Sandstone Distribution and Lithofacies of the Triassic Dockum Group, Palo Duro Basin, Texas

The Triassic Dockum Group in the Palo Duro Basin comprises numerous interbedded sequences of coarse- to fine-grained terrigenous elastic sedimentary strata. Within the lower Dockum section, four sandstone-dominated progradational sequences are evident. The sandstone in the first unit exhibits a relatively uniform distribution across the basin due to deposition by broad alluvial fans and fan deltas. In contrast, sandstones in the remaining units and the upper Dockum display uneven distribution as a result of deposition by deltaic and fluvial systems. According to net-sandstone trends, sediment sources for Triassic strata in the Palo Duro Basin indicate deposition from the west, north, and east for the basal unit, predominantly from the east for units 2 and 3, and mixed western and eastern sources for unit 4 and the upper Dockum. Net-sandstone distribution patterns and lithofacies trends suggest proximal depositional environments in the present eastern and northeastern Dockum and more distal environments to the west and southwest. Paleodip appears to have been from east to west over most of the Texas side of the basin, possibly changing in the area of the Texas-New Mexico border. Basement structural elements within the basin were subtly active during deposition and influenced the local accumulation of sandstone. Nine lithofacies in the Dockum can be identified from core samples. Two lacustrine system lithofacies are discernible by claystone, mudstone, and siltstone lithologies. In some instances, these intervals are thick and commonly contain features indicative of subaerial exposure and weathering. Four lithofacies may have been deposited in deltaic environments. Thick siltstone sequences and interbedded siltstone and sandstone sequences represent distal and proximal delta-front deposits, while mudstone was deposited on deltaic mudflats. Interbedded, organic-rich siltstone and sandstone accumulated in swamps on abandoned delta platforms. Two fluvial lithofacies, including delta-distributary-channel fill deposits, are represented by relatively thick sandstone and conglomerate. Fluvial lithofacies encompass bed-load and mixed-load systems. An eolian-flat lithofacies may have formed on distal alluvial-fan sediments.Bureau of Economic Geolog

Edwards Aquifer : water quality and land development in the Austin area, Texas

"Gulf Coast Association of Geological Societies, 44th annual convention, Austin, Texas, 5 October 1994."UT Librarie

Stratigraphic Studies of the Palo Duro Basin: An Update

Stratigraphic studies of the Palo Duro Basin are now in their 8th year. Although the emphasis in these studies now lies in the San Andres Formation (possible repository host rock) and the Wolfcamp Series (sub-repository aquifer), investigations of other units (fig. 1) continue to be carried out as well. This report includes work that was not available for inclusion in last year's (1983) CSR on stratigraphy (Open File Report No. OF-WTWI-1984-30). The section on pre-Pennsylvanian stratigraphy represents the final stages of study of those units. The report detailing structural controls on deposition of the San Andres is part of an ongoing effort to recognize indications of structural or tectonic controls on sedimentation throughout the stratigraphic column in the Palo Duro Basin area. Studies of the Dockum Group are revealing similar controls during the Triassic. Core studies of the Dockum are increasing our resolution of depositional settings in the area.Bureau of Economic Geolog

Turbine Remanufacture - One Option For Reliability And Efficiency Improvement.

LecturePg. 95-110A case study of a remanufacture of a steam turbine is presented. The turbine has been in service for 20 years. Thermal and physical stresses have taken their toll on the turbine casing and supporting hardware. Remanufacture was planned with innovative processes and state-of-the-art component upgrades. A unique heat treatment process was designed to reshape the casing and relieve residual stresses thermally induced into the casing over its operating life. Using heat to reshape the case minimized the amount of remachining time required. A team of three vendors was combined to maximize technical and physical resources and accomplish this task in 24 days. The goals of the remanufacture included: • Recovery of lost horsepower and efficiency due to steam path deterioration • Increase efficiency through the application of packing, tip, and nozzle seal upgrades • Elimination of chronic maintenance problems. Major topics include: • Casing disassembly and damage assessment • Weld restoration of erosion damage and steam path blading • Distortion modelling and evaluation • Heat treatment of case • Assessment of heat treatment results • Machining steps required • Design and installation of retractable packing • Design and installation of tip seals and nozzle seals • Successful startup and operational histor

12-Month Outcomes of the US Patient Cohort in the SONATA Pivotal IDE Trial of Transcervical Ablation of Uterine Fibroids.

Objective: The prospective SONATA pivotal Investigational Device Exemption (IDE) trial was performed in the United States (US) and Mexico to examine the safety and effectiveness of transcervical fibroid ablation (TFA) in the treatment of symptomatic uterine fibroids. This is an analysis of 12-month clinical outcomes in the US cohort. Methods: TFA with the Sonata System was performed on women with symptomatic uterine fibroids. The 12-month co-primary endpoints were reduction in menstrual blood loss and freedom from surgical reintervention. Symptom severity, quality of life, patient satisfaction, safety, and reductions in uterine and fibroid volumes were also evaluated. Results: One hundred twenty-five patients were enrolled and treated in the US. Both co-primary endpoints were achieved in this US-based cohort, as 65.3% of patients reported ≥50% reduction in menstrual bleeding and 99.2% of patients were free from surgical reintervention. Symptom improvement was noted by 97.4% of patients and 98.3% were satisfied. Ninety-five percent of patients reported reduced menstrual bleeding at 12 months, and 86.8% noted \u3e20% reduction. Significant mean improvements at 12 months were realized in both symptom severity and health-related quality of life (33.8 points and 45.8 points, respectively; all P\u3c0.0001). Mean maximal fibroid volume reduction per patient was 63.8%. There was a 0% incidence of device related adverse events. Mean length of stay was 2.5 hrs and 50% of patients returned to normal activity within 1 day. Conclusion: This analysis of US patients in the SONATA pivotal IDE trial demonstrates results consistent with those in the full cohort. TFA with Sonata significantly reduced fibroid symptoms with a low surgical reintervention rate through 12 months. These results support the efficacy and safety of the Sonata system as a first-line treatment for women affected by symptomatic uterine fibroids

Turbine Overhaul Frequency Time Or Performance Based?.

LecturePg. 123-132How long should a turbine run before it is disassembled for inspection and overhaul? This question is increasingly important in today's environment of reduced maintenance and turnaround costs. Many aspects of the degradation in a steam turbine cannot be detected through performance evaluations. Moreover, periodic inspections with a borescope cannot tell the condition of parts of the turbine that cannot be seen. Two large (60,000 hp and 40,000 hp) ethylene plant turbine drives were recently disassembled for inspection after running over l3 years. During the l3 year run, borescope and visual inspections were done at each plant turnaround (about every five years). No evidence of erosion was seen on these borescope examinations. In addition, all operational evidence indicated that there was no reduction in the performance of the turbines. Online vibration monitoring showed no problems. The inspection however, showed several areas of severe erosion in both turbines. The results of these inspections, justification of funds to do the disassembly, and insights into how both jobs were done during a 21 day turnaround window will be discussed

The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b

We present photometry of 13 transits of XO-3b, a massive transiting planet on an eccentric orbit. Previous data led to two inconsistent estimates of the planetary radius. Our data strongly favor the smaller radius, with increased precision: R_p = 1.217 +/- 0.073 R_Jup. A conflict remains between the mean stellar density determined from the light curve, and the stellar surface gravity determined from the shapes of spectral lines. We argue the light curve should take precedence, and revise the system parameters accordingly. The planetary radius is about 1 sigma larger than the theoretical radius for a hydrogen-helium planet of the given mass and insolation. To help in planning future observations, we provide refined transit and occultation ephemerides.Comment: To appear in ApJ [22 pages

X-raying the Beating Heart of a Newborn Star: Rotational Modulation of High-energy Radiation from V1647 Ori

We report a periodicity of ~1 day in the highly elevated X-ray emission from the protostar V1647 Ori during its two recent multiple-year outbursts of mass accretion. This periodicity is indicative of protostellar rotation at near-breakup speed. Modeling of the phased X-ray light curve indicates the high-temperature (~50 MK), X-ray-emitting plasma, which is most likely heated by accretion-induced magnetic reconnection, resides in dense (>~5e10 cm-3), pancake-shaped magnetic footprints where the accretion stream feeds the newborn star. The sustained X-ray periodicity of V1647 Ori demonstrates that such protostellar magnetospheric accretion configurations can be stable over timescales of years.Comment: 26 pages, 10 figure

Gendered nationalism : the gender gap in support for the Scottish National Party

Recent major surveys of the Scottish electorate and of Scottish National Party (SNP) members have revealed a distinct gender gap in support for the party. Men are markedly more likely than women to vote for the SNP and they comprise more than two-thirds of its membership. In this article, we use data from those surveys to test various possible explanations for the disproportionately male support for the SNP. While popular accounts have focused on the gendered appeal of recent leaders and on the party’s fluctuating efforts at achieving gender equality in its parliamentary representation, we find much stronger support for a different explanation. Women are less inclined to support and to join the SNP because they are markedly less supportive of its central objective of independence for Scotland. Since men and women barely differ in their reported national identities, the origins of this gender gap in support for independence presents a puzzle for further research