... reservoir. Eleven genetic layers are identified that are separated by locally developed intraformational seals into up to eight drainage units. High permeability, tidally influenced channel-fill sands have acted as preferential conduits for gas influx, leaving bypassed oil in lower quality sands that were...

...A. J. Rosa; R. N. Horne Summary This work investigates the possibility of characterizing the permeability distribution in areally heterogeneous reservoirs through the interpretation of pressure response to cyclic flow-rate variations. We formulated a mathematical model for the pressure behavior...

...Bijan Agarwal; L. R. Allen; H. E. Farrell Summary The development of a strategy for the detailed three-dimensional (3D) description of permeability was a key ingredient of the recent reservoir characterization study of the Ekofisk field. Because the ultimate objective of this characterization...

...J. E. Nordtvedt; Einar Ebeltoft; J. E. Iversen; André Sylte; Hege Urkedal; K. O. Vatne; A. T. Watson Summary We describe and demonstrate a method for the determination of three-phase relative permeability functions at reservoir conditions. Two- and three-phase displacement experiments are conducted...

...Tono Soeriawinata; Ekrem Kasap; Mohan Kelkar Summary Reservoir simulations are limited to large-scale gridblocks because of prohibitive computational costs of fine-grid simulations. Rock properties, such as permeability, are measured on a scale smaller than coarse-scale simulation gridblocks...

... numerical simulators and thus allows for rapid inversion of multiphase production data. Stochastic permeability fields, conditioned to field-production history, are then generated with simulated annealing. We also explore the spatial resolution associated with estimates of reservoir permeability variations...

...Rajagopal Raghavan; Wei Chun Chu Summary We present a new method to determine average pressure. This method is particularly suited for situations in which no record of the pseudoradial-flow period exists, which is the case in many low-permeability reservoirs. The assumptions of the method we...

... obtained from Stokesian dynamics simulations. The radius and the permeability of the damage zone are calculated by use of a deep-bed filtration model. Equations are derived that allow us to combine the flow resistance in the external and internal filter cakes to obtain the overall decline in injectivity...

.... The measurement frequencies range from 0.5 MHz to 1 MHz. We used Winkler and Plona's 1 pulse-echo method to measure velocity and attenuation (quality factor). The porosity and permeability of the rocks range from 0% to about 20% and 0 to about 5 md, respectively. X-ray diffraction (XRD) analysis, petrological...

...Shahab Mohaghegh; Bogdan Balan; Samuel Ameri Summary We discuss and compare three different approaches for permeability determination from logs from a practical point of view. The three methods, empirical, statistical, and the recently introduced "virtual measurement," make use of empirically...

... enhancement of the petrophysical analysis, and we compare the results in an actual field example. vertical resolution spe formation evaluation resistivity variation log analysis high-resolution clay indicator reservoir saturation permeability mineral porosity conductivity well logging clay...

...Akhil Datta-Gupta; D. W. Vasco; J. C. S. Long Summary This paper examines the sensitivities of interwell tracer and transient-pressure response to spatial distribution of permeability heterogeneity. On the basis of these sensitivities, we describe a formalism to quantify the resolution and spatial...

... the pressure-rate data. When this dataset is subjected to superposition or convolution analysis, results of Fig. 6 show good agreement between the drawdown and buildup analyses. This observation is not surprising because buildup-derived parameters of permeability and skin were input to generate the rate...

...Guoping Xue; Akhil Datta-Gupta; Peter Valkó; Tom Blasingame Summary Conventional multiple regression for permeability estimation from well logs requires a functional relationship to be presumed. Because of the inexact nature of the relationship between petrophysical variables, it is not always...

... nonlinearity explanation macroscopic coefficient flow rate reynolds number upstream oil & gas permeability integral term On the macroscopic scale, fluid flow in a porous medium at low velocity is generally described by Darcy's law, which presents a linear relationship between the driving...

... permeability is substantially larger than the formation permeability. The derivative plots are presented for selected faulted, fractured, channel, and composite reservoirs as diagnostic tools for well-test interpretation. It is also shown that if the composite system's permeability varies moderately in the x...

...G. Pérez; A. K. Chopra Summary Our work uses fractals to characterize the spatial correlation structures of porosity and permeability of vertical and horizontal logs in a braided-fluvial sandstone reservoir. The data comprise cores and logs of adjacent vertical wells and logs of horizontal wells...

...Salih Saner; Mimoun Kissami; Subhi Al Nufaili Summary An experimental relationship between permeability, water saturation, and rock resistivity has been suggested. This relationship can be used for interpreting any one of these three parameters when the other two are known. For example...

...L. D. Ball; P. W. M. Corbett; J. L. Jensen; J. J. M. Lewis Summary For effective flow-simulation models, it may be important to estimate permeability accurately over several scales of geological heterogeneity. Critical to the data analysis and permeability prediction are the volume of investigation...

...S. C. Jones Summary Laboratory pulse-decay measurements using a gas or liquid are effective for determining the permeability of rocks in the range from 0.1 md to 0.01 μ d. The actual measurement time with this pressure-transient technique is fairly short, but pressure pre-equilibration sometimes...