Author: Chukwuemeka OnaaPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Laboratory and Mathematical-numerical Investigation and Evaluation of Hydrocarbon Migration and Factors Affecting Fluid-flow in Over- and Underlying Formation
Hydrocarbon Migration Systems Analysis
Author: J.M. VerweijPublisher: Elsevier
ISBN: 0080868932
Category : Technology & Engineering
Languages : en
Pages : 289
Book Description
The main intention of this book is to provide geoscientists interested or working in hydrocarbon exploration with a comprehensive understanding of the evolution of hydrocarbon migration systems in sedimentary basins and to give guidelines for its application in basin evaluation. For this purpose, the book fully integrates hydrogeologic and hydrodynamic aspects of the evolution of sedimentary basins with petroleum geologic aspects. It will be of interest to petroleum geologists, hydrogeologists, geochemists and reservoir geologists.
The Evaluation of Subsurface Fluid Migration Using Noble Gas Tracers and Numerical Modeling
Author: William Karl EymoldPublisher:
ISBN:
Category : Fluids
Languages : en
Pages :
Book Description
Fluid flow in the subsurface is a complex phenomenon, significantly affected by geologic characteristics such as porosity and permeability, temperature, compaction, sedimentation, and tectonic processes. The upper crust is often faulted and fractured, and these structural features will alter the inherent geophysical properties of the formations in which they are contained. Because individual techniques used to evaluate crustal fluids, paleo-temperature conditions of formations, and migration pathways each have their own limitations, multidisciplinary approaches must be developed to infer geologic history and past events of fluid flow accurately. In order to interrogate migration pathways and sources of crustal fluids, noble gases have been used to identify mechanisms of fluid flow, hydrocarbon origin, and constrain the temperature conditions of physical processes and chemical reactions. The inert nature and well-constrained sources of noble gases allows them to retain information about geologic history of fluids and rocks over time. Specific isotopic signatures and changes to ratios can distinguish styles of mixing or deformation that occurs during the development of sedimentary basins and orogenic fluid flow. Here, samples collected from the Karoo Basin in South Africa provide an opportunity to analyze the geochemistry of groundwater prior to petroleum exploration. In the Karoo Basin, a field study of the water geochemistry of groundwaters collected before industrial activity showed that naturally-occurring methane was present in the majority of samples and was associated with high salinity and high concentrations of crustal noble gases. The presence of atmospheric noble gases in these samples also suggests fractionation as the natural gas migrated from its source and was emplaced in shallow aquifers. Areas with higher intensity of faulting and fracturing in the Karoo served as preferential pathways during this fluid migration and may still operate that way at present. The effects of faults on fluid flow are further studied in this work by assessing the noble gas distributions along the damage zone of a thrust fault in the Northern Appalachian Basin in New York. Near the fault plane, the 4He concentrations display ~90% loss of the amount predicted and measured in samples further from the fault. The noble gas distribution supports previous fault assessments determined by calculations based on the geometry of the fault core, damage zone, and displacement and suggests that this fault served as a conduit during multiple episodes of fluid flow in the past. Numerical simulations are also beneficial to determine the rates of fluid migration over time and predict advection and diffusion of subsurface fluids based on observed data. By calculating diffusive loss of 4He from quartz grains, predictions can be made regarding the temperature history and permeability of the fault and local system. The formation of gas hydrates in porous sediments beneath the seafloor requires methanogenesis of organic matter and migration of natural gas into appropriate depths where pressure and temperature conditions lead to stability. Calculations based on noble gas observations along the fault damage zone can be used to evaluate retention or release of noble gases in crustal rock and simulations of methane production and migration processes based on input parameters from real world data can be used to predict the occurrence of gas hydrate in Blake Ridge using the flow and transport simulator, PFLOTRAN. By combining field, laboratory, and computational approaches, the results from these interdisciplinary studies offer greater understanding of subsurface flow and can be used to emplace more realistic constraints on geologic inferences.
Rifts and Passive Margins
Author: Michal NemčokPublisher: Cambridge University Press
ISBN: 1107025834
Category : Science
Languages : en
Pages : 619
Book Description
This is a comprehensive synthesis of state-of-the-art information on vitally important hydrocarbon habitats for advanced geology students and researchers, exploration geoscientists, and petroleum managers.
Unsteady-state Fluid Flow
Author: E.J. HoffmanPublisher: Elsevier
ISBN: 0080543456
Category : Technology & Engineering
Languages : en
Pages : 484
Book Description
The ubiquitous examples of unsteady-state fluid flow pertain to the production or depletion of oil and gas reservoirs. After introductory information about petroleum-bearing formations and fields, reservoirs, and geologic codes, empirical methods for correlating and predicting unsteady-state behavior are presented. This is followed by a more theoretical presentation based on the classical partial differential equations for flow through porous media.Whereas these equations can be simplified for the flow of (compressible) fluids, and idealized solutions exist in terms of Fourier series for linear flow and Bessel functions for radial flow, the flow of compressible gases requires computer solutions, read approximations. An analysis of computer solutions indicates, fortuitously, that the unsteady-state behavior can be reproduced by steady-state density or pressure profiles at successive times. This will demark draw down and the transition to long-term depletion for reservoirs with closed outer boundaries.As an alternative, unsteady-state flow may be presented in terms of volume and surface integrals, and the methodology is fully developed with examples furnished. Among other things, permeability and reserves can be estimated from well flow tests.The foregoing leads to an examination of boundary conditions and degrees of freedom and raises arguments that the classical partial differential equations of mathematical physics may not be allowable representations. For so-called open petroleum reservoirs where say water-drive exists, the simplifications based on successive steady-state profiles provide a useful means of representation, which is detailed in the form of material balances. Unsteady-State Fluid Flow provides:• empirical and classical methods for correlating and predicting the unsteady-state behavior of petroleum reservoirs• analysis of unsteady-state behavior, both in terms of the classical partial differential equations, and in terms of volume and surface integrals• simplifications based on successive steady-state profiles which permit application to the depletion of both closed reservoirs and open reservoirs, and serves to distinguish drawdown, transition and long-term depletion performance.
Petroleum Abstracts. Literature and Patents
Author: Origin and Evaluation of Formation Pressures
Author: Dr. Bhagwan SahayPublisher: Allied Publishers
ISBN:
Category : Reservoir oil pressure
Languages : en
Pages : 316
Book Description
On reservoir pressure in oil and gas wells.
Preliminary Investigation of the Nature of Hydrocarbon Migration and Entrapment
Author: Jianyong BaiPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Numerical simulations indicate that hydrocarbon migration and entrapment in stacked fault-bounded reservoirs are mainly affected by the following factors: charge time, faults, pressure and geological structures. The charge time for commercial hydrocarbon accumulation is much longer in oil-water systems than in oil-gas-water systems. Faults are classified into charging faults and 'back doors' faults other than charging faults in stacked fault-bounded reservoirs. The lower the displacement pressure of a fault, the higher its updip oil transportation ability. The downdip oil transportation ability of a fault is usually low and cannot cause commercial downdip oil accumulation. Back doors affect both hydrocarbon percent charge and hydrocarbon migration pathways. Updip back doors improve updip oil charge. The lower the displacement pressure of an updip back door, the more efficient the updip oil charge before 3,000 years. Back doors whose displacement pressure is equal to or higher than 28.76 psi are effective in sealing faults in oil-water systems. On the contrary, only sealing faults result in commercial gas accumulations in stacked fault-compartmentalized reservoirs. Otherwise gas is found over oil. Downdip back doors generally have few effects on downdip hydrocarbon charge. Geopressure enhances the updip oil transportation of a fault and improves the positive effects of updip back doors during updip oil charge. Geopressure and updip back doors result in more efficient updip oil charge. A physical barrier is not necessarily a barrier to oil migration with the aid of geopressure and updip back doors. The chance for hydrocarbon charge into reservoirs along growth faults is not equal. Any one of the above controlling factors can change the patterns of hydrocarbon charge and distribution in such complex geological structures. Generally, lower reservoirs and updip reservoirs are favored. Reservoirs along low-permeability charging faults may be bypassed. Gas can only charge the updip reservoirs. Both updip and downdip back doors can facilitate oil penetrating a barrier fault to charge reservoirs offset by the barrier fault. Interreservoir migration among stacked fault-compartmentalized reservoirs is an important mechanism for hydrocarbon accumulation and trap identification. The interreservoir migration is a very slow process, even though the displacement pressures of bounding faults may be very low.
Origin and Prediction of Abnormal Formation Pressures
Author: George V. ChilingarPublisher: Elsevier Science & Technology
ISBN:
Category : Medical
Languages : en
Pages : 398
Book Description
Knowledge of the presence of abnormally-high pressure zones (AHFP) prior to drilling into them can prevent considerable economic losses and, possibly, save human lives. The various origins (undercompaction, tectonics, etc.) of AHFPs are discussed, followed by the description of predictive techniques in clastic, carbonate and salt-bearing formations. In addition to the well-logging predictive techniques, the authors discuss smectite-illite transformation and the chemistry of interstitial solutions. Other topics covered include (a) abnormally low formation pressures and subsidence, and (b) mathematical modelling. Loss of potential production may result if AHFPs are not properly identified and evaluated. Many hydrocarbon-bearing formations with AHFPs are erroneously "condemned". This book is of interest to engineers and geologists involved in the (a) evaluation, (b) drilling in, (c) completing, and (d) producing from hydrocarbon reservoirs with AHFPs.
Fundamentals of Formation Evaluation
Author: Donald P. HelanderPublisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 354
Book Description
This book will provide a basis for an introductory course in the formation evaluation. It is designed to be supplemented by problems to point out the important concepts.