Tesi: "Sandstone"

1

Gu, Xue Fan 1956. "Shear behaviour of sandstone-concrete joints and pile shafts in sandstone". Monash University, Dept. of Civil Engineering, 2001. http://arrow.monash.edu.au/hdl/1959.1/8856.

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2

Haji, Abdul Karim Roslinah. "Foamed bitumen stabilised sandstone aggregates". Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/29060/.

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Roads form a key element for the expansion of economy and development of a country. As with most countries, Brunei Darussalam has been facing a rapid development to meet the economic growth that requires an efficient road network. Therefore, the scarcity of conventional road aggregates in Brunei Darussalam means that the country has a strong dependence on imported aggregates from overseas to construct quality roads. Further restrictions on local road specifications make it almost impossible to include low quality granular materials. The study reported in this thesis was undertaken on the basis that the dependence on overseas resources is not a viable long- term solution. The research task has been, therefore, to ascertain the quality of local sandstones for road construction and then to propose means to upgrade their performance quality for optimum utilisation in cost effective applications. This study focused on the road base layer since that is where most aggregate is used. The approach used for this study was to identify the common rock in Brunei Darussalam and review the candidate treatment methods. A weighted matrix for these candidate treatment methods was constructed to determine the overall ranking with selected key criteria on the basis of the local climatic condition, construction preferences and traditions. From the reviews, Foamed bitumen was selected as a feasible treatment method that can improve the sandstone characteristics under local conditions. Three curing conditions were adopted in this study, simulating extreme field conditions in Brunei Darussalam, to characterise the mechanical properties of foamed bitumen stabilised sandstone mixtures, termed 'foam mix'. The following tests were conducted: • The response of stiffness modulus behaviour in the foam mix produced at different levels of mixing moisture content and cement content under dry and wet conditions was measured to study the mixing moisture content (MMC) in foam mix design. • A humid curing study was performed to indicate the short term stiffness of foam mixes in order to aid in the prediction of the delay necessary before a road comprising these foam mixes could be opened to traffic, and to determine how curing time and moisture content affect the development of stiffness modulus with and without cement. • A preliminary investigation was carried out into the potential of coir fibres as a reinforcement agent in the foam mix, measuring its effect on stiffness modulus, tensile strength and permanent deformation. • Being sensitive to moisture, the climatic durability of foam mix was further assessed by studying the effect of dry/wet cycles on the stiffness modulus incorporating other additives such as hydrated lime and pre-blended bitumen with wet fix. • Microscopic analysis has been undertaken as a guide to characterise the microstructure of the foam mix incorporating additives such as cement and coir fibres in order to support the laboratory findings. The laboratory results confirmed that the stiffness behaviour of the foam mix could be influenced by the amount of MMC, cement content and humidity of the environment. It was found that the foam mix with 1% cement (by mass of dried aggregates) at MMC, 70% of OMC, produced a durable mixture with a high stiffness modulus value in both dry and wet conditions as well as when subjected to the effect of alternate dry and wet cycles. The investigation on the potential of coir fibre to reinforce the foam mix indicated that the fibre did help to prevent large cracks in the foam mixes but unfortunately the reinforced foam mixes were easily damaged under a wet environment.

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3

De, Ros Luiz Fernando, e Universitatis Upsaliensis Institute of Earth Sciences Mineralogy-Petrology Acta. "Compositional controls on sandstone diagenesis". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1996. http://hdl.handle.net/10183/1498.

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4

Rahman, Syed Hafizur. "Colloid movement through saturated sandstone matrix". Thesis, University of Birmingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434702.

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5

Scott, Julian Barry Tuson. "Low-frequency electrical spectroscopy of sandstone". Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403448.

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6

Wild, E. K. "The sedimentology and reservoir quality of the Kinnerton Sandstone Formation, U.K. and the Tirrawara Sandstone, S. Australia". Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384483.

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7

Dassow, Jessica Maria Irmgard. "Sensing and understanding the resilience of sandstone". Thesis, University of Glasgow, 2019. http://theses.gla.ac.uk/41087/.

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When stones are incorporated into buildings their mineralogical composition and texture alters to adapt to the new environmental conditions. One of the most common building stones in Scotland is sandstone. Due to its high porosity and mineralogical composition sandstones can be prone to weathering. Scotland's diverse stone built heritage is endangered by frequent changes in environmental conditions such as cyclic wetting and drying and temperature changes caused by insolation. Buildings also face increased pressure through climate change. In Scotland, the decay of sandstone is a serious problem that urgently requires new approaches to preserve built heritage and to reduce maintenance costs. It is therefore important to understand the extent and timescales of weathering processes. New approaches to assess stone decay are required for deciding on the best conservation strategy for historic buildings. These approaches or tools need to be minimally or non-invasive, portable and provide a consistent method to gain empirical data for evaluation of the progress of weathering. This project aims to develop two new in-situ techniques that can assess the state of decay of building stones beneath their outer surface. The developed techniques use a laser interferometer to measure dilation over time and an ultrasonic drilling tool to estimate the structural properties of the stones. These measurements are joint with micro-climate monitoring of sandstones to enable a combined assessment of stone decay. The laser interferometer can measure decay induced contraction or expansion of stones on the nanometre scale. Salt crystallisation in porous systems can be examined with very high precision under any temperature and humidity condition that enable salt growth. Characterising dilation events through precise measurement of displacement and its frequency can provide insight on the intensity of decay of the building material. The drying behaviour of different samples (unweathered, weathered and artificially weathered) was monitored to enable the differentiation of rock type and state of decay. The ultrasonic drilling tool allows identification of changes in the structure of a sample while drilling a hole up to 4 cm depth. By continuously measuring the power required to drill, porosity changes and/or the presence of salt at depth can be mapped. The use of ultrasonic tools enables penetration of the rock with less average force on the stone and a faster progress rate into hard materials without a significant wear effect on the drill bits. Operational settings can be kept constant for different physical properties of the rocks such as compressive strength. Monitoring of the power consumption enables to determine different stone types and the location of salt accumulation/damage in artificially weathered sandstones. Micro-climate monitoring includes the measurement of temperature and humidity changes at the surface of building stones. The analysis enables an identification of areas that suffer from increased stress caused by frequent and high rates of changes in temperature and humidity. A study at four historic buildings was conducted for nearly two years. The sites include the University of Glasgow, Dunkeld Cathedral, Jedburgh Abbey and Fort Charlotte (Shetland Islands). Seasonal changes, stone type and north-south elongation were evaluated for determining rocks with increased weathering risks. The developed techniques provide a more precise identification of stone weathering and allow for better prediction of the decay processes. The techniques allow up-scaling from the lab to the field, and can potentially be used in-situ on historical buildings under site conditions.

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8

Almalki, Majed Ahmed. "Borehole seismic methods in high permeability sandstone". Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/2284.

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In this research complex field borehole seismic measurements are made at a range of frequencies in weakly-consolidated, high-permeability sandstones. New 3D visualisation of phase velocity dispersion derived from multifrequency full waveforms reveals overlapping wave-modes in both open drill holes and sand-screened wells which appear to be sensitive to hydraulic permeability. Multidisciplinary studies of virtual source tomography, vertical seismic profiling and full waveform sonic provide credible information for understanding heterogeneous aquifers with complex sedimentary structures.

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9

Dark, Joshua Peter. "Reservoir Characterization of the Mid-Cretaceous Dakota Formation, Southern Uinta Basin, Utah". Miami University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=miami1214353343.

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10

Maduakor, Ekene Obioma. "Effects of carbon dioxide injection on the displacement of methane and carbonate dissolution in sandstone cores". Texas A&M University, 2006. http://hdl.handle.net/1969.1/4164.

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Previous coreflood experiments show that CO2 sequestration in carbonate rocks is a win-win technology. Injecting CO2 into a depleted gas reservoir for storage also produces hitherto unrecoverable gas. This in turn helps to defray the cost of CO2 sequestration. This thesis reports the results from experiments conducted on a Berea sandstone core. The experiments include displacement experiments and unconfined compressive strength tests. The displacement experiments were conducted at cell pressures of 1500 psig and temperature of 60oC using a 1 foot long and 1 inch diameter Berea sandstone core. Pure CO2 and treated flue gas (99.433 % mole CO2) were injected into the Berea sandstone core initially saturated with methane at a pressure of 1500 psig and 800 psig respectively. Results from these experiments show that the dispersion coefficient for both pure CO2 and treated flue gas are relatively small ranging from 0.18-0.225 cm2/min and 0.28-0.30 cm2/min respectively. The recovery factor of methane at break-through is relatively high ranging from 71%-80% of original gas in place for pure CO2 and 90% to 92% OGIP for treated flue gas, the difference resulting from different cell pressures used. Therefore it would appear that, in practice injection of treated flue gas is a cheaper option compared to pure CO2 injection. For the unconfined compressive strength tests, corefloods were first conducted at high flowrates ranging from 5 ml/min to 20 ml/ min, pressures of 1700-1900 Psig and a temperature of 65oC. These conditions simulate injecting CO2 originating from an electric power generation plant into a depleted gas reservoir and model the near well bore situation. Results from these experiments show a 1% increase in porosity and changes in injectivity due to permeability impairment. The cores are then subjected to an unconfined compressive strength test. Results from these tests do not show any form of weakening of the rock due to CO2 injection.

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11

McKinley, J. M. "Heterogeneity of mineral cements and rock properties in sandstones". Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390882.

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12

Wilkinson, Mark. "Sandstone-hosted concretionary cements of the Hebrides, Scotland". Thesis, University of Leicester, 1989. http://hdl.handle.net/2381/34983.

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The geometries of the sandstone-hosted calcite concretions of the Jurassic Valtos Sandstone Formation and Bearreraig Sandstone Formation are described and related to the processes operating during concretion growth. As concretionary bodies analogous to those studied form potential permeability barriers within some North Sea petroleum reservoirs; the relationship between the growth processes and permeability barrier formation is examined. The growth times for model spherical concretions are calculated for the complex carbonate-water system. Two growth processes are modelled, solute transport and surface reaction. Growth times for a 1m diameter concretion forming under geologically reasonable conditions are predicted to be 22.3Ma, which reduces to 8.8Ma in porewaters flowing at 1m/year. The depth of formation of the concretions is assessed, through an examination of depth dependent properties of both the host-sediment and the calcite cement, and is found to be less than 500m. Concretion formation preceeded the Paleocene igneous activity which affected the Hebrides. The majority of the concretions examined formed at burial depths which were too great to allow effective contact between the concretions and seawater. The major source of carbonate was the dissolution of aragonitic shell material from within the host sandbody. The nature of the porewaters from which the concretions formed is assessed. The majority were meteoric in origin, though some marine influence is noted. The minor element contents of the cements cannot be used to calculate porewater compositions, as disequilibrium between the porewaters and the cements can be demonstrated. A model is proposed to account for the minor element patterns. Crystal breeding can be demonstrated to have occurred during concretion growth. A hypothesis is presented to explain the petrographic features of a typical Valtos Sandstone Formation concretion.

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13

Tsang, Brian Wing Bun. "The origin of the enigmatic Beaver River sandstone". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/MQ31376.pdf.

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14

Dight, Michelle M. "Seismic inversion for porosity in the Showgrounds Sandstone /". Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bd574.pdf.

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15

Solis, Michael P. "TECTONIC CONTROLS ON LOWER DEVONIAN SANDSTONE DISTRIBUTION, ALABAMA". UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/13.

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The Devonian Frog Mountain Formation thickens abruptly eastward across the Eastern Coosa thrust fault from <12 m on the west to>70 m on the east. The thin Frog Mountain on the west unconformably overlies the Cambrian-Ordovician Knox Group. The thin Frog Mountain (mostly shale) is overlain by the Mississippian Maury Shale (~1 m thick) and Fort Payne Chert (~50 m thick). The thick Frog Mountain on the east rests on the Middle Ordovician Athens Shale, a black shale >150 m thick. The Athens overlies the Knox Group. The thick Frog Mountain is nearly all sandstone and is overlain by Fort Payne Chert which is only ~1 m thick In the Eastern Coosa hanging wall, an upper-level out-of-the-syncline thrust fault with thick Frog Mountain in the hanging wall cuts more than 290 m stratigraphically down section from Athens to lower Knox in the footwall. The upper-level Frog Mountain thrust sheet crosses over the Eastern Coosa fault, and truncates folds in the Eastern Coosa footwall, moving ~2 km. The thick Frog Mountain Formation associated with the Eastern Coosa thrust sheet has been transported ~100 km cratonward. The Frog Mountain Formation was deposited over a low topographic high, which was in the location of the Blountian peripheral foreland bulge.

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16

Cheung, See Nga Cecilia. "Experimental deformation in sandstone, carbonates and quartz aggregate". Thesis, State University of New York at Stony Brook, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3717020.

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The first part of my thesis is mainly focused on the effect of grain size distribution on compaction localization in porous sandstone. To identify the microstructural parameters that influence compaction band formation, I conducted a systematic study of mechanical deformation, failure mode and microstructural evolution in Bleurswiller and Boise sandstones, of similar porosity (∼25%) and mineralogy but different sorting. Discrete compaction bands were observed to develop over a wide range of pressure in the Bleurswiller sandstone that has a relatively uniform grain size distribution. In contrast, compaction localization was not observed in the poorly sorted Boise sandstone. My results demonstrate that grain size distribution exerts important influence on compaction band development, in agreement with recently published data from Valley of Fire and Buckskin Gulch, as well as numerical studies.

The second part aimed to improve current knowledge on inelastic behavior, failure mode and brittle-ductile transition in another sedimentary rock, porous carbonates. A micritic Tavel (porosity of ∼13%) and an allochemical Indiana (∼18%) limestones were deformed under compaction in wet and dry conditions. At lower confining pressures, shear localization occurred in brittle faulting regime. Through transitional regime, the deformation switched to cataclastic flow regime at higher confining pressure. Specifically in the cataclastic regime, the (dry and wet) Tavel and dry Indiana failed by distributed cataclastic flow, while in contrast, wet Indiana failed as compaction localization. My results demonstrate that different failure modes and mechanical behaviors under different deformation regimes and water saturation are fundamental prior to any geophysical application in porous carbonates.

The third part aimed to focus on investigating compaction on quartz aggregate starting at low (MPa) using X-ray diffraction. We report the diffraction peak evolution of quartz with increasing pressures. Through evaluating the unit cell lattice parameters and the volume of the quartz sample, macroscopic stress and strain were resolved. Moreover, we observed quartz peak broadened asymmetrically at low pressure, such extent is more prominent in axial than in radial direction. Our evaluation on peak [101] (highest intensity among peaks) demonstrated that full width at half maximum can be a good proxy for microscopic stress distribution. We observed deviations in the pressure-volume curves at P = ∼0.4 GPa and speculated that it was the point of which onset of grain crushing and pore collapse occur in quartz. This is on the same order of which onset of grain crushing (commonly known as P*) is observed in sandstones in the rock mechanics literature. This demonstrated that there is potential in estimating grain crushing and pore collapse pressure with our technique.

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17

Manzocchi, Thomas H. P. "Quantification of flow impairment in faulted sandstone reservoirs". Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/674.

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18

Turkington, Alice V. "The durability of sandstone in salt-rich environments". Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287434.

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19

Wang, Weihua. "Studies of sandstone diagenesis in hydrocarbon-prospective basins". Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333852.

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20

Fernandez, Susana Pombo. "Factors influencing salt-induced weathering of building sandstone". Thesis, Robert Gordon University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286424.

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21

Sansom, Pamela Jane. "Sedimentology of the Navajo Sandstone, southern Utah, USA". Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670285.

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22

Willis, Andrew John. "Non-marine sequence stratigraphy of the Sego Sandstone and Upper Castlegate Sandstone, Upper Cretaceous, Book Cliffs, Utah, United States of America". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27752.pdf.

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23

Szarawarska, Ewa. "Origin of large-scale sandstone intrusions : insights from subsurface case studies and numerical modelling". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=53388.

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Thesis (Ph.D.)--Aberdeen University, 2009.
With: 3D seismic characterization of large-scale sandstone intrusions in the lower Paleogene of the North Sea: completely injected vs in situ remobilized saucer-shaped sand bodies /E. Szarawarska ...et al. In review, Basin Research. Special Issue. Includes bibliographical references.

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24

Birkhead, Stanley Scott. "Architecture of the upper Sego Sandstone, Book Cliffs, Utah". Texas A&M University, 2005. http://hdl.handle.net/1969.1/3326.

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This study maps the facies architecture and geometry of stratigraphic surfaces within the tide-influenced upper Sego Sandstone exposed in the Book Cliffs between Crescent Junction and Thompson Springs, Utah. A bedding diagram was constructed by correlating 32 measured stratigraphic logs across this 8.5 kilometer strike-oblique outcrop to interpret depositional environments and the sequence stratigraphic setting of this tidally-influenced sandstone. Five facies associations are defined: marine shale, lower shoreface, tidally-influenced bedsets, heterolithic tidal bedsets, and tidal flat deposits. Vertical facies trends define two sandy intervals separated by a marine shale, that are interpreted to record episodic progradation of deltaic shorelines. Erosion surfaces at the base of these intervals are interrupted to record tidal scouring of the sea floor during falling stage regression. Sandstone-bodies within these intervals shingle westward recording delta lobes that thinned and became more heterolithic. Although sandstone intervals are interpreted to record progradation, internal cross stratification is dominantly tidal-flood oriented. This is interpreted to record preferential preservation of bedload transported by flood tidal currents onshore, even though net sediment was directed offshore in a suspended ebb-oriented hypopycnal plume and as fluid mud during uncommon river floods. Deposits above high-relief erosion surfaces observed to cut down into the upper Sego Sandstone do not meet the criteria for incised valley fills. These surfaces are interpreted to record tidal current enlargement of distributary channels after abandonment. Such incisions thus do not necessarily record changes in sea level.

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25

Sager, Melissa L. "Petrologic study of the Murrysville sandstone in southwestern Pennsylvania". Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5538.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains ix, 90 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 83-87).

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26

Irvine, Matthew C. "Sandstone canyon development in Starved Rock State Park, Illinois". Virtual Press, 2001. http://liblink.bsu.edu/uhtbin/catkey/1222828.

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In humid environments surface water erosion, rather than seepage water erosion has been considered the major erosional force. The canyons in Starved Rock State Park, north-central Illinois, are not typical in form for eastern United States humid-temperate climate landscapes. In and around Starved Rock State Park the valley cross-profiles are box shaped rather than "V"-shaped with amphitheater heads, steep walls and broad valley bottoms. Other large and small-scale features of the canyons are also largely indicative of seepage erosion.Using field data it was determined that active canyon headwall erosion was occurring in the park at a rate of approximately 0.02 m/year. This is in fact the rate that would be needed to erode the canyons to their current length, showing that seepage erosion, the dominant erosional force in the park, is indeed capable of erosion rates necessary to entirely form the canyons within Starved Rock State Park.
Department of Geology

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27

Monro, M. "Sedimentology of the Carboniferous Fell Sandstone Group of Northumberland". Thesis, University of Newcastle upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374137.

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28

Ryu, Seungoh. "Numerical modeling of the carbonate and the sandstone formations". Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-192171.

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It is of interest in various scientific and industrial contexts to make a reliable estimation of the transport properties of porous media via more accessible probes such as NMR that yield information on static pore geometry and porosity. When the pore geometry is simple, there are empirical recipes that have long proven reliable in bridging the gap. For heterogeneous systems, such recipes fail to give a consistent prediction and invite case-by-case modifications. This is just one of many indications that the complex pore geometry erodes the predictive power of empirical laws that work well in simpler situations. Heterogeneity combined with sizeable diffusive coupling in extended pore space further undermines the validity of the MR interpretation based on simple pore geometry. On top of this, possible spatial variation of surface relaxivity may further complicate the interpretation. Resolution of these issues for real life samples requires elaborate simulations in tandem with experimental verifications on the shared pore geometry. We report on a recent progress which allows combined parallel Lattice Boltzmann and random walk simulations to study transport and diffusion properties in various types of pore geometry, from simple 2D micro-fluidic mazes, 3D glass-bead packs and sandstones to more complex carbonates.

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29

McConnell, Brian James. "Factors controlling sandstone strength and deformability in uniaxial compression". Thesis, University of Bristol, 1989. http://hdl.handle.net/1983/2fde6a20-8069-4e9e-beb9-2c0b867385de.

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30

Ryu, Seungoh. "Numerical modeling of the carbonate and the sandstone formations". Diffusion fundamentals 10 (2009) 17, S. 1-3, 2009. https://ul.qucosa.de/id/qucosa%3A14108.

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Abstract (sommario):

It is of interest in various scientific and industrial contexts to make a reliable estimation of the transport properties of porous media via more accessible probes such as NMR that yield information on static pore geometry and porosity. When the pore geometry is simple, there are empirical recipes that have long proven reliable in bridging the gap. For heterogeneous systems, such recipes fail to give a consistent prediction and invite case-by-case modifications. This is just one of many indications that the complex pore geometry erodes the predictive power of empirical laws that work well in simpler situations. Heterogeneity combined with sizeable diffusive coupling in extended pore space further undermines the validity of the MR interpretation based on simple pore geometry. On top of this, possible spatial variation of surface relaxivity may further complicate the interpretation. Resolution of these issues for real life samples requires elaborate simulations in tandem with experimental verifications on the shared pore geometry. We report on a recent progress which allows combined parallel Lattice Boltzmann and random walk simulations to study transport and diffusion properties in various types of pore geometry, from simple 2D micro-fluidic mazes, 3D glass-bead packs and sandstones to more complex carbonates.

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31

Massart, Benoît Yves Ghislain. "Improved characterisation and modelling of heterolithic tidal sandstone reservoirs". Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24995.

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Tidal heterolithic sandstone reservoirs comprise millimetre- to centimetre-scale intercalations of mudstone and sandstone. Their effective flow properties are poorly predicted by data that do not sample a representative elementary volume (REV), or models that fail to capture the complex 3D architecture of sandstone and mudstone layers. The aim of this dissertation is to develop improved predictions of effective single and multiphase permeabilities in heterolithic tidal sandstones. A surface-based modelling approach has been developed, which honours the geometry of geologic heterogeneity surfaces, integrating easily measurable outcrop derived dataset as input parameters. The workflow uses template surfaces to represent heterogeneities classified by geometry rather than length-scale. The surface-based methodology has been applied to generate generic, 3D mini-models of trough and planar cross-bedded tidal sandstones with differing proportions of sandstone and mudstone. The models closely capture the bedform architectures observed at outcrop and are suitable for flow simulation. Quantitative geometrical input data to construct the models was extracted from an outcrop analogue which records deposition in a tide-dominated deltaic and estuarine setting. The model results demonstrate that effective single-phase permeability of tidal crossbedded sandstones varies with sample volume. A REV of 1 m3 was identified, confirming that the model volume of 9 m3 (> REV) yields representative values. The impact on effective permeability of seven geometric parameters controlling the density of mudstone drapes was determined: mudstone drape coverage, foreset thickness, toeset dip angle, dune climb angle, foreset to toeset ratio, style of cross-bedding (trough or tabular), size of the mudstone drape patches. The impact of seven geometric parameters on effective permeability was determined. Effective permeability decreases as the mudstone fraction increases, and is highly anisotropic. Each parameter investigated can significantly impact on effective permeability, depending upon the flow direction and sandstone fraction, causing considerable spread of the values. During oil/water flow, relative permeabilities are not affected by mudstone drapes, but the irreducible oil saturation varies depending on flow direction and mudstone content. The workflow presented here can be used with subsurface data, supplemented by outcrop analog observations, to generate effective single and multi-phase permeability values to be derived for use in larger-scale reservoir models.

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32

El-Maghraby, Rehab Motasiem Nasr Ali. "Measurements of CO₂ trapping in carbonate and sandstone rocks". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11066.

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CO2 storage in saline aquifers (sandstone/carbonate types) has been proposed as a promising solution to help reduce CO2 emissions to the atmosphere. CO2 will likely be stored as a dense, supercritical (sc.) phase. There are different mechanisms by which CO2 could be stored safely underground; structural and stratigraphic trapping, dissolution trapping, capillary trapping, and mineral trapping. I study capillary trapping. We assume that in the middle of a CO2 plume, many kilometres in extent, the CO2, brine and rock have been in mutual contact for several years. In these circumstances, the degree of capillary trapping is determined by a displacement of CO2 by brine under these equilibrated conditions. Reproducing such conditions in the laboratory poses a challenge. I have measured the first trapping curve, the relation between initial and residual CO2 saturation, for carbonates in the literature, as well as contributing to the first data on sandstones. For capillary trapping experiment, the porous plate method was used during primary drainage. Two sandstones (Berea and Doddington) and two types of carbonates (Ketton and Indiana) were studied. These experiments were conducted at temperatures of 33, 50, and 70 ˚C and 9 MPa pressure, which matches the conditions observed for several current and planned storage sites. Two displacement steps, primary drainage and water flooding were followed to reach residually trapped CO2 saturation. The isothermal de-pressurization method was used to measure the amount of scCO2 residually trapped. The drainage capillary pressure curve, the Leverett J-function and the trapping curve were measured. During capillary trapping experiments, the brine was equilibrated with CO2 to achieve immiscible displacement. We used a stirred reactor, to equilibrate CO2 with brine. The solubility of CO2 in brine was also measured using the isothermal depressurization method and compared with data in the literature.In Berea sandstone the trapping curves at 33, 50 and 70˚C were compared. We showed that temperature (density) variation has no effect on the saturation of scCO2 that is residually trapped. In Doddington sandstone our result was consistent with that from a micro-flow cell in which the trapped scCO2 was imaged using an X-ray source at the pore scale. We find that significant quantities of the CO2 can be trapped, with residual saturations up to 35%, but less than in analogue experiments where oil is displaced by brine. Hence, it is hypothesized that scCO2-brine systems in sandstones are weakly water-wet with less trapping than the more strongly wetting analogues. Capillary trapping in carbonates is very challenging. In carbonates, another step was required, where brine/CO2/carbonate will be equilibrated together before running the capillary trapping experiment. The apparatus used for sandstone rocks was modified so that the geochemical reaction between CO2/rock was accounted for. Samples are taken and analysed to ensure that the brine/CO2 mixture is saturated with carbonate minerals. In Indiana, the CO2 trapping curve for scCO2 at 50 ˚C and 9 MPa was compared with that of gaseous CO2 at 50 ˚C and 4.2 MPa. A scCO2 residual trapping endpoint of 23.7% was observed in Indiana for scCO2, with a smaller trapping end point in Ketton limestone. This indicates a slightly less trapping of scCO2 in carbonates than in sandstone. There is also less trapping for gaseous CO2 (endpoint of 18.8%). The system appears to be more water-wet under scCO2 conditions, which is different from the trend observed in Berea; the greater concentration of Ca2+ in brine at higher pressure was hypothesised to lead to more water-wet conditions. Our work indicates that capillary trapping could effectively store CO2 in carbonate aquifers.

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33

Xu, Xingguang. "A Novel CO2 Flooding Based EOR for Sandstone Reservoirs". Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/51704.

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In an attempt to contribute to the development of CO2-EOR, this project proposes a novel Chemical-Alternating-Foam (CAF) flooding which couples chemical (surfactant and polymer) flooding with the conventional CO2 foam flooding. A new foaming formulation is first developed, and then through systematic and thorough investigations, it is discovered that CAF flooding that applied the developed foaming formulation could be a viable and promising CO2-EOR method for sandstones reservoirs.

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34

Myrin, Malin. "Conservation of Gotland sandstone : overview of present conditions, evaluation of methods /". Göteborg : Acta Universitatis Gothoburgenis, 2006. http://www.loc.gov/catdir/toc/fy0710/2007398714.html.

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35

Scott, Anthony Stephen John. "Processes of sand injection : relationships with host strata, internal structures, and permeability implications". Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=92505.

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Large-scale sandstone injectite complexes located in California and in Tunisia have exposures of external geometries and sedimentary structures. Substantial macroscale erosion occurred along the margins between the injected sandstones and host mudstones that include scalloped upper margins that cut up to 5 m into the overlying host mudstones. Sedimentary structures preserved in the sandstone injectite complexes record fluid-flow, sedimentation and post-sedimentation processes. Bedload layers moving in traction along fluid-sediment interfaces is identified as a significant transport mechanism of grains in sills, low-angle dykes, and irregular injectites, as evidenced by laminae defined by differences grain size, grain composition, and grain packing. High-angle sandstone dykes are characterised by a distinct suite of sedimentary structures that include horizontal bands and pipes. Horizontal bands record the movement of fluidised sand as bands during the waning phase of sand injection. Pipes are interpreted to have formed due to post-sand-injection consolidation and fluid-escape. The distinct sedimentary structures and microtextures that characterise each intrusive element reflect the coupled relationships between the fluid-flow and sedimentation processes and the element type. Sedimentation, post-sedimentation, and diagenetic processes thereafter, resulted in the formation of heterogeneous permeabilities; values vary three-orders-of-magnitude. The heterogeneity is predictable and correlates with the type of intrusive element and its primary and secondary microfabrics. This link demonstrates the influence of primary sedimentation processes and secondary diagenetic processes on the injected sandstone permeability. By constraining the permeability heterogeneity of injected sandstones, it is possible to accurately quantify and thereby anticipate their impact on fluid flow in sedimentary basins.

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36

Welton, Ryan Gregory. "Algal degradation of natural stone masonry : implications for conservation and construction". Thesis, University of the West of Scotland, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269573.

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The objective of this research was to determine the impact of algal colonisation on natural stone masonry. Experimental work was carried out to determine the physical and chemical damage caused by micro-algae using reflected light microscopy, Scanning Electron Microscopy and Inductively Coupled Plasma - Atomic Emission Spectroscopy. Colonisation experiments were performed on individual mineral chips of quartz, calcite, dolomite, siderite, labradorite, orthoclase, a perthitic albite, muscovite and montmorillonite; as well as the Giffnock sandstone, a traditional building stone of the Glasgow area. Work was also carried out to determine the effect of algal colonisation on the absorption of water into a masonry surface. The research determined that algae create an alkaline environment in the areas they colonise. Algal mediated damage to the mineral substrates includes the dissolution and pitting of carbonate surfaces as well as the etching of plagioclase feldspar surfaces. Algal colonisation preferences were noted throughout the experiment with algae preferentially colonising kinks and steps in the topography of mineral surfaces as well as grain edges. Preferences were also seen in the colonisation of the Giffnock sandstone with micas showing heavy colonisation compared to other minerals in the lithology. Algal swelling and contraction cycles were examined in Environmental Scanning Electron Microscopy experiments and the impact that this physical swelling may have on the stone is modelled. Algal biofilms at the surface of the stone lead to an acceleration in the rate at which water enters the surface of the stone, this is important as water is the main weathering catalyst for masonry weathering. The findings of this project implicate algae in the weathering of natural stone masonry through enhanced mineral dissolution, mineral etching and pitting, patina formation, physical weathering through swelling cycles and the alteration of the surface physical properties in relation to water absorption.

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37

Sheldon, Heather Anne. "Numerical modelling of reactive fluid flow and deformation in geological systems". Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272807.

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38

Magoba, Moses. "Petrophysical evaluation of sandstone reservoir of well E-AH1, E-BW1 and E-L1 Central Bredasdorp Basin, offshore South Africa". University of the Western Cape, 2014. http://hdl.handle.net/11394/4462.

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Magister Scientiae - MSc
The Bredasdorp basin is a sub-basin of the greater Outeniqua basin. It is located off the south coast, Southeast of Cape Town, South Africa. This basin is one of the largest hydrocarbon (mainly gas) producing basins within Southern Africa. The petrophysical characteristic of the E-block sandstone units within the Bredasdorp basin has been studied to evaluate their hydrocarbon potential. The data sets used in this research were wireline logs (Las format), core data, and geological well completion reports. The three studied wells are E-AH1, E- BW1 and E-L1. The evaluated interval ranges from 2000.33m to 3303.96m in depth with reference to Kelly bushing within the wells. The sandstone reservoirs of the Bredarsdorp basin are characterized by a range of stacked and amalgamated channels. They originated from materials eroded from pre-existing high stand shelf sandstone and transported into the central Bredarsdorp basin by turbidity current. These sandstones are generally in both synrift and drift section. The basin is thought to have developed from fan deltas and stream overwhelmed to water dominated delta. River dominated deltaic system progresses southward over the Northern edge of the central Bredasdorp basin. The Interactive Petrophysics (IP) software has been used extensively throughout the evaluation and development of interpretation model. The lithofacies of the rock units were grouped according to textural and structural features and grain sizes of well (E-AH1, E-BW1 and E-L1). Four different facies (A, B, C and D) were identified from the cored intervals of each well. Facies A was classified as a reservoir and facies B, C and D as a non-reservoir. Detailed petrophysical analyses were carried out on the selected sandstone interval of the studied wells. The cut-off parameters were applied on the seven studied sandstone interval to distinguish between pay and non-pay sand and all intervals were proved to be producing hydrocarbon. Volume of clay, porosity, water saturation and permeability were calculated within the pay sand interval. The average volume of clay ranged from 23.4% to 25.4%. The estimated average effective porosity ranged from 9.47% to 14.3%. The average water saturation ranged from 44.4% to 55.6%. Permeability ranged from 0.14mD to 79mD. The storage and flow capacity ranged from 183.2scf to 3852scf and 2.758mD-ft to 3081mD-ft respectively. The geological well completion reports classify these wells as a gas producing wells. E-L1 is estimated to have a potential recoverable gas volume of 549.06 cubic feet, E-BW1 is estimated to have 912.49 cubic feet and E-AH1 is estimated to have 279.69 cubic feet.

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39

Persons, Andrea Karen. "Use of the Lowry and Bradford Protein Assays to measure bacterial abundances in a sandstone reservoir". Master's thesis, Mississippi State : Mississippi State University, 2003. http://library.msstate.edu/etd/show.asp?etd=etd-11102003-120611.

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40

Cashman, Amanda L. "Depositional environment analysis of the Pennslyvanian, mid-continent Tonkawa sandstone". Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/11997.

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Master of Science
Department of Geology
Allen W. Archer
Hydrocarbon production throughout the continental United States has declined in past decades. New interpretations together with advanced recovery techniques can increase production in older fields. Re-examining these types of underdeveloped resources is a simple and cost effective tool that can be readily used to increase hydrocarbon production throughout the mid-continent. Pennsylvanian sandstones throughout Oklahoma and Kansas are known for their excellent reservoir qualities. The focus of this study is the upper Pennsylvanian Tonkawa Formation, a sandstone dominated unit. The Tonkawa has been informally correlated to both the Stalnaker and Tonganoxie sandstones in Kansas. Previous publications do not present a unified understanding of the depositional environments that are seen across state borders. The interpretations vary from fluvio-deltaic to marine environments. A cohesive interpretation is necessary to understand paleo-processes and efficiently exploit the reservoir for hydrocarbons. The study presents a regional analysis covering an eleven county area in northwest Oklahoma. Analysis of core and well log data is used to determine the range of depositional environments of the Tonkawa sandstone. Sedimentary structures, mineral assemblages, and lithologies of selected cores are described and correlated with well log data. With this data, structural isopach maps are constructed using Petra software. Earlier interpretations have relied primarily on well log data, focusing on core data rather than geophysical logs, allowing for a more detailed and accurate interpretation. Analysis of transitional sedimentary sequences, such as the Tonkawa, can be applied to sandstones deposited in similar environments throughout the mid-continent.

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41

Akoglu, Kiraz Goze. "Deterioration Of Nemrut Sandstone And Development Of Its Conservation Treatments". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613907/index.pdf.

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In this study, it was aimed to develop conservation methodologies for the historic sandstones using the case of Nemrut Mount Monument to help their survival in open air conditions. The main conservation approach of this study was holistic as well as aiming at minimum intervention targeted to the problem areas. The most important weathering forms of Nemrut Sandstones were material loss due to loss of scales and granular disintegration as well as detachments by scales, back weathering due to loss of scales, cracking, granular disintegration, rounding/notching and discoloration/biological deposition. Deterioration mechanisms of sandstones were studied on deteriorated and relatively sound sandstones by nondestructive methods of UPV and QIRT, and by microstructural analyses using thin section, XRD and SEM-EDX analyses. In addition, the changes in physical and physcomechanical properties such as, color, bulk density, effective porosity, hydric, hygric and thermal dilatation and CEC of clays were determined. Sandstone deterioration was caused by swelling of clay minerals distributed in their matrix and clay accumulations between the detaching scales. Considerable thermal dilatation characteristics was also an important decay factor. Iron oxides caused discoloration at the surfaces, their phase changes was thought to be important in decay. The use of surfactant DAA, to control clay swelling was found to decrease the hydric dilatation by 40%. The consolidation treatments with nanosilica and silicate dispersions namely Funcosil KSE500STE, SytonX3, KSE300 and KSE100 have improved physicomechanical properties as followed by UPV measurements and decreased hydric dilatation. Their long term behaviour needed to be further investigated.

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42

Wu, Tao. "Permeability prediction and drainage capillary pressure simulation in sandstone reservoirs". Texas A&M University, 2004. http://hdl.handle.net/1969.1/1496.

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Knowledge of reservoir porosity, permeability, and capillary pressure is essential to exploration and production of hydrocarbons. Although porosity can be interpreted fairly accurately from well logs, permeability and capillary pressure must be measured from core. Estimating permeability and capillary pressure from well logs would be valuable where cores are unavailable. This study is to correlate permeability with porosity to predict permeability and capillary pressures. Relationships between permeability to porosity can be complicated by diagenetic processes like compaction, cementation, dissolution, and occurrence of clay minerals. These diagenetic alterations can reduce total porosity, and more importantly, reduce effective porosity available for fluid flow. To better predict permeability, effective porosity needs to be estimated. A general equation is proposed to estimate effective porosity. Permeability is predicted from effective porosity by empirical and theoretical equations. A new capillary pressure model is proposed. It is based on previous study, and largely empirical. It is tested with over 200 samples covering a wide range of lithology (clean sandstone, shaly sandstone, and carbonates dominated by intergranular pores). Parameters in this model include: interfacial tension, contact angle, shape factor, porosity, permeability, irreducible water saturation, and displacement pressure. These parameters can be measured from routine core analysis, estimated from well log, and assumed. An empirical equation is proposed to calculate displacement pressure from porosity and permeability. The new capillary-pressure model is applied to evaluate sealing capacity of seals, calculate transition zone thickness and saturation above free water level in reservoirs. Good results are achieved through integration of well log data, production data, core, and geological concepts.

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43

Enman, Travis. "Controls on porosity in the Pab Sandstone, Kirthar Basin, Pakistan /". Title page, contents and executive summary only, 1996. http://web4.library.adelaide.edu.au/theses/09S.B/09s.be58.pdf.

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Thesis (B. Sc.(Hons.))--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 1997.
Volume two consists of 21 folded enclosures in a box. Includes bibliographical references (7 leaves ).

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44

Seth, Siddhartha. "Increase in surface energy by drainage of sandstone and carbonate". Laramie, Wyo. : University of Wyoming, 2006. http://proquest.umi.com/pqdweb?did=1221730011&sid=4&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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45

DuBois, Cale. "Comprehensive design methodology for coal mining under competent sandstone roof". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/6011.

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This thesis presents a logical design methodology for coal mine extraction optimization under massive sandstone roof as developed though a case study analysis of the Quinsam Coal 4 South mine, a shallow underground room and pillar mine with a massive sandstone roof. This research is intended to guide Quinsam Coal and other coal mines globally in efforts to develop or optimize coal extraction and address the geomechanical challenges presented by massive sandstone roof. In this thesis, the tools required to facilitate effective site characterization, ground support design, excavation stability, pillar design, environmental risk management and mining method optimization are presented, as part of a comprehensive design methodology. Guidelines for pillar design are presented based on software assisted gravity-wedge analysis, and review of empirical and analytical design methods. Tools for addressing temporal change in pillar size, shape and stress as well as pillar jointing effects are provided. Pillars are designed to accommodate stresses and strains arising from the known range of overburden depths. An optimized non-caving checkerboard partial pillar extraction method is presented to mitigate environmental risk, address the poor and unpredictable caving mechanics of the massive sandstone roof and provide adequate coal extraction. Modeling of in-line pillar mining and checkerboard partial pillar mining methods was completed with ExamineTAB, a pseudo-3D displacement discontinuity program in support of checkerboard partial pillar mining. Instructional training is required with any modification in mining methods or conditions to apprise the underground workforce on the technical details of the mine design and the importance of adhering to the standards thereof. Using this research work and analysis of the 4 South mine as a backdrop, the design of coal mines under massive sandstone roof is facilitated. The application of the design methodology to the 4 South mine illustrated serves as a 'terms of reference' document for other professionals addressing similar geotechnical and environmental challenges to design safe coal pillar extraction under a massive sandstone roof.

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46

Verlander, Jonathan Edwin. "Basin-scale stratigraphy of the Navajo Sandstone : southern Utah, USA". Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337525.

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47

Clarke, Patrick. "Sedimentological studies in Lower Old Red Sandstone basins, northern Scotland". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335340.

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48

Moss, P. Duncan. "Porewater-rock interaction in the unsaturated zone of sandstone aquifers". Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330002.

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49

Morrissey, Lance Benjamin. "The ichnology of terrestrial palaeoenvironments : Old Red Sandstone, British Isles". Thesis, University of the West of England, Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432317.

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50

Al-Zaidi, Ebraheam Saheb Azeaz. "Experimental studies on displacements of CO₂ in sandstone core samples". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33183.

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CO2 sequestration is a promising strategy to reduce the emissions of CO2 concentration in the atmosphere, to enhance hydrocarbon production, and/or to extract geothermal heat. The target formations can be deep saline aquifers, abandoned or depleted hydrocarbon reservoirs, and/or coal bed seams or even deep oceanic waters. Thus, the potential formations for CO2 sequestration and EOR (enhanced oil recovery) projects can vary broadly in pressure and temperature conditions from deep and cold where CO2 can exist in a liquid state to shallow and warm where CO2 can exist in a gaseous state, and to deep and hot where CO2 can exist in a supercritical state. The injection, transport and displacement of CO2 in these formations involves the flow of CO2 in subsurface rocks which already contain water and/or oil, i.e. multiphase flow occurs. Deepening our understanding about multiphase flow characteristics will help us building models that can predict multiphase flow behaviour, designing sequestration and EOR programmes, and selecting appropriate formations for CO2 sequestration more accurately. However, multiphase flow in porous media is a complex process and mainly governed by the interfacial interactions between the injected CO2, formation water, and formation rock in host formation (e.g. interfacial tension, wettability, capillarity, and mass transfer across the interface), and by the capillary , viscous, buoyant, gravity, diffusive, and inertial forces; some of these forces can be neglected based on the rock-fluid properties and the configuration of the model investigated. The most influential forces are the capillary ones as they are responsible for the entrapment of about 70% of the total oil in place, which is left behind primary and secondary production processes. During CO2 injection in subsurface formations, at early stages, most of the injected CO2 (as a non-wetting phase) will displace the formation water/oil (as a wetting phase) in a drainage immiscible displacement. Later, the formation water/oil will push back the injected CO2 in an imbibition displacement. Generally, the main concern for most of the CO2 sequestration projects is the storage capacity and the security of the target formations, which directly influenced by the dynamic of CO2 flow within these formations. Any change in the state of the injected CO2 as well as the subsurface conditions (e.g. pressure, temperature, injection rate and its duration), properties of the injected and present fluids (e.g. brine composition and concentration, and viscosity and density), and properties of the rock formation (e.g. mineral composition, pore size distribution, porosity, permeability, and wettability) will have a direct impact on the interfacial interactions, capillary forces and viscous forces, which, in turn, will have a direct influence on the injection, displacement, migration, storage capacity and integrity of CO2. Nevertheless, despite their high importance, investigations have widely overlooked the impact of CO2 the phase as well as the operational conditions on multiphase characteristics during CO2 geo-sequestration and CO2 enhanced oil recovery processes. In this PhD project, unsteady-state drainage and imbibition investigations have been performed under a gaseous, liquid, or supercritical CO2 condition to evaluate the significance of the effects that a number of important parameters (namely CO2 phase, fluid pressure, temperature, salinity, and CO2 injection rate) can have on the multiphase flow characteristics (such as differential pressure profile, production profile, displacement efficiency, and endpoint CO2 effective (relative) permeability). The study sheds more light on the impact of capillary and viscous forces on multiphase flow characteristics and shows the conditions when capillary or viscous forces dominate the flow. Up to date, there has been no such experimental data presented in the literature on the potential effects of these parameters on the multiphase flow characteristics when CO2 is injected into a gaseous, liquid, or supercritical state. The first main part of this research deals with gaseous, liquid, and supercritical CO2- water/brine drainage displacements. These displacements have been conducted by injecting CO2 into a water or brine-saturated sandstone core sample under either a gaseous, liquid or supercritical state. The results reveal a moderate to considerable impact of the fluid pressure, temperature, salinity and injection rate on the differential pressure profile, production profile, displacement efficiency, and endpoint CO2 effective (relative) permeability). The results show that the extent and the trend of the impact depend significantly on the state of the injected CO2. For gaseous CO2-water drainage displacements, the results showed that the extent of the impact of the experimental temperature and CO2 injection rate on multiphase flow characteristics, i.e. the differential pressure profile, production profile (i.e. cumulative produced volumes), endpoint relative permeability of CO2 (KrCO2) and residual water saturation (Swr) is a function of the associated fluid pressure. This indicates that for formations where CO2 can exist in a gaseous state, fluid pressure has more influence on multiphase flow characteristics in comparison to other parameters investigated. Overall, the increase in fluid pressure (40-70 bar), temperature (29-45 °C), and CO2 injection rate (0.1-2 ml/min) caused an increase in the differential pressure. The increase in differential pressure with increasing fluid pressure and injection rate indicate that viscous forces dominate the multi-phase flow. Nevertheless, increasing the differential pressure with temperature indicates that capillary forces dominate the multi-phase flow as viscous forces are expected to decrease with this increasing temperature. Capillary forces have a direct impact on the entry pressure and capillary number. Therefore, reducing the impact of capillary forces with increasing pressure and injection rate can ease the upward migration of CO2 (thereby, affecting the storage capacity and integrity of the sequestered CO2) and enhance displacement efficiency. On the other hand, increasing the impact of the capillary force with increasing temperature can result in a more secure storage of CO2 and a reduction in the displacement efficiency. Nevertheless, the change in pressure and temperature can also have a direct impact on storage capacity and security of CO2 due to their impact on density and hence on buoyancy forces. Thus, in order to decide the extent of change in storage capacity and security of CO2 with the change in the above-investigated parameters, a qualitative study is required to determine the size of the change in both capillary forces and buoyancy forces. The data showed a significant influence of the capillary forces on the pressure and production profiles. The capillary forces produced high oscillations in the pressure and production profiles while the increase in viscous forces impeded the appearance of these oscillations. The appearance and frequency of these oscillations depend on the fluid pressure, temperature, and CO2 injection rate but to different extents. The appearance of the oscillations can increase CO2 residual saturation due to the re-imbibition process accompanied with these oscillations, thereby increasing storage capacity and integrity of the injected CO2. The differential pressure required to open the blocked flow channels during these oscillations can be useful in calculating the largest effective pore diameters and hence the sealing efficiency of the rock. Swr was in ranges of 0.38-0.42 while KrCO2 was found to be less than 0.25 under our experimental conditions. Increasing fluid pressure, temperature, and CO2 injection rate resulted in an increase in the KrCO2, displacement efficiency (i.e. a reduction in the Swr), and cumulative produced volumes. For liquid CO2-water drainage displacements, the increase in fluid pressure (60-70 bar), CO2 injection rate (0.4-1ml/min) and salinity (1% NaCl, 5% NaCl, and 1% CaCl2) generated an increase in the differential pressure; the highest increase occurred with increasing the injection rate and the lowest with increasing the salinity. On the other hand, on the whole, increasing temperature (20-29 °C) led to a reduction in the differential pressure apart from the gradual increase occurred at the end of flooding.

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