Relative permeability is one of the key parameters governing fluid flow through porous media. Determination of relative permeability is traditionally conducted in the laboratory using either recombined reservoir oil or laboratory oil at simulated reservoir conditions, or simply at laboratory conditions. This is because it is expensive to sample representative uncontaminated reservoir fluids and extremely difficult to cut reservoir cores without altering their surface properties. Restoring rock properties to their original reservoir conditions has been a technical challenge to the industry. Upscaling laboratory special core-analysis data to reservoir scale is also a concern. Consequently, the industry has been researching new methods to extract relative permeability in situ , including the utilization of specially designed permanent downhole electric resistivity array, pressure and flow rate measurements. In this study, a different approach was taken. A semi-analytical model, developed to infer relative permeability from resistivity, was verified using experimental and field data. Relative permeability and resistivity were measured simultaneously in the laboratory. The results demonstrated that relative permeability derived from measured resistivity was close to the measured relative permeability. Relative permeability calculated from resistivity logs in two wells was compared to measured relative permeability with encouraging results.

Relative permeability is one of the key parameters governing fluid flow through porous media. Determination of relative permeability is traditionally conducted in the laboratory using either recombined reservoir oil or laboratory oil at simulated reservoir conditions or simply at laboratory room conditions. This is because it is expensive to sample representative uncontaminated reservoir fluids and extremely difficult to cut reservoir cores without altering their surface properties. Restoring rock properties to their original reservoir conditions has been a technical challenge to the industry. Upscaling laboratory special core analysis data to reservoir scale is also a concern. Consequently, the industry has been researching new methods to extract relative permeability in-situ including using specially designed permanent downhole electric resistivity array measurements.In this study, a different approach was taken. A semianalytical model, developed to infer relative permeability from resistivity, was verified using experimental and field data. Relative permeability and resistivity were measured simultaneously in the laboratory. The results demonstrated that relative permeability derived from measured resistivity were close to the measured relative permeability. Relative permeability calculated from resistivity logs in two wells was compared to measured relative permeability with encouraging results. With this approach, it would be possible to obtain a distribution of relative permeability characteristics throughout an entire reservoir for enhanced reservoir engineering studies.

WB II, et al Tears of the glenoid labrum: MR imaging of 88 arthroscopically confirmed cases Radiology 179. [241][242][243][244][245][246] 1991 Authors' Response: Thank you for allowing us to respond to the letter from Dr. Seeger and colleagues. After further analysis, our results remained the same and correlated well with previous studies,2-5,7 but in contrast to the 100% sensitivity reported by Gross et a1.6 A serious issue for the relationship between clinical orthopaedic surgery and radiologic research has been broached during the questioning of this paper. Clearly the definitions of science have become blurred. Analyzing and reporting the accuracy of a diagnostic test with any true scientific method depends on two factors: the diagnostic test must be classified as either positive or negative and the researcher cannot know the standard answer to the test at the time of the interpretation. Achieving specificities and sensitivities near or equal to 100% is much more easily accomplished when such methods are not followed.A prelude of correspondence occurred between the orthopaedic and radiology departments at UCLA before the two letters published here. Quoting from this directly will evidence the great discrepancy in what some researchers fail to understand as scientific method. &dquo;There is no indication whether 'complete' labral examinations were available for each patient. If, for example, we are given a history of impingement syndrome, the examination may not include a labral evaluation.&dquo; &dquo;It is unclear how 'levels of confidence' as transmitted in written reports were interpreted.&dquo; The surgeon in practice sends the patient for an MRI examination and expects a &dquo;complete&dquo; report every time with a &dquo;clear&dquo; description of the findings for each anatomic structure in the patient's shoulder. A surgeon bases his or her operative plan on the report in hand. If the radiologist chooses to submit deficient reports, then those are the only pieces of information the surgeon has to work with. Our study was based on the radiologic reports sent to the patient's chart by the UCLA musculoskeletal radiology department. It is for this reason that our study represents the true accuracy of the experience of a practicing orthopaedic surgeon as opposed to the unblinded experience of ongoing research interpretations at an academic center.Interpreting MRI scans in the setting of a research project when the research topic is known automatically biases the study and invalidates the conclusions because the radiologists are searching for specific findings and not reading the images in the same manner that the everyday studies surgeons request and rely on are interpreted. This concept is depicted in a quote from Dr. Seeger's paper cited as her reference 1, &dquo;MRIs were reviewed with particular attention paid to the status of the glenoid labrum.&dquo; In the &dquo;new data&dquo; Dr. Seeger has arrived at, the scans were reinterpreted with the knowledge of the surgical reports. In her previous paper...