学锋; 王海涛

    2012-01-01

    The variation law of the effect of natural gas saturation on the reservoir rocks' elastic parameters, such as elastic moduli, P-wave and S-wave velocities, Lame constant, Poisson's ratio, is studied based on 3D digital cores. The results show that gas saturation of reservoir rocks has little influence on S-wave velocity and the S-wave velocity increases slowly with the increase of gas saturation. The elastic parameters, such as Lame constant, Poisson's ratio, P-wave velocity, the ratio of P-wave velocity to S-wave velocity, decrease as the gas saturation increases, Moreover, they are changed sharply when the sandstone contains very small amount of gas. After comparing the change ratios of the elastic parameters with the variation of gas saturation, it is found the Lame constant is most sensitive to the variation of gas saturation, followed by Poisson's ratio, bulk modulus and the ratio of P-wave velocity to S-wave velocity. Through this study, the parameter which is sensitive to change of gas saturation can be used to calculate gas saturation of reservoir rocks in order to improve the calculation accuracy.%基于三维数字岩心,对岩石的弹性模量、纵横波速度、拉梅常数、泊松比等参数随不同含气饱和度变化规律进行数值研究.研究结果表明岩石的含气饱和度对横波速度影响不大,含气饱和度的增加将引起横波速度的缓慢增加.岩石的拉梅常数、泊松比、纵波速度、弹性模量和纵横波速度比随含气饱和度的增加而减小,当含气饱和度较低时,它们随含气饱和度增加急剧降低.将各弹性参数随含气饱和度的变化率进行比较,发现对天然气饱和度变化最敏感的参数是拉梅常数,其次是泊松比、体积模量和纵横波速度比等.该研究有助于选取对天然气饱和度变化敏感的参数计算储层的含气饱和度,从而提高计算精度.

  8. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L. [BDM-Petroleum Technologies, Bartlesville, OK (United States); Young, M.A.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)] [and others

    1997-08-01

    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  9. Preliminary design study of underground pumped hydro and compressed-air energy storage in hard rock. Volume 8: Design approaches. UPH. Appendix E: Lower reservoir

    Science.gov (United States)

    1981-04-01

    Operational, construction, and geotechnical requirements were examined. Overriding considerations including operating range, volume, construction methods, cavern cross section and reservoir layout were studied within the context of minimizing facility costs and optimizing the plant layout. The study led to a preliminary arrangement of fourteen parallel caverns, each 60 ft wide by 85 ft high in cross section and 3610 ft in length. The requirements for and preliminary design of the intermediate reservoir in the case of a two step UPH facility is also described. The design and the cost estimates presented are based on the requirements for a 2000 MW plant providing 20,000 MWh of storage at a nominal head of 4600 ft.

  10. 煤岩储气层岩石蠕变特性与本构模型研究%RESEARCH ON CREEP PROPERTY AND CONSTITUTIVE MODEL OF ROCK IN COAL BED GAS RESERVOIR

    Institute of Scientific and Technical Information of China (English)

    范翔宇; 张千贵; 艾巍; 夏宏泉; 何传亮; 李枝林

    2013-01-01

    与一般煤岩相比,裂隙发育是煤岩储气层的主要物理特征,其结构较为软弱,在复杂地应力条件下易产生蠕变破坏,往往造成煤层气开采中钻井的破坏失稳。为探讨储气层煤岩钻井壁的蠕变失稳规律,采用美国RT R-1000型三轴岩石力学测试系统对储气层煤岩进行系统的单轴压缩试验。利用饱依丁-汤姆逊体与宾汉姆体,建立储气层煤岩蠕变模型,并通过拟合得到蠕变方程中的各个参数。根据储气层煤岩在不同载荷条件下的单轴压缩试验结果对蠕变模型进行验证。结果表明,所提出的储气层煤岩蠕变模型能很好地描述各蠕变阶段的变形特性,尤其是衰减阶段与稳定蠕变阶段,并能很好地反映蠕变的长期强度。同时,将煤岩蠕变特性与钻井方式相结合,提出煤层钻井液的优选思路,对保持煤岩钻井壁稳定、有效保护储集层以及高效安全建井等具有重要的实际意义。%Compared with normal coal,fracture development is the main physical characteristics of coal in coal bed gas reservoir,its structure is very complicated,and its easy to be damaged under geostress,always leads to the failure and instability of drilling during the exploitation process of coal bed gas. In order to explore the law of creep instability of borehole wall in coal bed gas reservoir,the writer adopted the American RTR-1000 triaxial rock mechanical test system to test the uniaxial creep law of coal in coal bed gas reservoir. Combined the Poyting-Thomson model with Bingham model,a creep model of coal is builted in coal bed gas reservoir and each parameter of creep equation through fitting is achieved. The creep model has been verified according to the uniaxial creep test results of coal in coal bed gas reservoir under different load conditions. The results show that the creep model of coal in coal bed gas reservoir can describe the deformation properties of each creep

  11. Determination of paleo-pressure for a natural gas pool formation based on PVT characteristics of fluid inclusions in reservoir rocks--A case study of Upper-Paleozoic deep basin gas trap of the Ordos Basin

    Institute of Scientific and Technical Information of China (English)

    MI Jingkui; XIAO Xianming; LIU Dehan; SHEN Jiagui

    2004-01-01

    It has been proved to be a difficult problem to determine directly trapping pressure of fluid inclusions. Recently, PVT simulation softwares have been applied to simulating the trapping pressure of petroleum inclusions in reservoir rocks, but the reported methods have many limitations in practice. In this paper, a method is suggested to calculating the trapping pressure and temperature of fluid inclusions by combining the isochore equations of a gas-bearing aqueous inclusion with its coeval petroleum inclusions. A case study was conducted by this method for fluid inclusions occurring in the Upper-Paleozoic Shanxi Formation reservoir sandstones from the Ordos Basin. The results show that the trapping pressure of these inclusions ranges from 21 to 32 MPa, which is 6-7 MPa higher than their minimum trapping pressure although the trapping temperature is only 2-3℃ higher than the homogenization temperature. The trapping pressure and temperature of the fluid inclusions decrease from southern area to northern area of the basin.The trapping pressure is obviously lower than the state water pressures when the inclusions formed. These data are consistent with the regional geological and geochemical conditions of the basin when the deep basin gas trap formed.

  12. Composite microstructural anisotropies in reservoir rocks: consequences on elastic properties and relation with deformation; Anisotropies microstructurales composites dans les roches reservoir: consequences sur les proprietes elastiques et relation a la deformation

    Energy Technology Data Exchange (ETDEWEB)

    Louis, L.

    2003-10-15

    From diagenesis to tectonic stress induced deformation, rock microstructures always present some anisotropy associated with a preferential orientation, shape or spatial arrangement of its constituents. Considering the consequences anisotropy has on directional transport properties and compliance, as the geological history it carries, this approach has received a particular attention in numerous works. In this work, the microstructural features of various sedimentary rocks were investigated through direct observations and laboratory measurements in naturally deformed and undeformed blocks, samples being considered as effective media. All investigated samples were found to be anisotropic with respect to the physical properties we measured (i.e. ultrasonic P-wave velocity, magnetic susceptibility, electrical conductivity). Considering that P-wave velocities can be described by a second order tensor, we applied to the velocity data the same inversion procedure as the one routinely used in magnetic studies, which provided an efficient tool to estimate and compare these 3D anisotropies with respect to the original sample geographical position. In each case, we tried to identify as thoroughly as possible the microstructural source of the observed anisotropies, first by the mean of existing models, then through direct observations (optic and electronic microscopy). Depending on the rock investigated, anisotropy was found to be controlled by pore shape, intergranular contact distribution, preferentially oriented microcracks interacting with compaction pattern or pressure solution cleavages interacting with each other. The net result of this work is that P-wave velocity anisotropy can express the interaction between different microstructural features as well as their evolution during deformation. (author)

  13. In a reservoir rock landslide dynamic load response analysis%某水库新岩滑坡动荷载响应分析

    Institute of Scientific and Technical Information of China (English)

    张颖

    2016-01-01

    以在建某水库上的新岩滑坡为例,借助GeoStudio软件中的部分软件模块,探究了地震与交通震动荷载对滑坡的影响。%With the help of GeoStudio, a discussion about the influence over the landslide of earthquake and traffic vibra-tion load is made based on the XinYan landslide on one reservoir.

  14. Reservoir resistivity characterization incorporating flow dynamics

    KAUST Repository

    Arango, Santiago

    2016-04-07

    Systems and methods for reservoir resistivity characterization are provided, in various aspects, an integrated framework for the estimation of Archie\\'s parameters for a strongly heterogeneous reservoir utilizing the dynamics of the reservoir are provided. The framework can encompass a Bayesian estimation/inversion method for estimating the reservoir parameters, integrating production and time lapse formation conductivity data to achieve a better understanding of the subsurface rock conductivity properties and hence improve water saturation imaging.

  15. Visualisation des propriétés capillaires des roches réservoir Visualizing the Capillary Properties of Reservoir Rocks

    Directory of Open Access Journals (Sweden)

    Zinszner B.

    2006-11-01

    Full Text Available Cet article décrit des expériences de drainage par centrifugation et d'imbibition par ascension capillaire réalisées avec des résines époxy colorées. Après polymérisation, l'observation des lames minces permet de localiser les fluides mouillants et non mouillants. Après avoir décrit les modes opératoires en insistant sur l'analyse des paramètres expérimentaux, on donne des exemples d'applications à la géologie de réservoir. Deux points sont développés : les études de perméabilités et les modèles de réservoir qui permettent d'étudier la répartition du fluide mouillant et des fractions déplaçables ou piégées du fluide non mouillant. This article describes drainage experiments by centrifuge method and imbibition by capillary rise performed with colored epoxy resins. After polymerization, analysis of thin sections serves to situate the wetting and nonwetting fluids. After describing the operating methods with em-phasis on the analysis of experimental parameters, the article gives examples of applications to reservoir geology. The following two points are developed : (i permeability investigations and (ii reservoir modelswhich can be used to analyze the distribution of the wetting fluid and the movable or trapped fractions of the nonwetting fluid

  16. Three-dimensional analysis of a faulted CO2 reservoir using an Eshelby-Mori-Tanaka approach to rock elastic properties and fault permeability

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Ba Nghiep; Hou, Zhangshuan; Last, George V.; Bacon, Diana H.

    2016-12-01

    This work develops a three-dimensional multiscale model to analyze a complex CO2 faulted reservoir that includes some key geological features of the San Andreas and nearby faults southwest of the Kimberlina site. The model uses the STOMP-CO2 code for flow modeling that is coupled to the ABAQUS® finite element package for geomechanical analysis. A 3D ABAQUS® finite element model is developed that contains a large number of 3D solid elements with two nearly parallel faults whose damage zones and cores are discretized using the same continuum elements. Five zones with different mineral compositions are considered: shale, sandstone, fault damaged sandstone, fault damaged shale, and fault core. Rocks’ elastic properties that govern their poroelastic behavior are modeled by an Eshelby-Mori-Tanka approach (EMTA). EMTA can account for up to 15 mineral phases. The permeability of fault damage zones affected by crack density and orientations is also predicted by an EMTA formulation. A STOMP-CO2 grid that exactly maps the ABAQUS® finite element model is built for coupled hydro-mechanical analyses. Simulations of the reservoir assuming three different crack pattern situations (including crack volume fraction and orientation) for the fault damage zones are performed to predict the potential leakage of CO2 due to cracks that enhance the permeability of the fault damage zones. The results illustrate the important effect of the crack orientation on fault permeability that can lead to substantial leakage along the fault attained by the expansion of the CO2 plume. Potential hydraulic fracture and the tendency for the faults to slip are also examined and discussed in terms of stress distributions and geomechanical properties.

  17. Transport and Deposition of Nanoparticles in the Pore Network of a Reservoir Rock: Effects of Pore Surface Heterogeneity and Radial Diffusion

    Science.gov (United States)

    Pham, Ngoc; Papavassiliou, Dimitrios

    2014-03-01

    In this study, transport behavior of nanoparticles under different pore surface conditions of consolidated Berea sandstone is numerically investigated. Micro-CT scanning technique is applied to obtain 3D grayscale images of the rock sample geometry. Quantitative characterization, which is based on image analysis is done to obtain physical properties of the pore network, such as the pore size distribution and the type of each pore (dead-end, isolated, and fully connected pore). Transport of water through the rock is simulated by employing a 3D lattice Boltzmann method. The trajectories of nanopaticles moving under convection in the simulated flow field and due to molecular diffusion are monitored in the Lagrangian framework. It is assumed in the model that the particle adsorption on the pore surface, which is modeled as a pseudo-first order adsorption, is the only factor hindering particle propagation. The effect of pore surface heterogeneity to the particle breakthrough is considered, and the role of particle radial diffusion is also addressed in details. The financial support of the Advanced Energy Consortium (AEC BEG08-022) and the computational support of XSEDE (CTS090017) are acknowledged.

  18. 三峡库区黄土坡临江滑坡体水岩(土)相互作用机理%Water-rock (soil) interaction mechanism of Huangtupo riverside landslide in Three Gorges Reservoir

    Institute of Scientific and Technical Information of China (English)

    江洎洧; 项伟; 曾雯; JOACHIM Rohn; 姚远

    2012-01-01

    水岩(土)相互作用与滑坡地质灾害的形成密切相关。选取仍处于变形阶段的三峡库区黄土坡临江滑坡体为研究对象,以从滑坡不同部位采集的8类滑坡不良地质体(包括滑带土、软弱层、软岩等)为研究样本,追踪测试各样本的矿物类型及含量、化学组分及颗粒级配等指标。经分析,各类不良地质体之间具有明显的同源性特征,在水岩(土)相互作用下,主要滑坡不良地质体的成因及转化过程得以清晰呈现。随后,另取主滑带附近垂直方向上的岩土体样本为例,结合试验数据,深入分析并直观展现了水岩(土)相互作用对岩土体微观结构和力学性能弱化的影响。本研究深入探讨了黄土坡临江滑坡体中的水岩(土)相互作用机理,研究成果对于了解相似滑坡灾害的形成过程和有针对性制定滑坡防治方案具有重要参考价值。%The water-rock (soil) interaction is closely related to the formation of landslides hazards. Huangtupo riverside landslide, which locates in the district of Three Gorges Reservoir, and is still in the process of intense deformation, is chosen as the research landslide. 8 kinds of unfavorable geologic bodies (including soft rock layer, sliding soil and weak intercalation) are collected from different parts of the landslide, and these samples are employed to track and test the mineral type and content, chemical composition and particle size distribution and other indicators. After analysis, 8 kinds of unfavorable geologic bodies have an obvious homeology; and in the water-rock (soil) interaction, the formation and transformation processes of the main unfavorable geologic elements can be clearly presented. Afterward, based on a number of rock and soil samples collected near the main slip zone along the vertical direction and combined with test data, in-depth analysis and visual display of how the water-rock

  19. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    Science.gov (United States)

    Nurhandoko, Bagus Endar B.; Susilowati

    2015-04-01

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir's layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir's character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia.

  20. Role of Oxalis corniculata L. as plant virus reservoir with special regard to Tomato Spotted Wilt Virus (TSWV-RB strain occurrence in rock-wool cultivation in Hungary

    Directory of Open Access Journals (Sweden)

    Hodi, Anna Maria

    2014-02-01

    Full Text Available The creeping wood sorrel (Oxalis corniculata L. in Central Europe occurs mainly in anthropogenic areas, where it grows in parks and landfill sites or in protected cultivation sites like greenhouses and nurseries. In Hungary O. corniculata has been spreading since the 19th century. In glass- and greenhouses it is the only weed species that was able to settle and flourish on hydroponic rock-wool and coconut fibre growing media. Among virus pathogens of forced tomato (LYPES and paprika crops (CPSAN in Hungary the Tomato Spotted Wilt Virus (TSWV has become an important one, severely affecting the plants and on occasions causing 100% yield losses. The spread of the virus was largely assisted by its effective vector the Western Flower Thrips (Frankliniella occidentalis Pergande. Initially the control of the disease was based on the control of the thrips, later, virus-resistant varieties were introduced. This however proved insufficient to fight the disease as it was discovered, quite recently, that in certain white pepper (CPSAN varieties the virus was able to break up the resistance. According to data of the year 2012, those varieties that were considered resistant, showed up to 50% virus infection. Considering the wide spread of O. corniculata and increasing occurrence of the resistance-breaking TSWV isolates, surveys in greenhouses were conducted to examine whether the weed could serve as reservoir for TSWV. Samples were collected of the virus infected crop plants and O. corniculata growing in the same coconut fibre cubes. The samples were examined using test-plants, serological and RT-PCR methods. In result it was found that the symptoms were indeed caused by resistance-breaking TSWV isolates. However, no virus was found in the suspected O. corniculata samples. Therefore it was concluded that in this particular case the O. corniculata cannot be considered reservoir for the virus, in the hydroponic culture.

  1. Mathematical Simulation on Induced Polarization of Reservoir Rock in Time Domain%储层岩石时间域激发极化效应的数学模拟

    Institute of Scientific and Technical Information of China (English)

    关继腾; 于华; 王谦; 范业活; 程媛媛

    2012-01-01

    Based on a microscope capillary model, a mathematical model for induced polarization of reservoir rock is obtained. Influences of concentration difference polarization and electric double-layer deformation on induced polarizability are studied numerically. It shows that induced polarization is governed by ion concentration difference polarization in capillary. Electric double-layer deformation has greater influence on total polarizability. Speed of charging and discharging in induced polarization depends mainly on cation exchange capacity and pore structure of rock.%以储层岩石的串联毛管模型为基础,建立描述含水储层岩石时间域激发极化效应的数学模型.数值模拟储层岩石孔隙中离子的浓差极化效应和双电层形变效应.孔隙中浓差极化控制着激发极化随时间的变化,双电层形变不控制激发极化随时间的变化.浓差极化效应对激发极化极化率的贡献较小,双电层形变效应对激发极化极化率的贡献较大.激发极化充放电过程的快慢,主要取决于固液界面阳离子的吸附能力和岩石的孔隙结构.

  2. Reservoir geomechanics: new approach to reservoir engineering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Settari, A.; Walters, D.A.; Behie, G.A. [Duke Engineering and Services Inc., Calgary, AB (Canada)

    1999-07-01

    The rock mechanics aspects of reservoir behavior are reviewed, and a description is included of some recent trends in coupled reservoir and strata mechanics modelling. Case histories are summarized which are field applications of these new trends and tools. These case histories include: (1) high rate injection into an oil sand reservoir; (2) compaction modelling of a North Sea reservoir; and (3) brine disposal at a fracturing pressure. Coupled geomechanical modelling is feasible on a full field scale, and it provides flexibility in the degree of coupling and calculational efficiency. The scope of interest in data gathering and characterization must be extended beyond reservoir boundaries because of the coupled modelling approach. This modelling provides results that can be employed in integrated reservoir management that includes reservoir engineering, drilling and completions. Considering the three case histories, coupled modelling can be used for predicting fracture initiation and re-orientation, reservoir compaction and deformations, and enhancement of injectivity due to stress dependent formation properties. Coupled modelling has brought reservoir modelling to a new realistic level and produces significant economic gains. 15 refs., 8 figs.

  3. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Goethermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equiptment

    Energy Technology Data Exchange (ETDEWEB)

    Nancy Moller Weare

    2006-07-25

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  4. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nurhandoko, Bagus Endar B., E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4" t" hfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia); Susilowati, E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Rock Fluid Imaging Lab., Bandung (Indonesia)

    2015-04-16

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia.

  5. Time-lapse seismic within reservoir engineering

    OpenAIRE

    Oldenziel, T.

    2003-01-01

    Time-lapse 3D seismic is a fairly new technology allowing dynamic reservoir characterisation in a true volumetric sense. By investigating the differences between multiple seismic surveys, valuable information about changes in the oil/gas reservoir state can be captured. Its interpretation involves different disciplines, of which the main three are: reservoir management, rock physics, and seismics. The main challenge is expressed as "How to optimally benefit from time-lapse seismic". The chall...

  6. Controlling of Hydrocarbons Expulsion of Source Rock on Buried Hill Hydrocarbon Reservoir in Nanpu Depression by Acoustic Logging Methodology%测井-地化结合法探讨南堡凹陷潜山源控藏作用

    Institute of Scientific and Technical Information of China (English)

    董月霞; 李素梅; 陈安定; 王政军; 张鹏; 陈君

    2015-01-01

    Industrial petroleum was discovered from Palaeozoic deep horizons in the Nanpu Depression,Bohai Bay Basin,which suggests significant deep petroleum potential in the area.One of the issues in exploration is forecasting favorable place for prospecting in the area.Hydrocarbons expulsion downward from the source rocks immediately overlapped buried hill should be useful in this aspect.Acoustic logging combined with geochemical approaches was utilized in this study to identify hydrocarbons expulsion and evaluate hydrocarbon potential.Af-ter a detailed correlative acoustic logging and geochemical study,a combined hydrocarbons expulsion model of the source rocks in the Nanpu Depression was established,which was used to investigate hydrocarbons expulsion of the source rocks from 33 wells in the Nanpu Depression.The results suggest that the average depths of the source rocks with the hydrocarbons expelled downward into the burial hill in the No.2 and 3 Tectonic Belts are about 248 m and 358 m,respectively,and only 35 m for the No.1 Tectonic Belt.No obvious hydrocarbons ex-pulsion into burial hill was observed in the No.4 and 5 Tectonic Belts in the depression.This result coincides with the hydrocarbons discovered up to now in the burial hills.We suggest that these factors including contact style between the source rock and the burial hill,the position of the hydrocarbon kitchen,the thermal maturity of the source rocks,the volcanic rock acting as barrier bed and faults developed,have a controlling of the amounts and characteristics of the hydrocarbons expelled by the source rocks and charged into the burial hill in the Nanpu Depression.A comprehensive study of hydrocarbons expulsion,migration and accumulation indicate that the No.2 and 3 Tectonic Belts and next the No.1 Tectonic Belt are prospective areas with burial hill hydro-carbons reservoir developed.This study also indicated that acoustic logging could be an important tool identif-ying hydrocarbons expulsion and would

  7. Reservoir characteristics and control factors of Carboniferous volcanic gas reservoirs in the Dixi area of Junggar Basin, China

    Directory of Open Access Journals (Sweden)

    Ji'an Shi

    2017-02-01

    Full Text Available Field outcrop observation, drilling core description, thin-section analysis, SEM analysis, and geochemistry, indicate that Dixi area of Carboniferous volcanic rock gas reservoir belongs to the volcanic rock oil reservoir of the authigenic gas reservoir. The source rocks make contact with volcanic rock reservoir directly or by fault, and having the characteristics of near source accumulation. The volcanic rock reservoir rocks mainly consist of acidic rhyolite and dacite, intermediate andesite, basic basalt and volcanic breccia: (1 Acidic rhyolite and dacite reservoirs are developed in the middle-lower part of the structure, have suffered strong denudation effect, and the secondary pores have formed in the weathering and tectonic burial stages, but primary pores are not developed within the early diagenesis stage. Average porosity is only at 8%, and the maximum porosity is at 13.5%, with oil and gas accumulation showing poor performance. (2 Intermediate andesite and basic basalt reservoirs are mainly distributed near the crater, which resembles the size of and suggests a volcanic eruption. Primary pores are formed in the early diagenetic stage, secondary pores developed in weathering and erosion transformation stage, and secondary fractures formed in the tectonic burial stage. The average porosity is at 9.2%, and the maximum porosity is at 21.9%: it is of the high-quality reservoir types in Dixi area. (3 The volcanic breccia reservoir has the same diagenetic features with sedimentary rocks, but also has the same mineral composition with volcanic rock; rigid components can keep the primary porosity without being affected by compaction during the burial process. At the same time, the brittleness of volcanic breccia reservoir makes it easily fracture under the stress; internal fracture was developmental. Volcanic breccia developed in the structural high part and suffered a long-term leaching effect. The original pore-fracture combination also made

  8. A finite element simulation system in reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Xiaozhong [Louisiana State Univ., Baton Rouge, LA (United States)

    1996-03-01

    Reservoir engineering is performed to predict the future performance of a reservoir based on its current state and past performance and to explore other methods for increasing the recovery of hydrocarbons from a reservoir. Reservoir simulations are routinely used for these purposes. A reservoir simulator is a sophisticated computer program which solves a system of partial differential equations describing multiphase fluid flow (oil, water, and gas) in a porous reservoir rock. This document describes the use of a reservoir simulator version of BOAST which was developed by the National Institute for Petroleum and Energy Research in July, 1991.

  9. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  10. A reservoir simulation approach for modeling of naturally fractured reservoirs

    Directory of Open Access Journals (Sweden)

    H. Mohammadi

    2012-12-01

    Full Text Available In this investigation, the Warren and Root model proposed for the simulation of naturally fractured reservoir was improved. A reservoir simulation approach was used to develop a 2D model of a synthetic oil reservoir. Main rock properties of each gridblock were defined for two different types of gridblocks called matrix and fracture gridblocks. These two gridblocks were different in porosity and permeability values which were higher for fracture gridblocks compared to the matrix gridblocks. This model was solved using the implicit finite difference method. Results showed an improvement in the Warren and Root model especially in region 2 of the semilog plot of pressure drop versus time, which indicated a linear transition zone with no inflection point as predicted by other investigators. Effects of fracture spacing, fracture permeability, fracture porosity, matrix permeability and matrix porosity on the behavior of a typical naturally fractured reservoir were also presented.

  11. Understanding the True Strimulated Reservoir Volume in Shale Reservoirs

    KAUST Repository

    Hussain, Maaruf

    2017-06-06

    Successful exploitation of shale reservoirs largely depends on the effectiveness of hydraulic fracturing stimulation program. Favorable results have been attributed to intersection and reactivation of pre-existing fractures by hydraulically-induced fractures that connect the wellbore to a larger fracture surface area within the reservoir rock volume. Thus, accurate estimation of the stimulated reservoir volume (SRV) becomes critical for the reservoir performance simulation and production analysis. Micro-seismic events (MS) have been commonly used as a proxy to map out the SRV geometry, which could be erroneous because not all MS events are related to hydraulic fracture propagation. The case studies discussed here utilized a fully 3-D simulation approach to estimate the SRV. The simulation approach presented in this paper takes into account the real-time changes in the reservoir\\'s geomechanics as a function of fluid pressures. It is consisted of four separate coupled modules: geomechanics, hydrodynamics, a geomechanical joint model for interfacial resolution, and an adaptive re-meshing. Reservoir stress condition, rock mechanical properties, and injected fluid pressure dictate how fracture elements could open or slide. Critical stress intensity factor was used as a fracture criterion governing the generation of new fractures or propagation of existing fractures and their directions. Our simulations were run on a Cray XC-40 HPC system. The studies outcomes proved the approach of using MS data as a proxy for SRV to be significantly flawed. Many of the observed stimulated natural fractures are stress related and very few that are closer to the injection field are connected. The situation is worsened in a highly laminated shale reservoir as the hydraulic fracture propagation is significantly hampered. High contrast in the in-situ stresses related strike-slip developed thereby shortens the extent of SRV. However, far field nature fractures that were not connected to

  12. On a model simulating lack of hydraulic connection between a man-made reservoir and the volume of poroelastic rock hosting the focus of a post-impoundment earthquake

    Science.gov (United States)

    Chander, Ramesh; Tomar, S. K.

    2016-12-01

    The idea that a direct hydraulic connection between a man-made reservoir and the foci of post-impoundment earthquakes may not exist at all sites is eminently credible on geological grounds. Our aim is to provide a simple earth model and related theory for use during investigations of earthquakes near new man-made reservoirs. We consider a uniform circular reservoir which rests on the top surface of a no-hydraulic-connection earth model (NHCEM). The model comprises a top elastic (E) layer, an intermediate poroelastic (P) layer, and a bottom elastic half space. The focus of a potential earthquake in the P layer is located directly under the reservoir. The E layer disrupts the hydraulic connection between the reservoir and the focus. Depth of water in the reservoir varies as H ' + hcos( ω t). Expressions for reservoir-induced stresses and pore pressure in different layers of the NHCEM are obtained by solving the boundary-value problem invoking full coupling between mean normal stress and pore pressure in the P layer. As an application of the derived mathematical results, we have examined and found that earthquakes on 60∘ normal faults may occur in the P-layer of a selected NHCEM at epochs of low reservoir level if the reservoir lies mostly in the footwall of the fault. The exercise was motivated by observations of such earthquakes under the man-made Lake Mead after it was impounded.

  13. On a model simulating lack of hydraulic connection between a man-made reservoir and the volume of poroelastic rock hosting the focus of a post-impoundment earthquake

    Indian Academy of Sciences (India)

    Ramesh Chander; S K Tomar

    2016-12-01

    The idea that a direct hydraulic connection between a man-made reservoir and the foci of postimpoundment earthquakes may not exist at all sites is eminently credible on geological grounds. Our aim is to provide a simple earth model and related theory for use during investigations of earthquakes near new man-made reservoirs. We consider a uniform circular reservoir which rests on the top surface of a no-hydraulic-connection earth model (NHCEM). The model comprises a top elastic (E) layer, an intermediate poroelastic (P) layer, and a bottom elastic half space. The focus of a potential earthquake in the P layer is located directly under the reservoir. The E layer disrupts the hydraulic connection between the reservoir and the focus. Depth of water in the reservoir varies as H'+h cos(ωt). Expressions for reservoir-induced stresses and pore pressure in different layers of the NHCEM are obtained by solving the boundary-value problem invoking full coupling between mean normal stress and pore pressure in the P layer. As an application of the derived mathematical results, we have examined and found that earthquakes on 60° normal faults may occur in the P-layer of a selected NHCEM at epochs of low reservoir level if the reservoir lies mostly in the footwall of the fault. The exercise was motivated by observations of such earthquakes under the man-made Lake Mead after it was impounded

  14. 致密火山岩物性影响因素分析与储层质量预测--以马朗-条湖凹陷条湖组为例%Controlling factors on physical property of tight volcanic rocks and reservoir quality prediction:a case study of the Tiaohu Formation in Marlang-Tiaohu Sag

    Institute of Scientific and Technical Information of China (English)

    孟元林; 胡越; 李新宁; 胡安文; 吴晨亮; 赵紫桐; 张磊; 许丞

    2014-01-01

    Commercial oil flows were tested in the tight vitric and crystal sedimentary tuff reservoirs of the 2nd Member of Tiaohu Formation(P2t2)in Malang-Tiaohu Sag,Santanghu Basin.In order to reveal the distribution pattern of tight oil ,we studied the influences of lithofacies and diagenesis on physical properties of volcanic reservoirs .And plane distribution of four types tight reservoir of P 2 t2 were predicted through numerical modeling of diagenesis and in combination with lithofa -cies map.The results show that the quality volcanic reservoir decreases with increasing levels of diagenesis ;Pyroclastic rock and tuff are optimal reservoirs ,followed by vitric and crystal sedimentary tuffs and pyroclastic rocks ,and lavas show the worst reservoir property .The conventional reservoirs ( porosity≥9%) distribute in the southern Malang-Tiaohu Sag , and slight tight reservoirs ( 7%≤porosity <9%) and strong tight reservoirs ( ( 4%≤porosity <7%) are located in the central-northern of Malang-Tiaohu Sag .Effective traps are the main exploration targets in area with conventional reservoirs ,while the reservoirs and hydrocarbon source should be the focuses of study in area with tight reservoirs .%在三塘湖盆地马朗-条湖凹陷条湖组二段晶屑玻屑沉凝灰岩致密储层中发现了工业油流。为了研究致密油的分布规律,通过研究岩相和成岩作用对火山岩储层物性的影响,进行了成岩作用数值模拟,结合条湖组二段的岩相图,预测了4类储层在平面上的分布。结果表明,角砾岩和凝灰岩的物性最好,玻屑晶屑沉凝灰岩和火山碎屑沉积岩的物性次之,熔岩的物性最差;随成岩作用的增强,储层的物性变差,储层物性是岩性和成岩作用综合作用的结果。常规储层(孔隙度≥9%)分布在马朗-条湖凹陷的南部,低致密储层(7%≤孔隙度<9%)和高致密储层(4%≤孔隙度<7%)分布在凹陷的中北部。在

  15. Collecting Rocks

    Institute of Scientific and Technical Information of China (English)

    孙铮

    2007-01-01

    My hobby is collecting rocks.It is very special,isn’t it?I began to collect rocks about four years ago.I usually go hiking in the mountains,or near the river to look for rocks.When I find a rock,I pick it up and clean it with the brush and water.Then I put it into my bag.Most of the rocks I have collected are quartzite~*.They are really

  16. 基性岩油气储层白CO2封存潜力及可行性初探——以下辽河坳陷青龙台辉绿岩油气藏为例%POTENTIAL CAPACITY AND FEASIBILITY OF CO2 SEQUESTRATION IN PETROLEUM RESERVOIRS OF BASALTIC ROCKS: EXAMPLE FROM THE QINGLONGTAI DIABASE HYDROCARBON RESERVOIR IN THE EASTERN SAG OF XIALIAOHE DEPRESSION,BOHAI BAY BASIN,EAST CHINA

    Institute of Scientific and Technical Information of China (English)

    王震宇; 吴昌志; 季峻峰; 陈振岩; 陈旸; 李军; 杨光达; 顾连兴

    2011-01-01

    The Liaohe oilfield, situated in Xialiaohe Depression, Bohai Bay Basin, Eastern China, is famous for their igneous-related hydrocarbon reservoirs. The Qinglongtai diabase hydrocarbon reservoir, located in the central part of the eastern sag of the depression, covers an area of 1.3km2, with a proven oil geological reserve of 750, 000 tons and an output of 31.96 t of oil and current amount of 7856m3 of gas per day. In this paper,we analyze the geological features and reservoir characteristics of Qinglongtai diabase hydrocarbon reservoir. Combined with mineral and chemical compositions of four diabase core samples, we evaluate the feasibility of CO2 sequestration in petroleum reservoirs of basaltic rocks, and then estimate the CO2 storage capacity of minerals and oil and gas reservoir of the Qinglongtai diabase hydrocarbon reservoir. Our results show that reservoir spaces and minerals which suffer carbonation easily are favorable spots for CO2 sequestration, while the cap rocks can prevent the emission of CO2,and the stability of hydrocarbon reservoir can guarantee the safety of CO2 injection ,and should be an ideal target for CO2 sequestration. Estimates of theoretical capacity for CO2 storage assume that all the pore space freed up by the production of recoverable hydrocarbon reserves will be replaced by CO2. Therefore the theoretical storage capacity of oil and gas reservoirs can be estimated using most recent reserve databases from the Liaohe oilfield. Based on the principle of water-CO2-rock reaction, the capacity of the marie minerals in diabase for CO2 sequestration can also be calculated. According to the preliminary calculation, potential mineral capacity for reaction with CO2 is 46. 0 × 106 tons, while capacity of oil and gas reservoir to storage CO2 supercritical fluid is 4.90× 106 tons, and total capacity of CO2 sequestration for the Qinglongtai hydrocarbon reservoir is 18.4×l06 tons.%辉绿岩油气藏储层一方面含有大量可与CO2反应生成

  17. Monte Carlo reservoir analysis combining seismic reflection data and informed priors

    DEFF Research Database (Denmark)

    Zunino, Andrea; Mosegaard, Klaus; Lange, Katrine;

    2015-01-01

    Determination of a petroleum reservoir structure and rock bulk properties relies extensively on inference from reflection seismology. However, classic deterministic methods to invert seismic data for reservoir properties suffer from some limitations, among which are the difficulty of handling...

  18. basement reservoir geometry and properties

    Science.gov (United States)

    Walter, bastien; Geraud, yves; Diraison, marc

    2017-04-01

    Basement reservoirs are nowadays frequently investigated for deep-seated fluid resources (e.g. geothermal energy, groundwater, hydrocarbons). The term 'basement' generally refers to crystalline and metamorphic formations, where matrix porosity is negligible in fresh basement rocks. Geothermal production of such unconventional reservoirs is controlled by brittle structures and altered rock matrix, resulting of a combination of different tectonic, hydrothermal or weathering phenomena. This work aims to characterize the petro-structural and petrophysical properties of two basement surface analogue case studies in geological extensive setting (the Albert Lake rift in Uganda; the Ifni proximal margin of the South West Morocco Atlantic coast). Different datasets, using field structural study, geophysical acquisition and laboratory petrophysical measurements, were integrated to describe the multi-scale geometry of the porous network of such fractured and weathered basement formations. This study points out the multi-scale distribution of all the features constituting the reservoir, over ten orders of magnitude from the pluri-kilometric scale of the major tectonics structures to the infra-millimetric scale of the secondary micro-porosity of fractured and weathered basements units. Major fault zones, with relatively thick and impermeable fault core structures, control the 'compartmentalization' of the reservoir by dividing it into several structural blocks. The analysis of these fault zones highlights the necessity for the basement reservoirs to be characterized by a highly connected fault and fracture system, where structure intersections represent the main fluid drainage areas between and within the reservoir's structural blocks. The suitable fluid storage areas in these reservoirs correspond to the damage zone of all the fault structures developed during the tectonic evolution of the basement and the weathered units of the basement roof developed during pre

  19. Hot-dry-rock feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    1981-08-01

    The hot-dry-rock project tasks are covered as follows: hot-dry-rock reservoir; generation facilities; water resources; transmission requirements; environmental issues; government and community institutional factors; leasing, ownership and management of facilities; regulations, permits, and laws; and financial considerations. (MHR)

  20. Rock Stars

    Institute of Scientific and Technical Information of China (English)

    张国平

    2000-01-01

    Around the world young people are spending unbelievable sums of money to listen to rock music. Forbes Magazine reports that at least fifty rock stars have incomes between two million and six million dollars per year.

  1. KREEP Rocks

    Institute of Scientific and Technical Information of China (English)

    邹永廖; 徐琳; 欧阳自远

    2004-01-01

    KREEP rocks with high contents of K, REE and P were first recognized in Apollo-12 samples, and it was confirmed later that there were KREEP rock fragments in all of the Apollo samples, particularly in Apollo-12 and-14 samples. The KREEP rocks distributed on the lunar surface are the very important objects of study on the evolution of the moon, as well as to evaluate the utilization prospect of REE in KREEP rocks. Based on previous studies and lunar exploration data, the authors analyzed the chemical and mineral characteristics of KREEP rocks, the abundance of Th on the lunar surface materials, the correlation between Th and REE of KREEP rocks in abundance, studied the distribution regions of KREEP rocks on the lunar surface, and further evaluated the utilization prospect of REE in KREEP rocks.

  2. 基于三相孔隙弹性理论的火山岩气层岩石物理响应特征分析%Analysis of rock physics response of gas-bearing volcanic reservoir based on three-phase poroelastic theory

    Institute of Scientific and Technical Information of China (English)

    吴清岭; 赵海波; 李来林; 范兴才

    2008-01-01

    Unlike previous theories with velocity and/or elastic modulus averaging, we use a three-phase porous rock physics model developed by Santos for analyzing the seismic response of two immiscible fluids in saturated porous media. Considering reservoir reference pressure and coupling drag of two fluids in pores, the effects of frequency, porosity, and gas saturation on the phase velocities of the P- and S-waves are discussed in detail under field conditions. The effects of porosity and gas saturation on Vp/Vs are also provided. The data for our numerical experiments are from a sample of deep volcanic rock from Daqing. The numerical results show that the frequency dispersion effect can be ignored for deep volcanic rocks with low porosity and low permeability. It is concluded that for deep volcanic rocks the effect of gas content in pores on Vp/Vs is negligible but the effect of porosity is significant when there is a certain amount of water contained in the pores. The accurate estimate of lithology and porosity in this case is relatively more important.

  3. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  4. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  5. Rock Finding

    Science.gov (United States)

    Rommel-Esham, Katie; Constable, Susan D.

    2006-01-01

    In this article, the authors discuss a literature-based activity that helps students discover the importance of making detailed observations. In an inspiring children's classic book, "Everybody Needs a Rock" by Byrd Baylor (1974), the author invites readers to go "rock finding," laying out 10 rules for finding a "perfect" rock. In this way, the…

  6. Multilevel techniques for Reservoir Simulation

    DEFF Research Database (Denmark)

    Christensen, Max la Cour

    The subject of this thesis is the development, application and study of novel multilevel methods for the acceleration and improvement of reservoir simulation techniques. The motivation for addressing this topic is a need for more accurate predictions of porous media flow and the ability to carry...... Full Approximation Scheme) • Variational (Galerkin) upscaling • Linear solvers and preconditioners First, a nonlinear multigrid scheme in the form of the Full Approximation Scheme (FAS) is implemented and studied for a 3D three-phase compressible rock/fluids immiscible reservoir simulator...... based on element-based Algebraic Multigrid (AMGe). In particular, an advanced AMGe technique with guaranteed approximation properties is used to construct a coarse multilevel hierarchy of Raviart-Thomas and L2 spaces for the Galerkin coarsening of a mixed formulation of the reservoir simulation...

  7. Experimental research of gas injection displacement mechanism and efficiency in the fractured metamorphic rock reservoir%裂缝型变质岩油藏注气驱机理及驱替效率实验研究

    Institute of Scientific and Technical Information of China (English)

    林仁义; 孙雷; 梁宇; 黄堃

    2015-01-01

    采用物理模拟实验的方法,做注气膨胀实验,评价天然气在原油中的溶解性。通过数模和细管实验,确定目前地层压力和温度下的最小混相压力。开展双重介质变质岩油藏顶部注天然气,底部注水长岩心驱替实验(岩心夹持器呈30°倾斜),得出了裂缝和基质分别对采收率的贡献。驱替压力25.6 MPa和38.6 MPa,均小于最小混相压力,实验中天然气驱替过程为非混相驱。由于裂缝的收缩性远大于基质,衰竭采出的原油可以看作是裂缝的贡献。同时,由于基质与裂缝之间的渗透率相差极大,因此在初期的驱替过程中,裂缝中的原油可以被完全驱出。结合以上分析,可以由最终实验结果得出基质与裂缝系统各自对采收率的贡献。%The swelling test is conducted under physical simulation to analyze the natural gas solvency in the crude oil. MMP is cal⁃culated by simulation and slim tube experiment under the current pressure and temperature situation. The long core displacement experiment on the double medium metamorphic reservoir rock cores is conducted to get the recovery of the contribution from the matrix and fractures respectively, including natural gas injection on the top and water injection at the bottom of the long core(the core holder is 30° to the horizontal direction). The displacement pressure is 25.6 MPa and 38.6 MPa, lower than the MMP, meaning that the whole procedure is immiscible displacement. Contractility of fractures is much larger than matrix, thus the oil recovery from the depletion can be treated as the contribution of fractures. And the assumption can be made that the oil are completely out of the fractures in the initial displacement process because of the great permeability difference between fractures and matrix. Based on the analysis above, the contribution to the final recovery of the fractures and matrix respectively can be obtained from the experi

  8. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  9. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  10. Modeling of Salinity Effects on Waterflooding of Petroleum Reservoirs

    DEFF Research Database (Denmark)

    Alexeev, Artem

    of the experimental studies concerning the smart water effects recognize importance of the chemistry of reservoir rocks that manifests itself in dissolution and precipitation of rock minerals and adsorption of specific ions on the rock surface. The brine-rock interactions may affect the wetting state of the rock...... brine and the formation water that is initially in equilibrium with the reservoir rock. We consider a displacement process in one dimension with dissolution affecting both the porosity/permeability of the rock and the density of the brine. Extending previous studies, we account for the different...... of residual oil and its flow in porous media. The oil trapped in the swept zones after conventional flooding is present in a form of disconnected oil drops, or oil ganglia. While the macroscopic theory of multiphase flow assumes that fluid phases flow in their own pore networks and do not influence each other...

  11. 'Earhart' Rock

    Science.gov (United States)

    2004-01-01

    This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock informally named 'Earhart' on the lower slopes of 'Endurance Crater.' The rock was named after the pilot Amelia Earhart. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe fractures in Earhart could have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Rover team members do not have plans to investigate Earhart in detail because it is located across potentially hazardous sandy terrain. This image was taken on sol 219 (Sept. 4) by the rover's panoramic camera, using its 750-, 530- and 430-nanometer filters.

  12. Rock Art

    OpenAIRE

    Huyge, Dirk

    2009-01-01

    Rock art, basically being non-utilitarian, non-textual anthropic markings on natural rock surfaces, was an extremely widespread graphical practice in ancient Egypt. While the apogee of the tradition was definitely the Predynastic Period (mainly fourth millennium BCE), examples date from the late Palaeolithic (c. 15,000 BCE) until the Islamic era. Geographically speaking, “Egyptian” rock art is known from many hundreds of sites along the margins of the Upper Egyptian and Nubian Nile Valley and...

  13. Rock blocks

    OpenAIRE

    Turner, W.

    2007-01-01

    Consider representation theory associated to symmetric groups, or to Hecke algebras in type A, or to q-Schur algebras, or to finite general linear groups in non-describing characteristic. Rock blocks are certain combinatorially defined blocks appearing in such a representation theory, first observed by R. Rouquier. Rock blocks are much more symmetric than general blocks, and every block is derived equivalent to a Rock block. Motivated by a theorem of J. Chuang and R. Kessar in the case of sym...

  14. Investigation of oil-pool formation from the homogenization temperatures of fluid inclusions and biomarkers in reservoir rocks: a genetic model for the Deng-2 oil-pool in the Jiyuan Depression

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Weiwei [Geochemical Institute of Chinese Academy, Guizhou (China); University of Petroleum, Shandong (China); Li Zhaoyang [University of Petroleum, Shandong (China); Jin Qiang; Wang Weifeng [Geochemical Institute of Chinese Academy, Guizhou (China)

    2002-11-01

    The Jiyuan Depression is a frontier area for oil and gas exploration in Henan Province, China. In recent years, oil was discovered in the Deng-2 well in the lower Tertiary, though the tectonics and petroleum geology of the Depression are very complex. A series of experiments on fluid inclusions in the oil-bearing sandstones from the Deng-2 well were made that included measurement of the homogenization temperatures of gas-liquid inclusions and GC-MS analysis of biomarkers either in the sandstone pores or in the fluid inclusions. The Deng-2 oil-reservoir was formed at about 78{sup o}C, corresponding to a burial depth of about 2200 m. The present burial depth is about 700 m because of erosion and fault-block uplift in Oligocene time. Although oil in the sandstone pores is now heavily biodegraded, the biomarkers in the inclusions show slight biodegradation representing a watering and biodegradation process that did not occur before formation of the Deng-2 oil- pool. Having investigated the structural evolution of the Deng-2 trap, it is concluded that the oil discovered in the Tertiary reservoir of Deng-2 well migrated from Mesozoic reservoirs through active faults around the Deng-2 trap. As the oil migrated from the Mesozoic to the Tertiary reservoir, the Deng-2 trap was uplifted close to the depth of active biodegradation (subsurface temperature lower than 80{sup o}C and to a burial depth shallower than 2250 m from the thermal gradient of 3.1{sup o}C/100 m) so that the oil in the inclusions shows a slight biodegradation. Because of the continuous uplift of the Deng-2 trap during the Tertiary and Quaternary, the reservoired oil has been more heavily biodegraded compared to that in the inclusions. (author)

  15. Production-induced changes in reservoir geomechanics

    Science.gov (United States)

    Amoyedo, Sunday O.

    Sand production remains a source of concern in both conventional and heavy oil production. Porosity increase and changes in local stress magnitude, which often enhance permeability, have been associated with severe sanding. On the other hand, sand production has been linked to a large number of field incidences involving loss of well integrity, casing collapse and corrosion of down-hole systems. It also poses problems for separators and transport facilities. Numerous factors such as reservoir consolidation, well deviation angle through the reservoir, perforation size, grain size, capillary forces associated with water cut, flow rate and most importantly reservoir strain resulting from pore pressure depletion contribute to reservoir sanding. Understanding field-specific sand production patterns in mature fields and poorly consolidated reservoirs is vital in identifying sand-prone wells and guiding remedial activities. Reservoir strain analysis of Forties Field, located in the UK sector of the North Sea, shows that the magnitude of the production-induced strain, part of which is propagated to the base of the reservoir, is of the order of 0.2 %, which is significant enough to impact the geomechanical properties of the reservoir. Sand production analysis in the field shows that in addition to poor reservoir consolidation, a combined effect of repeated perforation, high well deviation, reservoir strain and high fluid flow rate have contributed significantly to reservoir sanding. Knowledge of reservoir saturation variation is vital for in-fill well drilling, while information on reservoir stress variation provides a useful guide for sand production management, casing design, injector placement and production management. Interpreting time-lapse difference is enhanced by decomposing time-lapse difference into saturation, pressure effects and changes in rock properties (e.g. porosity) especially in highly compacting reservoirs. Analyzing the stress and saturation

  16. 海拉尔盆地乌南地区下白垩统火山碎屑岩孔隙结构特征与储层分类%Pore Structure of Volcaniclastic Rock and Reservoir Classification in Lower Cretaceous of South Wuerxun Area in Hailar Basin

    Institute of Scientific and Technical Information of China (English)

    王宏建

    2012-01-01

    海拉尔盆地乌南地区下白垩统储层的岩性主要为火山熔岩、火山碎屑岩和正常沉积岩.以往的储层研究均遵循根据岩性建立测井解释方法的思路.根据乌南地区储层同种岩性具有不同测井响应、不同岩性又具有相同测井的特征,采用压汞实验分析与岩心孔渗试油分析相结合,建立本区的实验室条件下的储层分类标准,并利用常规测井资料建立乌南地区测井储层分类标准.压汞实验资料与岩心孔渗试油资料显示研究区储层可以分为三大类]四小类):I类储层的孔隙以溶蚀粒间孔为主,黏土矿物以分散式和内衬式充填;ⅡA类储层孔隙主要是熔蚀粒间孔和溶蚀粒内孔,黏土矿物以搭桥式或以内衬式充填;ⅡB类储层主要为溶蚀粒内孔,黏土矿物以搭桥式充填;Ⅲ类储层在铸体薄片中几乎观察不到有效的孔隙,黏土矿物堵塞孔喉.采用XD-N与DEN或CNL做交会图,能有效区分乌南地区储层类别,储层分类判别符合率达到88.9%.%The objective interval of reservoir rocks in lower Cretaceous of Wunan area, Hailer basin mainly are volcanic lava, pyroclastic and sedimentary. Previous studies had been done in a method usually seting up logging interpretation by using lithology. In this paper it is analyzed that one kind of lithology may be different logging responses while some kinds of lithology may have one logging charateristics in Wunan area. A reservior classification standard under laboratory condition is build up by the methods of studying on mercury porosimetry test information link with porosity, permeability and testing oil data of core analysis. A logging evaluation reservior classification standard of Wunan area is build up using conventional logging data in this aera. Three kinds of reservoirs are be classified. Description of rock core and microscopic sections show that the main type pore of reservoir I is corrosion intergranular pore. The

  17. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-12-31

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  18. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-01-01

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  19. FRACTURED PETROLEUM RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Abbas Firoozabadi

    1999-06-11

    The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly

  20. Facies-controlled volcanic reservoirs of northern Songliao Basin, NE China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Volcanic rocks of the late Mesozoic are very important reservoirs for the commercial natural gases including hydrocarbon, carbon dioxide and rare gases in the northern Songliao Basin. The reservoir volcanic rocks include rhyolite,andesite, trachyte, basalt and tuff. Facies of the volcanic rocks can be classified into 5 categories and 15 special types.Porosity and permeability of the volcanic reservoirs are facies-controlled. Commercial reservoirs were commonly found among the following volcanic subfacies: volcanic neck (Ⅰ1), underground-explosive breccia (Ⅰ3), pyroclastic-bearing lava flow (Ⅱ3), upper effusive (Ⅲ3) and inner extrusive ones (Ⅳ1). The best volcanic reservoirs are generally evolved in the interbedded explosive and effusive volcanics. Rhyolites show in general better reservoir features than other types of rocks do.

  1. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  2. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  3. 全谱饱和度测井在塔河碎屑岩储层评价中的应用%The Applications of Pulsed Neutron Spectrum Saturation Log to Clastic Rock Reservoir Evaluation in Tahe Oilfield

    Institute of Scientific and Technical Information of China (English)

    王勤聪; 马立新; 许克亮; 邹宁

    2013-01-01

    介绍全谱饱和度测井仪(PSSL)技术原理,对比不同脉冲中子测井仪器的优缺点,评价PSSL饱和度测井仪碳氧比组合中子寿命测井模式在塔河油田低孔隙度低渗透率储层中应用效果及PSSL俘获模式在凝析气藏储层中应用,通过PND俘获模式与PSSL俘获模式测井资料对比,评价仪器性能,分析时间推移测井应用.全谱饱和度测井能定量评价储层并可将储层进行精细划分;对于同一套地层,利用纵横向渗透率级差可以进行层内剩余油解释和评价.与传统脉冲中子测井对比,PSSL仪器使用范围宽,测井成本低,录取资料信息多,能有效反映储层剩余油饱和度的变化情况,为寻找潜力油层、识别水淹层提供了科学依据.%We discuss the technology principle of the PSSL(Pulsed Neutron Spectrum Saturation Log) logging tool.With comparing the advantages and disadvantages of different pulse neutron logging tool,we evaluate the application effect of Carbon-Oxygen Ratio combined capture modes of PSSL logging in low porosity reservoirs and capture mode of PSSL in condensate gas reservoir in Tahe oilfield.Through the logging data contrast and analysis of PND capture mode and PSSL capture mode,we evaluate the tool performance and analyze time lapse logging application.PSSL logging mode can quantitatively evaluate reservoirs and finely divide reservoirs; can interpret and evaluate residual oil by longitudinal and vertical permeability range in the same layer.Compared with traditional pulsed neutron logging,PSSL tool has wider applications,provides rich information and lower logging cost; it can reflect changes in the remaining oil saturation in reservoirs.It provides the basis for finding potential oil layers and identification of water out layers.

  4. Fractures and Rock Mechanics, Phase 1

    DEFF Research Database (Denmark)

    Havmøller, Ole; Krogsbøll, Anette

    1997-01-01

    The main objectives of the project are to combine geological description of fractures, chalk types and rock mechanical properties, and to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. Five chalk types, representing two outcrop localities: Stevns and Hillers......The main objectives of the project are to combine geological description of fractures, chalk types and rock mechanical properties, and to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. Five chalk types, representing two outcrop localities: Stevns...

  5. High-resolution rock structure image processing method and its applications in carbonate reservoir evaluation%高清晰岩石结构图像处理方法及其在碳酸盐岩储层评价中的应用

    Institute of Scientific and Technical Information of China (English)

    柴华; 李宁; 夏守姬; 武宏亮; 郭宏伟; 王克文; 冯周; 梁明星

    2012-01-01

    电阻率成像测井已经成为解决非均质复杂碎屑岩储层、缝洞型碳酸盐岩储层、火山岩储层问题不可或缺的关键手段之一,而且正在逐渐从高端测井技术走进常规系列.目前主流的成像处理方法中,普遍采用了基于像素分布特征统计的图像增强方法.该方法相对于最初的线性图像增强方法,效果明显改善,然而在处理中未能考虑岩石结构特征的分布规律,经常导致重要的地质特征被湮没在次要特征和噪声中.笔者在传统图像增强方法的基础上,进一步以结构信息为核心要素,提出了基于岩石结构的图像增强方法.该方法以岩石结构特征判别为基础,有针对性地提高图像中关键信息的权重,弱化背景和噪声,并针对结构特征分布规律进行成像色标动态优化,从而显著提高了图像的有效信息量和清晰度,为进一步的精细解释工作提供了先决条件.%The resistivity imaging logging is known as one of the indispensable means for solving problems of heterogeneous complex clastic reservoirs fractured-vuggy carbonate reservoirs, and volcanic reservoirs. The previous high-end logging technology is gradually considered to be a routine method. At present, the mainstream image processing approaches commonly employ the image enhancement methods based on the pixel distribution characteristics. Despite substantial improvement compared to the original linear image enhancement method, the distribution-based image enhancement methods do not take into account the distributions of rock structural features, commonly leading to the submergence of major geological features in minor features and noises. On the basis of conventional image enhancement methods, this study focused on rock structure information and proposed a new rock structure-based image enhancement method. Based on the identification of rock structural features, the proposed method was shown to increase the weight of targeted

  6. ROCK ON

    National Research Council Canada - National Science Library

    Thomas Grose

    2014-01-01

    ..., however, was music - especially the high-pitched sounds of pop and rock, which boosted energy output by up to 40 percent. By contrast, classical music's lower pitches barely raised effectiveness. O...

  7. Control of Formation of Lithological Reservoirs by Surrounding Mudstone

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Taking the Jiyang depression as an example, this paper discusses the control of the formation of lithological reservoir by surrounding rocks by integrated application of geological analysis, physical simulation, and the analysis of oil & gas accumulation mechanism. Geological statistical shows that the major burial depth and interval of lithological reservoirs in the Jiyang depression are related to the hydrocarbon generation in and expulsion from the Lower Tertiary source rocks and the time of the formation of most lithological reservoirs coincides with the peak of hydrocarbon generation and expulsion. The lithological traps located in the center of effective source rocks are propitious to high oil saturation than those located on the margin of effective source rocks. The hydrocarbon charge degree of the lithological reservoir has a positive correlation with the intensity of hydrocarbon expulsion from surrounding source rocks.Geological analyses and NMR experiments also show that the oil saturation of surrounding source rocks control the hydrocarbon potential of lithological traps, and a critical value for oil saturation of surrounding mudstone is required, that is, when the oil saturation of surrounding mudstone is lower than this critical value, no oil and gas accumulate in the lithological trap. The control of surrounding mudstone on the oil-bearing properties of lithological reservoirs is also analyzed by the mechanisms of hydrocarbon generation and expulsion as well as accumulation.

  8. 南海莺歌海盆地储层岩石特殊物性参数特征分析%Analysis of Characteristics of Special Physical Parameters of Yinggehai Basin Reservoir Rock in South China Sea

    Institute of Scientific and Technical Information of China (English)

    张凤伟

    2016-01-01

    Yinggehai basin is in the west of Yinggehai waters in Hainan Island. It is the m ain basin of Hainan Island. Its exploration potential is huge but product difficulty is also a huge challenge.Based on the YinggehaiBasin Reservoir conventional statistical properties and form ation conditions of the physical param eters of the statistical, we analysis the conventional physical param eters of reservoir form ation conditions and physical param eters influencing factors.And we also find out different pressure and temperature conditions of porosity and perm eability variation, different form ations for different regions of the reservoir properties and comparative statistics.%莺歌海盆地位于海南岛西侧的莺歌海海域,是南海的主要盆地,其勘探潜力巨大,其生产难度也极具挑战性。本文通过对莺歌海盆地储层常规物性统计和地层条件下物性的统计,分析储层常规物性参数和地层条件下物性参数的影响因素,研究不同压力温度条件下孔隙度和渗透率的变化规律,分析岩石的纵横波速度的影响因素,以及岩石的纵横波速度在不同温度和压力条件下的变化规律。

  9. Issues in geothermal reservoir engineering, modeling, and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pritchett, J.W. (S-Cubed, La Jolla, CA (United States))

    1996-01-01

    The theoretical basis of geothermal reservoir engineering owes much of its origins to the oil and gas industries, but important differences in resource character and geological setting have resulted in substantial divergences from reservoir simulation as practiced in the petroleum industry. Geothermal reservoirs are hotter, contain different fluids, and are usually found within fractured volcanic formations with little or no intergranular permeability. Fluid flow takes place through an intricate fracture network which penetrates the otherwise impermeable rock. By their very nature, oil and gas fields prior to production are usually static (little or no natural fluid circulation) whereas, by contrast, the presence of a dynamic active natural convective circulation system is an essential prerequisite to the formation of a geo-thermal reservoir-otherwise, the earth's heat cannot penetrate upward to drillable depths. Geothermal reservoirs usually lack the regular sub-horizontal stratification pattern typical of oilfields. The resource sought (heat) is mainly contained within the mass of the rock, so that the geothermal brines serve as working fluids to redistribute this heat within the reservoir and carry it upward. During exploitation, flow rates are necessarily high (the economic value per unit mass of hot brine is vastly less than that of oil), and the objective is to create an artificial circulation system using production and injection wells to mine energy from the reservoir by cooling the rock. These phenomenological differences have resulted in development of new techniques of reservoir modeling and simulation for geothermal applications.

  10. Issues in geothermal reservoir engineering, modeling, and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pritchett, J.W. [S-Cubed, La Jolla, CA (United States)

    1996-12-31

    The theoretical basis of geothermal reservoir engineering owes much of its origins to the oil and gas industries, but important differences in resource character and geological setting have resulted in substantial divergences from reservoir simulation as practiced in the petroleum industry. Geothermal reservoirs are hotter, contain different fluids, and are usually found within fractured volcanic formations with little or no intergranular permeability. Fluid flow takes place through an intricate fracture network which penetrates the otherwise impermeable rock. By their very nature, oil and gas fields prior to production are usually static (little or no natural fluid circulation) whereas, by contrast, the presence of a dynamic active natural convective circulation system is an essential prerequisite to the formation of a geo-thermal reservoir-otherwise, the earth`s heat cannot penetrate upward to drillable depths. Geothermal reservoirs usually lack the regular sub-horizontal stratification pattern typical of oilfields. The resource sought (heat) is mainly contained within the mass of the rock, so that the geothermal brines serve as working fluids to redistribute this heat within the reservoir and carry it upward. During exploitation, flow rates are necessarily high (the economic value per unit mass of hot brine is vastly less than that of oil), and the objective is to create an artificial circulation system using production and injection wells to mine energy from the reservoir by cooling the rock. These phenomenological differences have resulted in development of new techniques of reservoir modeling and simulation for geothermal applications.

  11. Ordovician Basement Hydrocarbon Reservoirs in the Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    YAN Xiangbin; LI Tiejun; ZHANG Tao

    2004-01-01

    Ordovician marine carbonate basement traps are widely developed in the paleo-highs and paleo-slopes in the Tarim Basin. Reservoirs are mainly altered pore-cavity-fissure reservoirs. Oil sources are marine carbonate rocks of the Lower Paleozoic. Thus, the paleo-highs and paleo-slopes have good reservoiring conditions and they are the main areas to explore giant and large-scale oil reservoirs. The main factors for their reservoiring are: (1) Effective combination of fenestral pore-cavity-fracture reservoirs, resulting from multi-stage, multi-cyclic karstification (paleo-hypergene and deep buried) and fracturing, with effective overlying seals, especially mudstone and gypsum mudstone in the Carboniferous Bachu Formation, is essential to hydrocarbon reservoiring and high and stable production; (2) Long-term inherited large rises and multi-stage fracture systems confine the development range of karst reservoirs and control hydrocarbon migration, accumulation and reservoiring; (3) Long-term multi-source hydrocarbon supply, early reservoiring alteration and late charging adjustment are important reservoiring mechanisms and determine the resource structure and oil and gas properties. Favorable areas for exploration of Ordovician carbonate basement hydrocarbon reservoirs in the Tarim Basin are the Akekule rise, Katahe uplift, Hetianhe paleo-high and Yakela faulted rise.

  12. Application of Rock Hydraulic Flow Unit Method to Productivity Prediction of Ultra-low Permeability Reservoir%岩石水力流动单元法在超低渗透率油层产能预测中的应用

    Institute of Scientific and Technical Information of China (English)

    赵杰; 高坤; 文玉莲; 李伸专; 朱友清

    2012-01-01

    引入岩石水力流动单元概念,以测井综合评价为基础,利用神经网络技术建立测井响应与岩石水力流动单元关系,根据岩心数据和测井响应划分储层垂向流动单元,并针对每一类型的流动单元确定其孔隙度、渗透率相关性.提出了确定流体性质等参数和泄油半径、水力压裂裂缝等参数以及裂缝渗透率、表皮系数的原则.基于流动单元划分和改进的孔渗关系描述,应用拟稳态流产能预测方法进行在不同完井方式下的产能预测,该方法在大庆油田长垣扶杨油藏25口井压裂前后的产能预测中取得了良好的应用效果.%This paper introduces the concept of rock hydraulic flow unit. Based on integrated log evaluation, we build the relationship between logging responses and rock hydraulic flow unit using neural network technology, and then, divide vertical reservoir flow unit according to logging responses and determine the unique correlation between porosity and permeability for each type of flow unit. Proposes the rules of parameter determination, such as, parameters to determine flow property, oil leakage radius, hydraulic fracture, fracture permeability and epidermis coefficient. Based on the flow unit division and improvement of porosity and permeability relationship description, uses pseudo steady-state method in different completion modes to predict the reservoir production. This method achieves good results in the productivity prediction comparison before and after fracturing for 25 wells of Changyuan Fuyang reservoir in Daqing oilfield.

  13. Reservoir engineering. 1995 SPE annual technical conference and exhibition

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document contains the proceedings of the Annual Technical Conference and Exhibition of the Society of Petroleum Engineers which was held on October 22-25, 1995 in Dallas, Texas. This volume contains the presentations regarding Reservoir Engineering. The topics covered in these presentations include: resource management and reservoir engineering of oil, natural gas and gas condensate fields, mathematical models and computerized simulation of fluid flow in reservoir rock, geochemistry of reservoir fluids, and enhanced recovery of oil and natural gas using waterflooding and other secondary recovery methods.

  14. Diagenesis of clastic rock of Palaeozoic and its influence on reservoir in Tazhong area, Tarim basin%塔中地区古生界碎屑岩成岩作用及其对储层的影响

    Institute of Scientific and Technical Information of China (English)

    徐燕军; 于炳松; 钟大康

    2013-01-01

      通过取心井常规薄片、铸体薄片、扫描电镜、X 衍射等资料的分析,研究了塔里木盆地塔中地区古生界碎屑岩成岩作用及其对储层发育的影响。研究结果显示,研究区碎屑岩储层处于中成岩 A 期,且经历的主要成岩作用有压实与压溶作用、胶结作用、溶蚀作用、交代作用和重结晶作用等。另外,这些成岩作用对储集层孔隙发育及储层性质具有明显的影响:压实与压溶作用、交代、胶结作用、石英长石的次生加大以及重结晶作用使储层孔隙体积减小、物性变差,如压实与压溶作用使本区储层孔隙度损失14.1%~25.3%,交代、胶结作用使孔隙度损失13.9%;溶蚀作用是增加储集空间、改善储层物性最重要的成岩作用,如石英、长石及岩屑颗粒的溶蚀作用使储层产生次生孔隙,导致本区储层孔隙度平均增加6%~8%。%  Based on the full analysis of the data such as conventional section, cast section, X-ray diffraction and SEM, the Paleaozoic clastic diagenesis and its influence on clastic reservoir development in Tazhong area have been studied. The results of the study indicate that the clastic reservoir is in the stage A of middle diagenesis and the major diagenesis includes compaction, cementation(siliceous cementation, carbonate cementation and hydro-syalite cementation), dissolution(feldspar, minor debris and carbonate cement), alternation and fracture along with the sedimentary and diagenesis history. These diagenism has markedly influenced the pore development and physical properties of the reservoir. The mechanical compaction, the subsequent volcanism of quartz and feldspar has destructive influence on the physical properties of the reservoir. Compaction and pressure solution have in-duced the decrease in porosity(14.1%~25.3% ), the cement has filled up and blocked the pore throat of sandstone in various ways; Secondary overgrowth of quartz could

  15. Reservoir-on-a-Chip (ROC): A new paradigm in reservoir engineering

    NARCIS (Netherlands)

    Kumar Gunda, N.S.; Bera, B.; Karadimitriou, N.K.; Mitra, S.K.; Hassanizadeh, S.M.

    2011-01-01

    In this study, we design a microfluidic chip, which represents the pore structure of a naturally occurring oil-bearing reservoir rock. The pore-network has been etched in a silicon substrate and bonded with a glass covering layer to make a complete microfluidic chip, which is termed as

  16. 'Wopmay' Rock

    Science.gov (United States)

    2004-01-01

    This approximate true-color image taken by NASA's Mars Exploration Rover Opportunity shows an unusual, lumpy rock informally named 'Wopmay' on the lower slopes of 'Endurance Crater.' The rock was named after the Canadian bush pilot Wilfrid Reid 'Wop' May. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe the lumps in Wopmay may be related to cracking and alteration processes, possibly caused by exposure to water. The area between intersecting sets of cracks eroded in a way that created the lumpy appearance. Rover team members plan to drive Opportunity over to Wopmay for a closer look in coming sols. This image was taken by the rover's panoramic camera on sol 248 (Oct. 4, 2004), using its 750-, 530- and 480-nanometer filters.

  17. Seismic Imaging of Reservoir Structure at The Geysers Geothermal Reservoir

    Science.gov (United States)

    Gritto, R.; Yoo, S.; Jarpe, S.

    2013-12-01

    Three-dimensional Vp/Vs-ratio structure is presented for The Geysers geothermal field using seismic travel-time data. The data were recorded by the Lawrence Berkeley National Laboratory (LBNL) using a 34-station seismic network. The results are based on 32,000 events recorded in 2011 and represent the highest resolution seismic imaging campaign at The Geysers to date. The results indicate low Vp/Vs-ratios in the central section of The Geysers within and below the current reservoir. The extent of the Vp/Vs anomaly deceases with increasing depth. Spatial correlation with micro-seismicity, used as a proxy for subsurface water flow, indicates the following. Swarms of seismicity correlate well with areas of high and intermediate Vp/Vs estimates, while regions of low Vp/Vs estimates appear almost aseismic. This result supports past observations that high and low Vp/Vs-ratios are related to water and gas saturated zones, respectively. In addition, the correlation of seismicity to intermediate Vp/Vs-ratios is supportive of the fact that the process of water flashing to steam requires four times more energy than the initial heating of the injected water to the flashing point. Because this energy is dawn from the reservoir rock, the associated cooling of the rock generates more contraction and thus seismic events than water being heated towards the flashing point. The consequences are the presence of some events in regions saturated with water, most events in regions of water flashing to steam (low steam saturation) and the absence of seismicity in regions of high steam concentrations where the water has already been converted to steam. Furthermore, it is observed that Vp/Vs is inversely correlated to Vs but uncorrelated to Vp, leading support to laboratory measurements on rock samples from The Geysers that observe an increase in shear modulus while the core samples are dried out. As a consequence, traditional poroelastic theory is no applicable at The Geysers geothermal

  18. Source rock

    OpenAIRE

    Abubakr F. Makky; Mohamed I. El Sayed; Ahmed S. Abu El-Ata; Ibrahim M. Abd El-Gaied; Mohamed I. Abdel-Fattah; Zakaria M. Abd-Allah

    2014-01-01

    West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history ...

  19. The validity of generic trends on multiple scales in rock-physical and rock-mechanical properties of the Whitby Mudstone, United Kingdom

    NARCIS (Netherlands)

    Douma, L.A.N.R.; Primarini, M.I.W.; Houben, M.E.; Barnhoorn, A.

    2017-01-01

    Finding generic trends in mechanical and physical rock properties will help to make predictions of the rock-mechanical behaviour of shales. Understanding the rock-mechanical behaviour of shales is important for the successful development of unconventional hydrocarbon reservoirs. This paper presents

  20. The validity of generic trends on multiple scales in rock-physical and rock-mechanical properties of the Whitby Mudstone, United Kingdom

    NARCIS (Netherlands)

    Douma, L.A.N.R.; Primarini, M.I.W.; Houben, M.E.; Barnhoorn, A.

    Finding generic trends in mechanical and physical rock properties will help to make predictions of the rock-mechanical behaviour of shales. Understanding the rock-mechanical behaviour of shales is important for the successful development of unconventional hydrocarbon reservoirs. This paper presents

  1. Fractures and Rock Mechanics, Phase 1

    DEFF Research Database (Denmark)

    Krogsbøll, Anette; Jakobsen, Finn; Madsen, Lena

    1997-01-01

    The main objective of the project is to combine geological descriptions of fractures, chalk types and rock mechanical properties in order to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. This report deals with 1) geological descriptions of outcrop locality...

  2. Standing Rock Rural Water System NPDES Permit

    Science.gov (United States)

    Under NPDES permit SD-0030996, the Standing Rock Rural Water System is authorized to discharge from its wastewater treatment facility in Corson County, South Dakota, to an unnamed tributary to Fisher Creek, a tributary to Oahe Reservoir on the Missouri R.

  3. Fractures and Rock Mechanics, Phase 1

    DEFF Research Database (Denmark)

    Krogsbøll, Anette; Jakobsen, Finn; Madsen, Lena

    1997-01-01

    The main objective of the project is to combine geological descriptions of fractures, chalk types and rock mechanical properties in order to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. This report deals with 1) geological descriptions of outcrop locality...

  4. Rock Paintings.

    Science.gov (United States)

    Jones, Julienne Edwards

    1998-01-01

    Discusses the integration of art and academics in a fifth-grade instructional unit on Native American culture. Describes how students studied Native American pictographs, designed their own pictographs, made their own tools, and created rock paintings of their pictographs using these tools. Provides a list of references on Native American…

  5. Ayers Rock

    Institute of Scientific and Technical Information of China (English)

    王慧茹

    2002-01-01

    Ayers Rock is right in the centre of Australia.It's nearly two thousand kilometres______Sydney.So we flew most of the way.h was rather cloudy______But after we left the mountains behind us, there was hardly a cloud in thesky.

  6. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  7. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  8. Current Challenges in Geothermal Reservoir Simulation

    Science.gov (United States)

    Driesner, T.

    2016-12-01

    Geothermal reservoir simulation has long been introduced as a valuable tool for geothermal reservoir management and research. Yet, the current generation of simulation tools faces a number of severe challenges, in particular in the application for novel types of geothermal resources such as supercritical reservoirs or hydraulic stimulation. This contribution reviews a number of key problems: Representing the magmatic heat source of high enthalpy resources in simulations. Current practice is representing the deeper parts of a high enthalpy reservoir by a heat flux or temperature boundary condition. While this is sufficient for many reservoir management purposes it precludes exploring the chances of very high enthalpy resources in the deepest parts of such systems as well as the development of reliable conceptual models. Recent 2D simulations with the CSMP++ simulation platform demonstrate the potential of explicitly including the heat source, namely for understanding supercritical resources. Geometrically realistic incorporation of discrete fracture networks in simulation. A growing number of simulation tools can, in principle, handle flow and heat transport in discrete fracture networks. However, solving the governing equations and representing the physical properties are often biased by introducing strongly simplifying assumptions. Including proper fracture mechanics in complex fracture network simulations remains an open challenge. Improvements of the simulating chemical fluid-rock interaction in geothermal reservoirs. Major improvements have been made towards more stable and faster numerical solvers for multicomponent chemical fluid rock interaction. However, the underlying thermodynamic models and databases are unable to correctly address a number of important regions in temperature-pressure-composition parameter space. Namely, there is currently no thermodynamic formalism to describe relevant chemical reactions in supercritical reservoirs. Overcoming this

  9. Reservoir geochemistry. A reservoir engineering perspective

    Energy Technology Data Exchange (ETDEWEB)

    England, W.A. [BP Exploration, Chertsey Road, Sunbury-on-Thames, Middlesex, TW16 7LN (United Kingdom)

    2007-09-15

    This paper reviews the applications of reservoir geochemistry from a reservoir engineering point of view. Some of the main tasks of reservoir engineering are discussed with an emphasis on the importance of appraising reservoirs in the pre-development stage. A brief review of the principal methods and applications of reservoir geochemistry are given, in the context of applications to reservoir engineering problems. The importance of compositional differences in fluid samples from different depths or spatial locations is discussed in connection with the identification of internal flow barriers. The importance of understanding the magnitude and origin of vertical compositional gradients is emphasised because of possible confusion with purely lateral changes. The geochemical origin and rate of dissipation of compositional differences over geological time is discussed. Geochemical techniques suitable for bulk petroleum fluid samples include GC fingerprinting, GCMS, isotopic and PVT measurements. Core sample petroleum extracts may also be studied by standard geochemical methods but with the added complication of possible contamination by drilling mud. Aqueous phase residual salt extracts can be studied by strontium isotope analysis from core samples. Petroleum fluid inclusions allow the possibility of establishing the composition of paleo-accumulations. The problems in predicting flow barriers from geochemical measurements are discussed in terms of 'false positives' and 'false negatives'. Suggestions are made for areas that need further development in order to encourage the wider acceptance and application of reservoir geochemistry by the reservoir engineering community. The importance of integrating all available data is emphasised. Reservoir geochemistry may be applied to a range of practical engineering problems including production allocation, reservoir compartmentalisation, and the prediction of gravitational gradients. In this review

  10. Reservoir assessment of The Geysers Geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R.P.; Chapman, R.H.; Dykstra, H.

    1981-01-01

    Big Sulphur Creek fault zone, in The Geysers Geothermal field, may be part of a deep-seated, wrench-style fault system. Hydrothermal fluid in the field reservoir may rise through conduits beneath the five main anomalies associated with the Big Sulphur Creek wrench trend. Some geophysical anomalies (electrical resistivity and audio-magnetotelluric) evidently are caused by the hot water geothermal field or zones of altered rocks; others (gravity, P-wave delays, and possibly electrical resistivity) probably respresent the underlying heat source, a possible magma chamber; and others (microearthquake activity) may be related to the steam reservoir. A large negative gravity anomaly and a few low-resistivity anomalies suggest areas generally favorable for the presence of steam zones, but these anomalies apparently do not directly indicate the known steam reservoir. At the current generating capacity of 930 MWe, the estimated life of The Geysers Geothermal field reservoir is 129 years. The estimated reservoir life is 60 years for the anticipated maximum generating capacity of 2000 MWe as of 1990. Wells at The Geysers are drilled with conventional drilling fluid (mud) until the top of the steam reservoir is reached; then, they are drilled with air. Usually, mud, temperature, caliper, dual induction, and cement bond logs are run on the wells.

  11. Large reservoirs: Chapter 17

    Science.gov (United States)

    Miranda, Leandro E.; Bettoli, Phillip William

    2010-01-01

    Large impoundments, defined as those with surface area of 200 ha or greater, are relatively new aquatic ecosystems in the global landscape. They represent important economic and environmental resources that provide benefits such as flood control, hydropower generation, navigation, water supply, commercial and recreational fisheries, and various other recreational and esthetic values. Construction of large impoundments was initially driven by economic needs, and ecological consequences received little consideration. However, in recent decades environmental issues have come to the forefront. In the closing decades of the 20th century societal values began to shift, especially in the developed world. Society is no longer willing to accept environmental damage as an inevitable consequence of human development, and it is now recognized that continued environmental degradation is unsustainable. Consequently, construction of large reservoirs has virtually stopped in North America. Nevertheless, in other parts of the world construction of large reservoirs continues. The emergence of systematic reservoir management in the early 20th century was guided by concepts developed for natural lakes (Miranda 1996). However, we now recognize that reservoirs are different and that reservoirs are not independent aquatic systems inasmuch as they are connected to upstream rivers and streams, the downstream river, other reservoirs in the basin, and the watershed. Reservoir systems exhibit longitudinal patterns both within and among reservoirs. Reservoirs are typically arranged sequentially as elements of an interacting network, filter water collected throughout their watersheds, and form a mosaic of predictable patterns. Traditional approaches to fisheries management such as stocking, regulating harvest, and in-lake habitat management do not always produce desired effects in reservoirs. As a result, managers may expend resources with little benefit to either fish or fishing. Some locally

  12. 松辽盆地南部长岭断陷火山岩岩性岩相特征及其对储层的控制作用%Lithologic and Lithofacies Characteristics of Volcanic Rock and Their Controlling Effects on Reservoirs of Changling Fault Depression in the South of Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    姜雪; 邹华耀; 饶勇; 杨元元

    2009-01-01

    长岭断陷是松辽盆地南部最大的断陷,其深层勘探程度低、油气资源丰富、火山岩分布面积大,是很好的油气储集空间.为了明确长岭断陷层火山岩的分布规律以预测有利的储层,本文通过对火山岩的岩心观察、薄片鉴定、测井资料、二维、三维地震资料的综合分析,提出长岭断陷层火山岩主要发育于火石岭组和营城组,以火山熔岩和火山碎屑岩为主;发育出爆发相、溢流相、火山通道相、侵出相和火山沉积相5种火山岩岩相及11种亚相,其中以爆发相和溢流相为主;长岭断陷深层火山岩主要沿深大断裂呈带状分布.裂隙式和中心式喷发兼有,在垂向上表现为多期次喷发序列的叠置:营城组发育三个火山喷发旋回.统计显示溢流相上部和下部亚相的流纹岩和爆发相热碎屑流亚相的凝灰岩的气孔、溶孔和裂缝发育,储集物性最好.%The Changling fault depression is the largest fault depression in the south of Songliao Basin. The deep formation in the depression with a low exploration degree contains abundant hydrocarbon resources, where volcanic rocks are distributedextensively, as a good reservoir of oil and gasses. According to core observation, thin section identification and integration of well log and 2D/3D seismic data, the Yingcheng formation and Huoshiling formation are rich in volcanic rocks, mainly consisting of lava and pyroclastic rocks. 5 types of volcanic lithofacies and 11 types of volcanic subfacies such as explosive facies, overflow facies, volcanic conduit facies, extrusive facies and eruptive-sedimentary facies can be identified, which are mainly overflow facies and explosive facies. The volcanic rocks in the depression are distributed along big deep faults and superimposed by many times of volcanic eruption in the vertical direction in models of eruption of both central type and fissure type. And three volcanic eruption cycles can be identified in

  13. 准噶尔盆地乌夏地区二叠系风城组云质岩类成因研究%Origin of Dolomitic Reservoir Rock in the Permian Fengcheng Formation in Wu-Xia Area of the Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    朱世发; 朱筱敏; 陶文芳; 刘诗奇; 陈贺贺; 张越迁

    2013-01-01

    The dolomitic rocks of the Permian Fengcheng Formation are formed under special geologic conditions, and are important hydrocarbon reservoir rocks in Wu-Xia area in the Junggar Basin. Data of petrologic characteristics, SEM EDS and stable isotope composition indicate that dolomitizing host rocks are volcaniclassic rocks. Dolomitizing fluids probably came from brine from nearshore and shallow-water lake deposits in the Fengcheng Formation, which formed under arid climatic conditions, and from residual Mg-rich seawater from underlying Jiamuhe Formation and Carboniferous strata. Tuff has a significant content of plagioclase, in which anorthite and labradorite hydrolysis by CO2 can be couple with calcite precipitation. Later, Mg-rich brine percolate and replace calcite of the first stage to precipitate dolostones. The dolomitizing fluid has been driven by the thermal convection flow generated by volcanic eruption. At the same time, the overthrust of the Wu-Xia growth fault have speeded up the flow of deep Mg-rich water upwards, and induced the water to quickly penetrate and horizontally migrate in the strata. Fracture and fault play important role in controlling the formation of dolostone and the distribution of favorable reservoir.%  准噶尔盆地乌夏地区风城组发育的云质岩类是一套特殊成因的、重要的油气储层。岩石学、扫描电镜能谱和稳定同位素分析表明,发生白云岩化作用的母岩是火山凝灰物质,白云岩化的流体来自风城组干旱气候条件下形成的咸化滨浅湖卤水以及下伏佳木河组和石炭系残留的富镁海水。凝灰岩中富含大量的斜长石,其中的富钙长石在二氧化碳参与下水解蚀变,沉淀方解石(即方解石化)。后期富镁卤水渗滤早期形成的方解石,成岩交代形成白云岩。富镁流体运移受火山喷发产生的热流驱动,产生热对流环。同时,乌夏断裂同生逆掩活动加快深层

  14. Thermal recovery of bitumen from carbonate reservoirs: formation damage aspects

    Energy Technology Data Exchange (ETDEWEB)

    Thimm, H.F. [Thimm Petroleum Technologies Inc. (Canada)

    2011-07-01

    In Alberta, about a third of bitumen resources are located in carbonate reservoirs but none of it is considered as a reserve by the Alberta Energy Resources Conservation Board (ERCB). In fact no pilot has been successful in recovering bitumen from carbonate reservoirs due to formation damage problems. Carbonate rock is chemically active at the high temperatures reached in thermal recovery processes, carbon dioxide is generated and carbonate minerals are precipitated. The aim of this paper is to find methods to control the phenomenon. Kinetic and thermodynamic controls were used. Results showed that formation damage is due to aqueous carbon dioxide attacking the reservoir rock. They found that a reduction of the partial pressure of carbon dioxide could inhibit the initial dissolution of rock material by reducing the concentration of aqueous carbon dioxide. A method to overcome the formation damage problem was found and a co-injection of gas and steam process was developed to apply it.

  15. Improved reservoir exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Thomassen, P.R. [IKU Petroleumsforskning A/S, Trondheim (Norway)

    1996-12-31

    This paper deals with reservoir exploitation and it highlights some ideas on how to improve exploitive skills to optimise the recovery of a field. The author looks closer at what needs to be done to optimise the reservoir data and the exploitation tools, and what are the needs of the reservoir production management. 2 refs., 3 figs.

  16. 川东北碳酸岩储层测井资料的几点认识%A few understanding about the well logging data of carbonate rock reservoir in Northeast Sichuan

    Institute of Scientific and Technical Information of China (English)

    王煊

    2012-01-01

    Compared with the traditional sand/shale formation, the formation in Northeast Sichuan is characterized by high resistivity ,low sonic differential time (SDT) and low natural gamma ray (GR). The quality of well log is influenced by many factors, which result in the complexity in reservoir division and fluid property interpretation. On the basis of obser- vation data, the influencing factors of observed values and differences of the well log were analyzed one by one. These influ- encing factors are consist of borehole size, fissure, lithological character, mud filtrate, formation water resistivity, invasion depth, and so on. In addition, the geological application of the crossed dipoles is synthetically expounded.%与传统砂泥岩地层相比,川东北地区地层常以高电阻率、低声波时差、低自然伽玛为特征。影响测井曲线质量的因素很多,由此造成了储层划分和流体性质解释的难度。结合实测资料,对影响曲线测量值和差异的各种因素逐一进行了分析,这些影响因素包括井眼大小、裂缝、岩性、泥浆滤液和地层水电阻率、侵入深度等。并对交叉偶极子的地质应用进行了综合阐述。

  17. Characteristics of volcanic reservoirs and distribution rules of effective reservoirs in the Changling fault depression, Songliao Basin

    Directory of Open Access Journals (Sweden)

    Pujun Wang

    2015-11-01

    Full Text Available In the Songliao Basin, volcanic oil and gas reservoirs are important exploration domains. Based on drilling, logging, and 3D seismic (1495 km2 data, 546 sets of measured physical properties and gas testing productivity of 66 wells in the Changling fault depression, Songliao Basin, eruptive cycles and sub-lithofacies were distinguished after lithologic correction of the 19,384 m volcanic well intervals, so that a quantitative analysis was conducted on the relation between the eruptive cycles, lithologies and lithofacies and the distribution of effective reservoirs. After the relationship was established between lithologies, lithofacies & cycles and reservoir physical properties & oil and gas bearing situations, an analysis was conducted on the characteristics of volcanic reservoirs and the distribution rules of effective reservoirs. It is indicated that 10 eruptive cycles of 3 sections are totally developed in this area, and the effective reservoirs are mainly distributed at the top cycles of eruptive sequences, with those of the 1st and 3rd Members of Yingcheng Formation presenting the best reservoir properties. In this area, there are mainly 11 types of volcanic rocks, among which rhyolite, rhyolitic tuff, rhyolitic tuffo lava and rhyolitic volcanic breccia are the dominant lithologies of effective reservoirs. In the target area are mainly developed 4 volcanic lithofacies (11 sub-lithofacies, among which upper sub-lithofacies of effusive facies and thermal clastic sub-lithofacies of explosion lithofacies are predominant in effective reservoirs. There is an obvious corresponding relationship between the physical properties of volcanic reservoirs and the development degree of effective reservoirs. The distribution of effective reservoirs is controlled by reservoir physical properties, and the formation of effective reservoirs is influenced more by porosity than by permeability. It is concluded that deep volcanic gas exploration presents a good

  18. Petroleum geochemical proxies for reservoir engineering parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, B. [Petroleum Reservoir Group (PRG), Department of Geology and Geophysics, University of Calgary, 2500 University Drive NW, Calgary, Alberta (Canada); Lager, A. [NRG: School of Civil Engineering and Geosciences, Drummond Building, The University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Potter, D.K.; Buckman, J.O. [Institute of Petroleum Engineering, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS (United Kingdom); Larter, S.R. [Petroleum Reservoir Group (PRG), Department of Geology and Geophysics, University of Calgary, 2500 University Drive NW, Calgary, Alberta (Canada); NRG: School of Civil Engineering and Geosciences, Drummond Building, The University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2007-09-15

    The prediction of fluid flow behaviour in petroleum reservoirs is influenced by the physical and chemical processes active in interacting crude oil/brine/rock systems. It is usually not possible to assess these complex systems directly so proxies for molecular scale behaviour are needed. By their very nature, polar non-hydrocarbons are sensitive to fluid-rock interactions, and if properly exploited they may be utilised as proxies for describing reservoir engineering properties (e.g. wettability) that are also sensitive to fluid-rock interactions. We have identified a group of aromatic oxygen (alkylphenols and alkylfluorenones) and aromatic nitrogen (alkylcarbazoles) compounds present in petroleum that appear to respond to variations in fluid-rock properties. Here we describe the chemical and physical changes in a series of core samples obtained from North Sea reservoirs. A number of petrophysical parameters displayed strong correlations with polar non-hydrocarbon occurrence. For example, deflections in gamma ray logs in response to clay content in a coarsening upwards sandstone unit also showed similar deflections from a number of geochemical logs. A core-flood experiment was designed to monitor the chemical and physical changes during oil migration in a siltstone core. Following completion of the core-flood experiment, Environmental Scanning Electron Microscopy (ESEM) analysis of core samples indicated hydrophilic and hydrophobic surface tendencies grading throughout the core. The distributions of polar non-hydrocarbons (e.g. C{sub 0}-C{sub 3}-phenols) appear to correspond closely to the observed wettability alteration. The results confirm the potential for developing proxies for fluid-rock interactions through monitoring the surface active compounds present in the polar non-hydrocarbon fraction of petroleum. (author)

  19. Status of Wheeler Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

  20. Status of Cherokee Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  1. Status of Cherokee Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  2. Distribution and characteristics of volcanic reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    HUANG Yulong; WANG Pujun; CHEN Shuming

    2009-01-01

    About forty productive oil/gas fields hosted in volcanic reservoirs have been found since 1957 in fourteen basins of China. They can be simply subdivided into two groups, the east and the west. Reservoir volcanic rocks of the east group are predominantly composed of Late Jurassic to Early Cretaceous rhyolite and Tertiary basalt, preferred being considered as rift type volcanics developed in the circum-Pacific tectonic regime. Those of the west are Permo-Carboniferous intermediate/basic volcanic rocks, being island-arc type ones developed in paleo-Asian Ocean tectonic regime.

  3. Using reservoir engineering data to solve geological ambiguities : a case study of one of the Iranian carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Kord, S. [National Iranian South Oil Co. (Iran, Islamic Republic of)

    2006-07-01

    A fractured carbonate reservoir in southwest Iran was studied with reference to reserve estimation, risk analysis, material balance and recovery factor. The 40 km long and 4 km wide reservoir consists of 2 parts with crest depths of 3780 and 3749 mss respectively. The eastern part is smaller and more productive than the western part which has high water saturation and absolutely no production. Economic production from the reservoir began in 1977. By 2004, the cumulative production had reached 12.064 MMSTB. Of the 6 wells drilled, only 2 wells in the eastern part are productive. This study addressed the main uncertainty of whether the 2 parts of the reservoir are sealed or not. The reservoir is under-saturated but the current pressure is near saturation pressure. The reservoir is divided into the following 4 zones: zones 1 and 2 are productive and consist mainly of carbonate rocks; zone 3 has thin beds of sand and shale; and, zone 4 consists of layers of carbonate, shale, marn, and dolomite. Although there are no faults, mud loss suggests that the reservoir has hairline fractures. Oil in place and reserves were estimated for both parts based on calculated reservoir engineering parameters. Material balance calculations were then performed to analyze and simulate the reservoir. The communication between the 2 parts of the reservoir were examined according to core analysis, rock type, fluid characterization, pressure analysis, water-oil contacts, production history and petrophysical evaluations. The porosity was found to be the same in both parts, but the water saturation and net to gross ratios were different between the eastern and western parts. The petrophysical evaluation revealed that there is no communication between the two parts of the reservoir. 4 refs., 2 figs., 2 appendices.

  4. Reservoir characterization of hydraulic flow units in heavy-oil reservoirs at Petromonagas, eastern Orinoco belt, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Merletti, G.D.; Hewitt, N.; Barrios, F.; Vega, V.; Carias, J. [BP Exploration, Houston, TX (United States); Bueno, J.C.; Lopez, L. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of)

    2009-07-01

    An accurate integrated reservoir description is necessary in extra-heavy oil prospects where pore throat geometries are the ultimate control on hydrocarbon primary recovery. The key element in producing accurate oil reservoir descriptions and improving productivity is to determine relationships between core-derived pore-throat parameters and log-derived macroscopic attributes. This paper described the use of the flow zone indicator technique (FZI) to identify hydraulic units within depositional facies. It focused on a petrophysical analysis aimed at improving the description of reservoir sandstones containing heavy or extra heavy oil in the eastern Orinoco belt in Venezuela. The Petromonagas license area contains large volumes of crude oil in-place with an API gravity of 8. Production comes primarily from the lowermost stratigraphic unit of the Oficina Formation, the Miocene Morichal Member. Facies analysis has revealed various depositional settings and core measurements depict a wide range in reservoir quality within specific depositional facies. The reservoir is divided into 4 different rock qualities and 5 associated non-reservoir rocks. The use of the FZI technique provides a better understanding of the relationship between petrophysical rock types and depositional facies. 4 refs., 4 tabs., 8 figs.

  5. Brine and Gas Flow Patterns Between Excavated Areas and Disturbed Rock Zone in the 1996 Performance Assessment for the Waste Isolation Pilot Plant for a Single Drilling Intrusion that Penetrates Repository and Castile Brine Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    ECONOMY,KATHLEEN M.; HELTON,JON CRAIG; VAUGHN,PALMER

    1999-10-01

    The Waste Isolation Pilot Plant (WIPP), which is located in southeastern New Mexico, is being developed for the geologic disposal of transuranic (TRU) waste by the U.S. Department of Energy (DOE). Waste disposal will take place in panels excavated in a bedded salt formation approximately 2000 ft (610 m) below the land surface. The BRAGFLO computer program which solves a system of nonlinear partial differential equations for two-phase flow, was used to investigate brine and gas flow patterns in the vicinity of the repository for the 1996 WIPP performance assessment (PA). The present study examines the implications of modeling assumptions used in conjunction with BRAGFLO in the 1996 WIPP PA that affect brine and gas flow patterns involving two waste regions in the repository (i.e., a single waste panel and the remaining nine waste panels), a disturbed rock zone (DRZ) that lies just above and below these two regions, and a borehole that penetrates the single waste panel and a brine pocket below this panel. The two waste regions are separated by a panel closure. The following insights were obtained from this study. First, the impediment to flow between the two waste regions provided by the panel closure model is reduced due to the permeable and areally extensive nature of the DRZ adopted in the 1996 WIPP PA, which results in the DRZ becoming an effective pathway for gas and brine movement around the panel closures and thus between the two waste regions. Brine and gas flow between the two waste regions via the DRZ causes pressures between the two to equilibrate rapidly, with the result that processes in the intruded waste panel are not isolated from the rest of the repository. Second, the connection between intruded and unintruded waste panels provided by the DRZ increases the time required for repository pressures to equilibrate with the overlying and/or underlying units subsequent to a drilling intrusion. Third, the large and areally extensive DRZ void volumes is a

  6. Reservoir Characteristic of Famennian Deposits of the Solikamsk Depression

    Directory of Open Access Journals (Sweden)

    A. V. Plyusnin

    2015-06-01

    Full Text Available The article describes the reservoir rock properties of Famennian (Late Devonian reef carbonate strata obtained by core study at boreholes № 1-4 of the Sukharev oil field. Based on the results of detailed study of lithological features of productive strata, authors defined the structural types and composed their description. The characteristics of the porosity and permeability of oil-bearing beds were shown. In a result of studies, the structure and main lithotypes of Famennian portion of reservoir were determined that allowed predicting the spatial distribution of reservoir properties within oilfield area.

  7. Reservoir-forming age and its exploration significance to stratigraphic reservoirs in southern Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Despite many studies concerning the forming age, evolution characteristics and the age of petroleum charging in the Fuxin upheaval of southern Songliao Basin, no consensus has been reached so far. This paper presents the first K-Ar dating of autogenetic illite from stratigraphic petroleum reservoirs in the Fuyu oil layer of the Fuxin upheaval belt. Isotopic test and age calculation were carried out based on the separation and purification of illite mineral, X-diffraction analysis and the detection of scanning electron microscopy. The evolution characteristics of structure, sedimentation, reservoir-forming about the Fuxin upheaval belt were interpreted in terms of the synthetical analysis of "six-type geological history" evolution in southern Songliao Basin. The geologic background of petroleum evolution and reservoir formation are similar in the entire central depression region of southern Songliao Basin. The Changling sag and the Fuxin upheaval belt brought about obvious upheaval-sag separation after the hydrocarbon-generation peak of K2qn1 and the main reservoir-forming period of the Fuyu oil layer, namely reservoir-forming happened before the Fuxin upheaval belt extensively raised. The reservoirs have three characteristics: the hydrocarbon source rock above the reservoir, the oil source in the locality, and the vertical migration. The geological cognition is corrected, that is, oil source came from the Changling sag and migrated from the side direction. The bulk process of petroleum charging in the stratigraphic hydrocarbon reservoirs in the Fuxin upheaval belt of southern Songliao Basin is determined according to the isotopic age of autogenetic illite in combination with the method of fluid inclusions. The cognition is helpful to exactly evaluate the resource potential and exploration direction in the Fuxin upheaval belt, Changling sag and their peripheral areas. The present results indicate that the combination of the two methods (the K-Ar dating of

  8. Laboratory investigation of novel oil recovery method for carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Yousef, A.A.; Al-Saleh, S.; Al-Kaabi, A.; Al-Jawfi, M. [Saudi Aramco, Riyadh (Saudi Arabia)

    2010-07-01

    This paper described a core flooding laboratory study conducted using composite rock samples from a carbonate reservoir. The aim of the study was to investigate the impact of salinity and ionic composition on oil, brine and rock interactions. Experimental parameters and procedures were designed to replicate reservoir conditions and current field injection practices. Results of the study demonstrated that alterations in the salinity and ionic composition of injected water can have a significant impact on the wettability of the rock surface. Nuclear magnetic resonance (NMR) studies confirmed that injecting different salinity slugs of seawater in carbonate core samples can cause a significant alteration in the surface charges of the rock, and lead to increased interactions with water molecules. The constant reduction of pressure drop across the composite cores with the injection of different diluted versions of water also provided proof of brine, oil and rock alterations. Results of the study indicated that the driving mechanism for waterflooding recovery processes is wettability alteration, which can be triggered by alterations in carbonate rock surface charges, and improvements in the connectivity between rock pore systems that coexist in carbonate rock samples. 41 refs., 8 tabs., 16 figs.

  9. Stability of Fluorosurfactant Adsorption on Mineral Surface for Water Removal in Tight Gas Reservoirs

    OpenAIRE

    Lijun You; Wanchun Zhang; Yili Kang; Zhangxin Chen; Xuefen Liu

    2015-01-01

    Long-term effectiveness of rock wettability alteration for water removal during gas production from tight reservoir depends on the surfactant adsorption on the pore surface of a reservoir. This paper selected typical cationic fluorosurfactant FW-134 as an example and took advantage of Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscope (AFM) to investigate its adsorption stability on the rock mineral surface under the oscillation...

  10. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  11. Reservoir assessment of the Nubian sandstone reservoir in South Central Gulf of Suez, Egypt

    Science.gov (United States)

    El-Gendy, Nader; Barakat, Moataz; Abdallah, Hamed

    2017-05-01

    The Gulf of Suez is considered as one of the most important petroleum provinces in Egypt and contains the Saqqara and Edfu oil fields located in the South Central portion of the Gulf of Suez. The Nubian sandstone reservoir in the Gulf of Suez basin is well known for its great capability to store and produce large volumes of hydrocarbons. The Nubian sandstone overlies basement rocks throughout most of the Gulf of Suez region. It consists of a sequence of sandstones and shales of Paleozoic to Cretaceous age. The Nubian sandstone intersected in most wells has excellent reservoir characteristics. Its porosity is controlled by sedimentation style and diagenesis. The cementation materials are mainly kaolinite and quartz overgrowths. The permeability of the Nubian sandstone is mainly controlled by grain size, sorting, porosity and clay content especially kaolinite and decreases with increase of kaolinite. The permeability of the Nubian Sandstone is evaluated using the Nuclear Magnetic Resonance (NMR technology) and formation pressure data in addition to the conventional logs and the results were calibrated using core data. In this work, the Nubian sandstone was investigated and evaluated using complete suites of conventional and advanced logging techniques to understand its reservoir characteristics which have impact on economics of oil recovery. The Nubian reservoir has a complicated wettability nature which affects the petrophysical evaluation and reservoir productivity. So, understanding the reservoir wettability is very important for managing well performance, productivity and oil recovery.

  12. Relation between facies, diagenesis, and reservoir quality of Rotliegende reservoirs in north Germany

    Energy Technology Data Exchange (ETDEWEB)

    David, F.; Gast, R.; Kraft, T. (BEB Erdgas Erdol GmbH, Hannover (Germany))

    1993-09-01

    In north Germany, the majority of Rotliegende gas fields is confined to an approximately 50 km-wide east-west-orientated belt, which is situated on the gently north-dipping flank of the southern Permian basin. Approximately 400 billion m[sup 3] of natural gas has been found in Rotliegende reservoir sandstones with average porosities of depths ranging from 3500 to 5000 m. Rotliegende deposition was controlled by the Autunian paleo-relief, and arid climate and cyclic transgressions of the desert lake. In general, wadis and large dunefields occur in the hinterland, sebkhas with small isolate dunes and shorelines define the coastal area, and a desert lake occurs to the north. The sandstones deposited in large dunefields contain only minor amounts of illite, anhydrite, and calcite and form good reservoirs. In contrast, the small dunes formed in the sebkha areas were affected by fluctuations of the desert lake groundwaters, causing the infiltration of detrital clay and precipitation of gypsum and calcite. These cements were transformed to illite, anhydrite, and calcite-II during later diagenesis, leading to a significant reduction of the reservoir quality. The best reservoirs occur in the shoreline sandstones because porosity and permeability were preserved by early magnesium-chlorite diagenesis. Since facies controls diagenesis and consequently reservoir quality, mapping of facies also indicates the distribution of reservoir and nonreservoir rocks. This information is used to identify play area and to interpret and calibrate three-dimensional seismic data.

  13. Integrated reservoir interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Caamano, Ed; Dickerman, Ken; Thornton, Mick (Conoco Indonesia Inc., Jakarta (Indonesia)); Corbett, Chip; Douglas, David; Schultz, Phil (GeoQuest, Houston, TX (United States)); Gir, Roopa; Nicholson, Barry (GeoQuest, Jakarta (Indonesia)); Martono, Dwi; Padmono, Joko; Novias; Kiagus; Suroso, Sigit (Pertamina Sumbagut, Brandan, North Sumatra (Indonesia)); Mathieu, Gilles (Etudes et Productions Schlumberger, Clamart (France)); Yan, Zhao (China National Petroleum Company, Beijing (China))

    1994-07-01

    Improved reservoir management often relies on linking a variety of application software that helps geoscientists handle, visualize and interpret massive amounts of diverse data. The goal is to obtain the best possible reservoir model so its behavior can be understood and optimized. But diverse application software creates specialty niches and discourages integrated interpretation. A description is given of a new reservoir management package that covers all required functionalities and encourages the geologist, geophysicist, petrophysicist and reservoir engineer to embrace the integrated approach. Case studies are included in the article. 21 figs., 13 refs.

  14. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Annual technical progress report, June 13, 1996--June 12, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Nevans, J.W.; Pregger, B. [Fina Oil and Chemical Co., Midland, TX (United States); Blasingame, T.; Doublet, L. [Texas A and M Univ., College Station, TX (United States); Freeman, G.; Callard, J. [Univ. of Tulsa, OK (United States); Moore, D. [Scientific Software, Inc. (United States); Davies, D.; Vessell, R. [David K. Davies and Associates (United States)

    1997-08-01

    Infill drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, does not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations. The purpose of this project is to demonstrate the application of advanced secondary recovery technologies to remedy producibility problems in typical shallow shelf carbonate reservoirs of the Permian Basin, Texas. Typical problems include poor sweep efficiency, poor balancing of injection and production rates, and completion techniques that are inadequate for optimal production and injection.

  15. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drillings. Annual technical progress report, June 13, 1996 to June 12, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Nevans, Jerry W.; Blasingame, Tom; Doublet, Louis; Kelkar, Mohan; Freeman, George; Callard, Jeff; Moore, David; Davies, David; Vessell, Richard; Pregger, Brian; Dixon, Bill

    1999-04-27

    Infill drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, does not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations. Other technologies, such as inter-well injection tracers and magnetic flow conditioners, can also aid in the efficient evaluation and operation of both injection and producing wells. The purpose of this project was to demonstrate useful and cost effective methods of exploitation of the shallow shelf carbonate reservoirs of the Permian Basin located in West Texas.

  16. Feasibility study of sedimentary enhanced geothermal systems using reservoir simulation

    Science.gov (United States)

    Cho, Jae Kyoung

    The objective of this research is to evaluate the preliminary feasibility of commercial geothermal projects, from a sedimentary reservoir with low permeability that requires productivity enhancement, using numerical reservoir simulation. The performance of a sedimentary geothermal reservoir is investigated in terms of reservoir hydraulics and thermal evolution. To build a reliable benchmark for simulation study, validation of the numerical reservoir model with respect to an analytical model is presented, and the process to achieve an acceptable match between the numerical and analytical solutions is described. The analytical model used in this study is based on the work of Gringarten (1978), which consists of a conceptual geothermal reservoir, considering an injection and production well doublet in a homogeneous porous media. A commercial thermal reservoir simulator (STARS from Computer Modeling Group, CMG) is used in this work for numerical modeling. In order to reproduce the analytical model results, the numerical simulation model is modified to include the same assumptions of the analytical model. Simulation model parameters that make the numerical results deviate from the analytical solution, such as the grid block size, time step and no-flow boundary are identified and investigated. An analytical tracer test model proposed by Shook (2000) is numerically modeled. This model allows us to predict the time when the temperature of the produced water decreases by capturing a tracer component at production well. Reservoir simulation models with different porosity and permeability distribution are tested to see the effects of reservoir inhomogeneity and anisotropy. In particular, premature thermal breakthrough due to the presence of high permeability streak in a reservoir model is simulated. In an effort to apply the knowledge we obtained from the analytical solutions, the effects of reservoir rock and water properties, as a function of pressure and temperature, are

  17. A new biostratigraphical tool for reservoir characterisation and well correlation in permo-carboniferous sandstones

    NARCIS (Netherlands)

    Garming, J.F.L.; Cremer, H.; Verreussel, R.M.C.H.; Guasti, E.; Abbink, O.A.

    2010-01-01

    Permo-Carboniferous sandstones are important reservoir rocks for natural gas in the Southern North Sea basin. This is a mature area which makes tools for reservoir characterization and well to well correlation important for field optimalisation and ongoing exploration activities. Within the Permo-Ca

  18. Application of the new Gassmann theory in seismic modeling of selected gas reservoirs, offshore Netherlands

    NARCIS (Netherlands)

    Auduson, A.E.

    2013-01-01

    In the Southern North Sea, Buntsandstein reservoirs which, can be gas- or water-bearing, frequently contain solid (salt) in the pores spaces. Recent literatures on extension of the Gassmann equation investigate the substitution of fluids and solids in the pore space of reservoir rock. Conventional s

  19. Ray-based stochastic inversion of pre-stack seismic data for improved reservoir characterisation

    NARCIS (Netherlands)

    van der Burg, D.W.

    2007-01-01

    To estimate rock and pore-fluid properties of oil and gas reservoirs in the subsurface, techniques can be used that invert seismic data. Hereby, the detailed information about the reservoir that is available at well locations, such as the thickness and porosity of individual layers, is extrapolated

  20. Improving recovery efficiency of water-drive channel sandstone reservoir by drilling wells laterally

    Energy Technology Data Exchange (ETDEWEB)

    Zhiguo, F.; Quinglong, D.; Pingshi, Z.; Bingyu, J.; Weigang, L. [Research Institute of Exploration and Development, Daqing (China)

    1998-12-31

    Example of drilling a horizontal well in reservoir rock of only four meter thick by using existing casing pipe of low efficiency vertical wells to induce production in the top remaining reservoir is described. The experience shows that drilling horizontal wells laterally in thin bodies of sandstone reservoirs and improve their productivity is a feasible proposition. Productivity will still be low, but it can be improved by well stimulation. 3 refs., 3 figs.

  1. Geothermal reservoir engineering. 7. Reservoir simulator; Chinetsu choryuso kogaku. 7. Choryuso simulator

    Energy Technology Data Exchange (ETDEWEB)

    Ishido, T. [Geological Survey of Japan, Tsukuba (Japan)

    1998-09-15

    In modeling for actual geothermal reservoirs, the following basic functions are required for general-purpose numerical reservoir simulators: (1) Applicability to all hydrothermal single phase flow, steam single phase flow and hydrothermal-steam two phase flow, (2) Consideration of the effect of temperature and pressure on fluid physical properties such as coefficient of viscosity, (3) Assumption of Darcy`s law for flow every phase, (4) Assumption of heterogeneous properties of rocks, (5) Applicability to both transfer and convection of heat flow, and (6) Consideration of both mass and energy conservation laws. On the reservoir simulators, this paper outlines a dominant equation and its digitizing method and digitized solution, evaluation of the simulators, optional functions, and others. Numerical dispersion unavoidable for an advection diffusion problem is also explained. In addition, the basic equation and applications of a bore hole two-phase flow simulator are presented. 21 refs., 9 figs.

  2. Oil exploration. Oil reservoir engineering; Sekiyu no kaihatsu. Choryuso kogaku

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, H. [Teikoku Oil Co. Ltd., Tokyo (Japan)

    1998-09-01

    This study is to estimate the amount of oil/gas economically producible and to discuss the increase of the amount. The reservoir rock is stuffed with rock particles, and there are impermeable and dense rocks called cap rock on the side wall and top board. Since the size of void of the reservoir is very small, the volume which oil can actually occupy largely decreases because of the existence of surface tension and water film (20-40% of the volume is occupied by water). The rate of the fluid occupying in reservoir space is called the fluid saturation rate. The primitive reserve is a static volume, but the minable reserve, which is related to economical efficiency, is a dynamic volume which changes according to conditions such as the technical progress. To predict a minable reserve is to predict a production amount under a developmental plan, estimate an income, and find out the time of disposal of the oil/gas field (economical limit). To ask for a certain level of accuracy, it is indispensable to simulate the reservoir. To add an element of time to the material balance, the equation of flow including the permeability rate is solved. The paper also described measures to increase minable reserves

  3. CERN Rocks

    CERN Document Server

    2004-01-01

    The 15th CERN Hardronic Festival took place on 17 July on the terrace of Rest 3 (Prévessin). Over 1000 people, from CERN and other International Organizations, came to enjoy the warm summer night, and to watch the best of the World's High Energy music. Jazz, rock, pop, country, metal, blues, funk and punk blasted out from 9 bands from the CERN Musiclub and Jazz club, alternating on two stages in a non-stop show.  The night reached its hottest point when The Canettes Blues Band got everybody dancing to sixties R&B tunes (pictured). Meanwhile, the bars and food vans were working at full capacity, under the expert management of the CERN Softball club, who were at the same time running a Softball tournament in the adjacent "Higgs Field". The Hardronic Festival is the main yearly CERN music event, and it is organized with the support of the Staff Association and the CERN Administration.

  4. Reservoir Engineering Management Program

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Schwarz, W.J.

    1977-12-14

    The Reservoir Engineering Management Program being conducted at Lawrence Berkeley Laboratory includes two major tasks: 1) the continuation of support to geothermal reservoir engineering related work, started under the NSF-RANN program and transferred to ERDA at the time of its formation; 2) the development and subsequent implementation of a broad plan for support of research in topics related to the exploitation of geothermal reservoirs. This plan is now known as the GREMP plan. Both the NSF-RANN legacies and GREMP are in direct support of the DOE/DGE mission in general and the goals of the Resource and Technology/Resource Exploitation and Assessment Branch in particular. These goals are to determine the magnitude and distribution of geothermal resources and reduce risk in their exploitation through improved understanding of generically different reservoir types. These goals are to be accomplished by: 1) the creation of a large data base about geothermal reservoirs, 2) improved tools and methods for gathering data on geothermal reservoirs, and 3) modeling of reservoirs and utilization options. The NSF legacies are more research and training oriented, and the GREMP is geared primarily to the practical development of the geothermal reservoirs. 2 tabs., 3 figs.

  5. Dynamic reservoir well interaction

    NARCIS (Netherlands)

    Sturm, W.L.; Belfroid, S.P.C.; Wolfswinkel, O. van; Peters, M.C.A.M.; Verhelst, F.J.P.C.M.

    2004-01-01

    In order to develop smart well control systems for unstable oil wells, realistic modeling of the dynamics of the well is essential. Most dynamic well models use a semi-steady state inflow model to describe the inflow of oil and gas from the reservoir. On the other hand, reservoir models use steady s

  6. Geothermal reservoir engineering research

    Science.gov (United States)

    Ramey, H. J., Jr.; Kruger, P.; Brigham, W. E.; London, A. L.

    1974-01-01

    The Stanford University research program on the study of stimulation and reservoir engineering of geothermal resources commenced as an interdisciplinary program in September, 1972. The broad objectives of this program have been: (1) the development of experimental and computational data to evaluate the optimum performance of fracture-stimulated geothermal reservoirs; (2) the development of a geothermal reservoir model to evaluate important thermophysical, hydrodynamic, and chemical parameters based on fluid-energy-volume balances as part of standard reservoir engineering practice; and (3) the construction of a laboratory model of an explosion-produced chimney to obtain experimental data on the processes of in-place boiling, moving flash fronts, and two-phase flow in porous and fractured hydrothermal reservoirs.

  7. Modeling vapor dominated geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Marconcini, R.; McEdwards, D.; Neri, G.; Ruffilli, C.; Schroeder, R.; Weres, O.; Witherspoon, P.

    1977-09-12

    The unresolved questions with regard to vapor-dominated reservoir production and longevity are reviewed. The simulation of reservoir behavior and the LBL computer program are discussed. The geology of Serrazzano geothermal field and its reservoir simulation are described. (MHR)

  8. Seismic and Rockphysics Diagnostics of Multiscale Reservoir Textures

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2005-07-01

    This final technical report summarizes the results of the work done in this project. The main objective was to quantify rock microstructures and their effects in terms of elastic impedances in order to quantify the seismic signatures of microstructures. Acoustic microscopy and ultrasonic measurements were used to quantify microstructures and their effects on elastic impedances in sands and shales. The project led to the development of technologies for quantitatively interpreting rock microstructure images, understanding the effects of sorting, compaction and stratification in sediments, and linking elastic data with geologic models to estimate reservoir properties. For the public, ultimately, better technologies for reservoir characterization translates to better reservoir development, reduced risks, and hence reduced energy costs.

  9. 4D seismic reservoir characterization, integrated with geo-mechanical modelling

    NARCIS (Netherlands)

    Angelov, P. V.

    2009-01-01

    Hydrocarbon production induces time-lapse changes in the seismic attributes (travel time and amplitude) both at the level of the producing reservoir and in the surrounding rock. The detected time-lapse changes in the seismic are induced from the changes in the petrophysical properties of the rock,

  10. 4D seismic reservoir characterization, integrated with geo-mechanical modelling

    NARCIS (Netherlands)

    Angelov, P. V.

    2009-01-01

    Hydrocarbon production induces time-lapse changes in the seismic attributes (travel time and amplitude) both at the level of the producing reservoir and in the surrounding rock. The detected time-lapse changes in the seismic are induced from the changes in the petrophysical properties of the rock, i

  11. Carbonate reservoir characterization. A geologic-engineering analysis. Part 2

    Energy Technology Data Exchange (ETDEWEB)

    Chilingarian, G.V. [School of Engineering, University of Southern California, Los Angeles (United States); Mazzullo, S.J. [Geology Department, Wichita State University, Wichita (United States); Rieke, H.H. [Petroleum Engineering Department, University of Southwestern Louisiana, Lafayette (United States); Dominguez, G.C.; Samaniego, F. [eds.

    1996-12-31

    This second volume on carbonate reservoirs completes the two-volume treatise on this important topic to petroleum engineers and geologists. The two volumes form a complete and modern reference work to the properties and production behavior of carbonate petroleum reservoirs. This volume contains valuable glossaries to geologic and petroleum engineering terms providing exact definitions for writers and speakers. Professors will find a useful appendix devoted to questions and problems that can be used for teaching assignments as well as a guide for lecture development. In addition, there is a chapter devoted to core analysis of carbonate rocks which is ideal for laboratory instruction. Managers and production engineers will find a review of the latest laboratory technology for carbonate formation evaluation in the chapter on core analysis. The modern classification of carbonate rocks is presented with petroleum production performance and overall characterization using seismic and well test analyses. Separate chapters are devoted to the important naturally fractured and chalk reservoirs. Throughout the book, the emphasis is on formation evaluation and performance. The importance of carbonate reservoirs lies in the fact that they contain as much as 50% of the total petroleum reserves of the world. This is sometimes masked by the uniquely different properties and production performance characteristics of carbonate reservoirs because of their heterogeneity and the immense diversity that exists among them. This two-volume treatise brings together the wide variety of approaches to the study of carbonate reservoirs and, therefore, will fit the needs of managers, engineers, geologists and teachers. figs., tabs., refs.

  12. Potential for hot-dry-rock geothermal resources: Experimental results

    Science.gov (United States)

    Rowley, J. C.; Heiken, G.; Murphy, H. D.; Kuriyagawa, M.

    Hot dry rock (HDR) contains insufficient permeability and fluid for natural hydrothermal development, but water pumped in a circulation loop through a HDR reservoir (hydraulically fractured between two drill holes) is being tested and evaluated. The formation of such in situ heat transfer systems, and subsequent testing of the man-made geothermal reservoirs in the Jemez volcanic field, New Mexico have already indicated the technical feasibility of the hot dry rock (HDR) geothermal concept. Documented production history and heat-extraction data obtained during the period from 1978 to 1980 have confirmed heat transfer, low water loss, and predictable thermal drawdown models for the HDR systems. During a nine month test of closed-loop heat extraction operations, 15 x 10 to the 6th power kWh of thermal energy were produced. The effective heat-transfer area and volume of the reservoir increased due to secondary fracturing caused by thermal contraction of the reservoir rock, and sustained pressurization. Drilling, fracturing, and testing of a larger, hotter reservoir system is now underway on a HDR geothermal reservoir of commercial size.

  13. Rock Physics of Geologic Carbon Sequestration/Storage

    Energy Technology Data Exchange (ETDEWEB)

    Dvorkin, Jack; Mavko, Gary

    2013-05-31

    This report covers the results of developing the rock physics theory of the effects of CO{sub 2} injection and storage in a host reservoir on the rock's elastic properties and the resulting seismic signatures (reflections) observed during sequestration and storage. Specific topics addressed are: (a) how the elastic properties and attenuation vary versus CO{sub 2} saturation in the reservoir during injection and subsequent distribution of CO{sub 2} in the reservoir; (b) what are the combined effects of saturation and pore pressure on the elastic properties; and (c) what are the combined effects of saturation and rock fabric alteration on the elastic properties. The main new results are (a) development and application of the capillary pressure equilibrium theory to forecasting the elastic properties as a function of CO{sub 2} saturation; (b) a new method of applying this theory to well data; and (c) combining this theory with other effects of CO{sub 2} injection on the rock frame, including the effects of pore pressure and rock fabric alteration. An important result is translating these elastic changes into synthetic seismic responses, specifically, the amplitude-versus-offset (AVO) response depending on saturation as well as reservoir and seal type. As planned, three graduate students participated in this work and, as a result, received scientific and technical training required should they choose to work in the area of monitoring and quantifying CO{sub 2} sequestration.

  14. Experimentally determined rock-fluid interactions applicable to a natural hot dry rock geothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Charles, R.W.; Holley, C.E. Jr.; Tester, J.W.; Blatz, L.A.; Grigsby, C.O.

    1980-02-01

    The Los Alamos Scientific Laboratory is pursuing laboratory and field experiments in the development of the Hot Dry Rock concept of geothermal energy. The field program consists of experiments in a hydraulically fractured region of low permeability in which hot rock is intercepted by two wellbores. These experiments are designed to test reservoir engineering parameters such as: heat extraction rates, water loss rates, flow characteristics including impedance and buoyancy, seismic activity and fluid chemistry. Laboratory experiments have been designed to provide information on the mineral reactivity which may be encountered in the field program. Two experimental circulation systems have been built to study the rates of dissolution and alteration in dynamic flow. Solubility studies have been done in agitated systems. To date, pure minerals, samples of the granodiorite from the actual reservoir and Tijeras Canyon granite have been reacted with distilled water and various solutions of NaCl, NaOH, and Na/sub 2/CO/sub 3/. The results of these experimental systems are compared to observations made in field experiments done in a hot dry rock reservoir at a depth of approximately 3 km with initial rock temperatures of 150 to 200/sup 0/C.

  15. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20110887 Chen Yong(College of Geo-Resources and Information,China University of Petroleum,Qingdao 266555,China);Ge Yunjin Experimental Study on the Modes of Hydrocarbon-Bearing Inclusion Trapped in Carbonate Rock Reservoirs(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,29(3),2010,p.217-220,1 illus.,16 refs.,with English abstract)Key words:petroleum products,organic inclusion,carbonates20110888 Cheng Zhizhong(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China);Gu Tiexin Preparation of Nine Iron Ore Reference Materials of GFe-1~GFe-9(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,29(3),2010,p.305-308,5 tables,13 refs.)Key words:iron ores,type specimens Nine standard reference iron ore samples of GFe-1~GFe-9 were developed.The concentrations of TFe of the samples ranged from 20.17% to 66.87%,which covered a wide iron concentration range from concentrated iron ore powder to poor iron ores and can meet the needs for iron ore exploration and ore-dressing.Powder XRF technique was used for homogeneity test and the analytical results indicated that all elements tested were in good homogeneity.

  16. Mathematical simulation of oil reservoir properties

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, A. [Instituto Politecnico Nacional (SEPI-ESQIE-UPALM-IPN), Unidad Profesional Zacatenco, Laboratorio de Analisis Met., Edif. ' Z' y Edif. 6 planta baja., Mexico City c.p. 07300 (Mexico)], E-mail: adalop123@mailbanamex.com; Romero, A.; Chavez, F. [Instituto Politecnico Nacional (SEPI-ESQIE-UPALM-IPN), Unidad Profesional Zacatenco, Laboratorio de Analisis Met., Edif. ' Z' y Edif. 6 planta baja., Mexico City c.p. 07300 (Mexico); Carrillo, F. [Instituto Politecnico Nacional (CICATA-IPN, Altamira Tamaulipas) (Mexico); Lopez, S. [Instituto Mexicano del Petroleo - Molecular Engineering Researcher (Mexico)

    2008-11-15

    The study and computational representation of porous media properties are very important for many industries where problems of fluid flow, percolation phenomena and liquid movement and stagnation are involved, for example, in building constructions, ore processing, chemical industries, mining, corrosion sciences, etc. Nevertheless, these kinds of processes present a noneasy behavior to be predicted and mathematical models must include statistical analysis, fractal and/or stochastic procedures to do it. This work shows the characterization of sandstone berea core samples which can be found as a porous media (PM) in natural oil reservoirs, rock formations, etc. and the development of a mathematical algorithm for simulating the anisotropic characteristics of a PM based on a stochastic distribution of some of their most important properties like porosity, permeability, pressure and saturation. Finally a stochastic process is used again to simulated the topography of an oil reservoir.

  17. Pore structure effect on reservoir electrical properties and well logging evaluation

    Institute of Scientific and Technical Information of China (English)

    Bian Huan-Lin; Guan Ju; Mao Zhi-Qiang; Ju Xiao-Dong; Han Gui-Qing

    2014-01-01

    The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reservoir with different pore structure characteristics to show that the complexity of pore structure had a significant effect on the effective porosity and permeability regardless of geological factors responsible for the formation of pore structure. Moreover,, the distribution and content of conductive fluids in the reservoir varies dramatically owing to pore structure differences, which also induces resistivity variations in reservoir rocks. Hence, the origin of low-resistivity hydrocarbon-bearing zones, except for those with conductive matrix and mud filtrate invasion, is attributed to the complexity of the pore structures. Consequently, reservoir-specific evaluation models, parameters, and criteria should be chosen for resistivity log interpretation to make a reliable evaluation of reservoir quality and fluids.

  18. Rollerjaw Rock Crusher

    Science.gov (United States)

    Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

    2009-01-01

    The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

  19. Reservoir-on-a-chip (ROC): a new paradigm in reservoir engineering.

    Science.gov (United States)

    Gunda, Naga Siva Kumar; Bera, Bijoyendra; Karadimitriou, Nikolaos K; Mitra, Sushanta K; Hassanizadeh, S Majid

    2011-11-21

    In this study, we design a microfluidic chip, which represents the pore structure of a naturally occurring oil-bearing reservoir rock. The pore-network has been etched in a silicon substrate and bonded with a glass covering layer to make a complete microfluidic chip, which is termed as 'Reservoir-on-a-chip' (ROC). Here we report, for the first time, the ability to perform traditional waterflooding experiments in a ROC. Oil is kept as the resident phase in the ROC, and waterflooding is performed to displace the oil phase from the network. The flow visualization provides specific information about the presence of the trapped oil phase and the movement of the oil/water interface/meniscus in the network. The recovery curve is extracted based on the measured volume of oil at the outlet of the ROC. We also provide the first indication that this oil-recovery trend realized at chip-level can be correlated to the flooding experiments related to actual reservoir cores. Hence, we have successfully demonstrated that the conceptualized 'Reservoir-on-a-Chip' has the features of a realistic pore-network and in principle is able to perform the necessary flooding experiments that are routinely done in reservoir engineering.

  20. Advances and Applications of Rock Physics for Hydrocarbon Exploration

    Directory of Open Access Journals (Sweden)

    Valle-Molina C.

    2012-10-01

    Full Text Available Integration of the geological and geophysical information with different scale and features is the key point to establish relationships between petrophysical and elastic characteristics of the rocks in the reservoir. It is very important to present the fundamentals and current methodologies of the rock physics analyses applied to hydrocarbons exploration among engineers and Mexican students. This work represents an effort to capacitate personnel of oil exploration through the revision of the subjects of rock physics. The main aim is to show updated improvements and applications of rock physics into seismology for exploration. Most of the methodologies presented in this document are related to the study the physical and geological mechanisms that impact on the elastic properties of the rock reservoirs based on rock specimens characterization and geophysical borehole information. Predictions of the rock properties (litology, porosity, fluid in the voids can be performed using 3D seismic data that shall be properly calibrated with experimental measurements in rock cores and seismic well log data

  1. LBL/Industry fractured reservoir performance definition project

    Energy Technology Data Exchange (ETDEWEB)

    Benson, S.M. [Lawrence Berkeley Lab., CA (United States)

    1995-04-01

    One of the problems facing the petroleum industry is the recovery of oil from heterogeneous, fractured reservoirs and from reservoirs that have been partially depleted. In response to this need, several companies, notably British Petroleum USA, (BP) and Continental Oil Company (CONOCO), have established integrated reservoir description programs. Concurrently, LBL is actively involved in developing characterization technology for heterogeneous, fractured rock, mainly for DOE`s Civilian Nuclear Waste Program as well as Geothermal Energy programs. The technology developed for these programs was noticed by the petroleum industry and resulted in cooperative research centered on the petroleum companies test facilities. The emphasis of this work is a tightly integrated interdisciplinary approach to the problem of characterizing complex, heterogeneous earth materials. In this approach we explicitly combine the geologic, geomechanical, geophysical and hydrologic information in a unified model for predicting fluid flow. The overall objective is to derive improved integrated approaches to characterizing naturally fractured gas reservoirs.

  2. Reservoir simulation with MUFITS code: Extension for double porosity reservoirs and flows in horizontal wells

    Science.gov (United States)

    Afanasyev, Andrey

    2017-04-01

    Numerical modelling of multiphase flows in porous medium is necessary in many applications concerning subsurface utilization. An incomplete list of those applications includes oil and gas fields exploration, underground carbon dioxide storage and geothermal energy production. The numerical simulations are conducted using complicated computer programs called reservoir simulators. A robust simulator should include a wide range of modelling options covering various exploration techniques, rock and fluid properties, and geological settings. In this work we present a recent development of new options in MUFITS code [1]. The first option concerns modelling of multiphase flows in double-porosity double-permeability reservoirs. We describe internal representation of reservoir models in MUFITS, which are constructed as a 3D graph of grid blocks, pipe segments, interfaces, etc. In case of double porosity reservoir, two linked nodes of the graph correspond to a grid cell. We simulate the 6th SPE comparative problem [2] and a five-spot geothermal production problem to validate the option. The second option concerns modelling of flows in porous medium coupled with flows in horizontal wells that are represented in the 3D graph as a sequence of pipe segments linked with pipe junctions. The well completions link the pipe segments with reservoir. The hydraulics in the wellbore, i.e. the frictional pressure drop, is calculated in accordance with Haaland's formula. We validate the option against the 7th SPE comparative problem [3]. We acknowledge financial support by the Russian Foundation for Basic Research (project No RFBR-15-31-20585). References [1] Afanasyev, A. MUFITS Reservoir Simulation Software (www.mufits.imec.msu.ru). [2] Firoozabadi A. et al. Sixth SPE Comparative Solution Project: Dual-Porosity Simulators // J. Petrol. Tech. 1990. V.42. N.6. P.710-715. [3] Nghiem L., et al. Seventh SPE Comparative Solution Project: Modelling of Horizontal Wells in Reservoir Simulation

  3. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  4. Automated sliding susceptibility mapping of rock slopes

    Directory of Open Access Journals (Sweden)

    A. Günther

    2004-01-01

    Full Text Available We present a suite of extensions for ARCVIEW GIS™ (ESRI that allows to map the spatial distribution of first-order mechanical slope-properties in hard rock terrain, e.g. for large slope areas like water reservoir slopes. Besides digital elevation data, this expert-system includes regional continuous grid-based data on geological structures that might act as potential sliding or cutoff planes for rockslides. The system allows rapid automated mapping of geometrical and kinematical slope properties in hard rock, providing the basis for spatially distributed deterministic sliding-susceptibility evaluations on a pixel base. Changing hydrostatic slope conditions and rock mechanical parameters can be implemented and used for simple predictive static stability calculations. Application is demonstrated for a study area in the Harz Mts., Germany.

  5. A History of the Rock Island District Corps of Engineers, 1866-1975

    Science.gov (United States)

    1975-06-01

    on the upstream slope of the Red Rock Reservoir dam. FIG. 61 . Construction of the outlet works and spillway at Sayler - ville Reservoir. FIG. 62. An...Science degree in civil engineering. For two years after graduation he worked as a structural engineer for the American Bridge Company in Gary , Indiana

  6. Connectivity of channelized reservoirs: a modelling approach

    Energy Technology Data Exchange (ETDEWEB)

    Larue, David K. [ChevronTexaco, Bakersfield, CA (United States); Hovadik, Joseph [ChevronTexaco, San Ramon, CA (United States)

    2006-07-01

    ;two-dimensional', connectivity should follow the 2D 'S-curve'. For channelized reservoirs in map view, this occurs with straight, parallel channels. This 2D effect can also occur in layered reservoirs, where thin channelized sheets are separated vertically by sealing mudstone horizons. Evidence of transitional 2D to 3D behaviour is presented in this study. As the gross rock volume of a reservoir is reduced (for example, by fault compartmentalization) relative to the size of the depositional element (for example, the channel body), there are fewer potential connecting pathways. Lack of support volume creates additional uncertainty in connectivity and may substantially reduce connectivity. Connectivity can also be reduced by continuous mudstone drapes along the base of channel surfaces, by mudstone beds that are continuous within channel deposits, or muddy inclined heterolithic stratification. Finally, connectivity can be reduced by 'compensational' stacking of channel deposits, in which channels avoid amalgamating with other channel deposits. Other factors have been studied to address impact on connectivity, including modelling program type, presence of shale-filled channels and nested hierarchical modelling. Most of the stratigraphic factors that affect reservoir connectivity can be addressed by careful geological studies of available core, well log and seismic data. Remaining uncertainty can be addressed by constructing 3D geological models. (Author)

  7. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    With the advancement in oil exploration,producible oil and gas are being found in low resistivity reservoirs,which may otherwise be erroneously thought as water zones from their resistivity.However,the evaluation of low resistivity reservoirs remains difficult from log interpretation.Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay,laminated shale,conductive matrix grains,microscopic capillary pores and high saline water,a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations.Herein,a generalized effective medium resistivity model has been proposed for low resistivity reservoirs,based on experimental measurements on artificial low resistivity shaly sand samples,symmetrical anisotropic effective medium theory for resistivity interpretations,and geneses and conductance mechanisms of low resistivity reservoirs.By analyzing effects of some factors on the proposed model,we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses.Also,shale distribution largely affects water saturation predicted by the model.Resistivity index decreases as fraction and conductivity of laminated shale,or fraction of dispersed clay,or conductivity of rock matrix grains increases.Resistivity index decreases as matrix percolation exponent,or percolation rate of capillary bound water increases,and as percolation exponent of capillary bound water,or matrix percolation rate,or free water percolation rate decreases.Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water,dispersed clay,microscopic capillary pores,laminated shale and conductive matrix grains,and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  8. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    SONG YanJie; TANG XiaoMin

    2008-01-01

    With the advancement in oil exploration, producible oil and gas are being found in low resistivity reservoirs, which may otherwise be erroneously thought as water zones from their resistivity. However,the evaluation of low resistivity reservoirs remains difficult from log interpretation. Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay, laminated shale, conductive matrix grains, microscopic capillary pores and high saline water, a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations. Herein, a generalized effective medium resistivity model has been proposed for low resistivity reservoirs, based on experimental measurements on artificial low resistivity shaly sand samples, symmetrical anisotropic effective medium theory for resistivity interpretations, and geneses and conductance mechanisms of low resistivity reservoirs. By analyzing effects of some factors on the proposed model, we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses. Also,shale distribution largely affects water saturation predicted by the model. Resistivity index decreases as fraction and conductivity of laminated shale, or fraction of dispersed clay, or conductivity of rock matrix grains increases. Resistivity index decreases as matrix percolation exponent, or percolation rate of capillary bound water increases, and as percolation exponent of capillary bound water, or matrix percolation rate, or free water percolation rate decreases. Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water, dispersed clay, microscopic capillary pores, laminated shale and conductive matrix grains, and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  9. Energy R and D. Geothermal energy and underground reservoirs; R et D energie. Geothermie et reservoirs souterrains

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Geothermal energy appears as a viable economic alternative among the different renewable energy sources. The French bureau of geological and mining researches (BRGM) is involved in several research and development programs in the domain of geothermal energy and underground reservoirs. This document presents the content of 5 programs: the deep hot dry rock system of Soultz-sous-Forets (construction and testing of the scientific pilot, modeling of the reservoir structure), the development of low and high enthalpy geothermal energy in the French West Indies, the comparison of the geothermal development success of Bouillante (Guadeloupe, French West Indies) with the check of the geothermal development of Nyssiros (Greece) and Pantelleria (Italy), the development of the high enthalpy geothermal potentialities of Reunion Island, and the underground storage of CO{sub 2} emissions in geologic formations (deep aquifers, geothermal reservoirs, abandoned mines or oil reservoirs). (J.S.)

  10. Proposition d'explication de la formation d'hydrogène sulfuré dans les stockages souterrains de gaz naturel par réduction des sulfures minéraux de la roche magasin Proposed Explanation of Hydrogen-Sulfide Formation in Underground Natural-Gas Storage Structures by Reduction of Mineral Sulfides in the Reservoir Rock.

    Directory of Open Access Journals (Sweden)

    Bourgeois J. P.

    2006-11-01

    Full Text Available La formation d'hydrogène sulfuré dans les structures de stockage peu expliquer autrement que par l'action de bactéries sulfato-réductrices. La contenue dans la roche magasin constitue une source de sulfures capable d'alimenter en H2S le gaz naturel. La réduction de la pyrite en sulfures du type Fe 1-x S et l'équilibre de dissolution précipitation, lié principalement à la pression de CO2, dans les structures stockages, constituent un processus de formation d'H2S capable d'expliquer tativement et quantitativement les phénomènes observés sur le terrain. Un modèle simplifié de stockage reprend ce schéma et teste la sensibililté de la teneur en H2S à la valeur des paramètres physiques et chimiques définissant le stockage. Cette étude permet de proposer un certain nombre d'actions susceptibles de limiter la formation d'H2S et d'orienter les choix futurs du couple gaz naturel - structures de stockage. The formation of hydrogen sulfide in storage structures can be explained otherwise thon by the action of sulfate-reducing bacteria. The pyrite contained in the reservoir rock makes up a source of sulfides capable of supplying the natural gas with H2S.Reduction of pyrite ta sulfides of the Fe,-,S type and the dissolution precipitation equilibrium, linked mainly ta C02 pressure in storage structures, make up an H2S for-mation process capable of qualitatively and quantitatively explained phenomena observed in the field.A simplified storage model reflects this scheme and can be used ta test the sensi-tivity of the H2S content ta the value of the physical and chemical parameters defining the storage structure.This investigation can be used to propose various means of action (sable ta "mit H2S formation and ta guide future choices of natural gas/storage-structure pairs.

  11. Reservoir pressure evolution model during exploration drilling

    Directory of Open Access Journals (Sweden)

    Korotaev B. A.

    2017-03-01

    Full Text Available Based on the analysis of laboratory studies and literature data the method for estimating reservoir pressure in exploratory drilling has been proposed, it allows identify zones of abnormal reservoir pressure in the presence of seismic data on reservoir location depths. This method of assessment is based on developed at the end of the XX century methods using d- and σ-exponentials taking into account the mechanical drilling speed, rotor speed, bit load and its diameter, lithological constant and degree of rocks' compaction, mud density and "regional density". It is known that in exploratory drilling pulsation of pressure at the wellhead is observed. Such pulsation is a consequence of transferring reservoir pressure through clay. In the paper the mechanism for transferring pressure to the bottomhole as well as the behaviour of the clay layer during transmission of excess pressure has been described. A laboratory installation has been built, it has been used for modelling pressure propagation to the bottomhole of the well through a layer of clay. The bulge of the clay layer is established for 215.9 mm bottomhole diameter. Functional correlation of pressure propagation through the layer of clay has been determined and a reaction of the top clay layer has been shown to have bulge with a height of 25 mm. A pressure distribution scheme (balance has been developed, which takes into account the distance from layers with abnormal pressure to the bottomhole. A balance equation for reservoir pressure evaluation has been derived including well depth, distance from bottomhole to the top of the formation with abnormal pressure and density of clay.

  12. Multiple-Element Matching Reservoir Formation and Quantitative Prediction of Favorable Areas in Superimposed Basins

    Institute of Scientific and Technical Information of China (English)

    WANG Huaijie; PANG Xiongqi; WANG Zhaoming; YU Qiuhua; HUO Zhipeng; MENG Qingyang

    2010-01-01

    Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation,and complex hydrocarbon reservoirs have been discovered widely in basins of this kind.Most of the complex hydrocarbon reservoirs are characterized by relocation,scale re-construction,component variation and phase state transformation,and their distributions are very difficult to predict.Research shows that regional caprock(C),high-quality sedimentary facies(Deposits,D),paleohighs(Mountain,M)and source rock(S)are four geologic elements contributing to complex hydrocarbon reservoir formation and distribution of western superimposed basins.Longitudinal sequential combinations of the four elements control the strata of hydrocarbon reservoir formation,and planar superimpositions and combinations control the range of hydrocarbon reservoir and their simultaneous joint effects in geohistory determine the time of hydrocarbon reservoir formation.Multiple-element matching reservoir formation presents a basic mode of reservoir formation in superimposed basins,and we recommend it is expressed as T-CDMS.Based on the multiple-element matching reservoir formation mode,a comprehensive reservoir formation index(Tcdms)is developed in this paper to characterize reservoir formation conditions,and a method is presented to predict reservoir formation range and probability of occurrence in superimposed basins.Through application of new theory,methods and technology,the favorable reservoir formation range and probability of occurrence in the Ordovician target zone in Tarim Basin in four different reservoir formation periods are predicted.Results show that central Tarim,Yinmaili and Lunnan are the three most favorable regions where Ordovician oil and gas fields may have formed.The coincidence of prediction results with currently discovered hydrocarbon reservoirs reaches 97%.This reflects the effectiveness and reliability of the new theory,methods and technology.

  13. Diagenesis and Restructuring Mechanism of Oil and Gas Reservoir in the Marine Carbonate Formation, Northeastern Sichuan: A Case Study of the Puguang Gas Reservoir

    Institute of Scientific and Technical Information of China (English)

    DU Chunguo; WANG Jianjun; ZOU Huayao; ZHU Yangming; WANG Cunwu

    2009-01-01

    Based on the technology of balanced cross-section and physical simulation experiments associated with natural gas geochemical characteristic analyses, core and thin section observations, it has been proven that the Puguang gas reservoir has experienced two periods of diagenesis and restructuring since the Late lndo-Chinese epoch. One is the fluid transfer controlled by the tectonic movement and the other is geochemical reconstruction controlled by thermochemical sulfate reduction (TSR). The middle Yanshan epoch was the main period that the Puguang gas reservoir experienced the geochemical reaction of TSR. TSR can recreate the fluid in the gas reservoir, which makes the gas drying index higher and carbon isotope heavier because C_(2+) (ethane and heavy hydrocarbon) and ~(12)C (carbon 12 isotope) is first consumed relative to CH_4 and ~(13)C (carbon 13 isotope). However, the reciprocity between fluid regarding TSR (hydrocarbon, sulfureted hydrogen (H_2S), and water) and reservoir rock results in reservoir rock erosion and anhydrite alteration, which increases porosity in reservoir, thereby improving the petrophysical properties. Superimposed by later tectonic movement, the fluid in Puguang reservoir has twice experienced adjustment, one in the late Yanshan epoch to the early Himalayan epoch and the other time in late Himalayan epoch, after which Puguang gas reservoir is finally developed.

  14. Economic Impacts from Spending by Community Dock Owners at Table Rock Lake

    Science.gov (United States)

    2008-01-01

    Rock Lake, community dock • Rough River Lake, community dock • Pomme de Terre Lake, community dock • Harry S. Truman Dam and Reservoir, marina...owners at Table Rock Lake (Missouri/Arkansas), Rough River Lake (Kentucky), and Pomme de Terre Lake (Missouri). The ERB staff designed the survey

  15. Geotechnical Descriptions of Rock and Rock Masses.

    Science.gov (United States)

    1985-04-01

    weathering is presented by Dornbusch (1982). 39. Mechanical, or physical, weathering of rock occurs primarily by (a) freeze expansion (or frost wedging...34Engineering Classifica- tion of In-Situ Rock," Technical Report No. AFWL-TR-67-144, Air Force Weapons Laboratory, Kirtland Air Force Base, N. Mex. Dornbusch , W

  16. On the feasibility of inducing oil mobilization in existing reservoirs via wellbore harmonic fluid action

    KAUST Repository

    Jeong, Chanseok

    2011-03-01

    Although vibration-based mobilization of oil remaining in mature reservoirs is a promising low-cost method of enhanced oil recovery (EOR), research on its applicability at the reservoir scale is still at an early stage. In this paper, we use simplified models to study the potential for oil mobilization in homogeneous and fractured reservoirs, when harmonically oscillating fluids are injected/produced within a well. To this end, we investigate first whether waves, induced by fluid pressure oscillations at the well site, and propagating radially and away from the source in a homogeneous reservoir, could lead to oil droplet mobilization in the reservoir pore-space. We discuss both the fluid pore-pressure wave and the matrix elastic wave cases, as potential agents for increasing oil mobility. We then discuss the more realistic case of a fractured reservoir, where we study the fluid pore-pressure wave motion, while taking into account the leakage effect on the fracture wall. Numerical results show that, in homogeneous reservoirs, the rock-stress wave is a better energy-delivery agent than the fluid pore-pressure wave. However, neither the rock-stress wave nor the pore-pressure wave is likely to result in any significant residual oil mobilization at the reservoir scale. On the other hand, enhanced oil production from the fractured reservoir\\'s matrix zone, induced by cross-flow vibrations, appears to be feasible. In the fractured reservoir, the fluid pore-pressure wave is only weakly attenuated through the fractures, and thus could induce fluid exchange between the rock formation and the fracture space. The vibration-induced cross-flow is likely to improve the imbibition of water into the matrix zone and the expulsion of oil from it. © 2011 Elsevier B.V.

  17. Formation mechanism and model for sand lens reservoirs in the Jiyang Sub-basin, East China

    Institute of Scientific and Technical Information of China (English)

    LI; Pilong; PANG; Xiongqi; CHEN; Dongxia; ZHANG; Shanwen

    2004-01-01

    The Bohai Bay basin comprises some very important and well documented subtle traps known in China, which have been the major exploration focus and have become a major petroleum play since the 1990s. However, recent exploration showed that the oil-bearing properties of some sand lens reservoirs may vary significantly and the accumulation mechanisms for these lithological subtle traps are not well understood. Based on statistical analysis of oil-bearing properties for 123 sand lens reservoirs in the Jiyang Sub-basin and combined with detailed anatomy of typical sand lens reservoirs and NMR experiments, it has been shown that the structural and sedimentary factors, hydrocarbon generation and expulsion conditions of the surrounding source rocks, as well as the petrophysical properties of sand lens reservoirs are the main controlling factors for the formation of sand lens reservoirs. The formation of a sand lens reservoir depends on the interaction between the hydrocarbon accumulation driving force and the resistance force. The driving force is made up of the differential capillary pressure between sandstones and sources rocks and the hydrocarbon diffusion force, and as well as the hydrocarbon expansion force. The resistance force is the friction resistance force for hydrocarbons and water to move through the pore throats of the sand lens. The sedimentary environment, source rock condition and sand reservoir properties can change from unfavorable to favorable depending on the combination of these factors. When these three factors all reach certain thresholds, the sand lens reservoirs may begin to be filled by hydrocarbons. When all of these conditions become favorable for the formation of sand lens reservoirs, the reservoir would have high oil saturation. This approach has been applied to evaluating the potential of petroleum accumulation in the sand lens reservoirs in the third member of the Neogene Shahejie Formation in the Jiyang Sub-basin.

  18. New geomechanical developments for reservoir management; Desenvolvimentos experimentais e computacionais para analises geomecanicas de reservatorio

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Antonio C.; Menezes Filho, Armando Prestes; Silvestre, Jose R. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    The common assumption that oil is produced under a constant rate only considering reservoir depletion has been questioned for some time. An usual hypothesis is that the physical properties of a reservoir are not constants during time, but they vary according to the properties of reservoir rock and the characteristics of the external loads. More precisely, as soon as a reservoir is explored, the volume of fluid diminishes, decreasing the static pressure and increasing the effective stress over the rock skeleton, which, depending on the nature of rock, can lead to a gradual deformation and alteration of reservoir's porosity and permeability, and oil productivity as well. This paper aims at showing numerical and experimental achievements, developed by the Well bore Engineering Technology Department of CENPES, devoted to the characterization of the influence of stress-strain states on the permeability and production of reservoir rocks. It is believed that these developments can possibly bring some light to the understanding of this complex phenomenon, besides allowing the establishment of more realistic relations involving stress-strain-permeability in coupled fluid dynamic problems. (author)

  19. Main controlling factors for hydrocarbon reservoir formation and petroleum distribution in Cratonic Area of Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Cratonic Area of the Tarim Basin is located in the central part of the basin, developing primarily with Cambrian marine source rocks and secondly Middle to Upper Ordovician marine and Carboniferous-Permian transitional facies source rocks. The source rocks were matured in the changeable period and space, forming multiple hydrocarbon generating centers during the periods. The Cratonic Area experienced multiple tectonic orogenies, forming several palaeouplifts. The matching condition between effective hydrocarbon generating centers and the palaeouplifts in various periods is the main control factor for the formation and distribution of hydrocarbon reservoirs. The palaeouplifts have experienced multiple hydrocarbon-filling phases, several periods of modifications and even breakdown. The palaeouplifts and the adjacent slopes around the effective hydrocarbon generating center compose the most favorable places for hydrocarbon accumulation. The hydrocarbon phase is related with the evolution of the hydrocarbon generating center. In the Tarim Basin's Cratonic Area, reservoirs were mostly formed during late Hercynian. The originally formed hydrocarbon reservoirs which are adjacent to source kitchens and in the good preservation condition are the most favorable prospecting targets. Hydrocarbon is richly accumulated under the regional caprock, surrounding the faulted trends, and over and below the unconformity surfaces. Reservoirs in the Carboniferous sandstone, Ordovician karstic weathered crust and carbonate rock inside the buried hill compose the main intervals for hydrocarbon accumulation. Carboniferous and Silurian sandstone pinchout reservoirs and carbonate lithologic reservoirs with rich fractures and pores are the main targets for further prospecting.

  20. The Rock Cycle

    Science.gov (United States)

    Singh, Raman J.; Bushee, Jonathan

    1977-01-01

    Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

  1. Pyritization effect on well logging parameters in Jurassic reservoirs within S-E Western Siberian oil fields

    Science.gov (United States)

    Janishevskii, A.; Ten, T.; Ezhova, A.

    2016-09-01

    Authigenic sulfide mineralization in hydrocarbon-saturated reservoirs distorts the electrical and density properties of rocks. The correlation between volumetric density, electro-conductive minerals and open porosity in 300 samples were determined. This fact made it possible to develop a nomograph in evaluating oil saturated reservoirs and could be applied in well geophysical survey data interpretation.

  2. Geological characterization of deep reservoir and barrier horizons in Germany. Storage Catalogue of Germany; Geologische Charakterisierung tiefliegender Speicher- und Barrierehorizonte in Deutschland. Speicher-Kataster Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Christian [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Berlin (Germany); Reinhold, Klaus (eds.) [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany)

    2011-07-01

    Within the series of publication under consideration of the German Society for Geosciences e.V. (Hanover, Federal Republic of Germany) the following contributions are presented: (1) Storage potential of the deeper subsurface - Overview and results from the project Storage Catalogue of Germany (K. Reinhold); (2) Information system on geological reservoir and barrier rock units (Storage Catalogue of Germany) (C. Riesenberg); (3) Distribution and properties of Mesozoic sandstones and barrier rocks in Schleswig-Holstein and Hamburg- Basic information on possible energetic utilisation of the deeper subsurface (H. Kaufhold); (4) Geological characterization of potential reservoir and barrier rock units in Mecklenburg - Western Pomerania (J. Brandes); (5)Reservoir and barrier rocks in the deep underground of Brandenburg and Berlin (A. Bebiolka); (6) Deep aquifers in Saxony-Anhalt and their potential for the underground storage (K. Reinhold); (7) Distribution and characterization of deep reservoir and barrier horizons in Lower Saxony and Bremen (S. Knopf); (8) Geological characterization of reservoir and barrier rocks in North Rhine-Westphalia (M. Doelling); (9) CO{sub 2} storage potential in deep saline aquifers in the state of Hesse, Germany (A. Koett); (10) Geological characterization of reservoir and barrier rocks in the deeper subsurface of the Free State of Thuringia (Germany) (H. Huckriede); (11) Storage potential in the deeper subsurface of Saarland and Rhineland-Palatina (J. Haneke); (12) Storage potential in the deeper subsurface of Saarland and Baden-Wuerttemberg (C. Fehn); (13) Deep reservoir and barrier rock units in Bavaria - an overview (G.W. Diepolder).

  3. Fractures and Rock Mechanics, Phase 1

    DEFF Research Database (Denmark)

    Havmøller, Ole; Krogsbøll, Anette

    1997-01-01

    The main objectives of the project are to combine geological description of fractures, chalk types and rock mechanical properties, and to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. Five chalk types, representing two outcrop localities: Stevns and Hillers......The main objectives of the project are to combine geological description of fractures, chalk types and rock mechanical properties, and to investigate whether the chosen outcrops can be used as analogues to reservoir chalks. Five chalk types, representing two outcrop localities: Stevns...... and Hillerslev, and three reservoir zones: Tyra Maastrictian, Valhall Tor and Valhall Hod are investigated. Different test types are applied in small and large scale in order to investigate the influence on stiffness and strength from natural and induced fractures, stylolites, bedding planes and healed fractures....... The main conclusions are: that Hillerslev and Stevns can be regarded as close analogues to the Valhall Tor formation, but neither to Valhall Hod nor to Tyra formations; and that compressive strength is reduced by initial fractures, whereas stifness seems to be unaffected; and that large test specimens have...

  4. Étude de la mouillabilité des roches réservoir à l'échelle du pore par cryomicroscopie électronique à balayage Wettability of Reservoir Rock At the Pore Scale: Contribution of Cryo-Scanning Electron Microscopy

    Directory of Open Access Journals (Sweden)

    Fassi-Fihri O.

    2006-11-01

    éralogie qui est plutôt homogène. Wettability is generally considered to be one of the principal parameters influencing the distribution, saturation and flow of fluids in porous media. Reservoir rock wettability has long been approached by overall or indirect methods [1] (capillary pressure or relative permeability curves, contact angle, fluid displacement, etc. . Few studies until now have led to a detailed description of porous media with intermediate wettability. - Is there any evidence of an intermediate behavior of fluids in contact with minerals distributed homogeneously throughout the medium, or is there a heterogeneous distribution of water- and oil-wettabilities within the porous medium?- What influence does the local heterogeneity of the minerals (size, geometry, surface chemistry, etc. have on fluid distribution [2 to 7]?The answer to these questions requires a microscopic-scale description of saturated porous media [8 to 11]. By using the imaging and analytical capabilities of a scanning electron microscope coupled with a cold stage unit, fluids can be visualized and identified by detection of their natural tracer element (sulfur for oil and chlorine for brine, and their relative distribution within the pore space can be analyzed in terms of wettability. Results presented here illustrate both the interest of the method and its applicability to actual reservoir rocks. Small cores of the chosen porous media were first saturated with brine, flooded to irreducible water saturation by centrifuging in oil, aged in oil for one month and finally flooded to residual oil saturation by centrifuging in brine. Samples were then frozen in nitrogen slush, freeze fractured and coated before being transferred to the cold stage of the microscope for observation. Experiments were first conducted on porous media with controlled wettability : model sintered glass media, natural clean sandstone (Fontainebleau and clayey sandstones (Vosges, Velaines. All these porous media are

  5. Advanced Reservoir Characterization and Evaluation of C02 Gravity Drainage in the Naturally Fractured Sprayberry Trend Area

    Energy Technology Data Exchange (ETDEWEB)

    David S. Schechter

    1998-04-30

    The objective is to assess the economic feasibility of CO2 flooding of the naturally fractured Straberry Trend Area in west Texas. Research is being conducted in the extensive characterization of the reservoirs, the experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, the analytical and numerical simulation of Spraberry reservoirs, and the experimental investigations on CO2 gravity drainage in Spraberry whole cores.

  6. Gypsy Field Project in Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    John P. Castagna; William J. Lamb; Carlos Moreno; Roger Young; Lynn Soreghan

    2000-09-19

    The objective of the Gypsy Project was to properly calculate seismic attributes and integrate these into a reservoir characterization project. Significant progress was made on the project in four areas. (1) Attenuation: In order for seismic inversion for rock properties or calculation of seismic attributes used to estimate rock properties to be performed validly, it is necessary to deal with seismic data that has had true amplitude and frequency content restored to account for earth filtering effects that are generally not included in seismic reservoir characterization methodologies. This requires the accurate measurement of seismic attenuation, something that is rarely achieved in practice. It is hoped that such measurements may also provide additional independent seismic attributes for use in reservoir characterization studies. In 2000, we were concerned with the ground truthing of attenuation measurements in the vicinity of wells. Our approach to the problem is one of extracting as time varying wavelet and relating temporal variations in the wavelet to an attenuation model of the earth. This method has the advantage of correcting for temporal variations in the reflectivity spectrum of the earth which confound the spectral ratio methodology which is the most commonly applied means of measuring attenuation from surface seismic data. Part I of the report describes our efforts in seismic attenuation as applied to the Gypsy data. (2) Optimal Attributes: A bewildering array of seismic attributes is available to the reservoir geoscientist to try to establish correlations to rock properties. Ultimately, the use of such a large number of degrees of freedom in the search for correlations with limited well control leads to common misapplication of statistically insignificant results which yields invalid predictions. Cross-validation against unused wells can be used to recognize such problems, but does not offer a solution to the question of which attributes should be used

  7. Quantitative seismic interpretation: Applying rock physics tools to reduce interpretation risk

    Institute of Scientific and Technical Information of China (English)

    Yong Chen

    2007-01-01

    @@ Seismic data analysis is one of the key technologies for characterizing reservoirs and monitoring subsurface pore fluids. While there have been great advances in 3D seismic data processing, the quantitative interpretation of the seismic data for rock properties still poses many challenges. This book demonstrates how rock physics can be applied to predict reservoir parameters, such as lithologies and pore fluids, from seismically derived attributes, as well as how the multidisciplinary combination of rock physics models with seismic data, sedimentological information, and stochastic techniques can lead to more powerful results than can be obtained from a single technique.

  8. A computer-assisted rock type data catalogue for gas formations; Ein rechnergestuetzter Gesteinsdatenkatalog fuer Gasformationen

    Energy Technology Data Exchange (ETDEWEB)

    Reitenbach, V.; Pusch, G.; Moeller, M.; Koll, S. [TU Clausthal (Germany). Inst. fuer Erdoel- und Erdgastechnik; Constantini, A.; Junker, A.; Anton, H. [RWE Dea AG, Hamburg (Germany)

    2007-09-13

    Modern reservoir management commonly requires versatile reservoir data which are neces-sary for integrated reservoir characterization, evaluation and development planning. The rock data necessary for numerical reservoir simulation studies often have to be collected from different sources, analysed and sorted with a considerable effort. In a framework of DGMK research program (DGMK project 593-9/4), the Institute of Petro-leum Engineering (Clausthal University of Technology) and RWE DEA AG have developed a new tool named Rock Data Catalogue, which is capable of managing large amounts of rock data more efficiently and deriving new specific correlations for European rock types. The use of Rock Data Catalogue can facilitate the essential input data generation and proc-essing procedure for reservoir simulation studies. The Rock Data Catalogue is comprised of a Data Base Module of digitalized reservoir rock data and an interactive Data Correlation Module. Both modules are built-up as an interface to common reservoir simulation software. The universal structure of the software also makes it possible to exchange the data with other rock data information systems. The Data Correlation Module implements a ''Decision-Structure'' module, which helps the reservoir engineer to select the rock data for analysis and correlation depending on its litho-facial type and permeability class. The Data Base Module enables a quick search of appro-priated data sets and their export into the correlation module. The open source data of the North German Rotliegend gas formations as well as the data of measurements on Rotliegend core samples performed at the ITE in course of the DGMK tight gas projects were implemented in the rock data base. Correlations of poro/perm data, two-phase flow and capillary pressure functions of the Rotliegend sandstones with the per-meability range between 20 and 0.01 mD are implemented in the rock data base and serve for quality checking of the

  9. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer

    2008-09-15

    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  10. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  11. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  12. Session: Reservoir Technology

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N.; Shook, G. Michael

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook

  13. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister

    2011-01-01

    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  14. Geomechanical Properties of Unconventional Shale Reservoirs

    Directory of Open Access Journals (Sweden)

    Mohammad O. Eshkalak

    2014-01-01

    Full Text Available Production from unconventional reservoirs has gained an increased attention among operators in North America during past years and is believed to secure the energy demand for next decades. Economic production from unconventional reservoirs is mainly attributed to realizing the complexities and key fundamentals of reservoir formation properties. Geomechanical well logs (including well logs such as total minimum horizontal stress, Poisson’s ratio, and Young, shear, and bulk modulus are secured source to obtain these substantial shale rock properties. However, running these geomechanical well logs for the entire asset is not a common practice that is associated with the cost of obtaining these well logs. In this study, synthetic geomechanical well logs for a Marcellus shale asset located in southern Pennsylvania are generated using data-driven modeling. Full-field geomechanical distributions (map and volumes of this asset for five geomechanical properties are also created using general geostatistical methods coupled with data-driven modeling. The results showed that synthetic geomechanical well logs and real field logs fall into each other when the input dataset has not seen the real field well logs. Geomechanical distributions of the Marcellus shale improved significantly when full-field data is incorporated in the geostatistical calculations.

  15. Rock mechanics related to Jurassic underburden at Valdemar oil field

    DEFF Research Database (Denmark)

    Foged, Niels

    1999-01-01

    .It has been initiated as a feasibility study of the North Jens-1 core 12 taken in the top Jurassic clay shale as a test specimens for integrated petrological, mineralogical and rock mechanical studies. Following topics are studied:(1) Pore pressure generation due to conversion of organic matter...... and deformation properties of the clay shale using the actual core material or outcrop equivalents.(3) Flushing mechanisms for oil and gas from source rocks due to possibly very high pore water pressure creating unstable conditions in deeply burried sedimentsThere seems to be a need for integrating the knowledge...... in a number of geosciences to the benefit of common understanding of important reservoir mechanisms. Rock mechanics and geotechnical modelling might be key points for this understanding of reservoir geology and these may constitute a platform for future research in the maturing and migration from the Jurassic...

  16. Hot Dry Rock Geothermal Energy Development Program

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.

    1989-12-01

    During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.

  17. Hot Dry Rock; Geothermal Energy

    Energy Technology Data Exchange (ETDEWEB)

    None

    1990-01-01

    The commercial utilization of geothermal energy forms the basis of the largest renewable energy industry in the world. More than 5000 Mw of electrical power are currently in production from approximately 210 plants and 10 000 Mw thermal are used in direct use processes. The majority of these systems are located in the well defined geothermal generally associated with crustal plate boundaries or hot spots. The essential requirements of high subsurface temperature with huge volumes of exploitable fluids, coupled to environmental and market factors, limit the choice of suitable sites significantly. The Hot Dry Rock (HDR) concept at any depth originally offered a dream of unlimited expansion for the geothermal industry by relaxing the location constraints by drilling deep enough to reach adequate temperatures. Now, after 20 years intensive work by international teams and expenditures of more than $250 million, it is vital to review the position of HDR in relation to the established geothermal industry. The HDR resource is merely a body of rock at elevated temperatures with insufficient fluids in place to enable the heat to be extracted without the need for injection wells. All of the major field experiments in HDR have shown that the natural fracture systems form the heat transfer surfaces and that it is these fractures that must be for geothermal systems producing from naturally fractured formations provide a basis for directing the forthcoming but, equally, they require accepting significant location constraints on HDR for the time being. This paper presents a model HDR system designed for commercial operations in the UK and uses production data from hydrothermal systems in Japan and the USA to demonstrate the reservoir performance requirements for viable operations. It is shown that these characteristics are not likely to be achieved in host rocks without stimulation processes. However, the long term goal of artificial geothermal systems developed by systematic

  18. Rock History and Culture

    OpenAIRE

    Gonzalez, Éric

    2013-01-01

    Two ambitious works written by French-speaking scholars tackle rock music as a research object, from different but complementary perspectives. Both are a definite must-read for anyone interested in the contextualisation of rock music in western popular culture. In Une histoire musicale du rock (i.e. A Musical History of Rock), rock music is approached from the point of view of the people – musicians and industry – behind the music. Christophe Pirenne endeavours to examine that field from a m...

  19. Reservoir souring: it is all about risk mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Kuijvenhoven, Cor [Shell (Canada)

    2011-07-01

    The presence of H2S in produced fluid can be due to various sources, among which are heat/rock interaction and leaks from other reservoirs. This paper discusses the reasons, risk assessment and tools for mitigating reservoir souring. Uncontrolled microorganism activity can cause a sweet reservoir (without H2S) to become sour (production of H2S). The development of bacteria is one of the main causes of reservoir souring in unconventional gas fields. It is difficult to predict souring in seawater due to produced water re-injection (PWRI). Risk assessment and modeling techniques for reservoir souring are discussed. Some of the factors controlling H2S production include injection location, presence of scavenging minerals and biogenic souring. Mitigation methods such as biocide treatment of injection water, sulphate removal from seawater, microbial monitoring techniques such as the molecular microbiology method (MMM), and enumeration by serial dilution are explained. In summary, it can be concluded that reservoir souring is a long-term problem and should be assessed at the beginning of operations.

  20. An upscaling procedure for fractured reservoirs with embedded grids

    Science.gov (United States)

    Fumagalli, Alessio; Pasquale, Luca; Zonca, Stefano; Micheletti, Stefano

    2016-08-01

    Upscaling of geological models for reservoir simulation is an active and important area of research. In particular, we are interested in reservoirs where the rock matrix exhibits an intricate network of fractures, which usually acts as a preferential path to the flow. Accounting for fractures' contribution in the simulation of a reservoir is of paramount importance. Here we have focused on obtaining effective parameters (e.g., transmissibility) on a 3-D computational grid on the reservoir scale, which account for the presence, at a finer spatial scale, of fractures and a network of fractures. We have essentially followed the idea illustrated in Karimi-Fard et al. (2006), yet this work has some notable aspects of innovation in the way the procedure has been implemented, and in its capability to consider rather general corner-point grids, like the ones normally used in reservoir simulations in the industry, and complex and realistic fracture networks, possibly not fully connected inside the coarse cells. In particular, novel contribution is the employment of an Embedded Discrete Fracture Model (EDFM) for computing fracture-fracture and matrix-fracture transmissibilities, with a remarkable gain in speedup. The output is in the form of transmissibility that, although obtained by considering single-phase flow, can be used for coarse-scale multiphase reservoir simulations, also via industrial software, such as Eclipse, Intersect, or GPRS. The results demonstrate the effectiveness and computational efficiency of the numerical procedure which is now ready for further testing and industrialization.

  1. SILTATION IN RESERVOIRS

    African Journals Online (AJOL)

    human resources. It is also intended to make known to the general public that ... port processes were not properly taken into account. ... Studies carried out on 19 reservoirs in Cen- tral Europe with storage capacity ranging be- tween 1.48 x ...

  2. Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity in reservoir models. First annual report, September 29, 1993--September 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Martin, F.D.; Buckley, J.S.; Weiss, W.W.; Ouenes, A.

    1995-05-01

    The goal of this project is to provide a more quantitative definition of reservoir heterogeneity. This objective will be accomplished through the integration of geologic, geophysical, and engineering databases into a multidisciplinary understanding of reservoir architecture and associated fluid-rock and fluid-fluid interactions. The intent is to obtain a quantitative reservoir description incorporating outcrop, field, well-to-well, and laboratory core and fluid data of widely varying scales. This interdisciplinary effort will integrate geological and geophysical data with engineering and petrophysical results through reservoir simulation to quantify reservoir architecture and the dynamics of fluid-rock and fluid-fluid interactions. A more accurate reservoir description will allow greater accuracy and confidence during simulation and modeling as steps toward gaining greater recovery efficiency from existing reservoirs. A field laboratory, the Sulimar Queen Unit, is available for the field research activities that will be conducted.

  3. Geologic map of the Morena Reservoir 7.5-minute quadrangle, San Diego County, California

    Science.gov (United States)

    Todd, Victoria R.

    2016-06-01

    IntroductionMapping in the Morena Reservoir 7.5-minute quadrangle began in 1980, when the Hauser Wilderness Area, which straddles the Morena Reservoir and Barrett Lake quadrangles, was mapped for the U.S. Forest Service. Mapping was completed in 1993–1994. The Morena Reservoir quadrangle contains part of a regional-scale Late Jurassic(?) to Early Cretaceous tectonic suture that coincides with the western limit of Jurassic metagranites in this part of the Peninsular Ranges batholith (PRB). This suture, and a nearly coincident map unit consisting of metamorphosed Cretaceous and Jurassic back-arc basinal volcanic and sedimentary rocks (unit KJvs), mark the boundary between western, predominantly metavolcanic rocks, and eastern, mainly metasedimentary, rocks. The suture is intruded and truncated by the western margin of middle to Late Cretaceous Granite Mountain and La Posta plutons of the eastern zone of the batholith.

  4. A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad Ghassemi

    2003-06-30

    Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are

  5. Reservoir geochemistry: A link between reservoir geology and engineering?

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S.R.; Aplin, A.C. [Univ. of Newcastle upon Tyne (United Kingdom); Corbett, P.; Ementon, N. [Heriot-Watt Univ., Edinburgh (United Kingdom)

    1994-12-31

    Geochemistry provides a natural but poorly exploited link between reservoir geology and engineering. The authors summarize some current applications of geochemistry to reservoir description and stress that because of their strong interactions with mineral surfaces and water, nitrogen and oxygen compounds in petroleum may exert an important influence on the PVT properties of petroleum, viscosity and wettability. The distribution of these compounds in reservoirs is heterogeneous on a sub-meter scale and is partly controlled by variations in reservoir quality. The implied variations in petroleum properties and wettability may account for some of the errors in reservoir simulations.

  6. Reservoir geochemistry: A link between reservoir geology and engineering?

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S.R.; Aplin, A.C.; Chen, M.; Taylor, P.N. [Univ. of Newcastle (Australia); Corbett, P.W.M.; Ementon, N. [Heriot-Watt Univ., Edinburgh (United Kingdom)

    1997-02-01

    Geochemistry provides a natural, but poorly exploited, link between reservoir geology and engineering. The authors summarize some current applications of geochemistry to reservoir description and stress that, because of their strong interactions with mineral surfaces and water, nitrogen and oxygen compounds in petroleum may exert an important influence on the pressure/volume/temperature (PVT) properties of petroleum, viscosity and wettability. The distribution of these compounds in reservoirs is heterogeneous on a submeter scale and is partly controlled by variations in reservoir quality. The implied variations in petroleum properties and wettability may account for some of the errors in reservoir simulations.

  7. Environmental Characteristics of Reservoir Systems in the Czech Republic

    Science.gov (United States)

    2003-07-01

    highest parts, at the watershed border, there are also granitic rocks (mostly Cadomian). The geological age is Lower Paleozoic – Proterozoic . Fifteen...are included. Stratification of temperature, dissolved oxygen , pH, and alkalinity has been measured at the dam station (St. 16) in three-week...because of relatively imprecise measurement of water surface level of the reservoir pool. Stratification of temperature, dissolved oxygen , pH, and

  8. Determination of petrophysical properties of sedimentary rocks by optical methods

    Science.gov (United States)

    Korte, D.; Kaukler, D.; Fanetti, M.; Cabrera, H.; Daubront, E.; Franko, M.

    2017-04-01

    Petrophysical properties of rocks (thermal diffusivity and conductivity, porosity and density) as well as the correlation between them are of great importance for many geoscientific applications. The porosity of the reservoir rocks and their permeability are the most fundamental physical properties with respect to the storage and transmission of fluids, mainly oil characterization. Accurate knowledge of these parameters for any hydrocarbon reservoir is required for efficient development, management, and prediction of future performance of the oilfield. Thus, the porosity and permeability, as well as the chemical composition must be quantified as precisely as possible. This should be done along with the thermal properties, density, conductivity, diffusivity and effusivity that are intimately related with them. For this reason, photothermal Beam Deflection Spectrometry (BDS) technique for determination of materials' thermal properties together with other methods such as Energy Dispersive X-ray Scanning Electron Microscopy (SEM-EDX) for determining the chemical composition and sample structure, as well as optical microscopy to determine the particles size, were applied for characterization of sedimentary rocks. The rocks were obtained from the Andes south flank in the Venezuela's western basin. The validation of BDS applicability for determination of petrophysical properties of three sedimentary rocks of different texture and composition (all from Late Cretaceous associated with the Luna, Capacho and Colón-Mito Juan geological formations) was performed. The rocks' thermal properties were correlated to the microstructures and chemical composition of the examined samples.

  9. Geochemical and tectonic uplift controls on rock nitrogen inputs across terrestrial ecosystems

    Science.gov (United States)

    Morford, Scott L.; Houlton, Benjamin Z.; Dahlgren, Randy A.

    2016-02-01

    Rock contains > 99% of Earth's reactive nitrogen (N), but questions remain over the direct importance of rock N weathering inputs to terrestrial biogeochemical cycling. Here we investigate the factors that regulate rock N abundance and develop a new model for quantifying rock N mobilization fluxes across desert to temperate rainforest ecosystems in California, USA. We analyzed the N content of 968 rock samples from 531 locations and compiled 178 cosmogenically derived denudation estimates from across the region to identify landscapes and ecosystems where rocks account for a significant fraction of terrestrial N inputs. Strong coherence between rock N content and geophysical factors, such as protolith, (i.e. parent rock), grain size, and thermal history, are observed. A spatial model that combines rock geochemistry with lithology and topography demonstrates that average rock N reservoirs range from 0.18 to 1.2 kg N m-3 (80 to 534 mg N kg-1) across the nine geomorphic provinces of California and estimates a rock N denudation flux of 20-92 Gg yr-1 across the entire study area (natural atmospheric inputs ~ 140 Gg yr-1). The model highlights regional differences in rock N mobilization and points to the Coast Ranges, Transverse Ranges, and the Klamath Mountains as regions where rock N could contribute meaningfully to ecosystem N cycling. Contrasting these data to global compilations suggests that our findings are broadly applicable beyond California and that the N abundance and variability in rock are well constrained across most of the Earth system.

  10. Geothermal Reservoir Engineering Research. Fourth annual report, October 1, 1983-September 30, 1984

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Brigham, W.E.; Miller, F.G.

    1984-09-01

    Reservoir definition research consisted of well test analysis and bench-scale experiments. Well testing included both single-well pressure drawdown and buildup testing, and multiple-well interference testing. The development of new well testing methods continued to receive major emphasis during the year. Work included a project on multiphase compressibility, including the thermal content of the rock. Several projects on double-porosity systems were completed, and work was done on relative-permeability. Heat extraction from rock will determine the long-term response of geothermal reservoirs to development. The work in this task area involved a combination of physical and mathematical modeling of heat extraction from fractured geothermal reservoirs. International cooperative research dealt with adsorption of water on reservoir cores, the planning of tracer surveys, and an injection and tracer test in the Los Azufres fields. 32 refs.

  11. Super viscous oil reservoir formations of Ufa unit of Republic of Tatarstan and their properties

    Science.gov (United States)

    Osipova, D.; Vafin, R.; Surmashev, R.; Bondareva, O.

    2012-04-01

    Over 450 concentrations of super viscous oils (SVO) were discovered in Tatarstan for the time being. All of them are related to productive deposits of Permian period occurred at depths up to 300-400 metres consisting of terrigenous and carbonate deposits. Described are reservoir formations of the fields where recoverable reserves of SVO are confined by argillo-arenaceous thickness of Ufa terrigenous unit. Studying reservoir properties was based on laboratory analysis of core samples in terms of: Macro- and microscopic description, grain-size analysis, determination of effective porosity, permeability, volumetric and weight oil saturation, carbonate content, mineralogical density. According to macro-analysis data, thickness cross-section presents sandstones with rare interlayer and lenticle of siltstones and clays. The colour of calcareous sandstones varies from grey to black. Incoherent rocks prevail while closely consolidated types are rarely observed. The grain-size analysis revealed that 0.25-0.1 mm size grains are dominated in the sandstone composition, their concentration in rocks amounts to 69% that enables belonging oil rocks to fine-grained sandstones. Reservoir properties of rocks widely vary as follows: Effective porosity varies from 2.4 to 44.5% (average 31.5%), carbonate content from 0.6 to 30.1% (average 6.7%), mineralogical density from 2.3 to 3.3% (average 2.7%), and oil saturation from 0.1 to 14.9 rock weight % (average 7.8%). Reservoir porosities of reservoirs correlate to each other. Correlations between porosities are set in logarithmic values. Good direct correlation dependence (coefficient of correlation 0.5352) was identified between porosity and permeability as well as clear inverse relation between carbonate content and porosity (coefficient of correlation = - 0.7659). More tight positive correlation is observed for Porosity - Mass oil saturation (coefficient of correlation 0. 75087). This correlation indicates that super viscous oils are

  12. Advanced waterflooding in chalk reservoirs: Understanding of underlying mechanisms

    DEFF Research Database (Denmark)

    Zahid, Adeel; Sandersen, Sara Bülow; Stenby, Erling Halfdan

    2011-01-01

    Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recove...... of a microemulsion phase could be the possible reasons for the observed increase in oil recovery with sulfate ions at high temperature in chalk reservoirs besides the mechanism of the rock wettability alteration, which has been reported in most previous studies.......Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recovery...

  13. Full Waveform Inversion for Reservoir Characterization - A Synthetic Study

    KAUST Repository

    Zabihi Naeini, E.

    2017-05-26

    Most current reservoir-characterization workflows are based on classic amplitude-variation-with-offset (AVO) inversion techniques. Although these methods have generally served us well over the years, here we examine full-waveform inversion (FWI) as an alternative tool for higher-resolution reservoir characterization. An important step in developing reservoir-oriented FWI is the implementation of facies-based rock physics constraints adapted from the classic methods. We show that such constraints can be incorporated into FWI by adding appropriately designed regularization terms to the objective function. The advantages of the proposed algorithm are demonstrated on both isotropic and VTI (transversely isotropic with a vertical symmetry axis) models with pronounced lateral and vertical heterogeneity. The inversion results are explained using the theoretical radiation patterns produced by perturbations in the medium parameters.

  14. Principles of rock mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Turchaninov, I.A.; Iofis, M.A.; Kasparyan, E.V.

    1979-01-01

    This book presents the principles of rock mechanics in a systematic way, reflecting both the historic development and the contemporary status of theoretical and experimental techniques used for the determination of the properties and stress state of rock masses, calculation of elements of systems for exploitation of useful mineral deposits and the design of mine openings. The subject of rock mechanics is discussed and methods and basic approaches are analyzed. The most widely used methods for determining the properties of rock in specimens and in situ are described. Problems of determining the stress strain state of the rock around mine openings by both experimental and analytic methods are discussed. The primary results of the study of the stress state of rock around main, development and production openings are presented. Problems of the movement of rock due to extraction of minerals are analyzed in detail, as are the conditions and causes of the development of rock bursts and sudden release of rock and gas in both surface and underground mines. Procedures for preventing or localizing rock bursts or sudden outbursts are described. (313 refs.)

  15. Hot dry rock venture risks investigation:

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    This study assesses a promising resource in central Utah as the potential site of a future commerical hot dry rock (HDR) facility for generating electricity. The results indicate that, if the HDR reservoir productivity equals expectations based on preliminary results from research projects to date, a 50 MWe HDR power facility at Roosevelt Hot Springs could generate power at cost competitive with coal-fired plants. However, it is imperative that the assumed productivity be demonstrated before funds are committed for a commercial facility. 72 refs., 39 figs., 38 tabs.

  16. Recent Development in Numerical Simulation of Enhanced Geothermal Reservoirs

    Institute of Scientific and Technical Information of China (English)

    Huilin Xing; Yan Liu; Jinfang Gao; Shaojie Chen

    2015-01-01

    This paper briefly introduces the current state in computer modelling of geothermal reservoir system and then focuses on our research efforts in high performance simulation of en-hanced geothermal reservoir system. A novel supercomputer simulation tool has been developing towards simulating the highly non-linear coupled geomechanical-fluid flow-thermal systems involv-ing heterogeneously fractured geomaterials at different spatial and temporal scales. It is applied here to simulate and visualise the enhanced geothermal system (EGS), such as (1) visualisation of the microseismic events to monitor and determine where/how the underground rupture proceeds during a hydraulic stimulation, to generate the mesh using the recorded data for determining the domain of the ruptured zone and to evaluate the material parameters (i.e., the permeability) for the further numerical analysis and evaluation of the enhanced geothermal reservoir; (2) converting the avail-able fractured rock image/fracture data as well as the reservoir geological geometry to suitable meshes/grids and further simulating the fluid flow in the complicated fractures involving the de-tailed description of fracture dimension and geometry by the lattice Boltzmann method and/or finite element method;(3) interacting fault system simulation to determine the relevant complicated rup-ture process for evaluating the geological setting and the in-situ reservoir properties; (4) coupled thermo-fluid flow analysis of a geothermal reservoir system for an optimised geothermal reservoir design and management. A few of application examples are presented to show its usefulness in simu-lating the enhanced geothermal reservoir system.

  17. Geologic Characteristics of Gas Reservoirs in West Sichuan Foreland Basin

    Institute of Scientific and Technical Information of China (English)

    YANG Keming

    2008-01-01

    The foreland basin in West Sichuan is a tectonic unit that has undergone multi-periods tectonic movements of Indosinian-Yanshanian-Himalayan. Since late Triassic, it has been in a passive subsidence environment controlled by basin margin mountain systems and by the compression with abundant sediment sources. With the complex geologic setting, the main geologic characteristics of natural gas reservoir are listed as following:(1)Source rocks are coal-bearing mud and shale series with high to over maturity, and long and progressive hydrocarbon generation-displacement period. The key accumulation period is middle-late Yanshanian epoch.(2)There are three gas-bearing systems vertically, each of which has different reservoir mechanism, main-controlled factors and distribution law, so the exploration thoughts and techniques are also different.(3)Undergoing multi-period generation-migration-accumulation, oil and gas have encountered multi-period modification or destruction, and gas accumulation overpass multiple tectonic periods. So the trap type is complicated and dominated by combination traps. Because the main accumulation period of natural gas is early and the reservoir encountered the modification of strong Himalayan movement, there is great difference in the fullness degree of gas reservoirs and complicated gas-water relation. (4) Reservoir is tight to very tight, but reservoirs of relatively high quality developed under the super tight setting. (5) The key techniques for oil and gas exploration in west Sichuan foreland basin are the prediction of relatively favorable reservoirs, fractures and gas bearing; and the key techniques for oil and gas development are how to improve the penetration rate, reservoir protection and modification.

  18. US production of natural gas from tight reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-18

    For the purposes of this report, tight gas reservoirs are defined as those that meet the Federal Energy Regulatory Commission`s (FERC) definition of tight. They are generally characterized by an average reservoir rock permeability to gas of 0.1 millidarcy or less and, absent artificial stimulation of production, by production rates that do not exceed 5 barrels of oil per day and certain specified daily volumes of gas which increase with the depth of the reservoir. All of the statistics presented in this report pertain to wells that have been classified, from 1978 through 1991, as tight according to the FERC; i.e., they are ``legally tight`` reservoirs. Additional production from ``geologically tight`` reservoirs that have not been classified tight according to the FERC rules has been excluded. This category includes all producing wells drilled into legally designated tight gas reservoirs prior to 1978 and all producing wells drilled into physically tight gas reservoirs that have not been designated legally tight. Therefore, all gas production referenced herein is eligible for the Section 29 tax credit. Although the qualification period for the credit expired at the end of 1992, wells that were spudded (began to be drilled) between 1978 and May 1988, and from November 5, 1990, through year end 1992, are eligible for the tax credit for a subsequent period of 10 years. This report updates the EIA`s tight gas production information through 1991 and considers further the history and effect on tight gas production of the Federal Government`s regulatory and tax policy actions. It also provides some high points of the geologic background needed to understand the nature and location of low-permeability reservoirs.

  19. Hydraulic Fracture Stimulation Treatments at East Mesa, Well 58-30; Geothermal Reservoir Well Stimulation Program; Experiment 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-02-01

    The tests reported were part of the DOE Geothermal Reservoir Well Stimulation Program. This East Mesa (Imperial Valley, CA) well was successfully stimulated with two fracture treatments, a dendritic fracture and a planar fracture. The natural flow production of the well increased 114 percent, to 197,900 lb/hr. These tests were among the few successful attempts of this program to increase flow from geothermal production wells. The general belief is that these tests worked OK primarily because the formation was sedimentary rock (similar to rock in most oil and gas wells that have been stimulated successfully. Similar tests in geothermal hard rock reservoirs did not work very well. (DJE 2005)

  20. Proceedings of the twenty-first workshop on geothermal reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This document contains the Proceedings of the Twenty-first Workshop in Geothermal Reservoir Engineering, held at Stanford University, Stanford, California, USA, January 22-24, 1996. Sixty-six papers were presented in the technical sessions of the workshop. Technical papers were organized into twenty sessions including: reservoir assessment, modeling, geology/geochemistry, fracture modeling/hot-dry-rock, low enthalpy, fluid injection, well testing, drilling, adsorption, and well stimulation.

  1. Imaging pore space in tight gas sandstone reservoir: insights from broad ion beam cross-sectioning

    OpenAIRE

    Konstanty J.; Kukla P.A.; Urai J.L.; Baerle C.; Enzmann F.; Desbois G.

    2010-01-01

    Monetization of tight gas reservoirs, which contain significant gas reserves world-wide, represents a challenge for the entire oil and gas industry. The development of new technologies to enhance tight gas reservoir productivity is strongly dependent on an improved understanding of the rock properties and especially the pore framework. Numerous methods are now available to characterize sandstone cores. However, the pore space characterization at pore scale remains difficult due to the f...

  2. Statistically Based Inference of Physical Rock Properties of Main Rock Types in Germany

    Science.gov (United States)

    Koch, A.; Jorand, R.; Clauser, C.

    2009-12-01

    A major obstacle for an increased use of geothermal energy often lies in the high success risk for the development of geothermal reservoirs due to the unknown rock properties. In general, the ranges of thermal and hydraulic properties (thermal conductivity, volumetric heat capacity, porosity, permeability) in existing compilations of rock properties are too large to be useful to constrain properties for specific sites. Usually, conservative assumptions are made about these properties, resulting in greater drilling depth and increased exploration cost. In this study, data from direct measurements on more than 600 core samples from different borehole locations and depths enable to derive statistical moments of the desired properties for selected main rock types in the German subsurface. Using modern core scanning technology allowed measuring rapidly thermal conductivity, sonic velocity, and gamma density with high resolution on a large number of samples. In addition, we measured porosity, bulk density, and matrix density based on Archimedes’ principle and pycnometer analysis. Tests on a smaller collection of samples also include specific heat capacity, hydraulic permeability, and radiogenic heat production rate. In addition, we complemented the petrophysical measurements by quantitative mineralogical analysis. The results reveal that even for the same main rock type the results differ significantly depending on geologic age, origin, compaction, and mineralogical composition. For example, water saturated thermal conductivity of tight Palaeozoic sandstones from the Lower Rhine Embayment and the Ruhr Area is 4.0±0.7 W m-1 K-1 and 4.6±0.6 W m-1 K-1, respectively, which is nearly identical to values for the Lower Triassic Bunter sandstone in Southwest-Germany (high in quartz showing an average value of 4.3±0.4 W m-1 K-1). In contrast, saturated thermal conductivity of Upper Triassic sandstone in the same area is considerably lower at 2.5±0.1 W m-1 K-1 (Schilf

  3. Status of Blue Ridge Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  4. Relations between seismic signals and reservoir properties of tight gas reservoirs in North Germany (Permian Rotliegend sandstones)

    Energy Technology Data Exchange (ETDEWEB)

    Abram, P.; Gaupp, R. [Friedrich-Schiller-Univ., Inst. of Geosciences, Jena (Germany)

    2006-07-01

    Tight gas reservoirs in North Germany consist of sandstones of eolian, fluvial and lacustrine origin in 3,5-5 km (11500-16500 ft) depth. Different mechanical compaction, mineral authigenesis and cement dissolution resulted in proximate zones with good and poor reservoir qualities. Some regions with moderate porosities provide very low permeabilities whereas regions with low porosities can offer profitable permeabilities within comparable depositional lithologies. Therefore deep gas exploration is very dependent on predictive reservoir information from 3D seismic signals due to the locally varying reservoir qualities. A recent study succeeded in subdividing a tight gas reservoir into parts with good, moderate and poor qualities and to predict reservoir properties for parts without well information. For this purpose 3D seismic signals had been classified with Neural Network techniques based on amplitude, shape and lateral coherency of seismic traces. The unsupervised classification (Kohonen map) with a single layer of neurons generated classes, which are representative for seismic wave and rock properties at the reservoir level. The geographical distribution of these seismic facies classes correlates to locations of wells with either good or poor reservoir qualities and to zones of specific petrophysical, petrological and sedimentological data. Wells with mean permeabilities between 9-50 mD are located within the red areas (seismic classes 6 and 7), while wells with mean permeabilities below 0,5 mD are all found in blue and green areas (seismic classes 1 till 4). Furthermore, the red zone in the East corresponds to the eastern part of a production field of high transmissivity. The main reason for the strong reduction in mean permeability was found to be a specific morphotype of authigenic illite which occurs almost only in the blue and green zones. This paper outlines SOME theories and results of the doctoral thesis.

  5. The use of polar angle, polar arm and other physical attributes in rock characterization

    Directory of Open Access Journals (Sweden)

    M.S. Benzagouta

    2015-07-01

    Full Text Available Sandstone reservoirs and other rock type properties can be variable from the time of deposition up to their burial. Rock texture and structure in addition to diagenetic changes control the reservoir characteristics, fluid flow and accumulation during the sediment burial process. In this study, investigation is concerned with the determination of selected samples petrophysical characteristics and their relation to some of the physical properties. These properties constitute an essential constraint. Particular focus will concentrate on the determination of the reservoir characterization and their correlation to the determined polar angle and polar arm. Accomplishment of this target is accustomed to the determination of other physical attributes properties. Among targeted attributes state the rock quality index (RQI associated to the flow zone indicator (FZI and the fractal dimension (Df. The overall is intended to make an attempt for reservoir description leading to its qualitative and quantitative assessment. Thus, the anticipated rock and fluid properties including polar angle and polar arm parameters are of fine prediction towards reliable information on the considered samples. As a result, in the case study, aimed factors have proved diverse statements. They were of a big contribution towards the reservoir quality index, its heterogeneity and the rock type porosity. They were also of big interest in proving the fluid flow circulation rate and storage.

  6. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Menzie, D.E.

    1995-05-01

    The main objective of this research project is to investigate dispersion as a method of quantifying geological characterization and defining reservoir heterogeneity in order to enhance crude oil recovery. The dispersion of flow of a reservoir rock (dispersion coefficient and dispersivity) was identified as one of the physical properties of a reservoir rock by measuring the mixing of two miscible fluids, one displacing the other in a porous medium. A rock was 100% saturated with a resident fluid and displaced by a miscible fluid of equal viscosity and equal density. Some specific experiments were performed with unequal densities. Produced fluid was analyzed by refractometer, nuclear reaction, electrical conductivity and X-ray scan. Several physical and flow characteristics were measured on the sand rock sample in order to establish correlations with the measured dispersion property. Absolute permeability, effective porosity, relative permeability, capillary pressure, the heterogeneity factor and electrical conductivity were used to better understand the flow system. Linear, transverse, 2-D and 3-D dispersions were measured and used to characterize the rock heterogeneity of the flow system. A new system of measuring dispersion was developed using a gas displacing gas system in a porous medium. An attempt was also made to determine the dispersion property of an actual reservoir from present day well log data on a producing well. 275 refs., 102 figs., 17 tabs.

  7. Direct quantification of long-term rock nitrogen inputs to temperate forest ecosystems.

    Science.gov (United States)

    Morford, Scott L; Houlton, Benjamin Z; Dahlgren, Randy A

    2016-01-01

    Sedimentary and metasedimentary rocks contain large reservoirs of fixed nitrogen (N), but questions remain over the importance of rock N weathering inputs in terrestrial ecosystems. Here we provide direct evidence for rock N weathering (i.e., loss of N from rock) in three temperate forest sites residing on a N-rich parent material (820-1050 mg N kg(-1); mica schist) in the Klamath Mountains (northern California and southern Oregon), USA. Our method combines a mass balance model of element addition/ depletion with a procedure for quantifying fixed N in rock minerals, enabling quantification of rock N inputs to bioavailable reservoirs in soil and regolith. Across all sites, -37% to 48% of the initial bedrock N content has undergone long-term weathering in the soil. Combined with regional denudation estimates (sum of physical + chemical erosion), these weathering fractions translate to 1.6-10.7 kg x ha(-1) x yr(-1) of rock N input to these forest ecosystems. These N input fluxes are substantial in light of estimates for atmospheric sources in these sites (4.5-7.0 kg x ha(-1) x yr(-1)). In addition, N depletion from rock minerals was greater than sodium, suggesting active biologically mediated weathering of growth-limiting nutrients compared to nonessential elements. These results point to regional tectonics, biologically mediated weathering effects, and rock N chemistry in shaping the magnitude of rock N inputs to the forest ecosystems examined.

  8. Geothermal reservoir categorization and stimulation study

    Energy Technology Data Exchange (ETDEWEB)

    Overton, H.L.; Hanold, R.J.

    1977-07-01

    Analyses of the fraction of geothermal wells that are dry (dry-hole fraction) indicate that geothermal reservoirs can be fitted into four basic categories: (i) Quaternary to late Tertiary sediments (almost no dry holes); (ii) Quaternary to late Tertiary extrusives (approximately 20 percent dry holes); (iii) Mesozoic or older metamorphic rocks (approximately 25-30 percent dry holes); and (iv) Precambrian or younger rocks (data limited to Roosevelt Springs where 33 percent of the wells were dry). Failure of geothermal wells to flow economically is due mainly to low-permeability formations in unfractured regions. Generally the permeability correlates inversely with the temperature-age product and directly with the original rock porosity and pore size. However, this correlation fails whenever high-stress fields provide vertical fracturing or faulting, and it is the high-stress/low-permeability category that is most amenable to artificial stimulation by hydraulic fracturing, propellant fracturing, or chemical explosive fracturing. Category (i) geothermal fields (e.g., Cerro Prieto, Mexico; Niland, CA; East Mesa, CA) are not recommended for artificial stimulation because these younger sediments almost always produce warm or hot water. Most geothermal fields fit into category (ii) (e.g., Wairakei, New Zealand; Matsukawa, Japan; Ahuachapan, El Salvador) and in the case of Mt. Home, ID, and Chandler, AZ, possess some potential for stimulation. The Geysers is a category (iii) field, and its highly stressed brittle rocks should make this site amenable to stimulation by explosive fracturing techniques. Roosevelt Springs, UT, well 9-1 is in category (iv) and is a flow failure. It represents a prime candidate for stimulation by hydraulic fracturing because it has a measured temperature of 227/sup 0/C, is cased and available for experimentation, and is within 900 m of an excellent geothermal producing well.

  9. Scaling minerals from deep-seated granitic geothermal reservoir

    Science.gov (United States)

    Yanagisawa, Norio

    2016-04-01

    To promote geothermal energy use and sustainable production, the information of scaling situation from deep-seated geothermal reservoir is important. In Japan, at the Kakkonda geothermal field, Iwate prefecture, north-eastern of Japan, there is 80MW geothermal power plant using about 300 degree C fluid from the reservoir at the boundary between Quaternary Kakkonda granite and Pre-Tertiary formations about 3km depth and more deep-seated reservoir survey was carried out by NEDO. Then, to understand the mechanism of deep-seated reservoir, we survey the metal sulphide minerals deposited at production wellhead and pipeline and compare with the brine And the brine of WD-1a at 3.7km depth, into Quaternary Kakkonda granite rock. In Kakkonda geothermal system, the scales are classified into two types based on sulphide mineralogy, which are Pb-Zn rich type and Cu rich type. Pb-Zn rich scales, for example galena (PbS) and Sphalerite (ZnS), are found in Well-19 located at the marginal part of the Kakkonda granite And Cu-rich scales, for example chalcocite (Cu2S), loellingite (FeAs2) and native antimony (Sb), are found in Well-13, located at the central part of the Kakkonda granite. And the brine of WD-1a at 3.7km depth about 500 degree C, into Quaternary Kakkonda granite rock near Well-19 is rich in Pb and Zn and similar composition as the Well-19 scale. Therefore, deep reservoir of Kakkonda field evolves with mixing the fluid of shallow reservoir and the brine of occurred in the Quaternary Kakkonda granite. Then, the existence of both Pb-Zn rich scale and Cu rich scale is a characteristic feature of Kakkonda geothermal and this fact suggest to have similar zoning as found in Porphyry Copper Zoning. On progress of production the fluids from deep reservoir continue to be suffered by the fluid of shallow reservoir and meteoritic water. With temperature of production well decreasing and chemical composition changed, silica precipitation decreased and the metal sulfide mineral

  10. Fault controlled geochemical properties in Lahendong geothermal reservoir Indonesia

    Science.gov (United States)

    Brehme, Maren; Deon, Fiorenza; Haase, Christoph; Wiegand, Bettina; Kamah, Yustin; Sauter, Martin; Regenspurg, Simona

    2016-03-01

    Rock and fluid geochemical data from Lahendong, Indonesia, were analyzed to evaluate the influence of fault zones on reservoir properties. It was found that these properties depend on fault-permeability controlled fluid flow. Results from measurements of spring and well water as well as rocks and their hydraulic properties were combined with hydrochemical numerical modeling. The models show that the geothermal field consists of two geochemically distinct reservoir sections. One section is characterized by acidic water, considerable gas discharge and high geothermal-power productivity—all related to increased fault zone permeability. The other section is characterized by neutral water and lower productivity. Increased fluid flow in the highly fractured and permeable areas enhances chemical reaction rates. This results in strong alteration of their surrounding rocks. Numerical models of reactions between water and rock at Lahendong indicate the main alteration products are clay minerals. A geochemical conceptual model illustrates the relation between geochemistry and permeability and their distribution within the area. Our conceptual model illustrates the relation between geochemistry and fault-zone permeability within the Lahendong area. Further mapping of fault-related permeability would support sustainable energy exploitation by avoiding low-productive wells or the production of highly corroding waters, both there and elsewhere in the world.

  11. Identification of Parameters of a Fractured-Porous Reservoir by the Data of Unsteady Fluid Inflow to Vertical Wells

    Science.gov (United States)

    Sadovnikov, R. V.

    2016-09-01

    The author proposes a numerical algorithm to indentify filtration and capacitory parameters of a fractured-porous reservoir by the results of hydrodynamic investigations of the well on the basis of the Levenberg-Marquardt method, which belongs to the methods of minimization of second order. The algorithm makes it possible to determine the total set of such parameters of a fractured-porous reservoir as the permeability coefficients of fractures and blocks, the parameters of fluid crossflow between blocks and fractures, the characteristic delay times, the linear dimension of matrix blocks of rock, the piezoconductivity coefficients of blocks and fractures of the reservoir, the reservoir pressure, and the efficiency of the well.

  12. Soft rocks in Argentina

    Institute of Scientific and Technical Information of China (English)

    Giambastiani; Mauricio

    2014-01-01

    Soft rocks are a still fairly unexplored chapter in rock mechanics. Within this category are the clastic sedimentary rocks and pyroclastic volcanic rocks, of low to moderate lithification (consolidation, cemen-tation, new formed minerals), chemical sedimentary rocks and metamorphic rocks formed by minerals with Mohs hardness less than 3.5, such as limestone, gypsum, halite, sylvite, between the first and phyllites, graphitic schist, chloritic shale, talc, etc., among the latter. They also include any type of rock that suffered alteration processes (hydrothermal or weathering). In Argentina the study of low-strength rocks has not received much attention despite having extensive outcrops in the Andes and great impact in the design criteria. Correlation between geomechanical properties (UCS, deformability) to physical index (porosity, density, etc.) has shown promising results to be better studied. There are many studies and engineering projects in Argentina in soft rock geological environments, some cited in the text (Chihuído dam, N. Kirchner dam, J. Cepernic Dam, etc.) and others such as International Tunnel in the Province of Mendoza (Corredor Bioceánico), which will require the valuable contribution from rock mechanics. The lack of consistency between some of the physical and mechanical parameters explored from studies in the country may be due to an insufficient amount of information and/or non-standardization of criteria for testing materials. It is understood that more and better academic and professional efforts in improv-ing techniques will result in benefits to the better understanding of the geomechanics of weak rocks.

  13. Effect of Hydrothermal Alteration on Rock Properties in Active Geothermal Setting

    Science.gov (United States)

    Mikisek, P.; Bignall, G.; Sepulveda, F.; Sass, I.

    2012-04-01

    Hydrothermal alteration records the physical-chemical changes of rock and mineral phases caused by the interaction of hot fluids and wall rock, which can impact effective permeability, porosity, thermal parameters, rock strength and other rock properties. In this project, an experimental approach has been used to investigate the effects of hydrothermal alteration on rock properties. A rock property database of contrastingly altered rock types and intensities has been established. The database details horizontal and vertical permeability, porosity, density, thermal conductivity and thermal heat capacity for ~300 drill core samples from wells THM12, THM13, THM14, THM17, THM18, THM22 and TH18 in the Wairakei-Tauhara geothermal system (New Zealand), which has been compared with observed hydrothermal alteration type, rank and intensity obtained from XRD analysis and optical microscopy. Samples were selected from clay-altered tuff and intercalated siltstones of the Huka Falls Formation, which acts as a cap rock at Wairakei-Tauhara, and tuffaceous sandstones of the Waiora Formation, which is a primary reservoir-hosting unit for lateral and vertical fluid flows in the geothermal system. The Huka Falls Formation exhibits argillic-type alteration of varying intensity, while underlying Waiora Formations exhibits argillic- and propylithic-type alteration. We plan to use a tempered triaxial test cell at hydrothermal temperatures (up to 200°C) and pressures typical of geothermal conditions, to simulate hot (thermal) fluid percolation through the rock matrix of an inferred "reservoir". Compressibility data will be obtained under a range of operating (simulation reservoir) conditions, in a series of multiple week to month-long experiments that will monitor change in permeability and rock strength accompanying advancing hydrothermal alteration intensity caused by the hot brine interacting with the rock matrix. We suggest, our work will provide new baseline information concerning

  14. A Reservoir Assessment of the Geysers Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Richard P.; Chapman, Rodger H.; Dykstra, Herman; Stockton, A.D.

    1981-01-01

    Big Sulphur Creek fault zone, in The Geysers Geothermal field, may be part of a deep-seated, wrench-style fault system. Hydrothermal fluid reservoir may rise through conduits beneath the five main anomalies associated with the Big Sulphur Creek wrench trend. Upon moderately dipping, fracture network. Condensed steam at the steep reservoir flank drains back to the hot water table. These flanks are defined roughly by marginally-producing geothermal wells. Field extensions are expected to be on the southeast and northwest. Some geophysical anomalies (electrical resistivity and audio-magnetotelluric) evidently are caused by the hot water geothermal field or zones of altered rocks; others (gravity, P-wave delays, and possibly electrical resistivity) probably represent the underlying heat source, a possible magma chamber; and others (microearthquake activity) may be related to the steam reservoir. A large negative gravity anomaly and a few low-resitivity anomalies suggest areas generally favorable for the presence of steam zones, but these anomalies apparently do not directly indicate the known steam reservoir. Monitoring gravity and geodetic changes with time and mapping microearthquake activity are methods that show promise for determining reservoir size, possible recharge, production lifetime, and other characteristics of the known stream field. Seismic reflection data may contribute to the efficient exploitation of the field by identifying fracture zones that serve as conduits for the steam. (DJE-2005)

  15. Direct hydrocarbon exploration and gas reservoir development technology

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Young Hoon; Oh, Jae Ho; Jeong, Tae Jin [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)] [and others

    1995-12-01

    In order to enhance the capability of petroleum exploration and development techniques, three year project (1994 - 1997) was initiated on the research of direct hydrocarbon exploration and gas reservoir development. This project consists of four sub-projects. (1) Oil(Gas) - source rock correlation technique: The overview of bio-marker parameters which are applicable to hydrocarbon exploration has been illustrated. Experimental analysis of saturated hydrocarbon and bio-markers of the Pohang E and F core samples has been carried out. (2) Study on surface geochemistry and microbiology for hydrocarbon exploration: the test results of the experimental device for extraction of dissolved gases from water show that the device can be utilized for the gas geochemistry of water. (3) Development of gas and gas condensate reservoirs: There are two types of reservoir characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. (4) Numerical modeling of seismic wave propagation and full waveform inversion: Three individual sections are presented. The first one is devoted to the inversion theory in general sense. The second and the third sections deal with the frequency domain pseudo waveform inversion of seismic reflection data and refraction data respectively. (author). 180 refs., 91 figs., 60 tabs.

  16. Stress Path Evolution Associated With CO2 Storage Reservoirs

    Science.gov (United States)

    Vilarrasa, V.; Gheibi, S.; Holt, R. M.; Lavrov, A.

    2015-12-01

    Safe storage of CO2 in geological formations is an essential part of CO2 sequestration projects. Pressure changes inside the formation cause effective and total stress changes inside and outside of those formations. These changes can bring the reservoir or its surroundings to failure conditions. The existence of faults and weak zones increases the likelihood of failure in rock masses depending on the amount of the injection-induced changes and the formation properties. This paper discusses the stress changes in different reservoir and injection conditions. Numerical analysis indicates that the pressure buildup can significantly change the total and effective stress and these changes are more severe when faults are present in the formation. Also, the reservoir and caprock experience a greater decrease in the mean effective stress and increase in the deviatoric stress in the footwall and hanging wall of a fault in reverse and normal faulting stress regimes, respectively. The stress path depends on the size of the CO2 plume, the pressure distribution inside the reservoir, and fault and reservoir properties.

  17. Rock Cycle Roulette.

    Science.gov (United States)

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  18. Evolution of the Petrophysical and Mineralogical Properties of Two Reservoir Rocks Under Thermodynamic Conditions Relevant for CO2 Geological Storage at 3 km Depth Évolution des propriétés physiques et minéralogiques de deux roches réservoirs dans des conditions thermodynamiques correspondant à un stockage géologique de CO2 à 3 km de profondeur

    Directory of Open Access Journals (Sweden)

    Rimmelé G.

    2009-11-01

    Full Text Available Injection of carbon dioxide (CO2 underground, for long-term geological storage purposes, is considered as an economically viable option to reduce greenhouse gas emissions in the atmosphere. The chemical interactions between supercritical CO2 and the potential reservoir rock need to be thoroughly investigated under thermodynamic conditions relevant for geological storage. In the present study, 40 samples of Lavoux limestone and Adamswiller sandstone, both collected from reservoir rocks in the Paris basin, were experimentally exposed to CO2 in laboratory autoclaves specially built to simulate CO2-storage-reservoir conditions. The two types of rock were exposed to wet supercritical CO2 and CO2-saturated water for one month, at 28 MPa and 90°C, corresponding to conditions for a burial depth approximating 3 km. The changes in mineralogy and microtexture of the samples were measured using X-ray diffraction analyses, Raman spectroscopy, scanning-electron microscopy, and energy-dispersionspectroscopy microanalysis. The petrophysical properties were monitored by measuring the weight, density, mechanical properties, permeability, global porosity, and local porosity gradients through the samples. Both rocks maintained their mechanical and mineralogical properties after CO2 exposure despite an increase of porosity and permeability. Microscopic zones of calcite dissolution observed in the limestone are more likely to be responsible for such increase. In the sandstone, an alteration of the petrofabric is assumed to have occurred due to clay minerals reacting with CO2. All samples of Lavoux limestone and Adamswiller sandstone showed a measurable alteration when immersed either in wet supercritical CO2 or in CO2-saturated water. These batch experiments were performed using distilled water and thus simulate more severe conditions than using formation water (brine. L’injection de dioxyde de carbone (CO2 en sous-sol pour un stockage géologique à long terme

  19. The Stimulation of Hydrocarbon Reservoirs with Subsurface Nuclear Explosions

    Energy Technology Data Exchange (ETDEWEB)

    LORENZ,JOHN C.

    2000-12-08

    Between 1965 and 1979 there were five documented and one or more inferred attempts to stimulate the production from hydrocarbon reservoirs by detonating nuclear devices in reservoir strata. Of the five documented tests, three were carried out by the US in low-permeability, natural-gas bearing, sandstone-shale formations, and two were done in the USSR within oil-bearing carbonates. The objectives of the US stimulation efforts were to increase porosity and permeability in a reservoir around a specific well by creating a chimney of rock rubble with fractures extending beyond it, and to connect superimposed reservoir layers. In the USSR, the intent was to extensively fracture an existing reservoir in the more general vicinity of producing wells, again increasing overall permeability and porosity. In both countries, the ultimate goals were to increase production rates and ultimate recovery from the reservoirs. Subsurface explosive devices ranging from 2.3 to about 100 kilotons were used at depths ranging from 1208 m (3963 ft) to 2568 m (8427 ft). Post-shot problems were encountered, including smaller-than-calculated fracture zones, formation damage, radioactivity of the product, and dilution of the BTU value of tie natural gas with inflammable gases created by the explosion. Reports also suggest that production-enhancement factors from these tests fell short of expectations. Ultimately, the enhanced-production benefits of the tests were insufficient to support continuation of the pro-grams within increasingly adversarial political, economic, and social climates, and attempts to stimulate hydrocarbon reservoirs with nuclear devices have been terminated in both countries.

  20. Data Integration for the Generation of High Resolution Reservoir Models

    Energy Technology Data Exchange (ETDEWEB)

    Albert Reynolds; Dean Oliver; Gaoming Li; Yong Zhao; Chaohui Che; Kai Zhang; Yannong Dong; Chinedu Abgalaka; Mei Han

    2009-01-07

    The goal of this three-year project was to develop a theoretical basis and practical technology for the integration of geologic, production and time-lapse seismic data in a way that makes best use of the information for reservoir description and reservoir performance predictions. The methodology and practical tools for data integration that were developed in this research project have been incorporated into computational algorithms that are feasible for large scale reservoir simulation models. As the integration of production and seismic data require calibrating geological/geostatistical models to these data sets, the main computational tool is an automatic history matching algorithm. The following specific goals were accomplished during this research. (1) We developed algorithms for calibrating the location of the boundaries of geologic facies and the distribution of rock properties so that production and time-lapse seismic data are honored. (2) We developed and implemented specific procedures for conditioning reservoir models to time-lapse seismic data. (3) We developed and implemented algorithms for the characterization of measurement errors which are needed to determine the relative weights of data when conditioning reservoir models to production and time-lapse seismic data by automatic history matching. (4) We developed and implemented algorithms for the adjustment of relative permeability curves during the history matching process. (5) We developed algorithms for production optimization which accounts for geological uncertainty within the context of closed-loop reservoir management. (6) To ensure the research results will lead to practical public tools for independent oil companies, as part of the project we built a graphical user interface for the reservoir simulator and history matching software using Visual Basic.

  1. Enhanced characterization of reservoir hydrocarbon components using electromagnetic data attributes

    KAUST Repository

    Katterbauer, Klemens

    2015-12-23

    Advances in electromagnetic imaging techniques have led to the growing utilization of this technology for reservoir monitoring and exploration. These exploit the strong conductivity contrast between the hydrocarbon and water phases and have been used for mapping water front propagation in hydrocarbon reservoirs and enhancing the characterization of the reservoir formation. The conventional approach for the integration of electromagnetic data is to invert the data for saturation properties and then subsequently use the inverted properties as constraints in the history matching process. The non-uniqueness and measurement errors may however make this electromagnetic inversion problem strongly ill-posed, leading to potentially inaccurate saturation profiles. Another limitation of this approach is the uncertainty of Archie\\'s parameters in relating rock conductivity to water saturation, which may vary in the reservoir and are generally poorly known. We present an Ensemble Kalman Filter framework for efficiently integrating electromagnetic data into the history matching process and for simultaneously estimating the Archie\\'s parameters and the variance of the observation error of the electromagnetic data. We apply the proposed framework to a compositional reservoir model. We aim at assessing the relevance of EM data for estimating the different hydrocarbon components of the reservoir. The experimental results demonstrate that the individual hydrocarbon components are generally well matched, with nitrogen exhibiting the strongest improvement. The estimated observation error standard deviations are also within expected levels (between 5 and 10%), significantly contributing to the robustness of the proposed EM history matching framework. Archie\\'s parameter estimates approximate well the reference profile and assist in the accurate description of the electrical conductivity properties of the reservoir formation, hence leading to estimation accuracy improvements of around

  2. Geothermal reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, C.R.; Golabi, K.

    1978-02-01

    The optimal management of a hot water geothermal reservoir was considered. The physical system investigated includes a three-dimensional aquifer from which hot water is pumped and circulated through a heat exchanger. Heat removed from the geothermal fluid is transferred to a building complex or other facility for space heating. After passing through the heat exchanger, the (now cooled) geothermal fluid is reinjected into the aquifer. This cools the reservoir at a rate predicted by an expression relating pumping rate, time, and production hole temperature. The economic model proposed in the study maximizes discounted value of energy transferred across the heat exchanger minus the discounted cost of wells, equipment, and pumping energy. The real value of energy is assumed to increase at r percent per year. A major decision variable is the production or pumping rate (which is constant over the project life). Other decision variables in this optimization are production timing, reinjection temperature, and the economic life of the reservoir at the selected pumping rate. Results show that waiting time to production and production life increases as r increases and decreases as the discount rate increases. Production rate decreases as r increases and increases as the discount rate increases. The optimal injection temperature is very close to the temperature of the steam produced on the other side of the heat exchanger, and is virtually independent of r and the discount rate. Sensitivity of the decision variables to geohydrological parameters was also investigated. Initial aquifer temperature and permeability have a major influence on these variables, although aquifer porosity is of less importance. A penalty was considered for production delay after the lease is granted.

  3. Technology for the Utilization of Deep Geothermal Reservoirs in Germany

    Directory of Open Access Journals (Sweden)

    David Bruhn

    2007-01-01

    Full Text Available The Geothermal Technology Program at GFZ identify suitable geological structures and horizons for extracting energy and develop new methods to increase the productivity of deep geothermal reservoirs. In this context, the former gas exploration well Groß Schönebeck EGrSk3/90 (50 km northeast of Berlin was reopened and deepened to the 4309 m depth to serve as a geothermal in situ laboratory for testing stimulation concepts. The objective of these stimulation operations was to create secondary flow paths and to improve the inflow performance of the well.In addition, Groß Schönebeck is the only test site of the EU-project I-GET (Integrated Geophysical Exploration Technologies for deep fractured geothermal systems, where new, cost-effective and reliable geothermal exploration techniques are developed to increase the success rate of drilling.Based on the data of deep neighbouring wells and the industry seismic measurements, a model was generated to visualise the geological setting and to plan the course of the second well. The well encounters a typical sequence of various geological formations, known in the North German Basin. A series of 2370 m of Quaternary to Triassic sediments is underlain by 1492 m of Zechstein salts, and the following section of this well, which was foreseen for testing, comprises 400 m of Rotliegend formation (siltstones, sandstones, conglomerates and 60 m of underlying volcanic rocks down to the final depth of 4309 m.The well Groß Schönebeck makes the deep sedimentary Rotliegend reservoir accessible, which is characterized by water bearing porous and fractured rocks. The Rotliegend reservoir consists of a sequence of sandstones, conglomerates, and volcanic rocks with formation fluids of 150 °C at porosities of up to 10 %. Experiments in this in-situ geothermal laboratory should lead to a reliable technology for a sufficient production of deep fluids in such reservoirs.

  4. Encapsulated microsensors for reservoir interrogation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  5. Reservoir management cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  6. Encapsulated microsensors for reservoir interrogation

    Science.gov (United States)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  7. Candidate sites for future hot-dry-rock development in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.; Decker, E.R.

    1982-12-01

    Generalized geologic and other data are tabulated for 24 potential hot dry rock (HDR) sites in the contiguous United States. The data show that HDR resources occur in many geologic and tectonic settings. Potential reservoir rocks at each prospect are described and each system is cateogrized accoridng to inferred heat sources. The Fenton Hill area in New Mexico is discussed in detail because this region may be considered ideal for HDR development. Three other prospectively valuable localities are described: The Geysers-Clear lake region in California, the Roosevelt Hot Springs area in Utah, and the White Mountains region in New Hampshire. These areas are singled out to illustrate the roles of significantly different geology and geophysics, reservoir rocks, and reservoir heat contents in possible HDR developments.

  8. The mechanics of shallow magma reservoir outgassing

    Science.gov (United States)

    Parmigiani, A.; Degruyter, W.; Leclaire, S.; Huber, C.; Bachmann, O.

    2017-08-01

    Magma degassing fundamentally controls the Earth's volatile cycles. The large amount of gas expelled into the atmosphere during volcanic eruptions (i.e., volcanic outgassing) is the most obvious display of magmatic volatile release. However, owing to the large intrusive:extrusive ratio, and considering the paucity of volatiles left in intrusive rocks after final solidification, volcanic outgassing likely constitutes only a small fraction of the overall mass of magmatic volatiles released to the Earth's surface. Therefore, as most magmas stall on their way to the surface, outgassing of uneruptible, crystal-rich magma storage regions will play a dominant role in closing the balance of volatile element cycling between the mantle and the surface. We use a numerical approach to study the migration of a magmatic volatile phase (MVP) in crystal-rich magma bodies ("mush zones") at the pore scale. Our results suggest that buoyancy-driven outgassing is efficient over crystal volume fractions between 0.4 and 0.7 (for mm-sized crystals). We parameterize our pore-scale results for MVP migration in a thermomechanical magma reservoir model to study outgassing under dynamical conditions where cooling controls the evolution of the proportion of crystal, gas, and melt phases and to investigate the role of the reservoir size and the temperature-dependent viscoelastic response of the crust on outgassing efficiency. We find that buoyancy-driven outgassing allows for a maximum of 40-50% volatiles to leave the reservoir over the 0.4-0.7 crystal volume fractions, implying that a significant amount of outgassing must occur at high crystal content (>0.7) through veining and/or capillary fracturing.

  9. Seventeenth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Miller, F.G.; Horne, R.N.; Brigham, W.E.; Cook, J.W. (Stanford Geothermal Program)

    1992-01-31

    PREFACE The Seventeenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 29-31, 1992. There were one hundred sixteen registered participants which equaled the attendance last year. Participants were from seven foreign countries: Italy, Japan, United Kingdom, France, Belgium, Mexico and New Zealand. Performance of many geothermal fields outside the United States was described in the papers. The Workshop Banquet Speaker was Dr. Raffaele Cataldi. Dr. Cataldi gave a talk on the highlights of his geothermal career. The Stanford Geothermal Program Reservoir Engineering Award for Excellence in Development of Geothermal Energy was awarded to Dr. Cataldi. Dr. Frank Miller presented the award at the banquet. Thirty-eight papers were presented at the Workshop with two papers submitted for publication only. Dr. Roland Horne opened the meeting and the key note speaker was J.E. ''Ted'' Mock who discussed the DOE Geothermal R. & D. Program. The talk focused on aiding long-term, cost effective private resource development. Technical papers were organized in twelve sessions concerning: geochemistry, hot dry rock, injection, geysers, modeling, and reservoir mechanics. Session chairmen were major contributors to the program and we thank: Sabodh Garg., Jim Lovekin, Jim Combs, Ben Barker, Marcel Lippmann, Glenn Horton, Steve Enedy, and John Counsil. The Workshop was organized by the Stanford Geothermal Program faculty, staff, and graduate students. We wish to thank Pat Ota, Ted Sumida, and Terri A. Ramey who also produces the Proceedings Volumes for publication. We owe a great deal of thanks to our students who operate audiovisual equipment and to Francois Groff who coordinated the meeting arrangements for the Workshop. Henry J. Ramey, Jr. Roland N. Horne Frank G. Miller Paul Kruger William E. Brigham Jean W. Cook -vii

  10. Reservoir Operation to Minimize Sedimentation

    Directory of Open Access Journals (Sweden)

    Dyah Ari Wulandari

    2013-10-01

    Full Text Available The Wonogiri Reservoir capacity decreases rapidly, caused by serious sedimentation problems. In 2007, JICA was proposed a sediment storage reservoir with a new spillway for the purpose of sediment flushing / sluicing from The Keduang River. Due to the change of reservoir storage and change of reservoir system, it requires a sustainable reservoir operation technique. This technique is aimed to minimize the deviation between the input and output of sediments. The main objective of this study is to explore the optimal Wonogiri reservoir operation by minimizing the sediment trap. The CSUDP incremental dynamic programming procedure is used for the model optimization.  This new operating rules will also simulate a five years operation period, to show the effect of the implemented techniques. The result of the study are the newly developed reservoir operation system has many advantages when compared to the actual operation system and the disadvantage of this developed system is that the use is mainly designed for a wet hydrologic year, since its performance for the water supply is lower than the actual reservoir operations.Doi: 10.12777/ijse.6.1.16-23 [How to cite this article:  Wulandari, D.A., Legono, D., and Darsono, S., 2014. Reservoir Operation to Minimize Sedimentation. International Journal of Science and Engineering, 5(2,61-65. Doi: 10.12777/ijse.6.1.16-23] Normal 0 false false false EN-US X-NONE X-NONE

  11. All-optical reservoir computing.

    Science.gov (United States)

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  12. Reservoir geochemistry; Geoquimica de reservatorios

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Joelma Pimentel; Rangel, Mario Duncan; Morais, Erica Tavares de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)], Emails: joelma.lopes@petrobras.com.br, mduncan@petrobras.com.br, ericat@petrobras.com.br; Aguiar, Helen G.M. de [Fundacao GORCEIX, Ouro Preto, MG (Brazil)], E-mail: helenaguiar.GORCEIX@petrobras.com.br

    2008-03-15

    Reservoir Geochemistry has many important practical applications during petroleum exploration, appraisal and development of oil fields. The most important uses are related to providing or disproving connectivity between reservoirs of a particular well or horizon. During exploration, reservoir geochemistry can indicate the direction of oil filling, suggesting the most appropriate places for drilling new wells. During production, studies of variations in composition with time and determination of proportions of commingled production from multiple zones, may also be carried out. The chemical constituents of petroleum in natural reservoirs frequently show measurable compositional variations, laterally and vertically. Due to the physical and chemical nature of petroleum changes with increasing maturity (or contribution of a second source during the filling process), lateral and vertical compositional variations exist in petroleum columns as reservoir filling is complete. Compositional variation can also be introduced by biodegradation or water washing. Once the reservoir is filled, density driven mixing and molecular diffusion tend to eliminate inherited compositional variations in an attempt to establish mechanical and chemical equilibrium in the petroleum column (England, 1990). Based on organic geochemical analysis it is possible to define these compositional variations among reservoirs, and use these data for developing of petroleum fields and for reservoir appraisal. Reservoir geochemistry offers rapid and low cost evaluation tools to aid in understanding development and production problems. Moreover, the applied methodology is relatively simple and gives reliable results, and can be performed routinely in any good geochemical laboratory at a relatively low cost. (author)

  13. Microbial Life in an Underground Gas Storage Reservoir

    Science.gov (United States)

    Bombach, Petra; van Almsick, Tobias; Richnow, Hans H.; Zenner, Matthias; Krüger, Martin

    2015-04-01

    While underground gas storage is technically well established for decades, the presence and activity of microorganisms in underground gas reservoirs have still hardly been explored today. Microbial life in underground gas reservoirs is controlled by moderate to high temperatures, elevated pressures, the availability of essential inorganic nutrients, and the availability of appropriate chemical energy sources. Microbial activity may affect the geochemical conditions and the gas composition in an underground reservoir by selective removal of anorganic and organic components from the stored gas and the formation water as well as by generation of metabolic products. From an economic point of view, microbial activities can lead to a loss of stored gas accompanied by a pressure decline in the reservoir, damage of technical equipment by biocorrosion, clogging processes through precipitates and biomass accumulation, and reservoir souring due to a deterioration of the gas quality. We present here results from molecular and cultivation-based methods to characterize microbial communities inhabiting a porous rock gas storage reservoir located in Southern Germany. Four reservoir water samples were obtained from three different geological horizons characterized by an ambient reservoir temperature of about 45 °C and an ambient reservoir pressure of about 92 bar at the time of sampling. A complementary water sample was taken at a water production well completed in a respective horizon but located outside the gas storage reservoir. Microbial community analysis by Illumina Sequencing of bacterial and archaeal 16S rRNA genes indicated the presence of phylogenetically diverse microbial communities of high compositional heterogeneity. In three out of four samples originating from the reservoir, the majority of bacterial sequences affiliated with members of the genera Eubacterium, Acetobacterium and Sporobacterium within Clostridiales, known for their fermenting capabilities. In

  14. Geomechanically Coupled Simulation of Flow in Fractured Reservoirs

    Science.gov (United States)

    Barton, C.; Moos, D.; Hartley, L.; Baxter, S.; Foulquier, L.; Holl, H.; Hogarth, R.

    2012-12-01

    Capturing the necessary and sufficient detail of reservoir hydraulics to accurately evaluate reservoir behavior remains a significant challenge to the exploitation and management of fracture-dominated geothermal reservoirs. In these low matrix permeability reservoirs, stimulation response is controlled largely by the properties of natural and induced fracture networks, which are in turn controlled by the in situ stresses, the fracture distribution and connectivity and the hydraulic behavior of the fractures. This complex interaction of fracture flow systems with the present-day stress field compounds the problem of developing an effective and efficient simulation to characterize, model and predict fractured reservoir performance. We discuss here a case study of the integration of geological, geophysical, geomechanical, and reservoir engineering data to characterize the in situ stresses, the natural fracture network and the controls on fracture permeability in geothermal reservoirs. A 3D geomechanical reservoir model includes constraints on stress magnitudes and orientations, and constraints on mechanical rock properties and the fractures themselves. Such a model is essential to understanding reservoir response to stimulation and production in low matrix permeability, fracture-dominated reservoirs. The geomechanical model for this study was developed using petrophysical, drilling, and wellbore image data along with direct well test measurements and was mapped to a 3D structural grid to facilitate coupled simulation of the fractured reservoir. Wellbore image and stimulation test data were used along with microseismic data acquired during the test to determine the reservoir fracture architecture and to provide control points for a realistic inter-connected discrete fracture network. As most fractures are stress-sensitive, their hydraulic conductivities will change with changes in bottomhole flowing and reservoir pressures, causing variations in production profiles

  15. Elastic Properties of Sedimentary Rocks

    Science.gov (United States)

    Melendez Martinez, Jaime

    Sedimentary rocks are an important research topic since such rocks are associated to sources of ground water as well as oil, gas, and mineral reservoirs. In this work, elastic and physical properties of a variety of sedimentary samples that include glacial sediments, carbonates, shales, one evaporite, and one argillite from a variety of locations are investigated. Assuming vertical transverse isotropy, ultrasonic compressional- and shear-waves (at 1 MHz central frequency) were measured as a function of confining pressure on all samples with the exception of glacial samples which were tested assuming isotropy. Tensile strength tests (Brazilian test) were also carried out on selected glacial samples and, in addition, static-train measurements were conducted on shales and argillite samples. Lithological and textural features of samples were obtained through thin section techniques, scanning electron microscopy images and micro-tomography images. X-ray diffraction and X-Ray fluorescence provided the mineralogical oxides content information. Porosity, density, and pore structure were studied by using a mercury intrusion porosimeter and a helium pycnometer. The wide range of porosities of the studied samples (ranging from a minimum of 1% for shales to a maximum 45% for some glacial sediments) influence the measured velocities since high porosity sample shows an noticeable velocity increment as confining pressure increases as a consequence of closure of microcracks and pores, unlike low porosity samples where increment is quasi-lineal. Implementation of Gassmann's relation to ultrasonic velocities obtained from glacial samples has negligible impact on them when assuming water saturated samples, which suggests that state of saturation it is no so important in defining such velocities and instead they are mainly frame-controlled. On the other hand, velocities measured on carbonate and evaporite samples show that samples are at best weak anisotropic, thus the intrinsic

  16. Seismic response to natural gas anomalies in crystalline rocks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    According to the geological and seismic reflection data of the Chinese Continental Scientific Drilling (CCSD) main-hole (MH), and the anomalies of CH4, CO2, and He are correlated to the three-component seismic reflectors, especially in horizontal component profiles. However, the seismic response is dif-ficult to be explained as the porosity of crystalline rocks is only about 1% in well section where the gas anomalies occur. Seismic velocity measurement of the MH cores indicated that compared with wa-ter-saturated rock samples, seismic velocity (especially the S-wave) could be distinctly decreased by gas contained in tiny cracks despite of the low porosity, and then notable seismic response could be induced in gas-filled crystalline rocks. It could be predicated that if the porosity of certain rocks in the middle crust rose due to water-rock interaction and had natural gas filled, then there would be more probability for natural gas in top of the mid-crust to fill in the crystalline rocks with increased porosity. In such case, based on the decrease of Swave velocity in crystalline rocks, seismic method could be applied in the future to explore natural gas reservoirs in the middle crust.

  17. Seismic response to natural gas anomalies in crystalline rocks

    Institute of Scientific and Technical Information of China (English)

    YANG WenCai; JIN ZhenMin; YU ChangQing

    2008-01-01

    According to the geological and seismic reflection data of the Chinese Continental Scientific Drilling (CCSD) main-hole (MH), and the anomalies of CH4, CO2, and He are correlated to the three-component seismic reflectors, especially in horizontal component profiles. However, the seismic response is difficult to be explained as the porosity of crystalline rocks is only about 1% in well section where the gas anomalies occur. Seismic velocity measurement of the MH cores indicated that compared with water-saturated rock samples, seismic velocity (especially the S-wave) could be distinctly decreased by gas contained in tiny cracks despite of the low porosity, and then notable seismic response could be induced in gas-filled crystalline rocks. It could be predicated that if the porosity of certain rocks in the middle crust rose due to water-rock interaction and had natural gas filled, then there would be more probability for natural gas in top of the mid-crust to fill in the crystalline rocks with increased porosity. In such case, based on the decrease of S-wave velocity in crystalline rocks, seismic method could be applied in the future to explore natural gas reservoirs in the middle crust.

  18. Stratigraphy and reservoir quality of the turbidite deposits, western sag, Bohai bay, China P.R.

    Science.gov (United States)

    Rotimi, Oluwatosin J.; Ako, Bankole D.; Zhenli, Wang

    2014-11-01

    Stratigraphic and subtle reservoirs such as pinchouts, sand lenses and unconformities have been discovered in Bohai basin. These reservoirs occur in sub-basins and sag structures called depressions. A prolific depression is the Liaohe depression that has been filled with rapidly changing mixed alluvial fan deposit of the Cenozoic age. Attempts made at recovering residual hydrocarbon from the subtle reservoir have necessitated the re-evaluation of available data to characterize and model the prolific Shahejie Formation turbidite deposit occurring as pinchouts and sand lenses for hydrocarbon assessment, reservoir quality and possible recovery through enhanced methods. Methods employed covered well logs analysis, clustering analysis for electrofacies and fuzzy logic analysis to predict missing log sections. Stratigraphic and structural analysis was done on SEGY 3D seismic volume after seismic to well tie. Stochastic simulation was done on both discrete and continuous upscaled data. This made it possible to correctly locate and laterally track identified reservoir formation on seismic data. Petrophysical parameters such as porosity and permeability were modeled with result of clustering analysis. Result shows that electrofacies converged on 2 rock classes. The area is characterized by the presence of interbeded sand-shale blanket formations serving as reservoir and seal bodies. The reservoir quality of the formations as seen on the petrophysical analysis done is replicated in simulation volume results. Reservoir rocks have porosity between 0.1 and 0.25, permeability between 1 and 2mD and hydrocarbon saturation as high as 89%. Lithofacies are observed to be laterally inconsistent, sub-parallel to dipping and occurring as porous and permeable continuous beds or pinchouts hosting hydrocarbon. The stochastic stratigraphic model depicts rock units in associations that are synsedimentary. The prevalent configuration gotten from the model gave an insight into exploring and

  19. Seismic wave propagation modeling in porous media for various frequencies: A case study in carbonate rock

    Science.gov (United States)

    Nurhandoko, Bagus Endar B.; Wardaya, Pongga Dikdya; Adler, John; Siahaan, Kisko R.

    2012-06-01

    Seismic wave parameter plays very important role to characterize reservoir properties whereas pore parameter is one of the most important parameter of reservoir. Therefore, wave propagation phenomena in pore media is important to be studied. By referring this study, in-direct pore measurement method based on seismic wave propagation can be developed. Porosity play important role in reservoir, because the porosity can be as compartment of fluid. Many type of porosity like primary as well as secondary porosity. Carbonate rock consist many type of porosity, i.e.: inter granular porosity, moldic porosity and also fracture porosity. The complexity of pore type in carbonate rocks make the wave propagation in these rocks is more complex than sand reservoir. We have studied numerically wave propagation in carbonate rock by finite difference modeling in time-space domain. The medium of wave propagation was modeled by base on the result of pattern recognition using artificial neural network. The image of thin slice of carbonate rock is then translated into the velocity matrix. Each mineral contents including pore of thin slice image are translated to velocity since mineral has unique velocity. After matrix velocity model has been developed, the seismic wave is propagated numerically in this model. The phenomena diffraction is clearly shown while wave propagates in this complex carbonate medium. The seismic wave is modeled in various frequencies. The result shows dispersive phenomena where high frequency wave tends to propagate in matrix instead pores. In the other hand, the low frequency waves tend to propagate through pore space even though the velocity of pore is very low. Therefore, this dispersive phenomena of seismic wave propagation can be the future indirect measurement technology for predicting the existence or intensity of pore space in reservoir rock. It will be very useful for the future reservoir characterization.

  20. An asixymmetric diffusion experiment for the determination of diffusion and sorption coefficients of rock samples

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, M.; Hiratsuka, T.; Ito, K.; Finsterle, S.

    2011-02-01

    Diffusion anisotropy is a critical property in predicting migration of substances in sedimentary formations with very low permeability. The diffusion anisotropy of sedimentary rocks has been evaluated mainly from laboratory diffusion experiments, in which the directional diffusivities are separately estimated by through-diffusion experiments using different rock samples, or concurrently by in-diffusion experiments in which only the tracer profile in a rock block is measured. To estimate the diffusion anisotropy from a single rock sample, this study proposes an axisymmetric diffusion test, in which tracer diffuses between a cylindrical rock sample and a surrounding solution reservoir. The tracer diffusion between the sample and reservoir can be monitored from the reservoir tracer concentrations, and the tracer profile could also be obtained after dismantling the sample. Semi-analytical solutions are derived for tracer concentrations in both the reservoir and sample, accounting for an anisotropic diffusion tensor of rank two as well as the dilution effects from sampling and replacement of reservoir solution. The transient and steady-state analyses were examined experimentally and numerically for different experimental configurations, but without the need for tracer profiling. These experimental configurations are tested for in- and out-diffusion experiments using Koetoi and Wakkanai mudstones and Shirahama sandstone, and are scrutinized by a numerical approach to identify favorable conditions for parameter estimation. The analysis reveals the difficulty in estimating diffusion anisotropy; test configurations are proposed for enhanced identifiability of diffusion anisotropy. Moreover, it is demonstrated that the axisymmetric diffusion test is efficient in obtaining the sorption parameter from both steady-state and transient data, and in determining the effective diffusion coefficient if isotropic diffusion is assumed. Moreover, measuring reservoir concentrations in an

  1. CRITERIA FOR ROCK ENGINEERING FAILURE

    Institute of Scientific and Technical Information of China (English)

    ZHUDeren; ZHANGYuzhuo

    1995-01-01

    A great number of underground rock projects are maintained in the rock mass which is subject to rock damage and failure development. In many cases, the rock. engineering is still under normal working conditions even though rock is already fails to some extent. This paper introduces two different concepts: rock failure and rock engineering failure. Rock failure is defined as a mechanical state under which an applicable characteristic is changed or lost.However, the rock engineering failure is an engineering state under which an applicable function is changed or lost. The failure of surrounding rocks is the major reason of rock engineering failure. The criterion of rock engineering failure depends on the limit of applicable functions. The rock engineering failure state possesses a corresponding point in rock failure state. In this paper, a description of rock engineering failure criterion is given by simply using a mechanical equation or expression. It is expected that the study of rock engineering failure criterion will be an optimal approach that combines research of rock mechanics with rock engineering problems.

  2. Integrated petrographical and petrophysical studies of some Eocene carbonate rocks, Southwest Sinai, Egypt

    Directory of Open Access Journals (Sweden)

    Hesham Abuseda

    2015-06-01

    The petrophysical behavior of the studied facies has been outlined by measuring rock porosity, density, permeability, and electrical resistivity. The reservoir quality index (RQI reveals that, the petrophysical features of the studied facies are consistent with the petrographical characteristics indicating bad reservoir properties for Thebes, Samalut, Darat and Tanka formations in the nearby subsurface extensions. Studying the petrophysical behavior indicates that, both permeability and formation resistivity factor are mostly dependent on the effective porosity and to some extent on the electric tortuosity.

  3. Asphalt features and gas accumulation mechanism of Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Wei Li

    2015-10-01

    Full Text Available Breakthroughs have been made in natural gas exploration in Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin, recently. However, there are disputes with regard to the genetic mechanisms of natural gas reservoirs. The development law of asphalts in the Sinian reservoirs may play an extremely important role in the study of the relationships between palaeo oil and gas reservoirs. Accordingly, researches were conducted on the features and development patterns of asphalts in the Sinian reservoirs in this area. The following research results were obtained. (1 Asphalts in the Sinian reservoirs were developed after the important hydrothermal event in the Sichuan Basin, namely the well-known Emei Taphrogeny in the mid-late Permian Period. (2 Distribution of asphalts is related to palaeo oil reservoirs under the control of palaeo-structures of Indosinian-Yanshanian Period, when the palaeo-structures contained high content of asphalts in the high positions of the palaeo-uplift. (3 Large-scale oil and gas accumulations in the Sinian reservoirs occurred in the Indosinian-Yanshanian Period to generate the Leshan-Ziyang and Gaoshiti-Moxi-Guang'an palaeo oil reservoirs. Cracking of crude oil in the major parts of these palaeo oil reservoirs controlled the development of the present natural gas reservoirs. (4 The development of asphalts in the Sinian reservoirs indicates that hydrocarbons in the Dengying Formation originated from Cambrian source rocks and natural gas accumulated in the Sinian reservoirs are products of late-stage cracking of the Sinian reservoirs. (5 The Sinian palaeo-structures of Indosinian-Yanshanian Period in the Sichuan Basin are favorable regions for the development of the Sinian reservoirs, where discoveries and exploration practices will play an important role in the era of Sinian natural gas development in China.

  4. Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Michael Batzle

    2006-04-30

    During this last period of the ''Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs'' project (Grant/Cooperative Agreement DE-FC26-02NT15342), we finalized integration of rock physics, well log analysis, seismic processing, and forward modeling techniques. Most of the last quarter was spent combining the results from the principal investigators and come to some final conclusions about the project. Also much of the effort was directed towards technology transfer through the Direct Hydrocarbon Indicators mini-symposium at UH and through publications. As a result we have: (1) Tested a new method to directly invert reservoir properties, water saturation, Sw, and porosity from seismic AVO attributes; (2) Constrained the seismic response based on fluid and rock property correlations; (3) Reprocessed seismic data from Ursa field; (4) Compared thin layer property distributions and averaging on AVO response; (5) Related pressures and sorting effects on porosity and their influence on DHI's; (6) Examined and compared gas saturation effects for deep and shallow reservoirs; (7) Performed forward modeling using geobodies from deepwater outcrops; (8) Documented velocities for deepwater sediments; (9) Continued incorporating outcrop descriptive models in seismic forward models; (10) Held an open DHI symposium to present the final results of the project; (11) Relations between Sw, porosity, and AVO attributes; (12) Models of Complex, Layered Reservoirs; and (14) Technology transfer Several factors can contribute to limit our ability to extract accurate hydrocarbon saturations in deep water environments. Rock and fluid properties are one factor, since, for example, hydrocarbon properties will be considerably different with great depths (high pressure) when compared to shallow properties. Significant over pressure, on the other hand will make the rocks behave as if they were shallower. In addition to the physical properties, the scale and

  5. Rock physics for 4D modeling of heavy oil sands in Petromonagas field

    Energy Technology Data Exchange (ETDEWEB)

    Florez-Nino, J.M. [BP America Inc., Houston, TX (United States); Vega, V. [BP Andean, Caracas (Venezuela, Bolivarian Republic of)

    2009-07-01

    Seismic reservoir characterization and monitoring requires a good understanding of the many factors that influence the elastic properties of reservoir rocks, as well as the changes in elastic properties induced by reservoir production, such as those derived from variations in pressure, temperature, or reservoir porosity and saturation. This understanding can be obtained from a both rock physics modeling and direct laboratory measurements. This paper presented a rock physics analysis carried out to integrate well-log and seismic data for reservoir characterization and forward modeling of four-dimensional seismic response in heavy oil sands. The paper also presented an evaluation of the seismic response related to thermal recovery, including an analysis that accounted for frequency-dependant p-wave velocity dispersion; highly viscous fluid; temperature effects on fluid properties; and pressure effects on rock properties. It was concluded that p-wave and shear-wave velocity variation as a function of temperature are the dominant factors to consider while integrating well-log and seismic data in sands of the Morichal members of the Oficina formation in Venezuela. 6 refs., 9 figs.

  6. FUNDAMENTALS OF RESERVOIR SURFACE ENERGY AS RELATED TO SURFACE PROPERTIES, WETTABILITY, CAPILLARY ACTION, AND OIL RECOVERY FROM FRACTURED RESERVOIRS BY SPONTANEOUS IMBIBITION

    Energy Technology Data Exchange (ETDEWEB)

    Norman R. Morrow

    2004-07-01

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  7. Fundamentals of Reservoir Surface Energy as Related to Surface Properties, Wettability, Capillary Action, and Oil Recovery from Fractured Reservoirs by Spontaneous Imbibition

    Energy Technology Data Exchange (ETDEWEB)

    Norman Morrow; Herbert Fischer; Yu Li; Geoffrey Mason; Douglas Ruth; Siddhartha Seth; Zhengxin Tong; Evren Unsal; Siluni Wickramathilaka; Shaochang Wo; Peigui Yin

    2008-06-30

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the non-wetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  8. FUNDAMENTALS OF RESERVOIR SURFACE ENERGY AS RELATED TO SURFACE PROPERTIES, WETTABILITY, CAPILLARY ACTION, AND OIL RECOVERY FROM FRACTURED RESERVOIRS BY SPONTANEOUS IMBIBITION

    Energy Technology Data Exchange (ETDEWEB)

    Norman R. Morrow; Herbert Fischer; Yu Li; Geoffrey Mason; Douglas Ruth; Siddhartha Seth; Peigui Yin; Shaochang Wo

    2005-02-01

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  9. FUNDAMENTALS OF RESERVOIR SURFACE ENERGY AS RELATED TO SURFACE PROPERTIES, WETTABILITY, CAPILLARY ACTION, AND OIL RECOVERY FROM FRACTURED RESERVOIRS BY SPONTANEOUS IMBIBITION

    Energy Technology Data Exchange (ETDEWEB)

    Norman R. Morrow; Herbert Fischer; Yu Li; Geoffrey Mason; Douglas Ruth; Siddhartha Seth; Peigui Yin; Shaochang Wo

    2004-10-01

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  10. FUNDAMENTALS OF RESERVOIR SURFACE ENERGY AS RELATED TO SURFACE PROPERTIES, WETTABILITY, CAPILLARY ACTION, AND OIL RECOVERY FROM FRACTURED RESERVOIRS BY SPONTANEOUS IMBIBITION

    Energy Technology Data Exchange (ETDEWEB)

    Norman R. Morrow; Herbert Fischer; Yu Li; Geoffrey Mason; Douglas Ruth; Siddhartha Seth; Peigui Yin; Shaochang Wo

    2005-04-01

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  11. Fundamentals of reservoir surface energy as related to surface properties, wettability, capillary action, and oil recovery from fractured reservoirs by spontaneous imbibition

    Energy Technology Data Exchange (ETDEWEB)

    Norman R. Morrow; Herbert Fischer; Yu Li; Geoffrey Mason; Douglas Ruth; Siddhartha Seth; Jason Zhengxin Tong; Peigui Yin; Shaochang Wo

    2006-02-01

    The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed

  12. THERMO-HYDRO-MECHANICAL MODELING OF WORKING FLUID INJECTION AND THERMAL ENERGY EXTRACTION IN EGS FRACTURES AND ROCK MATRIX

    Energy Technology Data Exchange (ETDEWEB)

    Robert Podgorney; Chuan Lu; Hai Huang

    2012-01-01

    Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability

  13. Digital Rock Simulation of Flow in Carbonate Samples

    Science.gov (United States)

    Klemin, D.; Andersen, M.

    2014-12-01

    Reservoir engineering has becomes more complex to deal with current challenges, so core analysts must understand and model pore geometries and fluid behaviors at pores scales more rapidly and realistically. We introduce an industry-unique direct hydrodynamic pore flow simulator that operates on pore geometries from digital rock models obtained using microCT or 3D scanning electron microscope (SEM) images. The PVT and rheological models used in the simulator represent real reservoir fluids. Fluid-solid interactions are introduced using distributed micro-scale wetting properties. The simulator uses density functional approach applied for hydrodynamics of complex systems. This talk covers selected applications of the simulator. We performed microCT scanning of six different carbonate rock samples from homogeneous limestones to vuggy carbonates. From these, we constructed digital rock models representing pore geometries for the simulator. We simulated nonreactive tracer flow in all six digital models using a digital fluid description that included a passive tracer solution. During the simulation, we evaluated the composition of the effluent. Results of tracer flow simulations corresponded well with experimental data of nonreactive tracer floods for the same carbonate rock types. This simulation data of the non-reactive tracer flow can be used to calculate the volume of the rock accessible by the fluid, which can be further used to predict response of a porous medium to a reactive fluid. The described digital core analysis workflow provides a basis for a wide variety of activities, including input to design acidizing jobs and evaluating treatment efficiency and EOR economics. Digital rock multiphase flow simulations of a scanned carbonate rock evaluated the effect of wettability on flow properties. Various wetting properties were tested: slightly oil wet, slightly water wet, and water wet. Steady-state relative permeability simulations yielded curves for all three

  14. Seismic-Scale Rock Physics of Methane Hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Amos Nur

    2009-01-08

    We quantify natural methane hydrate reservoirs by generating synthetic seismic traces and comparing them to real seismic data: if the synthetic matches the observed data, then the reservoir properties and conditions used in synthetic modeling might be the same as the actual, in-situ reservoir conditions. This approach is model-based: it uses rock physics equations that link the porosity and mineralogy of the host sediment, pressure, and hydrate saturation, and the resulting elastic-wave velocity and density. One result of such seismic forward modeling is a catalogue of seismic reflections of methane hydrate which can serve as a field guide to hydrate identification from real seismic data. We verify this approach using field data from known hydrate deposits.

  15. Analysis and evaluation of interwell seismic logging techniques for hydrocarbon reservoir characterization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Parra, J.O.; Zook, B.J.; Sturdivant, V.R.

    1994-06-01

    The work reported herein represents the third year work in evaluating high-resolution interwell seismic logging techniques for hydrocarbon reservoir characterization. The objective of this project is to investigate interwell seismic logging techniques for indirectly interpreting oil and gas reservoir geology and rock physical properties. The work involves a balanced study of theoretical and numerical modeling of seismic waves transmitted between pairs of wells combined with experimental data acquisition and processing at controlled field conditions. The field applications of this reservoir probing concept are aimed at demonstrating high resolution measurements and detailed interpretation of heterogeneous hydrocarbon-bearing formations. The first part of this third year project efforts was devoted to thoroughly evaluating interwell seismic logging and reverse VSP in a hydrocarbon-bearing formation at the Buckhorn test site in Illinois. Specifically, the data from the experiments conducted in the second year of this project were analyzed to delineate geological structures and to extract rock physical parameters. The second part of this project is devoted to the evaluation of continuity logging techniques for hydrocarbon reservoir continuity. Specifically, this part of the project includes the evaluation of methods of measurements, modeling and data processing to delineate the reservoir architecture and relate dispersion and attenuation measurements to rock physical properties.

  16. MeProRisk - a Joint Venture for Minimizing Risk in Geothermal Reservoir Development

    Science.gov (United States)

    Clauser, C.; Marquart, G.

    2009-12-01

    Exploration and development of geothermal reservoirs for the generation of electric energy involves high engineering and economic risks due to the need for 3-D geophysical surface surveys and deep boreholes. The MeProRisk project provides a strategy guideline for reducing these risks by combining cross-disciplinary information from different specialists: Scientists from three German universities and two private companies contribute with new methods in seismic modeling and interpretation, numerical reservoir simulation, estimation of petrophysical parameters, and 3-D visualization. The approach chosen in MeProRisk consists in considering prospecting and developing of geothermal reservoirs as an iterative process. A first conceptual model for fluid flow and heat transport simulation can be developed based on limited available initial information on geology and rock properties. In the next step, additional data is incorporated which is based on (a) new seismic interpretation methods designed for delineating fracture systems, (b) statistical studies on large numbers of rock samples for estimating reliable rock parameters, (c) in situ estimates of the hydraulic conductivity tensor. This results in a continuous refinement of the reservoir model where inverse modelling of fluid flow and heat transport allows infering the uncertainty and resolution of the model at each iteration step. This finally yields a calibrated reservoir model which may be used to direct further exploration by optimizing additional borehole locations, estimate the uncertainty of key operational and economic parameters, and optimize the long-term operation of a geothermal resrvoir.

  17. Penerapan Dinamika Fluida dalam Perhitungan Kecepatan Aliran dan Perolehan Minyak di Reservoir

    Directory of Open Access Journals (Sweden)

    Dwi Listriana Kusumastuti

    2014-12-01

    Full Text Available Water, oil and gas inside the earth are stored in the pores of the reservoir rock. In the world of petroleum industry, calculation of volume of the oil that can be recovered from the reservoir is something important to do. This calculation involves the calculation of the velocity of fluid flow by utilizing the principles and formulas provided by the Fluid Dynamics. The formula is usually applied to the fluid flow passing through a well defined control volume, for example: cylinder, curved pipe, straight pipes with different diameters at the input and output, and so forth. However, because of reservoir rock, as the fluid flow medium, has a wide variety of possible forms of the control volumes, hence, calculation of the velocity of the fluid flow is becoming difficult as it would involve calculations of fluid flow velocity for each control volume. This difficulties is mainly caused by the fact that these control volumes, that existed in the rock, cannot be well defined. This paper will describe a method for calculating this fluid flow velocity of the control volume, which consists of a combination of laboratory measurements and the use of some theories in the Fluid Dynamics. This method has been proofed can be used for calculating fluid flow velocity as well as oil recovery in reservoir rocks, with fairly good accuration.

  18. An adaptive nonlinear solution scheme for reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lett, G.S. [Scientific Software - Intercomp, Inc., Denver, CO (United States)

    1996-12-31

    Numerical reservoir simulation involves solving large, nonlinear systems of PDE with strongly discontinuous coefficients. Because of the large demands on computer memory and CPU, most users must perform simulations on very coarse grids. The average properties of the fluids and rocks must be estimated on these grids. These coarse grid {open_quotes}effective{close_quotes} properties are costly to determine, and risky to use, since their optimal values depend on the fluid flow being simulated. Thus, they must be found by trial-and-error techniques, and the more coarse the grid, the poorer the results. This paper describes a numerical reservoir simulator which accepts fine scale properties and automatically generates multiple levels of coarse grid rock and fluid properties. The fine grid properties and the coarse grid simulation results are used to estimate discretization errors with multilevel error expansions. These expansions are local, and identify areas requiring local grid refinement. These refinements are added adoptively by the simulator, and the resulting composite grid equations are solved by a nonlinear Fast Adaptive Composite (FAC) Grid method, with a damped Newton algorithm being used on each local grid. The nonsymmetric linear system of equations resulting from Newton`s method are in turn solved by a preconditioned Conjugate Gradients-like algorithm. The scheme is demonstrated by performing fine and coarse grid simulations of several multiphase reservoirs from around the world.

  19. Days of Rock

    Institute of Scientific and Technical Information of China (English)

    YUAN

    2004-01-01

    FROM last October 1 st to 3rd, at the foot of Fragrant Hill, a suburban Beijing resort famous for its flaming maple leaves in autumn, more than 20,000 rock fans indulged themselves in music for three days.

  20. Writing Rock Music Reviews.

    Science.gov (United States)

    Brown, Donal

    1980-01-01

    Suggests ways student reviewers of rock music groups can write better reviews. Among the suggestions made are that reviewers occasionally discuss the audience or what makes a particular group unique, support general comment with detail, and avoid ecstatic adjectives. (TJ)

  1. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  2. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed totake the breath away from visitors. The areahas another major attraction, though: the Helan Mountain rock engravings.

  3. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  4. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  5. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  6. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    HU YUE

    2010-01-01

    @@ With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed to take the breath away from visitors. The area has another major attraction, though: the Helan Mountain rock engravings.

  7. Reservoir sedimentation; a literature survey

    NARCIS (Netherlands)

    Sloff, C.J.

    1991-01-01

    A survey of literature is made on reservoir sedimentation, one of the most threatening processes for world-wide reservoir performance. The sedimentation processes, their impacts, and their controlling factors are assessed from a hydraulic engineering point of view with special emphasis on mathematic

  8. Reservoir sedimentation; a literature survey

    NARCIS (Netherlands)

    Sloff, C.J.

    1991-01-01

    A survey of literature is made on reservoir sedimentation, one of the most threatening processes for world-wide reservoir performance. The sedimentation processes, their impacts, and their controlling factors are assessed from a hydraulic engineering point of view with special emphasis on mathematic

  9. An improved reservoir oxide cathode

    Science.gov (United States)

    Wang, Xiaoxia; Liao, Xianheng; Luo, Jirun; Zhao, Qinglan

    2005-09-01

    A new type of reservoir oxide cathode has been developed in IECAS. The emission characteristics of the cathode are tested. The results show the new cathode has higher emission current density and better resistance to poisoning at same operating condition compared with those of conventional reservoir oxide cathode.

  10. Reservoir sedimentation; a literature survey

    NARCIS (Netherlands)

    Sloff, C.J.

    1991-01-01

    A survey of literature is made on reservoir sedimentation, one of the most threatening processes for world-wide reservoir performance. The sedimentation processes, their impacts, and their controlling factors are assessed from a hydraulic engineering point of view with special emphasis on

  11. Impact of hydraulic perforation on fracture initiation and propagation in shale rocks

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xi; JU Yang; YANG Yong; SU Sun; GONG WenBo

    2016-01-01

    To enhance the oil and gas recovery rate,hydraulic fracturing techniques have been widely adopted for stimulation of low-permeability reservoirs.Pioneering work indicates that hydraulic perforation and layout could significantly affect fracture initiation and propagation in low-permeability reservoir rocks subjected to complex in-situ stresses.This paper reports on a novel numerical method that incorporates fracture mechanics principles and the numerical tools FRANC3D and ANSYS to investigate the three-dimensional initiation and propagation behavior of hydro-fracturing cracks in shale rock.Considering the transverse isotropic property of shale rocks,the mechanical parameters of reservoir rocks attained from laboratory tests were adopted in the simulation.The influence of perforation layouts on the 3D initiation of hydro-fracturing fractures in reservoir rocks under geo-stresses was quantitatively illuminated.The propagation and growth of fractures in three dimensions in different perforating azimuth values were illustrated.The results indicate that:1) the optimal perforation direction should be parallel to the maximum horizontal principal stress,2) the crack plane gradually turns toward the direction of the maximum horizontal principal stress when they are not in parallel,3) compared with the linear and symmetric pattern,the staggered perforation is the optimal one,4) the proper perforation density is four to six holes per meter,5) the optimal perforation diameter in this model is 30 mm,and 6) the influence of the perforation depth on the fracture initiation pressure is low.

  12. Rock avalanches on glaciers

    OpenAIRE

    Shugar, Daniel

    2011-01-01

    This thesis examines relations between rock avalanches and the glaciers on which they are deposited. I have attempted to understand a geophysical phenomenon from two viewpoints: sedimentology and glaciology. The contributions are both methodological, and practical. I have used a GIS to quantify debris sheet geomorphology. A thorough characterization of rock avalanche debris is a necessary step in understanding the flow mechanics of large landslide. I have also developed a technique for solvin...

  13. Evolution of sedimentary rock formation of a rock association level

    Science.gov (United States)

    Kuznetsov, V. G.

    2017-07-01

    The evolution of sedimentary rock formation of a highly organized level (paragenetic rock associations) is more complex than that of a poorly organized level (rocks). Subjacent rock associations are established for the entire geological evolution of the Earth: they varied in time and were obsolescent or, in contrast, nascent and momentary. A certain cyclicity of evolution is identified along with directed changes.

  14. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    , and the best reservoir properties are typically found in mudstone intervals. Chalk mudstones vary a lot though. The best mudstones are purely calcitic, well sorted and may have been redeposited by traction currents. Other mudstones are rich in very fine grained silica, which takes up pore space and thus...... stabilizes chemically by recrystallization. This process requires energy and is promoted by temperature. This recrystallization in principle does not influence porosity, but only specific surface, which decreases during recrystallization, causing permeability to increase. The central North Sea is a warm...... intervals are to some extent cemented and cannot compact mechanically at realistic effective stresses and only deform elastically. All chalk intervals though, may react by fracturing to changes in shear stress. So where natural fractures are not prevalent, fractures may be generated hydraulically. Fractures...

  15. Reasons for reservoir effect variability

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    Freshwater reservoir effects can be large and highly variable. I will present my investigations into the short-term variability of the freshwater reservoir effect in two Northern German rivers. The samples analysed in this study were collected between 2007 and 2012. Reservoir ages of water samples......, aquatic plants and fish from the rivers Alster and Trave range between zero and about 3,000 radiocarbon years. The reservoir age of water DIC depends to a large extent on the origin of the water and is for example correlated with precipitation amounts. These short-term variations are smoothed out in water...... plants. Their carbon should represent an average value of the entire growth season. However, there are large reservoir age variations in aquatic plants and animals as well. These can best be explained by the multitude of carbon sources which can be utilized by aquatic organisms, and which have...

  16. Weathering of rock 'Ginger'

    Science.gov (United States)

    1997-01-01

    One of the more unusual rocks at the site is Ginger, located southeast of the lander. Parts of it have the reddest color of any material in view, whereas its rounded lobes are gray and relatively unweathered. These color differences are brought out in the inset, enhanced at the upper right. In the false color image at the lower right, the shape of the visible-wavelength spectrum (related to the abundance of weathered ferric iron minerals) is indicated by the hue of the rocks. Blue indicates relatively unweathered rocks. Typical soils and drift, which are heavily weathered, are shown in green and flesh tones. The very red color in the creases in the rock surface correspond to a crust of ferric minerals. The origin of the rock is uncertain; the ferric crust may have grown underneath the rock, or it may cement pebbles together into a conglomerate. Ginger will be a target of future super-resolution studies to better constrain its origin.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  17. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The

  18. Research on Microscopic Characteristics of Carbonate Reservoir Fracture fillings Based on Microscopic Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Li Jing

    2016-01-01

    Full Text Available The characteristics of hole and seepage of carbonate rocks depend on the structural components of carbonate rocks and the combination relationship with these structural components under multi-scale. The quality of filling in reservoir fracture is an important part of fracture description. In this paper, the method of microscopic infrared spectral imaging was used, and the spectra cubic database was established by means of spectral imaging experiment. Each single band image which characterizes the related substances was extracted and the microcosmic characters of the filling in carbonate reservoirs fracture from Wumishan formation in Renqiu oilfield were studied. The spatial distribution maps of different chemical composition and groups in the core sample were obtained. The distribution of different hydrocarbon in the fracture of the reservoir and the connectivity of the pores etc. were better revealed

  19. Kinetics of hydrocarbon generation for Well Yingnan 2 gas reservoir,Tarim Basin,CHina

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Well Yingnan 2,an important exploratory well in the east of Tarim Basin,yields high commercial oil and gas flow in Jurassic.Natural gas components and carbon isotopic composition indicate that it belongs to sapropel type gas.Because this region presents many suits of hydrocarbon source rocks,there are some controversies that natural gases were generated from kerogen gas or crude oil cracking gas at present.By using the kinetics of hydrocarbon generation and carbon isotope,natural gas of Well Yingnan 2 is composed mainly of crude oil cracking gas,about 72%,it is generated from secondary kerogen gas of Cambrian-Lower Ordovician source rock and crude oil cracking gas of Mid-Upper Ordovician oil reservoir.The main oil and gas filling time is 65 Ma later in the Jurassic gas reservoir of Well Yingnan 2,so the gas reservoir belongs to late accumulation and continuous filling type.

  20. Petrofacies Analysis - A Petrophysical Tool for Geologic/Engineering Reservoir Characterization

    Science.gov (United States)

    Watney, W.L.; Guy, W.J.; Doveton, J.H.; Bhattacharya, S.; Gerlach, P.M.; Bohling, G.C.; Carr, T.R.

    1998-01-01

    Petrofacies analysis is defined as the characterization and classification of pore types and fluid saturations as revealed by petrophysical measurements of a reservoir. The word "petrofacies" makes an explicit link between petroleum engineers' concerns with pore characteristics as arbiters of production performance and the facies paradigm of geologists as a methodology for genetic understanding and prediction. In petrofacies analysis, the porosity and resistivity axes of the classical Pickett plot are used to map water saturation, bulk volume water, and estimated permeability, as well as capillary pressure information where it is available. When data points are connected in order of depth within a reservoir, the characteristic patterns reflect reservoir rock character and its interplay with the hydrocarbon column. A third variable can be presented at each point on the crossplot by assigning a color scale that is based on other well logs, often gamma ray or photoelectric effect, or other derived variables. Contrasts between reservoir pore types and fluid saturations are reflected in changing patterns on the crossplot and can help discriminate and characterize reservoir heterogeneity. Many hundreds of analyses of well logs facilitated by spreadsheet and object-oriented programming have provided the means to distinguish patterns typical of certain complex pore types (size and connectedness) for sandstones and carbonate reservoirs, occurrences of irreducible water saturation, and presence of transition zones. The result has been an improved means to evaluate potential production, such as bypassed pay behind pipe and in old exploration wells, or to assess zonation and continuity of the reservoir. Petrofacies analysis in this study was applied to distinguishing flow units and including discriminating pore type as an assessment of reservoir conformance and continuity. The analysis is facilitated through the use of colorimage cross sections depicting depositional sequences

  1. The Silurian Reservoir Bed-Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 王洪玉; 曾溅辉

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt) in the Silurian asphaltic sandstones of the Tarim Basin. These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir, which were derived from Lower Paleozoic source rocks. Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration. The differen tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed, and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil. There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin. One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the transport layer and unconformity surface. Reservoir bed-differentiated asphalts have two characteristics: total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity. The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  2. The Silurian Reservoir Bed—Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 等

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt)in the Silurian asphaltic sandstones of the Tarim Basin.These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir,which were derived from Lower Paleozoic source rocks.Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration.The different-tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed,and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil.There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin.One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the trans-port layer and unconformity surface.Reservoir bed-differentiated asphalts have two characteris-tics:total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity.The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  3. Characterization of dynamic change of Fan-delta reservoir properties in water-drive development

    Energy Technology Data Exchange (ETDEWEB)

    Wu Shenghe; Xiong Qihua; Liu Yuhong [Univ. of Petroleum Changping, Beijing (China)

    1997-08-01

    Fan-delta reservoir in Huzhuangji oil field of east China, is a typical highly heterogeneous