Abstract In 1992, there was a collaborative effort in reservoir geophysics involving Amoco, Conoco, Schlumberger and Stanford University in an attempt to delineate variations in reservoir properties of the Grayburg unit in a West Texas Co2 pilot at North Cowden field. Our objective was to go beyond traveltime tomography in characterizing reservoir heterogeneity and flow anisotropy. This effort involved a comprehensive set of measurements to do traveltime tomography, reflector imaging, analysis of channel waves, shear wave splitting for borehole stress estimation, seismic anisotropy, combined with 3D surface seismic and sonic log interpretation. Results are to be validated with cores and engineering data by history matching of primary, water and CO2 injection performance. The implementation of these procedures should provide critical information on reservoir heterogeneities and preferential flow directions.
Stomach contents analysis was used to quantitatively describe the diet of wahoo, Acanthocybium solandri, from the northcentral Gulf of Mexico. Stomachs were collected opportunistically from wahoo (n = 321) that were weighed (TW, kg) and measured (FL, mm) at fishing tournaments during 1997 - 2007. Stomachs were frozen and later thawed for removal and preservation (95% ethanol) of contents to facilitate their examination and identification. Empty stomachs (n = 71) comprised 22% of the total collection. Unfortunately, the preserved, un-examined contents from 123 stomachs collected prior to Hurricane Katrina (August 2005) were destroyed during the hurricane. Consequently, assessments of wahoo stomach contents reported here were based on the contents of the 65 ‘pre-Katrina’ stomachs, in addition to the contents of 62 stomachs collected ‘post-Katrina’ during 2006 and 2007, for a total of 127 stomachs. Wahoo with prey in their stomachs ranged 859 - 1,773 mm FL and 4.4 - 50.4 kg TW and were sexed as: 31 males, 91 females and 5 sex unknown. Stomach contents reported in this study were identified to the lowest taxon possible (depending on the stage of digestion) and analyzed for %N, %W, %F, IRI y %IRI. Stomachs contained pelagic/epipelagic fishes and squid, including evidence of species associated with pelagic Sargassum. Prey (309 identified items) belonged to 27 taxa and ranged in stomachs from only one prey in 74 stomachs (58% of total stomachs) to 9 prey in a single stomach. Dominant fish families in the diet were Carangidae, Coryphaenidae, Scombridae and Exocoetidae. A moderate ontogenetic shift in the diet was observed among three size classes of wahoo. The diversity of fishes in the diet suggests that wahoo is an opportunistic predator that feeds on a variety of regionally abundant prey.
Microalbuminuria is a known finding in inflammatory states. We hypothesized that urinary albumin/creatinine ratio (ACR) would correlate with injury severity and resuscitation demands after acute burns. This pilot study evaluated 30 adults admitted within 12 hours of injury with burns > or =10% total body surface area burn injury (TBSA). The urinary ACR was calculated for each patient at 7 to 12 hours, 19 to 24 hours, and 43 to 48 hours following burn injury. Microalbuminuria was defined as a urinary ACR > or =20 mg/g. Study patients (23 males, 7 females) had a mean age of 42.9 + 14.0 years and a median TBSA burn injury of 18.8%. Inhalation injury was present in 10 of the study patients, and all patients with inhalation injury had microalbuminuria at the time of admission. One study patient died. Median time from burn injury to resuscitation was 30 hours, and the median fluid requirement was 4.2 ml/kg/%TBSA. Microalbuminuria was not uniformly present in burn-injured patients during the first 48 hours after injury. ACR values early in the hospital course correlated with higher lactate concentrations early after burn injury. However, ACR correlated with neither injury severity nor resuscitation demands after burn injury during any studied time range. Microalbuminuria does not have apparent clinical utility in burn-injured patients, and other markers of injury severity and resuscitation demands should be sought.
An integrated geologic, engineering, and petrophysical evaluation of North McFaddin field, undertaken in cooperation with the current operator. Anaqua Oil and Gas, Inc., targeted actual and potential secondary natural gas resources within thin reservoirs (typically 5-15 ft thick). Funded by the Gas Research Institute, the U.S. Department of Energy, and the State of Texas, this research forms part of the Secondary Gas Recovery project of the Bureau of Economic Geology. Improved vertical resolution of recently developed wireline tools and advances in well-log analytical techniques have been fundamental in identifying these resources. Reservoirs are vertically compartmentalized by nonreservoir facies of subequal thicknesses and collectively are grouped into sequences 75-100 ft thick. Individual reservoirs typically form laterally discontinuous lobes (5000-6000 ft wide) of variable elongation and orientation with respect to inferred depositional dip. Reservoir facies are interpreted to be of distal shoreface origin. Contour maps of net sandstone thickness, relative spontaneous potential deflection, and resistivity were superposed for each reservoir unit. These data were integrated with structure maps and well-test production, wireline-formation test, and sidewall-core data, allowing the potentially productive limits of each reservoir unit to be delineated. By comparing subsequently determined volumes of original gas in place with historical production data,more » potentially recoverable reserves were estimated to be as much as 1000 mmcf for individual reservoirs. These procedures enabled not only the recommendation of recompletion targets, but also suggested a strategic location for a potential development well.« less
ABSTRACT Bypassed, incompletely drained, and untapped gas reservoirs of distal-shoreface origin remain economically important targets for incremental reserve growth within North McFaddin field, located in Victoria County, Texas. The informally termed 4,200-ft No. 5 reservoir serves as an example to illustrate the methods adopted to identify and evaluate reserve additions. Recompletions in existing wellbores and an infill well were recommended to access potential reserves. North McFaddin serves as a model for evaluating the feasibility of developing additional thin-bed resources in other mature gas fields. Recently developed wireline tools and log-evaluation techniques were fundamental in identifying resources. Reservoirs are typically 10 ft or less in thickness and are vertically compartmentalized by nonreservoir facies of subequal thicknesses. Superposed contour maps of net thickness, relative spontaneous potential, and resistivity, integrated with structure maps and well-test-production, wireline-formation-test, and sidewall-core data, enabled the potentially productive limits of each reservoir to be delineated. Potentially recoverable reserves were subsequently determined by comparing volumetric and material-balance calculations of original gas in place with historical production data. Engineering analyses indicated that most reservoirs are characterized by pressure-depletion drive mechanisms. Production and flowing-pressure data of recent thin-bed completions enabled estimation of productivity, drainage volume, and permeability thickness using a radial-flow simulator. Potentially recoverable risked reserves were estimated at approximately 6.5 billion cubic feet of gas. Economic evaluation determined the reservoirs as a cost-effective resource. Thin-bed reservoirs in North McFaddin field illustrate the types of incremental resources that may be common in barrier/strandplain reservoirs from other mature gas fields of the Gulf Coast.
Journal Article Positive Fungal Cultures in Burn Patients: A Multicenter Review Get access James Ballard, BS, James Ballard, BS Search for other works by this author on: Oxford Academic Google Scholar Linda Edelman, RN, Mphil, Linda Edelman, RN, Mphil Search for other works by this author on: Oxford Academic Google Scholar Jeffrey Saffle, MD, Jeffrey Saffle, MD **Address correspondence to Jeffrey R. Saffle, MD, FACS, Dept of Surgery, 3B-306, University of Utah Health Center, 50 N. Medical Drive, Salt Lake City, Utah 84132. Search for other works by this author on: Oxford Academic Google Scholar Robert Sheridan, MD, Robert Sheridan, MD Search for other works by this author on: Oxford Academic Google Scholar Richard Kagan, MD, Richard Kagan, MD Search for other works by this author on: Oxford Academic Google Scholar D Bracco, MD, D Bracco, MD Search for other works by this author on: Oxford Academic Google Scholar Leopoldo Cancio, MD, Leopoldo Cancio, MD Search for other works by this author on: Oxford Academic Google Scholar Bruce Cairns, MD, Bruce Cairns, MD Search for other works by this author on: Oxford Academic Google Scholar Rose Baker, RN, Rose Baker, RN Search for other works by this author on: Oxford Academic Google Scholar Paula Fillari, RN, Paula Fillari, RN Search for other works by this author on: Oxford Academic Google Scholar ... Show more Lucy Wibbenmeyer, MD, Lucy Wibbenmeyer, MD Search for other works by this author on: Oxford Academic Google Scholar David Voight, MD, David Voight, MD Search for other works by this author on: Oxford Academic Google Scholar Tina Palmieri, MD, Tina Palmieri, MD Search for other works by this author on: Oxford Academic Google Scholar David Greenhalgh, MD, David Greenhalgh, MD Search for other works by this author on: Oxford Academic Google Scholar Nathan Kemalyan, MD, Nathan Kemalyan, MD Search for other works by this author on: Oxford Academic Google Scholar Daniel Caruso, MD, Daniel Caruso, MD Search for other works by this author on: Oxford Academic Google Scholar Participating Members of the Multicenter Trials Group, Participating Members of the Multicenter Trials Group Search for other works by this author on: Oxford Academic Google Scholar American Burn Association American Burn Association Search for other works by this author on: Oxford Academic Google Scholar Journal of Burn Care & Research, Volume 29, Issue 1, January-February 2008, Pages 213–221, https://doi.org/10.1097/BCR.0b013e31815f6ecb Published: 01 January 2008
The objectives of this project are to define undrained or incompletely drained reservoir compartments controlled primarily by depositional heterogeneity in a low-accommodation, cratonic Midcontinent depositional setting, and, afterwards, to develop and transfer to producers strategies for infield reserve growth of natural gas. Integrated geologic, geophysical, reservoir engineering, and petrophysical evaluations are described in complex difficult-to-characterize fluvial and deltaic reservoirs in Boonsville (Bend Conglomerate Gas) field, a large, mature gas field located in the Fort Worth Basin of North Texas. The purpose of this project is to demonstrate approaches to overcoming the reservoir complexity, targeting the gas resource, and doing so using state-of-the-art technologies being applied by a large cross section of Midcontinent operators.
The rich gas miscible slug process is generally thought to be applicable only where reservoir pressures are above 1,400 psi. However, the process may be operable at lower pressures under certain conditions. This paper examines criteria for evaluating the applicability of the process and describes the design of one project for a West Texas reservoir having an average pressure of 925 psi. Introduction The various miscible displacement processes hold considerable potential for economically recovering oil otherwise unrecoverable by more conventional processes such as waterflooding. This potential processes such as waterflooding. This potential stems from the fact that displacement efficiencies approaching 100 percent are achieved and thus all oil is recovered from the swept portion of the reservoir. Three factors that have historically limited realization of this potential are (1) poor sweep efficiency resulting from extremely unfavorable mobility ratios, (2) high costs associated with the expensive fluids that are injected, and (3) limited applicability due to the operating pressure requirements that are imposed. Several approaches to the problem of poor sweep efficiency have been proposed, including presolvent water injection, cosolvent water injection, and gaswater injection following solvent placement. The rich gas slug process, with which this paper is concerned, is one possible means of reducing fluid costs, since a mixture of liquefied petroleum gas (LPG) and dry gas is less expensive than pure LPG. The operating pressure limitation, however, is more severe than for a pure LPG slug process. In general, rich gas displacement has been considered applicable only to reservoirs at 1,400 psi or greater. The purposes of this paper are to (1) review some of the purposes of this paper are to (1) review some of the theory of miscible rich gas displacement, (2) examine the limitations imposed on operating pressure, and (3) present engineering calculations and approaches adopted present engineering calculations and approaches adopted in the design of one low-pressure rich gas project in West Texas. An actual field project based on this design is currently being installed. Description of the Process Displacement Mechanism The rich, or condensing, gas drive process utilizes a gas that is rich in intermediate-molecular-weight (C2 through C4) hydrocarbons. Such a gas need not be miscible directly upon contact with the reservoir oil. It is well known that if the gas contains enough intermediates, miscibility will develop after sufficient contact between the gas and the crude. This requires the gas to move for some distance into the reservoir. The mechanism of miscibility development involves transferring (or "condensing") intermediates from the gas to the oil. Upon contact with liquid, the gas is stripped of intermediates and moves on ahead, allowing multiple contacts to occur between incoming gas and the liquid phase. Thus, through a chromatographic type of separation and concentration of components, a liquid transition zone is formed that consists of original reservoir oil at the outward edge, with mixtures gradually richer in intermediates toward the wellbore. If the injected gas is rich enough in intermediates, it eventually contacts a modified liquid phase with which it is directly miscible and an efficient displacement will result. Whether such a miscible zone will develop depends upon the composition of the rich gas and of the reservoir oil, the reservoir temperature, and the operating pressure. JPT P. 599
ABSTRACT Integration of detailed geologic, engineering, and petrophysical analyses, combined with improved well-log analytical techniques, may be used by independent oil and gas companies for successful infield exploration in mature fields in the Gulf Coast that larger companies may consider uneconomic. The secondary gas recovery (SGR) project, conducted by the Bureau of Economic Geology and funded by the Gas Research Institute, the U. S. Department of Energy, and the State of Texas, identified a potential additional natural gas resource of 7.6 billion cubic feet (BCF), of which 3.1 BCF may be recoverable in a 490-acre lease in Agua Dulce field. Five wells in this lease had previously produced 13.7 BCF from Frio reservoirs at depths of 4,600 to 6,200 ft. Pay zones occur in heterogeneous fluvial reservoirs that are offset by faults associated with the Vicksburg Fault Zone. Poorly drained or isolated reservoir compartments occur where channel-fill and crevasse-splay reservoirs are partitioned by these faults. Some compartments may contain <=0.5 BCF of gas resources, based on previous completions and recent infield drilling by Pintas Creek Oil Company, an independent exploration and production company. Uncontacted gas resources at Agua Dulce field occur in thin (typically <10-ft), bypassed zones that can be identified through computed log evaluation integrating open-hole logs, wireline pressure tests, fluid samples, and cores. At Agua Dulce field, such analysis identified a 4-ft bypassed zone uphole from previously produced reservoirs. This reservoir contained original reservoir pressure and flowed at rates exceeding 1 million cubic feet per day. The expected ultimate recovery is 0.4 BCF. Procedures developed in evaluating Agua Dulce field can be successfully applied to other mature gas fields in the South Texas Gulf Coast. For example, Stratton and North McFaddin are two other fields in which the SGR project has demonstrated the existence of thin, potentially bypassed zones that may yield large additional gas resources, extending the economic life of these fields.
Application of the rich gas miscible slug process has generally been considered to be limited to reservoirs with pressures in excess of about 1,400 psi. It has not been widely recognized, however, that applicability is actually limited by the pressure at and behind the displacement front, and not by reservoir pressure, per se. In addition, use of an ethane-rich stream (such as gasoline plant deethanizer overhead) as the base gas for enrichment can often result in significant relief from the pressure limitation. An actual design of a rich gas miscible slug drive for a W. Texas reservoir with an average pressure of approx. 25 psi is described. The process selected consists of injection of a small volume of water followed, in order, by alternate rich gas-water, alternate dry gas-water, and water. The design involved laboratory testing to define a rich gas composition which would remain single phase in the reservoir, miscibly displace the reservoir crude, and be miscibly displaced by the plant residue gas which is available for use as a driving gas. The composition ultimately selected requires an operating pressure of 1,100 psi to meet all of these criteria. This pressure will be maintained at the displacement front bymore » injecting at 3,000 psi into 925 psi reservoir. (13 refs.)« less
