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Sample records for field south ecdfs

  1. THE TAIWAN ECDFS NEAR-INFRARED SURVEY: ULTRA-DEEP J AND K{sub S} IMAGING IN THE EXTENDED CHANDRA DEEP FIELD-SOUTH

    SciTech Connect

    Hsieh, Bau-Ching; Wang, Wei-Hao; Hsieh, Chih-Chiang; Lin, Lihwai; Lim, Jeremy; Ho, Paul T. P.; Yan Haojing

    2012-12-15

    We present ultra-deep J and K{sub S} imaging observations covering a 30' Multiplication-Sign 30' area of the Extended Chandra Deep Field-South (ECDFS) carried out by our Taiwan ECDFS Near-Infrared Survey (TENIS). The median 5{sigma} limiting magnitudes for all detected objects in the ECDFS reach 24.5 and 23.9 mag (AB) for J and K{sub S} , respectively. In the inner 400 arcmin{sup 2} region where the sensitivity is more uniform, objects as faint as 25.6 and 25.0 mag are detected at 5{sigma}. Thus, this is by far the deepest J and K{sub S} data sets available for the ECDFS. To combine TENIS with the Spitzer IRAC data for obtaining better spectral energy distributions of high-redshift objects, we developed a novel deconvolution technique (IRACLEAN) to accurately estimate the IRAC fluxes. IRACLEAN can minimize the effect of blending in the IRAC images caused by the large point-spread functions and reduce the confusion noise. We applied IRACLEAN to the images from the Spitzer IRAC/MUSYC Public Legacy in the ECDFS survey (SIMPLE) and generated a J+K{sub S} -selected multi-wavelength catalog including the photometry of both the TENIS near-infrared and the SIMPLE IRAC data. We publicly release the data products derived from this work, including the J and K{sub S} images and the J+K{sub S} -selected multi-wavelength catalog.

  2. VizieR Online Data Catalog: ECDFS sources optical/IR counterparts (Bonzini+, 2013)

    NASA Astrophysics Data System (ADS)

    Bonzini, M.; Padovani, P.; Mainieri, V.; Kellermann, K. I.; Miller, N.; Rosati, P.; Tozzi, P.; Vattakunnel, S.

    2015-10-01

    We consider a sample of 883 radio sources detected at 1.4GHz in a deep Very Large Array (VLA) survey of the Extended Chandra Deep Field-South (E-CDFS) that reaches a best rms sensitivity of 6uJy. We used deep Spitzer InfraRed Array Camera (IRAC) and Multiband Imaging Photometer for Spitzer (MIPS) data. The IRAC data were obtained as part of the Spitzer IRAC/MUSYC Public Legacy Survey in the Extended CDF-South (SIMPLE) survey (Damen et al., 2011ApJ...727....1D, Cat. J/ApJ/727/1). It covers an area of about 1600 arcmin2 centred on the E-CDFS. The typical 5σ flux density limits are 1.1, 1.3, 6.3 and 7.6uJy at 3.6, 4.5, 5.8 and 8.0um, respectively. We also use MIPS 24um data from the Far-Infrared Deep Extragalactic Legacy (FIDEL) survey (Dickinson & FIDEL Team, 2007AAS...211.5216D). The E-CDFS has been mapped in the X-ray band by Chandra. A total of 129 radio sources have a counterpart in the 4 Ms observations of the CDFS presented in Xue et al. (2011ApJS..195...10X, Cat. J/ApJS/195/10) and another 99 in the main E-CDFS catalogue by Lehmer et al. (2005ApJS..161...21L, Cat. J/ApJS/161/21) obtained with shallower (250ks) observations in each of four pointings. The list of the X-ray counterparts of the radio sources is given in Bonzini et al. (2012ApJS..203...15B, Cat. J/ApJS/203/15). (1 data file).

  3. CANDELS/GOODS-S, CDFS, and ECDFS: photometric redshifts for normal and X-ray-detected galaxies

    SciTech Connect

    Hsu, Li-Ting; Salvato, Mara; Nandra, Kirpal; Brusa, Marcella; Bender, Ralf; Buchner, Johannes; Brightman, Murray; Georgakakis, Antonis; Donley, Jennifer L.; Kocevski, Dale D.; Guo, Yicheng; Barro, Guillermo; Faber, Sandra M.; Rangel, Cyprian; Willner, S. P.; Ashby, Matthew L. N.; Budavári, Tamás; Szalay, Alexander S.; Dahlen, Tomas; and others

    2014-11-20

    We present photometric redshifts and associated probability distributions for all detected sources in the Extended Chandra Deep Field South (ECDFS). This work makes use of the most up-to-date data from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS) and the Taiwan ECDFS Near-Infrared Survey (TENIS) in addition to other data. We also revisit multi-wavelength counterparts for published X-ray sources from the 4 Ms CDFS and 250 ks ECDFS surveys, finding reliable counterparts for 1207 out of 1259 sources (∼96%). Data used for photometric redshifts include intermediate-band photometry deblended using the TFIT method, which is used for the first time in this work. Photometric redshifts for X-ray source counterparts are based on a new library of active galactic nuclei/galaxy hybrid templates appropriate for the faint X-ray population in the CDFS. Photometric redshift accuracy for normal galaxies is 0.010 and for X-ray sources is 0.014 and outlier fractions are 4% and 5.2%, respectively. The results within the CANDELS coverage area are even better, as demonstrated both by spectroscopic comparison and by galaxy-pair statistics. Intermediate-band photometry, even if shallow, is valuable when combined with deep broadband photometry. For best accuracy, templates must include emission lines.

  4. VizieR Online Data Catalog: Optical spectroscopy of ECDF-S X-ray sources (Silverman+, 2010)

    NASA Astrophysics Data System (ADS)

    Silverman, J. D.; Mainieri, V.; Salvato, M.; Hasinger, G.; Bergeron, J.; Capak, P.; Szokoly, G.; Finoguenov, A.; Gilli, R.; Rosati, P.; Tozzi, P.; Vignali, C.; Alexander, D. M.; Brandt, W. N.; Lehmer, B. D.; Luo, B.; Rafferty, D.; Xue, Y. Q.; Balestra, I.; Bauer, F. E.; Brusa, M.; Comastri, A.; Kartaltepe, J.; Koekemoer, A. M.; Miyaji, T.; Schneider, D. P.; Treister, E.; Wisotski, L.; Schramm, M.

    2010-11-01

    We have acquired optical spectra with the VLT, using the Visible Multi-Object Spectrograph (VIMOS) in Oct-Dec 2004, Jan and Oct 2005, Dec 2007 and Jan-Feb 2008. We have carried out two pointings, each with two different setups, in the northern half of the E-CDF-S field. Optical spectra were also obtained in January of 2007, 2008, and 2010 on Keck II with the Deep Imaging Multi-object Spectrograph (DEIMOS). (3 data files).

  5. Limits on the LyC signal from z ~ 3 sources with secure redshift and HST coverage in the E-CDFS field

    NASA Astrophysics Data System (ADS)

    Guaita, L.; Pentericci, L.; Grazian, A.; Vanzella, E.; Nonino, M.; Giavalisco, M.; Zamorani, G.; Bongiorno, A.; Cassata, P.; Castellano, M.; Garilli, B.; Gawiser, E.; Le Brun, V.; Le Fèvre, O.; Lemaux, B. C.; Maccagni, D.; Merlin, E.; Santini, P.; Tasca, L. A. M.; Thomas, R.; Zucca, E.; De Barros, S.; Hathi, N. P.; Amorin, R.; Bardelli, S.; Fontana, A.

    2016-03-01

    Context. Determining the strength of the Lyman continuum (LyC) and the fraction of LyC escape have implications for the properties of the emitting sources at any redshift, but also for the re-ionization of the Universe at z > 6. Aims: We aim to measure the LyC signal from a sample of sources in the Chandra deep field south. We collect star-forming galaxies (SFGs) and active galactic nuclei (AGN) with accurate spectroscopic redshifts, for which Hubble Space Telescope (HST) coverage and multi-wavelength photometry are available. Methods: We selected a sample of about 200 sources at z ~ 3. Taking advantage of HST resolution, we applied a careful cleaning procedure and rejected sources showing nearby clumps with different colours, which could be lower-z interlopers. Our clean sample consisted of 86 SFGs (including 19 narrow-band selected Lyα emitters) and 8 AGN (including 6 detected in X-rays). We measured the LyC flux from aperture photometry in four narrow-band filters covering wavelengths below a 912 Å rest frame (3.11 < z < 3.53). We estimated the ratio between ionizing (LyC flux) and 1400 Å non-ionizing emissions for AGN and galaxies. Results: By running population synthesis models, we assume an average intrinsic Lν(1400 Å)/Lν(900 Å) ratio of 5 as the representative value for our sample. With this value and an average treatment of the lines of sight of the inter-galactic medium, we estimate the LyC escape fraction relative to the intrinsic value (fescrel(LyC)). We do not directly detect ionizing radiation from any individual SFG, but we are able to set a 1(2)σ upper limit of fescrel(LyC) < 12(24)%. This result is consistent with other non-detections published in the literature. No meaningful limits can be calculated for the sub-sample of Lyα emitters. We obtain one significant direct detection for an AGN at z = 3.46, with fescrel(LyC) = (72 ± 18)%. Conclusions: Our upper limit on fescrel(LyC) implies that the SFGs studied here do not present either the

  6. THE TAIWAN ECDFS NEAR-INFRARED SURVEY: VERY BRIGHT END OF THE LUMINOSITY FUNCTION AT z > 7

    SciTech Connect

    Hsieh, Bau-Ching; Wang, Wei-Hao; Lin, Lihwai; Lim, Jeremy; Ho, Paul T. P.; Yan, Haojing; Karoji, Hiroshi; Tsai, Chao-Wei

    2012-04-10

    The primary goal of the Taiwan ECDFS Near-Infrared Survey (TENIS) is to find well-screened galaxy candidates at z > 7 (z' dropout) in the Extended Chandra Deep Field-South (ECDFS). To this end, TENIS provides relatively deep J and K{sub s} data ({approx}25.3 ABmag, 5{sigma}) for an area of 0.5 Multiplication-Sign 0.5 deg. Leveraged with existing data at mid-infrared to optical wavelengths, this allows us to screen for the most luminous high-z objects, which are rare and thus require a survey over a large field to be found. We introduce new color selection criteria to select a z > 7 sample with minimal contaminations from low-z galaxies and Galactic cool stars; to reduce confusion in the relatively low angular resolution Infrared Array Camera (IRAC) images, we introduce a novel deconvolution method to measure the IRAC fluxes of individual sources. Illustrating perhaps the effectiveness at which we screen out interlopers, we find only one z > 7 candidate, TENIS-ZD1. The candidate has a weighted z{sub phot} of 7.8, and its colors and luminosity indicate a young (45M years old) starburst galaxy with a stellar mass of 3.2 Multiplication-Sign 10{sup 10} M{sub Sun }. The result matches with the observational luminosity function analysis and the semianalytic simulation result based on the Millennium Simulations, which may over predict the volume density for high-z massive galaxies. The existence of TENIS-ZD1, if confirmed spectroscopically to be at z > 7, therefore poses a challenge to current theoretical models for how so much mass can accumulate in a galaxy at such a high redshift.

  7. First Detections of Compact AGN-triggered Radio Cores in RQ AGNs in the ECDFS

    NASA Astrophysics Data System (ADS)

    Prandoni, I.; Maini, A.; Norris, R. P.; Giovannini, G.; Spitler, L. R.

    2016-08-01

    The mechanism triggering the radio emission in Radio-Quiet (RQ) Active Galactic Nuclei (AGN), found to be a relevant component of the faint radio population in deep fields, is hotly debated. Most RQ AGNs are unresolved or barely resolved at a few arcsec scale, comparable to the host galaxy size. RQ AGNs have also been found to share many properties with Star Forming Galaxies (SFG). They have similar radio luminosities and similar optical- /infrared-to-radio flux ratios. Their radio luminosity functions show similar evolutionary trends, and their host galaxies have similar colours, optical morphologies and stellar masses. For all these reasons it was concluded that the radio emission in such RQ AGNs is mainly triggered by star formation (SF). However in the local Universe (z<0.5) it is well known that both AGN and SF processes can contribute to the total radio emission in RQ AGNs (see e.g., Seyfert 2 galaxies), and there is growing evidence that composite SF/AGN systems are common at mid to high redshift (z>1-2). We used the Australian Long Baseline Array to observe a number of RQ AGNs in the Extended Chandra Deep Field South (ECDFS), and we detected compact, high-surface-brightness radio cores in some of them. Our pilot study shows that at least some of the sources classified as radio quiet contain an AGN that can contribute significantly (~50% or more) to the total radio emission. This is a first direct evidence of the presence of such AGN-triggered radio emission in RQ AGNs at cosmological redshifts.

  8. SENSITIVE SEARCH FOR RADIO VARIABLES AND TRANSIENTS IN THE EXTENDED CHANDRA DEEP FIELD SOUTH

    SciTech Connect

    Mooley, K. P.; Kulkarni, S. R.; Horesh, A.; Frail, D. A.; Ofek, E. O.; Miller, N. A.

    2013-05-10

    We report on an analysis of the Extended Chandra Deep Field South (E-CDFS) region using archival data from the Very Large Array, with the goal of studying radio variability and transients at the sub-milliJansky level. The 49 epochs of E-CDFS observations at 1.4 GHz sample timescales from 1 day to 3 months. We find that only a fraction (1%) of unresolved radio sources above 40 {mu}Jy are variable at the 4{sigma} level. There is no evidence that the fractional variability changes along with the known transition of radio-source populations below 1 mJy. Optical identifications of the sources show that the variable radio emission is associated with the central regions of an active galactic nucleus or a star-forming galaxy. After a detailed comparison of the efficacy of various source-finding algorithms, we use the best to carry out a transient search. No transients were found. This implies that the areal density of transients with peak flux density greater than 0.21 mJy is less than 0.37 deg{sup -2} (at a confidence level of 95%). This result is approximately an order of magnitude below the transient rate measured at 5 GHz by Bower et al. but it is consistent with more recent upper limits from Frail et al. Our findings suggest that the radio sky at 1.4 GHz is relatively quiet. For multi-wavelength transient searches, such as the electromagnetic counterparts to gravitational waves, this frequency may be optimal for reducing the high background of false positives.

  9. VizieR Online Data Catalog: A K-selected catalog of the ECDFS from MUSYC (Taylor+, 2009)

    NASA Astrophysics Data System (ADS)

    Taylor, E. N.; Franx, M.; van Dokkum, P. G.; Quadri, R. F.; Gawiser, E.; Bell, E. F.; Barrientos, L. F.; Blanc, G. A.; Castander, F. J.; Damen, M.; Gonzalez-Perez, V.; Hall, P. B.; Herrera, D.; Hildebrandt, H.; Kriek, M.; Labbe, I.; Lira, P.; Maza, J.; Rudnick, G.; Treister, E.; Urry, C. M.; Willis, J. P.; Wuyts, S.

    2010-01-01

    Hildebrandt et al. (2006A&A...452.1121H) have collected all (up until 2005 December) archival UU38BRVI imaging data taken using the Wide Field Imager (WFI) on the ESO MPG 2.2m telescope. We have supplemented the WFI optical data with original z'-band imaging taken using Mosaic-II camera on the CTIO 4m Blanco telescope. The ECDFS data were taken in 2005 January. The new MUSYC NIR imaging consists of two mosaics in the J and K bands obtained using the Infrared Sideport Imager (ISPI) on the CTIO Blanco 4m telescope. The data were taken over the course of 15 nights, in 4 separate observing runs between 2003 January and 2004 February. (3 data files).

  10. The detection of FIR emission from high-redshift star-forming galaxies in the ECDF-S

    NASA Astrophysics Data System (ADS)

    Davies, L. J. M.; Bremer, M. N.; Stanway, E. R.; Lehnert, M. D.

    2013-08-01

    We have used the Large Apex Bolometer Camera Survey of the Extended Chandra Deep Field South to investigate rest-frame far-infrared (FIR) emission from typical star-forming systems (Lyman-break galaxies, LBGs, and Lyman α emitters, LAEs) at redshift 3, 4, 4.5 and 5 (922, 68, 46 and 20 sources, respectively). We initially concentrate on LBGs at z ˜ 3 and select three sub-samples on stellar mass (rest-frame optical brightest, M* > 1010.25 M⊙), extinction-corrected star formation (assuming βUV = -2 and applying a dust attenuation correction, SFRtot > 6.7 M⊙ yr-1) and rest-frame UV magnitude (representing a typical Lyman-break selection with R < 24.43). We produce composite 870 μm images of the typical source in our sub-samples, obtaining ˜4σ detections (0.61, 0.35 and 0.37 mJy, respectively) and suggesting a correlation between FIR luminosity and stellar mass. We apply a similar procedure to our full samples at z ˜ 3, 4, 4.5 and 5 and do not obtain detections - a result that is consistent with a simple scaling between FIR luminosity and stellar mass. In order to constrain the FIR spectral energy distribution (SED) of these systems, we explore their emission at multiple wavelengths spanning the peak of dust emission at z ˜ 3 using the Herschel Spectral and Photometric Imaging Receiver (SPIRE) observations of the field. We obtain detections at multiple wavelengths of both our stellar mass and UV-magnitude-selected samples, and find a best-fitting SED with dust temperatures in the ˜33-41 K range. We calculate FIR luminosity, obscured star formation rates (SFRs) and dust masses and find that a significant fraction of star formation in these systems is obscured. Interestingly, our sample selected on extinction-corrected SFR does not display the large FIR fluxes predicted from its red UV spectral slope. This suggests that the method of assuming an intrinsic UV slope and correcting for dust attenuation may be invalid for this sample - and that these are not in

  11. NO EVIDENCE FOR EVOLUTION IN THE FAR-INFRARED-RADIO CORRELATION OUT TO z {approx} 2 IN THE EXTENDED CHANDRA DEEP FIELD SOUTH

    SciTech Connect

    Mao, Minnie Y.; Huynh, Minh T.; Helou, George; Norris, Ray P.; Dickinson, Mark; Frayer, Dave; Monkiewicz, Jacqueline A.

    2011-04-20

    We investigate the 70 {mu}m far-infrared-radio correlation (FRC) of star-forming galaxies in the Extended Chandra Deep Field South (ECDFS) out to z > 2. We use 70 {mu}m data from the Far-Infrared Deep Extragalactic Legacy Survey (FIDEL), which comprises the most sensitive ({approx}0.8 mJy rms) and extensive far-infrared deep field observations using MIPS on the Spitzer Space Telescope, and 1.4 GHz radio data ({approx}8 {mu}Jy beam{sup -1} rms) from the Very Large Array. In order to quantify the evolution of the FRC, we use both survival analysis and stacking techniques, which we find give similar results. We also calculate the FRC using total infrared luminosity and rest-frame radio luminosity, q{sub TIR}, and find that q{sub TIR} is constant (within 0.22) over the redshift range 0-2. We see no evidence for evolution in the FRC at 70 {mu}m, which is surprising given the many factors that are expected to change this ratio at high redshifts.

  12. Field Problems in the South Bronx.

    ERIC Educational Resources Information Center

    Madrigal, Stasia, Ed.

    1983-01-01

    Articles in this issue of the bulletin of the Hispanic Research Center focus on the problems of collecting demographic and social data in the South Bronx. The introductory article summarizes the contents of this issue. The second (by Lloyd H. Rogler, Osvaldo Barreras, and Rosemary Santana Cooney) is based on the experiences of field workers…

  13. INTERIOR PERSPECTIVE, LOOKING SOUTH SOUTHWEST WITH FIELD SET UP IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR PERSPECTIVE, LOOKING SOUTH SOUTHWEST WITH FIELD SET UP IN FOOTBALL CONFIGURATION. FIELD SEATING ROTATES TO ACCOMMODATE BASEBALL GAMES. - Houston Astrodome, 8400 Kirby Drive, Houston, Harris County, TX

  14. South Arch volcanic field9d\

    USGS Publications Warehouse

    Lipman, P.W.; Clague, D.A.; Moore, J.G.; Holcomb, R.T.

    1989-01-01

    Several young lava fields were imaged by GLORIA sidescan sonar along the Hawaiian Arch south of Hawaii. The largest, 35 by 50 km across, includes a central area characterized by high sonar backscatter and composed of several flow lobes radiating from a vent area. Reflection profiling and sea-floor photography indicate that the central lobes are flat sheet flows bounded by pillowed margins; thin surface sediment and thin palagonite rinds on lava surfaces suggest ages of 1-10 ka. Vents are localized along the arch crest near bases of Cretaceous seamounts. Two dredged flows are basanite and alkalic basalt, broadly similar to rejuvenated-stage and some pre-shield alkalic lavas on the Hawaiian Ridge. Arch volcanism represents peripheral leakage of melt from the Hawaiian hot spot over much larger areas than previously recognized. -Authors

  15. THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC): DEEP MEDIUM-BAND OPTICAL IMAGING AND HIGH-QUALITY 32-BAND PHOTOMETRIC REDSHIFTS IN THE ECDF-S

    SciTech Connect

    Cardamone, Carolin N.; Van Dokkum, Pieter G.; Urry, C. Megan; Brammer, Gabriel; Taniguchi, Yoshi; Gawiser, Eric; Bond, Nicholas; Taylor, Edward; Damen, Maaike; Treister, Ezequiel; Cobb, Bethany E.; Schawinski, Kevin; Lira, Paulina; Murayama, Takashi; Saito, Tomoki; Sumikawa, Kentaro

    2010-08-15

    We present deep optical 18-medium-band photometry from the Subaru telescope over the {approx}30' x 30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC 'BVR' image we find {approx}40,000 galaxies with R {sub AB} < 25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to {approx}2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1 < z < 1.2 and at z {approx}> 3.5. For 0.1 < z < 1.2, we find a 1{sigma} scatter in {Delta}z/(1 + z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1 < z < 1.2. We find that {approx}20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site.

  16. THE EXTENDED CHANDRA DEEP FIELD-SOUTH SURVEY: OPTICAL SPECTROSCOPY OF FAINT X-RAY SOURCES WITH THE VLT AND KECK

    SciTech Connect

    Silverman, J. D.; Mainieri, V.; Rosati, P.; Salvato, M.; Hasinger, G.; Bergeron, J.; Capak, P.; Szokoly, G.; Gilli, R.; Tozzi, P.; Vignali, C.; Alexander, D. M.; Brandt, W. N.; Luo, B.; Rafferty, D.; Xue, Y. Q.; Lehmer, B. D.; Bauer, F. E.

    2010-11-15

    We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the Extended-Chandra Deep Field-South (E-CDF-S) and its central 2 Ms area. New spectroscopic redshifts, up to z = 4, are measured for 283 counterparts to Chandra sources with deep exposures (t {approx} 2-9 hr per pointing) using multi-slit facilities on both VLT (VIMOS) and Keck (DEIMOS), thus bringing the total number of spectroscopically identified X-ray sources to over 500 in this survey field. Since our new spectroscopic identifications are mainly associated with X-ray sources in the shallower 250 ks coverage, we provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, determined by a likelihood routine, and redshifts (both spectroscopic and photometric), that incorporate published spectroscopic catalogs, thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. We demonstrate the remarkable coverage of the luminosity-redshift plane now accessible from our data while emphasizing the detection of active galactic nuclei (AGNs) that contribute to the faint end of the luminosity function (L {sub 0.5-8keV} {approx} 10{sup 43}-10{sup 44} erg s{sup -1}) at 1.5 {approx}< z {approx}< 3 including those with and without broad emission lines. Our redshift catalog includes 17 type-2 QSOs at 1 {approx}< z {approx}< 3.5 that significantly increases such samples (2x). Based on our deepest (9 hr) VLT/VIMOS observation, we identify 'elusive' optically faint galaxies (R {sub mag} {approx} 25) at z {approx} 2-3 based upon the detection of interstellar absorption lines (e.g., O II+Si IV, C II], C IV); we highlight one such case, an absorption-line galaxy at z = 3.208 having no obvious signs of an AGN in its optical spectrum. In addition, we determine accurate distances to eight galaxy groups with extended X-ray emission detected both by Chandra and XMM

  17. Parade field, looking from corner of south Hutton St. And ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Parade field, looking from corner of south Hutton St. And Charlie Kelly Blvd. To the northeast towards the 400 series quarters. - Fitzsimons General Hospital, Bounded by East Colfax to south, Peoria Street to west, Denver City/County & Adams County Line to north, & U.S. Route 255 to east, Aurora, Adams County, CO

  18. VIEW SOUTH TOWARD MOVEABLE FIELD LEVEL SEATS. NOTE RETRACTABLE PENTAGONAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW SOUTH TOWARD MOVEABLE FIELD LEVEL SEATS. NOTE RETRACTABLE PENTAGONAL LIGHT RING GONDOLA SUSPENDED FROM ROOF CUPOLA. SKY LIGHTS PAINTED OVER TO REDUCE GLARE FOR BASEBALL OUTFIELDERS. - Houston Astrodome, 8400 Kirby Drive, Houston, Harris County, TX

  19. Evaluation Field Building in South Asia: Reflections, Anecdotes, and Questions

    ERIC Educational Resources Information Center

    Hay, Katherine

    2010-01-01

    This article examines evaluation field building in South Asia and the role of international collaboration in this field building. The article explores aspects of the supply and demand of development evaluation and the political, historical, and systemic factors that bridge or block evaluation use. The article calls for and suggests elements to…

  20. West Short Pine Hills field, Harding County, South Dakota

    SciTech Connect

    Strothman, B.

    1988-07-01

    The West Short Pine Hills field is a shallow gas field that produces from the Shannon Sandstone Member, on the Camp Crook anticline in southwestern Harding County, South Dakota. The Alma McCutchin 1-17 Heikkila discovery was drilled in the NW1/4, Sec. 17, T16N, R2E, to a depth of 1600 ft and completed in October 1977 for 600 MCFGD from perforations at 1405-1411 ft. To date, 40 gas wells have been completed with total estimated reserves of more than 20 bcf. The field encompasses 12,000 ac, with a current drill-site spacing unit of 160 ac. The field boundaries are fairly well defined, except on the south edge of the field. The wells range in depth from 1250 to 2200 ft, and cost $60,000-$85,000 to drill and complete. Core and log analyses indicate that the field has 70 ft of net pay, with average porosity of 30% and average permeability of 114 md. Most wells have been completed with nitrogen-sand frac. Williston Basin Interstate Pipeline Company of Bismarck, North Dakota, operates a compressor station and 2.5 mi of 4-in. line that connects the field to their 160 in. north-south transmission line to the Rapid City area. Currently, producers are netting $1.10-$1.25/million Btu. The late Mathew T. Biggs of Casper, Wyoming, was the geologist responsible for mapping and finding this gas deposit.

  1. Lyα Emitter Galaxies at z˜ 2.8 in the Extended Chandra Deep Field South. I. Tracing the Large-scale Structure via Lyα Imaging

    NASA Astrophysics Data System (ADS)

    Zheng, Zhen-Ya; Malhotra, Sangeeta; Rhoads, James E.; Finkelstein, Steven L.; Wang, Jun-Xian; Jiang, Chun-Yan; Cai, Zheng

    2016-10-01

    We present a narrowband survey with three adjacent filters for z = 2.8-2.9 Lyman alpha (Lyα) emitter (LAE) galaxies in the Extended Chandra Deep Field South (ECDFS), along with spectroscopic follow-up. With a complete sample of 96 LAE candidates in the narrowband NB466, we confirm the large-scale structure at z ˜ 2.8 suggested by previous spectroscopic surveys. Compared to the blank field detected with the other two narrowband filters NB470 and NB475, the LAE-density excess in NB466 (900 arcmin2) is ˜ 6.0 ± 0.8 times the standard deviation expected at z ˜ 2.8, assuming a linear bias of 2. The overdense large-scale structure in NB466 can be decomposed into four protoclusters, whose overdensities (each within an equivalent comoving volume 153 Mpc3) relative to the blank field (NB470+NB475) are in the range of 4.6-6.6. These four protoclusters are expected to evolve into a Coma-like cluster (M ≥ 1015 M ⊙) at z ˜ 0. We also investigate the various properties of LAEs at z = 2.8-2.9 and their dependence on the environment. The average star formation rates derived from the Lyα, rest-frame UV, and X-ray bands are ˜4, 10, and <16 M ⊙ yr-1, respectively, implying a Lyα escape fraction of 25% ≲ {f}{{ESC}}{Lyα } ≲ 40% and a UV continuum escape fraction of {f}{{ESC}}{{UV,cont}} ≳ 62% for LAEs at z ˜ 2.8. The Lyα photon density calculated from the integrated Lyα luminosity function in the overdense field (NB466) is ˜50% higher than that in the blank field (NB470+NB475), and more bright LAEs are found in the overdense field. The three brightest LAEs, including a quasar at z = 2.81, are all detected in the X-ray band and in NB466. These three LAE-active galactic nuclei contribute an extra 20%-30% Lyα photon density compared to other LAE galaxies. Furthermore, we find that LAEs in overdense regions have larger equivalent width values, bluer U - B and V - R (˜2-3σ) colors compared with those in lower density regions, indicating that LAEs in overdense

  2. Mantle convection pattern and subcrustal stress field under South America

    NASA Technical Reports Server (NTRS)

    Liu, H.-S.

    1980-01-01

    The tectonic, igneous and metallogenic features of South America are discussed in terms of the crustal deformation associated with stresses due to mantle convection as inferred from the high degree harmonics in the geopotential field. The application of Runcorn's model for the laminar viscous flows in the upper mantle to satellite and gravity data results in a convection pattern which reveals the ascending flows between the descending Nazca plate and the overlying South American plate as well as segments of the descending Nazca plate beneath South America. The arc volcanism in South America is shown apparently to be related to the upwelling of high-temperature material induced by the subduction of the Nazca plate, with the South American basin systems associated with downwelling mantle flows. The resulting tensional stress fields are shown to be regions of structural kinship characterized by major concentrations of ore deposits and related to the cordillera, shield and igneous systems and the upward Andean movements. It is suggested that the upwelling convection flows in the upper mantle, coupled with crustal tension, have provided an uplift mechanism which has forced the hydrothermal systems in the basement rocks to the surface.

  3. North south asymmetry in the coronal and photospheric magnetic fields

    NASA Astrophysics Data System (ADS)

    Virtanen, I.; Mursula, K.

    2013-12-01

    Several recent studies have shown that the Heliospheric current sheet (HCS) is southward shifted during about three years in the solar declining phase (the so-called bashful ballerina phenomenon). We study the hemispherical asymmetry in the photospheric and coronal magnetic fields using Wilcox Solar Observatory (WSO) measurements of the photospheric magnetic field since 1976 and the potential field source surface (PFSS) model. Multipole analysis of the photospheric magnetic field shows that during the late declining phase of solar cycles since 1970s, bashful ballerina phenomenon is a consequence of g02 quadrupole term, signed oppositely to the dipole moment. Surges of new flux transport magnetic field from low latitudes to the poles, thus leading to a systematically varying contribution to the g02-term from different latitudes. In the case of a north-south asymmetric flux production this is seen as a quadrupole contribution traveling towards higher latitudes. When the quadrupole term is largest the main contribution comes from the polar latitudes. At least during the four recent solar cycles the g02-term arises because the magnitude of the southern polar field is larger than in the north in the declining phase of the cycle. Magnetic flux is transported polewards by the meridional flow and it is most likely that besides the north-south asymmetric production of the magnetic flux, also the asymmetric transportation may significantly contribute to the observed asymmetry of polar field intensities. The overall activity during solar cycle is not significantly different in the northern and southern hemispheres, but hemispheres tend to develop in a different phase.

  4. View of South TwentySixth Street. Stairs to sports field on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of South Twenty-Sixth Street. Stairs to sports field on right which are seen in photo no. HABS CA-2783-3. Buildings No. 25, 26, 27, seen left to right at rear, looking south - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  5. The South Carolina Coastal Erosion Study: Nearshore Hydrodynamics Field Experiment

    NASA Astrophysics Data System (ADS)

    Haas, K. A.; Voulgaris, G.; Demir, H.; Work, P. A.; Hanes, D. M.

    2004-12-01

    As part of the South Carolina Coastal Erosion Study (SCCES) a nearshore field experiment was carried out for five days in December 2003 just north of Myrtle Beach, South Carolina, providing measurements of the waves, currents and morphological evolution. This experiment occurred concurrently with an extensive field campaign several kilometers offshore which included measurements of the waves and currents on and near a significant sand shoal. The purpose of the nearshore experiment was to aid in the identification of the effect of the offshore shoal on the nearshore processes. The resulting dataset will be used for verification of numerical models being used to investigate the hydrodynamics of the region. The experiment was carried out from December 10 to December 15 and consisted of measurements of the waves and currents, extensive surveys of the bathymetry every day, grab samples of the sediments, and video imagery. The hydrodynamics were measured using two Sontek Triton downward-looking Acoustic Doppler Velocimeters and two Nortek AquaDopp profilers arranged in a cross-shore line from inside the swash to several surf zone widths past the breakers. The bathymetric surveying was accomplished using both a differential GPS system and a total station. Surveying was performed each day in order to capture the morphological changes. On the last day, seven sediment samples were taken along a single cross-section to determine the sediment characteristics across the beach. Additionally, a video camera was located on a balcony of the top floor of a nearby hotel providing an excellent field of view of the entire experimental area. Digital video was captured directly onto a computer during all daylight hours and many control points were surveyed in each day to facilitate rectification of the imagery. A variety of conditions were encountered during the experiment, including two storm fronts which passed through, generating wind speeds up to 15 m/s. The first storm generated

  6. South Fence Road -- Phase 1 field operations summary

    SciTech Connect

    McCord, J.P.; Neel, D.

    1996-03-01

    The South Fence Road (SFR) project is part of the Sandia National Laboratories, New Mexico (SNL/NM) Site-Wide Hydrogeologic Characterization (SWHC) task. The SWHC task has as its objective the reduction of uncertainty about the rate and direction of groundwater flow in the SNL/NM/Kirtland Air Force Base (KAFB) area. The SFR project area is located along the southern boundary of SNL/KAFB. This project area was selected to provide site-specific information related to geology and groundwater hydrology within the Hubbell Spring/Tijeras/Sandia fault complex. Specific objectives included determining the depth to the Santa Fe Group/bedrock contact, the depth to the water table, and the hydrogeologic complexities related to faulting. This report is a basic data report from the first phase of field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-1D and SFR-1S, SFR-2, SFR-3D and SFR-3S, and SFR-4. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.

  7. Incidense of spider mites in South Texas cotton fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The incidence of spider mites was evaluated· in four locations of south Texas between Progreso (Hidalgo Co.) to Bishop (Nueces Co.). This is an area with a south to north transect of 125 miles from south Progreso to north Bishop (respectively).The other two intermediate sampled locations were Harlin...

  8. Spiculitic chert reservoir in Glick Field, South-Central Kansas

    SciTech Connect

    Rogers, J.P.; Longman, M.W.; Lloyd, R.M.

    1995-01-01

    Glick Field, located in Kiowa and Comanche counties of southern Kansas, was discovered in 1957 and has produced more than 362 BCF from Mississippian Osage chert, commonly referred to as the {open_quotes}Chat.{close_quotes} Other {open_quotes}CHAT{close_quotes} reservoirs in Kansas and Oklahoma produce mainly from mixed chert and dolomite beneath the pre-Pennsylvanian unconformity, but Glick Field`s reservoir is dominated by chert containing abundant sponge spicules. Glick Field is a stratigraphic trap with production ending where the spiculitic facies pinches out into tight limestones to the south and west which provide a lateral seal. Additionally, updip, to the northeast, the productive facies is truncated by the unconformity. Reworked chert conglomerates overlying the spiculitic reservoir at the unconformity also produce some gas. The spiculitic chert forming the reservoir was desposited below storm wavebase and grades laterally in all directions into echinoderm and brachiopod-rich skeletal wackestones and lime mudstones. Even where completely silicified, these associated limestone are tight. Thus, the reservoir is an in situ oval-shaped complex of internally brecciated sponge mats and bioherms capped in part by the chert conglomerate. The spiculitic chert contains up to 50% porosity in molds after sponge spicules, matrix micropores and vugs are connected in part by fracture and breccia porosity. Distribution of the sponge bioherms which form the reservoir facies was partly controlled by a subtle change on the shallow Mississippian carbonate shelf from clean skeletal limestones southward into shaly (and probably more anoxic) carbonates known locally as the {open_quotes}Cowley Facies.{close_quotes} The sponge bioherms formed most commonly just updip from this boundary, which can be mapped across southern Kansas. Thus, lithologic mapping provides a potential exploration tool with which to find other stratigraphically trapped spiculitic reservoirs in the area.

  9. Mesospheric Winds and Magnetic Fields from the South Pole

    NASA Astrophysics Data System (ADS)

    Martin, C. L.; Burrows, S. M.; Brown, M. J.; Roberts, E. A.

    2007-12-01

    We show how carbon monoxide (CO) can be used as a tracer of mesospheric neutral wind speeds, by measuring small Doppler shifts in its rotational emission spectrum. Since the altitude range we are most sensitive to is generally inaccessible to many other measurement techniques, this fills a significant experimental gap. Using this method, high-resolution ground-based measurements of mesospheric CO taken from the AST/RO sub-millimeter telescope, located at Amundsen-Scott South Pole Station have been used to calculate wind speeds and column densities over the Antarctic from 2002 to 2005. For more information see Burrows et al. JGR-Atmospheres doi:10.1029/2006JD007993. In addition, the 2→ 1 rotational transition of O18O has been measured and used as a tracer of the mesospheric magnetic field over the Antarctic. We demonstrate how the Zeeman splitting of this molecule was used to measure the Earth's magnetic field during the geomagnetic storm of January 2003.

  10. A Comment on "Evaluation Field Building in South Asia: Reflections, Anecdotes, and Questions"

    ERIC Educational Resources Information Center

    Kumar, A. K. Shiva

    2010-01-01

    This paper presents the author's comment on "Evaluation Field Building in South Asia: Reflections, Anecdotes, and Questions" by Katherine Hay. Hay raises a number of extremely relevant issues relating to evaluation field building in South Asia. In this paper, the author aims to underscore the importance of three priorities for initiating…

  11. Opium Field Detection in South Oxfordshire Using SAR Polarimetry

    NASA Astrophysics Data System (ADS)

    Walker, Nick; Marino, Armando

    2011-03-01

    To-date the use of satellite imagery to monitor the growth of illicit crops such as marijuana, opium and coca has mostly been conducted using optical frequencies. However, it is well known that while optical imagery can be hampered by localised aerosols such as thin clouds, cirrus, haze and smoke, these do not present a problem for Synthetic Aperture Radar (SAR). In recent years a new generation of satellite borne sensors have also been equipped with enhanced polarimetric capabilities, which can potentially help with detecting and classifying different terrain types. For these reasons we believe it is useful to consider whether high resolution polarimetric SAR data can be applied to illicit crop detection.In this paper we present the results of an experiment whereby opium poppy fields were successfully detected in the south Oxfordshire region in the UK using RadarSat-2 quad-polarisation imagery. It should be noted that these crops are not being grown illicitly but instead are being cultivated for medicinal reasons in parts of the UK. It is interesting to note that the poppies cultivated for opium in the UK have white flowers rather than the more familiar red as can be seen from the photograph in Figure 1, which was taken 11 days earlier in the season compared to Figure 4 and Figure 5.

  12. H-band observations of the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Moy, E.; Barmby, P.; Rigopoulou, D.; Huang, J.-S.; Willner, S. P.; Fazio, G. G.

    2003-05-01

    We report results of our H-band survey of the Chandra Deep Field South (CDFS). The observations, made with SofI on the NTT, cover 0.027 square degrees to H< 20.5 and 0.17 square degrees to H< 19.8 (50% completeness limits). In total, 4819 objects were detected, of which 80% are galaxies based on the SExtractor parameter ``stellarity index'' having a value less than 0.5. Our astrometric solutions are in good agreement with those of the Las Campanas Infrared Survey (LCIRS), the COMBO-17, and the ESO-EIS surveys. Our photometry compares satisfactorily with the LCIRS results as well as with GOODS data. Galaxy number counts are ~ 50 000 galaxies per square degree at H< 20.75, in good agreement with those of LCIRS. The object catalog is published electronically at the CDS. The whole catalog is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/403/493}. Based on observations collected at the European Southern Observatory, Chile under programs 66.A-0451 and 68.A-0375.

  13. Michael Young and the Curriculum Field in South Africa

    ERIC Educational Resources Information Center

    Hoadley, Ursula

    2015-01-01

    The paper addresses the question of what we should make of Michael Young's recent work with respect to curriculum theory by considering the particular case of South African curriculum reform. The paper thus traces two trajectories: the evolution of Michael Young's ideas over time and South African curriculum reform in the post-apartheid period.…

  14. Wide Field Imaging of the Hubble Deep Field-South Region III: Catalog

    NASA Technical Reports Server (NTRS)

    Palunas, Povilas; Collins, Nicholas R.; Gardner, Jonathan P.; Hill, Robert S.; Malumuth, Eliot M.; Rhodes, Jason; Teplitz, Harry I.; Woodgate, Bruce E.

    2002-01-01

    We present 1/2 square degree uBVRI imaging around the Hubble Deep Field - South. These data have been used in earlier papers to examine the QSO population and the evolution of the correlation function in the region around the HDF-S. The images were obtained with the Big Throughput Camera at CTIO in September 1998. The images reach 5 sigma limits of u approx. 24.4, B approx. 25.6, V approx. 25.3, R approx. 24.9 and I approx. 23.9. We present a catalog of approx. 22,000 galaxies. We also present number-magnitude counts and a comparison with other observations of the same field. The data presented here are available over the world wide web.

  15. Evaluation Field Building in South Asia: Insights from the Rear View Mirror

    ERIC Educational Resources Information Center

    Grob, George F.

    2010-01-01

    The author enjoyed reading Katharine Hay's ambitious and humbling visions for evaluation field building in South Asia. She has successfully positioned herself on a high mountain with a wonderful set of binoculars that enable her to see the entire evaluation landscape of South Asia. She magically sees and describes significant historical forces and…

  16. FIELD MARGINS AND FORMER MANAGER’S HOUSE, LINDLEY NURSERY COMPLEX SOUTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FIELD MARGINS AND FORMER MANAGER’S HOUSE, LINDLEY NURSERY COMPLEX SOUTH. FACING NORTHWEST - Overhills, Fort Bragg Military Reservation, Approximately 15 miles NW of Fayetteville, Overhills, Harnett County, NC

  17. Non-aligned movement support for South-South collaboration in the field of population and family planning.

    PubMed

    1994-06-01

    There has been increasing interest over the past few years in strengthening direct collaboration among country programs of the Non-Aligned Movement (NAM) to promote development. As such, heads of states and governments of the non-aligned countries met September 1992 to discuss South-South collaboration in promoting development. The resulting "Jakarta Message: a Call for Collective Action and the Democratization of International Relations" stressed the need for a multilateral shift of focus in international relations toward a strengthening of multilateral cooperation for development. Population was one of the few areas specifically addressed at the conference requiring multilateral cooperation. Partially designed to prepare member countries for the 1994 International Conference on Population and Development, the meeting of country ministers called for further talks in the interest of intensifying the exchange of information on NAM countries' population policies and programs, as well as the organization of South-South cooperation and assistance arrangements. The following modalities of cooperation among countries in the field of population were identified: training programs; observation-study tours; technical assistance; internships; long-term high-level training; meetings, seminars, and workshops; high-level visits; cross-national surveys and other joint research; purchase/exchange/donation/loan of contraceptives and other supplies and equipment; joint production of contraceptives and related medical commodities; marketing and trading cooperation; information exchange; and cooperation in collaborating with other NAM countries. The paper also discusses financial resources to support collaboration and offers a proposal of NAM arrangements to strengthen, support, and sustain South-South collaboration.

  18. High Latitude Meridional Flow on the Sun May Explain North-South Polar Field Asymmetry

    NASA Technical Reports Server (NTRS)

    Kosak, Katie; Upton, Lisa; Hathaway, David

    2012-01-01

    We measured the flows of magnetic elements on the Sun at very high latitudes by analyzing magnetic images from the Helioseismic and Magnetic Imager (HMI) on the NASA Solar Dynamics Observatory (SDO) Mission. Magnetic maps constructed using a fixed, and north-south symmetric, meridional flow profile give weaker than observed polar fields in the North and stronger than observed polar fields in the South during the decline of Cycle 23 and rise of Cycle 24. Our measurements of the meridional flow at high latitudes indicate systematic north-south differences. There was a strong flow in the North while the flow in the South was weaker. With these results, we have a possible solution to the polar field asymmetry. The weaker flow in the South should keep the polar fields from becoming too strong while the stronger flow in the North should strengthen the field there. In order to gain a better understanding of the Solar Cycle and magnetic flux transport on the Sun, we need further observations and analyses of the Sun's polar regions in general and the polar meridonal flow in particular.

  19. High Latitude Meridional Flow on the Sun May Explain North-South Polar Field Asymmetry

    NASA Technical Reports Server (NTRS)

    Kosak, Katie; Upton, Lisa; Hathaway, David

    2012-01-01

    We measured the flows of magnetic elements on the Sun at very high latitudes by analyzing magnetic images from the Helioseismic and Magnetic Imager (HMI) on the NASA Solar Dynamics Observatory (SDO) Mission. Magnetic maps constructed using a fixed, and north ]south symmetric, meridional flow profile give weaker than observed polar fields in the North and stronger than observed polar fields in the South during the decline of Cycle 23 and rise of Cycle 24. Our measurements of the meridional flow at high latitudes indicate systematic north ]south differences. There was a strong flow in the North while the flow in the South was weaker. With these results, we have a possible solution to the polar field asymmetry. The weaker flow in the South should keep the polar fields from becoming too strong while the stronger flow in the North should strengthen the field there. In order to gain a better understanding of the Solar Cycle and magnetic flux transport on the Sun, we need further observations and analyses of the Sun fs polar regions in general and the polar meridional flow in particular

  20. High Latitude Meridional Flow on the Sun May Explain North-South Polar Field Asymmetry

    NASA Technical Reports Server (NTRS)

    Kosak, Katie; Upton, Lisa; Hathaway, David

    2012-01-01

    We measured the flows of magnetic elements on the Sun at very high latitudes by analyzing magnetic images from the Helioseismic and Magnetic Imager (HMI) on the NASA Solar Dynamics Observatory (SDO) Mission. Magnetic maps constructed using a fixed, and north-south symmetric, meridional flow profile give weaker than observed polar fields in the North and stronger than observed polar fields in the South during the decline of Cycle 23 and rise of Cycle 24. Our measurements of the meridional flow at high latitudes indicate systematic north-south differences. In the fall of 2010 (when the North Pole was most visible), there was a strong flow in the North while in the spring of 2011 (when the South Pole was most visible) the flow there was weaker. With these results, we have a possible solution to this polar field asymmetry. The weaker flow in the South should keep the polar fields from becoming too strong while the stronger flow in the North should strengthen the field there. In order to gain a better understanding of the Solar Cycle and magnetic flux transport on the Sun, we need further observations and analyses of the Sun s polar regions in general and the polar meridional flow in particular.

  1. Intraplate stress field in South America from earthquake focal mechanisms

    NASA Astrophysics Data System (ADS)

    Assumpção, Marcelo; Dias, Fábio L.; Zevallos, Ivan; Naliboff, John B.

    2016-11-01

    We present an updated compilation of earthquake focal mechanisms in Brazil together with focal mechanisms from the sub-Andean region (mainly from global CMT catalogs). All earthquakes in the sub-Andean region show reverse (majority) or strike-slip faulting mechanisms. Focal mechanisms in Brazil show reverse, strike-slip and normal faulting. Focal mechanisms of nearby earthquakes in the same tectonic environment were grouped and inverted for the stress tensor. In the sub-Andean region, stresses are compressional, as expected, with the principal major compression (S1) roughly E-W, on average. A slight rotation of S1 can be observed and is controlled by the orientation of the Andean plateau. In the sub-Andean region, the intermediate principal stress (S2) is also compressional (i.e., larger than the lithostatic pressure, Sv), a feature that is not always reproduced in numerical models published in the literature. In mid-plate South America stresses seem to vary in nature and orientation. In SE Brazil and the Chaco-Pantanal basins, S1 tends to be oriented roughly E-W with S2 approximately equal to S3. This stress pattern changes to purely compressional (both SHmax and Shmin larger than Sv) in the São Francisco craton. A rotation of SHmax from E-W to SE-NW is suggested towards the Amazon region. Along the Atlantic margin, the regional stresses are very much affected by coastal effects (due to continent/ocean spreading stresses as well as flexural effects from sediment load at the continental margin). This coastal effect tends to make SHmax parallel to the coastline and Shmin (usually S3) perpendicular to the coastline. Few breakout data and in-situ measurements are available in Brazil and are generally consistent with the pattern derived from the earthquake focal mechanisms. Although numerical models of global lithospheric stresses tend to reproduce the main large-scale features in most mid-plate areas, the S1 rotation from ∼E-W in SE Brazil to SE-NW in the Amazon

  2. A brief overview of the history of veterinary field services in South Africa.

    PubMed

    Brückner, Gideon K

    2014-11-14

    The historical evolution of veterinary services in South Africa is closely linked to the colonial history of the past and the eventual political formation of the Union of South Africa in 1910, as well as the establishment of a fully democratic South Africa in 1994. The majority of the early pioneering veterinarians had close links to military activities and were originally mostly of British origin. The appointment of the first colonial chief veterinary officers occurred in the late 1800s. These appointments were dictated by the need to combat devastating animal diseases, such as rinderpest and African horse sickness, mainly because they affected draught oxen (used for travel) and horses (used in combat). Veterinary field services was established in 1962 as a separate functional entity within government services when M.C. Lambrechts became Director of Veterinary Services of South Africa. In the context of this article, veterinary field services refers to that sphere of veterinary service delivery conducted by government-appointed or seconded veterinarians applying disease control and prevention, as required by animal health legislation. Paging through the history of veterinary field services in South Africa confirms that the problems faced by the veterinary services of today were just as real during the times of our pioneers. The pioneers of veterinary services transformed unknown animal diseases into textbook descriptions still used today and also demonstrated the important link to, and use of, the observations made by farmers, as well as the need for continued basic and applied research on animal diseases. This article provided a brief overview of the evolution of veterinary field services and the important role played by pioneers over the last two centuries to make South Africa relatively free and safe from the most important trade-sensitive and economically important animal diseases.

  3. High-Resolution Local Crustal Magnetic Field Modeling of the Martian South Pole

    NASA Astrophysics Data System (ADS)

    Plattner, A.; Simons, F. J.

    2014-12-01

    The Mars Global Surveyor (MGS) satellite mission has brought us a wealth of information about the Martian magnetic field. Besides determining that Mars currently does not possess an active core field, MGS revealed that Mars contains an unexpectedly wide crustal magnetic field intensity range. In its orbit insertion, MGS performed a series of low altitude passes down to around 100 km above surface. During this mission phase the magnetic field measurements were active. In particular the nighttime low-altitude data are of high interest because they contain minimal noise from solar wind. Since these data only cover a small portion of the planet's surface, to date all Martian crustal magnetic field models blend the highest-quality data with lower quality measurements collected either at higher satellite altitudes or during daytime. In this contribution we present a locally inverted crustal magnetic field model for the Martian South Polar region calculated from only the highest-quality MGS data using locally constructed altitude vector Slepian functions. The South Polar region of Mars contains the southern part of the strongly magnetized Terra Sirenum and the area south of the Tharsis volcanic highland. Besides parts of planetary scale features our area of data coverage also contains local features such as the presumably volcanic Australe Montes and the Prometheus impact crater. These ingredients compose a highly heterogeneous crustal magnetic field. We show that even for our dense low-altitude low-noise data set the inversion for the crustal magnetic field of a weakly magnetized region adjacent to a region containing a strong magnetic field leads to artifacts in the weak region. With our local method we can avoid these artifacts by selecting subregions of roughly homogeneous field intensity and individually invert for crustal magnetic fields from data within only these subregions. This regional and subregional modeling allows us to reveal previously obscured crustal

  4. Four p67 alleles identified in South African Theileria parva field samples.

    PubMed

    Sibeko, Kgomotso P; Geysen, Dirk; Oosthuizen, Marinda C; Matthee, Conrad A; Troskie, Milana; Potgieter, Frederick T; Coetzer, Jacobus A W; Collins, Nicola E

    2010-02-10

    Previous studies characterizing the Theileria parva p67 gene in East Africa revealed two alleles. Cattle-derived isolates associated with East Coast fever (ECF) have a 129bp deletion in the central region of the p67 gene (allele 1), compared to buffalo-derived isolates with no deletion (allele 2). In South Africa, Corridor disease outbreaks occur if there is contact between infected buffalo and susceptible cattle in the presence of vector ticks. Although ECF was introduced into South Africa in the early 20th century, it has been eradicated and it is thought that there has been no cattle to cattle transmission of T. parva since. The variable region of the p67 gene was amplified and the gene sequences analyzed to characterize South African T. parva parasites that occur in buffalo, in cattle from farms where Corridor disease outbreaks were diagnosed and in experimentally infected cattle. Four p67 alleles were identified, including alleles 1 and 2 previously detected in East African cattle and buffalo, respectively, as well as two novel alleles, one with a different 174bp deletion (allele 3), the other with a similar sequence to allele 3 but with no deletion (allele 4). Sequence variants of allele 1 were obtained from field samples originating from both cattle and buffalo. Allele 1 was also obtained from a bovine that tested T. parva positive from a farm near Ladysmith in the KwaZulu-Natal Province. East Coast fever was not diagnosed on this farm, but the p67 sequence was identical to that of T. parva Muguga, an isolate that causes ECF in Kenya. Variants of allele 2 were obtained from all T. parva samples from both buffalo and cattle, except Lad 10 and Zam 5. Phylogenetic analysis revealed that alleles 3 and 4 are monophyletic and diverged early from the other alleles. These novel alleles were not identified from South African field samples collected from cattle; however allele 3, with a p67 sequence identical to those obtained in South African field samples from

  5. VizieR Online Data Catalog: Chandra Deep Field-South ATLAS 5.5GHz DR2 (Huynh+, 2015)

    NASA Astrophysics Data System (ADS)

    Huynh, M. T.; Bell, M. E.; Hopkins, A. M.; Norris, R. P.; Seymour, N.

    2016-06-01

    The eCDFS was observed with the CABB on the ATCA with the full 2048 MHz bandwidth centred at 5.5GHz. We chose a 42 pointing hexagonal mosaic with spacings of 5-arcmin (approximately 0.5FWHM of the primary beam) to uniformly sample the full 30-arcminx30-arcmin eCDFS region, centred approximately at RA=3:32:22 and DE=-27:48:37 (J2000). The 20h in 2009 and 144h in 2010 were allocated under ATCA observing programme C2028. This data resulted in a rms sensitivity of 11.9uJy and synthesized beam size of 4.9-arcsecx2.0-arcsec (Huynh et al., 2012, Cat. J/MNRAS/426/2342, H12), under hereafter Epoch 1 and Data Release 1 (DR1). Further observations were obtained in 2012 via ATCA programme C2670. The C2670 programme was conceived as a blind search for sub-mJy level sources that are variable on time-scales of months to roughly a year, with a secondary goal of testing the Variables and Slow Transients (VAST) data pipeline. A total of 54h in 2012 May-June (Epoch 2) and 47h in 2012 August (Epoch 3) was allocated to C2670, and the data was taken using the mosaicking strategy of H12. (3 data files).

  6. Synthesis of Moored Observations Collected During the IWISE 2011 Field Program in the South China Sea

    DTIC Science & Technology

    2015-09-30

    IWISE 2011 Field Program in the South China Sea Steven R. Ramp Soliton Ocean Services, Inc. 691 Country Club Drive Monterey, CA 93924 phone...internal waves in the mid -thermocline region have a profound effect on navigation and acoustic propagation. Improved understanding and predictive...Alford (SIO), and J. Nash (OSU). Travel funds to facilitate collabration with international colleagues was provided via Soliton Ocean Services, Inc

  7. New constraints on historical dipole field decay: Four centuries of archaeointensity from Cape Town, South Africa.

    NASA Astrophysics Data System (ADS)

    Hare, V. J.; Gallet, Y.; Genevey, A.

    2015-12-01

    Current global geomagnetic field models suffer from strong bias towards Northern Hemisphere data. Absolute intensity measurements from the Southern Hemisphere are key to understanding the evolution of the field over the historical era, especially recent strengthening of non-dipole contributions, and the appearance of the South Atlantic Magnetic Anomaly (SAMA). I present the first archaeointensity data for locally-fired historical bricks from several well-dated sites (1660-2009 AD) in Cape Town, South Africa. These data constitute the first archaeomagnetic intensity variation curve for southern Africa for the past few centuries. The ages of the sites are tightly constrained by historical and archaeological considerations. Archaeointensity data obtained by the Thellier and Thellier method (modified by Coe), are corrected for both TRM anisotropy and cooling rate dependence of TRM acquisition. Analysis of magnetic mineralogy was performed to aid selection of fragments. Reliable archaeointensity determinations were obtained for 48 of 80 specimens, and 45 were retained in the final analysis. Intensity results vary from 24.3 ± 0.6 μT (modern brick) to 40.7 ± 0.8 μT (1660 AD), corresponding to Virtual Axial Dipole Moments (VADMs) between 6.1 ± 0.2 and 10.2 ± 0.2 נ1022 Am2. Results are generally not in agreement with current field models, but are coherent with other archaeomagnetic datasets from the Southern Hemisphere. The possible reasons for this are discussed, as well as implications for the historical evolution of the field.

  8. Maps showing geology, oil and gas fields, and geological provinces of South America

    USGS Publications Warehouse

    Schenk, C. J.; Viger, R.J.; Anderson, C.P.

    1999-01-01

    This digitally compiled map includes geology, geologic provinces, and oil and gas fields of South America. The map is part of a worldwide series on CD-ROM by World Energy Project released of the U.S. Geological Survey . The goal of the project is to assess the undiscovered, technically recoverable oil and gas resources of the world and report these results by the year 2000. For data management purposes the world is divided into eight energy regions corresponding approximately to the economic regions of the world as defined by the U.S. Department of State. South America (Region 6) includes Argentina, Bolivia, Brazil, Chile, Columbia, Ecuador, Falkland Islands, French Guiana, Guyuna, Netherlands, Netherlands Antilles, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, and Venezuela.

  9. Study on the time difference of solar polar field reversal between the north and south hemisphere

    NASA Astrophysics Data System (ADS)

    Shukuya, D.; Kusano, K.

    2013-12-01

    Dynamo is a mechanism whereby the kinetic energy of plasma is converted to the magnetic energy. This mechanism works to generate and maintain the solar and stellar magnetic field. Since the sun is only a star whose magnetic field can be directly observed, the understanding of solar dynamo can provide clues to clarify dynamo mechanisms. On the other hand, because solar activities, which are caused by solar dynamo, can influence the Earth's climate, solar variability is an important issue also to understand long-term evolution of the Earth's climate. It is widely known that the polarity of the solar magnetic fields on the north and south poles periodically reverses at every sunspot maxima. It is also known that the reversal at one pole is followed by that on the other pole. The time difference of magnetic field reversal between the poles was first noted by Babcock (1959) from the very first observation of polar field. Recently, it was confirmed by detailed observations with the HINODE satellite (Shiota et al. 2012). Svalgaard and Kamide (2013) indicated that there is a relationship between the time difference of the polarity reversal and the hemispheric asymmetry of the sunspot activity. However, the mechanisms for the hemispheric asymmetry are still open to be revealed. In this paper, we study the asymmetric feature of the solar dynamo based on the flux transport dynamo model (Chatterjee et al. 2004) to explain the time difference of magnetic polarity reversal between the north and south poles. In order to calculate long-term variations of solar activities, we use the mean field kinematic dynamo model, which is derived from magnetohydrodynamics (MHD) equation through the mean field and other approximations. We carried out the mean field dynamo simulations using the updated SURYA code which was developed originally by Choudhuri and his collaborators (2004). We decomposed the symmetric and asymmetric components of magnetic field, which correspond respectively to the

  10. AGN on the color-magnitude diagram: Results from a Deep Medium Band Survey with the Subaru Telescope in the MUSYC-ECDFS Region

    NASA Astrophysics Data System (ADS)

    Cardamone, Carolin; Urry, C. Megan; van Dokkum, P.; Schawinski, Kevin; Gawiser, E.; Brammer, G.; Taylor, N.; Treister, E.; Taniguchi, Y.; Virani, S.

    2009-09-01

    We investigate the host galaxy colors of X-ray detected AGN in the Extended Chandra Deep Field South.We have conducted deep medium-band imaging with the Subaru telescope, in 18 filters from 427 nm to 856 nm, of the MUSYC survey field. We detect 80,000 galaxies to equivalent magnitude R 27 mag, of which approximately 1,000 are X-ray-detected AGN observed with Chandra and XMM. Combining the Subaru data with optical, IR data and IRAC photometry we obtain photometric redshifts using EAZY, a fast public photometric redshift code, in the range 0

  11. The Upper Mantle Flow Field around South-Africa as Reflected by Isotopic Provinciality

    NASA Astrophysics Data System (ADS)

    Meyzen, C.; Blichert-Toft, J.; Ludden, J.; Humler, E.; Mevel, C.; Albarede, F.

    2006-12-01

    Isotopic studies of MORB have established the existence of broad isotopic provinces within the underlying asthenosphere, such as in the Indian Ocean (DUPAL). How these features relate to mantle circulation is, however, still unknown. The steepness of the transition between such isotopic provinces will define the geometry of the velocity field in the upper mantle. In this respect, the transition between the Indian and South Atlantic provinces, two domains that are isotopically contrasted, should be readily identifiable over this long ridge segment. Here, we present Hf isotope data for 60 samples dredged along the SWIR between 35° and 69°E. The new Hf isotope data show that the Indian asthenosphere does not spill directly into the South Atlantic upper mantle: the general decreasing southward gradient observed for ^{176}Hf/^{177}Hf down the mid- Atlantic Ridge, and also for Sr isotopes and model Th/U ratios (derived from Pb isotopes), is overprinted by material with radiogenic Sr, unradiogenic Hf and high Th/U. The Indian domain grades into the South Atlantic around Bouvet, while the South Atlantic collides with the Atlantic province around Tristan. We interpret these features to represent fronts between three adjacent isotopic provinces similar to what has been suggested for the Australian-Antarctic Discordance. The common DUPAL signature of MORB and OIB from the Indian province and the geochemistry of Gulf of Aden MORB and the Afar plume suggest that the source of this distinctive mantle component is deep and lies to the north of the province. This is also what the three-dimensional flow field computed by Behn et al. (2004) from shear-wave splitting shows with a major lower mantle upwelling radiating at the base of the asthenosphere under the Afar plume. Lower mantle gushing out from this source flows southward unimpeded along the Indian ridges, whereas it only reaches the South Atlantic ridge after first having been deflected under the deep roots of the South

  12. The Optical Gravitational Lensing Experiment. Gaia South Ecliptic Pole Field as Seen by OGLE-IV

    NASA Astrophysics Data System (ADS)

    Soszyński, I.; Udalski, A.; Poleski, R.; Kozłowski, S.; Wyrzykowski, Ł.; Pietrukowicz, P.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Ulaczyk, K.; Skowron, J.

    2012-09-01

    We present a comprehensive analysis of the Gaia South Ecliptic Pole (GSEP) field, 5.3 square degrees area around the South Ecliptic Pole on the outskirts of the LMC, based on the data collected during the fourth phase of the Optical Gravitational Lensing Experiment, OGLE-IV. The GSEP field will be observed during the commissioning phase of the ESA Gaia space mission for testing and calibrating the Gaia instruments. We provide the photometric maps of the GSEP region containing the mean VI photometry of all detected stellar objects and their equatorial coordinates. We show the quality and completeness of the OGLE-IV photometry and color-magnitude diagrams of this region. We conducted an extensive search for variable stars in the GSEP field leading to the discovery of 6789 variable stars. In this sample we found 132 classical Cepheids, 686 RR Lyr type stars, 2819 long-period, and 1377 eclipsing variables. Several objects deserving special attention were also selected, including a new classical Cepheid in a binary eclipsing system. To provide empirical data for the Gaia Science Alert system we also conducted a search for optical transients. We discovered two firm type Ia supernovae and nine additional supernova candidates. To facilitate future Gaia supernovae detections we prepared a list of more than 1900 galaxies to redshift about 0.1 located in the GSEP field. Finally, we present the results of astrometric study of the GSEP field. With the 26 months time base of the presented here OGLE-IV data, proper motions of stars could be detected with the accuracy reaching 2 mas/yr. Astrometry allowed to distinguish galactic foreground variable stars detected in the GSEP field from LMC objects and to discover about 50 high proper motion stars (proper motion ≥ 100 mas/yr). Among them three new nearby white dwarfs were found. All data presented in this paper are available to the astronomical community from the OGLE Internet archive.

  13. Temporal variability of soil water repellency in field conditions under humid Mediterranean climate (South of Spain)

    NASA Astrophysics Data System (ADS)

    Martinez-Murillo, Juan F.; Gabarron-Galeote, Miguel A.; Ruiz-Sinoga, Jose D.

    2013-04-01

    Soil water repellency (SWR) has become an important field of scientific study because of its effects on soil hydrological behavior, including reduced matrix infiltration, development of fingered flow in structural or textural preferential flow paths, irregular wetting fronts, and increased runoff generation and soil erosion. The aim of this study is to evaluate the temporal variability of SWR in Mediterranean rangeland under humid Mediterranean climatic conditions (Tª=14.5 °C; P=1,010 mm y-1) in South of Spain. Every month from September 2008 to May 2009 (rainy season), soil moisture and SWR was measured in field conditions by means of gravimetric method and Water Drop Penetration Test, respectively. The entire tests were performed in differente eco-geomorphological conditions in the experimental site: North and South aspect hillslopes and beneath shrub and bare soil in every of them. The results indicate that: i) climatic conditions seem to be more transcendent than the vegetal cover for explaining the temporal variability of SWR in field conditions; ii) thus, SWR appears to be controlled by the antecedent rainfall and soil moisture; iii) more severity SWR were observed in patches characterized by sandier soils and/or greater organic matter contents; and iv) the factor 'hillslope aspect' was not found very influential in the degree of SWR.

  14. A systematic search for z ≥ 5 active galactic nuclei in the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Weigel, Anna K.; Schawinski, Kevin; Treister, Ezequiel; Koss, Michael; Urry, C. Megan; Trakhtenbrot, Benny

    2015-01-01

    We investigate early black hole growth through the methodical search for z ≥ 5 AGN in the Chandra Deep Field South.We base our search on the Chandra 4-Ms data that should allow us to detect Compton-thin AGN with MBH >107 M⊙ accreting at Eddington ratios > 0.1.The Chandra Deep Field South contains over 600 z ≥ 5 Lyman Break Galaxies. These high-redshift galaxies are the progenitors of massive, local galaxies and based on lower redshift relations we would expect ~ 20 of them to host AGN.We combine the Chandra data with GOODS/ACS, CANDELS/WFC3 and Spitzer/IRAC data. After excluding clear low-redshift sources our sample consists of 58 high-redshift candidates. We use a range of redshift estimators including a photo-z code, stacking, colour criteria and the Lyman Break Technique. We also use the X-ray Hardness Ratio as additional information.The final z ≥ 5 candidates that remain after we combine our redshift tests, are likely to be low-redshift interlopers. We thus conclude that, contrary to our expectation of finding at least a few high-redshift AGN, the field does not contain any convincing z ≥ 5 AGN candidates.Our results place interesting constraints on early black hole growth and we discuss a range of possible explanations.

  15. Infrared Faint Radio Sources in the Extended Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Huynh, Minh T.

    2009-01-01

    Infrared-Faint Radio Sources (IFRSs) are a class of radio objects found in the Australia Telescope Large Area Survey (ATLAS) which have no observable counterpart in the Spitzer Wide-area Infrared Extragalactic Survey (SWIRE). The extended Chandra Deep Field South now has even deeper Spitzer imaging (3.6 to 70 micron) from a number of Legacy surveys. We report the detections of two IFRS sources in IRAC images. The non-detection of two other IFRSs allows us to constrain the source type. Detailed modeling of the SED of these objects shows that they are consistent with high redshift AGN (z > 2).

  16. The Field Operations and Early Results of the South China Sea Monsoon Experiment (SCSMEX)

    NASA Technical Reports Server (NTRS)

    Lau, K. M.; Ding, Yihui; Wang, Jough-Tai; Johnson, Richard; Keenan, Tom; Cifelli, Robert; Gerlach, John; Thiele, Otto; Rickenbach, Tom; Tsay, Si-Chee

    1999-01-01

    The South China Sea Monsoon Experiment (SCSMEX) is an international field experiment with the objective to better understand the key physical processes for the onset and evolution of the Asian summer monsoon in relation to fluctuation of the regional hydrologic cycle over Southeast Asian, southern East Asia, aiming at improving monsoon prediction. In this article, we present a description of the major meteorological observation platforms during the Intensive Observing Periods (IOP) of SCSMEX. We also provide highlights of early results and discussions of the role of SCSMEX in providing valuable in-situ data for calibration of satellite rainfall estimate from the Tropical Rainfall Measuring Mission (TRMM). Preliminary results indicate that there are distinctive stages in the onset of the South China Sea monsoon including possibly strong influences from extratropical systems as well as from convection over the Indian Ocean and the Bay of Bengal. There are some tantalizing evidence of complex interactions between the supercloud cluster development over the Indian Ocean, advancing southwest monsoon flow over the South China Sea, midlatitude disturbances and the western Pacific subtropical high, possibly contributing to the disastrous flood over Yangtze River Basin in China during June 1998.

  17. Balloon observations of ultra-low-frequency waves in the electric field above the South Pole

    SciTech Connect

    Liao, B.; Benbrrook, J.R.; Bering E.A. III; Byrne, G.J.; Theall, J.R. )

    1988-01-01

    The physics of ultra-low-frequency waves in the magnetosphere, near the cusp and in the polar cap, is important because this region is one where ultra-low-frequency wave energy from the magnetopause can most easily enter the magnetosphere. During the 1985-1986 South Pole balloon campaign, eight stratospheric balloon payloads were launched from Amundsen-Scott Station, South Geographic Pole, Antarctica, to record data on ultra-low-frequency waves. The payloads were instrumented with three-axis double-probe electric field detectors and X-ray scintillation counters. This paper concentrates on the third flight of this series, which was launched at 2205 universal time on 21 December 1985. Good data were received from the payload until the transmitter failed at 0342 universal time on 22 December. During most of the four hours that the balloon was afloat, an intense ultra-low-frequency wave event was in progress. The electric-field data from this period have been examined in detail and compared with magnetic field data, obtained with ground-based fluxgate and induction magnetometers to determine the characteristics of the waves. After float was reached, the electric-field data in figure 1 show large-amplitude, quasi-periodic fluctuations suggesting the presence of intense ultra-low-frequency wave activity. In conclusion, the electric-field signature observed from flight 3 appears to have been essentially an electrostatic event or possibly a short-wavelength hydromagnetic wave with a varying and interesting polarization character. The authors are continuing the analysis of the data to determine the source of the observed ultra-low-frequency waves.

  18. North-South Asymmetries in Earth's Magnetic Field. Effects on High-Latitude Geospace

    NASA Astrophysics Data System (ADS)

    Laundal, K. M.; Cnossen, I.; Milan, S. E.; Haaland, S. E.; Coxon, J.; Pedatella, N. M.; Förster, M.; Reistad, J. P.

    2017-03-01

    The solar-wind magnetosphere interaction primarily occurs at altitudes where the dipole component of Earth's magnetic field is dominating. The disturbances that are created in this interaction propagate along magnetic field lines and interact with the ionosphere-thermosphere system. At ionospheric altitudes, the Earth's field deviates significantly from a dipole. North-South asymmetries in the magnetic field imply that the magnetosphere-ionosphere-thermosphere (M-I-T) coupling is different in the two hemispheres. In this paper we review the primary differences in the magnetic field at polar latitudes, and the consequences that these have for the M-I-T coupling. We focus on two interhemispheric differences which are thought to have the strongest effects: 1) A difference in the offset between magnetic and geographic poles in the Northern and Southern Hemispheres, and 2) differences in the magnetic field strength at magnetically conjugate regions. These asymmetries lead to differences in plasma convection, neutral winds, total electron content, ion outflow, ionospheric currents and auroral precipitation.

  19. Traditional Geology Field Camp: A capstone course at South Dakota School of Mines and Technology (BHNSFS)

    NASA Astrophysics Data System (ADS)

    Uzunlar, N.; Lisenbee, A. L.

    2012-12-01

    The Black Hills Natural Sciences Field Station (BHNSFS) has provided field training in geology and geological engineering for more than 40 years, and since the 1980's as a consortium serving five schools with South Dakota School of Mines and Technology as the coordinator. The traditional summer geology field camp is a five week long, intense program aimed to prepare students for subsequent professional geologic experiences. It is delivered from two separate facilities, one in the Black Hills (South Dakota) from a beautiful log lodge along Sand Creek, in eastern Wyoming, and a second from the town of Taskesti along the North Anatolian fault approximately 200 km east of Istanbul, Turkey. At both locations, the courses maintain a strong emphasis on basic field applications, including the use of GPS as a mapping tool in most exercises. The preparation of well-written reports, based on field descriptions supplemented by research on the web or through published documents, is strongly emphasized. Projects at the Black Hills field camp includes mapping of Precambrian basement, Paleozoic stratigraphy, and Laramide Tertiary plutons and structural features as welll as post-Laramide,, faulted continental strata. The popular Taskesti field camp utilizes the diverse geology of the Tethyan realm, as well as the culture and history, of central Turkey (Anatolia). The course is based at a Turkish Government Earthquake Research Center facility along the North Anatolian fault. Students examine and map selected locations across the Izmir-Ankara suture including: 1) Deformed Cretaceous and Tertiary carbonate and clastic strata of the Sakarya micro-continent in a fore-arc basin; 2) Marble and skarn surrounding Eocene, subduction-related granite intruded into a passive margin sequence in the Sivrihisar region of central Anatolia; 3) Faulted and folded Neogene strata in the northern flank of the post-Tethyan, Haymana Basin and the contrasting terrains across the North Anatolian fault (J

  20. VizieR Online Data Catalog: Spitzer-CANDELS catalog within 5 deep fields (Ashby+, 2015)

    NASA Astrophysics Data System (ADS)

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Dunlop, J. S.; Egami, E.; Faber, S. M.; Ferguson, H. C.; Grogin, N. A.; Hora, J. L.; Huang, J.-S.; Koekemoer, A. M.; Labbe, I.; Wang, Z.

    2015-08-01

    We chose to locate S-CANDELS inside the wider and shallower fields already covered by Spitzer Extended Deep Survey (SEDS), in regions that enjoy deep optical and NIR imaging from HST/CANDELS. These S-CANDELS fields are thus the Extended GOODS-south (aka the GEMS field, hereafter ECDFS; Rix et al. 2004ApJS..152..163R; Castellano et al. 2010A&A...511A..20C), the Extended GOODS-north (HDFN; Giavalisco et al. 2004, II/261; Wang et al. 2010, J/ApJS/187/251; Hathi et al. 2012ApJ...757...43H; Lin et al. 2012ApJ...756...71L), the UKIDSS UDS (aka the Subaru/XMM Deep Field, Ouchi et al. 2001ApJ...558L..83O; Lawrence et al. 2007, II/319), a narrow field within the EGS (Davis et al. 2007ApJ...660L...1D; Bielby et al. 2012A&A...545A..23B), and a strip within the UltraVista deep survey of the larger COSMOS field (Scoville et al. 2007ApJS..172...38S; McCracken et al. 2012, J/A+A/544/A156). The S-CANDELS observing strategy was designed to maximize the area covered to full depth within the CANDELS area. Each field was visited twice with six months separating the two visits. Table 1 lists the epochs for each field. All of the IRAC full-depth coverage is within the SEDS area (Ashby et al. 2013, J/ApJ/769/80), and almost all is within the area covered by HST for CANDELS. (6 data files).

  1. The oral susceptibility of South African field populations of Culicoides to African horse sickness virus.

    PubMed

    Venter, G J; Wright, I M; Van Der Linde, T C; Paweska, J T

    2009-12-01

    Twenty-two isolates of African horse sickness virus (AHSV), representing its distinct serotypes, geographical and historical origins, were fed to three populations of South African livestock-associated Culicoides spp. (Diptera, Ceratopogonidae). Infective blood meals included 12 recent isolates, nine historical reference strains and one live attenuated vaccine strain serotype 7 (AHSV-7) of the virus. Field-collected midges were fed through a chicken-skin membrane on sheep blood spiked with one of the viruses, which concentrations ranged from 5.4 to 8.8 log(10)TCID(50)/mL of blood. After 10 days incubation at 23.5 degrees C, AHSV was isolated from 11 Culicoides species. Standard in vitro passaging of AHSV-7, used for the preparation of live attenuated vaccine, did not reduce its ability to infect Culicoides species. Virus recovery rates in orally infected Culicoides midges differed significantly between species and populations, serotypes, isolates and seasons. Significant variations in oral susceptibility recorded in this study emphasize a complex inter-relationship between virus and vector, which is further influenced by multiple intrinsic and extrinsic factors. As it is not possible to standardize all these factors under laboratory conditions, conclusive assessment of the role of field-collected Culicoides midges in the transmission of orbiviruses remains problematic. Nevertheless, results of this study suggest the potential for multi-vector transmission of AHSV virus in South Africa.

  2. University of South Florida Field Test of the Michigan State University Protocol Materials on Learning. Final Report.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Coll. of Education.

    The Michigan State University protocol materials on learning were field-tested at the University of South Florida (U.S.F.). The field-testing at U.S.F. did not occur under controlled, experimental conditions. The information needs of the protocol developers were balanced with the instructional obligations of the instructors and the educational…

  3. North south asymmetry in the photospheric and coronal magnetic fields observed by different instruments

    NASA Astrophysics Data System (ADS)

    Virtanen, Ilpo; Mursula, Kalevi

    2015-04-01

    Several recent studies have shown that the solar and heliospheric magnetic fields are north-south asymmetric. The southward shift of the Heliospheric current sheet (HCS) (the so-called bashful ballerina phenomenon) is a persistent pattern, which occurs typically for about three years during the late declining phase of solar cycle. We study here the hemispherical asymmetry in the photospheric and coronal magnetic fields using Wilcox Solar Observatory (WSO), Mount Wilson, Kitt Peak, Solis, SOHO/MDI and SDO/HMI measurements of the photospheric magnetic field since the 1970s and the potential field source surface (PFSS) model.Multipole analysis of the photospheric magnetic field has shown that the bashful ballerina phenomenon is a consequence of g20 quadrupole term, which is oppositely signed to the dipole moment. We find that, at least during the four recent solar cycles, the g20 reflects the larger magnitude of the southern polar field during a few years in the declining phase of the cycle. Although the overall magnetic activity during the full solar cycle is not very different in the two hemispheres, the temporal distribution of activity is different, contributing to the asymmetry. The used data sets are in general in a good agreement with each other, but there are some significant deviations, especially in WSO data. Also, the data from Kitt Peak 512 channel magnetograph is known to suffer from zero level errors.We also note that the lowest harmonic coefficients do not scale with the overall magnitude in photospheric synoptic magnetic maps. Scaling factors based on histogram techniques can be as large as 10 (from Wilcox to HMI), but the corresponding difference in dipole strength is typically less than two. This is because the polar field has a dominant contribution to the dipole and quadrupole components. This should be noted, e.g., when using synoptic maps as input for coronal models.

  4. Secondary natural gas recovery in mature fluvial sandstone reservoirs, Frio Formation, Agua Dulce Field, South Texas

    SciTech Connect

    Ambrose, W.A.; Levey, R.A. ); Vidal, J.M. ); Sippel, M.A. ); Ballard, J.R. ); Coover, D.M. Jr. ); Bloxsom, W.E. )

    1993-09-01

    An approach that integrates detailed geologic, engineering, and petrophysical analyses combined with improved well-log analytical techniques can be used by independent oil and gas companies of successful infield exploration in mature Gulf Coast fields that larger companies may consider uneconomic. In a secondary gas recovery project conducted by the Bureau of Economic Geology and funded by the Gas Research Institute and the U.S. Department of Energy, a potential incremental natural gas resource of 7.7 bcf, of which 4.0 bcf may be technically recoverable, was identified in a 490-ac lease in Agua Dulce field. Five wells in this lease had previously produced 13.7 bcf from Frio reservoirs at depths of 4600-6200 ft. The pay zones occur in heterogeneous fluvial sandstones offset by faults associated with the Vicksburg fault zone. The compartments may each contain up to 1.0 bcf of gas resources with estimates based on previous completions and the recent infield drilling experience of Pintas Creek Oil Company. Uncontacted gas resources occur in thin (typically less than 10 ft) bypassed zones that can be identified through a computed log evaluation that integrates open-hole logs, wireline pressure tests, fluid samples, and cores. At Agua Dulce field, such analysis identified at 4-ft bypassed zone uphole from previously produced reservoirs. This reservoir contained original reservoir pressure and flowed at rates exceeding 1 mmcf/d. The expected ultimate recovery is 0.4 bcf. Methodologies developed in the evaluation of Agua Dulce field can be successfully applied to other mature gas fields in the south Texas Gulf Coast. For example, Stratton and McFaddin are two fields in which the secondary gas recovery project has demonstrated the existence of thin, potentially bypassed zones that can yield significant incremental gas resources, extending the economic life of these fields.

  5. The Archeomagnetic field in South America: Present status and perspectives (Invited)

    NASA Astrophysics Data System (ADS)

    Hartmann, G. A.; Trindade, R. I.; Gallet, Y.; Poletti, W.; Begnini, G. S.; Genevey, A.; Legoff, M.

    2013-12-01

    Geomagnetic field variations over decadal to millennial timescales can be determined from direct (i.e. observatory) and indirect (e.g. from archeological artifacts and volcanics) sources. Before the observatory era, the recovery of these variations is however still strongly penalized by the very uneven both geographical and temporal distributions of the available archeo/paleomagnetic dataset. In particular, the southern hemisphere contributes with only ~3% of the global archeomagnetic database. Moreover, most of these data present restrictions due to their poor experimental reliability and to the lack of good age control. Therefore, new intensity and directional data from the southern hemisphere are strongly requested for the next generation of archeomagnetic field models. In this presentation, we will report on intensity and inclination results obtained from different regions in Brazil. A collection of twenty-three site-mean archeointensity data were obtained by our team from architectural brick fragments dated to the past 500 years from Northeast and Southeast Brazil. This dataset was complemented by a series of new results from South Brazil. In addition, we also obtained inclination data, after reconstructing the firing position of the ancient bricks from modern analogs of historical brickyards. Thirteen site-mean inclination results dated to between 1790 AD and 1950 AD and five inclination results spanning the 1590-1920 AD time interval were so determined from Southeast and Northeast Brazil, respectively. Altogether, our data, which are geographically distributed over more than 20 degrees in latitude, allow us to discuss the large-scale influence in Brazil and South America of non-dipolar features of the geomagnetic field during the past few centuries.

  6. South American oil and gas fields: Reasons for their presence and distribution

    SciTech Connect

    Pratsch, J.C. )

    1993-02-01

    South American oil and gas fields occur in geographic clusters. Their concentration in relatively small producing areas depends on the present location of the hydrocarbon generating depocenter and results from the basinal oil and gas migration history. By defining both, existing field locations can be explained and new field occurrences can be predicted, including those in overthrust plays. One-and two-stage hydrocarbon migration processes exist: In one-stage migration oil and gas migrate directly from the generating source beds into reservoirs, like in Maturin Basin or Maranon Basin fields. In two-stage migration oil and gas first migrate into a primary reservoir level, from there during a second migration phase into a (commonly younger) secondary reservoir level. Here, the original source beds may be over-mature or even metamorphosed today; examples here are the Maturin, Llanos and Oriente Basins, possibly offshore Trinidad. Definition of generating depocenters is the task of regional exploration. Oil and gas migration analysis is one result of semi-detailed structural mapping using gravity, magnetic, seismic reflection and geochemical data. Oil and gas exploration in two-stage migration basins are especially challenging, like in the Austral Basin of southern Argentina and Chile or possibly in the Parana Basin.

  7. Hydrologic reconnaissance of the Kolob, Alton, and Kaiparowits Plateau coal fields, south-central Utah

    USGS Publications Warehouse

    Plantz, Gerald G.

    1985-01-01

    The study area in south-central Utah (fig. 1) is noted for its large coal reserves in the Alton, Kolob, and Kaiparowits Plateau coal fields. The area also is noted for its scenic beauty and general scarcity of water. Although there has been very little development of the coal resources through 1983, there is a potential for large-scale development with both surface- and underground-mining methods. Mining of coal could have significant effects on the quantity and quality of the water resources. The purpose of this atlas is to define the surface- and ground-water resources of the area and to identify the potential effects on these resources by coal mining.

  8. Sandy beach molluscs as possible bio-indicators of metal pollution 1. field survey. [South Africa

    SciTech Connect

    Watling, H.R.; Watling, R.J.

    1983-09-01

    A great variety of molluscs occur around the South African coast, extending as it does from the sub-tropical environment of Natal to the temperate environment of the Cape. The potential of many of these molluscs as bio-indicators has been discussed in general terms on the basis of the reported use of related species (DARRACOTT and WATLING 1975) and certain of these, among them the bivalve Donax serra and gastropod Bullia rhodostoma, have been included in the national marine pollution monitoring program. The aims of this preliminary investigation are: to determine the metal concentrations in D. serra and B. rhodostoma growing along a 500 km stretch of the southern African coast, supplementing data from sediment and water sampling surveys of the same region; and to determine in laboratory studies whether these molluscs accumulate metals, thus meeting some at least of the criteria for monitoring organisms. The field survey data are presented in this paper.

  9. South Baltic representative coastal field surveys, including monitoring at the Coastal Research Station in Lubiatowo, Poland

    NASA Astrophysics Data System (ADS)

    Ostrowski, Rafał; Schönhofer, Jan; Szmytkiewicz, Piotr

    2016-10-01

    The paper contains a brief description of selected investigations carried out in the south Baltic coastal zone, with the particular focus on the history and recent activities conducted at the Coastal Research Station in Lubiatowo (CRS Lubiatowo), Poland. These activities comprise field investigations of nearshore hydrodynamic, lithodynamic, and morphodynamic processes. The study area is a sandy multi-bar shore with a mild slope, much exposed to the impact of waves approaching from NW-NE sector. The shore has a dissipative character which means that the wave energy is subject to gradual dissipation in the nearshore zone and only a small part of this energy is reflected by the shore. Due to the big wind fetch in N-NNE direction, the location of CRS Lubiatowo is favourable to registration of the maximum values of parameters of hydrodynamic and morphodynamic processes which occur in the Baltic during extreme storms.

  10. Trends of Abutment-Scour Prediction Equations Applied to 144 Field Sites in South Carolina

    USGS Publications Warehouse

    Benedict, Stephen T.; Deshpande, Nikhil; Aziz, Nadim M.; Conrads, Paul A.

    2006-01-01

    The U.S. Geological Survey conducted a study in cooperation with the Federal Highway Administration in which predicted abutment-scour depths computed with selected predictive equations were compared with field measurements of abutment-scour depth made at 144 bridges in South Carolina. The assessment used five equations published in the Fourth Edition of 'Evaluating Scour at Bridges,' (Hydraulic Engineering Circular 18), including the original Froehlich, the modified Froehlich, the Sturm, the Maryland, and the HIRE equations. An additional unpublished equation also was assessed. Comparisons between predicted and observed scour depths are intended to illustrate general trends and order-of-magnitude differences for the prediction equations. Field measurements were taken during non-flood conditions when the hydraulic conditions that caused the scour generally are unknown. The predicted scour depths are based on hydraulic conditions associated with the 100-year flow at all sites and the flood of record for 35 sites. Comparisons showed that predicted scour depths frequently overpredict observed scour and at times were excessive. The comparison also showed that underprediction occurred, but with less frequency. The performance of these equations indicates that they are poor predictors of abutment-scour depth in South Carolina, and it is probable that poor performance will occur when the equations are applied in other geographic regions. Extensive data and graphs used to compare predicted and observed scour depths in this study were compiled into spreadsheets and are included in digital format with this report. In addition to the equation-comparison data, Water-Surface Profile Model tube-velocity data, soil-boring data, and selected abutment-scour data are included in digital format with this report. The digital database was developed as a resource for future researchers and is especially valuable for evaluating the reasonableness of future equations that may be developed.

  11. The Chandra Deep Field South as a test case for Global Multi Conjugate Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Portaluri, E.; Viotto, V.; Ragazzoni, R.; Gullieuszik, M.; Bergomi, M.; Greggio, D.; Biondi, F.; Dima, M.; Magrin, D.; Farinato, J.

    2017-04-01

    The era of the next generation of giant telescopes requires not only the advent of new technologies but also the development of novel methods, in order to exploit fully the extraordinary potential they are built for. Global Multi Conjugate Adaptive Optics (GMCAO) pursues this approach, with the goal of achieving good performance over a field of view of a few arcmin and an increase in sky coverage. In this article, we show the gain offered by this technique to an astrophysical application, such as the photometric survey strategy applied to the Chandra Deep Field South as a case study. We simulated a close-to-real observation of a 500 × 500 arcsec2 extragalactic deep field with a 40-m class telescope that implements GMCAO. We analysed mock K-band images of 6000 high-redshift (up to z = 2.75) galaxies therein as if they were real to recover the initial input parameters. We attained 94.5 per cent completeness for source detection with SEXTRACTOR. We also measured the morphological parameters of all the sources with the two-dimensional fitting tools GALFIT. The agreement we found between recovered and intrinsic parameters demonstrates GMCAO as a reliable approach to assist extremely large telescope (ELT) observations of extragalactic interest.

  12. STAR FORMATION IN THE CHANDRA DEEP FIELD SOUTH: OBSERVATIONS CONFRONT SIMULATIONS

    SciTech Connect

    Damen, Maaike; Franx, Marijn; Foerster Schreiber, Natascha M.; Labbe, Ivo; Toft, Sune; Van Dokkum, Pieter G.; Wuyts, Stijn

    2009-11-01

    We investigate the star formation history of the universe using FIREWORKS, a multiwavelength survey of the Chandra Deep Field South. We study the evolution of the specific star formation rate (sSFR) with redshift in different mass bins from z = 0 to z approx 3. We find that the sSFR increases with redshift for all masses. The logarithmic increase of the sSFR with redshift is nearly independent of mass, but this cannot yet be verified at the lowest-mass bins at z>0.8, due to incompleteness. We convert the sSFRs to a dimensionless growth rate to facilitate a comparison with a semianalytic galaxy formation model that was implemented on the Millennium Simulation. The model predicts that the growth rates and sSFRs increase similarly with redshift for all masses, consistent with the observations. However, we find that for all masses, the inferred observed growth rates increase more rapidly with redshift than the model predictions. We discuss several possible causes for this discrepancy, ranging from field-to-field variance, conversions to SFR, and shape of the initial mass function. We find that none of these can solve the discrepancy completely. We conclude that the models need to be adapted to produce the steep increase in growth rate between redshift z = 0 and z = 1.

  13. Turtle Bayou 1936-1983: case history of a major gas field in south Louisiana

    SciTech Connect

    Cronquist, C.

    1984-11-01

    Turtle Bayou field, located in the middle Miocene trend in south Louisiana, is nearing the end of a productive life spanning more than 30 years. Discovered by Shell Oil Co. in 1949 after unsuccessful attempts by two other companies, the field is a typical, low-relief, moderately faulted U.S. Gulf Coast structure, probably associated with deep salt movement. The productive interval includes 22 separate gas-bearing sands in a regressive sequence of sands and shales from approximately 6,500 to 12,000 ft (1980 to 3660 m). Now estimated to have contained about 1.2 trillion scf (34 X 10/sup 9/ std m/sup 3/) of gas in place, cumulative production through 1982 was 702 billion scf (20 X 10/sup 9/ std m/sup 3/). Cumulative condensate/gas ration (CGR) has been 20 bbl/MMcf (110 X 10/sup -6/ m/sup 3//m/sup 3/. Recovery mechanisms in individual reservoirs include strong bottomwater drive, partial edgewater drive, and pressure depletion. Recovery efficiencies in major reservoirs range form 40 to 83% of original gas in place (OGIP). On decline since 1973, it is anticipated the field will be essentially depleted in the next 5 years.

  14. The Spitzer-IRAC/MIPS Extragalactic Survey (SIMES) in the South Ecliptic Pole Field

    NASA Astrophysics Data System (ADS)

    Baronchelli, I.; Scarlata, C.; Rodighiero, G.; Franceschini, A.; Capak, P. L.; Mei, S.; Vaccari, M.; Marchetti, L.; Hibon, P.; Sedgwick, C.; Pearson, C.; Serjeant, S.; Menéndez-Delmestre, K.; Salvato, M.; Malkan, M.; Teplitz, H. I.; Hayes, M.; Colbert, J.; Papovich, C.; Devlin, M.; Kovacs, A.; Scott, K. S.; Surace, J.; Kirkpatrick, J. D.; Atek, H.; Urrutia, T.; Scoville, N. Z.; Takeuchi, T. T.

    2016-03-01

    We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field. The large area covered (7.7 deg2), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Herschel, Akari, and GALEX, make the SIMES field ideal for extragalactic studies. The elongated geometry of the SIMES area (≈4:1), allowing for significant cosmic variance reduction, further improves the quality of statistical studies in this field. Here we present the reduction and photometric measurements of the Spitzer/IRAC data. The survey reaches depths of 1.93 and 1.75 μJy (1σ) at 3.6 and 4.5 μm, respectively. We discuss the multiwavelength IRAC-based catalog, completed with optical, mid-, and far-IR observations. We detect 341,000 sources with {F}3.6μ {{m}}≥slant 3σ . Of these, 10% have an associated 24 μm counterpart, while 2.7% have an associated SPIRE source. We release the catalog through the NASA/IPAC Infrared Science Archive. Two scientific applications of these IRAC data are presented in this paper. First, we compute integral number counts at 3.6 μm. Second, we use the [3.6]-[4.5] color index to identify galaxy clusters at z > 1.3. We select 27 clusters in the full area, a result consistent with previous studies at similar depth.

  15. EVALUATION OF THE FLOOD POTENTIAL OF THE SOUTH HOUSE (BLINEBRY) FIELD, LEA COUNTY, NEW MEXICO

    SciTech Connect

    L. Stephen Melzer

    2000-12-01

    /11 respectively. Production of oil and gas has been established with several months of production now available to make a reserve analysis. Production histories and reserves estimation are provided. An assessment of the flood potential for the South House project area has been completed with work concentrated on South House rock property and pay thickness characterization and analog studies. For the analogs, the North Robertson area, located twenty miles to the northeast, and the Teague Field, located 20 miles to the south, have been utilized due to their readily available database and previous waterflood studies. The South House area does appear to merit further examination as the rock quality compares favorably with both analog Fields; however, current well spacings of 40-acres will provide only marginal economics based upon $23.00/barrel oil prices. Permeability and porosity relationships are provided as a conditional demonstration that rock quality may be sufficient for successful waterflooding of the project area. Further rock property work and pay continuity studies are recommended.

  16. Present-day stress field on the South American slab underneath the Sandwich Plate (Southern Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Giner-Robles, J. L.; Pérez-López, R.; Álvarez-Gómez, J. A.; Martínez-Díaz, J. J.; Rodríguez-Pascua, M. A.

    2009-04-01

    This work confirms the present-day principal stress orientation on the South Sandwich Plate (SSP) from the analysis of 331 earthquake focal mechanisms (Harvard catalog, HCMT). Principal stress orientation was deduced from earthquake focal mechanisms, examined by fault population analysis methods. The SSP plate is composed by oceanic crust limits an elliptical trench to the east (South Sandwich Trench), a ridge to the west and transforms faults towards the northern and southern boundaries. Within the trench region, the maximum horizontal shortening direction (SHMAX) rotates in trend in a clockwise direction, from NNE, in the northern boundary, to SSE in the southern boundary. Therefore, and keeping in mind the gradual rotation of SHMAX along the trench, three different areas were defined according to the prevailing focal mechanism type: (1) the North Zone, with SHMAX oriented N060°E and reverse and strike-slip focal mechanisms; (2) the Central Zone, with only reverse focal mechanism and SHMAX striking N080°E; (3) the South Zone, with SHMAX oriented N110°E and reverse and strike-slip focal geometry. Furthermore, the accommodation of the strain field in the Northern Zone of the South Sandwich Plate generates a subduction decoupling of the slab at, approximately, 70 km depth. In contrast, the South Zone slab exhibits a gradual stress and strain magnitude decreasing in depth. Finally, we define a sinistral strike-slip parallel to the southern boundary between the South Sandwich Plate and the Antarctic Plate, the South Sandwich Fault Zone.

  17. A DETERMINATION OF THE NORTH–SOUTH HELIOSPHERIC MAGNETIC FIELD COMPONENT FROM INNER CORONA CLOSED-LOOP PROPAGATION

    SciTech Connect

    Jackson, B. V.; Hick, P. P.; Buffington, A.; Yu, H.-S.; Bisi, M. M.; Tokumaru, M.; Zhao, X. E-mail: pphick@ucsd.edu E-mail: hsyu@ucsd.edu

    2015-04-10

    A component of the magnetic field measured in situ near the Earth in the solar wind is present from north–south fields from the low solar corona. Using the Current-sheet Source Surface model, these fields can be extrapolated upward from near the solar surface to 1 AU. Global velocities inferred from a combination of interplanetary scintillation observations matched to in situ velocities and densities provide the extrapolation to 1 AU assuming mass and mass flux conservation. The north–south field component is compared with the same ACE in situ magnetic field component—the Normal (Radial Tangential Normal) Bn coordinate—for three years throughout the solar minimum of the current solar cycle. We find a significant positive correlation throughout this period between this method of determining the Bn field compared with in situ measurements. Given this result from a study during the latest solar minimum, this indicates that a small fraction of the low-coronal Bn component flux regularly escapes from closed field regions. The prospects for Space Weather, where the knowledge of a Bz field at Earth is important for its geomagnetic field effects, is also now enhanced. This is because the Bn field provides the major portion of the Geocentric Solar Magnetospheric Bz field coordinate that couples most closely to the Earth’s geomagnetic field.

  18. The systematic search for z ≳ 5 active galactic nuclei in the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Weigel, Anna K.; Schawinski, Kevin; Treister, Ezequiel; Urry, C. Megan; Koss, Michael; Trakhtenbrot, Benny

    2015-04-01

    We investigate early black hole (BH) growth through the methodical search for z ≳ 5 active galactic nuclei (AGN) in the Chandra Deep Field South. We base our search on the Chandra 4-Ms data with flux limits of 9.1 × 10-18 (soft, 0.5-2 keV) and 5.5 × 10-17 erg s-1 cm-2 (hard, 2-8 keV). At z ˜ 5, this corresponds to luminosities as low as ˜1042 (˜1043) erg s-1 in the soft (hard) band and should allow us to detect Compton-thin AGN with MBH > 107 M⊙ and Eddington ratios >0.1. Our field (0.03 deg2) contains over 600z ˜ 5 Lyman Break Galaxies. Based on lower redshift relations, we would expect ˜20 of them to host AGN. After combining the Chandra data with Great Observatories Origins Deep Survey (GOODS)/Advanced Camera for Surveys (ACS), CANDELS/Wide Field Camera 3 and Spitzer/Infrared Array Camera data, the sample consists of 58 high-redshift candidates. We run a photometric redshift code, stack the GOODS/ACS data, apply colour criteria and the Lyman Break Technique and use the X-ray Hardness Ratio. We combine our tests and using additional data find that all sources are most likely at low redshift. We also find five X-ray sources without a counterpart in the optical or infrared which might be spurious detections. We conclude that our field does not contain any convincing z ≳ 5 AGN. Explanations for this result include a low BH occupation fraction, a low AGN fraction, short, super-Eddington growth modes, BH growth through BH-BH mergers or in optically faint galaxies. By searching for z ≳ 5 AGN, we are setting the foundation for constraining early BH growth and seed formation scenarios.

  19. Definition of reservoir configuration in ancient glacial environment: case history from Rima field, south Oman

    SciTech Connect

    Penneycard, A.J.

    1986-05-01

    The Al Khlata Formation (Permian-Carboniferous) is an important reservoir unit of the Eastern Flank province of South Oman. The formation consists of an unusual series of glacial sand, silt, shale, and diamictite exhibiting such gross heterogeneity that conventional correlation techniques are ineffective. A threefold palynologic subdivision has been developed, which has allowed the recognition of a number of genetically distinct units. Major periods of erosion separate the units, erosive processes dominating the 20-40 million year period during which the Al Khlata accumulated. Deposition occurred in a sequence of deep valleys cut into the early Al Khlata and underlying Haima (Cambrian-Ordovician) reservoirs. The extent of these deposits is controlled by the morphology of these incisive valleys. A case history of the large Rima field illustrates the use of palynology in unraveling the temporal and spatial relationships of the individual Al Khlata and Haima units. The resultant reservoir-geologic model of this internally complex fields has enabled more confident assessment of variations in well performance with reservoir type, and has guided plans for future offtake levels and overall development planning.

  20. BLAST OBSERVATIONS OF THE SOUTH ECLIPTIC POLE FIELD: NUMBER COUNTS AND SOURCE CATALOGS

    SciTech Connect

    Valiante, Elisabetta; Braglia, Filiberto G.; Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Scott, Douglas; Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Pascale, Enzo; Bock, James J.; Devlin, Mark J.; Klein, Jeff; Gundersen, Joshua O.; Hughes, David H.; Netterfield, Calvin B.; Olmi, Luca; Patanchon, Guillaume; Rex, Marie

    2010-12-15

    We present results from a survey carried out by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) on a 9 deg{sup 2} field near the South Ecliptic Pole at 250, 350, and 500 {mu}m. The median 1{sigma} depths of the maps are 36.0, 26.4, and 18.4 mJy, respectively. We apply a statistical method to estimate submillimeter galaxy number counts and find that they are in agreement with other measurements made with the same instrument and with the more recent results from Herschel/SPIRE. Thanks to the large field observed, the new measurements give additional constraints on the bright end of the counts. We identify 132, 89, and 61 sources with S/N {>=}4 at 250, 350, 500 {mu}m, respectively and provide a multi-wavelength combined catalog of 232 sources with a significance {>=}4{sigma} in at least one BLAST band. The new BLAST maps and catalogs are available publicly at http://blastexperiment.info.

  1. Hydrogeology and simulation of ground-water flow at the South Well Field, Columbus, Ohio

    USGS Publications Warehouse

    Cunningham, W.L.; Bair, E.S.; Yost, W.P.

    1996-01-01

    The City of Columbus, Ohio, operates four radial collector wells in southern Franklin County. The 'South Well Field' is completed in permeable outwash and ice-contact deposits, upon which flow the Scioto River and Big Walnut Creek. The wells are designed to yield approximately 42 million gallons per day; part of that yield results from induced infiltration of surface water from the Scioto River and Big Walnut Creek. The well field supplied up to 30 percent of the water supply of southern Columbus and its suburbs in 1991. This report describes the hydrogeology of southern Franklin County and a tran sient three-dimensional, numerical ground-water- flow model of the South Well Field. The primary source of ground water in the study area is the glacial drift aquifer. The glacial drift is composed of sand, gravel, and clay depos ited during the Illinoian and Wisconsinan glaciations. In general, thick deposits of till containing lenses of sand and gravel dominate the drift in the area west of the Scioto River. The thickest and most productive parts of the glacial drift aquifer are in the buried valleys in the central and eastern parts of the study area underlying the Scioto River and Big Walnut Creek. Horizontal hydraulic conductivity of the glacial drift aquifer differs spa tially and ranges from 30 to 375 feet per day. The specific yield ranges from 0.12 to 0.30. The secondary source of ground water within the study area is the underlying carbonate bedrock aquifer, which consists of Silurian and Devonian limestones, dolomites, and shales. The horizontal hydraulic conductivity of the carbonate bedrock aquifer ranges from 10 to 15 feet per day. The storage coefficient is about 0.0002. The ground-water-flow system in the South Well Field area is recharged by precipitation, regional ground-water flow, and induced stream infiltration. Yearly recharge rates varied spatially and ranged from 4.0 to 12.0 inches. The three-dimensional, ground-water-flow model was constructed by

  2. Genotypic diversity in Babesia bovis field isolates and vaccine strains from South Africa.

    PubMed

    Combrink, M P; Troskie, P C; Pienaar, R; Latif, A A; Mans, B J

    2014-01-31

    Genotypic diversity in Babesia bovis (cause of Asiatic redwater in cattle) vaccine strains and field isolates from South Africa were investigated using the Bv80 gene as well as microsatellites. The S11 vaccine strain possessed both A and B alleles of the Bv80 gene, as well as genotypic diversity within each allele type as defined by repeat variation resulting in different amplicon sizes. Rapid serial passage of vaccine strain from passage S10 to S24 resulted in loss of genotypic diversity that yielded a single allele A genotype with an amplicon size of 558 bp. This suggested that clonal selection occurred during rapid passaging. Extensive genotypic diversity exists in 44 field isolates characterized with both Bv80 A and B alleles, but can be readily distinguished from the S24 vaccine strain using either the Bv80 allele specific PCR assays or using multi-locus micro-satellite typing. This indicated that no recent documented clinical cases of Asiatic redwater were caused by the reversion to virulence of the current vaccine strain.

  3. Optical Survey with KMTNet for Dusty Star-Forming Galaxies in the Akari Deep Field South

    NASA Astrophysics Data System (ADS)

    Jeong, Woong-Seob; Ko, Kyeongyeon; Kim, Minjin; Ko, Jongwan; Kim, Sam; Pyo, Jeonghyun; Kim, Seong Jin; Kim, Taehyun; Seo, Hyun Jong; Park, Won-Kee; Park, Sung-Joon; Kim, Min Gyu; Kim, Dong Jin; Cha, Sang-Mok; Lee, Yongseok; Lee, Chung-Uk; Kim, Seung-Lee; Matsuura, Shuji; Pearson, Chris; Matsuhara, Hideo

    2016-10-01

    We present an optical imaging survey of AKARI Deep Field South (ADF-S) using the Korea Microlensing Telescope Network (KMTNet), to find optical counterparts of dusty star-forming galaxies. The ADF-S is a deep far-infrared imaging survey region with AKARI covering around 12 deg^2, where the deep optical imaging data are not yet available. By utilizing the wide-field capability of the KMTNet telescopes (˜4 deg^2), we obtain optical images in B, R and I bands for three regions. The target depth of images in B, R and I bands is ˜24 mag (AB) at 5σ, which enables us to detect most dusty star-forming galaxies discovered by AKARI in the ADF-S. Those optical datasets will be helpful to constrain optical spectral energy distributions as well as to identify rare types of dusty star-forming galaxies such as dust-obscured galaxy, sub-millimeter galaxy at high redshift.}

  4. Deep Medium-Band Subaru Imaging of the MUSYC Extended Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Urry, C. Megan; Cardamone, C.; van Dokkum, P.; Gawiser, E.; Brammer, G.; Taylor, N.; Treister, E.; Taniguchi, Y.; Sasaki, S.; Virani, S.; Kriek, M.

    2009-01-01

    We report on deep medium-band imaging with the Subaru telescope, in 18 filters from 427 nm to 856 nm, of the MUSYC survey field in the Extended Chandra Deep Field South. We detect 80,000 galaxies to equivalent magnitude R 27 mag, of which approximately 1,000 are X-ray-luminous AGN observed with Chandra and XMM. Combining the Subaru data with optical and IR data (in U,U38,B,V,R,I,z,J,K) we obtain photometric redshifts using EAZY, a fast public photometric redshift code, in the range 0

  5. Trace Contraband Detection Field-Test by the South Texas Specialized Crimes and Narcotics Task Force

    SciTech Connect

    Hannum, David W.; Shannon, Gary W.

    2006-04-01

    This report describes the collaboration between the South Texas Specialized Crimes and Narcotics Task Force (STSCNTF) and Sandia National Laboratories (SNL) in a field test that provided prototype hand-held trace detection technology for use in counter-drug operations. The National Institute of Justice (NIJ)/National Law Enforcement and Corrections Technology Center (NLECTC)/Border Research and Technology Center (BRTC) was contacted by STSCNTF for assistance in obtaining cutting-edge technology. The BRTC created a pilot project for Sandia National Laboratories (SNL) and the STSCNTF for the use of SNL’s Hound, a hand-held sample collection and preconcentration system that, when combined with a commercial chemical detector, can be used for the trace detection of illicit drugs and explosives. The STSCNTF operates in an area of high narcotics trafficking where methods of concealment make the detection of narcotics challenging. Sandia National Laboratories’ (SNL) Contraband Detection Department personnel provided the Hound system hardware and operational training. The Hound system combines the GE VaporTracer2, a hand-held commercial chemical detector, with an SNL-developed sample collection and preconcentration system. The South Texas Task force reported a variety of successes, including identification of a major shipment of methamphetamines, the discovery of hidden compartments in vehicles that contained illegal drugs and currency used in drug deals, and the identification of a suspect in a nightclub shooting. The main advantage of the hand-held trace detection unit is its ability to quickly identify the type of chemical (drugs or explosives) without a long lag time for laboratory analysis, which is the most common analysis method for current law enforcement procedures.

  6. The South American Meridional B-field Array (SAMBA) and Pc4-5 Wave Studies

    NASA Astrophysics Data System (ADS)

    Sterner, Lt. Nathan; Zesta, Eftyhia; Boudouridis, Athanasios; Moldwin, Mark; Yizengaw, Endawoke; Chi, Peter

    The Antarctic continent, the only landmass in the southern polar region, offers the unique opportunity for observations that geomagnetically range from polar latitudes to well into the inner magnetosphere, thus enabling conjugate observations in a wide range of geomagnetic lat-itudes. The SAMBA (South American Meridional B-field Array) chain is a meridional chain of 12 magnetometers, 11 of them at L=1.1 to L=2.5 along the coast of Chile and in the Antarc-tica peninsula, and one auroral station along the same meridian. SAMBA is conjugate to the northern hemisphere MEASURE and McMAC chains, offering unique opportunities for inter-hemispheric studies. In particular, we study asymmetries in the power of ULF waves and the role of the ionosphere in such observed asymmetries. Utilizing conjugate magnetometer stations at L=1.7 and L=2.3, we previously demonstrated that the northern hemisphere consistently shows higher ULF wave power. One possible reason for the asymmetry is solar zenith angles differences with the northern hemisphere station being closer to the ecliptic plain and having a higher power ratio. These hemispheric differences were also observed with TEC measurements indicating that the north and south conjugate ionospheres are similarly asymmetric. The initial study was done with Pc3 waves, which include the resonance frequencies for the flux tubes of our conjugate stations. We now extend the study to Pc4 and Pc5 waves that reach the lower latitudes via different mechanisms and compare these waves to the resonant Pc3 waves.

  7. South Central Kansas Gender Equity Project. 1994-95 Annual Report, Field Trip Guide, and Library Resource Catalog.

    ERIC Educational Resources Information Center

    Dodson-Pennington, Laura S.; And Others

    Cowley County Community College established the South Central Kansas Gender Equity Educational Resource Center in 1991-92 to facilitate career awareness, exploration, and preparation by students of all ages, focusing on opportunities in non-traditional fields for both females and males. This document presents an annual report for the Center for…

  8. A COMPREHENSIVE NONPOINT SOURCE FIELD STUDY FOR SEDIMENT, NUTRIENTS AND PATHOGENS IN THE SOUTH FORK BROAD RIVER WATERSHED, GEORGIA

    EPA Science Inventory

    There is an urgent need for EPA to develop protocols for establishing Total Maximum Daily Loads (TMDLs) in streams, lakes and estuaries. A cooperative TMDL field data collection project between ORD and Region 4 is ongoing in the South Fork Broad River Watershed (SFBR), a 245.18 ...

  9. Hydraulic Fracturing of 403 Shallow Diatomite Wells in South Belridge Oil Field, Kern County, California, in 2014

    NASA Astrophysics Data System (ADS)

    Wynne, D. B.; Agusiegbe, V.

    2015-12-01

    We examine all 403 Hydraulic Fracture (HF) jobs performed by Aera Energy, LLC, in the South Belridge oil field, Kern County, CA in 2014. HFs in the South Belridge oil field are atypical amongst North American plays because the reservoir is shallow and produced via vertical wells. Our data set constitutes 88% of all HF jobs performed in CA oil fields in calendar-2014. The South Belridge field produces 11% of California's oil and the shallow HFs performed here differ from most HFs performed elsewhere. We discuss fracture modeling and methods and summary statistics, and modelled dimensions of fractures and their relationships to depth and reservoir properties. The 403 HFs were made in the diatomite-dominated Reef Ridge member of the Monterey Formation. The HFs began at an average depth of 1047 feet below ground (ft TVD) and extended an average of 626 ft vertically downward. The deepest initiation of HF was at 2380 ft and the shallowest cessation was at 639 ft TVD. The average HF was performed using 1488 BBL (62,496 gallons) of water. The HFs were performed in no more than 6 stages and nearly all were completed within one day. We (1) compare metrics of the South Belridge sample group with recent, larger "all-CA" and nationwide samples; and (2) conclude that if relationships of reservoir properties, well completion and HF are well understood, shallow diatomite HF may be optimized to enhance production while minimizing environmental impact.

  10. Determination of the North-South Heliospheric Magnetic-Field Component from Inner-Corona Closed-Loop Propagation

    NASA Astrophysics Data System (ADS)

    Jackson, B. V.; Yu, H. S.; Hick, P. P.; Buffington, A.; Bisi, M. M.; Tokumaru, M.; Kim, J.; Hong, S.; Lee, B.; Yi, J.; Yun, J.

    2015-12-01

    We find that a portion of the north-south interplanetary magnetic field measured in situ near Earth is present from a direct outward mapping of closed fields from the low solar corona. Using the Current-Sheet Source Surface (CSSS) model (Zhao & Hoeksema, 1995 JGR 100, 19), these lower coronal fields are extrapolated upward from near the solar surface. Global velocities inferred from a combination of observations of interplanetary scintillation (IPS) matched to in-situ velocities and densities measured by spacecraft instrumentation provide an accurate outward timing to 1 AU from a model assuming conservation of mass and mass flux. The north-south field component at 1 AU is compared with the appropriate ACE magnetometer in-situ Normal (RTN) or Bn field coordinate (Jackson et al., 2015, ApJL, 803:L1). From a significant positive correlation between this method of determining the Bn field compared with in-situ measurements over a three-year period during the last solar minimum, we find that a small fraction of the low-coronal Bn component flux (~1%) regularly escapes from closed-field regions. Since the Bn field provides the major portion of the Geocentric Solar Magnetospheric (GSM) Bz field component that couples most closely to the Earth's geomagnetic field, the prospects for its determination using this technique for space weather use are being actively developed by our many colleague groups.

  11. 3D airflow dynamics over transverse ridges Mpekweni, South Africa: implications for dune field migration behaviour

    NASA Astrophysics Data System (ADS)

    Jackson, Derek; Cooper, Andrew; Green, Andrew; Beyers, Meiring; Wiles, Errol; Benallack, Keegan

    2016-04-01

    Un-vegetated dune fields provide excellent opportunities to examine airflow dynamics over various types and scales of dune landforms. The three dimensional surface over which lower boundary layers travel, help adjust surface airflow and consequently the aeolian response of the dunes themselves. The use of computational fluid dynamic (CFD) modelling in recent studies now enables investigation of the 3D behaviour of airflow over complex terrain, providing new insights into heterogeneous surface flow and aeolian response of dune surfaces on a large (dunefield) scale. Using a largely un-vegetated coastal dune field site at Mpekweni, Eastern Cape, South Africa, a detailed (0.1m gridded) terrestrial laser scanning survey was conducted to create a high resolution topographical surface. Using local wind flow measurements and local met station records as input, CFD modelling was performed for a number of scenarios involving variable direction and magnitude to examine surface flow patterns across multiple dune forms. Near surface acceleration, expansion and separation of airflow inducing convergence and divergence (steering) of flow velocity streamlines are investigated. Flow acceleration over dune crests/brink lines is a key parameter in driving dune migration and slip face dynamics. Dune aspect ratio (height to length) is also important in determining the degree of crestal flow acceleration, with an increase in flow associated with increasing aspect ratios. Variations in dune height appear to be the most important parameter in driving general flow acceleration. The results from the study provide new insights into dune migration behaviour at this site as well as surface flow behaviour across multiple dune configurations and length scales within un-vegetated dune fields.

  12. Brittle structures in porous sandstones, south central Pyrenees, Spain: field characterization and impact for fluid flow.

    NASA Astrophysics Data System (ADS)

    Saillet, Elodie; Vautier, Yannick; Proudhon, Bennoit; Guilbert, Nathanaël; Hannot, Vincent

    2014-05-01

    In order to better constrain fluids flow circulations in the continental crust, understanding evolution of fault geometry and hydromecanical properties is essential. The knowledge of faulting in analogous reservoirs is particularly important in silicoclastic context. Indeed the high value of natural porosity and the impact of faulting on porosity and permeability will generate potential reservoirs. Depending on the type of faults, deformation in sands and sandstones reservoirs can produces barriers or conduits for fluids. This study focused on an silicoclastic analogous reservoir localised in south central Pyrenees (Spain), named the Aren group, where deformation is recorded by different type of faults. The Aren group is located on the front of the Boixol thrust, on the southern side of the San Corneli anticline. The outcrops are localised in 3 different area, comprised between the towns of Aren, Tremp and Isona. Depending of the outcrop, we identify presence of veins, joints, deformation bands (DBs) and some few sites where both of them are recorded in the same unit. We present a complete field study, based on two different field mapping methods : (i) field photomosaiques and associated detail 2D mapping ; (ii) linear scanlines along deformed outcrops. These two different methods, applied around ten outcrops allow us to obtain : (1) 30 meters squares of 2D detailed maps of fractures and linkage information ; (2) 90 linear meters of fracture density vs. distance all along the outcrop for each type of fracture. Field measurements and quantification was completed by a systematic sampling, in order to give an access to (i) microtectonic elements and fine characterisation of the different fault types by SEM observations ; (ii) a porosity quantification of host rock and fault zones based on the SEM pictures. Field data shows a strong relationship between the different types of brittle structures. On the Aren outcrop, fine DBs (wich act as barriers) are located in

  13. Ground-based instrumentation for measurements of atmospheric conduction current and electric field at the South Pole

    NASA Technical Reports Server (NTRS)

    Byrne, G. J.; Benbrook, J. R.; Bering, E. A.; Few, A. A.; Morris, G. A.; Trabucco, W. J.; Paschal, E. W.

    1993-01-01

    Attention is given to instruments constructed to measure the atmospheric conduction current and the atmospheric electric field - two fundamental parameters of the global-electric circuit. The instruments were deployed at the Amundsen-Scott South Pole Station in January 1991 and are designed to operate continuously for up to one year without operator intervention. The atmospheric current flows into one hemisphere, through the electronics where it is measured, and out the other hemisphere. The electric field is measured by a field mill of the rotating dipole type. Sample data from the first days of operation at the South Pole indicate variations in the global circuit over time scales from minutes to hours to days.

  14. X-ray observations of dust obscured galaxies in the Chandra deep field south

    NASA Astrophysics Data System (ADS)

    Corral, A.; Georgantopoulos, I.; Comastri, A.; Ranalli, P.; Akylas, A.; Salvato, M.; Lanzuisi, G.; Vignali, C.; Koutoulidis, L.

    2016-08-01

    We present the properties of X-ray detected dust obscured galaxies (DOGs) in the Chandra deep field south. In recent years, it has been proposed that a significant percentage of the elusive Compton-thick (CT) active galactic nuclei (AGN) could be hidden among DOGs. This type of galaxy is characterized by a very high infrared (IR) to optical flux ratio (f24 μm/fR > 1000), which in the case of CT AGN could be due to the suppression of AGN emission by absorption and its subsequent re-emission in the IR. The most reliable way of confirming the CT nature of an AGN is by X-ray spectroscopy. In a previous work, we presented the properties of X-ray detected DOGs by making use of the deepest X-ray observations available at that time, the 2Ms observations of the Chandra deep fields, the Chandra deep field north (CDF-N), and the Chandra deep field south (CDF-S). In that work, we only found a moderate percentage (<50%) of CT AGN among the DOGs sample. However, we pointed out that the limited photon statistics for most of the sources in the sample did not allow us to strongly constrain this number. In this paper, we further explore the properties of the sample of DOGs in the CDF-S presented in that work by using not only a deeper 6Ms Chandra survey of the CDF-S, but also by combining these data with the 3Ms XMM-Newton survey of the CDF-S. We also take advantage of the great coverage of the CDF-S region from the UV to the far-IR to fit the spectral energy distributions (SEDs) of our sources. Out of the 14 AGN composing our sample, 9 are highly absorbed (NH > 1023 cm-2), whereas 2 look unabsorbed, and the other 3 are only moderately absorbed. Among the highly absorbed AGN, we find that only three could be considered CT AGN. In only one of these three cases, we detect a strong Fe Kα emission line; the source is already classified as a CT AGN with Chandra data in a previous work. Here we confirm its CT nature by combining Chandra and XMM-Newton data. For the other two CT

  15. Selected First Results from the 7 Ms Chandra Deep Field-South Survey

    NASA Astrophysics Data System (ADS)

    Brandt, W. Niel; Chandra Deep Field-South Team

    2017-01-01

    The exposure on the Chandra Deep Field-South (CDF-S) has recently been increased to 7 Ms, making it the most sensitive extragalactic X-ray survey by a wide margin. About 1050 X-ray sources have been detected, primarily distant active galactic nuclei (AGNs) and starburst/normal galaxies. The unmatched deep multiwavelength coverage for these sources allows superb follow-up investigations; e.g., 98.4% of the X-ray sources have multiwavelength counterparts, and 97.8% have spectroscopic/photometric redshifts. I will briefly describe the source catalog for the 7 Ms CDF-S and some exciting first science results. The latter will likely include (1) constraints on SMBH growth in the first galaxies as revealed by direct detection and stacking; (2) long-term variability studies of the AGNs producing most of cosmic accretion power; (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs; and (4) measurements of the evolving X-ray binary populations of normal and starburst galaxies.

  16. Findings of the SHIVA field campaign in the South China Sea in Nov.-Dec. 2011

    NASA Astrophysics Data System (ADS)

    Pfeilsticker, Klaus

    2013-04-01

    Marine emissions of so-called halogenated very short-lived substances (VSLS) are known to considerably contribute to the ozone destroying halogen loading of the stratosphere. In this context, most crucial are VSLS emissions in regions of large vertical transport, i.e. the tropics and in particular in the warm pool of the Western Pacific during the rainy seasons (November to March). In order to study the biogenic emissions of halogenated VSLS, their atmospheric transport and transformation, the internationally coordinated field expedition SHIVA (Stratospheric ozone: Halogen Impacts in a Varying Atmosphere) was performed within the margins of the South China Sea in November and December 2011. Partners from 19 institutions from 9 countries participated in the campaign. Funding came from the EU's 7th framework programme and additionally from a larger number of national funding agencies. The activities included investigations in the laboratory and on the ground, during local ship cruises, the research vessel SONNE, deployments of the DLR (Germany's national research center for aeronautics and space) Falcon aircraft around Borneo, simultaneous satellite observations, the meteorological forecasting and analysis, and numerical modeling of atmospheric transport and photochemistry. The present talk provides an overview on the performed research activities, reports on joint studies, and some core research results obtained to date.

  17. Findings of the SHIVA field campaign in the South China Sea in Nov.-Dec. 2011

    NASA Astrophysics Data System (ADS)

    Pfeilsticker, K.

    2012-12-01

    Marine emissions of so-called halogenated very short-lived substances (VSLS) are known to considerably contribute to the ozone destroying halogen loading of the stratosphere. In this context, most crucial are VSLS emissions in regions of large vertical transport, i.e. the tropics and in particular in the warm pool of the Western Pacific during the rainy seasons (November to March). In order to study the biogenic emissions of halogenated VSLS, their atmospheric transport and transformation, the internationally coordinated field expedition SHIVA (Stratospheric ozone: Halogen Impacts in a Varying Atmosphere) was performed within the margins of the South China Sea in November and December 2011. Partners from 19 institutions from 9 countries participated in the campaign and funding came from the EU's 7th framework programme and additionally from a larger number of national funding agencies. The activities included investigations in the laboratory and on the ground, during local ship cruises, the research vessel SONNE, deployments of the DLR (Germany's national research center for aeronautics and space) Falcon aircraft around Borneo, simultaneous satellite observations, the meteorological forecasting and analysis, and numerical modelling of atmospheric transport and photochemistry. The present talk provides an overview on the performed research activities, and reports on joint studies and the research results obtained to date.

  18. RADIO AND MID-INFRARED IDENTIFICATION OF BLAST SOURCE COUNTERPARTS IN THE CHANDRA DEEP FIELD SOUTH

    SciTech Connect

    Dye, Simon; Ade, Peter A. R.; Eales, Stephen A.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Moncelsi, Lorenzo; Pascale, Enzo; Bock, James J.; Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Devlin, Mark J.; Klein, Jeff; Dunlop, James S.; Gundersen, Joshua O.; Hughes, David H.; Magnelli, Benjamin; Olmi, Luca

    2009-09-20

    We have identified radio and/or mid-infrared counterparts to 198 out of 350 sources detected at >=5{sigma} over {approx}9 deg{sup 2} centered on the Chandra Deep Field South by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) at 250, 350, and 500 {mu}m. We have matched 114 of these counterparts to optical sources with previously derived photometric redshifts and fitted spectral energy distributions to the BLAST fluxes and fluxes at 70 and 160 {mu}m acquired with the Spitzer Space Telescope. In this way, we have constrained dust temperatures, total far-infrared/submillimeter luminosities, and star formation rates for each source. Our findings show that, on average, the BLAST sources lie at significantly lower redshifts and have significantly lower rest-frame dust temperatures compared to submillimeter sources detected in surveys conducted at 850 {mu}m. We demonstrate that an apparent increase in dust temperature with redshift in our sample arises as a result of selection effects. Finally, we provide the full multiwavelength catalog of >=5{sigma} BLAST sources contained within the complete {approx}9 deg{sup 2} survey area.

  19. Identification of Active Galactic Nuclei through HST optical variability in the GOODS South field

    NASA Astrophysics Data System (ADS)

    Pouliasis, Ektoras; Georgantopoulos; Bonanos, A.; HCV Team

    2016-08-01

    This work aims to identify AGN in the GOODS South deep field through optical variability. This method can easily identify low-luminosity AGN. In particular, we use images in the z-band obtained from the Hubble Space Telescope with the ACS/WFC camera over 5 epochs separated by ~45 days. Aperture photometry has been performed using SExtractor to extract the lightcurves. Several variability indices, such as the median absolute deviation, excess variance, and sigma were applied to automatically identify the variable sources. After removing artifacts, stars and supernovae from the variable selected sample and keeping only those sources with known photometric or spectroscopic redshift, the optical variability was compared to variability in other wavelengths (X-rays, mid-IR, radio). This multi-wavelength study provides important constraints on the structure and the properties of the AGN and their relation to their hosts. This work is a part of the validation of the Hubble Catalog of Variables (HCV) project, which has been launched at the National Observatory of Athens by ESA, and aims to identify all sources (pointlike and extended) showing variability, based on the Hubble Source Catalog (HSC, Whitmore et al. 2015). The HSC version 1 was released in February 2015 and includes 80 million sources imaged with the WFPC2, ACS/WFC, WFC3/UVIS and WFC3/IR cameras.

  20. The internal seiche field in the changing South Aral Sea (2006-2013)

    NASA Astrophysics Data System (ADS)

    Roget, Elena; Khimchenko, Elizaveta; Forcat, Francesc; Zavialov, Peter

    2017-02-01

    Internal standing waves (seiches) in the South Aral Sea are studied for the first time. The study, based on numerical simulations and field data, focuses on two different campaigns: the first in autumn 2006, when the stratification was weak and there was a mild prevailing northeasterly wind, and the second in autumn 2013, when the stratification was strong and there was a mild easterly wind. Between these two campaigns, the sea surface level decreased by 3.2 m. The periods of the fundamental modes were identified as 36 and 14 h, respectively. In both years, either second or third vertical modes were found. In general, the vertical modes in 2013 were higher because of the broad and strong pycnocline. For both years, it was found that the deep quasi-homogeneous mixed upper layer could sustain internal waves under mild wind conditions. The observed first and second vertical modes in 2006 are the first and second horizontal modes and the second and third vertical modes in 2013 are the second and third horizontal modes. The results suggest that, due to sea level variations, the neck connecting the Chernyshev Bay to the main body of the lake can become a critical location for the development of a nodal line for all principal oscillation modes. Rotation effects on waves were not analyzed in this study.

  1. Impacts of spinosad and λ-cyhalothrin on spider communities in cabbage fields in south Texas.

    PubMed

    Liu, T-X; Irungu, R W; Dean, D A; Harris, M K

    2013-04-01

    Spiders are a principal arthropod group that preys on numerous pests of vegetables and other crops. In this study, we determined the effects of the two most commonly used insecticides, spinosad and λ-cyhalothrin, on diversity of spiders on cabbage in south Texas. In two seasons (fall 2008 and spring 2009), we collected a total of 588 spiders belonging to 53 species in 11 families from spinosad and λ-cyhalothrin-treated cabbages and the untreated control plants. A great majority of spiders were collected from the pitfall traps (554) where only a few (34) were collected from the blower/vacuum sampling. In the insecticide-treated plots, there were significantly fewer spider individuals, species and families than in untreated fields. Spinosad had significantly less effect on spiders in total individuals, number of species and families than λ-cyhalothrin. The effects of the two insecticides were further demonstrated by the Shannon-Weiner index (H') and the hierarchical richness index (HRI). Spider diversity in the spinosad-treated plots were not significantly different from that in the untreated fields but were greater than those in λ-cyhalothrin-treated plots in both seasons when measured by H' values. In contrast, the H' values of spider's diversity in the λ-cyhalothrin-treated plots were significantly lower than spinosad-treated and untreated plots. High values of HRI for spider richness in the spinosad-treated plots suggested that spinosad had less effect on spiders than λ-cyhalothrin. We concluded that spinosad was more compatible with spiders on cabbage compared to λ-cyhalothrin and that this information should be used when developing insecticide resistance management strategies.

  2. Impacts of Humic Injection Experiments on the South Oyster Field Research Site

    SciTech Connect

    John F. McCarthy

    2004-04-27

    A closure plan for the South Oyster Focus Area (SOFA) is being implemented to assess the impacts of a series of experimental injections of microorganisms, tracers and chemical amendments on the chemical and physical properties of the aquifer. The proposed research addresses environmental monitoring of humic substances injected into the aquifer, as described in the Site Closure Plan for the South Oyster Field Research Site. The goal of the research is to demonstrate that the dissolved organic matter (DOM) in the groundwater at and downgradient from the injection site has returned to a pre-injection �baseline� conditions with respect to either the concentration or chemical composition of the DOM. For clarity, the humic solution injected during the experiment will be referred to as �humic injectate.� The term �DOM� will refer to the organic material recovered in the groundwater, which includes the autochthonous groundwater DOM as well as any of the humic injectate remaining in the groundwater. Specific objectives include: � Estimate the amount of humic material remaining in the aquifer at the completion of the push-pull experiment and the potential for environmental impacts due to release of humics retained on the sediments. � Monitor the DOM concentrations in groundwater over time at the injection well and at sampling locations within the potential downgradient plume of the injected tracers. � Evaluate the chemical composition of the DOM to determine whether the injection experiment had an impact of the chemical properties of the aquifer. The product of this research will be a contribution to the Site Closure Report documenting the impact of the humic experiments on the aquifer. Return of the aquifer to a �baseline� conditions will be achieved if the DOM concentrations in the groundwater are determined over the course of the research to have decreased to the pre-injection level, or if the chemical properties of

  3. Clusters, groups, and filaments in the Chandra deep field-south up to redshift 1

    SciTech Connect

    Dehghan, S.; Johnston-Hollitt, M.

    2014-03-01

    We present a comprehensive structure detection analysis of the 0.3 deg{sup 2} area of the MUSYC-ACES field, which covers the Chandra Deep Field-South (CDFS). Using a density-based clustering algorithm on the MUSYC and ACES photometric and spectroscopic catalogs, we find 62 overdense regions up to redshifts of 1, including clusters, groups, and filaments. We also present the detection of a relatively small void of ∼10 Mpc{sup 2} at z ∼ 0.53. All structures are confirmed using the DBSCAN method, including the detection of nine structures previously reported in the literature. We present a catalog of all structures present, including their central position, mean redshift, velocity dispersions, and classification based on their morphological and spectroscopic distributions. In particular, we find 13 galaxy clusters and 6 large groups/small clusters. Comparison of these massive structures with published XMM-Newton imaging (where available) shows that 80% of these structures are associated with diffuse, soft-band (0.4-1 keV) X-ray emission, including 90% of all objects classified as clusters. The presence of soft-band X-ray emission in these massive structures (M {sub 200} ≥ 4.9 × 10{sup 13} M {sub ☉}) provides a strong independent confirmation of our methodology and classification scheme. In the closest two clusters identified (z < 0.13) high-quality optical imaging from the Deep2c field of the Garching-Bonn Deep Survey reveals the cD galaxies and demonstrates that they sit at the center of the detected X-ray emission. Nearly 60% of the clusters, groups, and filaments are detected in the known enhanced density regions of the CDFS at z ≅ 0.13, 0.52, 0.68, and 0.73. Additionally, all of the clusters, bar the most distant, are found in these overdense redshift regions. Many of the clusters and groups exhibit signs of ongoing formation seen in their velocity distributions, position within the detected cosmic web, and in one case through the presence of tidally

  4. Schmallenberg virus infection in South American camelids: Field and experimental investigations.

    PubMed

    Schulz, Claudia; Beer, Martin; Hoffmann, Bernd

    2015-11-18

    During the first epizootic wave of the novel, teratogenic Schmallenberg virus (SBV, Orthobunyavirus) in ruminants in Northern Europe, serological evidence of a previous SBV-infection demonstrated that South American camelids (SAC) are also susceptible to SBV. However, their potential role in SBV spread remains unknown. To investigate the prevalence and course of SBV-infection in SAC, a German field study and an animal trial with three llamas and three alpacas were conducted. From September 2012 to December 2013, 313 of 502 SAC (62.35%) were found SBV seropositive, but negative for SBV-RNA. The estimated between-district (94.23% of 52) and median within-district (71.43%) and herd (73.13%) SBV seroprevalence in German SAC was similar to the seroprevalence reported in cattle herds and sheep flocks at the time. An age of >1 year was found a statistically significant risk factor for SBV-infection, which could be explained by the spatio-temporal spread of SBV in Germany during the study period. No clinical signs or an increase of abortion and congenital malformation associated with SBV-infection in SAC were reported by the study participants. Similar to SBV-infected ruminants, SBV-RNAemia in experimentally SBV-infected SAC was detected for a short time between days 3 and 7 after infection (dpi), and seroconversion occurred between 9 and 21 dpi. Despite the similar virological and serological results, the lack of clinical signs and congenital malformation associated with SBV-infection suggests that SBV causes subclinical infection in SAC. However, their role as reservoirs in the spread of SBV has to be further investigated.

  5. The Chandra Deep Field-South Survey: 7 Ms Source Catalogs

    NASA Astrophysics Data System (ADS)

    Luo, B.; Brandt, W. N.; Xue, Y. Q.; Lehmer, B.; Alexander, D. M.; Bauer, F. E.; Vito, F.; Yang, G.; Basu-Zych, A. R.; Comastri, A.; Gilli, R.; Gu, Q.-S.; Hornschemeier, A. E.; Koekemoer, A.; Liu, T.; Mainieri, V.; Paolillo, M.; Ranalli, P.; Rosati, P.; Schneider, D. P.; Shemmer, O.; Smail, I.; Sun, M.; Tozzi, P.; Vignali, C.; Wang, J.-X.

    2017-01-01

    We present X-ray source catalogs for the ≈7 Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 arcmin2. Utilizing wavdetect for initial source detection and ACIS Extract for photometric extraction and significance assessment, we create a main source catalog containing 1008 sources that are detected in up to three X-ray bands: 0.5–7.0 keV, 0.5–2.0 keV, and 2–7 keV. A supplementary source catalog is also provided, including 47 lower-significance sources that have bright ({K}s≤slant 23) near-infrared counterparts. We identify multiwavelength counterparts for 992 (98.4%) of the main-catalog sources, and we collect redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts. Based on the X-ray and multiwavelength properties, we identify 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous ≈4 Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. We have achieved unprecedented X-ray sensitivity with average flux limits over the central ≈1 arcmin2 region of ≈1.9 × 10‑17, 6.4 × 10‑18, and 2.7 × 10‑17 erg cm‑2 s‑1 in the three X-ray bands, respectively. We provide cumulative number-count measurements observing, for the first time, that normal galaxies start to dominate the X-ray source population at the faintest 0.5–2.0 keV flux levels. The highest X-ray source density reaches ≈50,500 deg‑2, and 47% ± 4% of these sources are AGNs (≈23,900 deg‑2).

  6. Near-Field Deformation Associated with the M6.0 South Napa Earthquake Surface Rupture

    NASA Astrophysics Data System (ADS)

    Brooks, B. A.; Hudnut, K. W.; Glennie, C. L.; Ericksen, T.

    2014-12-01

    We characterize near-field deformation associated with the surface rupture of the M6.0 South Napa earthquake from repeat mobile laser scanning (MLS) surveys. Starting the day after the main shock, we operated, sometime simultaneously, short (~75 m range) and medium (~400m range) range laser scanners on a truck or backpack. We scanned most of the length of the principal and secondary surface ruptures at speeds less than 10 km/hr. Scanning occurred primarily in either suburban subdivisions or cultivated vineyards of varying varietals with differing leaf patterns and stages of maturity. Spot-spacing is dense enough (100s of points/m^2) to permit creation of 10-25cm digital elevation models of much of the surface rupture. Scanned features of the right-lateral rupture include classic mole tracks through a variety of soil types, en echelon cracks, offset vine rows, and myriad types of pavement-related deformation. We estimate coseismic surface displacements ranging from 5 to 45 cm by examining offset cultural features and vine rows and by comparing the MLS data with preexisting airborne laser scans from 2003 using point-cloud and solid-modeling methodologies. Additionally, we conducted repeat MLS scans to measure the magnitude and spatial variation of fault afterslip, exceeding 20 cm in some places, particularly in the southern portion of the rupture zone. We anticipate these data sets, in conjunction with independently collected ground-based alinement arrays and space-based geodetic data will contribute significant insight into topics of current debate including assessing the most appropriate material models for shallow fault zones and how shallow and deeper fault slip relate to one another.

  7. Preface to the special issue on "Regional moment tensors and stress field in South and Central America"

    NASA Astrophysics Data System (ADS)

    Audemard, Franck; Zahradnik, Jiri; Assumpção, Marcelo

    2016-11-01

    This special issue follows from the Symposium "Regional Moment Tensor Solutions: advances and new applications" held in Bogotá, Colombia, at the I Regional Assembly of the IASPEI's Latin American and Caribbean Seismological Commission (LACSC) in 2014. Seven papers are presented dealing with determination of moment tensors, focal mechanisms and the stress field in Central and South America. The study areas of each paper are indicated in the index Map of Fig. 1.

  8. Public health systems strengthening in Africa: the role of South Africa Field Epidemiology and Laboratory Training Programme.

    PubMed

    Kuonza, Lazarus; Tint, Khin San; Harris, Bernice; Nabukenya, Immaculate

    2011-01-01

    The South Africa Field Epidemiology and Laboratory Training Programme (SAFELTP) was created in 2006 after recognizing the need to build and sustain the country's human resource capacity in field (applied) epidemiology and public health practice. The programme was formed as a collaboration between the South Africa Department of Health (DoH), the National Institute for Communicable Diseases (NICD), the National Health Laboratory Services (NHLS), the US Centers for Disease Control and Prevention (CDC) and the University of Pretoria. The primary goal of the programme was to produce field-trained epidemiologists equipped with knowledge and practical skills to effectively and efficiently address the public health priorities of South Africa. SAFELTP is a 2-year full-time training, consisting of a combination of classroom-based instruction (30%) and mentored field work (70%). The training places emphasis on public health surveillance, investigation of disease epidemics, public health laboratory practice and communication of epidemiologic information, among other aspects of epidemiology research. At completion, residents are awarded a Master of Public Health (MPH) degree from the University of Pretoria. Since its inception in 2006, 48 residents have enrolled onto the programme and 30 (62%) of them have completed the training. Over the past 5 years, the residents have conducted more than 92 outbreak investigations, 47 surveillance evaluations, 19 planned studies, analyzed 37 large databases and presented more than 56 papers at local and international conferences. In recognition of the high-quality work, at least five SAFELTP residents have received awards at various international scientific conferences during the 5 years. In conclusion, the South Africa FELTP is now fully established and making valuable contributions to the country's public health system, albeit with innumerable challenges.

  9. A WFC3 Grism Emission Line Redshift Catalog in the GOODS-South Field

    NASA Astrophysics Data System (ADS)

    Morris, Aaron M.; Kocevski, Dale D.; Trump, Jonathan R.; Weiner, Benjamin J.; Hathi, Nimish P.; Barro, Guillermo; Dahlen, Tomas; Faber, Sandra M.; Finkelstein, Steven L.; Fontana, Adriano; Ferguson, Henry C.; Grogin, Norman A.; Grützbauch, Ruth; Guo, Yicheng; Hsu, Li-Ting; Koekemoer, Anton M.; Koo, David C.; Mobasher, Bahram; Pforr, Janine; Salvato, Mara; Wiklind, Tommy; Wuyts, Stijn

    2015-06-01

    We combine Hubble Space Telescope (HST)/Wide Field Camera3 (WFC3) imaging and G141 grism observations from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and 3D-HST surveys to produce a catalog of grism spectroscopic redshifts for galaxies in the CANDELS/GOODS-South field. The WFC3/G141 grism spectra cover a wavelength range of 1.1≤slant λ ≤slant 1.7 μm with a resolving power of R∼ 130 for point sources, thus providing rest-frame optical spectra for galaxies out to z∼ 3.5. The catalog is selected in the H-band (F160W) and includes both galaxies with and without previously published spectroscopic redshifts. Grism spectra are extracted for all H-band detected galaxies with H ≤slant 24 and a CANDELS photometric redshift {{z}phot}≥slant 0.6. The resulting spectra are visually inspected to identify emission lines, and redshifts are determined using cross-correlation with empirical spectral templates. To establish the accuracy of our redshifts, we compare our results against high-quality spectroscopic redshifts from the literature. Using a sample of 411 control galaxies, this analysis yields a precision of {{σ }NMAD}=0.0028 for the grism-derived redshifts, which is consistent with the accuracy reported by the 3D-HST team. Our final catalog covers an area of 153 arcmin2 and contains 1019 redshifts for galaxies in GOODS-S. Roughly 60% (608/1019) of these redshifts are for galaxies with no previously published spectroscopic redshift. These new redshifts span a range of 0.677≤slant z≤slant 3.456 and have a median redshift of z = 1.282. The catalog contains a total of 234 new redshifts for galaxies at z\\gt 1.5. In addition, we present 20 galaxy pair candidates identified for the first time using the grism redshifts in our catalog, including four new galaxy pairs at z∼ 2, nearly doubling the number of such pairs previously identified.

  10. [Effects of different fertilization modes on paddy field topsoil organic carbon content and carbon sequestration duration in South China].

    PubMed

    Zhu, Li-Qun; Yang, Min-Fang; Xu, Min-Lun; Zhang, Wu-Yi; Bian, Xin-Min

    2012-01-01

    Based on the organic carbon data of 222 topsoil samples taken from 38 paddy field experiment sites in South China, calculations were made on the relative annual change of topsoil organic carbon content (RAC) and carbon sequestration duration in the paddy fields in South China under five fertilization modes (inorganic nitrogen fertilization, N; inorganic nitrogen and phosphorus fertilization, NP; inorganic nitrogen, phosphorus, and potassium fertilization, NPK; organic fertilization, O; and inorganic plus organic fertilization, OF). The RAC under the fertilizations was 0-0.4 g x kg(-1) x a(-1), with an increment of 0.20 and 0.26 g x kg(-1) x a(-1) in double and triple cropping systems, respectively. The RAC was higher in treatments O and OF than in treatments N, NP, and NPK, being the highest (0.32 g x kg(-1) x a(-1)) in treatment OF. The topsoil organic carbon accumulation rate decreased with increasing time, and the carbon sequestration duration in treatments N, NP, NPK, O, and OF was about 22, 28, 38, 57, and 54 years, respectively. Inorganic plus organic fertilization was the most effective practice for soil carbon sequestration in the paddy fields in South China.

  11. A test field for Gaia. Radial velocity catalogue of stars in the South Ecliptic Pole

    NASA Astrophysics Data System (ADS)

    Frémat, Y.; Altmann, M.; Pancino, E.; Soubiran, C.; Jofré, P.; Damerdji, Y.; Heiter, U.; Royer, F.; Seabroke, G.; Sordo, R.; Blanco-Cuaresma, S.; Jasniewicz, G.; Martayan, C.; Thévenin, F.; Vallenari, A.; Blomme, R.; David, M.; Gosset, E.; Katz, D.; Viala, Y.; Boudreault, S.; Cantat-Gaudin, T.; Lobel, A.; Meisenheimer, K.; Nordlander, T.; Raskin, G.; Royer, P.; Zorec, J.

    2017-01-01

    Context. Gaia is a space mission that is currently measuring the five astrometric parameters, as well as spectrophotometry of at least 1 billion stars to G = 20.7 mag with unprecedented precision. The sixth parameter in phase space (i.e., radial velocity) is also measured thanks to medium-resolution spectroscopy that is being obtained for the 150 million brightest stars. During the commissioning phase, two fields, one around each ecliptic pole, have been repeatedly observed to assess and to improve the overall satellite performances, as well as the associated reduction and analysis software. A ground-based photometric and spectroscopic survey was therefore initiated in 2007, and is still running to gather as much information as possible about the stars in these fields. This work is of particular interest to the validation of the radial velocity spectrometer outputs. Aims: The paper presents the radial velocity measurements performed for the Southern targets in the 12-17 R magnitude range on high- to mid-resolution spectra obtained with the GIRAFFE and UVES spectrographs. Methods: Comparison of the South Ecliptic Pole (SEP) GIRAFFE data to spectroscopic templates observed with the HERMES (Mercator in La Palma, Spain) spectrograph enabled a first coarse characterisation of the 747 SEP targets. Radial velocities were then obtained by comparing the results of three different methods. Results: In this paper, we present an initial overview of the targets to be found in the 1 sq. deg SEP region that was observed repeatedly by Gaia ever since its commissioning. In our representative sample, we identified one galaxy, six LMC S-stars, nine candidate chromospherically active stars, and confirmed the status of 18 LMC Carbon stars. A careful study of the 3471 epoch radial velocity measurements led us to identify 145 RV constant stars with radial velocities varying by less than 1 km s-1. Seventy-eight stars show significant RV scatter, while nine stars show a composite spectrum

  12. The sub-mJy radio population in the Extended Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Bonzini, M.

    2014-06-01

    Deep radio observations provide a dust unbiased view of both black hole (BH) and star formation (SF) activity and therefore represent a powerful tool to investigate their evolution and their possible mutual influence across cosmic time. Radio astronomy is therefore becoming increasingly important for galaxy evolution studies thanks also to the many new radio facilities under construction or being planned. To maximise the potentiality of these new instruments it is crucial to make predictions on what they will observe and to see how best to complement the radio data with multi-wavelength information. These are the motivations of my Thesis in which I studied a sample of 900 sources detected in one of the deepest radio surveys ever made. The observations have been performed at 1.4 GHz with the Very Large Array on the Extended Chandra Deep Field South. I developed a multi-wavelength method to identify the optical-infrared counterparts of the radio sources and to classify them as radio-loud active galactic nuclei (RL AGNs), radio-quiet (RQ) AGNs, and star forming galaxies (SFGs). I was able for the first time to quantify the relative contribution of these different classes of sources down to a radio flux density limit of ∼30 μJy. I characterized the host galaxy properties (stellar masses, optical colors, and morphology) of the radio sources; RQ AGN hosts and SFGs have similar properties with disk morphology and blue colors while radio-loud AGN hosts are more massive, redder and mostly ellipticals. This suggests that the RQ and RL activity occurs at two different evolutionary stages of the BH-host galaxy co-evolution. The RQ phase occurs at earlier times when the galaxy is still gas rich and actively forming stars while the radio activity of the BH appears when the galaxy has already formed the bulk of its stellar population, the gas supply is lower, and the SF is considerably reduced. I quantified the star formation rate (SFR) of the radio sources using two

  13. A COMPREHENSIVE NONPOINT SOURCE FIELD STUDY FOR SEDIMENT, NUTRIENTS, AND PATHOGENS IN THE SOUTH FORK BROAD RIVER WATERSHED IN NORTHEAST GEORGIA

    EPA Science Inventory

    This technical report provides a description of the field project design, quality control, the sampling protocols and analysis methodology used, and standard operating procedures for the South Fork Broad River Watershed (SFBR) Total Maximum Daily Load (TMDL) project. This watersh...

  14. Regional stratigraphy of Smackover limestone (Jurassic) in south Arkansas and north Louisiana, and geology of Chalybeat Springs oil field

    SciTech Connect

    Troell, A.R.; Robinson, J.D.

    1987-09-01

    Prior to 1960, the Reynolds oolite of the Smackover Formation of south Arkansas, was correlated with the Smackover B oolite of north Louisiana. The absence of anticlines with structural closure and the paucity of untested fault closures along the Arkansas-Louisiana boundary provided little exploratory interest in the area. Discovery of oil at Lick Creek field in 1960 and at Walker Creek in 1968 revealed a trend of traps and led to the geologic investigation that resulted in the discovery, in 1972, of Chalybeat Springs field, in Columbia County, Arkansas. Chalybeat Springs field is a combination stratigraphic-structural trap in oolitic calcarenite at a depth of 10,250 ft in the Smackover B limestone. Production is limited by the combination of a tilted anticline with porosity pinch-out on its flank. The field originally had 28 producing wells and 10 dry holes, and covered approximately 4500 productive acres. Original oil in place is estimated to have been 37 million bbl and cumulative production through 1985 was approximately 12 million bbl. The geologic relationships and principles observed in the Smackover Limestone of south Arkansas and north Louisiana have been successfully applied to other regions and in carbonate strata of different age, in the search for oil and gas production. Practical geologic studies of carbonate rocks, aided by examination of drill cuttings, cores, and thin sections, combined with mechanical log evaluation, result in lower finding costs for oil and gas reserves.

  15. Reconnaissance of Field Sites for the Study of Chemical Weathering on the Guayana Shield, South America

    SciTech Connect

    Steefell, C I

    2003-02-01

    Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic process level, the important controls on chemical weathering (physical erosion, temperature, precipitation) can be folded into larger scale models tracking the global carbon cycle. Our goal in this study was to carry out the preliminary work needed to establish a field research site for chemical weathering om the Cuayana Shield in South America. The Guayana Shield is a Precambrian province greater than 1.5 billion years old covering portions of Venezuela, Guyana (the country), Surinam, French Guiana, and Brazil (Figure 1). More important than the age of the rocks themselves, however, is the age of the erosion surface developed on the Shield, with

  16. Tracking Holland Interest Codes: The Case of South African Field Guides

    ERIC Educational Resources Information Center

    Watson, Mark B.; Foxcroft, Cheryl D.; Allen, Lynda J.

    2007-01-01

    Holland believes that specific personality types seek out matching occupational environments and his theory codes personality and environment according to a six letter interest typology. Since 1985 there have been numerous American studies that have queried the validity of Holland's coding system. Research in South Africa is scarcer, despite…

  17. South Dakota Air National Guard Joe Foss Field, Sioux Falls, SD. Remedial Investigation

    DTIC Science & Technology

    1990-09-01

    immediately opposite the Diversion Channel from the airport is devoted to the State prison farm. Schools located within 1 mile of the Base include Jane ... Addams elementary school (250 students), and Axtell Park Junior High School (675 students) which are both south of the Base. 3.9.2 Population and Age

  18. Field evaluation of potential pheromone lures for Lygus lineolaris (Hemiptera: Miridae) in the Mid-South

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant bugs (Hemiptera: Miridae) are phytophagous pests of cultivated plants around the world. In the mid-South region of the United States, Lygus lineolaris is a primary pest of cotton, and causes economic damage. Previously published research about the volatiles produced by members of the genus Lyg...

  19. Orthogonal fracture formation in the South Wales coalfield: implications from a field study and fluid overpressure of quartz veins

    NASA Astrophysics Data System (ADS)

    Fukunari, Tetsuzo; Gudmundsson, Agust

    2014-05-01

    and 18 MPa for those striking east-west. Although the thick Dinantian Carbonates immediately underlie the sandstones of the Coal Measure Group, carbonate minerals are absent in the veins, suggesting that the main driving stress for fracture formation may not have been buoyancy related to a deeper fluid source in the underlying carbonates but rather local stress concentrations, resulting in differential stresses, in the sandstones. These conditions imply that both north-south and east-west extensional stress fields were induced in the sandstones during the basin growth under the regional north-south compression. The process responsible for the north-south extension within the sandstones is, at this stage, not entirely clear. One possibility is that cyclic stress and strain concentration in thrust zones could induce tensile stresses during stress relaxation of syn- and post-slip period of major thrusts. Viscous behaviour of the shale in the study area may have generated the north-south tensile stress fields in the sandstones that resulted in fracture formation.

  20. Time lapse seismic observations and effects of reservoir compressibility at Teal South oil field

    NASA Astrophysics Data System (ADS)

    Islam, Nayyer

    One of the original ocean-bottom time-lapse seismic studies was performed at the Teal South oil field in the Gulf of Mexico during the late 1990's. This work reexamines some aspects of previous work using modern analysis techniques to provide improved quantitative interpretations. Using three-dimensional volume visualization of legacy data and the two phases of post-production time-lapse data, I provide additional insight into the fluid migration pathways and the pressure communication between different reservoirs, separated by faults. This work supports a conclusion from previous studies that production from one reservoir caused regional pressure decline that in turn resulted in liberation of gas from multiple surrounding unproduced reservoirs. I also provide an explanation for unusual time-lapse changes in amplitude-versus-offset (AVO) data related to the compaction of the producing reservoir which, in turn, changed an isotropic medium to an anisotropic medium. In the first part of this work, I examine regional changes in seismic response due to the production of oil and gas from one reservoir. The previous studies primarily used two post-production ocean-bottom surveys (Phase I and Phase II), and not the legacy streamer data, due to the unavailability of legacy prestack data and very different acquisition parameters. In order to incorporate the legacy data in the present study, all three post-stack data sets were cross-equalized and examined using instantaneous amplitude and energy volumes. This approach appears quite effective and helps to suppress changes unrelated to production while emphasizing those large-amplitude changes that are related to production in this noisy (by current standards) suite of data. I examine the multiple data sets first by using the instantaneous amplitude and energy attributes, and then also examine specific apparent time-lapse changes through direct comparisons of seismic traces. In so doing, I identify time-delays that, when

  1. Oil recovery in a low-permeability, wave-dominated, Cretaceous, deltaic reservoir, Big Wells (San Miguel) field, south Texas

    SciTech Connect

    Tyler, N.; Gholston, J.C.; Ambrose, W.A.

    1987-10-01

    The Upper Cretaceous Big Wells (San Miguel) reservoir in Dimmit and Zavala Counties, south Texas, produces from a broadly lenticular, wave-dominated deltaic sandstone encased in prodelta and shelf mudstones. An updip porosity pinch-out coincides with a gentle undulation on a uniformly gulfward-dipping monocline and forms a structurally modified stratigraphic trap. The reservoir is relatively tight and has an average porosity of 21% and average permeability of 6 md; wells require fracturing to stimulate production. Ultimate recovery, based on current production trends and technology, is projected to be 57 million bbl, or 29% of the 198 million bbl field. 24 figures, 1 table.

  2. Glacier modeling in support of field observations of mass balance at South Cascade Glacier, Washington, USA

    USGS Publications Warehouse

    Josberger, Edward G.; Bidlake, William R.

    2010-01-01

    The long-term USGS measurement and reporting of mass balance at South Cascade Glacier was assisted in balance years 2006 and 2007 by a new mass balance model. The model incorporates a temperature-index melt computation and accumulation is modeled from glacier air temperature and gaged precipitation at a remote site. Mass balance modeling was used with glaciological measurements to estimate dates and magnitudes of critical mass balance phenomena. In support of the modeling, a detailed analysis was made of the "glacier cooling effect" that reduces summer air temperature near the ice surface as compared to that predicted on the basis of a spatially uniform temperature lapse rate. The analysis was based on several years of data from measurements of near-surface air temperature on the glacier. The 2006 and 2007 winter balances of South Cascade Glacier, computed with this new, model-augmented methodology, were 2.61 and 3.41 mWE, respectively. The 2006 and 2007 summer balances were -4.20 and -3.63 mWE, respectively, and the 2006 and 2007 net balances were -1.59 and -0.22 mWE. PDF version of a presentation on the mass balance of South Cascade Glacier in Washington state. Presented at the American Geophysical Union Fall Meeting 2010.

  3. High-resolution local magnetic field models for the Martian South Pole from Mars Global Surveyor data

    NASA Astrophysics Data System (ADS)

    Plattner, A.; Simons, F. J.

    2015-09-01

    We present two high-resolution local models for the crustal magnetic field of the Martian south polar region. Models SP130 and SP130M were derived from three-component measurements made by Mars Global Surveyor at nighttime and at low altitude (<200 km). The availability area for these data covers the annulus between latitudes -76° and -87° and contains a strongly magnetized region (southern parts of Terra Sirenum) adjacent to weakly magnetized terrains (such as Prometheus Planum). Our localized field inversions take into account the region of data availability, a finite spectral bandlimit (spherical harmonic degree L = 130), and the varying satellite altitude at each observation point. We downward continue the local field solutions to a sphere of Martian polar radius 3376 km. While weakly magnetized areas in model SP130 contain inversion artifacts caused by strongly magnetized crust nearby, these artifacts are largely avoided in model SP130M, a mosaic of inversion results obtained by independently solving for the fields over individual subregions. Robust features of both models are magnetic stripes of alternating polarity in southern Terra Sirenum that end abruptly at the rim of Prometheus Planum, an impact crater with a weak or undetectable magnetic field. From a prominent and isolated dipole-like magnetic feature close to Australe Montes, we estimate a paleopole with a best fit location at longitude 207° and latitude 48°. From the abruptly ending magnetic field stripes, we estimate average magnetization values of up to 15 A/m.

  4. Floating production platforms and their applications in the development of oil and gas fields in the South China Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Dagang; Chen, Yongjun; Zhang, Tianyu

    2014-03-01

    This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A detailed review of current deepwater platforms worldwide was performed through the examples of industry projects, and the pros and cons of each platform are discussed. Four types of platforms are currently used for the deepwater development: tension leg platform, Spar, semi-submersible platform, and the floating production system offloading. Among these, the TLP and Spar can be used for dry tree applications, and have gained popularity in recent years. The dry tree application enables the extension of the drilling application for fixed platforms into floating systems, and greatly reduces the cost and complexity of the subsea operation. Newly built wet tree semi-submersible production platforms for ultra deepwater are also getting their application, mainly due to the much needed payload for deepwater making the conversion of the old drilling semi-submersible platforms impossible. These platforms have been used in different fields around the world for different environments; each has its own advantages and disadvantages. There are many challenges with the successful use of these floating platforms. A lot of lessons have been learned and extensive experience accumulated through the many project applications. Key technologies are being reviewed for the successful use of floating platforms for field development, and potential future development needs are being discussed. Some of the technologies and experience of platform applications can be well used for the development of the South China Sea oil and gas field.

  5. Comparison of LANDSAT-2 and field spectrometer reflectance signatures of south Texas rangeland plant communities

    NASA Technical Reports Server (NTRS)

    Richardson, A. J.; Escobar, D. E.; Gausman, H. W.; Everitt, J. H. (Principal Investigator)

    1982-01-01

    The accuracy was assessed for an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the LANDSAT satellite multispectral scanner (MSS) and a ground based spectroradiometer. The rangeland plant reflectances produced by the two sensors were correlated with no significant deviation of the slope from unity or of the intercept from zero. These results indicated that the atmospheric correction produced LANDSAT MSS estimates of rangeland plant reflectances that are as accurate as the ground based spectroradiometer.

  6. Normal incidence measurement in a subaqueous sand dune field in the South China Sea.

    PubMed

    Chiu, Linus Y S; Chang, Andrea Y Y

    2014-11-01

    Regions with subaqueous sand dunes have been discovered on the upper continental slope of the northern South China Sea. These large subaqueous sand dunes are expected to cause errors in the measurement of normal incidence reflection. This letter presents experiment results of two normal incidence survey tracks conducted in 2013, and the errors in reflection coefficient estimation and the resulting sediment properties induced by sand dune bedforms. The results demonstrate that the reflected energy is focused and scattered by different parts of sand dune bedforms and that they produce significant variation in the estimated reflection coefficients and the inverted geoacoustic properties.

  7. Effects of CRP field age and cover type on ring-necked pheasants in eastern South Dakota

    USGS Publications Warehouse

    Eggebo, S.L.; Higgins, K.F.; Naugle, D.E.; Quamen, F.R.

    2003-01-01

    Loss of native grasslands to tillage has increased the importance of Conservation Reserve Program (CRP) grasslands to maintain ring-necked pheasant (Phasianus colchicus) populations. Despite the importance of CRP to pheasants, little is known about the effects of CRP field age and cover type on pheasant abundance and productivity in the northern Great Plains. Therefore, we assessed effects of these characteristics on pheasant use of CRP fields. We stratified CRP grasslands (n=42) by CRP stand age (old [10-13 yrs] vs. new [1-3 yrs] grasslands) and cover type (CP1 [cool-season grasslands] vs. CP2 [warm-season grasslands]) in eastern South Dakota and used crowing counts and roadside brood counts to index ring-necked pheasant abundance and productivity. Field-age and cover-type effects on pheasant abundance and productivity were largely the result of differences in vegetation structure among fields. More crowing pheasants were recorded in old cool-season CRP fields than any other age or cover type, and more broods were recorded in cool- than warm-season CRP fields. Extending existing CRP contracts another 5-10 years would provide the time necessary for new fields to acquire the vegetative structure used most by pheasants without a gap in habitat availability. Cool-season grass-legume mixtures (CP1) that support higher pheasant productivity should be given equal or higher ratings than warm-season (CP2) grass stands. We also recommend that United States Department of Agriculture administrators and field staff provide broader and more flexible guidelines on what seed mixtures can be used in CRP grassland plantings in the northern Great Plains. This would allow landowners and natural resource professionals who manage pheasant habitat to plant a mosaic of cool- and warm-season CRP grassland habitats.

  8. z {approx} 7 GALAXY CANDIDATES FROM NICMOS OBSERVATIONS OVER THE HDF-SOUTH AND THE CDF-SOUTH AND HDF-NORTH GOODS FIELDS

    SciTech Connect

    Bouwens, Rychard J.; Illingworth, Garth D.; Gonzalez, Valentino; Holden, Brad; Magee, Dan; Labbe, Ivo; Franx, Marijn; Conselice, Christopher J.; Blakeslee, John; Van Dokkum, Pieter; Marchesini, Danilo; Zheng Wei

    2010-12-20

    We use {approx}88 arcmin{sup 2} of deep ({approx}>26.5 mag at 5{sigma}) NICMOS data over the two GOODS fields and the HDF-South to conduct a search for bright z {approx}> 7 galaxy candidates. This search takes advantage of an efficient preselection over 58 arcmin{sup 2} of NICMOS H{sub 160}-band data where only plausible z {approx}> 7 candidates are followed up with NICMOS J{sub 110}-band observations. {approx}248 arcmin{sup 2} of deep ground-based near-infrared data ({approx}>25.5 mag, 5{sigma}) are also considered in the search. In total, we report 15 z{sub 850}-dropout candidates over this area-7 of which are new to these search fields. Two possible z {approx} 9 J{sub 110}-dropout candidates are also found, but seem unlikely to correspond to z {approx} 9 galaxies (given the estimated contamination levels). The present z {approx} 9 search is used to set upper limits on the prevalence of such sources. Rigorous testing is undertaken to establish the level of contamination of our selections by photometric scatter, low-mass stars, supernovae, and spurious sources. The estimated contamination rate of our z {approx} 7 selection is {approx}24%. Through careful simulations, the effective volume available to our z {approx}> 7 selections is estimated and used to establish constraints on the volume density of luminous (L*{sub z{sub ={sub 3}}}, or {approx}-21 mag) galaxies from these searches. We find that the volume density of luminous star-forming galaxies at z {approx} 7 is 13{sup +8}{sub -5} times lower than at z {approx} 4 and >25 times lower (1{sigma}) at z {approx} 9 than at z {approx} 4. This is the most stringent constraint yet available on the volume density of {approx}>L*{sub z{sub ={sub 3}}} galaxies at z {approx} 9. The present wide-area, multi-field search limits cosmic variance to {approx}<20%. The evolution we find at the bright end of the UV LF is similar to that found from recent Subaru Suprime-Cam, HAWK-I or ERS WFC3/IR searches. The present paper also

  9. Seismogenic stress field estimation in the Calabrian Arc region (south Italy) from a Bayesian approach

    NASA Astrophysics Data System (ADS)

    Totaro, C.; Orecchio, B.; Presti, D.; Scolaro, S.; Neri, G.

    2016-09-01

    A new high-quality waveform inversion focal mechanism database of the Calabrian Arc region has been compiled by integrating 292 mechanisms selected from literature and catalogs with 146 newly computed solutions. The new database has then been used for computation of posterior density distributions of stress tensor components by a Bayesian method never applied in south Italy before the present study. The application of this method to the enhanced database has allowed us to provide a detailed picture of seismotectonic stress regimes in this very complex area where lithospheric unit configuration and geodynamic engines are still strongly debated. Our results well constrain the extensional domain of Calabrian Arc and the compressional one of the southernmost Tyrrhenian Sea. In addition, previously undetected transcurrent regimes have been identified in the Ionian offshore. The new information released here will furnish useful tools and constraints for future geodynamic investigations.

  10. Applications of exploration technologies to reservoir prediction and management -- Field examples of South-East Asia

    SciTech Connect

    Duval, B.C.; Allen, G.; Madaoui, K.; Gouadain, J.; Kremer, Y.

    1995-10-01

    The paper describes how modern geoscience techniques, developed for a large part in intensive exploration programs, can be used at the field level to improve reservoir prediction and production planning and also to optimize recovery. Detailed sedimentological studies has allowed the authors to determine the environment of the reservoir formations and help define the likely shape and size of individual sands and refine the reservoir model. An illustration is given by fields located in the Mahakam delta area of Kalimantan (Handil, Tunu) and in the Gulf of Thailand (Bongkot). Sequence stratigraphy assists in identifying efficient regional seals which, at field scale, lead to the recomposition of a great number of individual sands (several hundreds in some cases) into fewer flow units, making the system manageable from a reservoir standpoint. This technology was used extensively to delineate the giant Peciko gas field of Indonesia. The geophysical approach of reservoir parameters and the use of seismic attributes are rapidly expanding. The Yadana gas field in the Gulf of Martaban (Myanmar) is a case in point to show how porosities can be determined from impedances obtained by seismic inversion techniques. An example from the Bongkot field shows how 3D seismic and direct hydrocarbon indication technology (DHI) are used to deal with complex faulting to optimize deviated well profiles and improve recoveries.

  11. Candidate Clusters of Galaxies at z > 1.3 Identified in the Spitzer South Pole Telescope Deep Field Survey

    NASA Astrophysics Data System (ADS)

    Rettura, A.; Martinez-Manso, J.; Stern, D.; Mei, S.; Ashby, M. L. N.; Brodwin, M.; Gettings, D.; Gonzalez, A. H.; Stanford, S. A.; Bartlett, J. G.

    2014-12-01

    We present 279 galaxy cluster candidates at z > 1.3 selected from the 94 deg2 Spitzer South Pole Telescope Deep Field (SSDF) survey. We use a simple algorithm to select candidate high-redshift clusters of galaxies based on Spitzer/IRAC mid-infrared data combined with shallow all-sky optical data. We identify distant cluster candidates adopting an overdensity threshold that results in a high purity (80%) cluster sample based on tests in the Spitzer Deep, Wide-Field Survey of the Boötes field. Our simple algorithm detects all three 1.4 < z <= 1.75 X-ray detected clusters in the Boötes field. The uniqueness of the SSDF survey resides not just in its area, one of the largest contiguous extragalactic fields observed with Spitzer, but also in its deep, multi-wavelength coverage by the South Pole Telescope (SPT), Herschel/SPIRE, and XMM-Newton. This rich data set will allow direct or stacked measurements of Sunyaev-Zel'dovich effect decrements or X-ray masses for many of the SSDF clusters presented here, and enable a systematic study of the most distant clusters on an unprecedented scale. We measure the angular correlation function of our sample and find that these candidates show strong clustering. Employing the COSMOS/UltraVista photometric catalog in order to infer the redshift distribution of our cluster selection, we find that these clusters have a comoving number density nc = (0.7+6.3-0.6) × 10-7 h3 {Mpc}-3 and a spatial clustering correlation scale length r 0 = (32 ± 7) h -1 Mpc. Assuming our sample is comprised of dark matter halos above a characteristic minimum mass, M min, we derive that at z = 1.5 these clusters reside in halos larger than Mmin = 1.5+0.9-0.7 × 1014 h-1 M⊙ . We find that the mean mass of our cluster sample is equal to Mmean = 1.9+1.0-0.8 × 1014 h-1 M⊙ ; thus, our sample contains the progenitors of present-day massive galaxy clusters.

  12. CANDIDATE CLUSTERS OF GALAXIES AT z > 1.3 IDENTIFIED IN THE SPITZER SOUTH POLE TELESCOPE DEEP FIELD SURVEY

    SciTech Connect

    Rettura, A.; Stern, D.; Martinez-Manso, J.; Gettings, D.; Gonzalez, A. H.; Mei, S.; Ashby, M. L. N.; Brodwin, M.; Stanford, S. A.; Bartlett, J. G.

    2014-12-20

    We present 279 galaxy cluster candidates at z > 1.3 selected from the 94 deg{sup 2} Spitzer South Pole Telescope Deep Field (SSDF) survey. We use a simple algorithm to select candidate high-redshift clusters of galaxies based on Spitzer/IRAC mid-infrared data combined with shallow all-sky optical data. We identify distant cluster candidates adopting an overdensity threshold that results in a high purity (80%) cluster sample based on tests in the Spitzer Deep, Wide-Field Survey of the Boötes field. Our simple algorithm detects all three 1.4 < z ≤ 1.75 X-ray detected clusters in the Boötes field. The uniqueness of the SSDF survey resides not just in its area, one of the largest contiguous extragalactic fields observed with Spitzer, but also in its deep, multi-wavelength coverage by the South Pole Telescope (SPT), Herschel/SPIRE, and XMM-Newton. This rich data set will allow direct or stacked measurements of Sunyaev-Zel'dovich effect decrements or X-ray masses for many of the SSDF clusters presented here, and enable a systematic study of the most distant clusters on an unprecedented scale. We measure the angular correlation function of our sample and find that these candidates show strong clustering. Employing the COSMOS/UltraVista photometric catalog in order to infer the redshift distribution of our cluster selection, we find that these clusters have a comoving number density n{sub c}=(0.7{sub −0.6}{sup +6.3})×10{sup −7} h{sup 3} Mpc{sup −3} and a spatial clustering correlation scale length r {sub 0} = (32 ± 7) h {sup –1} Mpc. Assuming our sample is comprised of dark matter halos above a characteristic minimum mass, M {sub min}, we derive that at z = 1.5 these clusters reside in halos larger than M{sub min}=1.5{sub −0.7}{sup +0.9}×10{sup 14} h{sup −1} M{sub ⊙}. We find that the mean mass of our cluster sample is equal to M{sub mean}=1.9{sub −0.8}{sup +1.0}×10{sup 14} h{sup −1} M{sub ⊙}; thus, our sample contains the progenitors of

  13. Trace organic contaminants, including toxaphene and trifluralin, in cotton field soils from Georgia and South Carolina, USA.

    PubMed

    Kannan, K; Battula, S; Loganathan, B G; Hong, C S; Lam, W H; Villeneuve, D L; Sajwan, K; Giesy, J P; Aldous, K M

    2003-07-01

    Residues of organic contaminants--including toxaphene, DDT, trifluralin, hexachlorocyclohexanes, polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs) and nonylphenol--were measured in 32 cotton field soils collected from South Carolina and Georgia in 1999. Toxaphene, trifluralin, DDT and PAHs were the major contaminants found in these soils. The maximum concentration of toxaphene measured was 2,500 ng/g dry weight. Trifluralin was detected in all the soils at concentrations ranging from 1 to 548 ng/g dry weight. Pesticide residues were not proportional to soil organic carbon content, indicating that their concentrations were a reflection of application history and dissipation rates rather than air-soil equilibrium. Soil extracts were also subjected to in vitro bioassays to assess dioxinlike, estrogenic, and androgenic/glucocorticoid potencies. Relatively more polar fractions of the soils elicited estrogenic and androgenic/glucocorticoid activities, but the magnitude of response was much less than those found in coastal marine sediments from industrialized locations.

  14. Deep X-ray spectroscopy of high-z obscured AGN in the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Comastri, Andrea; Vignali, Cristian; Gilli, Roberto; Iwasawa, Kazushi; Georgantopoulos, Ioannis

    2012-07-01

    According to the recent models for the joint evolution of Super Massive Black Holes and their Host Galaxies, heavy obscuration represents an important phase and is expected to play a key role in the feedback mechanisms self regulating the SMBH growth. The smoking gun signature of heavy absorption is the presence of a heavily absorbed or reflected X-ray spectrum plus a strong Iron line. X-ray spectroscopy thus represents the most efficient method to uncover the most obscured sources. I will present the results of a systematic search for strong iron lines in the ultra-deep (3 Ms) XMM survey in the Chandra Deep Field South (CDFS). I will also highlight the power of deep spectroscopy to obtain redshift estimates more accurate and reliable than available photo-z. Some notable examples of synergies between ultra-deep Chandra (4 Ms) and XMM observations will be also reported.

  15. Water quality improvement by natural plant-mineral composites and field temperatures of a eutrophic lake in South Korea.

    PubMed

    Jung-Hwan, Byung; Kim, Ha-Kyung; Mun, Sun-Ki; Kim, Baik-Ho

    2014-09-01

    To improve the water quality of Shingal Reservoir, a eutrophic lake in South Korea, field tests were performed to assess the influence of water temperature on water quality improvement (WQI) ability of domestic plant-mineral composites (PMCs). Interestingly, Cyanobacterium was found to be dominant even in low-temperature seasons, especially winter leading to more effective for diatom growth. Factors such as phytoplankton, biological oxygen demand (BOD) and phosphorous showed high WQI over 70% at 20 degrees C, but declined to 40% at temperatures above 25 degrees C. WQI for Cyanobacteria decreased with increasing water temperature, whereas for diatoms WQI was 90% regardless of water temperature. Additionally, bacterial density and total nitrogen showed very low WQI without water temperature. Collectively, the results indicate that high water temperature decreased WQI ability of a PMC to control phytoplankton (Microcystis aeruginosa) and increased their ability to control diatoms.

  16. Mapping rainfall fields and their ENSO variation in data-sparse tropical south-west Pacific Ocean region

    NASA Astrophysics Data System (ADS)

    Basher, Reid E.; Zheng, Xiaogu

    1998-03-01

    Rainfall fields for the data-sparse tropical south-west Pacific Ocean region have been mapped by partial thin-plate smoothing spline surface modelling applied to island rainfall measurements, enhanced by the use of satellite observations of outgoing longwave radiation (OLR) as a regression covariate. The aim is to obtain spatially realistic rainfall maps, especially in the data-sparse areas between island groups, through a fully objective and statistically valid method that includes error estimates. The method has been applied to the region 4°N-24°S, 168°E-154°W. The rainfall data set initially comprised 57 stations, most with 40 year records. As a first step, a regression of annual OLR and rainfall for atolls only was formed and used to eliminate outlier rainfall stations, all of which are on mountainous islands and thus are probably influenced orographically.The maps clearly show the spatial patterns and seasonal behaviour of the regions key meteorological features, namely, the South Pacific Convergence Zone (SPCZ), the southern edge of the Inter-tropical Convergence Zone (ITCZ), and the wedge shaped region of divergent easterlies lying between them. To identify ENSO variations, maps of 3-month seasonal rainfall were constructed from composites of eight El Niño (negative SOI) episodes and nine La Niña (positive SOI) episodes. These maps are relatively rough in appearance, but nevertheless they show the evolution of the spatial patterns through each composite episode and the strong and symmetrically opposite differences between them. Marked variations in the strength and position of the SPCZ are evident and the isohyets in the equatorial dry zone exhibit east-west shifts of nearly 3000 km relative to the average field. The rainfall variation at a particular location may be understood in terms of competition of influence among the changing features of the pattern, rather than as a simple linear function of the SOI.

  17. A new South American network to study the atmospheric electric field and its variations related to geophysical phenomena

    NASA Astrophysics Data System (ADS)

    Tacza, J.; Raulin, J.-P.; Macotela, E.; Norabuena, E.; Fernandez, G.; Correia, E.; Rycroft, M. J.; Harrison, R. G.

    2014-12-01

    In this paper we present the capability of a new network of field mill sensors to monitor the atmospheric electric field at various locations in South America; we also show some early results. The main objective of the new network is to obtain the characteristic Universal Time diurnal curve of the atmospheric electric field in fair weather, known as the Carnegie curve. The Carnegie curve is closely related to the current sources flowing in the Global Atmospheric Electric Circuit so that another goal is the study of this relationship on various time scales (transient/monthly/seasonal/annual). Also, by operating this new network, we may also study departures of the Carnegie curve from its long term average value related to various solar, geophysical and atmospheric phenomena such as the solar cycle, solar flares and energetic charged particles, galactic cosmic rays, seismic activity and specific meteorological events. We then expect to have a better understanding of the influence of these phenomena on the Global Atmospheric Electric Circuit and its time-varying behavior.

  18. Local Lunar Gravity Field Analysis over the South Pole-aitken Basin from SELENE Farside Tracking Data

    NASA Technical Reports Server (NTRS)

    Goossens, Sander Johannes; Ishihara, Yoshiaki; Matsumoto, Koji; Sasaki, Sho

    2012-01-01

    We present a method with which we determined the local lunar gravity field model over the South Pole-Aitken (SPA) basin on the farside of the Moon by estimating adjustments to a global lunar gravity field model using SELENE tracking data. Our adjustments are expressed in localized functions concentrated over the SPA region in a spherical cap with a radius of 45deg centered at (191.1 deg E, 53.2 deg S), and the resolution is equivalent to a 150th degree and order spherical harmonics expansion. The new solution over SPA was used in several applications of geophysical analysis. It shows an increased correlation with high-resolution lunar topography in the frequency band l = 40-70, and admittance values are slightly different and more leveled when compared to other, global gravity field models using the same data. The adjustments expressed in free-air anomalies and differences in Bouguer anomalies between the local solution and the a priori global solution correlate with topographic surface features. The Moho structure beneath the SPA basin is slightly modified in our solution, most notably at the southern rim of the Apollo basin and around the Zeeman crater

  19. Models of Active Glacial Isostasy Roofing Warm Subduction: Case of the South Patagonian Ice Field

    NASA Technical Reports Server (NTRS)

    Klemann, Volker; Ivins, Erik R.; Martinec, Zdenek; Wolf, Detlef

    2007-01-01

    Modern geodetic techniques such as precise Global Positioning System (GPS) and high-resolution space gravity mapping (Gravity Recovery and Climate Experiment, GRACE) make it possible to measure the present-day rate of viscoelastic gravitational Earth response to present and past glacier mass changes. The Andes of Patagonia contain glacial environments of dramatic mass change. These mass load changes occur near a tectonically active boundary between the Antarctic and South American plates. The mechanical strength of the continental side of this boundary is influenced by Neogene ridge subduction and by the subduction of a youthful oceanic slab. A ridge of young volcanos parallels the Pacific coastline. Release of volatiles (such as water) at depth along this ridge creates a unique rheological environment. To assess the influence of this rheological ridge structure on the observational land uplift rate, we apply a two dimensional viscoelastic Earth model. A numerical study is presented which examines the sensitivity of the glacial loading-unloading response to the complex structure at depth related to the subducting slab, the viscous wedge between slab and continental lithosphere, and the increase of elastic thickness from oceanic to continental lithosphere. A key feature revealed by our numerical experiments is a continuum flow wherein the slab subdues the material transport toward oceanic mantle and crust. The restricted flow is sensitive to the details of slab mechanical strength and penetration into the upper mantle. The reduced viscosity within the mantle wedge, however, enhances the load-induced material transport everywhere within the asthenosphere.

  20. Validation of in situ networks via field sampling: case study in the South Fork Experimental Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The calibration and validation of soil moisture remote sensing products is complicated by the logistics of installing a soil moisture network for a long term period in an active landscape. Therefore, these stations are located along field boundaries or in non-representative sites with regards to so...

  1. Petrology and depositional environment of Sunniland producing fields of south Florida

    SciTech Connect

    Mitchell-Tapping, H.J.

    1984-09-01

    Oil exploration began in Florida in 1901, but no oil was found until 1943. In November of that year, Humble Oil and Refining Co. made a discovery near Sunniland in southern Florida. This field and the producing zone were called Sunniland. No further discoveries were made in southern Florida until 1954 when the Forty-Mile field was discovered by Gulf Oil Co. Ten years later, in 1964, the Sunoco Felda field was discovered by Sun Oil Co., followed by West Sunoco Felda field in 1968. The examination of numerous cores and thin sections of this formation, both from producing fields and wildcat wells, reveals a sequence of deposition in the Sunniland formation. It has been reported that tintinnids or calpionellids have been observed in the lower mud section, but investigation of many thin sections from this section revealed only ostracod particles. Above the mudstone, the section becomes increasingly plentiful in fragmented microbored rudist particles and forams such as Orbitolina texana, Dictyoconus floridanus, and Coskinolina sunnilandensis. Above this section the sequence is considered regressive and consists of pellets and forams with a few mollusk fragments. This section is interpreted as the basal unit of a grainstone bar shoal. The grainstone bar shoal is made up of reworked particles of oysters (Texigryphea), coated caprinid fragments, forams, and echinoid fragments. For some years, the rocks of the Sunniland formation have been considered reefal, but based on the results of this study, these rocks are interpreted to be a barrier tidal-shoal bar deposited well behind the main reef crest, which lies farther offshore at the edge of the Florida escarpment.

  2. Statistical scaling, Shannon entropy, and Generalized space-time q-entropy of rainfall fields in tropical South America.

    PubMed

    Poveda, Germán; Salas, Hernán D

    2015-07-01

    We study diverse scaling and information theory characteristics of Mesoscale Convective Systems (MCSs) as seen by the Tropical Rainfall Measuring Mission (TRMM) over continental and oceanic regions of tropical South America, and 2-D radar rainfall fields from Amazonia. The bi-dimensional Fourier spectra of MCSs exhibit inverse power laws with respect to the spatial scale, whose scaling exponents, β, capture the type of spatial correlation of rainfall among the study regions, including those over the Andes of Colombia as well as over oceanic and Amazonian regions. The moment-scaling analysis evidences that the structure function deviates from simple scaling at order q > 1.0, thus signaling the multi-scaling nature of rainfall fields within MCSs in tropical South America, with departures from simple scaling associated with the physical characteristics of MCSs over the different study regions. Entropy is estimated for a large set of radar rainfall fields during the distinctive atmospheric regimes (Easterly and Westerly events) in this part of Amazonia. Results evidence that there are significant differences in the dynamics of rainfall among regimes. No clear-cut relationship is found between entropy and the first two statistical moments, but power fits in space and time, S(γ) ∼ γ(-η) for skewness and, S(κ) ∼ κ(-ϵ) for kurtosis. The exponents η and ϵ are statistically different between Easterly and Westerly events, although the significance of fits is less when L-moments are used to estimate skewness and kurtosis. Interesting differences are identified between the time and space generalized q-entropy functions of Amazonian rainfall fields. In both cases, the functions are a continuous set of power laws (analogous to the structure function in turbulence), S(T, q) ∼ T(β), and, S(λ, q) ∼ λ(β), covering a broad range of temporal and spatial scales. Both time and space generalized q-entropy functions exhibit linear growth in the

  3. Prevalence and management status of urologic diseases in geriatric hospitals in South Korea: A field research

    PubMed Central

    Lee, Sang Heon; Suh, Jungyo; Kim, Hyung Suk; Lee, Young Ju; Lee, Sang Rim; Kim, Khae Hawn

    2017-01-01

    Purpose We aimed to investigate the current management status of urologic diseases in geriatric hospitals in South Korea. Materials and Methods Questionnaire surveys and in-depth person-to-person interviews were conducted at 13 hospitals within the Seoul and Incheon areas. Results The study was carried out from July to December 2014; 75.6% of patients (1,858/2,458) and 77.5% (779/1,031) of medical personnel responded to our survey. All surveys and interviews were performed by urology specialists, fellows, residents, or nurses. The hospitals included in the study had an average of 215.2 beds (range, 110–367), 189.1 patients (range, 90–345), and 40.2 nurses (range, 10–83). The average number of physicians was 6.2 (range, 3–11), but none of these were certified urologists. Only 4 hospitals provided consultation services for urological disorders. In total, 64% of patients had urological disorders, although only 20.7% of patients were receiving medication. Most patients were being treated using urological interventions; diapers (49.7%), indwelling catheters (19.5%), clean intermittent catheters (12.2%), and external collection urinary drainage (7.9%). However, most interventions were inadequately implemented, and only 17% of the patients had been examined by a certified urologist. Urological complications were found in 20.2% of patients, and secondary complications occurred in 18.8%. Excluding redundant cases, the total prevalence of urological complications was 39.0%. Conclusions Urologic diseases are poorly managed, and no certified urologists work in geriatric hospitals. Therefore, more designated urologists are needed in geriatric hospitals. PMID:28097271

  4. Turtle Bayou - 1936 to 1983: case history of a major gas field in south Louisiana

    SciTech Connect

    Cronquist, C.

    1983-01-01

    Turtle Bayou field, located in the middle Miocene trend in S. Louisiana, is nearing the end of a productive life which spans over 30 yr. Discovered by Shell Oil Co. in 1949 after unsuccessful attempts by 2 other majors, the field is a typical, low relief, moderately faulted Gulf Coast structure, probably associated with deep salt movement. The productive interval includes 22 separate gas-bearing sands in a regressive sequence of sands and shales from approx. 6500 to 12,000 ft. Now estimated to have contained ca 1.2 trillion scf of gas in place, cumulative production through 1982 was 702 billion scf. Cumulative condensate-gas ratio has been 20 bbl/million. Recovery mechanisms in individual reservoirs include strong bottom water drive, partial edgewater drive, and pressure depletion. Recovery efficiencies in major reservoirs range from 40 to 75% of original gas in place.

  5. Validation of in Situ Networks Via Field Sampling: Case Study in the South Fork Experimental Watershed

    NASA Astrophysics Data System (ADS)

    Cosh, M. H.; McKee, L.; Bindlish, R.; Coopersmith, E. J.; Jackson, T. J.; Prueger, J. H.

    2014-12-01

    The calibration and validation of soil moisture remote sensing products is complicated by the logistics of installing a soil moisture network for a long term period in an active landscape. Therefore, these stations are located along field boundaries or in non-representative sites with regards to soil type or soil moisture. The representative character of this network can only be established by large scale field sampling to provide a calibration dataset. A team of samplers were deployed twice a week for the summer of 2014 to collect surface soil moisture data across a variety of land covers at 44 sites. These samples were compared and scaled to the domain to get a better understanding of the large scale soil moisture distributions and dynamics. In addition, comparisons are made to the Soil Moisture Ocean Salinity (SMOS) soil moisture product for the length of the network installation.

  6. Core facies, petrology, and permeability of Tirrawarra Sandstone, Moorari Field, Cooper Basin, South Australia

    SciTech Connect

    Bever, J.M.; Carroll, P.G.; Wild, E.W.; Williams, B.P.J.

    1988-01-01

    The oil and gas-bearing Tirrawarra Sandstone lies in the basal section of the Cooper basin sequence, which is largely Permian in age. The sandstone is characteristically thick, but both interfingers with and conformable overlies glacio-lacustrine diamictites and varvites of the late Carboniferous-Early Permian Merrimeleia Formation. The Tirrawarra Sandstone has previously been interpreted as being deposited in a glacio-fluvial braided river environment. The sandstone produces high gas:oil-ratio oil at the Moorari field, from depths of 9,400 ft below sea level. Appraisal and development of the field has been hampered by the patchy distribution of reservoir quality sandstone. This study investigated the cause of reservoir quality variations. For seven cored wells, core facies analysis, core plug porosity/permeability, petrology, and wireline logs were all matched and compared. The results are as follows. (1) Facies states (grain size and bed form) largely control permeability distribution in the Tirrawarra Sandstone at the Moorari field, such that horizontally bedded medium-coarse sandstones are consistently more permeable than cross-bedded equivalents. (2) Diagenesis levels are high and include extensive silica cement and patchy kaolinite and siderite cements. However, diagenesis rarely operates independently of original depositional fabric. (3) An association between depositional environment and permeability is recognizable, with medial bars in particular providing better reservoir quality.

  7. Effects of Season and Management of Irrigated Cotton Fields on Collembola (Hexapoda) in New South Wales, Australia.

    PubMed

    Lytton-Hitchins, James A; Greenslade, Penelope; Wilson, Lewis J

    2015-06-01

    The effects of production practices on the relative abundance of springtails (Collembola) in irrigated cotton fields of northern New South Wales (NSW) were studied over 2 yr to examine effects of farm management on these decomposer organisms. Pitfall trapping and soil core extraction was undertaken in both pseudoreplicated plots within whole fields on cotton farms and on experimental replicate plots of Envirofeast cotton and Lucerne. The relative abundance of surface-active springtails in cotton rows and densities of soil species from the rhizosphere were calculated. Twenty-three species of Collembola were collected from 5 fields, 19 in pitfall traps, and 11 in soil cores. Five species, Setogaster sp., Proisotoma minuta, Entomobrya unostrigata, Entomobrya multifasciata grp, and Lepidobrya sp. were numerically dominant on the ground at 86-96% of individuals and Mesaphorura sp., Folsomides parvulus, and Hemisotoma thermophila grp dominant in the soil. Native grassland samples contained 15 species of which a probable 10 were native and 8 were not found in cotton. Nineteen species of the 24 species identified from cotton were predominantly fungal feeders. Highest catches of Collembola occurred after flowering and soil Collembola increased with depth and during cotton growth on unsprayed plots but decreased on sprayed plots. Surface soil moistures affected daily catch rates with decomposing residues, crop stage, predator abundance, and season as secondary factors. Insecticide (endosulfan, pyrethroid, carbamate, and organophosphate) and predator effects were either negligible or unclear depending on the factor involved. Springtails appear to be predominately food limited during times of adequate soil moisture in cotton fields.

  8. Tolerance of nonindigenous cichlid fishes (Cichlasoma urophthalmus, Hemichromis letourneuxi) to low temperature: laboratory and field experiments in south Florida

    USGS Publications Warehouse

    Schofield, Pamela J.; Loftus, William F.; Kobza, Robert M.; Cook, Mark I.; Slone, Daniel H.

    2010-01-01

    The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.

  9. Surficial geology of the Safsaf region, south-central Egypt, derived from remote-sensing and field data

    USGS Publications Warehouse

    Davis, P.A.; Breed, C.S.; McCauley, J.F.; Schaber, G.G.

    1993-01-01

    We used a decorrelation-stretched image of Landsat Thematic Mapper (TM) Bands 1, 4, and 7 and field data to map and describe the main surficial units in the hyperarid Safsaf region in south-central Egypt. We show that the near-infrared bands on Landsat TM, which are sensitive to very subtle changes in mineralogy common to arid regions, significantly improve the geologist's capability to discriminate geologic units in desert regions. These data also provide the spatial and spectral information necessary to determine the migration patterns and provenance of eolian materials. The Safsaf area was the focus of our post flight field studies using Shuttle Imaging Radar (SIR) data following the discovery of buried paleochannels in North Africa. Most of the channels discernible on SIR images are not expressed in TM data, but traces of a few channels are present in both the SIR and the TM data within the Wadi Safsaf area. Here we present a detailed digital examination of the SIR and the TM-band reflectance and reflectance-ratio data at three locations of the more obvious surface expressions of the buried channels. Our results indicate that the TM expressions of the channels are not purely topographic but are more compositional in nature. Two possibilities may account for the TM expressions of the buried channels: 1) concentrations of windblown, iron-rich materials that accumulated along subtle curvilinear topograpohic traps, or 2) curvilinear exposures of an iron-rich underlying unit of the flat sand sheet. ?? 1993.

  10. VizieR Online Data Catalog: z>~5 AGN in Chandra Deep Field-South (Weigel+, 2015)

    NASA Astrophysics Data System (ADS)

    Weigel, A. K.; Schawinski, K.; Treister, E.; Urry, C. M.; Koss, M.; Trakhtenbrot, B.

    2015-09-01

    The Chandra 4-Ms source catalogue by Xue et al. (2011, Cat. J/ApJS/195/10) is the starting point of this work. It contains 740 sources and provides counts and observed frame fluxes in the soft (0.5-2keV), hard (2-8keV) and full (0.5-8keV) band. All object IDs used in this work refer to the source numbers listed in the Xue et al. (2011, Cat. J/ApJS/195/10) Chandra 4-Ms catalogue. We make use of Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) data from the Great Observatories Origins Deep Survey South (GOODS-south) in the optical wavelength range. We use catalogues and images for filters F435W (B), F606W (V), F775W (i) and 850LP (z) from the second GOODS/ACS data release (v2.0; Giavalisco et al., 2004, Cat. II/261). We use Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) Wide Field Camera 3 (WFC3)/infrared data from the first data release (DR1, v1.0) for passbands F105W (Y), F125W (J) and F160W (H) (Grogin et al., 2011ApJS..197...35G; Koekemoer et al., 2011ApJS..197...36K). To determine which objects are red, dusty, low-redshift interlopers, we also include the 3.6 and 4.5 micron Spitzer Infrared Array Camera (IRAC) channels. We use SIMPLE image data from the DR1 (van Dokkum et al., 2005, Spitzer Proposal, 2005.20708) and the first version of the extended SIMPLE catalogue by Damen et al. (2011, Cat. J/ApJ/727/1). (6 data files).

  11. Reservoir quality, sediment source, and regional aspects of Norphlet Formation, South State Line field, Greene County, Mississippi

    SciTech Connect

    Thomson, A.; Stancliffe, R.J.; Shew, R.D.

    1987-05-01

    South State Line field, discovered in 1970, is centrally located in the productive Jurassic Norphlet trend of the eastern Gulf Coast. The Norphlet Formation at South State Line has produced gas and condensate from normally pressured eolian sandstones at depths of more than 17,900 ft (5455 m). The 600-ft- (183-m) thick Norphlet Formation is composed of 100% sandstone and consists of two reservoir types: a poorer quality upper sandstone having low permeability (0.6 md) and a good-quality lower sandstone with better permeability (15.5 md). The upper sandstone exhibits tighter compaction of framework grains and more cement than the lower sandstone. Significantly, the upper sandstone contains authigenic illite (which promotes pressure solution), whereas the lower sandstone contains authigenic chlorite (which inhibits cementation and possibly pressure solution). On a regional scale, illite is the principal diagenetic clay mineral in the western area of the Norphlet trend (Mississippi to Texas), whereas chlorite is the principal diagenetic clay mineral in the east (Alabama to Florida). Not surprisingly, reservoir quality is poorer in the western portion of the trend. A comparison of framework grains in the upper and lower sandstones shows no significant compositional differences. Both are mature arkosic sandstones with a transitional-continental source (eastern Appalachians). No evidence was seen of a quartz-rich Ouachita or cratonic source. Volcanic and plutonic rock fragments are slightly more abundant in the lower sandstone, possibly reflecting a shifting of compositional terranes within a single source area along the eastern side of the Appalachians. The lower Norphlet sandstone may have been derived from Triassic volcanics, whereas the upper sandstone may have been derived from a more metamorphic source.

  12. A joint geophysical analysis of the Coso geothermal field, south-eastern California

    NASA Astrophysics Data System (ADS)

    Wamalwa, Antony M.; Mickus, Kevin L.; Serpa, Laura F.; Doser, Diane I.

    2013-01-01

    Three-dimensional density models derived from gravity data and two-dimensional resistivity models derived from magnetotelluric data collected in the vicinity of the Coso geothermal field are analyzed in order to determine the source region of the geothermal field. The derived models show zones of both low resistivity and low density at and below 6 km depth in the Devils Kitchen and the Coso Hot Springs areas. These zones agree with seismic reflection and tomography results which found a high amplitude reflector at 5 km and low velocities zones below 5 km. We interpret the density and resistivity zones to indicate the presence of cooling magmatic material that provides the heat for the shallower geothermal system in these regions. A zone marked by high resistivity and low density was found to lie directly above the interpreted partially melted region extending to within 1 km depth below the surface in the reservoir region where it is capped by a low resistivity clay zone. In addition, the density models indicate that the high density bodies occurring under volcanic outcrops may be mafic intrusions.

  13. A COMPREHENISVE NONPOINT SOURCE FIELD STUDY FOR SEDIMENT, NUTRIENTS AND PATHOGENS IN THE SOUTH FORK BROAD RIVER WATERSHED IN NORTHEAST GEORGIA

    EPA Science Inventory

    There is an urgent need for EPA to develop protocols for establishing Total Maximum Daily Loads (TMDLs) in streams, lakes and estuaries. A cooperative TMDL field data collection project between ORD and Region 4 is ongoing in the South Fork Broad River Watershed (SFBR), a 245.18 ...

  14. Multiproxy summer and winter surface air temperature field reconstructions for southern South America covering the past centuries

    NASA Astrophysics Data System (ADS)

    Neukom, R.; Luterbacher, J.; Villalba, R.; Küttel, M.; Frank, D.; Jones, P. D.; Grosjean, M.; Wanner, H.; Aravena, J.-C.; Black, D. E.; Christie, D. A.; D'Arrigo, R.; Lara, A.; Morales, M.; Soliz-Gamboa, C.; Srur, A.; Urrutia, R.; von Gunten, L.

    2011-07-01

    We statistically reconstruct austral summer (winter) surface air temperature fields back to ad 900 (1706) using 22 (20) annually resolved predictors from natural and human archives from southern South America (SSA). This represents the first regional-scale climate field reconstruction for parts of the Southern Hemisphere at this high temporal resolution. We apply three different reconstruction techniques: multivariate principal component regression, composite plus scaling, and regularized expectation maximization. There is generally good agreement between the results of the three methods on interannual and decadal timescales. The field reconstructions allow us to describe differences and similarities in the temperature evolution of different sub-regions of SSA. The reconstructed SSA mean summer temperatures between 900 and 1350 are mostly above the 1901-1995 climatology. After 1350, we reconstruct a sharp transition to colder conditions, which last until approximately 1700. The summers in the eighteenth century are relatively warm with a subsequent cold relapse peaking around 1850. In the twentieth century, summer temperatures reach conditions similar to earlier warm periods. The winter temperatures in the eighteenth and nineteenth centuries were mostly below the twentieth century average. The uncertainties of our reconstructions are generally largest in the eastern lowlands of SSA, where the coverage with proxy data is poorest. Verifications with independent summer temperature proxies and instrumental measurements suggest that the interannual and multi-decadal variations of SSA temperatures are well captured by our reconstructions. This new dataset can be used for data/model comparison and data assimilation as well as for detection and attribution studies at sub-continental scales.

  15. Fluvial architecture and reservoir heterogeneity of middle Frio sandstones, Seeligson field, Jim Wells and Kleberg Counties, south Texas

    SciTech Connect

    Jirik, L.A.; Kerr, D.R.; Zinke, S.G.; Finley, R.J. )

    1990-05-01

    Evaluation of fluvial Frio reservoirs in south Texas reveals a complex architectural style potentially suited to the addition of incremental gas reserves through recognition of untapped compartments or bypassed gas zones. Seeligson field is being studied as part of a GRI/DOE/Texas-sponsored program, in cooperation with Oryx Energy Company and Mobil Exploration and Production U.S., Inc., and is designed to develop technologies and methodologies for increasing gas reserves from conventional reservoirs in mature fields. Seeligson field, discovered in 1937, has produced 2.2 tcf of gas from more than 50 middle Frio reservoirs. Cross sections as well as net sand and log facies maps illustrate depositional style, sandstone geometry, and reservoir heterogeneities. Far-offset vertical seismic profiles show laterally discontinuous reflections corresponding to the reservoirs. Lenticular lateral-bar sandstones dominate channel-fill deposits that together are commonly less than 50 ft thick, forming belts of sandstone approximately 2,500 ft wide. Crevasse-splay deposits commonly extend a few thousand feet beyond the channel system. Sand-rich channel-fill deposits are flanked by levee and overbank mudstones, isolating the reservoirs in narrow, dip-elongate trends. Deposition on an aggrading coastal plain resulted in a pattern of laterally stacked sandstone bodies that are widespread across the study area. Alternating periods of more rapid aggradation resulted in deposition of vertically stacked sandstones with limited areal distribution. Facies architecture of both depositional styles has implications for reservoir compartmentalization. Reservoir compartments within a laterally stacked system may be leaky, resulting from sandstone contact from producing wells along depositional axes. This effect is a major factor controlling incremental recovery. Reservoirs in vertically stacked systems should be better isolated.

  16. Constraints on primordial magnetic fields from Planck data combined with the South Pole Telescope CMB B -mode polarization measurements

    NASA Astrophysics Data System (ADS)

    Zucca, Alex; Li, Yun; Pogosian, Levon

    2017-03-01

    A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum. Indeed, vortical modes sourced by the PMF can dominate the B-mode power spectrum on small scales, as they survive damping up to a small fraction of the Silk length. Therefore, measurements of the B-mode polarization at high ℓ , such as the one recently performed by the South Pole Telescope (SPT), have the potential to provide stringent constraints on the PMF. We use the publicly released SPT B-mode polarization spectrum, along with the temperature and polarization data from the Planck satellite, to derive constraints on the magnitude, the spectral index and the energy scale at which the PMF was generated. We find that, while Planck data constrains the magnetic amplitude to B1 Mpc<3.3 nG at the 95% confidence level (C.L.), the SPT measurement improves the constraint to B1 Mpc<1.5 nG . The magnetic spectral index, nB, and the time of the generation of the PMF are unconstrained. For a nearly scale-invariant PMF, predicted by the simplest inflationary magnetogenesis models, the bound from Planck +SPT is B1 Mpc<1.2 nG at 95% C.L. For PMF with nB=2 , which is expected for fields generated in post-inflationary phase transitions, the 95% C.L. bound is B1 Mpc<0.002 nG , corresponding to the magnetic fraction of the radiation density ΩB γ<10-3 or the effective field Beff<100 nG . The patches for the Boltzmann code camb and the Markov chain Monte Carlo engine CosmoMC, incorporating the PMF effects on CMB, are made publicly available.

  17. Mantle xenocrysts of Chompolo field of the alkaline volcanics, Aldan shield, South Yakutia.

    NASA Astrophysics Data System (ADS)

    Nikolenko, Evgeny; Tychkov, Nikolay; Afanasiev, Valentin

    2015-04-01

    New mineralogical and chemical constraints for 10 dikes, veins (360-800m) and pipes (60-110 m) of Chompolo field discovered in 1957-1958 are discussed. Feld is located within Central Aldan Archean and Paleoproterozoic granulite-orthogneiss superterrane of Aldan-Stanovoy Shield, with peak of metamorphism - 2.1-1.9 Ga (Smelov, Timofeev, 2007). Originally (Shilina and Zeitlin 1959) and later (Kostrovitsky and Garanin 1992, Ashchepkov, Vladykin et al. 2001) these rocks were classified as kimberlites by mineralogy including pyrope, Cr spinel, and Cr diopside. Panina and Vladykin (1994), Davies et al, (2006) identified them as lamprophyres and lamproites. The age of Chompolo rocks is pre-Jurassic (Vladimirov et. al., 1989) dated by 40Ar/39Ar as 164.7±1 Ma (233.7±2.2 next plato)(unpublished Ashchepkov). The Rb-Sr isochron for lamprophyre "intrusions 104" indicate later age of 131±4 Ma (Zaitsev, Smelov, 2010). Magmatic bodies (Aldanskaya, Sputnik, Gornaya, Ogonek, Perevalnaya, Kilier-E) were studied during 2012-2013 fieldworks. Most of igneous rocks occur as inequigranular volcanic breccias with micro- or crypto-crystalline groundmass of K feldspar (up to 16.3 wt.% K2O, up to 3.2 wt.% FeO), chlorite, opaque minerals, melanocratic xenocrysts and phenocrysts (garnet, pyroxene, amphibole, Cr spinel, apatite, zircon, mica), and abundant xenogenic fragments of wallrock and crystalline basement. Garnet chemistry records the presence of mantle and crustal material. Mantle garnets lack the common megacryst, wehrlite, and high-temperature lherzolite varieties. Mantle mineralization prevails in the Aldan dike and the Sputnik, Gornaya, and Ogonek pipes, while crustal and elcogitic material is in the Perevalnaya and Kilier-E pipes. The Cr spinel consists of (in wt%) 3.5 to 50.9 Al2O3, 18.6-63.5 wt% Cr2O3, 6.1 to 19.1 MgO, and 0 to 1.61 TiO2. Al and Cr in spinels are in inverse proportion. The Chompolo alkaline volcanic rocks are most similar to the Central Aldan lamproites in trace

  18. Holocene records of geomagnetic field behavior from a north-south transect along the western Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Brachfeld, S. A.; Shah, D. P.; St-Onge, M.; St-Onge, G.

    2013-12-01

    Geochronology is inherently difficult when working with Antarctic margin sediments. Radiocarbon dating and oxygen isotope stratigraphy are challenging or impossible in sites with poor preservation of biogenic calcite. Radiocarbon dating of the acid insoluble organic matter (AIOM) is further complicated by organically lean sediment and the presence of reworked organic carbon or detrital carbon from sedimentary rocks. These complications limit the ability to interpret a paleoclimate record. Geomagnetic paleointensity dating is a proven 'tuning' technique that has been successfully applied in several studies around the Antarctic margin. However, the reference curves to which these sites were tuned were constructed primarily from Northern Hemisphere data. Here we present paleomagnetic secular variation (PSV) and relative paleointensity (RPI) data from three Antarctic Peninsula sites that possess independent chronologies and which have moderate to ultra-high sedimentation rates (40 - 700 cm/ka). Maxwell Bay, located in the volcanic South Shetland Islands, is an ultra-high-resolution site with strongly magnetic sediments from which the Shallow Drilling (SHALDRIL) program recovered a 108-m record spanning the last 14 ka. Outer Barilari Bay and Hugo Island Trough, which lie to the South along the western Antarctic Peninsula, are moderate resolution sites with a high proportion of biogenic silica. Maxwell Bay and Bariliari Bay are unique in that they possess homogenous sediment and uniform magnetic mineral assemblages, while also preserving biogenic calcite, a rare combination on the Antarctic margin. All three sites preserve strong, stable remanent magnetizations with an easily isolated characteristic component and MAD values generally < 2°, with the exception of turbidites, intervals with abundant dropstones, and biosiliceous ooze intervals. Inclination values fluctuate between the present-day value at the cores sites (-58°) and the geomagnetic axial dipole inclination

  19. Estimation of the recharge areas contributing water to the south well field, Columbus, Ohio

    USGS Publications Warehouse

    Schalk, C.W.; ,

    1996-01-01

    The city of Columbus, Ohio, operates four radial collector wells, designed to yield 42 Mgal/d (million gallons per day), in southern Franklin County, Ohio, as part of their municipal supply of water. The collector wells are adjacent to, and designed to induce infiltration from, Big Walnut Creek and Scioto River. A previously constructed, three-dimensional, steady-state and transient ground-water-flow model of this river-aquifer system was used to estimate contributing recharge areas (CRA's) and calculate particle flowpaths in southern Franklin County. The simulations were of two steady-state periods (October 1979 and March 1986) and one 5-year transient period (March 1986---June 1991). The first simulation (1979) was of conditions before construction of the collector wells. The second simulation (1986) was of conditions when the collector wells were producing 8 Mgal/d. During the 5 years covered in the transient simulation, production at the well field averaged 18.5 Mgal/d. Under the 1979 conditions, the largest ground-water contributing areas were of the quarries and Scioto River (41 and 47 percent of the study area, respectively). During 1986, when 8 Mgal/d was withdrawn, the primary contributing areas were of the quarries (40 percent), collector wells (34 percent), and rivers (8 percent). Travel times associated with simulated particles of water tracked from cells along Big Walnut Creek to their discharge points in cells along Scioto River were about 5 to 60 years in the 1979 simulation and about 7 to 41 years in the 1986 simulation. The endpoints of these particles varied as simulated pumping rates were increased to 22 Mgal/d. The 1986, 10-year CRA's of the collector wells under 8 Mgal/d-conditions totalled about 4.5 mi2. As the pumping rate was increased to 22 Mgal/d in a predictive simulation, 10-year CRA's of the collector wells increased to 6.7mi2. Because the transient simulation encompassed only 5 years, the 10-year CRA's could not be estimated from the

  20. Selected hydrologic data, Kolob-Alton-Kaiparowits coal-fields area, south-central Utah

    USGS Publications Warehouse

    Plantz, G.G.

    1983-01-01

    The Kolob-Alton-Kaiparowits coal field area includes about 4,500 sq mi in parts of the Colorado River Basin and the Great Basin. The area varies in altitude from < 4,000 to > 10,000 ft, and is comprised chiefly of plateaus, benches, and terraces that are dissected by deep, narrow canyons. Water quality was studied in principal streams draining the area, the Virgin, Sevier, Escalante, and Paria Rivers; and Coal, Kanab, and Wahweap Creeks. Most of the data included in this report were collected by the U.S. Geological Survey from October 1980 to September 1982, as part of a hydrologic study in cooperation with the U.S. Bureau of Land Management to evaluate potential impacts of coal mining on the area 's water resources. Data include: discharge, water temperature, specific conductance, and pH. Data collected from selected wells and springs include: specific conductance, pH, hardness, and dissolved quantities of calcium, magnesium, potassium, sodium, sulfates, chlorides, fluorides, silica, nitrogen, boron, iron, and manganese. (Lantz-PTT)

  1. GIS-based technology for marine geohazards in LW3-1 Gas Field of the South China Sea

    NASA Astrophysics Data System (ADS)

    Su, Tianyun; Liu, Lejun; Li, Xishuang; Hu, Guanghai; Liu, Haixing; Zhou, Lin

    2013-04-01

    The exploration and exploitation of deep-water oil-gas are apt to be suffered from high-risk geo-hazards such as submarine landslide, soft clay creep, shallow gas, excess pore-water pressure, mud volcano or mud diaper, salt dome and so on. Therefore, it is necessary to survey the seafloor topography, identify the unfavourable geological risks and investigate their environment and mechanism before exploiting the deep-water oil-gas. Because of complex environment, the submarine phenomenon and features, like marine geohazards, can not be recognized directly. Multi-disciplinary data are acquired and analysed comprehensively in order to get more clear understanding about the submarine processes. The data include multi-beam bathymetry data, sidescan sonar images, seismic data, shallow-bottom profiling images, boring data, etc.. Such data sets nowadays increase rapidly to large amounts, but may be heterogeneous and have different resolutions. It is difficult to make good management and utilization of such submarine data with traditional means. GIS technology can provide efficient and powerful tools or services in such aspects as spatial data management, processing, analysis and visualization. They further promote the submarine scientific research and engineering development. The Liwan 3-1 Gas Field, the first deep-water gas field in China, is located in the Zhu II Depression in the Zhujiang Basin along the continental slope of the northern South China Sea. The exploitation of this field is designed to establish subsea wellhead and to use submarine pipeline for the transportation of oil. The deep-water section of the pipeline route in the gas field is to be selected to pass through the northern continental slope of the South China Sea. To avoid huge economic loss and ecological environmental damage, it is necessary to evaluate the geo-hazards for the establishment and safe operation of the pipeline. Based on previous scientific research results, several survey cruises have

  2. STELLAR MASSES FROM THE CANDELS SURVEY: THE GOODS-SOUTH AND UDS FIELDS

    SciTech Connect

    Santini, P.; Fontana, A.; Castellano, M.; Grazian, A.; Amorin, R.; Ferguson, H. C.; Mobasher, B.; Barro, G.; Hsu, L. T.; Salvato, M.; Wuyts, S.; Galametz, A.; Lee, B.; Lee, S.-K.; Pforr, J.; Wiklind, T.; Almaini, O.; Cooper, M. C.; Weiner, B.; and others

    2015-03-10

    We present the public release of the stellar mass catalogs for the GOODS-S and UDS fields obtained using some of the deepest near-IR images available, achieved as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey project. We combine the effort from 10 different teams, who computed the stellar masses using the same photometry and the same redshifts. Each team adopted their preferred fitting code, assumptions, priors, and parameter grid. The combination of results using the same underlying stellar isochrones reduces the systematics associated with the fitting code and other choices. Thanks to the availability of different estimates, we can test the effect of some specific parameters and assumptions on the stellar mass estimate. The choice of the stellar isochrone library turns out to have the largest effect on the galaxy stellar mass estimates, resulting in the largest distributions around the median value (with a semi interquartile range larger than 0.1 dex). On the other hand, for most galaxies, the stellar mass estimates are relatively insensitive to the different parameterizations of the star formation history. The inclusion of nebular emission in the model spectra does not have a significant impact for the majority of galaxies (less than a factor of 2 for ∼80% of the sample). Nevertheless, the stellar mass for the subsample of young galaxies (age <100 Myr), especially in particular redshift ranges (e.g., 2.2 < z < 2.4, 3.2 < z < 3.6, and 5.5 < z < 6.5), can be seriously overestimated (by up to a factor of 10 for <20 Myr sources) if nebular contribution is ignored.

  3. Properties of submillimeter galaxies in the CANDELS-S goods-south field

    SciTech Connect

    Wiklind, Tommy; Dahlen, Tomas; Ferguson, Henry C.; Grogin, Norman A.; Koekemoer, Anton M.; Dickinson, Mark E.; Guo, Yicheng; Barro, Guillermo; Fontana, Adriano; Castellano, Marco; Davé, Romeel; Yan, Haojing; Acquaviva, Viviana; Ashby, Matthew L. N.; Caputi, Karina I.; Dekel, Avishai; Donley, Jennifer L.; and others

    2014-04-20

    We derive physical properties of 10 submillimeter galaxies located in the CANDELS coverage of the GOODS-S field. The galaxies were first identified as submillimeter sources with the LABOCA bolometer and subsequently targeted for 870 μm continuum observation with ALMA. The high angular resolution of the ALMA imaging allows secure counterparts to be identified in the CANDELS multiband data set. The CANDELS data provide deep photometric data from UV through near-infrared wavelengths. Using synthetic spectral energy distributions, we derive photometric redshifts, stellar masses, extinction, ages, and the star formation history. The redshift range is z = 1.65-4.76, with two of the galaxies located at z > 4. Two submillimeter galaxy (SMG) counterparts have stellar masses 2-3 orders of magnitude lower than the rest. The remaining SMG counterparts have stellar masses around 1 × 10{sup 11} M {sub ☉}. The stellar population in the SMGs is typically older than the expected duration of the submillimeter phase, suggesting that the star formation history of SMGs is more complex than a single burst. Non-parametric morphology indices suggest that the SMG counterparts are among the most asymmetric systems compared with galaxies of the same stellar mass and redshift. The Hubble Space Telescope images show that three of the SMGs are associated with ongoing mergers. The remaining counterparts are isolated. Estimating the dust and molecular gas mass from the submillimeter fluxes, and comparing with our stellar masses shows that the gas mass fraction of SMGs is ∼28% and that the final stellar mass is likely to be ∼(1-2) × 10{sup 11} M {sub ☉}.

  4. CANDELS Multi-wavelength Catalogs: Source Detection and Photometry in the GOODS-South Field

    NASA Astrophysics Data System (ADS)

    Guo, Yicheng; Ferguson, Henry C.; Giavalisco, Mauro; Barro, Guillermo; Willner, S. P.; Ashby, Matthew L. N.; Dahlen, Tomas; Donley, Jennifer L.; Faber, Sandra M.; Fontana, Adriano; Galametz, Audrey; Grazian, Andrea; Huang, Kuang-Han; Kocevski, Dale D.; Koekemoer, Anton M.; Koo, David C.; McGrath, Elizabeth J.; Peth, Michael; Salvato, Mara; Wuyts, Stijn; Castellano, Marco; Cooray, Asantha R.; Dickinson, Mark E.; Dunlop, James S.; Fazio, G. G.; Gardner, Jonathan P.; Gawiser, Eric; Grogin, Norman A.; Hathi, Nimish P.; Hsu, Li-Ting; Lee, Kyoung-Soo; Lucas, Ray A.; Mobasher, Bahram; Nandra, Kirpal; Newman, Jeffery A.; van der Wel, Arjen

    2013-08-01

    We present a UV to mid-infrared multi-wavelength catalog in the CANDELS/GOODS-S field, combining the newly obtained CANDELS HST/WFC3 F105W, F125W, and F160W data with existing public data. The catalog is based on source detection in the WFC3 F160W band. The F160W mosaic includes the data from CANDELS deep and wide observations as well as previous ERS and HUDF09 programs. The mosaic reaches a 5σ limiting depth (within an aperture of radius 0.''17) of 27.4, 28.2, and 29.7 AB for CANDELS wide, deep, and HUDF regions, respectively. The catalog contains 34,930 sources with the representative 50% completeness reaching 25.9, 26.6, and 28.1 AB in the F160W band for the three regions. In addition to WFC3 bands, the catalog also includes data from UV (U band from both CTIO/MOSAIC and VLT/VIMOS), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), and infrared (HST/WFC3 F098M, VLT/ISAAC Ks, VLT/HAWK-I Ks, and Spitzer/IRAC 3.6, 4.5, 5.8, 8.0 μm) observations. The catalog is validated via stellar colors, comparison with other published catalogs, zero-point offsets determined from the best-fit templates of the spectral energy distribution of spectroscopically observed objects, and the accuracy of photometric redshifts. The catalog is able to detect unreddened star-forming (passive) galaxies with stellar mass of 1010 M ⊙ at a 50% completeness level to z ~ 3.4 (2.8), 4.6 (3.2), and 7.0 (4.2) in the three regions. As an example of application, the catalog is used to select both star-forming and passive galaxies at z ~ 2-4 via the Balmer break. It is also used to study the color-magnitude diagram of galaxies at 0 < z < 4.

  5. CANDELS MULTI-WAVELENGTH CATALOGS: SOURCE DETECTION AND PHOTOMETRY IN THE GOODS-SOUTH FIELD

    SciTech Connect

    Guo Yicheng; Barro, Guillermo; Faber, Sandra M.; Koo, David C.; Giavalisco, Mauro; Willner, S. P.; Ashby, Matthew L. N.; Donley, Jennifer L.; Fontana, Adriano; Galametz, Audrey; Grazian, Andrea; Kocevski, Dale D.; McGrath, Elizabeth J.; Peth, Michael; Salvato, Mara; Wuyts, Stijn; and others

    2013-08-15

    We present a UV to mid-infrared multi-wavelength catalog in the CANDELS/GOODS-S field, combining the newly obtained CANDELS HST/WFC3 F105W, F125W, and F160W data with existing public data. The catalog is based on source detection in the WFC3 F160W band. The F160W mosaic includes the data from CANDELS deep and wide observations as well as previous ERS and HUDF09 programs. The mosaic reaches a 5{sigma} limiting depth (within an aperture of radius 0.''17) of 27.4, 28.2, and 29.7 AB for CANDELS wide, deep, and HUDF regions, respectively. The catalog contains 34,930 sources with the representative 50% completeness reaching 25.9, 26.6, and 28.1 AB in the F160W band for the three regions. In addition to WFC3 bands, the catalog also includes data from UV (U band from both CTIO/MOSAIC and VLT/VIMOS), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), and infrared (HST/WFC3 F098M, VLT/ISAAC Ks, VLT/HAWK-I Ks, and Spitzer/IRAC 3.6, 4.5, 5.8, 8.0 {mu}m) observations. The catalog is validated via stellar colors, comparison with other published catalogs, zero-point offsets determined from the best-fit templates of the spectral energy distribution of spectroscopically observed objects, and the accuracy of photometric redshifts. The catalog is able to detect unreddened star-forming (passive) galaxies with stellar mass of 10{sup 10} M{sub Sun} at a 50% completeness level to z {approx} 3.4 (2.8), 4.6 (3.2), and 7.0 (4.2) in the three regions. As an example of application, the catalog is used to select both star-forming and passive galaxies at z {approx} 2-4 via the Balmer break. It is also used to study the color-magnitude diagram of galaxies at 0 < z < 4.

  6. The VIMOS VLT Deep Survey. Public release of 1599 redshifts to IAB≤24 across the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Vettolani, G.; Paltani, S.; Tresse, L.; Zamorani, G.; Le Brun, V.; Moreau, C.; Bottini, D.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Garilli, B.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Mancini, D.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Arnaboldi, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Ciliegi, P.; Gregorini, L.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2004-12-01

    This paper presents the VIMOS VLT Deep Survey around the Chandra Deep Field South (CDFS). We have measured 1599 new redshifts with VIMOS on the European Observatory Very Large Telescope - UT3, in an area 21 × 21.6 arcmin2, including 784 redshifts in the Hubble Space Telescope - Advanced Camera for Surveys GOODS area. 30% of all objects with IAB=24 have been observed independently of magnitude, indicating that the sample is purely magnitude limited. We have reached an unprecedented completeness level of 84% in terms of the ratio of secure measurements vs. observed objects, while 95% of all objects have a redshift measurement. A total of 1452 galaxies, 139 stars, 8 QSOs have a redshift identification, 141 of these being unsecure measurements. The redshift distribution down to IAB=24 is peaked at a median redshift z=0.73, with a significant high redshift tail extending up to ˜4. Several high density peaks in the distribution of galaxies are identified. In particular, the strong peak at z=0.735 contains more than 130 galaxies in a velocity range ±2000 km s-1 distributed all across the transverse ˜20 h-1 Mpc of the survey. We are releasing all redshifts to the community, along with the cross identification with HST-ACS GOODS sources on the CENCOS database environment http://cencosw.oamp.fr. The data presented in this paper has been obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile.

  7. Oily-waste-disposal survey, South Tank Farm, Lajes Field, Azores. Final report, 12-17 Jun 90

    SciTech Connect

    Binovi, R.D.

    1991-03-01

    A survey of the wet and dry sludge pits at the South Tank Farm, Lajes Field, Azores was performed by members of the AFOEHL. Samples of the waste water and sludge from the wet sludge pit (WSP) were taken as well as from the dry sludge pit. Bioremediation studies, incineration, and carbon adsorption studies were performed. The characterization of the waste water from the WSP revealed a one phase mixture of mostly soluble oils and grease with an average COD concentration of 1760 and a BOD of 407 mg/1. Oils and grease concentrations were in the 10 mg/1 range. The characterization of the sludge revealed 43% organics and concentrations of metals not high enough for consideration as hazardous waste. The sludge from the DSP also did not have levels of metals high enough for special disposal as hazardous waste. The WSP waste water was slow to degrade biologically through stimulation of indigenous organisms. Carbon was effective in removing COD. The WSP waste water has subsequently been released to the Praia Bay and the sludge recovered and drummed. Recommendations included the construction of a secondary sewage treatment plant to service the base, airport, and Praia, the construction of a sludge drying facility and testing of the dried sludge for ultimate disposal.

  8. VHF coherent scatter radar observations of mid-latitude F-region field-aligned irregularities over South Korea

    NASA Astrophysics Data System (ADS)

    Kwak, Y.; Yang, T.; Lee, J.; Hwang, J.; Kil, H.; Park, Y.

    2011-12-01

    We examine the mid-latitude F-region field-aligned irregularity (FAI) activity during 2010-2011 by using the VHF coherent scatter radar data in Daejeon (36.2°N, 127.1°E; dip latitude 26.7°N), South Korea. The VHF radar has been operated since December 2009 and provides a unique opportunity to investigate the variability of the FAI activity with local time, season, solar flux, and magnetic activity. Our preliminary results during the solar minimum show that FAIs preferentially occur at post-sunset and pre-sunrise and during the June solstice. The seasonal variation of the FAI occurrence frequency is similar to that of the electron density irregularities observed by the C/NOFS satellite. For one event, we observed the association of the FAIs with a medium-scale traveling ionospheric disturbance (MSTID). Our study extends to the investigation of the correlations between the irregularities in the equatorial region and middle latitudes and between the conjugate F regions, and the causal linkage of the FAIs with the E-region perturbations. For this purpose, we analyze the VHF radar and C/NOFS data during 2010-2011.

  9. THE VERY LARGE ARRAY 1.4 GHz SURVEY OF THE EXTENDED CHANDRA DEEP FIELD SOUTH: SECOND DATA RELEASE

    SciTech Connect

    Miller, Neal A.; Bonzini, Margherita; Mainieri, Vincenzo; Padovani, Paolo; Rosati, Piero; Fomalont, Edward B.; Kellermann, Kenneth I.; Tozzi, Paolo; Vattakunnel, Shaji

    2013-04-01

    Deep radio observations at 1.4 GHz for the Extended Chandra Deep Field South were performed in 2007 June through September and presented in a first data release. The survey was made using six separate pointings of the Very Large Array with over 40 hr of observation per pointing. In the current paper, we improve on the data reduction to produce a second data release (DR2) mosaic image. This DR2 image covers an area of about a third of a square degree, reaches a best rms sensitivity of 6 {mu}Jy, and has a typical sensitivity of 7.4 {mu}Jy per 2.''8 by 1.''6 beam. We also present a more comprehensive catalog, including sources down to peak flux densities of five or more times the local rms noise along with information on source sizes and relevant pointing data. We discuss in some detail the consideration of whether sources are resolved under the complication of a radio image created as a mosaic of separate pointings each suffering some degree of bandwidth smearing, and the accurate evaluation of the flux densities of such sources. Finally, the radio morphologies and optical/near-IR counterpart identifications are used to identify 17 likely multiple-component sources and arrive at a catalog of 883 radio sources, which is roughly double the number of sources contained in the first data release.

  10. An Integrated Study of the Grayburg/San Andres Reservoir, Foster and South Cowden Fields, Ector County Texas

    SciTech Connect

    Weinbrandt, Richard; Trentham, Robert C; Robinson, William

    1997-10-23

    For a part of the Foster and South Cowden (Grayburg-San Andres) oil fields, improvement in oil production has been accomplished, in part, by using "pipeline fracturing" technology in the most recent completion to improve fluid flow rates, and filtration of waterflood injection water to preserve reservoir permeability. The 3D seismic survey acquired in conjunction with this DOE project has been used to calculate a 3D seismic inversion model, which has been analyzed to provide detailed maps of porosity within the productive upper 250 feet of the Grayburg Formation. Geologic data, particularly from logs and cores, have been combined with the geophysical interpretation and production history information to develop a model of the reservoir that defines estimations of remaining producible oil. The integrated result is greater than the sum of its parts, since no single data form adequately describes the reservoir. Each discipline relies upon computer software that runs on PC-type computers, allowing virtually any size company to affordably access the technology required to achieve similar results.

  11. Influence of deflection on a fold-to-fault progression: field evidence from near Marietta, South Carolina

    USGS Publications Warehouse

    Clendenin, C.W.; Garihan, J.M.

    2006-01-01

    Four periods of deformation (D1-D4) are recognized in the Lion Park Road borrow pit near Marietta, South Carolina. Although each period is characterized by distinct structures, D3 produced two structural styles (D3a, D3b) resulting from layer-parallel shortening. D3a is characterized by detachment folding at the tip of an underlying thrust. D3b is a fold-to-fault progression that was localized by east-dipping, quartz-filled gash fractures. The fold-to-fault progression demonstrates the influence of a mechanical anisotropy on ramp development. The early stages of D3b were formed by deflection of northwest-directed, layer-parallel shortening and active, down-section propagation of folds and thrusts. Following connection with a splay of basal detachment, later D3b stages resulted from up-section movement that produced kink folding and a throughgoing thrust. This up-section movement deformed and modified the geometries of older, down-section structures. Detailed mesoscopic field observations, integrated with a combination of current thrust fault models, are used to interpret the D3b fold-to-fault progression. ?? 2006 Elsevier Ltd. All rights reserved.

  12. Co-transmission of the non-transmissible South African Babesia bovis S24 vaccine strain during mixed infection with a field isolate.

    PubMed

    Combrink, M P; Troskie, P C; de Klerk, D G; Pienaar, R; Latif, A A; Mans, B J

    2015-03-01

    The South African Babesia bovis live blood vaccine, originating from a field isolate attenuated by 23 serial syringe passages in splenectomized calves, has lost the ability to infect the natural vector Rhipicephalus (Boophilus) microplus. In this study, infection with mixed parasites from the vaccine strain and a field isolate, resulted in transmission of both genotype populations. Comparing the field isolate and transmitted combination indicated no significant difference in their virulence, while challenge of vaccinated cattle with these isolates showed the ability of the vaccine to protect against both. Limiting dilution of the transmitted combination, followed by infection of splenectomized cattle (n=34) yielded no single infections for the vaccine strain genotype, seven clonal lines of the field isolate and one mixture of vaccine strain and field isolate. Only one of two field isolate clonal lines selected for vector transmission study was transmitted. Showing that B. bovis isolates can contain both tick transmissible and non-transmissible subpopulations. The findings of this study also indicate the probability of vaccine co-infection transmission occurring in the field, which may result in new genotype populations of B. bovis. However, the impact of this recombination with field isolates is considered negligible since a genotypically diverse population of B. bovis is already present in South Africa.

  13. Bent-tailed radio sources in the australia telescope large area survey of the Chandra deep field south

    SciTech Connect

    Dehghan, S.; Johnston-Hollitt, M.; Franzen, T. M. O.; Norris, R. P.; Miller, N. A.

    2014-11-01

    Using the 1.4 GHz Australia Telescope Large Area Survey, supplemented by the 1.4 GHz Very Large Array images, we undertook a search for bent-tailed (BT) radio galaxies in the Chandra Deep Field South. Here we present a catalog of 56 detections, which include 45 BT sources, 4 diffuse low-surface-brightness objects (1 relic, 2 halos, and 1 unclassified object), and a further 7 complex, multi-component sources. We report BT sources with rest-frame powers in the range 10{sup 22} ≤ P {sub 1.4} {sub GHz} ≤ 10{sup 26} W Hz{sup –1}, with redshifts up to 2 and linear extents from tens of kiloparsecs up to about 1 Mpc. This is the first systematic study of such sources down to such low powers and high redshifts and demonstrates the complementary nature of searches in deep, limited area surveys as compared to shallower, large surveys. Of the sources presented here, one is the most distant BT source yet detected at a redshift of 2.1688. Two of the sources are found to be associated with known clusters: a wide-angle tail source in A3141 and a putative radio relic which appears at the infall region between the galaxy group MZ 00108 and the galaxy cluster AMPCC 40. Further observations are required to confirm the relic detection, which, if successful, would demonstrate this to be the least powerful relic yet seen with P {sub 1.4} {sub GHz} = 9 × 10{sup 22} W Hz{sup –1}. Using these data, we predict future 1.4 GHz all-sky surveys with a resolution of ∼10 arcsec and a sensitivity of 10 μJy will detect of the order of 560,000 extended low-surface-brightness radio sources of which 440,000 will have a BT morphology.

  14. Quantification and regionalization of groundwater recharge in South-Central Kansas: Integrating field characterization, statistical analysis, and GIS

    USGS Publications Warehouse

    Sophocleous, M.

    2000-01-01

    A practical methodology for recharge characterization was developed based on several years of field-oriented research at 10 sites in the Great Bend Prairie of south-central Kansas. This methodology combines the soil-water budget on a storm-by-storm year-round basis with the resulting watertable rises. The estimated 1985-1992 average annual recharge was less than 50mm/year with a range from 15 mm/year (during the 1998 drought) to 178 mm/year (during the 1993 flood year). Most of this recharge occurs during the spring months. To regionalize these site-specific estimates, an additional methodology based on multiple (forward) regression analysis combined with classification and GIS overlay analyses was developed and implemented. The multiple regression analysis showed that the most influential variables were, in order of decreasing importance, total annual precipitation, average maximum springtime soil-profile water storage, average shallowest springtime depth to watertable, and average springtime precipitation rate. Therefore, four GIS (ARC/INFO) data "layers" or coverages were constructed for the study region based on these four variables, and each such coverage was classified into the same number of data classes to avoid biasing the results. The normalized regression coefficients were employed to weigh the class rankings of each recharge-affecting variable. This approach resulted in recharge zonations that agreed well with the site recharge estimates. During the "Great Flood of 1993," when rainfall totals exceeded normal levels by -200% in the northern portion of the study region, the developed regionalization methodology was tested against such extreme conditions, and proved to be both practical, based on readily available or easily measurable data, and robust. It was concluded that the combination of multiple regression and GIS overlay analyses is a powerful and practical approach to regionalizing small samples of recharge estimates.

  15. Variability Selected Low-Luminosity Active Galactic Nuclei in the 4 Ms Chandra Deep Field-South

    NASA Technical Reports Server (NTRS)

    Young, M.; Brandt, W. N.; Xue, Y. Q.; Paolillo, D. M.; Alexander, F. E.; Bauer, F. E.; Lehmer, B. D.; Luo, B.; Shemmer, O.; Schneider, D. P.; Vignail, C.

    2012-01-01

    The 4 Ms Chandra Deep Field-South (CDF-S) and other deep X-ray surveys have been highly effective at selecting active galactic nuclei (AGN). However, cosmologically distant low-luminosity AGN (LLAGN) have remained a challenge to identify due to significant contribution from the host galaxy. We identify long-term X ray variability (approx. month years, observed frame) in 20 of 92 CDF-S galaxies spanning redshifts approx equals 00.8 - 1.02 that do not meet other AGN selection criteria. We show that the observed variability cannot be explained by X-ray binary populations or ultraluminous X-ray sources, so the variability is most likely caused by accretion onto a supermassive black hole. The variable galaxies are not heavily obscured in general, with a stacked effective power-law photon index of Gamma(sub Stack) approx equals 1.93 +/- 0.13, and arc therefore likely LLAGN. The LLAGN tend to lie it factor of approx equal 6-89 below the extrapolated linear variability-luminosity relation measured for luminous AGN. This may he explained by their lower accretion rates. Variability-independent black-hole mass and accretion-rate estimates for variable galaxies show that they sample a significantly different black hole mass-accretion-rate space, with masses a factor of 2.4 lower and accretion rates a factor of 22.5 lower than variable luminous AGNs at the same redshift. We find that an empirical model based on a universal broken power-law power spectral density function, where the break frequency depends on SMBH mass and accretion rate, roughly reproduces the shape, but not the normalization, of the variability-luminosity trends measured for variable galaxies and more luminous AGNs.

  16. UV-DROPOUT GALAXIES IN THE GOODS-SOUTH FIELD FROM WFC3 EARLY RELEASE SCIENCE OBSERVATIONS

    SciTech Connect

    Hathi, N. P.; Ryan, R. E.; Cohen, S. H.; Windhorst, R. A.; Rutkowski, M. J.; Yan, H.; McCarthy, P. J.; O'Connell, R. W.; Koekemoer, A. M.; Bond, H. E.; Balick, B.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; Kimble, R. A.; Paresce, F.; Saha, A.

    2010-09-10

    We combine new high sensitivity ultraviolet (UV) imaging from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) with existing deep HST/Advanced Camera for Surveys optical images from the Great Observatories Origins Deep Survey (GOODS) program to identify UV-dropouts, which are Lyman break galaxy (LBG) candidates at z {approx_equal} 1-3. These new HST/WFC3 observations were taken over 50 arcmin{sup 2} in the GOODS-South field as a part of the Early Release Science program. The uniqueness of these new UV data is that they are observed in three UV/optical (WFC3 UVIS) channel filters (F225W, F275W, and F336W), which allows us to identify three different sets of UV-dropout samples. We apply Lyman break dropout selection criteria to identify F225W-, F275W-, and F336W-dropouts, which are z {approx_equal} 1.7, 2.1, and 2.7 LBG candidates, respectively. We use multi-wavelength imaging combined with available spectroscopic and photometric redshifts to carefully access the validity of our UV-dropout candidates. Our results are as follows: (1) these WFC3 UVIS filters are very reliable in selecting LBGs with z {approx_equal} 2.0, which helps to reduce the gap between the well-studied z {approx}> 3 and z {approx} 0 regimes; (2) the combined number counts with average redshift z {approx_equal} 2.2 agree very well with the observed change in the surface densities as a function of redshift when compared with the higher redshift LBG samples; and (3) the best-fit Schechter function parameters from the rest-frame UV luminosity functions at three different redshifts fit very well with the evolutionary trend of the characteristic absolute magnitude, M*, and the faint-end slope, {alpha}, as a function of redshift. This is the first study to illustrate the usefulness of the WFC3 UVIS channel observations to select z {approx}< 3 LBGs. The addition of the new WFC3 on the HST has made it possible to uniformly select LBGs from z {approx_equal} 1 to z {approx_equal} 9 and

  17. AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: NEAR-INFRARED MORPHOLOGIES AND STELLAR SIZES

    SciTech Connect

    Chen, Chian-Chou; Smail, Ian; Swinbank, A. M.; Simpson, J. M.; Ma, Cheng-Jiun; Alexander, D. M.; Danielson, A. L. R.; Edge, A. C.; Biggs, A. D.; Ivison, R. J.; Brandt, W. N.; Chapman, S. C.; Coppin, K. E. K.; Dannerbauer, H.; Greve, T. R.; Karim, A.; Menten, Karl M.; Schinnerer, E.; Walter, F.; Wardlow, J. L.; and others

    2015-02-01

    We analyze Hubble Space Telescope WFC3/H {sub 160}-band observations of a sample of 48 Atacama Large Millimeter/submillimeter Array detected submillimeter galaxies (SMGs) in the Extended Chandra Deep Field South field, to study their stellar morphologies and sizes. We detect 79% ± 17% of the SMGs in the H {sub 160}-band imaging with a median sensitivity of 27.8 mag, and most (80%) of the nondetections are SMGs with 870 μm fluxes of S {sub 870} < 3 mJy. With a surface brightness limit of μ {sub H} ∼ 26 mag arcsec{sup –2}, we find that 82% ± 9% of the H {sub 160}-band-detected SMGs at z = 1-3 appear to have disturbed morphologies, meaning they are visually classified as either irregulars or interacting systems, or both. By determining a Sérsic fit to the H {sub 160} surface brightness profiles, we derive a median Sérsic index of n = 1.2 ± 0.3 and a median half-light radius of r{sub e} = 4.4{sub −0.5}{sup +1.1} kpc for our SMGs at z = 1-3. We also find significant displacements between the positions of the H {sub 160} component and 870 μm emission in these systems, suggesting that the dusty starburst regions and less-obscured stellar distribution are not colocated. We find significant differences in the sizes and the Sérsic index between our z = 2-3 SMGs and z ∼ 2 quiescent galaxies, suggesting that a major transformation of the stellar light profile is needed in the quenching processes if SMGs are progenitors of the red-and-dead z ∼ 2 galaxies. Given the short-lived nature of SMGs, we postulate that the majority of the z = 2-3 SMGs with S {sub 870} ≳ 2 mJy are early/mid-stage major mergers.

  18. Climate-sensitive subsea permafrost and related gas expulsions on the South Kara Sea shelf. Field studies and modeling results.

    NASA Astrophysics Data System (ADS)

    Portnov, Alexey; Mienert, Jurgen; Serov, Pavel

    2015-04-01

    Thawing subsea permafrost controls methane release bearing a considerable impact on the climate-sensitive Arctic environment. Significant expulsion of methane into shallow Russian shelf areas may continue to rise into the atmosphere on the Arctic shelves in response to intense degradation of relict subsea permafrost. The release of formerly trapped gas, essentially methane, is linked to the permafrost evolution. Modeling of the permafrost at the West Yamal shelf allowed describing its evolution from the Late Pleistocene to Holocene. During the previous work we detected extensive emissions of free gas into the water column at the boundary between today's shallow water permafrost and deeper water non-permafrost areas. These gas expulsions formed seismic and hydro-acoustic anomalies on the high-resolution seismic records. We supposed that in the water depths <20m continuous ice-bearing permafrost plays a role of a seal through which gas can not migrate. We integrate 1D modeling results of relict permafrost distributions with these field data from the South Kara Sea. Modeling results suggest a highly-dynamic permafrost system that directly responds to even minor variations of lower and upper boundary conditions, e.g. heat flux from below and/or bottom water temperature changes from above. We present several scenarios of permafrost evolution and show that potentially minimal modern extent of the permafrost at the West Yamal shelf is limited by ~17 m isobaths, whereas maximal probable extent coincides with ~100 m isobaths. The model also predicts seaward tapering of relict permafrost with its maximal thickness 275-390 m near the shore line. We also present sensitivity analysis which define the wider range of modeling results depending on the changing input parameters (e.g. geothermal heat flux, bottom water temperature, porosity of the sediments). The model adapts well to corresponding field data, providing crucial information about the modern permafrost conditions

  19. Paleosecular variations of geomagnetic field from the Last Glacial Maximum to the Holocene in the north of South China Sea

    NASA Astrophysics Data System (ADS)

    Yang, X.; Huang, W.; Liu, Q.

    2012-12-01

    The high-resolution geomagnetic field records from the Last Glacial Maximum to the Holocene, which possessed of a notable climate change, were scarce in the global area. In this abstract, two gravity piston cores ZSQD2 (114.16oE, 19.58oN, ~190 cm in length, water depth 681m) and ZSQD34 (114.74oE, 19.05oN, ~184 cm in length, water depth 1820 m), situated in the north of South China Sea, were selected to study the secular variations of geomagnetic field in this area. Radiocarbon ages of G.sacculifer suggest that the deposition rate varied with 56.1 cm/kyr and 3.7 cm/kyr during the Last Glacial and the Holocene, respectively. Rock magnetic results indicate that the pseudo-single domain magnetite with low coercivity dominate the properties of sediments. The characteristic remanent magnetization (ChRM) values are evaluated using the 5-8 AF steps when MAD values are generally <5. Constrained by the radiocarbon chronology, the secular variation curves since ~18 cal. kyr can be constructed using the ChRM directions and NRM/ARM ratios (as a proxy of relative intensity). Comparing the Holocene SV with that from terrestrial lakes in Southern China, similar shape corroborates the reliability of records and uniform pattern of non-dipole magnetic field. Two significant features on SV curves present the geomagnetic field characteristics from ~17 cal. kyr to the early Holocene. One is that the direction variations lag behind the relative intensity on the millennium time scale. Such as a major direction shift occurred around 13 cal. kyr while the relative intensity low was about 14 cal. kyr. Another feature is the fast and frequent wiggles both in direction and intensity between ~17 to ~14.5 cal. kyr. During this period, two significant negative inclination anomalies occurred at ~16.4 and ~15.4 cal. kyr associated with low intensity, respectively. Nevertheless, the corresponding declinations did not show the reversed features although they had also some slight fluctuations. The

  20. Microanalysis of the aerosol collected over south-central New Mexico during the alive field experiment, May-December 1989

    NASA Astrophysics Data System (ADS)

    Sheridan, Patrick J.; Schnell, Russel C.; Kahl, Jonathan D.; Boatman, Joe F.; Garvey, Dennis M.

    Thirty-eight size-segregated aerosol samples were collected in the lower troposphere over the high desert of south-central New Mexico, using cascade impactors mounted onboard two research aircraft. Four of these samples were collected in early May, sixteen in mid-July, and the remaining ones in December 1989, during three segments of the ALIVE field initiative. Analytical electron microscope analyses of aerosol deposits and individual particles from these samples were performed to physically and chemically characterize the major particulate species present in the aerosol. Air-mass trajectories arriving at the sampling area in the May program were quite different from those calculated for the July period. In general, the May trajectories showed strong westerly winds, while the July winds were weaker and southerly, consistently passing over or very near the border cities of El Paso, Texas, and Ciudad Juarez, Mexico. Aerosol samples collected during the May period were predominantly fine (0.1-0.5 μm dia.), liquid H 2SO 4 droplets. Samples from the July experiment were comprised mostly of fine, solid (NH 4) 2SO 4 or mostly neutralized sulfate particles. In both sampling periods, numerous other particle classes were observed, including many types with probable terrestrial or anthropogenic sources. The numbers of these particles, however, were small when compared with the sulfates. Composite particle types, including sulfate/crustal and sulfate/carbonaceous, were also found to be present. The major differences in aerosol composition between the May and July samples (i.e. the extensive neutralization of sulfates in the July samples) can be explained by considering the different aerosol transport pathways and the proximity of the July aerosol to the El Paso/Juarez urban plume. Winds during the December experiment were quite variable, and may have contributed to the widely varying aerosol compositions observed in these samples. When the aircraft sampled the El Paso

  1. The rogue wave of 27 August 1969 at Dwarskersbos, South Africa: Field survey and simulation as a meteo-tsunami

    NASA Astrophysics Data System (ADS)

    Okal, Emile; de Beer, Coenie; Visser, Johan; Kalligeris, Nikos

    2013-04-01

    In the early hours of Wednesday, 27 August 1969, the village of Dwarskersbos, Western Cape, South Africa, was inundated by a wave which flooded houses and damaged small boats. This small tsunami took place in the absence of any seismic source or extreme weather, and its origin has remained mysterious. In September 2010, we conducted a field survey based on the interview of nine elderly witnesses still living in the village, using techniques developed earlier for the study of the 1946 Aleutian and 1956 Greek tsunamis. We measured 13 locations, with run-up reaching 2.9 m for a maximum inundation of 260 m from the sea shore. The most remarkable aspect of our dataset is the extreme concentration of the flooding along a stretch of coastline of less than 2 km. In particular, the tsunami did not reach the communities located on the opposite side of St. Helena's Bay, nor did it affect Elands Bay and Lamberts Bay, respectively 43 and 68 km to the North. In order to investigate the possible origin of the Dwarskersbos tsunami, we first simulated an underwater landslide taking place in a canyon 20 km Northwest of Shelley Point, using the MOST code. This model predicts comparable amplitudes along most of the regional coastlines, and thus fails to explain the documented concentration at Dwarskersbos. By contrast, we explore a meteorological origin for the event by simulating the coupling between a possible squall (modeled as a steep pressure front) propagating over St. Helena's Bay and the oceanic column, using Proudman's [1953] original model, as applied by Platzman [1958] to the case of the 1954 Chicago rogue wave. We find that a front moving at 15 m/s in the azimuth N100E can resonate exclusively with the shallow bathymetry off Dwarskersbos, and thus explain most of the features revealed by our survey. This interpretation would be in contrast to the case of the tsunami of 21 August 2008, for which a comprehensive seriesof maregraphs along a 900-km stretch of coastline

  2. Horizontal and vertical deformation field in New Caledonia, South West Pacific, derived from more than 20 years of GNSS measurements

    NASA Astrophysics Data System (ADS)

    Ballu, V.; Calmant, S.; Valty, P.; Gravelle, M.; Sakic, P.; Aucan, J.; Pelletier, B.

    2015-12-01

    New Caledonia is located in the South West Pacific Ocean, on the Australian Plate just before its subduction under the North Fiji Basin. Because it is on the subducting side of the plate interface, New Caledonia is considered to be stable to first order and not to undergo rapid deformation. However, moderate seismicity is recorded close to the plate interface, in the southern part of the main land and along the Loyalty ridge. In addition, the main island and Loyalty ridge are subjected to long-term vertical deformation due to the flexure of the plate entering subduction. A geodetic network was installed since the early days of GPS (~1990) and has been further developed and occasionally measured since. Due to the low number of global GNSS recording stations in the early 1990s, the positioning accuracy that can be achieved with these data is poor compared to present-day standards, and expected movements are slow (possibly less than 1 mm/yr). However, the >20 year length of the time series may allow us to determine the current deformation field in New Caledonia and Loyalty Ridge. We pay special care in using older GNSS data for characterizing ground motions, reprocessing all available data using a range of different processing strategies and products. We calculated daily positions from double-differenced ionosphere-free carrier phase data in a global network using the GAMIT software and combined and aligned the results on the ITRF2008 using the CATREF software, according to the processing strategy developed as part of the current ULR6 (www.sonel.org) reprocessing campaign for IGS. We compare the double difference results with those obtained in PPP mode using JPL GIPSY software as well as CNES GINS software and different products (MIT, JPL and GRG orbits and clocks provided in the framework of the IGS2 reprocessing campaign). We present both the results for New Caledonia and an analysis of the applicability of these different processing strategies to older GNSS

  3. The ATLAS 5.5 GHz survey of the extended Chandra Deep Field South: the second data release

    NASA Astrophysics Data System (ADS)

    Huynh, M. T.; Bell, M. E.; Hopkins, A. M.; Norris, R. P.; Seymour, N.

    2015-11-01

    We present a new image of the 5.5 GHz radio emission from the extended Chandra Deep Field South. Deep radio observations at 5.5 GHz were obtained in 2010 and presented in the first data release. A further 76 h of integration has since been obtained, nearly doubling the integration time. This paper presents a new analysis of all the data. The new image reaches 8.6 μJy rms, an improvement of about 40 per cent in sensitivity. We present a new catalogue of 5.5 GHz sources, identifying 212 source components, roughly 50 per cent more than were detected in the first data release. Source counts derived from this sample are consistent with those reported in the literature for S5.5 GHz > 0.1 mJy but significantly lower than published values in the lowest flux density bins (S5.5 GHz < 0.1 mJy), where we have more detected sources and improved statistical reliability. The 5.5 GHz radio sources were matched to 1.4 GHz sources in the literature and we find a mean spectral index of -0.35 ± 0.10 for S5.5 GHz > 0.5 mJy, consistent with the flattening of the spectral index observed in 5 GHz sub-mJy samples. The median spectral index of the whole sample is αmed = -0.58, indicating that these observations may be starting to probe the star-forming population. However, even at the faintest levels (0.05 < S5.5 GHz < 0.1 mJy), 39 per cent of the 5.5 GHz sources have flat or inverted radio spectra. Four flux density measurements from our data, across the full 4.5-6.5 GHz bandwidth, are combined with those from literature and we find 10 per cent of sources (S5.5 GHz ≳ 0.1 mJy) show significant curvature in their radio spectral energy distribution spanning 1.4-9 GHz.

  4. EMISSION-LINE GALAXIES FROM THE HUBBLE SPACE TELESCOPE PROBING EVOLUTION AND REIONIZATION SPECTROSCOPICALLY (PEARS) GRISM SURVEY. I. THE SOUTH FIELDS

    SciTech Connect

    Straughn, Amber N.; Gardner, Jonathan P.; Pirzkal, Norbert; Grogin, Norman; Panagia, Nino; Meurer, Gerhardt R.; Cohen, Seth H.; Windhorst, Rogier A.; Malhotra, Sangeeta; Rhoads, James; Jansen, Rolf A.; Hathi, Nimish P.; Di Serego Alighieri, Sperello; Gronwall, Caryl; Walsh, Jeremy; Pasquali, Anna; Xu, Chun

    2009-10-15

    We present results of a search for emission-line galaxies (ELGs) in the southern fields of the Hubble Space Telescope Probing Evolution And Reionization Spectroscopically (PEARS) grism survey. The PEARS South Fields consist of five Advanced Camera for Surveys pointings (including the Hubble Ultra Deep Field) with the G800L grism for a total of 120 orbits, revealing thousands of faint object spectra in the GOODS-South region of the sky. ELGs are one subset of objects that are prevalent among the grism spectra. Using a two-dimensional detection and extraction procedure, we find 320 emission lines originating from 226 galaxy 'knots' within 192 individual galaxies. Line identification results in 118 new grism-spectroscopic redshifts for galaxies in the GOODS-South Field. We measure emission-line fluxes using standard Gaussian fitting techniques. At the resolution of the grism data, the H{beta} and [O III] doublet are blended. However, by fitting two Gaussian components to the H{beta} and [O III] features, we find that many of the PEARS ELGs have high [O III]/H{beta} ratios compared to other galaxy samples of comparable luminosities. The star formation rates of the ELGs are presented, as well as a sample of distinct giant star-forming regions at z {approx} 0.1-0.5 across individual galaxies. We find that the radial distances of these H II regions in general reside near the galaxies' optical continuum half-light radii, similar to those of giant H II regions in local galaxies.

  5. A coordinated study of a storm system over the South American continent. 1. Weather information and quasi-DC stratospheric electric field data

    NASA Astrophysics Data System (ADS)

    Pinto, O.; Pinto, I. R. C. A.; Gin, R. B. B.; Mendes, O.

    1992-11-01

    This paper reports on a coordinated campaign conducted in Brazil, December 13, 1989, to study the electrical signatures associated with a large storm system over the South American continent. Inside the storm, large convective cells developed extending up to the tropopause, as revealed from meteorological balloon soundings. Quasi-DC vertical electric field and temperature were measured by zero-pressure balloon-borne payload launched from Cachoeira Paulista, Brazil. The data were supported by radar and GOES satellite observations, as well as by a lightning position and tracking system (LPATS). The analysis of infrared imagery supports the general tendency for lightning strikes to be near to but not exactly under the coldest cloud tops. In turn, the radar maps located the strikes near to but outside of the most intense areas of precipitation (reflectivity levels above 40 dBz). The balloon altitude and stratospheric temperature show significant variations in association with the storm. The quasi-DC vertical electric field remained almost during the whole flight in a reversed direction relative to the usual fair weather downward orientation with values as large as 4 V/m. A simple calculation based on a static dipole model of electrical cloud structure gives charges of some tens of coulombs. In contrast with most electric field measurements in other regions, no indication of an intensification of the vertical field in the downward fair weather orientation was observed. This fact is in agreement with past observations in the South American region and seems to be related to a particular type of storm that would occur with more frequency in this region. If so, such a difference may have an important role in the global atmospheric electrical circuit, considering that South America is believed to give a significant current contribution to the global circuit.

  6. A compilation of field surveys on gaseous elemental mercury (GEM) from contrasting environmental settings in Europe, South America, South Africa and China: separating fads from facts.

    PubMed

    Higueras, Pablo; Oyarzun, Roberto; Kotnik, Joze; Esbrí, José María; Martínez-Coronado, Alba; Horvat, Milena; López-Berdonces, Miguel Angel; Llanos, Willians; Vaselli, Orlando; Nisi, Barbara; Mashyanov, Nikolay; Ryzov, Vladimir; Spiric, Zdravko; Panichev, Nikolay; McCrindle, Rob; Feng, Xinbin; Fu, Xuewu; Lillo, Javier; Loredo, Jorge; García, María Eugenia; Alfonso, Pura; Villegas, Karla; Palacios, Silvia; Oyarzún, Jorge; Maturana, Hugo; Contreras, Felicia; Adams, Melitón; Ribeiro-Guevara, Sergio; Niecenski, Luise Felipe; Giammanco, Salvatore; Huremović, Jasna

    2014-08-01

    Mercury is transported globally in the atmosphere mostly in gaseous elemental form (GEM, [Formula: see text]), but still few worldwide studies taking into account different and contrasted environmental settings are available in a single publication. This work presents and discusses data from Argentina, Bolivia, Bosnia and Herzegovina, Brazil, Chile, China, Croatia, Finland, Italy, Russia, South Africa, Spain, Slovenia and Venezuela. We classified the information in four groups: (1) mining districts where this contaminant poses or has posed a risk for human populations and/or ecosystems; (2) cities, where the concentration of atmospheric mercury could be higher than normal due to the burning of fossil fuels and industrial activities; (3) areas with natural emissions from volcanoes; and (4) pristine areas where no anthropogenic influence was apparent. All the surveys were performed using portable LUMEX RA-915 series atomic absorption spectrometers. The results for cities fall within a low GEM concentration range that rarely exceeds 30 ng m(-3), that is, 6.6 times lower than the restrictive ATSDR threshold (200 ng m(-3)) for chronic exposure to this pollutant. We also observed this behavior in the former mercury mining districts, where few data were above 200 ng m(-3). We noted that high concentrations of GEM are localized phenomena that fade away in short distances. However, this does not imply that they do not pose a risk for those working in close proximity to the source. This is the case of the artisanal gold miners that heat the Au-Hg amalgam to vaporize mercury. In this respect, while GEM can be truly regarded as a hazard, because of possible physical-chemical transformations into other species, it is only under these localized conditions, implying exposure to high GEM concentrations, which it becomes a direct risk for humans.

  7. Tillage and slope position impact on field-scale hydrologic processes in the South Atlantic Coastal Plain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is widespread interest in increasing conservation-tillage use during row crop production. Hydrologic monitoring was conducted for 11 years on a 1.2 ha hillslope located in the Atlantic Coastal Plain region of south central Georgia. The site was equally divided between two tillage treatments,...

  8. Higher Education Research as a Field of Study in South Korea: Inward but Starting to Look Outward

    ERIC Educational Resources Information Center

    Jung, Jisun

    2015-01-01

    This study aims to explore the development of higher education research in South Korea based on historical and scientometric perspectives. After the evolution of the country's higher education research community is presented, articles focusing on higher education from 1995 to 2012 are analysed. In total, 145 articles in international journals and…

  9. Predicting plant water content in Eucalyptus grandis forest stands in KwaZulu-Natal, South Africa using field spectra resampled to the Sumbandila Satellite Sensor

    NASA Astrophysics Data System (ADS)

    Oumar, Z.; Mutanga, O.

    2010-06-01

    The measurement of plant water content is essential to assess stress and disturbance in forest plantations. Traditional techniques to assess plant water content are costly, time consuming and spatially restrictive. Remote sensing techniques offer the alternative of a non-destructive and instantaneous method of assessing plant water content over large spatial scales where ground measurements would be impossible on a regular basis. In the context of South Africa, due to the cost and availability of imagery, studies focusing on the estimation of plant water content using remote sensing data have been limited. With the scheduled launch of the South African satellite SumbandilaSat evident in 2009, it is imperative to test the utility of this satellite in estimating plant water content. This study resamples field spectral data measured from a field spectrometer to the band settings of the SumbandilaSat in order to test its potential in estimating plant water content in a Eucalyptus plantation. The resampled SumbandilaSat wavebands were input into a neural network due to its ability to model non-linearity in a dataset and its inherent ability to perform better than conventional linear models. The integrated approach involving neural networks and the resampled field spectral data successfully predicted plant water content with a correlation coefficient of 0.74 and a root mean square error (RMSE) of 1.41% on an independent test dataset outperforming the traditional multiple regression method of estimation. The best-trained neural network algorithm that was chosen for assessing the relationship between plant water content and the SumbandilaSat bands was based on a few points only and more research is required to test the robustness and effectiveness of this sensor in estimating plant water content across different species and seasons. This is critical for monitoring plantation health in South Africa using a cheaply available local sensor containing key vegetation wavelengths.

  10. Comparing the performance of coupled soil-vegetation-atmosphere models at two contrasting field sites in South-West Germany

    NASA Astrophysics Data System (ADS)

    Gayler, S.; Wöhling, T.; Priesack, E.; Wizemann, H.-D.; Wulfmeyer, V.; Ingwersen, J.; Streck, T.

    2012-04-01

    of their structural complexity on two winter wheat research fields under different climate in South-West Germany. We investigate the ability of the models to simultaneously fit measured soil water contents, leaf area development and actual evapotranspiration rates from eddy-covariance measurements. The calibration of the models is performed in a multi-criteria context using three objective functions, which describe the discrepancy between measurements and simulations of the three data types. We use the AMALGAM evolutionary search algorithm to simultaneously estimate the most important plant and soil hydraulic parameters. The results show that the trade-off in fitting soil moisture, leaf area development and evapotranspiration can be quite large for those models that represent plant processes by simple concepts. However, these trade-offs are smaller for the more mechanistic plant growth models, so that it can be expected that these optimized mechanistic models will provide the basis for improved simulations of land-surface-atmosphere feedback processes.

  11. VizieR Online Data Catalog: LESS photometric redshift survey (Wardlow+, 2011)

    NASA Astrophysics Data System (ADS)

    Wardlow, J. L.; Smail, I.; Coppin, K. E. K.; Alexander, D. M.; Brandt, W. N.; Danielson, A. L. R.; Luo, B.; Swinbank, A. M.; Walter, F.; Weiss, A.; Xue, Y. Q.; Zibetti, S.; Bertoldi, F.; Biggs, A. D.; Chapman, S. C.; Dannerbauer, H.; Dunlop, J. S.; Gawiser, E.; Ivison, R. J.; Knudsen, K. K.; Kovacs, A.; Lacey, C. G.; Menten, K. M.; Padilla, N.; Rix, H.-W.; van der Werf, P. P.

    2012-02-01

    SMGs typically have faint optical and near-IR counterparts (e.g. Ivison et al. 2002MNRAS.337....1I), so we require deep photometry for accurate photometric redshift estimates. The ECDF-S was chosen for this survey because it is an exceptionally well-studied field and as such we are able to utilize data from extensive archival imaging and spectroscopic surveys. For completeness and uniformity, we only consider surveys that cover a large fraction of the ECDF-S rather than the smaller and deeper central Chandra Deep Field-South (CDF-S) region. Therefore, we utilize the MUltiwavelength Survey by Yale-Chile (MUSYC; Gawiser et al. 2006, Cat. J/ApJS/162/1) near-IR survey for U- to K-band imaging (Taylor et al. 2009, Cat. J/ApJS/183/295), and the Spitzer IRAC/MUSYC Public Legacy in ECDF-S (SIMPLE) imaging for Spitzer IRAC data (Damen et al. 2011, cat. J/ApJ/727/1). We also include U-band data from the deep GOODS/VIMOS imaging survey of the CDF-S (Nonino et al. 2009ApJS..183..244N); although this covers only ~60 per cent of LESS SMGs, it is valuable for galaxies that are undetected at short wavelengths in the shallower MUSYC survey. In addition, we have carried out deep near-IR observations in the J and Ks bands with the HAWK-I at the ESO-VLT (ID: 082.A-0890, PI: N. Padilla). (2 data files).

  12. Notes from the field: malnutrition and elevated mortality among refugees from South Sudan - Ethiopia, June-July 2014.

    PubMed

    Andresen, Ellen; Bilukha, Oleg O; Menkir, Zeray; Gayford, Megan; Kavosa, Millicent; Wtsadik, Mulugeta; Maina, Gidraf; Gose, Mesfin; Nyagucha, Irene; Shahpar, Cyrus

    2014-08-15

    As a result of armed civil conflict in South Sudan that started in mid-December of 2013, an estimated 1.1 million persons were internally displaced, and approximately 400,000 refugees fled South Sudan to neighboring countries (primarily to Ethiopia, Uganda, Sudan, and Kenya). Refugees from South Sudan arriving in Ethiopia are sheltered in three refugee camps located in Gambella region: Leitchuor, Kule, and Tierkidi. The camps were established during January-May 2014 and have estimated refugee populations of 47,000, 51,000, and 50,000, respectively. Reports from health clinics and humanitarian agencies providing assistance to refugees suggested poor nutritional status of arriving refugees and elevated mortality rates. To assess the nutritional status of refugee children aged 6-59 months and mortality rates (crude [all ages] and aged <5 years), the Administration for Refugee and Returnee Affairs (an Ethiopian government aid agency), the United Nations High Commissioner for Refugees, World Food Programme, and United Nations Children's Fund, in collaboration with CDC, conducted cross-sectional population-representative surveys in Leitchuor, Kule, and Tierkidi camps during June-July 2014. Anthropometric measurements in children were taken using standard procedures, and nutritional status was classified based on 2006 World Health Organization (WHO) growth standards. Hemoglobin was measured using HemoCue Hb 301. Anemia was diagnosed according to WHO thresholds. Retrospective mortality rates in Leitchuor and Kule were measured using a household census method.

  13. Consolidation of geologic studies of geopressured-geothermal resources in Texas: Barrier-bar tidal-channel reservoir facies architecture, Jackson Group, Prado field, South Texas; Final report

    SciTech Connect

    Seni, S.J.; Choh, S.J.

    1994-01-01

    Sandstone reservoirs in the Jackson barrier/strandplain play are characterized by low recovery efficiencies and thus contain a large hydrocarbon resource target potentially amenable to advanced recovery techniques. Prado field, Jim Hogg County, South Texas, has produced over 23 million bbl of oil and over 32 million mcf gas from combination structural-stratigraphic traps in the Eocene lower Jackson Group. Hydrocarbon entrapment at Prado field is a result of anticlinal nosing by differential compaction and updip pinch-out of barrier bar sandstone. Relative base-level lowering resulted in forced regression that established lower Jackson shoreline sandstones in a relatively distal location in central Jim Hogg County. Reservoir sand bodies at Prado field comprise complex assemblages of barrier-bar, tidal-inlet fill, back-barrier bar, and shoreface environments. Subsequent progradation built the barrier-bar system seaward 1 to 2 mi. Within the barrier-bar system, favorable targets for hydrocarbon reexploration are concentrated in tidal-inlet facies because they possess the greatest degree of depositional heterogeneity. The purpose of this report is (1) to describe and analyze the sand-body architecture, depositional facies variations, and structure of Prado field, (2) to determine controls on distribution of hydrocarbons pertinent to reexploration for bypassed hydrocarbons, (3) to describe reservoir models at Prado field, and (4) to develop new data affecting the suitability of Jackson oil fields as possible candidates for thermally enhanced recovery of medium to heavy oil.

  14. Tracing the Mass-Dependent Star Formation History of Late-Type Galaxies using X-ray Emission: Results from the CHANDRA Deep Fields

    NASA Technical Reports Server (NTRS)

    Lehmer, B.D; Brandt, W.N.; Schneider, D.P.; Steffen, A.T.; Alexander, D.M.; Bell, E.F.; Hornschemeier, A.E.; McIntosh, D.H.; Bauer, F.E.; Gilli, R.; Mainieri, V.; Silverman, J.D.; Tozzi, P.; Wolf, C.

    2008-01-01

    We report on the X-ray evolution over the last approx.9 Gyr of cosmic history (i.e., since z = 1.4) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N and E-CDF-S. respectively; jointly CDFs) survey fields. Our late-type galaxy sample consists of 2568 galaxies. which were identified using rest-frame optical colors and HST morphologies. We utilized X-ray stacking analyses to investigate the X-ray emission from these galaxies, emphasizing the contributions from normal galaxies that are not dominated by active galactic nuclei (AGNs). Over this redshift range, we find significant increases (factors of approx. 5-10) in the X-ray-to-optical mean luminosity ratio (L(sub x)/L(sub B)) and the X-ray-to-stellar-mass mean ratio (L(sub x)/M(sub *)) for galaxy populations selected by L(sub B) and M(sub *), respectively. When analyzing galaxy samples selected via SFR, we find that the mean X-ray-to-SFR ratio (L(sub x)/SFR) is consistent with being constant over the entire redshift range for galaxies with SFR = 1-100 Solar Mass/yr, thus demonstrating that X-ray emission can be used as a robust indicator of star-formation activity out to z approx. 1.4. We find that the star-formation activity (as traced by X-ray luminosity) per unit stellar mass in a given redshift bin increases with decreasing stellar mass over the redshift range z = 0.2-1, which is consistent with previous studies of how star-formation activity depends on stellar mass. Finally, we extend our X-ray analyses to Lyman break galaxies at z approx. 3 and estimate that L(sub x)/L(sub B) at z approx. 3 is similar to its value at z = 1.4.

  15. South-to-North, cross-disciplinary training in global health practice: ten years of lessons learned from an infectious disease field course in Jamaica.

    PubMed

    Scarlett, Henroy P; Nisbett, Richard A; Stoler, Justin; Bain, Brendan C; Bhatta, Madhav P; Castle, Trevor; Harbertson, Judith; Brodine, Stephanie K; Vermund, Sten H

    2011-09-01

    Global commerce, travel, and emerging and resurging infectious diseases have increased awareness of global health threats and opportunities for collaborative and service learning. We review course materials, knowledge archives, data management archives, and student evaluations for the first 10 years of an intensive summer field course in infectious disease epidemiology and surveillance offered in Jamaica. We have trained 300 students from 28 countries through collaboration between the University of the West Indies and U.S. partner universities. Participants were primarily graduate students in public health, but also included health professionals with terminal degrees, and public health nurses and inspectors. Strong institutional synergies, committed faculty, an emphasis on scientific and cultural competencies, and use of team-based field research projects culminate in a unique training environment that provides participants with career-developing experiences. We share lessons learned over the past decade, and conclude that South-to-North leadership is critical in shaping transdisciplinary, cross-cultural, global health practice.

  16. Field-trip guide to volcanic and volcaniclastic deposits of the lower Jurassic Talkeetna formation, Sheep Mountain, south-central Alaska

    USGS Publications Warehouse

    Draut, Amy E.; Clift, Peter D.; Blodgett, Robert B.

    2006-01-01

    This guide provides information for a one-day field trip in the vicinity of Sheep Mountain, just north of the Glenn Highway in south-central Alaska. The Lower Jurassic Talkeetna Formation, consisting of extrusive volcanic and volcaniclastic sedimentary rocks of the Talkeetna arc complex, is exposed on and near Sheep Mountain. Field-trip stops within short walking distance of the Glenn Highway (approximately two hours’ drive from Anchorage) are described, which will be visited during the Geological Society of America Penrose meeting entitled Crustal Genesis and Evolution: Focus on Arc Lower Crust and Shallow Mantle, held in Valdez, Alaska, in July 2006. Several additional exposures of the Talkeetna Formation on other parts of Sheep Mountain that would need to be accessed with longer and more strenuous walking or by helicopter are also mentioned.

  17. DC and Wave Electric Fields and Other Plasma Parameters Observed on Two Sounding Rockets in the Dark Cusp during IMF BZ North and South Conditions

    NASA Technical Reports Server (NTRS)

    Pfaff, R. F.; Bounds, S.; Acuna, M.; Maynard, N. C.; Moen, J.; Egeland, A.; Holtet, J.; Maseide, K.; Sandholt, P. E.; Soraas, F.

    1999-01-01

    Two Black Brant IX sounding rockets were launched into the dark, dayside cusp near magnetic noon on December 2 and 3, 1997, from Ny Alesund, Spitzbergen at 79degN reaching altitudes of approximately 450 km. Real-time ground-based and Wind (interplanetary magnetic field) IMF data were used to determine the launch conditions. The first launch, with Bz north conditions, crossed into and back out of an open field region with merging poleward of the projected trajectory. The second flight, into Bz south conditions, was timed to coincide with an enhancement in the merging rate from a increase in the negative Bz, while the (Defense Meteorological Satellite Program) DMSP F13 satellite was situated slightly to the north of the rocket trajectory. Each payload returned DC electric and magnetic fields, plasma waves, energetic particles, photometer data, and thermal plasma data. Data from both flights will be shown, with an emphasis on the DC electric field results. In particular, the data gathered on December 2, 1997 will be used to discuss ionospheric signatures of merging and the open/closed character of the the cusp/low latitude boundary layer. In contrast, the data gathered on December 3, 1997 shows evidence of pulsed electric field structures which will be examined in the context of cusp plasma entry processes. Both data sets returned a rich variety of plasma waves, as well as optical emissions and thermal plasma data.

  18. South Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image of South Africa was acquired on May 14, 2000, by NASA's Moderate-resolution Imaging Spectroradiometer, or MODIS. The image was produced using a combination of the sensor's 250-m and 500-m resolution visible wavelength bands. As part of the opening ceremony to begin the joint U.S.-South Africa SAFARI Field Experiment, NASA presented print copies of this image as GIFts to Dr. Ben Ngubane, Minister of Arts, Science and Technology, and Honorable Advocate Ngoaka Ramathlodi, Premier of the Northern Province, South Africa. The area shown in this image encompasses seven capital cities and a number of the region's distinctive geological features can be seen clearly. Toward the northern (top) central part of the image, the browns and tans comprise the Kalahari Desert of southern Botswana. The Tropic of Capricorn runs right through the heart of the Kalahari and the Botswanan capital city of Gaborone sits on the Limpopo River, southeast of the Kalahari. Along the western coastline of the continent is the country of Namibia, where the Namib Desert is framed against the sea by the Kaokoveld Mountains. The Namibian capital of Windhoek is obscured by clouds. Looking closely in the center of the image, the Orange River can be seen running from east to west, demarcating the boundary between Namibia and South Africa. On the southwestern corner of the continent is the hook-like Cape of Good Hope peninsula and Cape Town, the parliamentary capital of South Africa. Running west to east away from Cape Town are the Great Karroo Mountains. The shadow in this image conveys a sense of the very steep grade of the cliffs along the southern coast of South Africa. Port Elizabeth sits on the southeasternmost point of South Africa, and a large phytoplankton bloom can be seen in the water about 100 miles east of there. Moving northward along the east coast, the Drakensberg Mountains are visible. The two small nations of Lesotho and Swaziland are in this region, completely

  19. A classification of the sea level pressure daily fields in southern South America: an application to daily rainfall in the Pampas region.

    NASA Astrophysics Data System (ADS)

    Penalba, Olga; Bettolli, Maria Laura

    2010-05-01

    The Pampas covers Argentina's most productive agricultural land, extending more than 1600 km in the heartland of the country. The impact of climate adversities on agricultural activities makes it necessary to determine to what extent climate spatial and temporal variability is responsible for crop yields and to generate elements to monitor, estimate impacts and design an alert system. Local atmospheric conditions depend, among other factors, on the major scale fields. Consequently, an objective classification of daily circulation fields in the South of South America is proposed using a long database. Daily rainfalls within the Argentine Humid Pampas are also investigated in connection to the weather type categories. Daily mean sea level pressure (SLP) fields corresponding to the NCEP_Reanalysis 2 data provided by the NCEP-NCAR were used as representative of atmospheric circulation at low levels which is of great importance in determining moisture advection in the region. The period of study was 1979-1999. The chosen domain extends from 15°S to 60°S and from 40°W to 90° W on a 2.5° latitude-longitude grid. This domain extends over the Pacific and the Atlantic Oceans and the Andes Mountains, all of which have a significant influence on the atmospheric circulation over South America. The analyzed seasons correspond to summer (December-January- February) and winter (June-July-August). Daily rainfall series located in the core region for growing different crops in the Argentine Humid Pampas were also used. These series were provided by the Argentine National Meteorological Service. Cluster analysis was performed coupled with Principal Component Analysis (PCA) to determine the atmospheric circulation patterns. PCA was used as a synthesis method and the cluster analysis was carried out in the subspace given by the leading unrotated principal components. The ‘k-means' partitioning method with Euclidean distance was used. The choice of the optimal number of clusters

  20. Fracture development in Paleozoic shale of Chongqing area (South China). Part two: Numerical simulation of tectonic stress field and prediction of fractures distribution

    NASA Astrophysics Data System (ADS)

    Zeng, Weite; Ding, Wenlong; Zhang, Jinchuan; Zhang, Yeqian; Guo, Ling; Jiu, Kai; Li, Yifan

    2013-10-01

    A tectonics sedimentation evolution has been researched in Southeast Chongqing, and the reasonable Longmaxi shale highstand system tract (HST) and transgressive system tract (TST) geological model were built respectively based on the rock mechanical test and acoustic emission experiment which the samples are from field outcrop and the Yuye-1 well. The Longmaxi shale two-dimension tectonic stress field during the Cenozoic was simulated by the finite element method, and the distribution of fractures was predicted. The research results show that the tectonic stress field and the distribution of fractures were controlled by lithology and structure. As a result of Cretaceous movement, there are trough-like folds (wide spaced synclines), battlement-like folds (similar spaces between synclines and anticlines) and ejective folds (wide spaced anticlines), which are regularly distributed from southeast to northwest in the study area. Since the strain rate and other physical factors such as the viscosity are not taken into account, and the stress intensity is the main factor that determines the tectonic strength. Therefore, the stronger tectonic strength leads the higher stress intensity in the eastern and southeastern study area than in the northwest. The fracture zones are mainly concentrated in the fold axis, transition locations of faults and folds, the regions where are adjacent to faults. The fragile mineral contents (such as siliceous rock, carbonate rock and feldspar) in the shelf facies shale from south of the study area are higher than in the bathyal facies and abyssal facies shale from center of the study area. The shales characterized by low Poisson's ratio and high elastic modulus from south of the study area are easily broken during Cenozoic orogenic movement.

  1. DC and Wave Electric Fields and Other Plasma Parameters Observed on Two Sounding Rockets in the Dark Cusp During IMF Bz North and South Conditions

    NASA Technical Reports Server (NTRS)

    Pfaff, R. F.; Acuna, M.; Bounds, S.; Farrell, W.; Freudenreich, H.; Lepping, R.; Vondrak, R.; Maynard, N. C.; Moen, J.; Egeland, A.

    1997-01-01

    Two Black Brant IX sounding rockets were launched into the dark, dayside cusp near magnetic noon on December 2 and 3, 1997, from Ny Alesund, Spitzbergen at 79 N reaching altitudes of approximately 450 km. Real-time ground-based and Wind IMF data were used to determine the launch conditions. The first launch, with Bz north conditions, crossed into and back out of an open field region with merging poleward of the projected trajectory. The second flight, into Bz south conditions, was timed to coincide with an enhancement in the merging rate from a increase in the negative Bz, while the DMSP F13 satellite was situated slightly to the north of the rocket trajectory. Each payload returned DC electric and magnetic fields, plasma waves, energetic particles, photometer data, and thermal plasma data. Data from both flights will be shown, with an emphasis on the DC electric field results. In particular, the data gathered on December 2, 1997 will be used to discuss ionospheric signatures of merging and the open/closed character of the the cusp/low latitude boundary layer. In contrast, the data gathered on December 3, 1997 shows evidence of pulsed electric field structures which will be examined in the context of cusp plasma entry processes. Both data sets returned a rich variety of plasma waves, as well as optical emissions and thermal plasma data.

  2. DC and Wave Electric Fields and Other Plasma Parameters Observed on Two Sounding Rockets in the Dark Cusp during IMF Bz North and South Conditions

    NASA Technical Reports Server (NTRS)

    Pfaff, R. F.; Acuna, M.; Bounds, S.; Farrell, W.; Freudenreich, W.; Lepping, R.; Vondrak, R.; Maynard, N. C.; Moen, J.; Egeland, A.

    1999-01-01

    Two Black Brant IX sounding rockets were launched into the dark, dayside cusp near magnetic noon on December 2 and 3, 1997, from Ny Alesund, Spitzbergen at 79 deg N reaching altitudes of about 450 km. Real-time ground-based and Wind IMF data were used to determine the launch conditions. The first launch, with Bz north conditions, crossed into and back out of an open field region with merging poleward of the projected trajectory. The second flight, into Bz south conditions, was timed to coincide with an enhancement in the merging rate from a increase in the negative Bz, while the DMSP Fl 3 satellite was situated slightly to the north of the rocket trajectory. Each payload returned DC electric and magnetic fields, plasma waves, energetic particles, photometer data, and thermal plasma data. Data from both flights will be shown, with an emphasis on the DC electric field results. In particular, the data gathered on December 2, 1997 will be used to discuss ionospheric signatures of merging and the open/closed character of the the cusp/low latitude boundary layer. In contrast, the data gathered on December 3, 1997 shows evidence of pulsed electric field structures which will be examined in the context of cusp plasma entry processes. Both data sets returned a rich variety of plasma waves, as well as optical emissions and thermal plasma data.

  3. Arsenic accumulation and phosphorus status in two rice (Oryza sativa L.) cultivars surveyed from fields in South China.

    PubMed

    Lu, Ying; Dong, Fei; Deacon, Claire; Chen, Huo-Jun; Raab, Andrea; Meharg, Andrew A

    2010-05-01

    The consumption of paddy rice (Oryza sativa L.) is a major inorganic arsenic exposure pathway in S.E. Asia. A multi-location survey was undertaken in Guangdong Province, South China to assess arsenic accumulation and speciation in 2 rice cultivars, one an Indica and the other a hybrid Indica. The results showed that arsenic concentrations in rice tissue increased in the order grain < husk < straw < root. Rice grain arsenic content of 2 rice cultivars was significant different and correlated with phosphorus concentration and molar ratio of P/As in shoot, being higher for the Indica cultivar than for the hybrid Indica, which suggests altering shoot phosphorus status as a promising route for breeding rice cultivars with reduced grain arsenic. Speciation of grain arsenic, performed using HPLC-ICP-MS, identified inorganic arsenic as the dominant arsenic species present in the rice grain.

  4. Phylogenetic analysis of classical swine fever virus (CSFV) field isolates from outbreaks in South and Central America.

    PubMed

    Pereda, A J; Greiser-Wilke, I; Schmitt, B; Rincon, M A; Mogollon, J D; Sabogal, Z Y; Lora, A M; Sanguinetti, H; Piccone, M E

    2005-06-01

    To date, there is little information concerning the epidemiological situation of classical swine fever (CSF) in the Americas. Besides summarizing the available data, genotyping of isolates from outbreaks in domestic pigs in several countries of South and Central America was performed. For this, a 190 base fragment of the E2 envelope glycoprotein gene was used. European strains and isolates, and historical isolates from the United States (US) were included for comparison. In contrast to the situation in most parts of Europe, where group 2 isolates predominate, it was found that all the isolates from the American continent analyzed belonged to group 1 and were further resolved into three subgroups. The Cuban isolates clustered in subgroup 1.2, whereas the isolates from Honduras and Guatemala clustered in subgroup 1.3. The remaining isolates from Argentina, Brazil, Colombia and Mexico generated four poorly resolved clusters in subgroup 1.1, together with the vaccine strains, with historical European and US isolates, and with a recent Russian isolate. While the vaccine strains and the historical European isolates formed a relatively distinct cluster, one of the US isolates clustered together with the Mexican, and another one with Colombian isolates. Historically, CSF (hog cholera) was observed almost simultaneously in the US and in Europe in the first half of the 19th century, and its origin remains a matter of discussion. Our results showed that the US isolates are closely related to isolates from South America, while appearance of isolates in Cuba on one hand and in Honduras and Guatemala on the other hand, seems to have been due to unrelated events. This allows to speculate that at least in the American continent, CSF virus may have appeared independently in several regions, and spreading may have been a secondary effect.

  5. An Integrated Study of the Grayburg/San Andres Reservoir, Foster and South Cowden Fields, Ector County, Texas, Class II

    SciTech Connect

    Trentham, Robert C.; Weinbrandt, Richard; Robinson, William C.; Widner, Kevin

    2001-05-03

    The objectives of the project were to: (1) Thoroughly understand the 60-year history of the field. (2) Develop a reservoir description using geology and 3D seismic. (3) Isolate the upper Grayburg in wells producing from multiple intervals to stop cross flow. (4) Re-align and optimize the upper Grayburg waterflood. (5) Determine well condition, identify re-frac candidates, evaluate the effectiveness of well work and obtain bottom hole pressure data for simulation utilizing pressure transient testing field wide. (6) Quantitatively integrate all the data to guide the field operations, including identification of new well locations utilizing reservoir simulation.

  6. Development of a Spatially Targeted Field Sampling Technique for the Southern Cattle Tick, Rhipicephalus microplus, by Mapping Whitetailed Deer, Odocoileus virginianus, Habitat in South Texas

    PubMed Central

    Phillips, Pamela L.; Welch, John B.; Kramer, Matthew

    2014-01-01

    The objective of our study was to determine whether satellite remote sensed data could be used to identify white-tailed deer, Odocoileus virginianus (Zimmerman) (Artiodactyla: Cervidae), habitat and target locations for sampling free-living larvae of the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Ixodida: Ixodidae) in South Texas. Two methods for mapping white-tailed deer habitat were used, an object-oriented method to identify closed canopies and waterways for deer movement and two vegetation indices: the Normalized Difference Vegetation Index and the Modified Soil Adjusted Vegetation Index to identify forage for deer. These two data sets of favorable white-tailed deer habitat were combined within a geographic information system to identify locations for sampling ticks. Larvae of R. (B.) microplus, were sampled in Zapata County, Texas, by walking transects with attached flannel panels to jeans. Although the data set and sampling period were limited, data analysis demonstrated that sampling of free-living larvae of R. (B.) microplus can be conducted in South Texas, and larvae were most abundant in areas that harbored O. virginianus. Spatial analysis of satellite imagery to classify white-tailed deer/southern cattle tick habitat proved efficacious and may be useful in directing sampling activities in the field. PMID:25368044

  7. Development of a spatially targeted field sampling technique for the southern cattle tick, Rhipicephalus microplus, by mapping white-tailed deer, Odocoileus virginianus, habitat in South Texas.

    PubMed

    Phillips, Pamela L; Welch, John B; Kramer, Matthew

    2014-01-01

    The objective of our study was to determine whether satellite remote sensed data could be used to identify white-tailed deer, Odocoileus virginianus (Zimmerman) (Artiodactyla: Cervidae), habitat and target locations for sampling free-living larvae of the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Ixodida: Ixodidae) in South Texas. Two methods for mapping white-tailed deer habitat were used, an object-oriented method to identify closed canopies and waterways for deer movement and two vegetation indices: the Normalized Difference Vegetation Index and the Modified Soil Adjusted Vegetation Index to identify forage for deer. These two data sets of favorable white-tailed deer habitat were combined within a geographic information system to identify locations for sampling ticks. Larvae of R. (B.) microplus, were sampled in Zapata County, Texas, by walking transects with attached flannel panels to jeans. Although the data set and sampling period were limited, data analysis demonstrated that sampling of free-living larvae of R. (B.) microplus can be conducted in South Texas, and larvae were most abundant in areas that harbored O. virginianus. Spatial analysis of satellite imagery to classify white-tailed deer/southern cattle tick habitat proved efficacious and may be useful in directing sampling activities in the field.

  8. First Results from the 7 Ms Chandra Deep Field-South Survey: A Good Hard Look at Growing Supermassive Black Holes in the Distant Universe

    NASA Astrophysics Data System (ADS)

    Brandt, William; Chandra Deep Fields Team

    2017-01-01

    Sensitive cosmic X-ray surveys with the Chandra, XMM-Newton, and now NuSTAR observatories have revolutionized our ability to find and study distant active galactic nuclei (AGNs), the main sites of supermassive black hole growth in the Universe. I will describe some recent discoveries about the demographics, physics, and ecology of distant AGNs coming from the deepest Chandra survey to date, the 7 Ms Chandra Deep Field-South. Some specific topics covered will include (1) robust X-ray spectral and variability characterization of the AGNs producing most of cosmic accretion power; (2) the demographics of AGNs in the first galaxies as revealed by direct detection and stacking; and (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs. I will also briefly describe other remarkable discoveries coming from this survey; e.g., measurements of the evolving X-ray binary populations of normal and starburst galaxies.

  9. Monitoring PAH contamination in the field (South west Iberian Peninsula): biomonitoring using fluorescence spectrophotometry and physiological assessments in the shore crab Carcinus maenas (L.) (Crustacea: Decapoda).

    PubMed

    Dissanayake, Awantha; Bamber, Shaw D

    2010-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants of the marine environment, arising predominantly from petrochemical contamination and pyrogenic sources. A biomarker of PAH exposure was employed in a field study (South West, Spain) in both captured (indigenous) and deployed (caged) shore crabs (Carcinus maenas) in the chronic PAH-exposed Bays of Algeciras and Gibraltar (from associated harbour and boating activity) compared to a relatively 'clean' site (Cadiz). Metabolite fluorescence was attributed to the following key priority PAH groups; naphthalenes (NAPs), pyrenes (PYRs) and benzo[a]pyrenes (BAPs). Temporal variability was assessed using deployed populations over an eight week period. Petrogenic and pyrogenic PAH contamination (as an indicator of the PAH type) was demonstrated using a ratio between FF(BAP + PYR)/FF(NAP). Physiological assessments from deployed crabs demonstrated both physiological and cellular alterations as shown by reduced heart rates (at rest) and increased cellular stress in crabs from the PAH contaminated sites.

  10. Exploring the Usefulness of MISR-HR Products to Estimate Maize Crop Extent and Using Field Evidence to Evaluate the Results in South Africa's Free State Province

    NASA Astrophysics Data System (ADS)

    Verstraete, M. M.; Knox, N. M.; Hunt, L. A.; Kleyn, L.

    2014-12-01

    The MISR instrument on NASA's Terra platform has been operating for almost 15 years. Standard products are generated at a spatial resolution of 1.1 km or coarser, but a recently developed method to re-analyze the Level-1B2 data allows the retrieval of biogeophysical products at the native spatial resolution of the instrument (275 m). This development opens new opportunities to better address issues such as the management of agricultural production and food security. South African maize production is of great economic and social importance, not only nationally, but on the global market too, being one of the top ten maize producing countries. Seasonal maize production statistics are currently based on a combination of field measurements and estimates derived from manually digitizing high resolution imagery from the SPOT satellite. The field measurements are collected using the Producer Independent Crop Estimate System (PICES) developed by Crop Estimates Committee of the Department of Agriculture, Forestry and Fisheries. There is a strong desire to improve the quality of these statistics, to generate those earlier, and to automate the process to encompass larger areas. This paper will explore the feasibility of using the MISR-HR spectral and directional products, combined with the finer spatial resolution and the relatively frequent coverage afforded by that instrument, to address these needs. The study area is based in the Free State, South Africa, one of the primary maize growing areas in the country, and took place during the 2012-2013 summer growing season. The significance of the outcomes will be evaluated in the context of the 14+ years of available MISR data.

  11. Progressive and self-limiting neurodegenerative disorders in Africa: a new prominent field of research led by South Africa but without strong health policy

    PubMed Central

    Poreau, Brice

    2016-01-01

    Introduction Neurodegenerative disorders are involved in mortality and morbidity of every country. A high prevalence is estimated in Africa. Neurodegenerative disorders are defined by a progressive or self-limiting alteration of neurons implied in specific functional and anatomical functions. It encompasses a various range of clinical disorders from self-limiting to progressive. Focus on public health policies and scientific research is needed to understand the mechanisms to reduce this high prevalence. We use bibliometrics and mapping tools to explore the area studies and countries involved in scientific research on neurodegenerative disorders in Africa. Methods We used two databases: Web of Science and Pubmed. We analyzed the journals, most cited articles, authors, publication years, organizations, funding agencies, countries and keywords in Web of Science Core collection database and publication years and Medical Subject Headings in Pubmed database. We mapped the data using VOSviewer. Results We accessed 44 articles published between 1975 and 2014 in Web of Science Core collection Database and 669 from Pubmed database. The majority of which were after 2006. The main countries involved in research on neurodegenerative disorders in Africa the USA, the United Kingdom, France and South Africa representing the main network collaboration. Clinical neurology and Genetics hereditary are the main Web of Science categories whereas Neurosciences and Biochemistry and Molecular Biology are the main Web of Science categories for the general search “neurodegenerative disorders” not restrained to Africa. This is confirmed by Medical Subject Headings analysis from Pubmed with one more area study: Treatment. Conclusion Neurodegenerative disorders research is leaded by South Africa with a network involving the USA, the UK, as well as African countries such Zambia. The chief field that emerged was on patient and hereditary as well as treatment. Public health policies were

  12. A field test for competitive effects of Aedes albopictus on A. aegypti in South Florida: differences between sites of coexistence and exclusion?

    PubMed Central

    Juliano, Steven A.; Lounibos, L. Philip; O’Meara, George F.

    2007-01-01

    We tested whether interspecific competition from Aedes albopictus had measurable effects on A. aegypti at the typical numbers of larval mosquitoes found in cemetery vases in south Florida. We also tested whether the effect of interspecific competition from A. albopictus on A. aegypti differed between sites where A. aegypti either persists or went extinct following invasion by A. albopictus. Similar experiments manipulating numbers of A. albopictus in cemetery vases were conducted at three sites of A. aegypti persistence and three sites where A. aegypti was apparently extinct. The experiments were done using numbers of larvae that were determined by observed numbers of larvae for each site, and with resources (leaf detritus) that accumulated in experimental vases placed into each field site. In both the early rainy season (when number of mosquito larvae was low) and the late rainy season (when number of mosquito larvae was high), there was a significant effect of treatment on developmental progress of experimental A. aegypti. In the late rainy season, when numbers of larvae were high, there was also a significant effect of treatment on survivorship of A. aegypti. However, the competition treatment × site type (A. aegypti persists vs extinct) interaction was never significant, indicating that the competitive effect of A. albopictus on A. aegypti did not differ systematically between persistence versus extinction sites. Thus, although competition from A. albopictus is strong under field conditions at all sites, we find no evidence that variation in the impact of interspecific competition is associated with coexistence or exclusion. Interspecific competition among larvae is thus a viable explanation for exclusion or reduction of A. aegypti in south Florida, but variation in the persistence of A. aegypti following invasion does not seem to be primarily a product of variation in the conditions in the aquatic environments of cemetery vases. PMID:15024640

  13. Distribution of Pleuroncodes monodon larvae over the continental shelf of south-central Chile: Field and modeling evidence for partial local retention and transport

    NASA Astrophysics Data System (ADS)

    Yannicelli, Beatriz; Castro, Leonardo; Parada, Carolina; Schneider, Wolfgang; Colas, Francois; Donoso, David

    2012-01-01

    In situ and modeled spatial distribution of squat lobster ( Pleuroncodes monodon) larvae over the continental shelf off south central Chile (35-37°S) was analyzed along with currents and hydrography. We aimed to identify the main larval transport/retention characteristics in the study area, which constitutes the southernmost P. monodon fishing grounds embedded in the Humboldt Current System. We hypothesized that the main contribution to population renewal originates in the two persistent adult aggregations close to the nursery ground that occurs over a continental shelf terrace limited by two submarine canyons. Two extensive bio-physical field campaigns were carried out during the main 2001-2002 upwelling season field data indicated that larvae were released from late austral winter to spring from spots to the north and south of the nursery. Zoea I were found mainly below 50 m depth in southward-flowing waters, whereas older zoea dominated in northward flowing layers above 50 m. Larvae were circumscribed between the coast and the shelf break front and pelagic retention areas were identified over the widest shelf area. Megalopa and juveniles during March, were only found over the nursery area. Individual based simulations coupled to the output of a hydrodynamic model (climatological configuration) for the studied area, showed that the release sites close to the nursery made the largest contribution to recruitment. Sites further north could also contribute to recruitment if hatching occurred later in the upwelling season. The contribution of vertical behavior to larval success was also important, as was the former’s interaction with the site and time of larval release. Our results support the relevance of coastal circulation (affected by topography) on the persistence of P. monodon populations off southern Chile, and the modulation of temporal variability. These results might apply to other abundant species in the area.

  14. Consolidation of geologic studies of geopressured-geothermal resources in Texas: Barrier-bar tidal-channel reservoir facies architecture, Jackson Group, Prado Field, South Texas

    SciTech Connect

    Seni, S.J.; Choh, S.J.

    1993-09-01

    Sandstone reservoirs in the Jackson barrier/strandplain play are characterized by low recovery efficiencies and thus contain a large hydrocarbon resource target potentially amenable to advanced recovery techniques. Prado field, Jim Hogg County, South Texas, has produced over 23 million bbl of oil and over 32 million mcf gas from combination structural-stratigraphic traps in the Eocene lower Jackson Group. Hydrocarbon entrapment at Prado field is a result of anticlinal nosing by differential compaction and updip pinch-out of barrier bar sandstone. Relative base-level lowering resulted in forced regression that established lower Jackson shoreline sandstones in a relatively distal location in central Jim Hogg County. Reservoir sand bodies at Prado field comprise complex assemblages of barrier-bar, tidal-inlet fill, back-barrier bar, and shoreface environments. Subsequent progradation built the barrier-bar system seaward 1 to 2 mi. With the barrier-bar system, favorable targets for hydrocarbon reexploration are concentrated in tidal-inlet facies because they possess the greatest degree of depositional heterogeneity.

  15. Seasonal and diurnal variations of atmospheric PAHs and OCPs in a suburban paddy field, South China: Impacts of meteorological parameters and sources

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Li, Qilu; Wang, Shaorui; Wang, Yujie; Luo, Chunling; Li, Jun; Zhang, Gan

    2015-07-01

    The atmospheric contaminations of polycyclic aromatic hydrocarbons (PAHs), hexachlorocyclohexanes (HCHs), and DDTs have been extensively monitored for decades, but contaminations in agricultural paddy fields have rarely been reported. We measured the atmospheric PAH, HCH, and DDT constituents during different rice growth stages in a suburban paddy field in South China. Diurnal variations were found in the atmospheric concentrations of PAHs and HCHs, but not for DDTs. Additional nocturnal emissions and meteorological conditions, such as low nocturnal stable atmospheric boundary layers, may be mainly responsible for the higher PAH and HCH levels at night, respectively. Atmospheric concentrations of PAH, HCH, and DDT constituents varied with rice growth stage, but no regular seasonal variation was found, suggesting that rice growth has no significant influence on the atmospheric concentrations of these chemicals. A correlation analysis suggested that meteorological parameters, such as temperature, precipitation, mixing layer height, or wind speed, may directly or indirectly affect the air concentrations of PAHs, HCHs, and DDTs. Source apportionment showed that atmospheric PAHs, HCHs, and DDTs in the paddy field originated from mixed sources, and the contribution of each source varied with time. The isomer ratio of fluoranthene/(fluoranthene + pyrene) may result in an invalid diagnosis of PAHs.

  16. Geological record of tsunami inundations in Pantano Morghella (south-eastern Sicily) both from near and far-field sources

    NASA Astrophysics Data System (ADS)

    Gerardi, F.; Smedile, A.; Pirrotta, C.; Barbano, M. S.; De Martini, P. M.; Pinzi, S.; Gueli, A. M.; Ristuccia, G. M.; Stella, G.; Troja, S. O.

    2012-04-01

    Analysis of tsunami deposits from the Pantano Morghella area provided geological evidence for two inundations occurred along the south-eastern Ionian coast of Sicily. Pantano Morghella is a large pond characterised by a fine-grained sedimentation indicating a low-energy depositional environment. Two anomalous yellow sandy layers found at different depths indicate the occurrence of high-energy marine inundations. We studied sedimentological and paleontological features of the anomalous deposits as well as their spatial distribution observing the following properties: different facies with respect to the local stratigraphic sequence; erosive bases, rip-up clasts and broken elements testifying violent deposition mechanisms; macro and micro fauna of marine environment; relatively constant thickness throughout most of the depositional zone with thinning at the distal end; large sand sheets that extend inland. These observations, jointly with their infrequency in the sedimentary record and the age indicating a fast deposition, provided strong evidence for tsunami inundations. Correlations between anomalous layers and historical tsunamis are supported by radiocarbon and OSL dating results. The younger deposit is likely due to the 1908 near-source tsunami, whereas the flooding of the oldest event is most likely associated with a far and large source, the Crete 365 AD earthquake.

  17. Notes from the field: chikungunya virus spreads in the Americas - Caribbean and South America, 2013-2014.

    PubMed

    Fischer, Marc; Staples, J Erin

    2014-06-06

    In December 2013, the World Health Organization reported the first local transmission of chikungunya virus in the Western Hemisphere, with autochthonous cases identified in Saint Martin. Since then, local transmission has been identified in 17 countries or territories in the Caribbean or South America (Anguilla, Antigua and Barbuda, British Virgin Islands, Dominica, Dominican Republic, French Guiana, Guadeloupe, Guyana, Haiti, Martinique, Puerto Rico, Saint Barthelemy, Saint Kitts and Nevis, Saint Lucia, Saint Martin, Saint Vincent and the Grenadines, and Sint Maarten). As of May 30, 2014, a total of 103,018 suspected and 4,406 laboratory-confirmed chikungunya cases had been reported from these areas. The number of reported cases nearly doubled during the previous 2 weeks. More than 95% of the cases have been reported from five jurisdictions: Dominican Republic (38,656 cases), Martinique (30,715), Guadeloupe (24,428), Haiti (6,318), and Saint Martin (4,113). The highest incidences have been reported from Saint Martin (115 cases per 1,000 population), Martinique (76 per 1,000), Saint Barthelemy (74 per 1,000), and Guadeloupe (52 per 1,000). Further expansion of these outbreaks and spread to other countries in the region is likely.

  18. Use of Potential Fields Data to Identify Petrological Controls on Seismicity within South-Central and Southeastern Alaska

    NASA Astrophysics Data System (ADS)

    Doser, D. I.; Veilleux, A. M.; Rodriguez, H.; de La Pena, A.; Mankhemthong, N.

    2010-12-01

    We have used data from regional gravity and aeromagnetic surveys to determine how variations in petrological properties of the upper plate(s) and subducting lower plate(s) influence the concentration of background seismicity in south-central and southeastern Alaska, as well as possible controls on asperities that ruptured during great earthquakes along the plate margin. In the Prince William Sound region it appears that seismicity concentrates at the edges of mafic and ultramafic bodies within the upper (North American) plate, while within Cook Inlet upper plate seismicity concentrates at the edges of a large serpentinite body. Rupture segmentation during the 1958 Fairweather earthquake in southeastern Alaska is associated with gravity highs along the Fairweather fault, while segmentation of the Queen Charlotte fault system appears related to changes in the structure of the Pacific plate. Although gravity coverage within the St. Elias region is sparse, background seismicity at depths of 10 to 20 km, including aftershocks of the 1979 Mw=7.4 St. Elias event, wraps around the edge of a gravity high located at the intersection of the Pamplona and Chugach-St. Elias fault systems. These results emphasize how additional gravity and magnetic data collection should be included as part of the upcoming Earthscope initiative in Alaska.

  19. Insights on the 2009 South Pacific tsunami in Samoa and Tonga from field surveys and numerical simulations

    NASA Astrophysics Data System (ADS)

    Fritz, Hermann M.; Borrero, Jose C.; Synolakis, Costas E.; Okal, Emile A.; Weiss, Robert; Titov, Vasily V.; Jaffe, Bruce E.; Foteinis, Spyros; Lynett, Patrick J.; Chan, I.-Chi; Liu, Philip L.-F.

    2011-07-01

    An M w ≈ 8.1 earthquake south of the Samoan Islands on 29 September 2009 generated a tsunami that killed 189 people. From 4 to 11 October, an International Tsunami Survey Team surveyed the seven major islands of the Samoan archipelago. The team measured locally focused runup heights of 17 m at Poloa and inundation of more than 500 m at Pago Pago. A follow-up expedition from 23 to 28 November surveying the three main islands of Tonga's northernmost Niua group revealed surprising 22 m runup and 1 km inundation. We analyze the extreme tsunami runup and complex impact distribution based on physical and societal observations combined with numerical modeling. That an outer rise/outer trench slope (OR/OTS) event is responsible for a tsunami disaster in the Pacific calls for care in identifying and defining tsunami hazards. Evacuation exercises conducted in Samoa in the preceding year may have limited the human toll; however, cars were identified as potential death traps during tsunami evacuations. This event highlights the extreme hazards from near source tsunamis when the earthquake's shaking constitutes the de facto warning, and further underscores the importance of community based education and awareness programs as essential in saving lives.

  20. Multiple episodes of dolomitization in the Arbuckle Group, Arbuckle Mountains, south-central Oklahoma: Field, petrographic, and geochemical evidence

    SciTech Connect

    Gao, G.; Land, L.S.; Elmore, R.D.

    1995-04-03

    The Cambro-Ordovician Arbuckle Group in the Arbuckle Mountains, south-central Oklahoma, had a complex history of dolomitization that resulted in two different geometries of dolomite bodies: stratal dolomite, of stratigraphically consistent, widespread distribution, and non-stratal dolomite, of stratigraphically inconsistent, local occurrence. Stratal dolomite includes the Royer and Butterly units in the lower Arbuckle Group. Most stratal dolomite samples are coarsely crystalline and have {sup 87}Sr/{sup 86}Sr ratios similar to Late Cambrian limestone and coeval seawater. All stratal dolomite and Arbuckle limestone samples have low {Delta}{sup 18}O values. Nonstratal dolomite is present in two areas: the Tishomingo Anticline and the Arbuckle Anticline. In the Tishomingo Anticline area, massive bodies (> 10 km{sup 2}) of nonstratal dolomite are present in a paleokarst system of pre-Middle Ordovician age. The petrographic and isotopic characteristics suggest that the nonstratal dolomite probably resulted from dolomitization of recrystallized limestone by post-Early Ordovician seawater. In the Arbuckle Anticline area, nonstratal dolomite is present as small irregular bodies that are related to Pennsylvanian faults and are associated with the margins of stratal Butterly dolomite. The nonstratal dolomite, medium to coarsely crystalline and brightly luminescent, is characterized by high {sup 87}Sr/{sup 86}Sr ratios values, and Fe and Mn concentrations, relative to all Arbuckle carbonates. Such compositions suggest that this type of dolomite probably originated from fluids that were derived from the adjacent basin(s) during late Paleozoic time.

  1. Establishing the role of detoxifying enzymes in field-evolved resistance to various insecticides in the brown planthopper (Nilaparvata lugens) in South India.

    PubMed

    Malathi, Vijayakumar Maheshwari; Jalali, Sushil K; Gowda, Dandinashivara K Sidde; Mohan, Muthugounder; Venkatesan, Thiruvengadam

    2017-02-01

    The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the major pests of rice throughout Asia. Extensive use of insecticides for suppressing N. lugens has resulted in the development of insecticide resistance leading to frequent control failures in the field. The aim of the present study was to evaluate resistance in the field populations of N. lugens from major rice growing states of South India to various insecticides. We also determined the activity of detoxifying enzymes (esterases [ESTs], glutathione S-transferases [GSTs], and mixed-function oxidases [MFOs]). Moderate levels of resistance were detected in the field populations to acephate, thiamethoxam and buprofezin (resistance factors 1.05-20.92 fold, 4.52-14.99 fold, and 1.00-18.09 fold, respectively) as compared with susceptible strain while there were low levels of resistance to imidacloprid (resistance factor 1.23-6.70 fold) and complete sensitivity to etofenoprox (resistance factor 1.05-1.66 fold). EST activities in the field populations were 1.06 to 3.09 times higher than the susceptible strain while for GST and MFO the ratios varied from 1.29 to 3.41 and 1.03 to 1.76, respectively. The EST activity was found to be correlated to acephate resistance (r = 0.999, P ≥ 0.001). The high selection pressure of organophosphate, neonicotinoid, and insect growth regulator (IGR) in the field is likely to be contributing for resistance in BPH to multiple insecticides, leading to control failures. The results obtained will be beneficial to IPM recommendations for the use of effective insecticides against BPH.

  2. Within and Between Field Movement of Diabrotica barberi and D. virgifera virgifera in the South Dakota Areawide Management Site

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dispersal is a way insects search for food, shelter, mates, oviposition sites, etc., and can ultimately result in gene flow among populations. We investigated the within and between field movement of Diabrotica barberi Smith and Lawrence and D. virgifera virgifera LeConte (Coleoptera: Chrysomelidae)...

  3. Spectroscopy of olivine basalts using FieldSpec and ASTER data: A case study from Wadi Natash volcanic field, south Eastern Desert, Egypt

    NASA Astrophysics Data System (ADS)

    Madani, Ahmed

    2015-10-01

    This paper aims at revealing the spectral characteristics of the olivine basalts exposed at Wadi Natash area, Egypt, using FieldSpec spectroradiometer. It also evaluates band ratios and fusion techniques for mapping purposes using ASTER data. Several volcanic episodes occurred during Early- to Late-Cretaceous are recorded in the study area. Early-Cretaceous olivine basalts are highly carbonated. Late-Cretaceous eruptions took place throughout several volcanic cones aligned in NW direction. Based on FieldSpec measurements and petrographic data, two groups of olivine basalt namely `A' and `B' are recognized. Fresh olivine basalt (group A) is characterized by low flat spectral profile with overall low reflectance values (˜20%). Spectral profile of altered olivine basalt (group B) shows moderate reflectance values (˜37%) with four little absorption features around the 1.10, 1.40, 2.00 and 2.35 μm wavelength regions. These absorption features are attributed mainly to the presence of chlorite and carbonate alteration products as indicated by petrographic examination. ASTER false colour composite band ratio image (3/2:R, 8/1:G and 8/5:B) discriminates easily the fresh and altered basalts by deep blue and reddish blue colours respectively. Image fusion between previously mentioned FCC ratios image and high spatial resolution ASTER panchromatic image are carried out using brovey and HSV transformation methods. Visual and statistical assessment methods proved that HSV fusion image yields better image interpretability results compared to brovey image. It improves the spatial resolution of original FCC ratios image with acceptable spectral preservation. The present study proved the usefulness of FieldSpec spectral profiles and the processed ASTER data for discriminating different olivine basalt groups exposed at the study area.

  4. An integrated study of the Grayburg/San Andres reservoir, Foster and South Cowden fields, Ector County, Texas, Class II

    SciTech Connect

    Trentham, DGS, Robert C.; Robinson, M.S., William C.; Wider, Kevin; Weinbrandt, Ph.D.,PE, Richard

    2000-04-14

    A project to recover economic amounts of oil from a very mature oil field is being conducted by Laguna Petroleum Corporation of Midland, Texas, with partial funding from a U. S. Department of Energy (DOE) grant to study shallow carbonate rock reservoirs. The objectives of the project are to use modern engineering methods to optimize oil field management and to use geological and geophysical data to recover untapped potential within the petroleum reservoirs. The integration of data and techniques from these disciplines has yielded results greater than those achievable without their cooperation. The cost of successfully accomplishing these goals is to be low enough for even small independent operators to afford. This article is a report describing accomplishments for the fiscal year 1998-1999.

  5. Data Analysis and Synthesis for the ONR Undersea Sand Dunes in the South China Sea Field Experiments

    DTIC Science & Technology

    2015-09-30

    in the nonlinear internal waves and tides as they shoal • Work with the acoustics team to determine how the large bedforms and wave-induced sound ...speed fluctuations impact sound propagation and loss in the vicinity of the dune field • Attempt to ascertain the mechanism of dune formation and...internal wave experiments. More specifically: • A ten-element moored array was deployed supporting both acoustic ( sound sources and hydrophones) and

  6. Giant fields of the late 80s associated with type [open quotes]A[close quotes] subduction in South America

    SciTech Connect

    Duval, B.; Cramez, C. ); Figuera, J. ); Lander, R. ); Hernandez, G. )

    1993-02-01

    About 10 billion bbl of recoverable oil have been found in these three fields for which the petroleum generating subsystem is very similar. The potential source rocks are the organic sediments associated with the major downlap surface of the post-Pangea continental encroachment sedimentary cycle, i.e., MFS 91, 5 Ma (La Luna formation). However, the concentrating physico-chemical petroleum subsystem is quite different. The El Furrial/Musipan field is associated with a Tertiary foredeep basin overlying a generating Atlantic type passive margin. On the other hand, Cusiana and Ceuta fields are associated with a Tertiary foredeep basin developed over a generating back-arc basin. The different stacking of sedimentary basins controls the migration/entrapment petroleum subsystem. In El Furrial/Musipan, decollement surfaces and their associated thrusts are predominant whereas, in Ceuta and Cusiana the majority of compressional structures are created by tectonic inversions. These tectonic settings create different petroleum systems: (a) supercharged with low impedance and lateral drainage in El Furrial/Musipan, (b) normally charged with high impedance and vertically drained in Ceuta and Cusiana area. Each case requires appropriated exploration approaches.

  7. Field collection and genetic classification of tick-borne Rickettsiae and Rickettsiae-like pathogens from South Texas: Coxiella burnetii isolated from field-collected Amblyomma cajennense.

    PubMed

    Sanders, David M; Parker, Jill E; Walker, Wes W; Buchholz, Matt W; Blount, Keith; Kiel, Johnathan L

    2008-12-01

    We are reporting the first known isolation of the Q-fever agent Coxiella burnetii from field-collected cayenne ticks Amblyomma cajennense in North America. Q-fever affects a number of domestic ungulates where it can lead to abortion in sheep and goats. There is far less known about the disease's effects on wild species, primarily because of the tendency of the disease to self resolve and to provide long-term immunity to subsequent infections. The first recovery of C. burnetii in North America was from the tick species Dermacentor andersoni. Since the original isolation C. burnetii has been recovered from five other North American tick species. The currently accepted mode for the majority of human infections is inhalation. The Centers for Disease Control and Prevention, Division of Viral and Rickettsial Diseases, Rickettsial Zoonoses Branch asserts the Q-fever agent as requiring as few as one organism to cause disease via inhalation in susceptible humans. However, with more and more isolations from ticks, evidence linking C. burnetii and ticks is mounting. The true role of tick species as competent vectors is still unconfirmed. Preemptive field collections of possible vector arthropods, hosts, and reservoirs can provide invaluable baseline environmental data that will prove supportive in follow-up studies and abatement efforts.

  8. CO2 geological storage into a lateral aquifer of an offshore gas field in the South China Sea: storage safety and project design

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Li, Dexiang; Ezekiel, Justin; Zhang, Weidong; Mi, Honggang; Ren, Shaoran

    2015-06-01

    The DF1-1 gas field, located in the western South China Sea, contains a high concentration of CO2, thus there is great concern about the need to reduce the CO2 emissions. Many options have been considered in recent years to dispose of the CO2 separated from the natural gas stream on the Hainan Island. In this study, the feasibility of CO2 storage in the lateral saline aquifer of the DF1-1 gas field is assessed, including aquifer selection and geological assessment, CO2 migration and storage safety, project design, and economic analysis. Six offshore aquifers have been investigated for CO2 geological storage. The lateral aquifer of the DF1-1 gas field has been selected as the best target for CO2 injection and storage because of its proven sealing ability, and the large storage capacity of the combined aquifer and hydrocarbon reservoir geological structure. The separated CO2 will be dehydrated on the Hainan Island and transported by a long-distance subsea pipeline in supercritical or liquid state to the central platform of the DF1-1 gas field for pressure adjustment. The CO2 will then be injected into the lateral aquifer via a subsea well-head through a horizontal well. Reservoir simulations suggest that the injected CO2 will migrate slowly upwards in the aquifer without disturbing the natural gas production. The scoping economic analysis shows that the unit storage cost of the project is approximately US26-31/ton CO2 with the subsea pipeline as the main contributor to capital expenditure (CAPEX), and the dehydration system as the main factor of operating expenditure (OPEX).

  9. The influence of tillage on field scale water fluxes and maize yields in semi-arid environments: A case study of Potshini catchment, South Africa

    NASA Astrophysics Data System (ADS)

    Kosgei, J. R.; Jewitt, G. P. W.; Kongo, V. M.; Lorentz, S. A.

    Water is a limiting resource to crop production in arid and semi-arid lands (ASALs) and is responsible for substantial yield losses annually. These lands are often occupied by resource poor smallholder rainfed farmers who have little capacity to establish conventional irrigation infrastructure to mitigate recurrent droughts and dry spells. In situ water harvesting techniques in the form of conservation agriculture practices have been identified and promoted as measures that can improve soil water availability and thus enhance crop yields. Land use practices e.g. tillage influences mechanisms of lateral flow, infiltration, storage, redistribution and residence times of water at field scale. Such alterations in flow paths have not been adequately studied in ASALs where small perturbations at field scale upstream of a catchment may have significant effects downstream. Quantifying these fluxes enables better understanding of productive and non-productive water transition processes and thus to evaluate cropping and management systems. On this study the effects of tillage on water fluxes, soil physical properties and maize ( Zea mays L.) yields were examined at three sites in the Potshini catchment, South Africa. Measurements were made on plots under no-till ( NT) and conventional till ( CT) practices. Seasonal analysis indicated that nearly twice as much runoff was generated from CT treatments when compared to NT plots. However, this was not the case at the beginning of the season. The moisture content in the root zone was significantly higher in NT treatments. Maize yield was also higher in NT compared to CT plots.

  10. South-to-North, Cross-Disciplinary Training in Global Health Practice: Ten Years of Lessons Learned from an Infectious Disease Field Course in Jamaica

    PubMed Central

    Scarlett, Henroy P.; Nisbett, Richard A.; Stoler, Justin; Bain, Brendan C.; Bhatta, Madhav P.; Castle, Trevor; Harbertson, Judith; Brodine, Stephanie K.; Vermund, Sten H.

    2011-01-01

    Global commerce, travel, and emerging and resurging infectious diseases have increased awareness of global health threats and opportunities for collaborative and service learning. We review course materials, knowledge archives, data management archives, and student evaluations for the first 10 years of an intensive summer field course in infectious disease epidemiology and surveillance offered in Jamaica. We have trained 300 students from 28 countries through collaboration between the University of the West Indies and U.S. partner universities. Participants were primarily graduate students in public health, but also included health professionals with terminal degrees, and public health nurses and inspectors. Strong institutional synergies, committed faculty, an emphasis on scientific and cultural competencies, and use of team-based field research projects culminate in a unique training environment that provides participants with career-developing experiences. We share lessons learned over the past decade, and conclude that South-to-North leadership is critical in shaping transdisciplinary, cross-cultural, global health practice. PMID:21896794

  11. THE FIRST PUBLIC RELEASE OF SOUTH POLE TELESCOPE DATA: MAPS OF A 95 deg{sup 2} FIELD FROM 2008 OBSERVATIONS

    SciTech Connect

    Schaffer, K. K.; Crawford, T. M.; Benson, B. A.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crites, A. T.; Hoover, S.; Keisler, R.; Aird, K. A.; Hrubes, J. D.; Cho, H. M.; De Haan, T.; Dobbs, M. A.; Holder, G. P.; George, E. M.; Holzapfel, W. L.; Halverson, N. W.; Joy, M.; Knox, L.; and others

    2011-12-10

    The South Pole Telescope (SPT) has nearly completed a 2500 deg{sup 2} survey of the southern sky in three frequency bands. Here, we present the first public release of SPT maps and associated data products. We present arcminute-resolution maps at 150 GHz and 220 GHz of an approximately 95 deg{sup 2} field centered at R.A. 82.{sup 0}7, decl. -55 Degree-Sign . The field was observed to a depth of approximately 17 {mu}K arcmin at 150 GHz and 41 {mu}K arcmin at 220 GHz during the 2008 austral winter season. Two variations on map filtering and map projection are presented, one tailored for producing catalogs of galaxy clusters detected through their Sunyaev-Zel'dovich effect signature and one tailored for producing catalogs of emissive sources. We describe the data processing pipeline, and we present instrument response functions, filter transfer functions, and map noise properties. All data products described in this paper are available for download at http://pole.uchicago.edu/public/data/maps/ra5h30dec-55 and from the NASA Legacy Archive for Microwave Background Data Analysis server. This is the first step in the eventual release of data from the full 2500 deg{sup 2} SPT survey.

  12. Monitoring the geothermal fluid using time lapse electrical resistivity tomography: The Pisciarelli fumarolic field test site (Campi Flegrei, South Italy)

    NASA Astrophysics Data System (ADS)

    Fedele, Alessandro; Giulia Di Giuseppe, Maria; Troiano, Antonio; Somma, Reanto; Caputo, Teresa; Patella, Domenico; Troise, Claudia; De Natale, Giuseppe

    2015-04-01

    Pisciarelli area is a fumarolic field subject to very short time morphological changes. A number of critical problems affect this area, i.e. increase of temperature of the fumaroles above the average background temperature, local seismicity and occurrence of fumaroles mixed with jets of boiling water. The presence of a very shallow aquifer seem to have the control on the behavior and composition of the fumaroles. This fumarolic field is still largely unknown regarding geophysical surveys mainly because of its limited space, surrounded on the eastern side by intense urbanization inside the large Agnano crater (Troiano et al. 2014). Currently is mainly affected by geochemical, thermal and seismic monitoring which may not fully explain the behaviour of fluids surface. Many monitoring or time lapse (TL) applications are discussed in literature (e.g., White, 1994; Daily et al., 1995; Barker and Moore, 1998; Ramirez and Daily, 2001; Carter, 2002; Slater et al., 2002; Singha and Gorelick, 2005; Cassiani et al., 2006; Swarzenski et al., 2006; de Franco et al., 2009). However all these experiments are devoted to the use of the ERT for tracer tests or in contaminant hydrology and are characterized by a short monitoring period due to the complexity and problems of long-time instrument maintenance. We propose and present a first approach of a geophysical monitoring by time lapse electrical resistivity in a fumarolic field. The profiles were acquired in January 2013, in January, March, May, July, September and November 2014 respectively. They cross the Pisciarelli area following approximately the NS direction and were characterized by a 2.5 m electrode spacing and maximum penetration depth of about 20 m. and will supply fundamental evidences on the possible seasonal resistivity fluctuations or if the resistivity changes are indicative of an increase in volcanic gases present in the hydrothermal system.

  13. Reconstructing 2000 years of hydrological variation derived from laminated proglacial sediments of Lago del Desierto at the eastern margin of the South Patagonian Ice Field, Argentina

    NASA Astrophysics Data System (ADS)

    Kastner, Stephanie; Enters, Dirk; Ohlendorf, Christian; Haberzettl, Torsten; Kuhn, Gerhard; Lücke, Andreas; Mayr, Christoph; Reyss, Jean-Louis; Wastegård, Stefan; Zolitschka, Bernd

    2010-06-01

    Lago del Desierto (49°02'S, 72°51'W) is situated in the climatically sensitive area of Southern Patagonia close to the Hielo Patagonico Sur (HPS or South Patagonian Ice Field, Argentina). Next to marine records and Antarctic ice cores, this continental area is important to reveal hemispheric and global climate trends. As instrumental climate records from this region are generally short and scarce, environmental archives are the only source of long-term records of climate variations. In this study, the potential of laminated proglacial sediments from Lago del Desierto as a palaeoclimate archive is evaluated. Two parallel gravity cores (max. length 283 cm) were analysed using a multi-proxy approach. Radiometric dating ( 14C, 210Pb and 137Cs) and tephrochronology document that the sediment cover the last 2000 years. Especially in the middle part of the record, numerous turbidites make climate variations difficult to decipher. However, after exclusion of event layers changes in sedimentological, mineralogical, and geochemical parameters reveal a long-term trend of runoff variations and sediment accessibility controlled by changes in temperature and precipitation. An abrupt transition in sediment composition occurred around AD 850 and is interpreted as a change in sediment availability related to the initial exposure of formerly glaciated areas in the catchment. This striking change mirrors the onset of warmer climate conditions during the Medieval Climate Anomaly. Moreover, the Little Ice Age cooling and the subsequent 20th century warming can be traced in the sediment record corresponding to an overall trend observed for southern South America. The proglacial lacustrine sediment record of Lago del Desierto thus constitutes a link between glacier studies of the HPS and other terrestrial climate archives in a region were long, and continuous climate records are still rare.

  14. Field-testing of guidance on the appropriate labelling of processed complementary foods for infants and young children in South Africa.

    PubMed

    Sweet, Lara; Jerling, Johann; Van Graan, Averalda

    2013-01-01

    There is a lack of formal guidance from international normative bodies on the appropriate marketing of processed complementary foods. Such guidance is necessary to protect and promote optimal infant and young child feeding practices. The aim of this study was to field-test, in South Africa, the interim guidance provided by the Maternal, Infant and Young Child Nutrition Working Group's Draft Guide for Marketing Complementary Foods as a potential tool for use by manufacturers and national governments for guiding the appropriate labelling (as a subset of appropriate marketing practices) of complementary foods. This guidance was used to develop a checklist of questions and criteria for each possible answer, which was tested using a comprehensive database of labels from products purchased in South Africa from June to August 2011. One hundred and sixty product labels of 35 manufacturers were analysed, none of which complied with all checklist criteria. Fifty-six (35%) labels did not provide an appropriate age of introduction while 37 (23%) used images of infants appearing younger than 6 months. Nineteen (12%) labels suggested a daily ration too large for a breastfed child, and 32 (20%) potentially promote the manufacturer's infant formula. Only 58 (36%) labels were easy to read. The majority (69% and 92%) of labels provided instructions for safe and appropriate preparation/use and storage, respectively. The Draft Guide for Marketing Complementary Foods was found to be a useful tool for guiding the appropriate labelling of complementary foods, although some changes and additions are recommended to improve understanding, ease of use and to minimise the subjective interpretation of the guidance.

  15. Maps showing coal-split boundaries, isopachs of coal splits, coal resources, and coal quality; Mammoth coal bed, Paleocene Tongue River Member of the Fort Union Formation, Bull Mountain coal field, south-central Montana

    SciTech Connect

    Connor, C.W.

    1989-01-01

    A U.S. Geological Survey Maps are presented showing coal-split boundaries, isopachs of coal splits, coal resources, and coal quality; mammoth coal bed, Paleocene Tongue River Member of the Fort Union Formation, Bull Mountain coal field, south-central Montana.

  16. Special Education in South Korea: Daegu University

    ERIC Educational Resources Information Center

    Kim, Byung Ha; Rhee, Kun Yong; Burns, Carol; Lerner, Janet W.

    2009-01-01

    Daegu University has enjoyed a long and remarkable history of special education. Daegu University is large University located in Daegu, South Korea, a large city in South Korea that is south of Seoul. Since the 1970's, South Korea has achieved unusual and comprehensive growth in its economy, and the field of special education continued to thrive…

  17. Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey -- GOODS-South Field, Non-SNe-Searched Visits

    NASA Astrophysics Data System (ADS)

    Faber, Sandra

    2011-10-01

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey {CANDELS}is designed to document the ?rst third of galactic evolution from z =8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IRand ACS. It will also find the first Type Ia SNe beyond z > 1.5 andestablish their accuracy as standard candles for cosmology. Fivepremier multi-wavelength sky regions selected from the SpitzerExtragalactic Deep Survey {SEDS} provide complementary IRAC imagingdata down to 26.5 AB mag, a unique resource for stellar masses at allredshifts. The use of ?ve widely separated ?elds mitigates cosmicvariance and yields statistically robust and complete samples ofgalaxies down to 10^9 solar masses out to z 8.The program merges two originally separate MCT proposals. The Faberprogram incorporates a ?Wide? imaging survey in three separate fieldsto 2 orbit depth over 0.2 sq. degrees, plus a ?Deep? imaging surveyto 12 orbit depth in the two GOODS regions over 0.04 sq. degrees.When combined with ultra-deep imaging from the Hubble Ultradeep Fieldprogram {GO 11563}, the result is a three-tiered strategy that ef?cientlysamples both bright/rare and faint/common extragalactic objects. TheFerguson program adds an extensive high-redshift Type Ia SNe search,plus ultraviolet "daytime" UVIS exposures in GOODS-N to exploit theCVZ opportunity in that field.This program, GO 12064, is part of the Wide mosaic survey, which has thefollowing field centers and sizes: Field ID RA{2000} Dec{2000} WFC3 Dim. PA on sky UDS 02 17 38 -05 12 02 4x11 270 COSMOS 10 00 31 +02 24 00 4x11 180 EGS 14 19 31 +52 54 10 3x15 41 Science highlights from the Wide program: * Underlying structural properties of galaxies as revealed by WFC3-IR images sensitive to older stars {beyond the 4000-A break} and less affected by dust than ACS. A key redshift is z 2, where star-formation peaks, QSOs are most abundant, and where restframe B-band is still accessible to WFC3. Sample questions include: - Structure in young vs. old

  18. San Juan sag: A newly discovered basin beneath San Juan volcanic field of south-central Colorado

    SciTech Connect

    Gries, R.R.

    1989-09-01

    The San Juan sag is a Laramide foreland basin formerly adjacent to and west of the Laramide northern Sangre de Cristo/San Luis highland. Wrench faulting (Eocene ) and rifting (Oligocene and Miocene) split this bounding uplift and formed the San Luis basin adjacent to and east of the sag. Volcanism concealed the San Juan sag with over 10,000 ft of intermediate volcanic deposits, and its presence remained in doubt until oil in the volcanic rocks encouraged exploration for the underlying sedimentary rocks. Drilling through the volcanic field since 1984 has revealed the presence of Paleocene and Eocene( ) clastic sediments, the Cretaceous Lewis, Mancos, and Dakota formations, and the Jurassic Morrison and Junction Creek formations. Additionally, oil and gas shows abound, and minor production has been established. Exploratory drilling and geophysical acquisitions have helped to define basin geometry, reservoir rocks, source rocks, and maturation and burial history.

  19. Spatial analysis of an intra-plate basaltic volcanic field in a compressional tectonic setting: South-eastern Australia

    NASA Astrophysics Data System (ADS)

    van den Hove, Jackson; Grose, Lachlan; Betts, Peter G.; Ailleres, Laurent; Van Otterloo, Jozua; Cas, Ray A. F.

    2017-04-01

    The Newer Volcanics Province (NVP) is a Pliocene to Recent intra-plate basaltic volcanic field (BVF) that has formed in a compressive tectonic setting (σv < σhmin < σHmax) and is not readily attributed to a single geodynamic process. A comprehensive spatial analysis of both monogenetic eruption centres and coeval vents of the NVP constrain factors that control the distribution and emplacement of volcanoes. A point-set of 434 eruption centres totalling 726 vents are divided into three geographical sub-provinces for analysis. Kernel density estimation and Poisson nearest neighbour analysis are used to scrutinize the distribution of eruption centres. A simple and novel fitted regression line method is used to determine the orientation of coeval vents, and Hough transform and two-point azimuth methods are used to identify alignments and alignment trends between eruption centres. The distribution of eruption centres and their relative spatial density corresponds with the extent of thinner lithosphere. Eruption centres of the NVP have a clustered distribution whilst smaller sub-sets of eruption centres are distributed more uniformly. The main alignment trends between coeval vents related to individual dikes and between eruption centres related to successive temporally discrete dikes are primarily oriented nearly parallel with pre-existing crustal fault trends. The frequency of volcanic alignments shows faults oriented nearly parallel to the orientation of the regional maximum horizontal compressive stress (σ1) are favourably utilised by intrusions over other fault trends. The depth from which pre-existing faults facilitate dike propagation is not constrained. We interpret they are likely important in preventing dikes from stalling and forming sills under a compressive stress field in the case of the NVP. It is also observed that coeval vent alignments are more strongly aligned in areas overlying consolidated basement relative to areas of poorly consolidated basin

  20. An integrated study of the Grayburg/San Andres Reservoir, Foster and South Cowden Fields, Ector County, Texas. Annual report, August 1, 1996--July 31, 1997

    SciTech Connect

    Trentham, R.C.; Weinbrandt, R.; Robinson, W.

    1997-12-01

    The objective of this two-phase study is to demonstrate an integrated methodology for reservoir characterization of shallow shelf carbonate reservoir that is feasible, and cost effective for the independent operator. Furthermore, it will provide one of the first public demonstrations of the enhancement of reservoir characterization using high-resolution three dimensional (3D) seismic data. This particular project is evaluating the Grayburg and San Andres reservoirs in the Foster and South Cowden Fields, Ector County, Texas. This 68 year old field was approaching its economic limit and the leases evaluated would have been abandoned in 10 years. A multidisciplinary approach to waterflood design and implementation, along with the addition of reserves by selective infill drilling and deepening, is being applied to this field. This approach in reservoir development will be applicable to a wide range of shallow shelf carbonate reservoirs throughout the US. The first phase of the project included the design, acquisition, and interpretation of the 3D seismic survey, the collection and evaluation of geologic (core and log) data, and engineering (historical production, well test, injection) data from a variety of sources. From this work, a geologically based production history model was simulated. Based on the recommendations made at the end of Phase One, three new wells were drilled, one existing well was deepened, two wells were worked over, one TA`d well was re-entered, and one well was converted to injection. In addition, the quality of the injection water was greatly improved, a step necessary prior to increasing injection in the project area. The realignment of the waterflood and all additional well work await the completion of the seismic based history match and engineering simulation.

  1. A diagnosis of sub-surface water table dynamics in low hydraulic conductivity soils in the sugar cane fields of Pongola, South Africa

    NASA Astrophysics Data System (ADS)

    Malota, Mphatso; Senzanje, Aidan

    2016-04-01

    Water and land are the two natural resources restraining crop production in South Africa. With the increasing demand for food, emphasis has shifted from the sole reliance on rain fed crop production, to irrigation. The deterioration in irrigation water quality from surface water sources is, however, posing a big challenge to the sustainability of irrigated crop production. This is because more water is required for leaching, resulting in shallow water tables in agricultural lands. The installation of well designed subsurface drainage systems alone is not enough; the provision of timely maintenance is also necessary. In this study, the extent and severity of problems as a consequence of shallow water tables and their possible causes were investigated at three sugarcane fields in Pongola, South Africa, having low hydraulic conductivity soils. Also investigated were soil salinity levels and the temporal variation in the salinity of the irrigation water. A water table map of a 32 ha sugarcane field was generated, using observed water table depth (WTD) data from 36 piezometers monitored from September 2011 to February 2012. Out of the total 32 ha under cultivation, 12% was found to be affected by shallow WTDs of less than the 1.0 m design WTD. The inability of natural drainage to cope with subsurface drainage needs and the poor maintenance of subsurface drainage systems contributed to the shallow water tables in the area. Furthermore, the currently adopted drainage design criteria also proved unsatisfactory with mean observed water table depth and drainage discharge (DD) of 20% and 50%, respectively, less than their respective design levels. The salinity of the irrigation water was, on average, 32% higher than threshold tolerance level of sugarcane. The root zone soil salinity levels at the three study sites were greater than the 1.7 dS m-1 threshold for sugar cane. The subsurface drainage design criteria adopted at the site needs to be revisited by ensuring that the

  2. Modeling Hurricane Katrina's merchantable timber and wood damage in south Mississippi using remotely sensed and field-measured data

    NASA Astrophysics Data System (ADS)

    Collins, Curtis Andrew

    Ordinary and weighted least squares multiple linear regression techniques were used to derive 720 models predicting Katrina-induced storm damage in cubic foot volume (outside bark) and green weight tons (outside bark). The large number of models was dictated by the use of three damage classes, three product types, and four forest type model strata. These 36 models were then fit and reported across 10 variable sets and variable set combinations for volume and ton units. Along with large model counts, potential independent variables were created using power transforms and interactions. The basis of these variables was field measured plot data, satellite (Landsat TM and ETM+) imagery, and NOAA HWIND wind data variable types. As part of the modeling process, lone variable types as well as two-type and three-type combinations were examined. By deriving models with these varying inputs, model utility is flexible as all independent variable data are not needed in future applications. The large number of potential variables led to the use of forward, sequential, and exhaustive independent variable selection techniques. After variable selection, weighted least squares techniques were often employed using weights of one over the square root of the pre-storm volume or weight of interest. This was generally successful in improving residual variance homogeneity. Finished model fits, as represented by coefficient of determination (R2), surpassed 0.5 in numerous models with values over 0.6 noted in a few cases. Given these models, an analyst is provided with a toolset to aid in risk assessment and disaster recovery should Katrina-like weather events reoccur.

  3. A multi-wavelength study of z = 3.15 Lyman-α emitters in the GOODS South Field

    NASA Astrophysics Data System (ADS)

    Nilsson, K. K.; Møller, P.; Möller, O.; Fynbo, J. P. U.; Michałowski, M. J.; Watson, D.; Ledoux, C.; Rosati, P.; Pedersen, K.; Grove, L. F.

    2007-08-01

    Context: Lyα-emitters have proven to be excellent probes of faint, star-forming galaxies in the high redshift universe. However, although the sample of known emitters is increasingly growing, their nature (e.g. stellar masses, ages, metallicities, star-formation rates) is still poorly constrained. Aims: We aim to study the nature of Lyα-emitters, to find the properties of a typical Lyα-emitting galaxy and to compare these properties with the properties of other galaxies at similar redshift, in particular Lyman-break galaxies. Methods: We have performed narrow-band imaging at the VLT, focused on Lyα at redshift z ≈ 3.15, in the GOODS-S field. We have identified a sample of Lyα-emitting candidates, and we have studied their Spectral Energy Distributions (SEDs). Results: We find that the emitters are best fit by an SED with low metallicity (Z/Z⊙ = 0.005), low dust extinction (AV ≈ 0.26) and medium stellar masses of approximately 109 M⊙. The age is not very well constrained. One object out of 24 appears to be a high redshift Lyα-emitting dusty starburst galaxy. We find filamentary structure as traced by the Lyα-emitters at the 4σ level. The rest-frame UV SED of these galaxies is very similar to that of Lyman Break Galaxies (LBGs) and comply with the selection criteria for U-band drop-outs, except they are intrinsically fainter than the current limit for LBGs. Conclusions: Lyα-emitters are excellent probes of galaxies in the distant universe, and represent a class of star-forming, dust and AGN free, medium mass objects. Based on observations carried out at the European Southern Observatory (ESO) under prog. ID No. 70.A-0447, 274.A-5029 and LP168.A-0485.

  4. Field guide to the Mesozoic accretionary complex along Turnagain Arm and Kachemak Bay, south-central Alaska

    USGS Publications Warehouse

    Bradley, Dwight C.; Kusky, Timothy M.; Karl, Susan M.; Haeussler, Peter J.

    1997-01-01

    Turnagain Arm, just east of Anchorage, provides a readily accessible, world-class cross section through a Mesozoic accretionary wedge. Nearly continuous exposures along the Seward Highway, the Alaska Railroad, and the shoreline of Turnagain Arm display the two main constituent units of the Chugach terrane: the McHugh Complex and Valdez Group. In this paper we describe seven bedrock geology stops along Turnagain Arm, and two others in the Chugach Mountains just to the north (Stops 1-7 and 9), which will be visited as part of the May, 1997 field trip of the Alaska Geological Society. Outcrops along Turnagain Arm have already been described in two excellent guidebook articles (Clark, 1981; Winkler and others 1984), both of which remain as useful and valid today as when first published. Since the early 1980's, studies along Turnagain Arm have addressed radiolarian ages of chert and conodont ages of limestone in the McHugh Complex (Nelson and others, 1986, 1987); geochemistry of basalt in the McHugh Complex (Nelson and Blome, 1991); post-accretion brittle faulting (Bradley and Kusky, 1990; Kusky and others, 1997); and the age and tectonic setting of gold mineralization (Haeussler and others, 1995). Highlights of these newer findings will described both in the text below, and in the stop descriptions.Superb exposures along the southeastern shore of Kachemak Bay show several other features of the McHugh Complex that are either absent or less convincing along Turnagain Arm. While none of these outcrops can be reached via the main road network, they are still reasonably accessible - all are within an hour by motorboat from Homer, seas permitting. Here, we describe seven outcrops along the shore of Kachemak Bay that we studied between 1989 and 1993 during geologic mapping of the Seldovia 1:250,000- scale quadrangle. These outcrops (Stops 61-67) will not be part of the 1997 itinerary, but are included here tor the benefit of those who may wish to visit them later.

  5. Hoarding decisions by Edward's long-tailed rats (Leopoldamys edwardsi) and South China field mice (Apodemus draco): the responses to seed size and germination schedule in acorns.

    PubMed

    Chang, Gang; Xiao, Zhishu; Zhang, Zhibin

    2009-09-01

    Co-varying traits in acorns such as seed size and germination schedule are important to influence the behavioural decisions of hoarding rodents. Using acorn pairs from cork oak (Quercus variabilis) (large size and short germination schedules) serrate oak (Q. serrata) (small size and short germination schedule) and qinggang (Cyclobalanopsis glauca) (small size and long germination schedule) with contrasting seed size and germination schedule, we conducted a series of experiments to investigate hoarding preferences in response to seed size and germination schedule by Edward's long-tailed rats (Leopoldamys edwardsi) and South China field mice (Apodemus draco) in semi-natural enclosures. We found that the seed size hypothesis was consistently supported: both rodent species ate more small acorns but hoarded more large ones regardless of germination schedules. However, the germination schedule hypothesis was also supported when similar sized acorns were simultaneously provided, e.g. Q. serrata versus C. glauca or germinating versus non-germinating Q. variabilis. Our results, contrary to the studies from North America, indicate that seed size is more important than germination schedules in determining whether the tested animals eat or hoard a given seed.

  6. Statistical characteristics of nighttime mid-latitude F-region field-aligned irregularities observed by Daejeon VHF coherent scattering radar in South Korea

    NASA Astrophysics Data System (ADS)

    Yang, T. Y.; Kwak, Y. S.; Kil, H.; Lee, Y.; Lee, W. K.; Park, Y. D.

    2014-12-01

    We report statistical characteristics of mid-latitude nighttime F-region field-aligned irregularities (FAIs) based on more than three-year observations by Daejeon VHF coherent backscatter radar. This radar has built at Daejeon (36.18°N, 127.14°E, dip lat. 26.7°N) in 2009 with 40.8 MHz operating frequency for continuous monitoring of the behavior of electron density irregularities in the middle latitude. By using long-term observations from January 2010 to December 2013, we obtained the annual, diurnal and seasonal characteristics of a variety of a percentage occurrence, signal-to-noise ratio, and Doppler velocities from the nighttime F-region irregularities over Korea peninsular. From almost four-year observations, the F-region nighttime irregularities occurred most frequently during post-sunset period. These nighttime irregularities usually appeared with occupying different height levels according to local time. This height variation of F-region FAIs was correlated with hmf2 of ionosonde in Icheon, South Korea. The irregularities were least active near the winter solstice and most active near summer solstice. From the annual occurrence variations, F-region nighttime irregularities seem to have tendency with solar activity.

  7. Simple Techniques For Assessing Impacts Of Oil And Gas Operations On Federal Lands - A Field Evaluation At Big South Fork National River And Recreation Area, Scott County, Tennessee

    USGS Publications Warehouse

    Otton, James K.; Zielinski, Robert A.

    2000-01-01

    Simple, cost-effective techniques are needed for land managers to assess the environmental impacts of oil and gas production activities on public lands so that sites may be prioritized for further, more formal assessment or remediation. These techniques should allow the field investigator to extend the assessment beyond the surface disturbances documented by simple observation and mapping using field-portable instruments and expendable materials that provide real-time data. The principal contaminants of current concern are hydrocarbons, produced water, and naturally occurring radioactive materials (NORM). Field investigators can examine sites for the impacts of hydrocarbon releases using a photoionization detector (PID) and a soil auger. Volatile organic carbon (VOC) in soil gases in an open auger hole or in the head space of a bagged and gently warmed auger soil sample can be measured by the PID. This allows detection of hydrocarbon movement in the shallow subsurface away from areas of obvious oil-stained soils or oil in pits at a production site. Similarly, a field conductivity meter and chloride titration strips can be used to measure salts in water and soil samples at distances well beyond areas of surface salt scarring. Use of a soil auger allows detection of saline subsoils in areas where salts may be flushed from the surface soil layers. Finally, a microRmeter detects the presence of naturally occurring radioactive materials (NORM) in equipment and soils. NORM often goes undetected at many sites although regulations limiting NORM in equipment and soils are being promulgated in several States and are being considered by the USEPA. With each technique, background sampling should be done for comparison with impacted areas. The authors examined sites in the Big South Fork National River and Recreation Area in November of 1999. A pit at one site at the edge of the flood plain of a small stream had received crude oil releases from a nearby tank. Auger holes down

  8. SUDARE-VOICE variability-selection of active galaxies in the Chandra Deep Field South and the SERVS/SWIRE region

    NASA Astrophysics Data System (ADS)

    Falocco, S.; Paolillo, M.; Covone, G.; De Cicco, D.; Longo, G.; Grado, A.; Limatola, L.; Vaccari, M.; Botticella, M. T.; Pignata, G.; Cappellaro, E.; Trevese, D.; Vagnetti, F.; Salvato, M.; Radovich, M.; Hsu, L.; Capaccioli, M.; Napolitano, N.; Brandt, W. N.; Baruffolo, A.; Cascone, E.; Schipani, P.

    2015-07-01

    Context. One of the most peculiar characteristics of active galactic nuclei (AGNs) is their variability over all wavelengths. This property has been used in the past to select AGN samples and is foreseen to be one of the detection techniques applied in future multi-epoch surveys, complementing photometric and spectroscopic methods. Aims: In this paper, we aim to construct and characterise an AGN sample using a multi-epoch dataset in the r band from the SUDARE-VOICE survey. Methods: Our work makes use of the VST monitoring programme of an area surrounding the Chandra Deep Field South to select variable sources. We use data spanning a six-month period over an area of 2 square degrees, to identify AGN based on their photometric variability. Results: The selected sample includes 175 AGN candidates with magnitude r< 23 mag. We distinguish different classes of variable sources through their lightcurves, as well as X-ray, spectroscopic, SED, optical, and IR information overlapping with our survey. Conclusions: We find that 12% of the sample (21/175) is represented by supernovae (SN). Of the remaining sources, 4% (6/154) are stars, while 66% (102/154) are likely AGNs based on the available diagnostics. We estimate an upper limit to the contamination of the variability selected AGN sample ≃34%, but we point out that restricting the analysis to the sources with available multi-wavelength ancillary information, the purity of our sample is close to 80% (102 AGN out of 128 non-SN sources with multi-wavelength diagnostics). Our work thus confirms the efficiency of the variability selection method, in agreement with our previous work on the COSMOS field. In addition we show that the variability approach is roughly consistent with the infrared selection.

  9. Shipboard magnetic field data trace magnetic sources in marine sediments: Geophysical studies of the Stono and North Edisto Inlets near Charleston, South Carolina

    NASA Astrophysics Data System (ADS)

    Shah, A. K.; Harris, S.

    2010-12-01

    Magnetic field data are traditionally used to analyze igneous and metamorphic rocks, but recent efforts have shown that magnetic sources within sediments may be detectable. Candidates for such sources include heavy mineral sands transported from upland sources, biogenic magnetite, and certain forms of glauconite. Magnetic field surveys can then be used to map distributions of these sediments with much denser and widespread coverage than possible by sampling, providing constraints on the deposition and transport of local sediments. However, as sedimentary sources are likely to be much weaker than their crystalline counterparts, mapping requires the sensor to be relatively close to the source, and filtering approaches are needed to distinguish signals from both system noise and deeper basement features. In July 2010, we conducted marine geophysical surveys over the Stono and North Edisto inlets and their riverine inputs south of Charleston, SC using a total field cesium magnetometer and 900 kHz sidescan sonar. In these tidally influenced estuarine environments, unconsolidated Quaternary sediments of thickness typically vary within 0-10 meters overly an indurated Tertiary substrate. Calm survey conditions allowed the towing of sensors 2-20 m above the seabed with background magnetometer variations less than 0.5 nT for a measurement spacing of less than 0.4 m. Anomalies associated with metallic objects such as crab pots or other anthropogenic debris were filtered in part by comparisons to the high-resolution sonar. Using spectral processing to highlight short-wavelength magnetic anomalies, we find that shallow areas where sidescan data indicate a sand-covered seabed are associated with 10-40 m wide, 1-6 nT magnetic anomalies. These anomalies are distinct from system noise, but are too narrow to represent basement features. The anomalies are observed mostly in shallow areas where rivers that originate from upland areas enter the inlets. In contrast, the anomalies are

  10. Trophic relationships on a fucoid shore in south-western Iceland as revealed by stable isotope analyses, laboratory experiments, field observations and gut analyses

    NASA Astrophysics Data System (ADS)

    Steinarsdóttir, M. B.; Ingólfsson, A.; Ólafsson, E.

    2009-04-01

    Rocky shores in the North Atlantic are known for their zonation patterns of both algae and animals, which can be expected to greatly affect food availability to consumers at different height levels on the shore. We tested the hypothesis that consumers would feed on the most abundant suitable food source in their surroundings. In total 36 species/taxa of common primary producers and consumers were sampled for stable isotope analyses from a sheltered fucoid shore at Hvassahraun in south-western Iceland. A selection of these species was also collected seasonally and from different height levels. Feeding experiments, field observations and gut analyses were also conducted. Our results were in good overall agreement with pre-existing knowledge of trophic relationships in the rocky intertidal. Consumers often appeared to be assimilating carbon and nitrogen from the most common diet in their immediate surroundings. The predator Nucella lapillus was thus feeding on different prey at different height levels in accordance with different densities of prey species. When tested in the laboratory, individuals taken from low on the shore would ignore the gastropod Littorina obtusata, uncommon at that height level, even when starved, while individuals from mid-shore readily ate the gastropod. This indicated that some kind of learned behaviour was involved. There were, however, important exceptions, most noteworthy the relatively small contribution to herbivores, both slow moving (the gastropod L. obtusata) and fast moving (the isopod Idotea granulosa and the amphipod Gammarus obtusatus) of the dominant alga at this site, Ascophyllum nodosum. The recent colonizer Fucus serratus seemed to be favoured. Selective feeding was indicated both by isotope signatures as well as by results of feeding experiments. Seasonal migrations of both slow and fast moving species could partly explain patterns observed.

  11. MIPS 24 {mu}m OBSERVATIONS OF THE HUBBLE DEEP FIELD SOUTH: PROBING THE IR-RADIO CORRELATION OF GALAXIES AT z>1

    SciTech Connect

    Huynh, Minh T.; Gawiser, Eric; Marchesini, Danilo; Brammer, Gabriel; Guaita, Lucia

    2010-11-10

    We present MIPS 24 {mu}m observations of the Hubble Deep Field South taken with the Spitzer Space Telescope. The resulting image is 254 arcmin{sup 2} in size and has a sensitivity ranging between {approx}12 and {approx}30 {mu}Jy rms, with a median sensitivity of {approx}20 {mu}Jy rms. A total of 495 sources have been cataloged with a signal-to-noise ratio greater than 5{sigma}. The source catalog is presented as well as source counts which have been corrected for completeness and flux boosting. The IR sources are then combined with MUSYC optical/NIR and ATHDFS radio observations to obtain redshifts and radio flux densities of the sample. We use the IR/radio flux density ratio (q{sub 24}) to explore the IR-radio correlation for this IR sample and find q{sub 24} = 0.71 {+-} 0.31 for sources detected in both IR and radio. The results are extended by stacking IR sources not detected in the radio observations and we derive an average q{sub 24} for redshift bins between 0 < z < 2.5. We find that the high-redshift (z>1) sources have an average q{sub 24} ratio which is better fit by local LIRG SEDs rather than local ULIRG SEDs, indicating that high-redshift ULIRGs differ in their IR/radio properties. So, ULIRGs at high-redshift have SEDs different from those found locally. Infrared-faint radio sources are examined, and while nine radio sources do not have an MIPS detection and are therefore radio-loud active galactic nuclei (AGNs), only one radio source has an extreme IRAC 3.6 {mu}m to radio flux density ratio indicating it is a radio-loud AGN at z>1.

  12. Differential Incorporation of Carbon Substrates among Microbial Populations Identified by Field-Based, DNA Stable-Isotope Probing in South China Sea

    PubMed Central

    Xie, Xiabing; Jiao, Nianzhi

    2016-01-01

    To determine the adapted microbial populations to variant dissolved organic carbon (DOC) sources in the marine environment and improve the understanding of the interaction between microorganisms and marine DOC pool, field-based incubation experiments were carried out using supplemental 13C-labeled typical substrates D-glucose and D-glucosamine (D-Glc and D-GlcN, respectively), which are two important components in marine DOC pool in the South China Sea. 13C- and 12C-DNA were then fractionated by ultracentrifugation and the microbial community was analyzed by terminal-restriction fragment length polymorphism and 454 pyrosequencing of 16S rRNA gene. 12C-DNA-based communities showed relatively high similarities with their corresponding in situ communities, and their bacterial diversities were generally higher than 13C-DNA-based counterparts. Distinct differences in community composition were found between 13C- and 12C-DNA-based communities and between two substrate-supplemented 13C-DNA-based communities; these differences distinctly varied with depth and site. In most cases, there were more genera with relative abundances of >0.1% in D-Glc-incorporating communities than in D-GlcN-incorporating communities. The Roseobacter clade was one of the prominent actively substrate-incorporating bacterial populations in all 13C-DNA-based communities. Vibrio was another prominent actively D-GlcN-incorporating bacterial population in most incubations. However notably, different OTUs dominated this clade or genus in different treatments at different depths. Altogether, these results suggested that there were taxa-specific differences in DOC assimilations and, moreover, their differences varied among the typical water masses, which could have been caused by the variant compositions of original bacterial communities from different hydrological environments. This implies that ecologically, the levels of labile or recalcitrance of DOC can be maintained only in a specific environmental

  13. Evaluation of the horizontal-to-vertical spectral ratio (HVSR) seismic method to determine sediment thickness in the vicinity of the south well field, Franklin county, OH

    USGS Publications Warehouse

    Haefner, R.J.; Sheets, R.A.; Andrews, R.E.

    2010-01-01

    The horizontal-to-vertical spectral ratio (HVSR) seismic method involves analyzing measurements of ambient seismic noise in three dimensions to determine the fundamental site resonance frequency. Resonance is excited by the interaction of surface waves (Rayleigh and Love) and body waves (vertically incident shear) with the high-contrast acoustic impedance boundary at the bedrock-sediment interface. Measurements were made to determine the method's utility for estimating thickness of unconsolidated glacial sediments at 18 locations at the South Well Field, Franklin County, OH, and at six locations in Pickaway County where sediment thickness was already known. Measurements also were made near a high-capacity production well (with pumping on and off ) and near a highway and a limestone quarry to examine changes in resonance frequencies over a 20-hour period. Although the regression relation for resonance frequency and sediment thickness had a relatively low r 2(0.322), estimates of sediment thickness were, on average, within 14 percent of known thicknesses. Resonance frequencies for pumping on and pumping off were identical, although the amplitude of the peak was nearly double under pumping conditions. Resonance frequency for the 20-hour period did not change, but the amplitude of the peak changed considerably, with a maximum amplitude in the early afternoon and minimum in the very early morning hours. Clay layers within unconsolidated sediments may influence resonance frequency and the resulting regression equation, resulting in underestimation of sediment thickness; however, despite this and other complicating factors, hydrogeologists should consider this method when thickness data are needed for unconsolidated sediments. ?? 2011 by The Ohio Academy of Science. All Rights Reserved.

  14. Evaluation of the horizontal-to-vertical spectral ratio (HVSR) seismic method to determine sediment thickness in the vicinity of the South Well Field, Franklin County, OH

    USGS Publications Warehouse

    Haefner, Ralph J.; Sheets, Rodney A.; Andrews, Robert E.

    2011-01-01

    The horizontal-to-vertical spectral ratio (HVSR) seismic method involves analyzing measurements of ambient seismic noise in three dimensions to determine the fundamental site resonance frequency. Resonance is excited by the interaction of surface waves (Rayleigh and Love) and body waves (vertically incident shear) with the high-contrast aconstic impedance boundary at the bedrock-sediment interface. Measurements were made to determine the method's utility for estimating thickness of unconsolidated glacial sediments at 18 locations at the South Well Field, Franklin County, OH, and at six locations in Pickaway County where sediment thickness was already known. Measurements also were made near a high-capacity production well (with pumping on and off) and near a highway and a limestone quarry to examine changes in resonance frequencies over a 20-hour period. Although the regression relation for resonance frequency and sediment thickness had a relatively low [r.sup.2] (0.322), estimates of sediment thickness were, on average, within 14 percent of known thicknesses. Resonance frequencies for pumping on and pumping off were identical, although the amplitude of the peak was nearly double under pumping conditions. Resonance frequency for the 20-hour period did not change, but the amplitude of the peak changed considerably, with a maximum amplitude in the early afternoon and minimum in the very early morning hours. Clay layers within unconsolidated sediments may influence resonance frequency and the resulting regression equation, resulting in underestimation of sediment thickness; however, despite this and other complicating factors, hydrogeologists should consider this method when thickness data are needed for unconsolidated sediments.

  15. Occurrence climatology of F region field-aligned irregularities in middle latitudes as observed by a 40.8 MHz coherent scatter radar in Daejeon, South Korea

    NASA Astrophysics Data System (ADS)

    Yang, Tae-Yong; Kwak, Young-Sil; Kil, Hyosub; Lee, Young-Sook; Lee, Woo Kyoung; Lee, Jae-jin

    2015-11-01

    A new 40.8 MHz coherent scatter radar was built in Daejeon, South Korea (36.18°N, 127.14°E, dip latitude: 26.7°N) on 29 December 2009 and has since been monitoring the occurrence of field-aligned irregularities (FAIs) in the northern middle latitudes. We report on the occurrence climatology of the F region FAIs as observed by the Daejeon radar between 2010 and 2014. The F region FAIs preferentially occur around 250-350 km at 18:00-21:00 local time (postsunset FAI), around 350-450 km near midnight (nighttime FAI), around 250-350 km before sunrise (presunrise FAI), and around 160-300 km after 05:00 local time (postsunrise FAI). The occurrence rates of nighttime and presunrise FAIs are maximal during summer, though the occurrence rates of postsunset and postsunrise FAIs are maximal during the equinoxes. FAIs rarely occur during local winter. The occurrence rate of F region FAIs increases in concert with increases in solar activity. Medium-scale traveling ionospheric disturbances (MSTIDs) are known as an important source of the F region FAIs in middle latitudes. The high occurrence rate of the nighttime FAIs in local summer is consistent with the high occurrence rate of MSTIDs in that season. However, the dependence of the FAI activity on the solar cycle is inconsistent with the MSTID activity. The source of the F region FAIs in middle latitudes is an open question. Our report of different types of FAIs and their occurrence climatology may provide a useful reference for the identification of the source of the middle latitude FAIs.

  16. An ALMA survey of submillimeter galaxies in the extended Chandra deep field south: The redshift distribution and evolution of submillimeter galaxies

    SciTech Connect

    Simpson, J. M.; Swinbank, A. M.; Smail, Ian; Alexander, D. M.; Danielson, A. L. R.; Thomson, A. P.; Brandt, W. N.; Bertoldi, F.; Karim, A.; De Breuck, C.; Chapman, S. C.; Coppin, K. E. K.; Da Cunha, E.; Hodge, J. A.; Schinnerer, E.; Dannerbauer, H.; Greve, T. R.; Ivison, R. J.; Knudsen, K. K.; Poggianti, B. M.; and others

    2014-06-20

    We present the first photometric redshift distribution for a large sample of 870 μm submillimeter galaxies (SMGs) with robust identifications based on observations with ALMA. In our analysis we consider 96 SMGs in the Extended Chandra Deep Field South, 77 of which have 4-19 band photometry. We model the SEDs for these 77 SMGs, deriving a median photometric redshift of z {sub phot} = 2.3 ± 0.1. The remaining 19 SMGs have insufficient photometry to derive photometric redshifts, but a stacking analysis of Herschel observations confirms they are not spurious. Assuming that these SMGs have an absolute H-band magnitude distribution comparable to that of a complete sample of z ∼ 1-2 SMGs, we demonstrate that they lie at slightly higher redshifts, raising the median redshift for SMGs to z {sub phot} = 2.5 ± 0.2. Critically we show that the proportion of galaxies undergoing an SMG-like phase at z ≥ 3 is at most 35% ± 5% of the total population. We derive a median stellar mass of M {sub *} = (8 ± 1) × 10{sup 10} M {sub ☉}, although there are systematic uncertainties of up to 5 × for individual sources. Assuming that the star formation activity in SMGs has a timescale of ∼100 Myr, we show that their descendants at z ∼ 0 would have a space density and M{sub H} distribution that are in good agreement with those of local ellipticals. In addition, the inferred mass-weighted ages of the local ellipticals broadly agree with the look-back times of the SMG events. Taken together, these results are consistent with a simple model that identifies SMGs as events that form most of the stars seen in the majority of luminous elliptical galaxies at the present day.

  17. The specific features of gold ore provinces of the south of Siberia in a magnetic field at ground height and heights of flight of satellite Champ.

    NASA Astrophysics Data System (ADS)

    Litvinova, Tamara; Petrova, Alevtina

    2010-05-01

    The specific features of gold ore provinces of the south of Siberia in a magnetic field at ground height and heights of flight of satellite Champ. T.Litvinova -All-Russian Geological Research Institute (VSEGEI) A. Petrova - St. Petersburg, SPbF IZMIRAN, Russian Academy of Sciences, St. Petersburg For allocation of specific features known gold ore objects (Olimpiadninskoje, Suchoi Log, etc.) is executed the morphological analysis of the magnetic field received on materials of aeromagnetic data and satellite measurements at heights of 100 and 400 km. On the ground data on a map of magnetic anomalies of Russia of scale 1:2 500000 of 50 km on the extended structures crossing known gold ore deposits and promising ore units have been constructed geomagnetic and densitys sections up to depth. On geomagnetic and densitys sections to known large gold ore to deposits are dated deep synvertical the permeable zones described by a synlenticular -layered structure. Extended horizons of not magnetic formations are located on depths about 10, 12, 15-18, 30 and 40 km. On deep densitys sections reference sites ¬ the Suchoi Log, Olimpiadninskoje and Vodorazdelnoje ¬ is characterized by zones of inversion of density. Areas of the loosened breeds are dated to synvertical to deep zones of hydrothermal and fluid study of breeds inside which the loosened lenses in intervals of depths from 2 up to 5 km are formed, 8-13 km, 18-20 and 25-30 km of 35-40 km within the limits of the bottom bark. The analysis of a magnetic field has shown, that gold mineralization in researched region is dated for zones of long-living regional explosive infringements, to permeable terrigenous to thicknesses of depressions, to adjournment depression structures in units of crossing of tectonofluid zones of diagonal orientation. Terrigenous adjournment depression structures are shown on a geomagnetic section as the powerful deflections filled with low-magnetic thicknesses. These deflections are dated to

  18. View from south/southeast at Chapel of grave area C, south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from south/southeast at Chapel of grave area C, south rond point, and grave area D. Note flagstone path and steps leading to rond point from Chapel. - Flanders Field American Cemetery & Memorial, Wortegemseweg 117, Waregem, West Flanders (Belgium)

  19. LIVING ROOM, LOOKING SOUTH TOWARD FIREPLACE AND PORCH ENTRANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LIVING ROOM, LOOKING SOUTH TOWARD FIREPLACE AND PORCH ENTRANCE - Hamilton Field, Field Officers' Quarters Type A, Sunset Drive, Las Lomas Drive, South Circle, & Casa Grande Real, Novato, Marin County, CA

  20. Ship Shoal as a prospective borrow site for barrier island restoration, coastal south-central Louisiana, Usa: Numerical wave modeling and field measurements of hydrodynamics and sediment transport

    USGS Publications Warehouse

    Stone, G.W.; Pepper, D.A.; Xu, Jie; Zhang, X.

    2004-01-01

    Ship Shoal, a transgressive sand body located at the 10 m isobath off south-central Louisiana, is deemed a potential sand source for restoration along the rapidly eroding Isles Dernieres barrier chain and possibly other sites in Louisiana. Through numerical wave modeling we evaluate the potential response of mining Ship Shoal on the wave field. During severe and strong storms, waves break seaward of the western flank of Ship Shoal. Therefore, removal of Ship Shoal (approximately 1.1 billion m3) causes a maximum increase of the significant wave height by 90%-100% and 40%-50% over the shoal and directly adjacent to the lee of the complex for two strong storm scenarios. During weak storms and fair weather conditions, waves do not break over Ship Shoal. The degree of increase in significant wave height due to shoal removal is considerably smaller, only 10%-20% on the west part of the shoal. Within the context of increasing nearshore wave energy levels, removal of the shoal is not significant enough to cause increased erosion along the Isles Dernieres. Wave approach direction exerts significant control on the wave climate leeward of Ship Shoal for stronger storms, but not weak storms or fairweather. Instrumentation deployed at the shoal allowed comparison of measured wave heights with numerically derived wave heights using STWAVE. Correlation coefficients are high in virtually all comparisons indicating the capability of the model to simulate wave behavior satisfactorily at the shoal. Directional waves, currents and sediment transport were measured during winter storms associated with frontal passages using three bottom-mounted arrays deployed on the seaward and landward sides of Ship Shoal (November, 1998-January, 1999). Episodic increases in wave height, mean and oscillatory current speed, shear velocity, and sediment transport rates, associated with recurrent cold front passages, were measured. Dissipation mechanisms included both breaking and bottom friction due to

  1. Extreme erosion response after wildfire in the Upper Ovens, south-east Australia: Assessment of catchment scale connectivity by an intensive field survey

    NASA Astrophysics Data System (ADS)

    Box, Walter; Keestra, Saskia; Nyman, Petter; Langhans, Christoph; Sheridan, Gary

    2015-04-01

    South-eastern Australia is generally regarded as one of the world's most fire-prone environments because of its high temperatures, low rainfall and flammable native Eucalyptus forests. Modifications to the landscape by fire can lead to significant changes to erosion rates and hydrological processes. Debris flows in particular have been recognised as a process which increases in frequency as a result of fire. This study used a debris flow event in the east Upper Ovens occurred on the 28th of February 2013 as a case study for analysing sediment transport processes and connectivity of sediment sources and sinks. Source areas were identified using a 15 cm resolution areal imagery and a logistic regression model was made based on fire severity, aridity index and slope to predict locations of source areas. Deposits were measured by making cross-sections using a combination of a differential GPS and a total station. In total 77 cross-sections were made in a 14.1 km2 sub-catchment and distributed based on channel gradient and width. A more detailed estimation was obtained by making more cross-sections where the volume per area is higher. Particle size distribution between sources and sink areas were obtained by combination of field assessment, photography imagery analyses and sieve and laser diffraction. Sediment was locally eroded, transported and deposited depending on factors such as longitude gradient, stream power and the composition of bed and bank material. The role of headwaters as sediment sinks changed dramatically as a result of the extreme erosion event in the wildfire affected areas. Disconnected headwaters became connected to low order streams due to debris flow processes in the contributing catchment. However this redistribution of sediment from headwaters to the drainage network was confined to upper reaches of the Ovens. Below this upper part of the catchment the event resulted in redistribution of sediment already existing in the channel through a

  2. The effect of the Gulf Stream current field on wave propagation onto South East Florida reefs, studied with SWAN model simulations

    NASA Astrophysics Data System (ADS)

    gravois, U.; Rogers, W. E.; Sheremet, A.; Jensen, T. G.

    2012-12-01

    This study focuses on the prediction of waves and surf on the nearshore reefs of South East Florida. The edge of this reefs tract, outside of Biscayne Bay, Miami, has a steep transition (1:30) from deep to shallow water and also marks the western wall of the Gulf Stream. Geographically the area is bordered by Florida, Cuba and the Bahamas Islands which block the propagation of swell energy and limit the fetch length in all directions except from the North. Related work by the authors on model hindcast validation for this area using HF radar and in situ data exposed the tendency for the wave model SWAN to over predict wave heights on these nearshore reefs for some NE swell events. Based on the findings of the hindcast validation, a series of theoretical SWAN simulations are set up to investigate the sensitivity of nearshore modeled wave heights to the deep water wave direction and also the effect of coupling with the Gulf Stream surface currents. SWAN is run on an outer wave grid centered about the nearshore reefs of interest and forced with a JONSWAP spectrum that is uniform across all of the boundaries for a suite of wave directions and frequencies. The output of the outer grid is used to force a higher resolution inner grid, run with and without Gulf Stream surface current coupling. Bulk wave parameters are output at a nearshore point location on the reef tract for analysis. There are several interesting findings as a result this study. First, there is only a narrow swell window that allows waves to propagate into the nearshore study location. This implies that a relatively small error in deep water swell angle could result in significant differences in the nearshore wave heights and is likely the source of error for the hindcast validation. Secondly, the swell window significantly shifts with the inclusion of the Gulf Stream current field. Gulf Stream refraction has more effect on shorter period wave forcing, so much so, that the optimal swell window is from the

  3. The 4 Ms CHANDRA Deep Field-South Number Counts Apportioned by Source Class: Pervasive Active Galactic Nuclei and the Ascent of Normal Galaxies

    NASA Technical Reports Server (NTRS)

    Lehmer, Bret D.; Xue, Y. Q.; Brandt, W. N.; Alexander, D. M.; Bauer, F. E.; Brusa, M.; Comastri, A.; Gilli, R.; Hornschemeier, A. E.; Luo, B.; Paolillo, M.; Ptak, A.; Shemmer, O.; Schneider, D. P.; Tozzi, P.; Vignali, C.

    2012-01-01

    We present 0.5-2 keV, 2-8 keV, 4-8 keV, and 0.5-8 keV (hereafter soft, hard, ultra-hard, and full bands, respectively) cumulative and differential number-count (log N-log S ) measurements for the recently completed approx. equal to 4 Ms Chandra Deep Field-South (CDF-S) survey, the deepest X-ray survey to date. We implement a new Bayesian approach, which allows reliable calculation of number counts down to flux limits that are factors of approx. equal to 1.9-4.3 times fainter than the previously deepest number-count investigations. In the soft band (SB), the most sensitive bandpass in our analysis, the approx. equal to 4 Ms CDF-S reaches a maximum source density of approx. equal to 27,800 deg(sup -2). By virtue of the exquisite X-ray and multiwavelength data available in the CDF-S, we are able to measure the number counts from a variety of source populations (active galactic nuclei (AGNs), normal galaxies, and Galactic stars) and subpopulations (as a function of redshift, AGN absorption, luminosity, and galaxy morphology) and test models that describe their evolution. We find that AGNs still dominate the X-ray number counts down to the faintest flux levels for all bands and reach a limiting SB source density of approx. equal to 14,900 deg(sup -2), the highest reliable AGN source density measured at any wavelength. We find that the normal-galaxy counts rise rapidly near the flux limits and, at the limiting SB flux, reach source densities of approx. equal to 12,700 deg(sup -2) and make up 46% plus or minus 5% of the total number counts. The rapid rise of the galaxy counts toward faint fluxes, as well as significant normal-galaxy contributions to the overall number counts, indicates that normal galaxies will overtake AGNs just below the approx. equal to 4 Ms SB flux limit and will provide a numerically significant new X-ray source population in future surveys that reach below the approx. equal to 4 Ms sensitivity limit. We show that a future approx. equal to 10 Ms CDF

  4. Phylogeography of the South China Field Mouse (Apodemus draco) on the Southeastern Tibetan Plateau Reveals High Genetic Diversity and Glacial Refugia

    PubMed Central

    Liu, Yang; Liao, Lihuan; Zhang, Xiuyue; Yue, Bisong

    2012-01-01

    The southeastern margin of the Tibetan Plateau (SEMTP) is a particularly interesting region due to its topographic complexity and unique geologic history, but phylogeographic studies that focus on this region are rare. In this study, we investigated the phylogeography of the South China field mouse, Apodemus draco, in order to assess the role of geologic and climatic events on the Tibetan Plateau in shaping its genetic structure. We sequenced mitochondrial cytochrome b (cyt b) sequences in 103 individuals from 47 sampling sites. In addition, 23 cyt b sequences were collected from GenBank for analyses. Phylogenetic, demographic and landscape genetic methods were conducted. Seventy-six cyt b haplotypes were found and the genetic diversity was extremely high (π = 0.0368; h = 0.989). Five major evolutionary clades, based on geographic locations, were identified. Demographic analyses implied subclade 1A and subclade 1B experienced population expansions at about 0.052-0.013 Mya and 0.014-0.004 Mya, respectively. The divergence time analysis showed that the split between clade 1 and clade 2 occurred 0.26 Mya, which fell into the extensive glacial period (EGP, 0.5-0.17 Mya). The divergence times of other main clades (2.20-0.55 Mya) were congruent with the periods of the Qingzang Movement (3.6-1.7 Mya) and the Kun-Huang Movement (1.2-0.6 Mya), which were known as the most intense uplift events in the Tibetan Plateau. Our study supported the hypothesis that the SEMTP was a large late Pleistocene refugium, and further inferred that the Gongga Mountain Region and Hongya County were glacial refugia for A. draco in clade 1. We hypothesize that the evolutionary history of A. draco in the SEMTP primarily occurred in two stages. First, an initial divergence would have been shaped by uplift events of the Tibetan Plateau. Then, major glaciations in the Pleistocene added complexity to its demographic history and genetic structure. PMID:22666478

  5. Simulation of the effects of nearby quarrying operations on ground-water flow at the South Well Field, Franklin County, Ohio

    USGS Publications Warehouse

    Nalley, Gregory M.; Haefner, Ralph J.

    1999-01-01

    gravel quarry. In this study, however, the size and shape of the CRAs differ in response to the addition of two supply wells, and the 5-year CRA for one of these wells intersects the sand and gravel quarry. Particle-tracking analysis indicates that the proportions of water from the principal water sources -- rivers, other quarries (excluding the quarry of interest), and bedrock -- stayed relatively constant among the model simulations. The number of particles that originate in the quarry of interest increased from about 1 percent of the total particles withdrawn through all wells when the 20-foot layer of undisturbed aquifer material was left intact, to 2 percent when the 20-foot layer was removed. In simulations in which the quarry of interest was filled with fine-grained sand and silt, the percentage of particles that travel through or originate in that quarry decreased to less than 1 percent of the total number of particles. Thus, the mining activities at the quarry of interest, combined with increased pumping at the two supply wells have only a small potential to change the overall water quality of water withdrawn from supply wells at the South Well Field.

  6. Hydraulic and field water-chemistry characteristics of piedmont alluvial deposits in the Middle Tyger River near Lyman, Spartanburg County, South Carolina, 2005

    USGS Publications Warehouse

    Harrelson, Larry G.; Addison, Adrian D.

    2006-01-01

    This study explores the possibility of developing a bank-filtration process to improve water quality in which alluvial deposits serve as a natural sand filter to pretreat water to be used as a secondary drinking-water source in a small piedmont reservoir along the Middle Tyger River near Lyman in Spartanburg County, South Carolina. From January 2004 to September 2005, data from 10 auger borings, 2 sediment cores, 29 ground-penetrating radar transects, and 3 temporary observation wells, and field water-chemistry data were collected and analyzed. These data were collected and used to characterize the lithology, geometry, hydraulic properties, yield potential, and water-chemistry characteristics of the alluvial deposits in the channel and on the right bank of the reservoir. The assessment was undertaken to determine if an adequate amount of water could be withdrawn from the alluvial deposits to sustain a bank-filtration process and to characterize the water chemistry of the surface water and pore water. The heterogeneous alluvial and fill material at the study site--clay, silty clay, clayey sand, fine- to coarse-grained sand, and mica--on the right bank of the Middle Tyger River ranges in thickness from 0.6 to 7 meters, has a calculated horizontal hydraulic conductivity of 1 meter per day, and yields approximately 0.07 liter per second of water. The small calculated horizontal hydraulic conductivity and water yield for these deposits restrict the use of the right bank as a potential bank-filtration site. The coarse-grained alluvial sand deposit in the channel of the Middle Tyger River, however, may be used for a limited bank-filtration process. The discharge during pumping of the channel deposit yielded water at the rate of 1.9 liters per second. The coarse-grained channel deposit is approximately 49 meters wide and 3 meters thick near the dam. At approximately 183 meters upstream from the dam, the channel narrows to roughly 9 meters and the channel deposits thin to

  7. Quantification and mapping of surface residue cover and tillage practices for maize and soybean fields in south central Nebraska-USA using Landsat imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The area cultivated under conservation tillage practices such as no-till and minimal tillage has recently increased in south central Nebraska (NE). Consequently, changes in some of the impacts of cropping systems on soil such as enhancing soil and water quality, improving soil structures and infiltr...

  8. Management of School Infrastructure in the Context of a No-Fee Schools Policy in Rural South African Schools: Lessons from the Field

    ERIC Educational Resources Information Center

    Marishane, Ramodikoe Nylon

    2013-01-01

    This study examines the management of school infrastructure in the context of the "no-fee schools" policy introduced in the South African education delivery system. Focusing on four rural schools, the study applied a qualitative method, which involved observation of infrastructure conditions prevailing at four selected schools and…

  9. Lyman Alpha Emitting Galaxies at 2 < z < 3: Towards a Calibrated Probe of Dark Energy

    SciTech Connect

    Caryl Gronwall

    2012-12-03

    The goal of this project was to establish the physical properties of Ly{alpha} emitting galaxies from redshifts of 2 to 3 in order to better calibrate the use of LAEs as probes of the large scale structure of the universe for upcoming dark energy experiments, such as the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). We have obtained narrow-band imaging of the Extended Chandra Deep Field South (ECDF-S) in two different narrow-band filters centered at Ly{alpha} at z=2.1 and 3.1. The resulting of samples of LAEs were used to determine the LAE luminosity function, equivalent width distribution and clustering properties (bias) of LAEs at these redshifts. While the results from the ECDF-S appear robust, they are based on a single field. To explore the effects of cosmic variance and galaxy environment on the physical properties of LAEs, we have also obtained narrow-band data at both redshifts (z = 2:1 and 3:1) in three additional fields (SDSS 1030+-05, the Extended Hubble Deep Field South, and CW 1255+01). The narrow-band imaging data has been reduced and LAE catalogs are being generated. We have calculated preliminary luminosity functions, equivalent width distributions, and clustering properties. We have also obtained follow-up spectroscopy in the optical (using VLT/FORS) and in the near-infrared (using Magellan/MMIRS). Since individual LAEs have too little S/N to enable meaningful fits for stellar population parameters, our previous work has analyzed stacked Spectral Energy Distributions (SEDs). SED fitting was performed on several subsets of LAEs selected by their rest-UV luminosity, UV spectral slope, Ly alpha luminosity, Equivalent Width, or rest-optical (IRAC) luminosity.

  10. When South meets South.

    PubMed

    Wulf, D

    1997-01-01

    This article describes the establishment of a new organization, Partners in Population and Development, which promotes collaboration between developing countries. The organization was an outcome of the 1994 Cairo Conference on Population and Development. The basic aim is to share technical knowledge and experience between developing countries. In rural Ha Tay province in northern Vietnam, for example, a community mapping technique for tracking contraceptive use was implemented. The mapping technique was first developed in Indonesia and transferred to Vietnam via the Indonesian national family planning coordinating board. A Bangkok-based nongovernmental group was working in Ninh Binh province with income generation among rice workers as part of a reproductive health program. Partners in Population and Development includes high ranking government officials responsible for national family planning programs from Colombia, Egypt, Kenya, Indonesia, Mexico, Morocco, Thailand, Tunisia, and Zimbabwe. In 1996, a permanent secretariat was established in Dhaka, Bangladesh. The secretariat includes a small staff consisting of an executive director and three deputies from developing countries. The secretariat will act as a clearinghouse and coordinating unit between countries and projects. The office will answer field requests for assistance and help identify potential sources of donor support. The office will operate on funding from the UN Population Fund, the World Bank, and the Rockefeller Foundation. The Partnership will diffuse the appearance that developed countries are "demographic imperialists" and offer sound financial political advice. Projects will emphasize appropriateness and sustainability. The aim is to build bridges between countries where there are barriers and to extend services beyond regional borders.

  11. The galaxy stellar mass function at 3.5 ≤z ≤ 7.5 in the CANDELS/UDS, GOODS-South, and HUDF fields

    NASA Astrophysics Data System (ADS)

    Grazian, A.; Fontana, A.; Santini, P.; Dunlop, J. S.; Ferguson, H. C.; Castellano, M.; Amorin, R.; Ashby, M. L. N.; Barro, G.; Behroozi, P.; Boutsia, K.; Caputi, K. I.; Chary, R. R.; Dekel, A.; Dickinson, M. E.; Faber, S. M.; Fazio, G. G.; Finkelstein, S. L.; Galametz, A.; Giallongo, E.; Giavalisco, M.; Grogin, N. A.; Guo, Y.; Kocevski, D.; Koekemoer, A. M.; Koo, D. C.; Lee, K.-S.; Lu, Y.; Merlin, E.; Mobasher, B.; Nonino, M.; Papovich, C.; Paris, D.; Pentericci, L.; Reddy, N.; Renzini, A.; Salmon, B.; Salvato, M.; Sommariva, V.; Song, M.; Vanzella, E.

    2015-03-01

    Context. The form and evolution of the galaxy stellar mass function (GSMF) at high redshifts provide crucial information on star formation history and mass assembly in the young Universe, close or even prior to the epoch of reionization. Aims: We used the unique combination of deep optical/near-infrared/mid-infrared imaging provided by HST, Spitzer, and the VLT in the CANDELS-UDS, GOODS-South, and HUDF fields to determine the GSMF over the redshift range 3.5 ≤ z ≤ 7.5. Methods: We used the HST WFC3/IR near-infrared imaging from CANDELS and HUDF09, reaching H ≃ 27 - 28.5 over a total area of 369 arcmin2, in combination with associated deep HST ACS optical data, deep Spitzer IRAC imaging from the SEDS programme, and deep Y and K-band VLT Hawk-I images from the HUGS programme, to select a galaxy sample with high-quality photometric redshifts. These have been calibrated with more than 150 spectroscopic redshifts in the range 3.5 ≤ z ≤ 7.5, resulting in an overall precision of σz/ (1 + z) ~ 0.037. With this database we have determined the low-mass end of the high-redshift GSMF with unprecedented precision, reaching down to masses as low as M∗ ~ 109 M⊙ at z = 4 and ~6 × 109 M⊙ at z = 7. Results: We find that the GSMF at 3.5 ≤ z ≤ 7.5 depends only slightly on the recipes adopted to measure the stellar masses, namely the photometric redshifts, the star formation histories, the nebular contribution, or the presence of AGN in the parent sample. The low-mass end of the GSMF is steeper than has been found at lower redshifts, but appears to be unchanged over the redshift range probed here. Meanwhile the high-mass end of the GSMF appears to evolve primarily in density, although there is also some evidence of evolution in characteristic mass. Our results are very different from previous mass function estimates based on converting UV galaxy luminosity functions into mass functions via tight mass-to-light relations. Integrating our evolving GSMF over mass, we

  12. Initiated by the south. South - South Cooperation.

    PubMed

    Parsons, J S

    1993-12-01

    The UNFPA Deputy Chief of the Asia and Pacific Division explains how relations between representatives of developing countries to the South have often been less than congenial and how efforts have been made to smooth the way for greater cooperation between neighbors in the region. President Soeharto of Indonesia at a G-15 submeeting of Non-Aligned Countries in Malaysia in 1990 made the first overtures to his peers. He offered to work more closely with other interested countries economically and in terms of technical assistance. Prime Minister Von Van Kiet of Vietnam took him up on his offer and visited the President in Indonesia in January 1992 to discuss family planning issues. The subsequent assistance rendered by Indonesia to Vietnam in developing its family planning program was unique in bilateral relations in the region in that it was initiated by the nonaligned countries without outside interference. The author thinks that the UNFPA should play a facilitating role financially and organizationally in what may be the beginning of a trend toward greater South-South cooperation. Any help which developing countries could render to other developing nations will certainly be appreciated in this period of waning resources from developed countries for international population programs. The author also argues that service quality in donor countries is likely to improve.

  13. Neotectonic stress field of the south-eastern East European platform as related to the Late Alpine collision deformation of the Greater Caucasus

    NASA Astrophysics Data System (ADS)

    Kopp, Mikhail L.; Kolesnichenko, Aleksei; Vassiliev, Nikita; Mostryukov, Alexandre

    2013-04-01

    In the south-eastern East European platform and Urals, as well as the young Scythyan platform, the Late Alpine collision deformations are widely spread. First of all, these are crumbled aulacogen covers (the Azov Sea, Dnieper-Donets, and Pachelma aulacogens). In some places the covers were dislocated conformably with platform basements but commonly they were partly detached from it with formation of inversion foldbelts (such as the Donets coal basin in the Alpine stage, Saratov and Kerensk-Chembar dislocations). Basements of some anteclises (the Voronezh, Tokmovo, and Volga-Urals ones) dividing the aulacogens were also involved into deformations. There the greatest upthrusting of basement onto cover can be observed (e.g., the Zhigouli upthrust). In general the thrusting and folding occurred during the Early Miocene-Quaternary, with its periodicity strictly corresponding to that of the Late Alpine tectonic phases in the Greater Caucasus: Early Miocene (the H. Stille,s Styrian phase), terminal Miocene-initial Pliocene (the Attic and Rhodanian phases), Eo-Pleistocene (the Valachian phase). Beside the synchronous occurrences, there are some other evidences of relation of intraplate deformations to the Arabia-Eurasa collision in its Caucasian region: (i) sublatitudinal (up to WNW-ESE strike) orientation of the intraplate upthrusts and folds, (ii) wide distribution of structurally manifested strike-slip zones as well as similarity in orientation and location between the right and left strike-slips considered with those of the Greater Caucasus: domains of the formers are built up to the north the domains of the latters, (iii) directed southward increasing basement involvement into the neotectonic deformations. For example, in the Donets-Azov region a basement neotectonic megafold was imposed not only onto Donets Herzinian foldbelt but also on the Precambrian basement of the Rostov high of the Ukrainian shield. To some extent, this megafold resembles a northern wing of the

  14. Variation of the Earth's magnetic field strength in South America during the last two millennia: New results from historical buildings of Buenos Aires and re-evaluation of regional data

    NASA Astrophysics Data System (ADS)

    Goguitchaichvili, Avto; Morales, Juan; Schavelzon, Daniel; Vásquez, Carlos; Gogorza, Claudia S. G.; Loponte, Daniel; Rapalini, Augusto

    2015-08-01

    The causes of the systematic decay of the Earth's Magnetic Field strength since eighteen century have been a matter of debate during the last decade. It is also well known that such variations may have completely different expressions under an area characterized with strong magnetic anomalies, such as the South Atlantic Magnetic Anomaly. To fully understand these atypical phenomena, it is crucial to retrieve the past evolution of Earth's magnetic field beyond the observatory records. We report on detailed rock-magnetic and archeointensity investigations from some well-studied historical buildings of Buenos Aires city, located at the heart of the South Atlantic Magnetic Anomaly. Samples consist of bricks, tiles, fireplaces and pottery, which are considered as highly suitable materials for archaeointensity studies. The dating is ascertained by historical documents complemented by archeological constraints. Eighteen out of 26 analyzed samples yield reliable absolute intensity determinations. The site-mean archaeointensity values obtained in this study range from 28.5 to 43.5 μT, with corresponding virtual axial dipole moments (VADMs) ranging from 5.3 to 8.04 × 1022 Am2. Most determinations obtained in the present study are in remarkable agreement with the values predicted by the time varying field model CALS10k.1b (Korte et al., 2011). For the older periods the recently available SHA.DIF.14 model (Pavon-Carrasco et al., 2014) seems to have greater resolution. South American archaeointensity database now includes absolute intensities from 400 to 1930 AD based on 63 selected archaeointensity determinations. The data set reveals several distinct periods of quite large fluctuations of intensity. However, most data are concentrated into a relatively narrow interval from AD 1250 to AD 1450. At the beginning of the record, values between 400 AD and 830 AD match well with ARCH3k.1 model. Some general features may be detected: the time intervals from about AD 400 to 950 and

  15. Early Paleozoic intracontinental orogeny in the Yunkai domain, South China Block: New insights from field observations, zircon U-Pb geochronological and geochemical investigations

    NASA Astrophysics Data System (ADS)

    Yan, Chaolei; Shu, Liangshu; Michel, Faure; Chen, Yan; Li, Cheng

    2017-01-01

    Debate on whether the Early Paleozoic tectono-magmatic event in South China is related to a subduction-collision or an intracontinental orogen has been lasted for decades within the geoscience community. This study deals with LA-ICP-MS zircon U-Pb ages, whole-rock chemistry, rare earth elements, trace elements and Hf isotopes from granitoid samples collected in the Yunkai domain in order to better constrain the Early Paleozoic tectonic evolution of the South China Block. The weighted mean 206Pb/238U ages for eight samples range from 426 Ma to 443 Ma, representing the crystallization ages of the magma. Fourteen samples were analyzed for geochemistry, all of which are characterized by a peraluminous signature with A/CNK values greater than 1.0. The REE geochemistry reveals enrichment in light rare earth element. LREE/HREE values range from 2.81 to 30.36 and (La/Yb)N vary from 1.23 to 55.14 (mean of 14 analyses is 14.69). All the samples exhibit distinct negative Ba, Sr and Nb anomalies and enrichment in Rb, Th, U and Pb. Hf isotopic analyses indicate negative εHf (t) values mainly ranging from - 3 to - 12, corresponding to two model age distributing from 1637 Ma to 2208 Ma. The geochemical analyses indicate that the Silurian granitic magmas in the Yunkai domain were derived from partial melting of crustal materials with little or no input of mantle source. These new data support the intracontinental subduction model already proposed to account for the Early Paleozoic tectonic, metamorphic and magmatic event of South China.

  16. [South] Korea.

    PubMed

    1987-04-01

    The Republic of Korea occupies approximately 38,000 square miles in the southern position of a mountaineous peninsula. It shares a land boundary with North Korea. With a population of more than 40 million people, South Korea has 1 of the highest population densities in the world. The language spoken is a Uralic language, closely akin to Japanese, Hungarian, Finnish, and Mongolian, and the traditional religions are Shamanism and Buddhism. Over the course of time, South Korea has been invaded and fought over by its neighbors. The US and the Soviet Union have never been able to reach a unification agreement for North and South Korea. The 3rd Republic era, begun in 1963, saw a time of rapid industrialization and a great deal of economic growth. The 5th Republic began with a new constitution and new elections brought about the election of a president to a 7-year term of office beginning in 1981. Economic growth has been remarkable over the last 25 years despite the fact that North Korea possesses most of the mineral and hydroelectric resources and the existing heavy industrial base built by the Japanese while South Korea has the limited agricultural resources and had, initially, a large unskilled labor pool. Serious industrial growth began in South Korea in the early 1960s and the GNP grew at an annual rate of 10% during the period 1963-78. Current GNP is now, at $2000, well beyond that of its neighbors to the north. The outlook for longterm growth is good; however, the military threat posed by North Korea and the absence of foreign economic assistance has resulted in Korea spending 1/3 of its budget on defense. South Korea is active in international affairs and in the UN. Economic realities have forced Korea to give economics priority in their foreign policy. There has been an on-again, off-again quality to dialogue between the 2 nations. However, the US is committed to maintaining peace on the Korean peninsula. In order to do so, they have supplied manpower and

  17. Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa.

    PubMed

    Dabrowski, James Michael; Balderacchi, Matteo

    2013-11-01

    A GIS based pesticide risk indicator that integrates exposure variables (i.e. pesticide application, geographic, physicochemical and crop data) and toxicity endpoints (using species sensitivity distributions) was developed to estimate the Predicted Relative Exposure (PREX) and Predicted Relative Risk (PRRI) of applied pesticides to aquatic ecosystem health in the Lourens River catchment, Western Cape, South Africa. Samples were collected weekly at five sites from the beginning of the spraying season (October) till the beginning of the rainy season (April) and were semi quantitatively analysed for relevant pesticides applied according to the local farmers spraying programme. Monitoring data indicate that physicochemical data obtained from international databases are reliable indicators of pesticide behaviour in the Western Cape of South Africa. Sensitivity analysis identified KOC as the most important parameter influencing predictions of pesticide loading derived from runoff. A comparison to monitoring data showed that the PREX successfully identified hotspot sites, gave a reasonable estimation of the relative contamination potential of different pesticides at a site and identified important routes of exposure (i.e. runoff or spray drift) of different pesticides at different sites. All pesticides detected during a monitored runoff event, were indicated as being more associated with runoff than spray drift by the PREX. The PRRI identified azinphos-methyl and chlorpyrifos as high risk pesticides towards the aquatic ecosystem. These results contribute to providing increased confidence in the use of risk indicator applications and, in particular, could lead to improved utilisation of limited resources for monitoring and management in resource constrained countries.

  18. 8. Overview of Building 1009, looking south Naval Air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Overview of Building 1009, looking south - Naval Air Station Chase Field, Building 1009, Essex Street, .68 mile South-southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

  19. 7. Staircase on south side of Building 1009, (enlisted waves' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Staircase on south side of Building 1009, (enlisted waves' barracks), looking southeast - Naval Air Station Chase Field, Building 1009, Essex Street, .68 mile South-southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

  20. 4. South side of Building 1001 (administration building), looking north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. South side of Building 1001 (administration building), looking north - Naval Air Station Chase Field, Building 1001, Independence Street, .45 mile south of intersection of Texas State Highway & Independence Street, Beeville, Bee County, TX

  1. 4. South side of quarters (executive officer's quarters), looking north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. South side of quarters (executive officer's quarters), looking north - Naval Air Station Chase Field, Quarters S, Essex Street, .45 mile South-Southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

  2. VIEW WEST, SOUTH PENN POWERHOUSE, (FROM LEFT) BLEEDER SHED, ENGINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW WEST, SOUTH PENN POWERHOUSE, (FROM LEFT) BLEEDER SHED, ENGINE HOUSE, BELT SHED, ECCENTRIC HOUSE. - South Penn Oil Company, G. M. Mead Lot 492 Lease, Morrison Run Field, Clarendon, Warren County, PA

  3. WEST TENNIS COURTS AND NONCOMMISSIONED OFFICER'S HOUSING, FROM SOUTH OAKWOOD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    WEST TENNIS COURTS AND NON-COMMISSIONED OFFICER'S HOUSING, FROM SOUTH OAKWOOD DRIVE - Hamilton Field, Tennis Courts, Escolta Avenue at Sixth Street, & Crescent Drive near South Oakwood Drive, Novato, Marin County, CA

  4. Whole-rock chemical composition of some samples from two drill hole cores in the Capps coal field, Beluga coal area, south-central Alaska

    USGS Publications Warehouse

    Hinkley, T.K.; Smith, K.S.; Peard, J.L.; Tompkins, M.L.

    1982-01-01

    Whole-rock chemical analysis was done on samples from drill cores of rocks lying atop and between coal beds in the Beluga coal area, south-central Alaska. The samples were classified as sandstone, siltstone or claystone at time of hand specimen description. Chemical data were compared to those from corresponding rocks from other sites in the conterminous United States. The study supports the following conclusions: 1. The sample suites from the two cored Alaska holes, about 1 km apart, contrast sharply in their degree of lithologic differentiation, one having relatively purer sandstones and claystones, the other having more mixed rock types. This suggests that considerable variation occurs in depositional environments and, possibly, in rock chemistry over small distances in the Beluga coal area. 2. Hand specimen inspection is a reasonably reliable way of assigning names denoting the lithologic type of Alaska rocks, and thereby making broad predictions of their whole-rock chemistry.

  5. Fuel Efficient Stoves for Darfur Camps of Internally DisplacedPersons - Report of Field Trip to North and South Darfur, Nov. 16 -Dec.17, 2005

    SciTech Connect

    Galitsky, Christina; Gadgil, Ashok; Jacobs, Mark; Lee, Yoo-Mi

    2006-02-01

    Approximately 2.2 million internally displaced persons (''IDPs'') in Darfur are living in dense camps scattered in arid areas with low fuelwood productivity. Unsustainable harvesting of fuelwood by the IDPs has created ever increasing zones of denudation, that now (in November 2005) have reached several kilometers from the camp boundaries. Leaving the safety of the camps to fetch fuelwood from farther and farther away imposes great risk and hardship on the IDP women. Three different metal fuel efficient stove (''FES'') designs were tested in Darfur IDP camps for their suitability to substantially reduce the fuelwood needs of IDPs. The mud-and-dung ''ITDG'' stoves being promoted under the current FES program were also examined and tested. A modified design of the ITDG mud-and-dung stove, ''Avi'', was developed, built and tested. Systematic informal surveys of IDP households were undertaken in North and South Darfur to understand the household parameters related to family size, food, fuel, cooking habits, cooking pots, expenditure on fuel, and preferences related to alternative ways to spend time/money if fuel could be saved. Surveys found that a significant fraction of families are missing meals for lack of fuel (50% in South Darfur, and 90% in the North Darfur camps visited by the mission). About 60% of women in South Darfur, and about 90% of women in North Darfur camps purchase fuelwood. Selling some of the food rations to purchase fuel to cook meals was significant (40%) in South Darfur and has become common (80%) in North Darfur. The LBNL mission found that two of the metal stoves and the mud-and-dung Avi can significantly reduce fuelwood consumption using the same fuel, pot, cooking methods, and food ingredients used by Darfur IDPs. The most suitable design for Darfur conditions would be a modified ''Tara'' stove. With training of the cooks in tending the fire, this stove can save 50% fuel for the IDPs. The stove costs less than $10 (US) to produce in Darfur

  6. South Louisiana Enhanced Oil Recovery/Sequestration R&D Project Small Scale Field Tests of Geologic Reservoir Classes for Geologic Storage

    SciTech Connect

    Hite, Roger

    2016-10-01

    The project site is located in Livingston Parish, Louisiana, approximately 26 miles due east of Baton Rouge. This project proposed to evaluate an early Eocene-aged Wilcox oil reservoir for permanent storage of CO2. Blackhorse Energy, LLC planned to conduct a parallel CO2 oil recovery project in the First Wilcox Sand. The primary focus of this project was to examine and prove the suitability of South Louisiana geologic formations for large-scale geologic sequestration of CO2 in association with enhanced oil recovery applications. This was to be accomplished through the focused demonstration of small-scale, permanent storage of CO2 in the First Wilcox Sand. The project was terminated at the request of Blackhorse Energy LLC on October 22, 2014.

  7. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2002-01-31

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  8. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2003-10-31

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  9. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner

    2005-01-31

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  10. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2002-04-30

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful redevelopment and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  11. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2003-07-30

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  12. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2003-01-31

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  13. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner

    2004-10-29

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re- injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  14. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner; Iraj Ershaghi

    2003-05-15

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  15. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner

    2004-07-30

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  16. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner

    2005-08-01

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  17. AN ADVANCED FRACTURE CHARACTERIZATION AND WELL PATH NAVIGATION SYSTEM FOR EFFECTIVE RE-DEVELOPMENT AND ENHANCEMENT OF ULTIMATE RECOVERY FROM THE COMPLEX MONTEREY RESERVOIR OF SOUTH ELLWOOD FIELD, OFFSHORE CALIFORNIA

    SciTech Connect

    Steve Horner

    2004-04-29

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  18. An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery from the Complex Monterey Reservoir of South Ellwood Field, Offshore California

    SciTech Connect

    Steve Horner

    2006-01-31

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the

  19. Near field receiving water monitoring of trace metals in clams (macoma balthica) and sediments near the Palo Alto Water Quality Control Plant in South San Francisco Bay, California: 2000

    USGS Publications Warehouse

    Moon, Edward; Luoma, Samuel N.; Cain, Daniel J.; Hornberger, Michelle I.; David, Carlos Primo C.

    2004-01-01

    Trace element concentrations were analyzed on samples of fine-grained sediments and clams (Macoma balthica) collected from a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report serves as a continuation of the Near Field Receiving Water Monitoring Study, which was started in 1994. The data for 2003, herein, are interpreted within that context. Metal concentrations in both sediments and clam tissue samples have been within the range of values produced by seasonal variability; however, copper and zinc, display continued decreases over the last decade. In 2003, copper in sediment was observed to drop below the ERL (Effects Range-Low) concentration for the third consecutive year and zinc concentrations never exceeded the ERL. Yearly average concentrations of copper, zinc and silver in Macoma balthica for 2003 are some of the lowest recorded since monitoring began in 1975. Mercury and selenium concentrations in sediments and clams at Palo Alto were similar to concentrations observed elsewhere in the San Francisco Bay.

  20. Near field receiving water monitoring of trace metals in clams (Macoma balthica) and sediments near the Palo Alto water quality control plant in south San Francisco Bay, California : 2002

    USGS Publications Warehouse

    Moon, Edward; David, Carlos Primo C.; Luoma, Samuel N.; Cain, Daniel J.; Hornberger, Michelle I.; Lavigne, Irene R.

    2003-01-01

    This report presents trace element concentrations analyzed on samples of fine-grained sediments and clams (Macoma balthica) collected from a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report serves as a continuation of the Near Field Receiving Water Monitoring Study, which was started in 1994. The data for 2002, herein, are interpreted within that context. Metal concentrations in both sediments and clam tissue samples have been within the range of values produced by seasonal variability. However, copper and zinc, display continued decreases. Copper in sediment was observed to drop below the ERL (Effects Range-Low) concentration for the third consecutive year and zinc concentrations never exceeded the ERL. Yearly average concentrations of copper, zinc and silver in Macoma balthica for 2002 are some of the lowest recorded since monitoring began in 1975. Mercury and selenium concentrations in sediments and clams at Palo Alto were similar concentrations observed elsewhere in the San Francisco Bay.

  1. Near field receiving water monitoring of trace metals in clams (macoma balthica) and sediments near the Palo Alto Water Quality Control Plant in South San Francisco Bay, California: 1999-2001

    USGS Publications Warehouse

    David, Carlos Primo C.; Luoma, Samuel N.; Brown, Cynthia L.; Cain, Daniel J.; Hornberger, Michelle I.; Lavigne, Irene R.

    2002-01-01

    This report presents trace element concentrations analyzed on samples of fine-grained sediments and clams (Macoma balthica) collected from a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report serves as a continuation of the Near Field Receiving Water Monitoring Study which was started in 1994. The data for 1999-2001 are interpreted within that context. Generally, metal concentrations in both sediments and clam tissue samples have been within the range of values produced by seasonal variability. Copper and zinc, however, display a continued decrease, recording the lowest winter maxima concentrations in both sediment and tissue samples in 2001. Yearly average of bioavailable copper, zinc and silver concentrations in 1999-2001 are some of the lowest recorded since monitoring began in 1975. A slight increase in mercury in sediments and selenium in tissue in early 2001 are also observed. These enrichments are believed to be mainly caused by hydrogeologic processes affecting the area although only continued sampling will confirm whether anthropogenic sources influence the concentrations of these elements.

  2. High field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter from the South Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Hertkorn, N.; Harir, M.; Koch, B. P.; Michalke, B.; Grill, P.; Schmitt-Kopplin, P.

    2012-01-01

    Non target high resolution organic structural spectroscopy of marine dissolved organic matter (DOM) isolated on 27 November 2008 by means of solid phase extraction (SPE) from four different depths in the South Atlantic Ocean off the Angola coast (3.1° E; -17.7° S; Angola basin) provided molecular level information of complex unknowns with unprecedented coverage and resolution. The sampling was intended to represent major characteristic oceanic regimes of general significance: 5 m (FISH; near surface photic zone), 48 m (FMAX; fluorescence maximum), 200 m (upper mesopelagic zone) and 5446 m (30 m above ground). 800 MHz proton (1H) nuclear magnetic resonance (NMR) 1H NMR, spectra were least affected by fast and differential transverse NMR relaxation and produced at first similar looking, rather smooth bulk NMR envelopes reflecting intrinsic averaging from massive signal overlap. Visibly resolved NMR signatures were most abundant in surface DOM but contributed at most a few percent to the total 1H NMR integral and were mainly limited to unsaturated and singly oxygenated carbon chemical environments. The relative abundance and variance of resolved signatures between samples was maximal in the aromatic region; in particular, the aromatic resolved NMR signature of the deep ocean sample at 5446 m was considerably different from that of all other samples. When scaled to equal total NMR integral, 1H NMR spectra of the four marine DOM samples revealed considerable variance in abundance for all major chemical environments across the entire range of chemical shift. Abundance of singly oxygenated CH units and acetate derivatives declined from surface to depth whereas aliphatics and carboxyl-rich alicyclic molecules (CRAM) derived molecules increased in abundance. Surface DOM contained a remarkably lesser abundance of methyl esters than all other marine DOM, likely a consequence of photodegradation from direct exposure to sunlight. All DOM showed similar overall 13C NMR

  3. 40Ar/39Ar dating, geochemistry, and isotopic analyses of the quaternary Chichinautzin volcanic field, south of Mexico City: implications for timing, eruption rate, and distribution of volcanism

    NASA Astrophysics Data System (ADS)

    Arce, J. L.; Layer, P. W.; Lassiter, J. C.; Benowitz, J. A.; Macías, J. L.; Ramírez-Espinosa, J.

    2013-12-01

    Monogenetic structures located at the southern and western ends of the Chichinautzin volcanic field (Trans-Mexican Volcanic Belt, Central Mexico) yield 40Ar/39Ar ages ranging from 1.2 Ma in the western portion of the field to 1.0-0.09 Ma in the southern portion, all of which are older than the <0.04 Ma age previously established for the entire volcanic field. These new ages indicate: (1) an eruption rate of 0.47 km3/kyr, which is much lower than the 11.7 km3/kyr previously estimated; (2) that the Chichinautzin magmatism coexisted with the Zempoala (0.7 Ma) and La Corona (1.0 Ma) polygenetic volcanoes on the southern edge of Las Cruces Volcanic Range (Trans-Mexican Volcanic Belt); and confirm (3) that the drainage system between the Mexico and Cuernavaca basins was closed during early Pleistocene forming the Texcoco Lake. Whole-rock chemistry and Sr, Nd, and Pb isotopic data indicate heterogeneous magmatism throughout the history of Chichinautzin activity that likely reflects variable degrees of slab and sediment contributions to the mantle wedge, fractional crystallization, and crustal assimilation. Even with the revised duration of volcanism within the Chichinautzin Volcanic Field, its eruption rate is higher than most other volcanic fields of the Trans-Mexican Volcanic Belt and is comparable only to the Tacámbaro-Puruaran area in the Michoacán-Guanajuato Volcanic Field to the west. These variations in eruption rates among different volcanic fields may reflect a combination of variable subduction rates of the Rivera and Cocos plates along the Middle America Trench, as well as different distances from the trench, variations in the depth with respect to the subducted slab, or the upper plate characteristics.

  4. Trap types vs productivity of significant Wilcox gas fields in the south Texas, listric growth fault trend, and the divergent origin of its two largest producers

    SciTech Connect

    Stricklin, F.L. Jr.

    1996-09-01

    Detailed mapping and analysis of 23 Wilcox fields in the subject trend indicates that gas production is related to trap type. Of total cumulative production of 3.4 TCFG, 65% is from upthrown fault blocks implying very effective fault seals due to differential pressure and/or shale smears. NE Thompsonville and Bob West fields have produced 650 and 200 BCFG, respectively, with 400 BCFG remaining reserves in the latter. The field structures are not attributed to listric growth faulting, as is suggested by their trend location. NE Thompsonville is a 9-mile-long turtle structure that originated through depositional loading of an upper slope basin, followed by tilting, and then eventual collapse of a sediment squeeze-up mound due to gravitational instability. These events provide an excellent example of basin evolution through sediment loading accompanied by withdrawal of a salt-shale substrate; the basin flanks are defined by basin-dipping listric faulting that accommodated subsidence and merge beneath its floor. Bob West Field lies along the edge of the Laramide fold belt. The 1-1/2 x 4 mile field anticline adjoins a deep-seated fault that slices over and across a buried structural ridge of probable Cretaceous age. Uplift of the latter, immediately following deposition of 20+ stacked, shelf-bar producing sands, upwarped the fault and resulted in rollover growth of the Wilcox anticline. The fault shows no downward decrease in dip typical of listric faults. NE Thompsonville and Bob West fields both produce upthrown along crestal faults. This analysis indicates that {open_quotes}high-side{close_quotes} closures, irrespective of diverse origins, have achieved head-of-the-class stature as Wilcox gas producers.

  5. Design of a field experiment for injection of natural colloids in a sandy coastal plain aquifer, Belle W. Baruch Forest Science Institute, Georgetown, South Carolina

    SciTech Connect

    Toran, L.E.; McCarthy, J.F. ); Williams, T.M. . Belle W. Baruch Forest Science Inst.)

    1990-06-01

    This report summarizes the design of field injection experiments that constitute one task in the larger project described in the report Experiments Using Natural Organics.'' In the experiment, we plan to inject a large volume of colloidal organic matter (COM) into a sandy, unconsolidated coastal aquifer and observe the migration of COM into the groundwater flow system. The report provides a brief overview of the research project, including hypotheses to be tested; describes the purpose of the field injection experiments; summarizes the site characterization preliminary to the experiments; and explains the design of the experiments. 11 figs., 5 tabs.

  6. Near-field receiving water monitoring of a benthic community near the Palo Alto Water Quality Control Plant in south San Francisco Bay: February 1974 through December 2003

    USGS Publications Warehouse

    Shouse, Michelle K.; Parcheso, Francis; Thompson, Janet K.

    2004-01-01

    Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 29-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinal clam Macoma balthica from the same area. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that could be indicative of a more stable community that is subjected to less stress. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals. Heteromastus filiformis, a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying their eggs on or in the sediment has shown a concurrent increase in dominance. These changes in species dominance reflect a change in the community from one dominated by surface dwelling, brooding species to one with species with varying life history characteristics. Analysis of the reproductive activity of Macoma balthica shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissue of this organism. Reproductive activity is presently stable with almost all animals reproducing during the two reproductive seasons (spring and fall) of most years. These findings are consistent with findings previously reported for the 1974 through 2002 period.

  7. A validation study of a rapid field-based rating system for discriminating among flow permanence classes of headwater streams in South Carolina

    EPA Science Inventory

    Rapid field-based protocols for classifying flow permanence of headwater streams are needed to inform timely regulatory decisions. Such an existing method was developed for and has been used in North Carolina since 1997. The method uses ordinal scoring of 26 geomorphology, hydr...

  8. Assessing the suitability of antibiotic resistance markers and the indirect ELISA technique for studying the competitive ability of selected Cyclopia Vent. rhizobia under glasshouse and field conditions in South Africa

    PubMed Central

    2009-01-01

    Background Symbiotic N2 fixation in legumes is constrained by many factors, including the paucity of suitable soil rhizobia To maximise growth of legume species therefore often requires the application of effective rhizobia as inoculants. But where native strains out-compete introduced rhizobia for nodule formation, it is important that the competitiveness of selected strains is tested in the field and glasshouse prior to their recommendation as commercial inoculants. However the methodology for strain identification inside nodules has often proved difficult and thus limited this field of research. In this study, the suitability of the antibiotic resistance technique (both intrinsic low-resistance fingerprinting and high-resistance marking) and the serological indirect ELISA method were assessed for their ability to detect selected Cyclopia rhizobia under glasshouse and field conditions. The four rhizobial strains that were used, namely PPRICI3, UCT40a, UCT44b and UCT61a, were isolated from wild Cyclopia species growing in the Western Cape fynbos of South Africa. Results The test strains formed two distinct groups with regard to their intrinsic resistance to the antibiotics streptomycin sulphate and spectinomycin dihydrochloride pentahydrate, making it impossible to use intrinsic antibiotic resistance to distinguish strains from within the same intrinsic resistance group. The use of strains marked with double antibiotic resistance was also investigated. A number of these strains lost their antibiotic marker tags after one plant passage; and some also lost their competitive ability. The indirect ELISA technique provided a more satisfactory method of identifying selected Cyclopia strains under both field and glasshouse conditions. The primary antibodies raised against strains UCT40a, UCT61a and UCT44b gave absorbance readings that were unambiguously negative (0.30 OD405), while those of strain PPRICI3 were ambiguous (0.50 OD405) with many false positive readings (1

  9. A field test of substance use screening devices as part of routine drunk-driving spot detection operating procedures in South Africa.

    PubMed

    Matzopoulos, Richard; Lasarow, Avi; Bowman, Brett

    2013-10-01

    This pilot study aimed to test four substance use screening devices developed in Germany under local South African conditions and assess their utility for detecting driving under the influence of drugs (DUID) as part of the standard roadblock operations of local law enforcement agencies. The devices were used to screen a sample of motorists in the Gauteng and Western Cape provinces. The motorists were diverted for screening at roadblocks at the discretion of the law enforcement agencies involved, as per their standard operating procedures. Fieldworkers also administered a questionnaire that described the screening procedure, as well as information about vehicles, demographic information about the motorists and their attitudes to the screening process during testing. Motorists tested positive for breath alcohol in 28% of the 261 cases tested. Oral fluid was screened for drugs as per the standard calibrated cut-offs of all four devices. There were 14 cases where the under-influence drivers tested positive for alcohol and drugs simultaneously, but 14% of the 269 drivers drug-screened tested positive for drugs only. After alcohol, amphetamine, methamphetamine and cocaine were the most common drugs of impairment detected. The results suggest that under normal enforcement procedures only 76% of drivers impaired by alcohol and other drugs would have been detected. In more than 70% of cases the tests were administered within 5 min and this is likely to improve with more regular use. It was clear that the pilot screening process meets global testing standards. Although use of the screening devices alone would not serve as a basis for prosecution and provisions would need to be made for the confirmation of results through laboratory testing, rollout of this screening process would improve operational efficiency in at least two ways. Firstly, the accuracy of the tests will substantially decrease confirmatory test loads. Secondly, laboratory drug testing can be restricted to

  10. Generation of high-resolution wind fields from the dense meteorological station network WegenerNet in South-Eastern Austria

    NASA Astrophysics Data System (ADS)

    Schlager, Christoph; Kirchengast, Gottfried; Fuchsberger, Jürgen

    2016-04-01

    To investigate weather and climate on a local scale as well as for evaluating regional climate models (RCMs) the Wegener Center at the University of Graz established the long-term field experiment WegenerNet Feldbach region, a dense grid of 153 meteorological stations. The observations of these stations are managed by an automatic WegenerNet Processing system. This system includes a quality check of collected observations and a Data Product Generator (DPG), among other subsystems. Products already implemented in the DPG are gridded weather and climate products, generated from the main parameters temperature, precipitation and relative humidity (Kirchengast et. al., Bull. Amer. Meteor. Soc., 95, 227-242, 2014). Missing elements are gridded wind fields from wind observations. Wind is considered as one of the most difficult meteorological variables to model and depends on many different parameters such as topography and surface roughness. Therefore a simple interpolation can only be performed in case of uniform characteristics of landscape. The presentation introduces our method of generation of wind fields from near real-time observations of the WegenerNet. Purpose of this work is to provide a database with 3D wind fields in a high spatial and time resolution as addition to the existing products, for evaluating convection permitting climate models as well as investigating weather and climate on a local scale. Core of the application is the diagnostic California Meteorological Model (CALMET). This model computes 3D wind fields based on meteorological observational data, a digital elevation model and land use categories. The application generates the required input files from meteorological stations of the WegenerNet Feldbach region and triggers the start of the CALMET model with these input files. In a next step the modeled wind fields are stored automatically every 30 minutes with a spatial resolution of 100 x 100 m in the WegenerNet database. To verify the

  11. The use of MODIS data to derive acreage estimations for larger fields: A case study in the south-western Rostov region of Russia

    NASA Astrophysics Data System (ADS)

    Fritz, S.; Massart, M.; Savin, I.; Gallego, J.; Rembold, F.

    2008-12-01

    Recent developments in remote sensing technology, in particular improved spatial and temporal resolution, open new possibilities for estimating crop acreage over larger areas. Remotely sensed data allow in some cases the estimation of crop acreage statistics independently of sub-national survey statistics, which are sometimes biased and incomplete. This work focuses on the use of MODIS data acquired in 2001/2002 over the Rostov Oblast in Russia, by the Azov Sea. The region is characterised by large agricultural fields of around 75 ha on average. This paper presents a methodology to estimate crop acreage using the MODIS 16-day composite NDVI product. Particular emphasis is placed on a good quality crop mask and a good quality validation dataset. In order to have a second dataset which can be used for cross-checking the MODIS classification a Landsat ETM time series for four different dates in the season of 2002 was acquired and classified. We attempted to distinguish five different crop types and achieved satisfactory and good results for winter crops. Three hundred and sixty fields were identified to be suitable for the training and validation of the MODIS classification using a maximum likelihood classification. A novel method based on a pure pixel field sampling is introduced. This novel method is compared with the traditional hard classification of mixed pixels and was found to be superior.

  12. Reconsideration at Field Scale of the Relationship between Hydraulic Conductivity and Porosity: The Case of a Sandy Aquifer in South Italy

    PubMed Central

    2014-01-01

    To describe flow or transport phenomena in porous media, relations between aquifer hydraulic conductivity and effective porosity can prove useful, avoiding the need to perform expensive and time consuming measurements. The practical applications generally require the determination of this parameter at field scale, while most of the empirical and semiempirical formulas, based on grain size analysis and allowing determination of the hydraulic conductivity from the porosity, are related to the laboratory scale and thus are not representative of the aquifer volumes to which one refers. Therefore, following the grain size distribution methodology, a new experimental relation between hydraulic conductivity and effective porosity, representative of aquifer volumes at field scale, is given for a confined aquifer. The experimental values used to determine this law were obtained for both parameters using only field measurements methods. The experimental results found, also if in the strict sense valid only for the investigated aquifer, can give useful suggestions for other alluvial aquifers with analogous characteristics of grain-size distribution. Limited to the investigated range, a useful comparison with the best known empirical formulas based on grain size analysis was carried out. The experimental data allowed also investigation of the existence of a scaling behaviour for both parameters considered. PMID:25180202

  13. Multicentre studies of insecticide-treated durable wall lining in Africa and South-East Asia: entomological efficacy and household acceptability during one year of field use

    PubMed Central

    2012-01-01

    Background Indoor residual spraying (IRS) is a primary method of malaria vector control, but its potential impact is constrained by several inherent limitations: spraying must be repeated when insecticide residues decay, householders can tire of the annual imposition and campaign costs are recurrent. Durable lining (DL) can be considered an advanced form of long-lasting IRS where insecticide is gradually released from an aesthetically attractive wall lining material to provide vector control for several years. A multicentre trial was carried out in Equatorial Guinea, Ghana, Mali, South Africa and Vietnam to assess the feasibility, durability, bioefficacy and household acceptability of DL, compared to conventional IRS or insecticide-treated curtains (LLITCs), in a variety of operational settings. Methods This study was conducted in 220 households in traditional rural villages over 12-15 months. In all sites, rolls of DL were cut to fit house dimensions and fixed to interior wall surfaces (usually with nails and caps) by trained teams. Acceptability was assessed using a standardized questionnaire covering such topics as installation, exposure reactions, entomology, indoor environment, aesthetics and durability. Bioefficacy of interventions was evaluated using WHO cone bioassay tests at regular intervals throughout the year. Results The deltamethrin DL demonstrated little to no decline in bioefficacy over 12-15 months, supported by minimal loss of insecticide content. By contrast, IRS displayed a significant decrease in bioactivity by 6 months and full loss after 12 months. The majority of participants in DL households perceived reductions in mosquito density (93%) and biting (82%), but no changes in indoor temperature (83%). Among those households that wanted to retain the DL, 73% cited protective reasons, 20% expressed a desire to keep theirs for decoration and 7% valued both qualities equally. In Equatorial Guinea, when offered a choice of vector control product at

  14. Ground based characterization of biomass burning aerosols during the South American Biomass Burning Analysis (SAMBBA) field experiment in Brazil during Sept - Oct 2012

    NASA Astrophysics Data System (ADS)

    Artaxo, Paulo; Ferreira de Brito, Joel; Varanda Rizzo, Luciana; Johnson, Ben; Haywood, Jim; Longo, Karla; Freitas, Saulo; Coe, Hugh

    2013-04-01

    Biomass burning is one of the major drivers for atmospheric composition in the Southern hemisphere. In Amazonia, deforestation rates have been steadily decreasing, from 27,000 Km² in 2004 to about 5,000 Km² in 2011. This large reduction (by factor 5) was not followed by similar reduction in aerosol loading in the atmosphere due to the increase in agricultural fires. AERONET measurements from 5 sites show a large year-to year variability due to climatic and socio-economic issues. Besides this strong reduction in deforestation rate, biomass burning emissions in Amazonia increases concentrations of aerosol particles, CO, ozone and other species, and also change the surface radiation balance in a significant way. To complement the long term biomass burning measurements in Amazonia, it was organized in 2012 the intensive campaign of the South American Biomass Burning Analysis (SAMBBA) experiment with an airborne and a ground based components. A sampling site was set up at Porto Velho, with measurements of aerosol size distribution, optical properties such as absorption and scattering at several wavelengths, organic aerosol characterization with an ACSM - Aerosol Chemical Speciation Monitor. CO, CO2 and O3 were also measured to characterize combustion efficiency and photochemical processes. Filters for trace elements measured by XRF and for OC/EC determined using a Sunset instrument were also collected. An AERONET CIMEL sunphotometer was operated in parallel with a multifilter radiometer (MFR). A large data set was collected from August to October 2012. PM2.5 aerosol concentrations up to 250 ug/m3 were measured, with up to 20 ug/m3 of black carbon. Ozone went up to 60 ppb at mid-day in August. At night time ozone was consumed completely most of the time. ACSM shows that more than 85% of the aerosol mass was organic with a clear diurnal pattern. The organic aerosol volatility was very variable depending on the air mass sampled over Porto Velho. Aerosol optical depth at

  15. Seasonal abundance, species composition, and population dynamics of stink bugs in production fields of early and late soybean in South Arkansas.

    PubMed

    Smith, J F; Luttrell, R G; Greene, J K

    2009-02-01

    From 2003 through 2007, densities of stink bugs were monitored weekly in 297 commercial production fields of early and late soybean, Glycine max L. Merrill, in southeast and southwest Arkansas. The goal of this research was to better understand seasonal abundance, species composition, and population dynamics of pentatomids as a benchmark reference for future management systems. Thirty-five percent of all the 25-sweep samples taken in soybean contained at least one stink bug specimen. The average density (mean +/- SEM) of stink bugs across all soybean samples was 1.84 +/- 0.06 per 25 sweeps. Overall, Nezara viridula L. was the most abundant species, although Euschistus serous (Say) was frequently found in soybean samples (18% of all samples). Peak densities of stink bugs in soybean were observed during the full-pod (R7) developmental stage. Approximately 25% of all soybean fields sampled had threshold densities (nine or more per 25 sweeps) at some time during the year, although 82 and 78% of fields in 2006 and 2007, respectively, reached threshold. At low densities (one to three stink bugs per 25 sweeps), E. serous comprised 50% of total stink bugs, but at high densities (> 71 stink bugs per 25 sweeps), N. viridula comprised 81% of total stink bugs. Piezodorus guildinii (Westwood) was observed as a pest of Arkansas soybean in 2005, and reproduction in soybean was documented in 2006 and 2007. Stink bugs seem to be a serious and increasingly important pest of soybean in southern Arkansas. Crop phenological development is a key factor in predicting colonization and population growth of stink bugs on Arkansas soybean, regardless of geographic region or type of soybean production system.

  16. An integrated study of the Grayburg/San Andres reservoir, Foster and South Cowden fields, Ector County, Texas. Quarterly report, April 1--June 31, 1996. Revision

    SciTech Connect

    Trentham, R.C.; Weinbrandt, R.; Robertson, W.

    1996-10-17

    The principal objective of this research is to demonstrate in the field that 3D seismic data can be used to aid in identifying porosity zones, permeability barriers and thief zones and thereby improve waterflood design. Geologic and engineering data will be integrated with the geophysical data to result in a detailed reservoir characterization. Reservoir simulation will then be used to determine infill drilling potential and the optimum waterflood design for the project area. This design will be implemented and the success of the waterflood evaluated.

  17. An integrated study of the Grayburg/San Andres Reservoir, Foster and South Cowden fields, Ector County, Texas. Quarterly report, April 1--June 31, 1996

    SciTech Connect

    Trentham, R.C.; Weinbrandt, R.; Robertson, W.

    1996-10-17

    The principal objective of this research is to demonstrate in the field that 3D seismic data can be used to aid in identifying porosity zones, permeability barriers and thief zones and thereby improve waterflood design. Geologic and engineering data will be integrated with the geophysical data to result in a detailed reservoir characterization. Reservoir simulation will then be used to determine infill drilling potential and the optimum waterflood design for the project area. This design will be implemented and the success of the waterflood evaluated.

  18. An integrated study of the Grayburg/San Andres Reservoir, Foster and South Cowden Fields, Ector County, Texas. Quarterly progress report, April 1995--June 1995

    SciTech Connect

    Reeves, J.J.; Rowland, D.A.; Trentham, R.C.

    1995-10-01

    The principal objective of this research is to demonstrate in the field that 3D seismic data can be used to aid in identifying porosity zones, permeability barriers and thief zones and thereby improve waterflood design. Geologic and engineering data will be integrated with the geophysical data to result in a detailed reservoir characterization. Reservoir simulation will then be used to determine infill drilling potential and the optimum waterflood design for the project area. This design will be implemented and the success of the waterflood evaluated.

  19. Deployment and Testing of KELT-South

    NASA Astrophysics Data System (ADS)

    Kuhn, Rudi; Pepper, J.; Stassun, K.; James, D. J.; Siverd, R. J.

    2010-01-01

    The KELT-South telescope is a wide-field, small aperture robotic telescope recently deployed at Sutherland, South Africa. Based on the design of the KELT-North telescope in Arizona, KELT-South will survey the southern sky for planetary transits of bright (8 < V < 10) stars. It consists of a 4k by 4k Apogee CCD camera with a medium format telephoto lens, mounted on a Paramount ME mount. Here we describe the instrument, robotic operations, site, and observing strategy. We also describe the instrument's performance and prospects for planet discovery based on initial measurements and observations. The KELT-South project is funded by the Vanderbilt Initiative in Data-intensive Astrophysics (VIDA) at Vanderbilt University, and by the NSF PAARE grant AST-0849736. We also thank the South African Astronomical Observatory (SAAO) for cooperation with KELT-South and operational support.

  20. Strategies for reservoir characterization and identification of incremental recovery opportunities in mature reservoirs in Frio Fluvial-Deltaic sandstones, south Texas: An example from Rincon Field, Starr County. Topical report

    SciTech Connect

    McRae, L.; Holtz, M.; Hentz, T.

    1995-11-01

    Fluvial-deltaic sandstone reservoirs in the United States are being abandoned at high rates, yet they still contain more than 34 billion barrels of unrecovered oil. The mature Oligocene-age fluvial-deltaic reservoirs of the Frio Formation along the Vicksburg Fault Zone in South Texas are typical of this class in that, after more than three decades of production, they still contain 61 percent of the original mobile oil in place, or 1.6 billion barrels. This resource represents a tremendous target for advanced reservoir characterization studies that integrate geological and engineering analysis to locate untapped and incompletely drained reservoir compartments isolated by stratigraphic heterogeneities. The D and E reservoir intervals of Rincon field, Starr County, South Texas, were selected for detailed study to demonstrate the ability of advanced characterization techniques to identify reservoir compartmentalization and locate specific infield reserve-growth opportunities. Reservoir architecture, determined through high-frequency genetic stratigraphy and facies analysis, was integrated with production history and facies-based petrophysical analysis of individual flow units to identify recompletion and geologically targeted infill drilling opportunities. Estimates of original oil in place versus cumulative production in D and E reservoirs suggest that potential reserve growth exceeds 4.5 million barrels. Comparison of reservoir architecture and the distribution of completions in each flow unit indicates a large number of reserve-growth opportunities. Potential reserves can be assigned to each opportunity by constructing an Sooh map of remaining mobile oil, which is the difference between original oil in place and the volumes drained by past completions.

  1. Detection of low-chloride fluids beneath a cold seep field on the Nankai accretionary wedge off Kumano, south of Japan

    NASA Astrophysics Data System (ADS)

    Toki, T.; Tsunogai, U.; Gamo, T.; Kuramoto, S.; Ashi, J.

    2004-11-01

    Chemical and isotopic characteristics were determined for interstitial waters extracted from surface sediments in and around dense biological communities on the seafloor of the Nankai accretionary prism off Kumano, south of Japan. We found the following unique features when compared with usual interstitial water samples of normal seafloor in those of samples from bacterial mats on the Oomine Ridge, one of the outer ridge in the Nankai accretionary prism: (1) significant depletion of chloride concentration (maximum 10% depletion from bottom seawater), (2) high concentrations of CH4 and ΣCO2 (more than 660 μmol/kg and 60 mmol/kg, respectively), (3) sulfate depletion (more than 90% depletion compared to bottom seawater), and (4) δDH2O and δ18OH2O depletion [more than 4‰ and 0.7‰ depletion, respectively, compared to standard mean ocean water (SMOW)]. The highest CH4 value among these samples was comparable to the highest value so far reported at one of the most active seep areas in the Nankai Trough, suggesting that these sites should also be regarded as one of the most active seep sites in the Nankai Trough. The chemical compositions of the samples taken from the Oomine Ridge strongly suggest that the fluid originates not from normal sediment-seawater interaction at the sediment surface of hemipelagic environments, but from active seepage of fluids that are rich in CH4 and ΣCO2, depleted in Cl- and SO42-, and low in δDH2O and δ18OH2O compared to normal seawater. Values for the carbon isotopic composition (δ13CCH4) of the dissolved methane in the interstitial fluid [less than -70‰ PeeDee Belemnite (PDB)] and for the C2H6/CH4 ratio (less than 10-3) suggest that the methane originates from microbial production in a relatively shallow layer of sediment, not from the deep sedimentary layer of higher temperature than 60 °C at the depth of more than 300 m below the seafloor. The Cl-=0 mmol/kg extrapolated end-member δDH2O and δ18OH2O values of low

  2. An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery from the Complex Monterey Reservoir of South Ellwood Field, Offshore California

    SciTech Connect

    Horner, Steve; Ershaghi, Iraj

    2006-06-30

    Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to over 10,000,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intended to investigate, map and characterize field fracture patterns and the reservoir conduit system. In the first phase of the project, state of the art borehole imaging technologies including FMI, dipole sonic, interference tests and production logs were employed to characterize fractures and micro faults. These data along with the existing database were used in the construction of a new geologic model of the fracture network. An innovative fracture network reservoir simulator was developed to better understand and manage the aquifer’s role in pressure maintenance and water production. In the second phase of this project, simulation models were used to plan the redevelopment of the field using high angle wells. Correct placement of the wells is critical to intersect the best-developed fracture zones and to avoid producing large volumes of water from the water leg. Particula r attention was paid to those areas of the field that have not been adequately developed with the existing producers. In cooperation with the DOE and the PTTC, the new data and the new fracture simulation model were shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the methodologies developed in this project. This report presents a summary of all technical work conducted during Budget Periods I

  3. Distribution of Zelus longipes (Hemiptera: Reduviidae) in south Florida corn fields and its functional response to corn-infesting picture-winged flies (Diptera: Ulidiidae).

    PubMed

    Kalsi, M; Seal, D R; Nuessly, G S; Capinera, J L; Martin, C G

    2014-10-01

    The milkweed assassin bug, Zelus longipes (L.) (Hemiptera: Reduviidae), is a generalist predator and a potential biological control agent of picture-winged flies (Diptera: Ulidiidae), which cause considerable economic damage to sweet corn yields in Florida. We studied the potential of Z. longipes as a biocontrol agent of four ulidiid pests in corn fields: Euxesta stigmatias Loew, Euxesta eluta Loew, Euxesta annonae F., and Chaetopsis massyla Walker. Within-plant and within-field distributions of Z. longipes and ulidiids and functional responses of Z. longipes to ulidiid prey were determined. Highest numbers of Z. longipes and ulidiids in the R1, R2, and R3 corn stages were generally in the basal or middle leaves at 09:00 h EST, ears at 13:00 h EST, and top and tassel at 17:00 h EST. Hence, there seemed to be a coordinated migration of Z. longipes and ulidiids from the lowest to the highest parts of the corn plant during the day. Within the corn field, aggregated (clumped) distributions were most common for Z. longipes and ulidiids especially in the later R2 and R3 stages based on Taylor's power law, Iwao's patchiness regression, index of dispersion, and Lloyd's patchiness indices of dispersion. However, predator and prey populations were lower in the R1 stage, and there were inconsistent results for dispersion indices among times of day and between predators and prey. Ulidiid distributions in R1 were mostly regular (uniform) at 13:00 h EST, but aggregated at 09:00 h and 17:00 h. However, Z. longipes R1 distributions were mostly aggregated at 13:00 h, but random or regular at 09:00 h and 17:00 h EST. Handling times for male and female Z. longipes were 1.0-1.39 h and 0.67-0.97 h, respectively, and each had a type II functional response to E. stigmatias, E. eluta, and E. annonae and consumed about five flies per day. Although the population abundance of Z. longipes can vary between seasons, it appears to be a promising biocontrol agent of ulidiid flies in corn.

  4. Reproductive biomarkers responses induced by xenoestrogens in the characid fish Astyanax fasciatus inhabiting a South American reservoir: An integrated field and laboratory approach

    SciTech Connect

    Prado, Paula S.; Pinheiro, Ana Paula B.; Bazzoli, Nilo; Rizzo, Elizete

    2014-05-01

    Field studies evaluating the effects of endocrine disruption chemicals (EDCs) on the fish reproduction are scarce worldwide. The goal of this study was to assess hepatic levels of vitellogenin (Vtg), zona radiata proteins (Zrp) and insulin-like growth factors (IGF-I and IGF-II), and relating them to reproductive endpoints in a wild fish population habiting a reservoir that receive domestic sewage, agricultural and industrial residues. Adult fish Astyanax fasciatus were sampled during the reproductive season in five sites from the Furnas Reservoir, Grande River, and Paraguay–Paraná basin. As a control to field data, fish were experimentally exposed via dietary intake, to oestradiol benzoate (OB) for 7 days. Fish from site with little anthropogenic interference showed hepatic levels of Vtg, Zrp and IGF-I and IGF-II similar to those from the non-treated experimental group. In sites located immediately downstream from the municipal wastewater discharges, the water total oestrogen was >120 ng/l, and male fish displayed increased Vtg and Zrp and decreased IGF-I levels similar to OB treated fish. In females, levels of Vtg, Zrp, IGF-I and IGF-II suggest an impairment of final oocyte maturation and spawning, as also detected by frequency of over-ripening, follicular atresia and fecundity. At the sites that receive agricultural and industrial residues, the water total oestrogen was <50 ng/l and females showed decreased Zrp and increased IGF-II levels associated to reduced diameter of vitellogenic follicles, indicating an inhibition of oocyte growth. Overall, the current study reports oestrogenic contamination impairing the reproduction of a wild fish from a hydroeletric reservoir and, the data contribute to improving the current knowledge on relationship between hepatic Vtg, Zrp and IGF-I and IGF-II, and reproductive endpoints in a teleost fish. In addition, our data point out novel reproductive biomarkers (IGF-I, IGF-II and over-ripening) to assessing xenoestrogenic

  5. South-South Migration and Education: The Case of People of Haitian Descent Born in the Dominican Republic

    ERIC Educational Resources Information Center

    Bartlett, Lesley

    2012-01-01

    The world is witnessing an era of unprecedented human mobility and much of this movement entails migration between countries in the global south. This article contributes to the development of an important new line of inquiry within the field of comparative and international education: South-South migration and education. In the first section, I…

  6. Glaciers of South America

    USGS Publications Warehouse

    Williams, Richard S.; Ferrigno, Jane G.

    1998-01-01

    Landsat images, together with maps and aerial photographs, have been used to produce glacier inventories, define glacier locations, and study glacier dynamics in the countries of South America, along with the Andes Mountains. In Venezuela, Colombia, Ecuador, and Bolivia, the small glaciers have been undergoing extensive glacier recession since the late 1800's. Glacier-related hazards (outburst floods, mud flows, and debris avalanches) occur in Colombia, in Ecuador, and associated with the more extensive (2,600 km2) glaciers of Peru. The largest area of glacier ice is found in Argentina and Chile, including the northern Patagonian ice field (about 4,200 km2) and the southern Patagonian ice field (about 13,000 km2), the largest glacier in the Southern Hemisphere outside Antarctica.

  7. Reproductive biomarkers responses induced by xenoestrogens in the characid fish Astyanax fasciatus inhabiting a South American reservoir: an integrated field and laboratory approach.

    PubMed

    Prado, Paula S; Pinheiro, Ana Paula B; Bazzoli, Nilo; Rizzo, Elizete

    2014-05-01

    Field studies evaluating the effects of endocrine disruption chemicals (EDCs) on the fish reproduction are scarce worldwide. The goal of this study was to assess hepatic levels of vitellogenin (Vtg), zona radiata proteins (Zrp) and insulin-like growth factors (IGF-I and IGF-II), and relating them to reproductive endpoints in a wild fish population habiting a reservoir that receive domestic sewage, agricultural and industrial residues. Adult fish Astyanax fasciatus were sampled during the reproductive season in five sites from the Furnas Reservoir, Grande River, and Paraguay-Paraná basin. As a control to field data, fish were experimentally exposed via dietary intake, to oestradiol benzoate (OB) for 7 days. Fish from site with little anthropogenic interference showed hepatic levels of Vtg, Zrp and IGF-I and IGF-II similar to those from the non-treated experimental group. In sites located immediately downstream from the municipal wastewater discharges, the water total oestrogen was >120 ng/l, and male fish displayed increased Vtg and Zrp and decreased IGF-I levels similar to OB treated fish. In females, levels of Vtg, Zrp, IGF-I and IGF-II suggest an impairment of final oocyte maturation and spawning, as also detected by frequency of over-ripening, follicular atresia and fecundity. At the sites that receive agricultural and industrial residues, the water total oestrogen was <50 ng/l and females showed decreased Zrp and increased IGF-II levels associated to reduced diameter of vitellogenic follicles, indicating an inhibition of oocyte growth. Overall, the current study reports oestrogenic contamination impairing the reproduction of a wild fish from a hydroeletric reservoir and, the data contribute to improving the current knowledge on relationship between hepatic Vtg, Zrp and IGF-I and IGF-II, and reproductive endpoints in a teleost fish. In addition, our data point out novel reproductive biomarkers (IGF-I, IGF-II and over-ripening) to assessing xenoestrogenic

  8. The effects of sediment and mercury mobilization in the South Yuba River and Humbug Creek Confluence Area, Nevada County, California: Concentrations, speciation, and environmental fate-Part 1: Field characterization

    USGS Publications Warehouse

    Fleck, Jacob A.; Alpers, Charles N.; Marvin-DiPasquale, Mark; Hothem, Roger L.; Wright, Scott A.; Ellett, Kevin; Beaulieu, Elizabeth; Agee, Jennifer L.; Kakouros, Evangelos; Kieu, Le H.; Eberl, Dennis D.; Blum, Alex E.; May, Jason T.

    2011-01-01

    Millions of pounds of mercury (Hg) were deposited in the river and stream channels of the Sierra Nevada from placer and hard-rock mining operations in the late 1800s and early 1900s. The resulting contaminated sediments are relatively harmless when buried and isolated from the overlying aquatic environment. The entrained Hg in the sediment constitutes a potential risk to human and ecosystem health should it be reintroduced to the actively cycling portion of the aquatic system, where it can become methylated and subsequently bioaccumulated in the food web. Each year, sediment is mobilized within these fluvial systems during high stormflows, transporting hundreds of tons of Hg-laden sediment downstream. The State of California and resource-management agencies, including the Bureau of Land Management (BLM) and the U.S. Forest Service, are concerned about additional disturbances, such as from suction gold dredging activities, which have the potential to mobilize Hg associated with buried sediment layers elevated in Hg that are otherwise likely to remain buried under normal storm conditions. The BLM initiated a study looking at the feasibility of removing Hg-contaminated sediment at the confluence of the South Yuba River and Humbug Creek in the northern Sierra Nevada of California by using standard suction-dredge technology. Additionally, the California State Water Resources Control Board (SWRCB) supported a comprehensive characterization of the intended dredge site. Together, the BLM and SWRCB supported a comprehensive characterization of Hg contamination at the site and the potential effects of sediment disturbance at locations with historical hydraulic mining debris on downstream environments. The comprehensive study consisted of two primary components: field studies and laboratory experiments. The field component, described in this report, had several study elements: 1) a preliminary, small-scale, in-stream dredge test; 2) comprehensive characterization of grain

  9. Laboratory and field trials with two Bacillus thuringiensis var. israelensis products for Simulium(Diptera: Nematocera) control in a small polluted river in South Africa.

    PubMed

    Car, M

    1984-06-01

    The effects on Simulium adersi and S. hargreavesi larvae of 2 Bacillus thuringiensis var. israelensis products, the liquid formulation "Teknar" (Sandoz) and a powder formulation produced by the Ben Gurion University, Israel, were compared in the laboratory and in the Pienaars River. This river was heavily polluted with effluent from a nearby sewage works and contained 77 mg/l chloride. In the laboratory S. adersi and S. hargreavesi larvae showed 26; 48; 95 and 100% mortality 6 hours after a 10-minute application of 0,8; 1,6; 3,2 and 16 ppm "Teknar" in rain water. The powder formulation applied at 0,2; 1,0; 2,0 and 30 ppm resulted in a 7; 17; 35 and 100% mortality. In polluted river-water the mortality was 85% with 16 ppm "Teknar" and 80% with 30 ppm B. thuringiensis powder. In the field trials "Teknar" at 1,6 ppm and B. thuringiensis powder at 3 ppm did not cause any larval mortality at flow rates of 3 060 l/min and 2 040 l/min, respectively. However, 24 hours after application of the powder formulation, numbers of S. hargreavesi decreased significantly (P = 0,05) 20 m below the application point. A further 24 hours later, after "Teknar" had been applied, the numbers of S. adersi decreased and those of Chironomidae increased significantly. There was a significant increase in S. hargreavesi 200 m downstream after treatment with "Teknar".

  10. Evaluation of solitary waves as a mechanism for oil transport in poroelastic media: A case study of the South Eugene Island field, Gulf of Mexico basin

    SciTech Connect

    Joshi, Ajit; Appold, Martin S.; Nunn, Jeffrey A.

    2012-11-01

    Hydrocarbons in shallow reservoirs of the Eugene Island 330 field in the Gulf of Mexico basin are thought to have migrated rapidly along low permeability sediments of the Red fault zone as discrete pressure pulses from source rocks at depths of about 4.5 km. The aim of this research was to evaluate the hypothesis that these pressure pulses represent solitary waves by investigating the mechanics of solitary wave formation and motion and wave oil transport capability. A two-dimensional numerical model of Eugene Island minibasin formation predicted overpressures at the hydrocarbon source depth to increase at an average rate of 30 Pa/yr, reaching 52 MPa by the present day and oil velocities of 1E-12 m/yr, far too low for kilometer scale oil transport to fill shallow Plio-Pleistocene reservoirs within the 3.6 million year minibasin history. Calculations from a separate one-dimensional model that used the pressure generation rate from the two-dimensional model showed that solitary waves could only form and migrate within sediments that have very low permeabilities between 1-25 to 1-24 m2 and that are highly overpressured to 91-93% of lithostatic pressure. Solitary waves were found to have a maximum pore volume of 105 m3, to travel a maximum distance of 1-2 km, and to have a maximum velocity of 1-3 m/yr. Based on these results, solitary waves are unlikely to have transported oil to the shallowest reservoirs in the Eugene Island field in a poroelastic fault gouge rheology at the pressure generation rates likely to have been caused by disequilibrium compaction and hydrocarbon generation. However, solitary waves could perhaps be important agents for oil transport in other locations where reservoirs are closer to the source rocks, where the pore space is occupied by more than one fluid, or where sudden fracturing of overpressured hydrocarbon source sediments would allow the solitary waves to propagate as shock waves. Hydrocarbons in shallow reservoirs of the Eugene Island 330

  11. Provenance of the Gueydan Formation, south Texas: Implications for the late Oligocene—early Miocene tectonic evolution of the Trans-Pecos volcanic field

    NASA Astrophysics Data System (ADS)

    Parker, Don F.; Krystinik, Jon G.; McKee, Bryce J.

    1988-12-01

    Coarse fluvial deposits of the Soledad Member of the Gueydan Formation were derived from the Trans-Pecos volcanic field (TPVF), but the proportions of clast types in the deposits do not match present outcrop abundances in the TPVF. Basalt and mafic trachyte are most abundant in Soledad conglomerate and sandstone, durable trachyte forming the largest clasts. In contrast, the surviving remnant of the TPVF is dominated by silicic lava and tuff. The basaltic and trachytic clasts most closely resemble rocks within some of the younger (˜32-27 Ma) units in the Davis, Chinati, and Bofecillos mountains of the TPVF. Our data suggest that these and similar units were much more widespread at the time of Gueydan deposition and were largely stripped from the TPVF during erosion (1-2 km). Gueydan deposition may have been associated with regional uplift of the TPVF accompanying the onset of Basin and Range extension. This uplift would have provided the steep gradient necessary to transport coarse detritus from the TPVF to the Gulf Coast. Basin and Range extension eventually disrupted the course of the ancestral Rio Grande-Rio Conchos, thereby cutting off the supply of volcanic detritus and ending Gueydan deposition.

  12. [South] Yemen.

    PubMed

    1989-12-01

    Yemen has an area of 112,000 square miles, the terrain is mountainous in the interior, and has a flat and sandy coast. The climate is extremely hot with little rainfall. 2.2 million is the population level with an annual growth rate of 2.6%. The ethnic background is Arab, the religion is Islam and the language is Arabic. 50 years is the average life expectancy and the infant mortality rate is 142/1000. The labor force is 42% agriculture, fisheries, industry and commerce 31%, and services 27%. A republic formed in 1967, the government has a constitution approved in 1978. They have 1 party, the Yemeni Socialist Party with a executive presidium, a supreme people's council and a federal high court. Natural resources include oil and fish, and agricultural products are cotton, hides, skins, and coffee. In 1962 the Federation of South Arabia was formed and a treaty was signed in 1959 for independence by 1968. There was much turmoil from 1967 until 1986 when Haydar Bakr Al-Attus gained power, and there are still strong internal rivalries. The economy has been concentrated in the city of Aden, and with the loss of tourist trade in 1967, and closing of the British base, it has declined by more than 20% by 1968. Attempts are being made to build roads, fisheries, villages, a power plant, and agriculture and irrigation projects.

  13. Mineralogy and Acid-Extractable Geochemistry from the Loki's Castle Hydrothermal Field, Norwegian Sea at 74 degrees N (South Knipovich Ridge)

    NASA Astrophysics Data System (ADS)

    Barriga, F. J.; Fonseca, R.; Dias, S.; Cruz, I.; Carvalho, C.; Relvas, J. M.; Pedersen, R.

    2010-12-01

    The Loki’s Castle hydrothermal vent field was discovered in the summer of 2008 during a cruise led by the Centre of Geobiology of the University of Bergen, integrated in the H2Deep Project (Eurocores, ESF; see Pedersen et al., 2010, AGU Fall Meeting, Session OS26). Fresh volcanic glasses analyzed by EPMA are basalts. The vent site is composed of several active, over 10 m tall chimneys, producing up to 320 C fluid, at the top of a very large sulfide mound (estimated diameter 200 m). Mineralogy: The main sulfide assemblage in chimneys consists of sphalerite (Sp), pyrite (Py) and pyrrhotite, with lesser chalcopyrite (Ccp). Sulphide-poor selected samples collected at the base of chimneys are mostly composed of anhydrite (Anh), gypsum and talc (Tlc). Association of quartz, anhydrite, gypsum and barite were also found in some of the samples. The sulphide-poor samples from the base of the chimneys denote seawater interaction with the hydrothermal fluid and consequent decrease in temperature, precipitating sulfates. Sphalerite compositions are Zn(0.61-0.70)Fe(0.39-0.30)S. The variations in Fe content are consistent with those of hot, reduced hydrothermal fluids. The observed sulfide assemblage is consistent with the temperature of 320C measured in Loki’s Castle vents. Compositional zonation in sphalerites suggests different pulses of activity of the hydrothermal system, with higher contents of Zn in the center of the crystals. Geochemistry: Here we report preliminary data part of a major analytical task of sequential extraction of metals from sediments in the vicinity of Loki’s Castle, in an attempt to detect correlations with microbial populations and/or subseafloor mineralized intervals. The abundances of Cu, Pb, Ni, Cr, Zn, Fe, Mn and Co in sediments were determined by aqua regia extraction on subsamples from 7 gravity cores. Several anomalous intervals were sampled, in which Cu<707ppm, Ni shows many weak peaks (<50ppm), Cr shows 6 peaks (<121ppm), Zn shows 4 well

  14. Aboveground biomass estimation using SAR-optical (Lidar, RapidEye) and field inventory datasets in Skukuza, Kruger National Park in South Africa

    NASA Astrophysics Data System (ADS)

    Onyango Odipo, Victor; Hüttich, Christian; Luck, Wolfgang; Schmullius, Christiane

    2015-04-01

    African savanna covers approximately two-thirds of sub-saharan Africa, playing important roles as a carbon pool, habitat for mankind and wildlife, source of livelihood, an important tropical climate modifier, among other ecological roles. Sub-saharan Africa alone accounts for 25% of the tropical aboveground carbon stock (193 Gt C). Global and national level AGB estimates rely on extrapolations with regression models from few field inventories, leading in some cases, up to 100% uncertainty. Remote sensing has proven to provide reliable vegetation structural mapping, given the high spatial and temporal resolution allowing datasets to be availed in areas where ground based inventories are infeasible due to time and financial constraints. The availability of freely accessible optical remotely-sensed datasets has made this feat attainable. However, the heterogeneity of tropical savannas (co-existence of trees and grasses), coupled with erratic rainfall events and atmospheric clouds and aerosol in the tropics has made it difficult to extract biophysical properties of the savannas by solely using optical datasets. This has necessitated an assessment of synergies between active and passive remotely sensed datasets to benefit from the complementarities. In this study we assess the extent to which multi-level sub-centimeter Unmanned Aerial Vehicle (UAV) Lidar, high resolution RapidEye and microwave (ALOS PALSAR L-band and Sentinel-1 C-band) remotely sensed datasets can be used together with tree census datasets to estimate AGB within the complex southern Africa savanna ecosystem. A random forest (RF) regression model is produced which relates the Lidar canopy-height metrics (CHM) with both synthetic aperture radar (SAR) and high resolution RapidEye datasets. As a validation, we compare our results with both national and global level ABG estimates.

  15. Measurement of metal bioaccessibility in vegetables to improve human exposure assessments: field study of soil-plant-atmosphere transfers in urban areas, South China.

    PubMed

    Xiong, TianTian; Dumat, Camille; Pierart, Antoine; Shahid, Muhammad; Kang, Yuan; Li, Ning; Bertoni, Georges; Laplanche, Christophe

    2016-12-01

    The quality of cultivated consumed vegetables in relation to environmental pollution is a crucial issue for urban and peri-urban areas, which host the majority of people at the global scale. In order to evaluate the fate of metals in urban soil-plant-atmosphere systems and their consequences on human exposure, a field study was conducted at two different sites near a waste incinerator (site A) and a highway (site B). Metal concentrations were measured in the soil, settled atmospheric particulate matter (PM) and vegetables. A risk assessment was performed using both total and bioaccessible metal concentrations in vegetables. Total metal concentrations in PM were (mg kg(-1)): (site A) 417 Cr, 354 Cu, 931 Zn, 6.3 Cd and 168 Pb; (site B) 145 Cr, 444 Cu, 3289 Zn, 2.9 Cd and 396 Pb. Several total soil Cd and Pb concentrations exceeded China's Environmental Quality Standards. At both sites, there was significant metal enrichment from the atmosphere to the leafy vegetables (correlation between Pb concentrations in PM and leaves: r = 0.52, p < 0.05) which depended on the plant species. Total Cr, Cd and Pb concentrations in vegetables were therefore above or just under the maximum limit levels for foodstuffs according to Chinese and European Commission regulations. High metal bioaccessibility in the vegetables (60-79 %, with maximum value for Cd) was also observed. The bioaccessible hazard index was only above 1 for site B, due to moderate Pb and Cd pollution from the highway. In contrast, site A was considered as relatively safe for urban agriculture.

  16. Soil moisture mapping in torrential headwater catchments using a local interpolation method (Draix-Bléone field observatory, South Alps, France)

    NASA Astrophysics Data System (ADS)

    Mallet, Florian; Marc, Vincent; Douvinet, Johnny; Rossello, Philippe; Le Bouteiller, Caroline; Malet, Jean-Philippe

    2016-04-01

    Soil moisture is a key parameter that controls runoff processes at the watershed scale. It is characterized by a high area and time variability, controlled by site properties such as soil texture, topography, vegetation cover and climate. Several recent studies showed that changes in water storage was a key variable to understand the distribution of water residence time and the shape of flood's hydrograph (McDonnell and Beven, 2014; Davies and Beven, 2015). Knowledge of high frequency soil moisture variation across scales is a prerequisite for better understanding the areal distribution of runoff generation. The present study has been carried out in the torrential Draix-Bléone's experimental catchments, where water storage processes are expected to occur mainly on the first meter of soil. The 0,86 km2 Laval marly torrential watershed has a peculiar hydrological behavior during flood events with specific discharge among the highest in the world. To better understand the Laval internal behavior and to identify explanatory parameters of runoff generation, additional field equipment has been setup in sub-basins with various land use and morphological characteristics. From fall 2015 onwards this new instrumentation helped to supplement the routine measurements (rainfall rate, streamflow) and to develop a network of high frequency soil water content sensors (moisture probes, mini lysimeter). Data collected since early May and complementary measurement campaigns (itinerant soil moisture measurements, geophysical measurements) make it now possible to propose a soil water content mapping procedure. We use the LISDQS spatial extrapolation model based on a local interpolation method (Joly et. al, 2008). The interpolation is carried out from different geographical variables which are derived from a high resolution DEM (1m LIDAR) and a land cover image. Unlike conventional interpolation procedure, this method takes into account local forcing parameters such as slope, aspect

  17. THE EVOLUTION OF THE FAR-UV LUMINOSITY FUNCTION AND STAR FORMATION RATE DENSITY OF THE CHANDRA DEEP FIELD SOUTH FROM z = 0.2 TO 1.2 WITH SWIFT/UVOT

    SciTech Connect

    Hagen, Lea M. Z.; Gronwall, Caryl; Wolf, Christopher; Siegel, Michael H.; Hagen, Alex; Hoversten, Erik A.; Page, Mathew

    2015-08-01

    We use deep Swift UV/Optical Telescope (UVOT) near-ultraviolet (1600–4000 Å) imaging of the Chandra Deep Field South to measure the rest-frame far-UV (FUV; 1500 Å) luminosity function (LF) in four redshift bins between z = 0.2 and 1.2. Our sample includes 730 galaxies with u < 24.1 mag. We use two methods to construct and fit the LFs: the traditional V{sub max} method with bootstrap errors, and a maximum likelihood estimator. We observe luminosity evolution such that M* fades by ∼2 mag from z ∼ 1 to z ∼ 0.3, implying that star formation activity was substantially higher at z ∼ 1 than today. We integrate our LFs to determine the FUV luminosity densities and star formation rate densities (SFRDs) from z = 0.2 to 1.2. We find evolution consistent with an increase proportional to (1 + z){sup 1.9} out to z ∼ 1. Our luminosity densities and star formation rates are consistent with those found in the literature but are, on average, a factor of ∼2 higher than previous FUV measurements. In addition, we combine our UVOT data with the MUSYC survey to model the galaxies’ ultraviolet-to-infrared spectral energy distributions and estimate the rest-frame FUV attenuation. We find that accounting for the attenuation increases the SFRDs by ∼1 dex across all four redshift bins.

  18. Seismic response to power production at the Coso Geothermal field, south-eastern CA: using operational parameters and relocated events to study anthropogenic seismicity rates and reservoir scale tectonic structure

    NASA Astrophysics Data System (ADS)

    Lajoie, L. J.; O'Connell, D. R.; Creed, R. J.; Brodsky, E. E.

    2013-12-01

    The United States is increasing its dependence on renewable energies and with that has come an interest in expanding geothermal operations. Due to the proximity of many existing and potential geothermal sites to population centers and seismically active regions, it is important to understand how geothermal operations interact with local (and regional) seismicity, and to determine if seismicity rates are predictable from operational parameters (i.e. fluid injection, production, and net fluid extraction) alone. Furthermore, geothermal injection and production strategies can be improved by identifying, locating and characterizing related earthquakes within the tectonic related background seismicity. As the geothermal production related seismic source focal mechanisms, moment, and location are better characterized, important pragmatic questions (such as the improvement of injection strategies and 3-d thermohydromechanical model validation) and research issues (such as the relationship between far field seismic signals, local rheology changes, and native state reservoir stress evolution as a function of injection and production transients) can be more systematically addressed. We focus specifically on the 270 MW Coso geothermal field in south-eastern California, which is characterized by both high seismicity rates and relatively high aftershock triggering. After performing statistical de-clustering of local seismicity into background and aftershock rates, we show that the background rate (at both the Coso and Salton Sea geothermal fields) can be approximated during many time intervals at the 90% + confidence level by a linear combination of injection volume and the net extracted volume (difference between production and injection). Different magnitude ranges are sampled to determine if the response is constant with respect to magnitude. We also use relative relocations and focal mechanisms from Yang et al. (2012) to map fault planes within the Coso geothermal field. We

  19. The Advancement of Intraplate Tectonic Motion Detection by the Use of Atmospherically Corrected InSAR Time-series and its Decomposition into a 3D Field Vector in South-East Sicily, Italy.

    NASA Astrophysics Data System (ADS)

    Vollrath, A.; Bekaert, D. P.; Bonforte, A.; Guglielmino, F.; Hooper, A. J.; Stramondo, S.; Zucca, F.

    2014-12-01

    This study provides insights into the advancements gained by applying a tropospheric correction to a time-series InSAR small baseline network processed using the StaMPS software for the Hyblean Plateau in south-east Sicily, Italy. The contribution of the atmosphere is one of the major error sources in repeat-pass InSAR in general. For time-series analysis spatial and temporal "filtering" of the interferometric phase can be used to address atmospheric signals. This however might be at the cost of smoothing and removal of the "tectonic deformation". We applied a tropospheric correction to each interferogram based on estimates of the ERA-Interim weather model, provided by the European Center for Medium-Range Weather Forecast (ECMWF). This approach is part of the InSAR Atmospheric Correction Toolbox (Bekaert et al, in prep) and converts the tropospheric water vapor content into the phase-delay of the radar line-of-sight. For the analysis we used 49 descending and 58 ascending Envisat SAR images, which cover the time period from 2003 until 2010. In addition, we have processed 30 SAR images of RADARSAT-2 for the period between 2010-2012. Furthermore, we used the different viewing geometries and the integration of GPS data to decompose the single line-of-sight velocities into a 3-dimensional field vector by applying the SISTEM approach (Guglielmino et al. 2011). First results reveal that the atmospherically corrected data retain the deformation signal along geological structures like the Scicli-Ragusa fault whilst the standard filtering approach is canceling out these very slow deformation patterns. Simultaneously, the variability of the signal in space is diminished and thus gives more confidence on the deformation patterns observed by the SAR. Consequently, the decomposition of the line-of-sight velocities and the integration with the GPS data allows us to retrieve a more realistic deformation field.

  20. THE VLA SURVEY OF CHANDRA DEEP FIELD SOUTH. V. EVOLUTION AND LUMINOSITY FUNCTIONS OF SUB-MILLIJANSKY RADIO SOURCES AND THE ISSUE OF RADIO EMISSION IN RADIO-QUIET ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Padovani, P.; Mainieri, V.; Rosati, P.; Miller, N.; Kellermann, K. I.; Tozzi, P.

    2011-10-10

    We present the evolutionary properties and luminosity functions of the radio sources belonging to the Chandra Deep Field South Very Large Array survey, which reaches a flux density limit at 1.4 GHz of 43 {mu}Jy at the field center and redshift {approx}5 and which includes the first radio-selected complete sample of radio-quiet active galactic nuclei (AGNs). We use a new, comprehensive classification scheme based on radio, far- and near-IR, optical, and X-ray data to disentangle star-forming galaxies (SFGs) from AGNs and radio-quiet from radio-loud AGNs. We confirm our previous result that SFGs become dominant only below 0.1 mJy. The sub-millijansky radio sky turns out to be a complex mix of SFGs and radio-quiet AGNs evolving at a similar, strong rate; non-evolving low-luminosity radio galaxies; and declining radio powerful (P {approx}> 3 x 10{sup 24} W Hz{sup -1}) AGNs. Our results suggest that radio emission from radio-quiet AGNs is closely related to star formation. The detection of compact, high brightness temperature cores in several nearby radio-quiet AGNs can be explained by the coexistence of two components, one non-evolving and AGN related and one evolving and star formation related. Radio-quiet AGNs are an important class of sub-millijansky sources, accounting for {approx}30% of the sample and {approx}60% of all AGNs, and outnumbering radio-loud AGNs at {approx}< 0.1 mJy. This implies that future, large area sub-millijansky surveys, given the appropriate ancillary multiwavelength data, have the potential of being able to assemble vast samples of radio-quiet AGNs, bypassing the problems of obscuration that plague the optical and soft X-ray bands.

  1. Modeling the weekly cycle of NOx and CO emissions and their impacts on O3 in the Los Angeles-South Coast Air Basin during the CalNex 2010 field campaign

    NASA Astrophysics Data System (ADS)

    Kim, S.-W.; McDonald, B. C.; Baidar, S.; Brown, S. S.; Dube, B.; Ferrare, R. A.; Frost, G. J.; Harley, R. A.; Holloway, J. S.; Lee, H.-J.; McKeen, S. A.; Neuman, J. A.; Nowak, J. B.; Oetjen, H.; Ortega, I.; Pollack, I. B.; Roberts, J. M.; Ryerson, T. B.; Scarino, A. J.; Senff, C. J.; Thalman, R.; Trainer, M.; Volkamer, R.; Wagner, N.; Washenfelder, R. A.; Waxman, E.; Young, C. J.

    2016-02-01

    We developed a new nitrogen oxide (NOx) and carbon monoxide (CO) emission inventory for the Los Angeles-South Coast Air Basin (SoCAB) expanding the Fuel-based Inventory for motor-Vehicle Emissions and applied it in regional chemical transport modeling focused on the California Nexus of Air Quality and Climate Change (CalNex) 2010 field campaign. The weekday NOx emission over the SoCAB in 2010 is 620 t d-1, while the weekend emission is 410 t d-1. The NOx emission decrease on weekends is caused by reduced diesel truck activities. Weekday and weekend CO emissions over this region are similar: 2340 and 2180 t d-1, respectively. Previous studies reported large discrepancies between the airborne observations of NOx and CO mixing ratios and the model simulations for CalNex based on the available bottom-up emission inventories. Utilizing the newly developed emission inventory in this study, the simulated NOx and CO mixing ratios agree with the observations from the airborne and the ground-based in situ and remote sensing instruments during the field study. The simulations also reproduce the weekly cycles of these chemical species. Both the observations and the model simulations indicate that decreased NOx on weekends leads to enhanced photochemistry and increase of O3 and Ox (=O3 + NO2) in the basin. The emission inventory developed in this study can be extended to different years and other urban regions in the U.S. to study the long-term trends in O3 and its precursors with regional chemical transport models.

  2. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto regional water quality control plant in south San Francisco Bay, California: 2005

    USGS Publications Warehouse

    Cain, Daniel J.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Lorenzi, Allison H.; Moon, Edward; Shouse, Michelle K.; Hornberger, Michelle I.; Dyke, Jessica

    2006-01-01

    Trace elements in sediment and the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton 1995), clam reproductive activity and benthic, macroinvertebrate community structure are reported for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report includes data collected for the period January to December 2005, and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. Metal concentrations in both sediments and clam tissue during 2005 were consistent with results observed since 1990. Copper and zinc concentrations in sediment and bivalve tissue displayed a continued decrease over the last decade. In 2005, Cu concentrations were at or below the effects range-low (ERL) concentration (34 ?g/g) for the entire year, the first time this has been observed. Also, zinc concentrations never exceeded the ERL (150 ?g/g). Yearly average concentrations of copper, zinc and silver in Macoma petalum for 2005 were some of the lowest recorded since monitoring for metals began in 1975. The concentrations of mercury and selenium in sediments, during April and January 2004, respectively, were the highest values observed for these elements during this study. Later in 2005, concentrations decreased to historic levels. The increase in mercury and selenium in 2004 was not a permanent trend and concentrations of these elements in sediments and clams at Palo Alto remain similar to concentrations observed elsewhere in the San Francisco Bay. Analyses of the benthic-community structure of a mudflat in South San Francisco Bay over a 31-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinal clam Macoma petalum from the same area. Analysis of the

  3. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California; 2009

    USGS Publications Warehouse

    Dyke, Jessica; Parchaso, Janet K.; Thompson, Janet K.; Cain, Daniel J.; Luoma, Samuel N.; Hornberger, Michelle I.

    2010-01-01

    Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton, 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay. This report includes data collected for the period January 2009 to December 2009 and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. In 2009, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record and consistent with results observed since 1991. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations appeared to have stabilized. Annual mean concentrations have fluctuated modestly (2-4 fold) in a nondirectional manner. Data for other metals, including chromium, mercury, nickel, selenium, vanadium, and zinc, have been collected since 1994. Over this period, concentrations of these elements, which more likely reflect regional inputs and systemwide processes, have remained relatively constant, aside from typical seasonal variation that is common to all elements. Within years, the winter months (January-March) generally exhibit maximum concentrations, with a decline to annual minima in spring through fall. Mercury (Hg) in sediments and M. petalum were comparable to concentrations observed in 2008 and were generally consistent with data from previous years. Selenium (Se) concentrations in sediment varied among years and showed no sustained temporal trend. In 2009, sedimentary Se concentrations declined from the record high concentrations observed in 2008 to concentrations that were among the lowest on record. Selenium in M. petalum was unchanged from 2008

  4. Near-Field Receiving Water Monitoring of Trace Metals and a Benthic Community Near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2006

    USGS Publications Warehouse

    Lorenzi, Allison H.; Cain, Daniel J.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Hornberger, Michelle I.; Dyke, Jessica; Cervantes, Raul; Shouse, Michelle K.

    2007-01-01

    Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report includes data collected for the period January 2006 to December 2006, and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. Metal concentrations in both sediments and clam tissue during 2006 were consistent with results observed since 1990. Most notably, copper and silver concentrations in sediment and clam tissue increased in the last year but the values remain well within range of past data. Other metals such as chromium, nickel, vanadium, and zinc remained relatively constant throughout the year except for maximum values generally occurring in winter months (January-March). Mercury levels in sediment and clam tissue were some of the lowest seen on record. Conversely, selenium concentrations reached a maximum level but soon returned to baseline levels. In all, metal concentrations in sediments and tissue remain within past findings. There are no obvious directional trends (increasing or decreasing). Analyses of the benthic-community structure of a mudflat in South San Francisco Bay over a 31-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam M. petalum from the same area. Analysis of the reproductive activity of M. petalum shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable, with almost all animals

  5. Near-Field Receiving Water Monitoring of Trace Metals and a Benthic Community Near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2007

    USGS Publications Warehouse

    Lorenzi, Allison H.; Cain, Daniel J.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Hornberger, Michelle I.; Dyke, Jessica

    2008-01-01

    Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report includes data collected for the period January 2007 to December 2007, and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto?s Near-Field Receiving Water Monitoring Program, initiated in 1994. Metal concentrations in both sediments and clam tissue during 2007 remained consistent with results observed since 1990. Most notably, copper and silver concentrations in sediment and clam tissue are elevated for the second consecutive year, but the values remain well within the range of past findings. Other metals such as chromium, nickel, vanadium, and zinc remained relatively constant throughout the year except for maximum values that generally occur in winter months (January-March). Mercury levels in sediment and clam tissue were some of the lowest seen on record. Last year?s elevated selenium levels appear to be transient, and selenium concentrations have returned to background levels. Overall, metal concentrations in sediments and tissue remain within past findings. Analyses of the benthic-community structure of a mudflat in South San Francisco Bay over a 31-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the reproductive activity of M. petalum shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable, with almost all animals initiating

  6. Near-Field Receiving Water Monitoring of Trace Metals and a Benthic Community Near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2008

    USGS Publications Warehouse

    Cain, Daniel J.; Thompson, Janet K.; Dyke, Jessica; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2009-01-01

    Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton, 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay. This report includes data collected for the period January 2008 to December 2008 and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. In 2008, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record and consistent with results observed since 1991. Following significant reductions in the late 1980's, silver (Ag) and copper (Cu) concentrations appeared to have stabilized. Annual mean concentrations have fluctuated modestly (2-4 fold) in a nondirectional manner. Data for other metals, including chromium, mercury, nickel, selenium, vanadium, and zinc, have been collected since 1994. Over this period, concentrations of these elements, which more likely reflect regional inputs and systemwide processes, have remained relatively constant, aside from typical seasonal variation that is common to all elements. Within years, concentrations generally reach maximum in winter months (January-March) and decline to annual minima in spring through fall. Mercury (Hg) in sediments spiked to the highest observed level in January 2008. However, sedimentary concentrations for the rest of the year and concentrations of Hg in M. petalum for the entire year were consistent with data from previous years. Average selenium (Se) concentrations in sediment were the highest on record, but there is no evidence, yet, to suggest a temporal trend of increasing sedimentary Se. Selenium in M. petalum was not elevated relative to

  7. South Fork Latrine, oblique view showing south and east sides; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South Fork Latrine, oblique view showing south and east sides; view northwest - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  8. Characteristics of the E - and F -region field-aligned irregularities in middle latitudes: Initial results obtained from the Daejeon 40.8 MHz VHF radar in South Korea

    NASA Astrophysics Data System (ADS)

    Kwak, Young-Sil; Yang, Tae-Yong; Kil, Hoysub; Phanikumar, D.; Heo, Bok-Haeng; Lee, Jae-Jin; Hwang, Junga; Choi, Seong-Hwan; Park, Young-Deuk; Choi, Ho-Seong

    2014-03-01

    We present preliminary observations of the field-aligned-irregularities (FAIs) in the E and F regions during the solar minimum (2009 - 2010) using the 40.8 MHz coherent backscatter radar at Daejeon (36.18°N, 127.14°E, 26.7°N dip latitude) in South Korea. The radar, which consists of 24 Yagi antennas, observes the FAIs using a single beam with a peak power of 24 kW. The radar has been continuously operated since December 2009. Depending on the manner of occurrence of the backscatter echoes, the E-region echoes are largely divided into two types: quasi-periodic (QP) and continuous echoes. Our observations show that the QP echoes occur frequently above an altitude of 105 km in the post-sunset period and continuous echoes occur preferentially around an altitude of 105 km in the post-sunrise period. QP echoes appear as striated discrete echoes for a period of about 10 - 20 min. The QP-type echoes occur more frequently than the continuoustype echoes do and the echo intensity of the QP type is stronger than that of the continuous type. In the F region, the FAIs occur at night at an altitude interval of 250 - 450 km. As time proceeds, the occurrence height of the FAIs gradually increases until early in the morning and then decreases. The duration of the F-region FAIs is typically a few hours at night, although, in rare cases, FAIs persist throughout the night or appear even after sunrise. We discuss the similarities and differences of the FAIs observed by the Daejeon radar in comparison with other radar observations.

  9. The AT-LESS CO(1-0) survey of submillimetre galaxies in the Extended Chandra Deep Field South: First results on cold molecular gas in galaxies at z ˜ 2

    NASA Astrophysics Data System (ADS)

    Huynh, Minh T.; Emonts, B. H. C.; Kimball, A. E.; Seymour, N.; Smail, Ian; Swinbank, A. M.; Brandt, W. N.; Casey, C. M.; Chapman, S. C.; Dannerbauer, H.; Hodge, J. A.; Ivison, R. J.; Schinnerer, E.; Thomson, A. P.; van derWerf, P.; Wardlow, J. L.

    2017-01-01

    We present the first results from our on-going Australia Telescope Compact Array survey of 12CO(1-0) in ALMA-identified submillimetre galaxies in the Extended Chandra Deep Field South. Strong detections of 12CO(1-0) emission from two submillimetre galaxies, ALESS 122.1 (z = 2.0232) and ALESS 67.1 (z = 2.1230), were obtained. We estimate gas masses of Mgas ˜ 1.3 × 1011 M⊙ and Mgas ˜ 1.0 × 1011M⊙ for ALESS 122.1 and ALESS 67.1, respectively, adopting αCO = 1.0. Dynamical mass estimates from the kinematics of the 12CO(1-0) line yields Mdynsin 2i = (2.1 ± 1.1) × 1011 M⊙ and (3.2 ± 0.9) × 1011 M⊙ for ALESS 122.1 and ALESS 67.1, respectively. This is consistent with the total baryonic mass estimates of these two systems. We examine star formation efficiency using the LFIR versus L^' }_CO(1-0) relation for samples of local ULIRGs and LIRGs, and more distant star-forming galaxies, with 12CO(1-0) detections. We find some evidence of a shallower slope for ULIRGs and SMGs compared to less luminous systems, but a larger sample is required for definite conclusions. We determine gas-to-dust ratios of 170 ± 30 and 140 ± 30 for ALESS 122.1 and ALESS 67.1, respectively, showing ALESS 122.1 has an unusually large gas reservoir. By combining the 38.1 GHz continuum detection of ALESS 122.1 with 1.4 and 5.5 GHz data, we estimate that the free-free contribution to radio emission at 38.1 GHz is 34 ± 17 μJy, yielding a star formation rate (1400 ± 700 M⊙ yr-1) consistent with that from the infrared luminosity.

  10. Latinos in the South.

    ERIC Educational Resources Information Center

    Shaw, Emily Elliott, Ed.

    2002-01-01

    This newsletter theme issue contains five articles about the growing Latino population in the South and its impact on communities, particularly in rural areas. "Social Capital of Mexican Communities in the South" (Ruben Hernandez-Leon, Victor Zuniga) argues that, to understand and advocate for Mexican newcomer communities in the South,…

  11. New South, Old Challenges.

    ERIC Educational Resources Information Center

    Gibbs, Robert

    2001-01-01

    The South's recent rapid growth has not erased its widespread poverty and low levels of human capital. The rural South remains the nation's low-income and high-poverty region, and low education levels may limit the rural South's prospects for development. Underlying social and economic conditions that depend on and reinforce a low-skill population…

  12. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2013

    USGS Publications Warehouse

    Dyke, Jessica; Cain, Daniel J.; Thompson, Janet K.; Kleckner, Amy E.; Parcheso, Francis; Hornberger, Michelle I.; Luoma, Samuel N.

    2014-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2013 to December 2013. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2013, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se, were generally similar in timing and magnitude as those for Ag and Cu. In M. petalum, all observed elements showed annual maxima in January–February and minima in April, except for Zn, which was lowest in December. In sediments, annual maxima also occurred in January–February, and minima were measured in June and September. In 2013, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a

  13. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2011

    USGS Publications Warehouse

    Dyke, Jessica; Thompson, Janet K.; Cain, Daniel J.; Kleckner, Amy E.; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2012-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2011 to December 2011. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium, mercury, nickel, selenium, and zinc, have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2011, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Hg, Ni, Se, and Zn, were generally similar in timing and magnitude as those for Ag and Cu. In 2011, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 38-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the M. petalum community

  14. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California, 2012

    USGS Publications Warehouse

    Dyke, Jessica; Thompson, Janet K.; Cain, Daniel J.; Kleckner, Amy E.; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2013-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January to December 2012. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and in M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2012, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported for previous time periods. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se were generally similar in timing and magnitude as those for Ag and Cu. In 2012, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 39-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area

  15. Subseasonal teleconnections South America - South Africa

    NASA Astrophysics Data System (ADS)

    Grimm, Alice; Reason, Chris

    2016-04-01

    There is marked subseasonal variability over South America and southern Africa. Based on previous work showing that a teleconnection exists between the South American monsoon system and interannual summer rainfall variability over southern Africa, this study shows teleconnections between subseasonal variability over these landmasses. Observed daily gauge precipitation data for 1970-1999 are gridded to 1° resolution for South America and 2.5° for South Africa. At each grid point, anomalies of daily precipitation are calculated and submitted to a bandpass Lanczos filter to isolate subseasonal oscillations in the 20-90 day band. For each season, the filtered precipitation anomalies for the South African grid boxes are correlated with filtered precipitation anomalies in the grid boxes over South America. Lags from 0 up to 12 days are applied to the South African data, in order to investigate convection anomalies over South America that could produce atmospheric perturbations associated with South African precipitation anomalies. The significance of correlation between the filtered data takes autocorrelation into account and uses effective sample sizes. The results shown represent the best correlations for different climatic regimes such as the winter-rainfall dominated southwestern Cape, the all season rainfall South Coast and the summer-rainfall dominated Limpopo region. NCEP re-analyses are used to composite subseasonal anomalies in OLR, 200 hPa streamfunction, and vertically integrated moisture flux associated with precipitation anomaly above one standard deviation in the filtered series (positive phases) of the South African selected regions. The possible origin of the atmospheric circulation anomalies associated with those positive phases is determined using influence functions (IFs) of a vorticity equation model with a divergence source. The model is linearized about a realistic basic state and includes the divergence of the basic state and the advection of

  16. Molecular epidemiology of norovirus in South Korea.

    PubMed

    Lee, Sung-Geun; Cho, Han-Gil; Paik, Soon-Young

    2015-02-01

    Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea.

  17. South Cascade Glacier bibliography

    SciTech Connect

    Fountain, A.G.; Fulk, M.A.

    1984-01-01

    South Cascade Glacier, in Washington State, resides in a well-defined basin with mainly unglacierized divides making it ideal for most glaciological and hydrological studies. This bibliography is divided into three cateogories: (1) studies done about South Cascade Glacier specifically; (2) studies that use data from South Cascade Glacier but do not focus on or give insight to the glacier itself; and (3) instrumentation studies and non-glacier projects including snow studies done in the basin. (ACR)

  18. Terrorism in South Korea.

    PubMed

    Wang, Soon Joo; Choi, Jin Tae; Arnold, Jeffrey

    2003-01-01

    South Korea has experienced > 30 suspected terrorism-related events since 1958, including attacks against South Korean citizens in foreign countries. The most common types of terrorism used have included bombings, shootings, hijackings, and kidnappings. Prior to 1990, North Korea was responsible for almost all terrorism-related events inside of South Korea, including multiple assassination attempts on its presidents, regular kidnappings of South Korean fisherman, and several high-profile bombings. Since 1990, most of the terrorist attacks against South Korean citizens have occurred abroad and have been related to the emerging worldwide pattern of terrorism by international terrorist organizations or deranged individuals. The 1988 Seoul Olympic Games provided a major stimulus for South Korea to develop a national emergency response system for terrorism-related events based on the participation of multiple ministries. The 11 September 2001 World Trade Center and Pentagon attacks and the 2001 United States of America (US) anthrax letter attacks prompted South Korea to organize a new national system of emergency response for terrorism-related events. The system is based on five divisions for the response to specific types of terrorist events, involving conventional terrorism, bioterrorism, chemical terrorism, radiological terrorism, and cyber-terrorism. No terrorism-related events occurred during the 2002 World Cup and Asian Games held in South Korea. The emergency management of terrorism-related events in South Korea is adapting to the changing risk of terrorism in the new century.

  19. Estimation of resistance allele frequency to maize incorporated Bacillus thuringiensis Cry2Ab2 protein in field populations of the fall army Spodoptera frugiperda (Lepidoptera: Noctuidae) from south region of the United State

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target of transgenic maize and cotton expressing Bacillus thuringiensis (Bt) proteins in both North and South Americas. In the falls of 2013 and 2014, a total of 215 F2 two-parent families of S. frugiperda were es...

  20. Evaluation of a SNP-based qPCR identification system for the Ug99 race group using field collections of Puccinia graminis f. sp. tritici in South Africa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual surveys aim to monitor the distribution and composition of the local stem rust population within South Africa. The number of isolates that are processed is limited due to physical and financial constraints and the problem of non-viable spores. An accurate DNA based identification method would...

  1. Neuropsychology in South Africa.

    PubMed

    Truter, Sharon; Mazabow, Menachem; Morlett Paredes, Alejandra; Rivera, Diego; Arango-Lasprilla, Juan Carlos

    2017-03-21

    This survey forms part of an international research study conducted in 39 countries and is the first to describe the characteristics of individuals engaged in the practice of neuropsychology in South Africa (SA). The purpose was to analyze the characteristics of individuals working in the profession of neuropsychology in order to understand their background, professional training, current work situation, assessment and diagnostic procedures, rehabilitation techniques, teaching responsibilities, and research activities. Ninety-five professionals working in neuropsychology completed an online survey between July and November 2015. The majority of participants were female and the mean age was 46.97 years. The majority of professions working in neuropsychology have a background in psychology, with additional specialized training and supervised clinical practice. Over half work in private practice and are on average satisfied with their work. Participants identified as clinicians primarily work with TBI and ADHD individuals. The main limitation for the use of neuropsychological instruments is the lack of normative data in SA and the main barrier to the field is the lack of academic training programs. There is a need to improve graduate curriculums, enhance existing clinical training, develop professional certification programs, validate existing neuropsychological tests, and create new, culturally relevant instruments.

  2. The South Pole Telescope

    SciTech Connect

    Ruhl, J.E.; Ade, P.A.R.; Carlstrom, J.E.; Cho, H.M.; Crawford,T.; Dobbs, M.; Greer, C.H.; Halverson, N.W.; Holzapfel, W.L.; Lanting,T.M.; Lee, A.T.; Leitch, E.M.; Leong, J.; Lu, W.; Lueker, M.; Mehl, J.; Meyer, S.S.; Mohr, J.J.; Padin, S.; Plagge, T.; Pryke, C.; Runyan, M.C.; Schwan, D.; Sharp, M.K.; Spieler, H.; Staniszewski, Z.; Stark, A.A.

    2004-11-04

    A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10 m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency-multiplexed readouts. The first key project will be to conduct a survey over 4000 degrees for galaxy clusters using the Sunyaev-Zeldovich Effect. This survey should find many thousands of clusters with a mass selection criteria that is remarkably uniform with redshift. Armed with redshifts obtained from optical and infrared follow-up observations, it is expected that the survey will enable significant constraints to be placed on the equation of state of the dark energy.

  3. Diversity and origin of South African chickens.

    PubMed

    Mtileni, B J; Muchadeyi, F C; Maiwashe, A; Chimonyo, M; Groeneveld, E; Weigend, S; Dzama, K

    2011-10-01

    The objectives of this study were to analyze the genetic diversity and structure of South African conserved and field chicken populations and to investigate the maternal lineages of these chicken populations. Four South African conserved chicken populations (n = 89), namely, Venda (VD_C), Ovambo, Naked Neck, and Potchefstroom Koekoek from the Animal Production Institute of the Agricultural Research Council, and 2 field populations, the Venda and Ovambo (OV_F), from which the Ovambo and the Venda conservation flocks were assumed to have been sampled, were genotyped for 460 bp of the mitochondrial DNA (mtDNA) D-loop sequence. Haplotypes of these chickens were aligned to 7 Japanese and 9 Chinese and Eurasian chicken mtDNA D-loop sequences taken from GenBank and reflecting populations from presumed centers of domestication. Sequence analysis revealed 48 polymorphic sites that defined 13 haplotypes in the South African chicken populations. All 6 South African conserved and field chicken populations observed were found to be polymorphic, with the number of haplotypes ranging from 3 for VD_C to 8 for OV_F. The lowest haplotype diversity, 0.54 ± 0.08, was observed in VD_C chickens, whereas the highest value, 0.88 ± 0.05, was observed in OV_F chickens. Genetic diversity between the 4 South African conserved and 2 field chicken populations constituted 12.34% of the total genetic variation, whereas within-population diversity constituted 87.66% of the total variation. The median network analysis of the mtDNA D-loop haplotypes observed in the South African conserved and field populations and the reference set resulted in 5 main clades. All 6 South African chickens were equally represented in the major clade, E, which is presumed to be of Indian subcontinent maternal origin and may have its roots in Southeast Asia. The results showed multiple maternal lineages of South African chickens. Conservation flocks and field chicken populations shared the major haplotypes A, D and E

  4. 118. Stage basement. View, facing south, of the south hydraulic ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    118. Stage basement. View, facing south, of the south hydraulic ram (type D) in the middle row. Photo was taken before the stage flooring was removed. - Auditorium Building, 430 South Michigan Avenue, Chicago, Cook County, IL

  5. 10. BUILDING: SECOND FLOOR (East Section), VIEW SOUTH: EAST, SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. BUILDING: SECOND FLOOR (East Section), VIEW SOUTH: EAST, SOUTH AND WEST WALLS OF COLD STORAGE, ALSO SHOWING REMNANTS OF COOLING PIPES - Boston Beer Company, 225-249 West Second Street, South Boston, Suffolk County, MA

  6. 3. SOUTH SIDE. Edwards Air Force Base, South Base ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. SOUTH SIDE. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  7. 9. West elevation, west end of south wing wall, south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. West elevation, west end of south wing wall, south abutment and south railing panel looking east - Western Maryland Railway Bridge, Spanning Maryland Route 51 at Spring Gap, Cumberland, Allegany County, MD

  8. Curbing stem cell tourism in South Africa.

    PubMed

    Meissner-Roloff, Madelein; Pepper, Michael S

    2013-12-01

    Stem cells have received much attention globally due in part to the immense therapeutic potential they harbor. Unfortunately, malpractice and exploitation (financial and emotional) of vulnerable patients have also drawn attention to this field as a result of the detrimental consequences experienced by some individuals that have undergone unproven stem cell therapies. South Africa has had limited exposure to stem cells and their applications and, while any exploitation is detrimental to the field of stem cells, South Africa is particularly vulnerable in this regard. The current absence of adequate legislation and the inability to enforce existing legislation, coupled to the sea of misinformation available on the Internet could lead to an increase in illegitimate stem cell practices in South Africa. Circumstances are already precarious because of a lack of understanding of concepts involved in stem cell applications. What is more, credible and easily accessible information is not available to the public. This in turn cultivates fears born out of existing superstitions, cultural beliefs, rituals and practices. Certain cultural or religious concerns could potentially hinder the effective application of stem cell therapies in South Africa and novel ways of addressing these concerns are necessary. Understanding how scientific progress and its implementation will affect each individual and, consequently, the community, will be of cardinal importance to the success of the fields of stem cell therapy and regenerative medicine in South Africa. A failure to understand the ethical, cultural or moral ramifications when new scientific concepts are introduced could hinder the efficacy and speed of bringing discoveries to the patient. Neglecting proper procedure for establishing the field would lead to long delays in gaining public support in South Africa. Understanding the dangers of stem cell tourism - where vulnerable patients are subjected to unproven stem cell therapies that

  9. Heart Failure in South Asia

    PubMed Central

    Sivadasan Pillai, Harikrishnan; Ganapathi, Sanjay

    2013-01-01

    South Asia (SA) is both the most populous and the most densely populated geographical region in the world. The countries in this region are undergoing epidemiological transition and are facing the double burden of infectious and non-communicable diseases. Heart failure (HF) is a major and increasing burden all over the world. In this review, we discuss the epidemiology of HF in SA today and its impact in the health system of the countries in the region. There are no reliable estimates of incidence and prevalence of HF (heart failure) from this region. The prevalence of HF which is predominantly a disease of the elderly is likely to rise in this region due to the growing age of the population. Patients admitted with HF in the SA region are relatively younger than their western counterparts. The etiology of HF in this region is also different from the western world. Untreated congenital heart disease and rheumatic heart disease still contribute significantly to the burden of HF in this region. Due to epidemiological transition, the prevalence of hypertension, diabetes mellitus, obesity and smoking is on the rise in this region. This is likely to escalate the prevalence of HF in South Asia. We also discuss potential developments in the field of HF management likely to occur in the nations in South Asia. Finally, we discuss the interventions for prevention of HF in this region PMID:23597297

  10. New ilarvirus species in south Florida tomatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato necrotic streak virus (TomNSV) is a novel ilarvirus discovered infecting tomatoes in south Florida starting in fall 2013. It was found during surveys of vegetable fields for Tomato spotted wilt virus, Groundnut ringspot virus and Tomato chlorotic spot virus because all four viruses induce sim...

  11. South Atlantic Anomaly

    Atmospheric Science Data Center

    2013-04-19

    article title:  The South Atlantic Anomaly     View larger GIF image The South Atlantic Anomaly (SAA) . Even before the cover opened, the Multi-angle Imaging ... Atlantic Anomaly location:  Atlantic Ocean Global Images First Light Images region:  Before the ...

  12. South Africa's Constitutional Change.

    ERIC Educational Resources Information Center

    Getman, Thomas

    1987-01-01

    Describes the striking dichotomy of South Africa's beauty and the squalor resulting from the apartheid policies of the government. Reviews reactions of black South Africans to recent constitutional changes and details efforts to secure more sweeping reform. Includes stories of several individuals who have taken actions which oppose the system of…

  13. Language in South Africa.

    ERIC Educational Resources Information Center

    Mesthrie, Rajend, Ed.

    This collection of 24 papers focuses on language and society in South Africa. Part 1, "The Main Language Groupings," includes (1) "South Africa: A Sociolinguistic Overview" (R. Mesthrie); (2) "The Khoesan Languages" (A. Traill); (3) "The Bantu Languages: Sociohistorical Perspectives" (Robert K. Herbert and…

  14. Huntsville South Side Square

    NASA Technical Reports Server (NTRS)

    1940-01-01

    This 1940s photo of the South side of Square in downtown Huntsville, Alabama, looking west, shows a historical bank in the background with cars parked just South of the Courthouse (not shown in photo). (Courtesy of Huntsville/Madison County Public Library)

  15. VIEW SOUTH, NORTH ELEVATION OF (FROM LEFT) ENGINE HOUSE, BELT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW SOUTH, NORTH ELEVATION OF (FROM LEFT) ENGINE HOUSE, BELT SHED, ECCENTRIC HOUSE, NOTE ROD LINES EXITING ECCENTRIC HOUSE. - Golden Oil Company, Lot 410 Lease, Sheffield Field, Donaldson, Warren County, PA

  16. VIEW NORTH, SOUTH ELEVATION OF (FROM LEFT) ECCENTRIC HOUSE, BELT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW NORTH, SOUTH ELEVATION OF (FROM LEFT) ECCENTRIC HOUSE, BELT SHED, AND ENGINE HOUSE, NOTE EXHAUST LOWER RIGHT OF ENGINE HOUSE. - Golden Oil Company, Lot 410 Lease, Sheffield Field, Donaldson, Warren County, PA

  17. 2. AERIAL SHOT HANGARS 14 (IN CENTER OF VIEW), SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. AERIAL SHOT HANGARS 1-4 (IN CENTER OF VIEW), SOUTH AND WEST FACING SIDES. BUILDING 238 IS IN LOWER RIGHT FOREGROUND. - Hill Field, Airplane Repair Hangars No. 1-No. 4, 5875 Southgate Avenue, Layton, Davis County, UT

  18. General view looking toward the roulette farm cluster from south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view looking toward the roulette farm cluster from south to north; note the present-day field was an orchard at the time of the battle - Roulette Farm, House, Sharpsburg, Washington County, MD

  19. Perspective of Bright Angel stone vault, view south, with HAER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Perspective of Bright Angel stone vault, view south, with HAER field team measuring (Michael Lee and Dominic Duran foreground, Christopher Marston rear). - Grand Canyon Village Utilities, Grand Canyon National Park, Grand Canyon Village, Coconino County, AZ

  20. Looking south towards building 215. Fuel pipelines are under this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking south towards building 215. Fuel pipelines are under this field. - Fitzsimons General Hospital, Underground Fuel Pipelines, North Page Street North of Building No. 215, Aurora, Adams County, CO

  1. South Africa, Namibia Diamond Deposits

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This radar image covers a portion of the Richtersveld National Park and Orange River (top of image) in the Northern Cape Province of the Republic of South Africa. The Orange River marks the boundary between South Africa to the south and Namibia to the north. This is an area of active mining for diamonds, which were washed downstream from the famous Kimberley Diamond Area, millions of years ago when the river was much larger. The mining is focused on ancient drainages of the Orange River which are currently buried by think layers of sand and gravel. Scientists are investigating whether these ancient drainages can be seen with the radar's ability to penetrate sand cover in extremely dry regions. A mine, shown in yellow, is on the southern bank of the river in an abandoned bend which is known as an 'oxbow.' The small bright circular areas (left edge of image) west of the mine circles are fields of a large ostrich farm that are being watered with pivot irrigation. The large dark area in the center of the image is the Kubus Pluton, a body of granite rock that broke through the surrounding rocks about 550 million years ago. North is toward the upper right. The area shown is about 55 by 60 kilometers (34 by 37 miles) centered at 28.4 degrees south latitude, 16.8 degrees east longitude. Colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; blue is C-band horizontally transmitted and vertically received. The image was acquired on April 18, 1994 by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar when it flew aboard the space shuttle Endeavour. SIR-C/X-SAR is a joint mission of the U.S./German and Italian space agencies.

  2. View of South TwentySixth Street looking towards Cutting Boulevard at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of South Twenty-Sixth Street looking towards Cutting Boulevard at center distance. Sports field on left, Building Nos. 35 & 36 on right and right rear, looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  3. View of intersection of Foothill Avenue and South TwentySixth Street. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of intersection of Foothill Avenue and South Twenty-Sixth Street. Note sports field at center rear. Seen from Foothill Avenue at Parking Area No. 34, looking southwest - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  4. Neosporosis in South America.

    PubMed

    Moore, D P

    2005-01-20

    This work gathers reports about Neospora-infections in South America. Neospora-infections have been reported from Argentina, Brazil, Chile, Paraguay, Peru and Uruguay. Evidence of exposure to N. caninum was mentioned in cattle, goats, sheep, dogs, cats, water buffaloes, alpacas, llamas, South American opossums, wolves and other wild canids. No antibodies were found in horses. Interesting epidemiological and pathological data were described. Two isolations were performed from dogs, one from cattle, and recently five from water buffaloes. Since the cattle industry is important in South America and reproductive losses caused by Neospora-infection have been identified, more investigations are needed in order to understand its epidemiology and control the disease.

  5. View looking south out the door opening from the south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View looking south out the door opening from the south side of the rotunda extension onto the "dog house" or vestibule positioned where the west Verandah of the south wing turns ninety degrees and continues along the south wall of the central pavilion. - U. S. Naval Asylum, Biddle Hall, Gray's Ferry Avenue, Philadelphia, Philadelphia County, PA

  6. Mercury's South Polar Region

    NASA Video Gallery

    This animation shows 89 wide-angle camera (WAC) images of Mercury’s south polar region acquired by the Mercury Dual Imaging System (MDIS) over one complete Mercury solar day (176 Earth days). Thi...

  7. Ladybugs of South Dakota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Images of the 79 species of Coccinellidae occurring in South Dakota are presented in taxonomic order. Information on each species includes genus-species name, sub-familial classification, and lengths and widths....

  8. Lunar South Pole Illumination

    NASA Video Gallery

    Simulated illumination conditions over the lunar South Pole region, from ~80°S to the pole. The movie runs for 28 days, centered on the LCROSS impact date on October 9th, 2009. The illumination ca...

  9. How the structure of a continental margin affects the development of a fold and thrust belt. 3: evidences from field mapping and geological cross-sections in south-central Taiwan

    NASA Astrophysics Data System (ADS)

    Alvarez-Marron, Joaquina; Biete, Cristina; Brown, Dennis; Camanni, Giovanni; Kuo-Chen, Hao; Ho, Chun-Wei

    2016-04-01

    The Eurasian Margin is obliquely colliding with the Luzon Arc to form the Taiwan orogen. This configuration is particularly apparent in south-central part of the island providing a case example to investigate the effects of structural inheritance in the development of the thrust and fold belt. The Eurasian Margin evolved from a pre-Cenozoic continental basement that underwent rifting in the Early Eocene and subsequent sea-floor spreading to form the South China Sea during the late Early Oligocene. The margin underwent localized extension in the Middle Miocene, before the initiation of collision with the Luzon Arc by the Early Miocene. The important along-strike changes in structure and topography of south-central Taiwan thrust and fold belt are evidenced in the detailed geological map and 3 balanced geological cross sections. A 3D tomography model is integrated in this study to help constrain the structure at depth. Major along-strike changes seem to be related to structures oriented at a high angle to the thrust system. These include changes in strike of thrusts and fold traces, the changing elevation of thrusts and stratigraphic contacts, and the growing importance of Middle Miocene sediments within the thrust system that take place from north to south. Horizontal slices of the tomography model illustrate that N-S changes in velocity have the orientation of the inherited structural grain of the Eurasian margin. In particular, the inherited location of the Mesozoic margin's shelf-slope transition affects the distribution of seismicity and the location of lateral stratigraphic and structural changes. Also, it appears to be associated with the inversion of Eocene- and Miocene-age extensional faults, deeply rooted in the pre-Cenozoic basement that trend oblique to the thrust belt. The inversion of inherited structures affects the uplift of Miocene syn-extensional and syn-tectonic Plio-Pleistocene foreland basin sediments, and of the pre-Cenozoic basement. Section A

  10. Weed Identification Field Training Demonstrations.

    ERIC Educational Resources Information Center

    Murdock, Edward C.; And Others

    1986-01-01

    Reviews efforts undertaken in weed identification field training sessions for agriprofessionals in South Carolina. Data over a four year period (1980-1983) revealed that participants showed significant improvement in their ability to identify weeds. Reaffirms the value of the field demonstration technique. (ML)

  11. South Pole Lorentz Invariance Test

    NASA Astrophysics Data System (ADS)

    Hedges, Morgan; Smiciklas, Marc; Romalis, Michael

    2015-04-01

    Tests of Lorentz and CPT symmetries are important because they form a cornerstone of quantum field theory and general relativity. To test one of the consequences of local Lorentz invariance we have performed a precision test of spatial isotropy at the Amundsen-Scott station near the geographic South Pole. This location provides the most isotropic environment available on Earth. We use an atomic spin co-magnetometer to compare energy levels in 21 Ne and Rubidium atoms as the apparatus rotates with respect to the cosmos. Our experimental sensitivity is more than an order of magnitude greater than in previous such measurements, known as Hughes-Drever experiments. By operating at the South Pole we eliminate background signals due to the gyroscopic interactions of spins with Earth's rotation as well as diurnal environmental effects. The experiment has finished a 2-year data collection period and we expect to present the final results at the meeting. This is the first precision atomic physics experiment performed at the Pole and we will discuss the potential for future such measurements.

  12. Anaglyph, South America

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This anaglyph (stereoscopic view) of South America was generated with data from the Shuttle Radar Topography Mission (SRTM). It is best viewed at or near full resolution with anaglyph glasses. For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south but variable east-west), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the South American continent is readily apparent.

    Topographic relief in South America is dominated by the Andes Mountains, which extend all along the Pacific Coast. These mountains are created primarily by the convergence of the Nazca and South American tectonic plates. The Nazca Plate, which underlies the eastern Pacific Ocean, slides under western South America resulting in crustal thickening, uplift, and volcanism. Another zone of plate convergence occurs along the northwestern coast of South America where the Caribbean Plate also slides under the South American Plate and forms the northeastern extension of the Andes Mountains.

    East of the Andes, much of northern South America drains into the Amazon River, the world's largest river in terms of both watershed area and flow volume. Topographic relief is very low in much of the Amazon Basin but SRTM data provide an excellent detailed look at the basin's three-dimensional drainage pattern, including the geologic structural trough (syncline) that hosts the eastern river channel.

    North of the Amazon, the Guiana Highlands commonly stand in sharp contrast to the surrounding lowlands, indeed hosting the world's tallest waterfall, Angel Falls (979 meters or 3212 feet). Folded and fractured bedrock structures are distinctive in the topographic pattern.

    South of the Amazon, the Brazilian

  13. South China Sea

    USGS Publications Warehouse

    Morton, Brian; Blackmore, Graham

    2001-01-01

    The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshop and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km2 and depths range from the shallowest coastal fringe to 5377 m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economies on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of the three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken on the South

  14. South China Sea.

    PubMed

    Morton, B; Blackmore, G

    2001-12-01

    The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshop and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km2 and depths range from the shallowest coastal fringe to 5377 m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economies on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global total of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken on the

  15. View of sports field from Easter Hill looking at intersection ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of sports field from Easter Hill looking at intersection of South Twenty-Sixth Street and Foothill Avenue at left center rear. Buildings No. 36, 35, 25, 27, and 29, from left to right. Looking northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  16. View of baseball back stop on sports field at intersection ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of baseball back stop on sports field at intersection of South Twenty-Sixth Street and Foothill Avenue. Buildings No. 36, 37, 38, and 35, from to right. Foothill Avenue at center rear. Looking east-northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  17. Biotechnology in South Africa.

    PubMed

    Cloete, Thomas E; Nel, Louis H; Theron, Jacques

    2006-12-01

    Since adopting the National Biotechnology Strategy in 2001, the South African government has established several regional innovation centres and has put in place initiatives to encourage international partnerships that can spur internal development of life science ventures. This strategy seeks to capitalize on the high quality of research carried out in public research institutions and universities but is hampered, somewhat, by the lack of entrepreneurial culture among South African researchers due to, among other reasons, the expenses involved in registering foreign patents. Although private sector development is still relatively embryonic, start-ups are spinning out of universities and pre-existing companies. These represent a vital source of innovations for commercialization in the future, provided that the challenges facing the emerging South African biotechnology industry can be overcome.

  18. Geomagnetic observations on tristan da cunha, south atlantic ocean

    USGS Publications Warehouse

    Matzka, J.; Olsen, N.; Maule, C.F.; Pedersen, L.W.; Berarducci, A.M.; Macmillan, S.

    2009-01-01

    Few geomagnetic ground observations exist of the Earth's strongest core field anomaly, the South Atlantic Anomaly (SAA). The geomagnetic repeat station on the island Tristan da Cunha, located half-way between South Africa and South America at 37?? 05' S, 12?? 18' W, is therefore of crucial importance. We have conducted several sets of repeat station measurements during magnetically quiet conditions (Kp 2o or less) in 2004. The procedures are described and the results are compared to those from earlier campaigns and to the predictions of various global field models. Features of the local crustal bias field and the solar quiet daily variation are discussed. We also evaluate the benefit of continuous magnetic field recordings from Tristan da Cunha, and argue that such a data set is a very valuable addition to geomagnetic satellite data. Recently, funds were set up to establish and operate a magnetometer station on Tristan da Cunha during the Swarm magnetic satellite mission (2011-2014).

  19. Magnetic fabric results from DSDP Holes 380A (Black Sea) and 524 (South Atlantic) sediment cores: A case study for the comparison between low and high field torque magnetometer measurements

    NASA Astrophysics Data System (ADS)

    Folami, S. L.; Hailwood, E. A.

    1991-08-01

    Magnetic fabric (anisotropy) measurements have been made on samples of Quaternary sediments from DSDP Hole 380A (Black Sea) and Tertiary and Cretaceous nannofossil oozes, marls and volcanoclastic sandstones from the Southeast flank of the Walvis Ridge at Hole 524, recovered during Legs 42B and 73 of the International Program of Ocean Drilling (IPOD). The fabric was determined by means of both a low field and a high field torque magnetometer. The overall results from the low field measurements are similar to those from the high field measurements. The results from both sets of measurements indicate the existence of a NE-SW lineation at Hole 380A and a NW-SE lineation at Hole 524. For Hole 380A some of the individual parameters show slight differences in values for the low field and high field torque measurements while for Hole 524 these individual parameters compare favourably and indicate an approximately one-to-one correspondence. In general the fabric is better defined at Hole 524 than at Hole 380A. Anisotropy measurements sometimes were found to be greatly affected by the shape of the sample. This apparent ‘shape-effect’ appears to be more prevalent in the high field than in the low field measurements. In addition, for Holes 380A and 524 some samples show deformational-style fabric characteristics on one instrument and depositional-style characteristics on the other. The reasons for these differences and how the effects on the anisotropy data can be removed or minimised are described in this paper.

  20. Agriculture, Rio Sao Francisco, Brazil, South America

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The large field patterns in this view of the Rio Sao Francisco basin, Brazil, South America, (11.5S, 43.5W) indicate a commercial agriculture venture; family subsistence farms are much smaller and laid out in different patterns. Land clearing in Brazil has increased at an alarming rate in recent years and preliminary estimates suggest a 25 to 30% increase in deforestation since 1984. The long term impact on the ecological processes are still unknown.

  1. 170. GWMP SOUTH OF GREAT HUNTING CREEK LOOKING SOUTH. (NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    170. GWMP SOUTH OF GREAT HUNTING CREEK LOOKING SOUTH. (NOTE ASPHALT PAVEMENT AND FILLED LAND) - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  2. View of south grounds, from west entrance, looking south towards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of south grounds, from west entrance, looking south towards Wilshire Blvd. - National Home for Disabled Volunteer Soldiers, Pacific Branch, 11301 Wilshire Boulevard, Los Angeles, Los Angeles County, CA

  3. 22. VIEW SOUTH, INTERIOR OF SOUTH PIT, SHOWING FINAL STEP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. VIEW SOUTH, INTERIOR OF SOUTH PIT, SHOWING FINAL STEP IN GEARING THAT DRIVES OPERATING WHEEL, WITH HYDRAULIC SHAFT BRAKE - Mystic River Bridge, Spanning Mystic River at U.S. Route 1, Groton, New London County, CT

  4. 18. WEST PART OF SOUTH SIDE OF SOUTH WING AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. WEST PART OF SOUTH SIDE OF SOUTH WING AND PART OF REAR OF FRONT (WEST) PORTION OF BUILDING, LOOKING NORTHWEST (Harms) - Dairy Industry Building, Iowa State University campus, Ames, Story County, IA

  5. INTERIOR FOURTH FLOOR, SOUTH HALF, LOOKING SOUTH. NOTE MUSHROOM COLUMNS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR FOURTH FLOOR, SOUTH HALF, LOOKING SOUTH. NOTE MUSHROOM COLUMNS AND CEILING HAS WOODEN NAILERS. - Colt Fire Arms Company, North Armory, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

  6. South Bedroom Mantel Profile, South Bedroom Fireplace Details, Front Stair ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South Bedroom Mantel Profile, South Bedroom Fireplace Details, Front Stair Bracket, Attic Door Jamb and Door Profile - National Home for Disabled Volunteer Soldiers - Battle Mountain Sanitarium, Governor's Quarters, 500 North Fifth Street, Hot Springs, Fall River County, SD

  7. 9. VIEW TO NORTH; SOUTH RETAINING WALL AND SOUTH FACADE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW TO NORTH; SOUTH RETAINING WALL AND SOUTH FACADE OF MBE BUILDING (Asano) - Los Angeles Union Passenger Terminal, Mail, Baggage, & Express Building, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  8. 14. South room first floor. View looking south. East porch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. South room first floor. View looking south. East porch visible through window. - Fort Hill Farm, Mansion, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  9. 13. South room first floor. View looking southwest. South addition ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. South room first floor. View looking southwest. South addition visible through doorway. - Fort Hill Farm, Mansion, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  10. 1. WEST AND SOUTH SIDES, FROM APPROXIMATELY 25 FEET SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. WEST AND SOUTH SIDES, FROM APPROXIMATELY 25 FEET SOUTH OF SOUTHEASTERN CORNER OF BUILDING 441-B, LOOKING NORTHEAST. - Oakland Naval Supply Center, Heating Plant, On Northwest Corner of K Street & Fifth Street, Oakland, Alameda County, CA

  11. Interior planar view of south wall, view towards the south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior planar view of south wall, view towards the south southeast with scale - Fort McClellan Ammunition Storage Area, Building No. 4404, Second Avenue (Magazine Road), Anniston, Calhoun County, AL

  12. 5. Mispillion Lighthouse, South Elevation Mispillion Lighthouse, South bank ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Mispillion Lighthouse, South Elevation - Mispillion Lighthouse, South bank of Mispillion River at its confluence with Delaware River at northeast end of County Road 203, 7 miles east of Milford, Milford, Sussex County, DE

  13. DETAIL VIEW, OXEYE WINDOW, SOUTH WALL OF SOUTH GARRET. THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW, OX-EYE WINDOW, SOUTH WALL OF SOUTH GARRET. THE MUNTIN PATTERN USED IN THIS WINDOW WAS REFERRED TO AS “GOTHIC” IN THE EIGHTEENTH CENTURY - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  14. 7. SOUTH ELEVATION OF BUILDING 262 (SOUTH SENTRY POST) IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. SOUTH ELEVATION OF BUILDING 262 (SOUTH SENTRY POST) IN STORAGE AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  15. Looking South at south End of Green Room Including Scrubber ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking South at south End of Green Room Including Scrubber for Incinerator within Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

  16. 64. Credit JTL. West and south elevations from across South ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    64. Credit JTL. West and south elevations from across South Battle Creek. Note penstock descending hill in background and new powerhouse construction in foreground. - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  17. 27. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, SOUTH LOBBY, DETAIL OF BRONZE SEAL IN FLOOR (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  18. View of south entrance to #157 through south breezeway arches ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of south entrance to #157 through south breezeway arches - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  19. Detail of south wing south elevation wall section; camera facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of south wing south elevation wall section; camera facing northwest - Mare Island Naval Shipyard, Defense Electronics Equipment Operating Center, I Street, terminus west of Cedar Avenue, Vallejo, Solano County, CA

  20. Assessment of undiscovered petroleum resources in Central and South America

    USGS Publications Warehouse

    Schenk, C.J.

    2002-01-01

    The USGS has assessed undiscovered conventional oil and gas resources in 128 selected petroleum provinces of the world. Of these 128 provinces, 23 are in South America, Central America, and the Caribbean area. In the USGS 2000 Assessment, the provinces resulted in mean totals for undiscovered resource of 105 billion bbl of oil and 487 tcf of gas. The potential for giant oil and gas fields is greatest in the basins along the Atlantic margin of eastern South America, from the Santos Basin in the south to the Guyana-Suriname Basin in the north. The potential for giant fields is mainly offshore, in water depths up to 3600 m. The South and Central America region ranks third in the world for undiscovered conventional oil and gas behind the Middle East and the Former Soviet Union.

  1. South Polar Cap

    NASA Technical Reports Server (NTRS)

    2005-01-01

    8 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows landforms created by sublimation processes on the south polar residual cap of Mars. The bulk of the ice in the south polar residual cap is frozen carbon dioxide.

    Location near: 86.6oS, 342.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  2. 23. View of west side of South Coweta Avenue south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. View of west side of South Coweta Avenue south of East Ward Street, facing west. - Gaskin Avenue Neighborhood, Bounded by Dart Street to east, CSX Railroad to south, Pearl & Madison Avenues to west, & Wilson & Gordon Streets to north, Douglas, Coffee County, GA

  3. 7. DETAIL, LOOKING SOUTH, INTERIOR OF SOUTH ARCH, SHOWING DRAINAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL, LOOKING SOUTH, INTERIOR OF SOUTH ARCH, SHOWING DRAINAGE HOLE IN THE WEST END OF THE SOUTH WALL AND VERTICAL QUARRY DRILLING HOLES ON THE STONE FACE - Mulladay Hollow Bridge, Spanning Mulladay Hollow Creek at County Road No.61, Eureka Springs, Carroll County, AR

  4. 24. View of west side of South Coweta Avenue south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. View of west side of South Coweta Avenue south of East Ward Street, facing northwest. - Gaskin Avenue Neighborhood, Bounded by Dart Street to east, CSX Railroad to south, Pearl & Madison Avenues to west, & Wilson & Gordon Streets to north, Douglas, Coffee County, GA

  5. South portal and deck view from south, showing inclined endposts, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South portal and deck view from south, showing inclined endposts, Pratt through trusses, south portal strut, overhead bracing, pipe rails and posts, and concrete deck with bituminous wearing surface - Castle Garden Bridge, Township Route 343 over Bennetts Branch of Sinnemahoning Creek, Driftwood, Cameron County, PA

  6. Anglicising Postapartheid South Africa

    ERIC Educational Resources Information Center

    Louw, P. Eric

    2004-01-01

    The apartheid state deliberately encouraged linguistic diversity and actively built cultural infrastructures which impeded Anglicisation. With the end of apartheid has come "de facto" Anglicisation. So although South Africa has, since 1994, had 11 official languages, in reality, English is swamping the other 10 languages. Afrikaans has,…

  7. Workforce Brief: South Dakota

    ERIC Educational Resources Information Center

    Western Interstate Commission for Higher Education, 2006

    2006-01-01

    In South Dakota, the demand for well-educated employees will only increase over the next several years. In the decade leading up to 2012, healthcare and healthcare support occupations will see growth of about 25 percent; over 2,500 new practitioners and technicians will be needed. There will be a 24 percent increase in the number of…

  8. SOUTH WARNER WILDERNESS, CALIFORNIA.

    USGS Publications Warehouse

    Duffield, Wendell A.; Weldin, Robert E.

    1984-01-01

    A mineral appraisal utilized geologic, geochemical, and geophysical data and an examination of mining claims in the South Warner Wilderness, California. Results of this study indicate that little promise for the occurrence of mineral resources exists within the area. Small veins of optical quality calcite occur on the east side of the area but, are not considered a resource.

  9. South American sedimentary basins

    SciTech Connect

    Urien, C.M.

    1984-04-01

    More than 64 sedimentary basins have been identified on the South American continent. According to their regional structural character and tectonic setting, they are classified in 4 super groups. About 20 interior or intracratonic basins occur on South American cratons (Guayanas, Brazilian, and Patagonian). In most cases, their sedimentary fill is Paleozoic or early Mesozoic. Rift or transverse grabens resulting from incipient sea floor spreading extend towards the continental margin. Seventeen basins are located along the Atlantic stable margin, and consist primarily of half grabens with downfaulted seaward blocks. These rifts (or pull-apart basins) were separated as results of the migration of the African and American continental blocks. Therefore the sedimentation is chiefly Cretaceous and Tertiary. On the western edge of South American cratons, almost 20 basins of downwarped blocks extend from Orinoco down to the Malvinas plateau in a relatively uninterrupted chain of retroarc basins, bordered by the Andean orogen. They lie on a flexured Precambrian and Paleozoic basement, and are highly deformed in the west (Subandean belt) due to the action of compressional forces caused by the tectonic influence of the Mesozoic Andean batholith. Westward, the Pacific margin is bordered by 27 foreland and forearc basins, which alternate from north to south on an unstable or quasistable margin, fringed by a trench and slope complex where the ocean crust is subducted beneath the continental plate.

  10. South Georgia Autograph Parties.

    ERIC Educational Resources Information Center

    Womack, Geneva H.

    1978-01-01

    The manager of the South Georgia College Bookstore describes several autograph parties used as a sales promotion technique. The planning process, including initial contacts with the guest authors, are discussed, and the schedules and events of the authors' visits are reviewed. (JMD)

  11. Neptune's 'Hot' South Pole

    NASA Technical Reports Server (NTRS)

    2007-01-01

    These thermal images show a 'hot' south pole on the planet Neptune. These warmer temperatures provide an avenue for methane to escape out of the deep atmosphere.

    The images were obtained with the Very Large Telescope in Chile, using an imager/spectrometer for mid-infrared wavelengths on Sept. 1 and 2, 2006. The telescope is operated by the European Organization for Astronomical Research in the Southern Hemisphere (known as ESO).

    Scientists say Neptune's south pole is 'hotter' than anywhere else on the planet by about 10 degrees Celsius (50 degrees Fahrenheit). The average temperature on Neptune is about minus 200 degrees Celsius (minus 392 degrees Fahrenheit).

    The upper left image samples temperatures near the top of Neptune's troposphere (near 100 millibar pressure, which is one-tenth the Earth atmospheric pressure at sea level). The hottest temperatures are indicated at the lower part of the image, at Neptune's south pole (see the graphic at the upper right). The lower two images, taken 6.3 hours apart, sample temperatures at higher altitudes in Neptune's stratosphere. They do show generally warmer temperatures near, but not at, the south pole. They also show a distinct warm area which can be seen in the lower left image and rotated completely around the back of the planet and returned to the earth-facing hemisphere in the lower right image.

  12. South Platte Data Browser

    EPA Science Inventory

    The common goal among the developers of the South Platte River Basin Data Browser is to improve decision-making relative to environmental management through the development of applied research. The focus of the research has been to design an integrated system of landscape metri...

  13. Trends Abroad: South Africa

    ERIC Educational Resources Information Center

    Varley, Douglas H.

    1970-01-01

    In South Africa today there is a complex structure of laws and regulations which impose a variety of restrictions on individual liberties including the freedom to publish and read literary material. The successive steps by which this state of affairs has been reached are briefly described. (NH)

  14. South Carolina and SREB

    ERIC Educational Resources Information Center

    Southern Regional Education Board (SREB), 2009

    2009-01-01

    The Southern Regional Education Board (SREB) is a nonprofit organization that works collaboratively with South Carolina and 15 other member states to improve education at every level--from pre-K to postdoctoral study--through many effective programs and initiatives. SREB's "Challenge to Lead" Goals for Education, which call for the…

  15. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California-2010

    USGS Publications Warehouse

    Dyke, Jessica; Parcheso, Francis; Thompson, Janet K.; Cain, Daniel J.; Luoma, Samuel N.; Hornberger, Michelle I.

    2011-01-01

    Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 37-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the M. petalum community shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable (2010), with almost all animals initiating reproduction in the fall and spawning the following spring of most years. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that indicates a more stable community that is subjected to fewer stressors. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals; both species had short-lived rebounds in abundance in 2008, 2009, and 2010. Heteromastus filiformis (a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the

  16. Country Energy Profile, South Africa

    SciTech Connect

    1995-08-01

    This country energy profile provides energy and economic information about South Africa. Areas covered include: Economics, demographics, and environment; Energy situation; Energy structure; Energy investment opportunities; Department of Energy (DOE) programs in South Africa; and a listing of International aid to South Africa.

  17. Geography: The South Australian Experience

    ERIC Educational Resources Information Center

    McInerney, Malcolm; Shepherd, Rita

    2006-01-01

    Geography as a discipline has a long and healthy history in South Australia. Due to the passion of individual educators and the activities of the Geography Teachers Association of South Australia (GTASA) since its foundation in 1936, South Australia has experienced ongoing curriculum development and indeed innovation in the geographical studies in…

  18. Emergency nursing in South Africa.

    PubMed

    Brysiewicz, Petra; Bruce, Judy

    2008-04-01

    The role of the emergency nurse in South Africa is a challenging one due to a variety of reasons. This article describes the healthcare system of South Africa with particular attention to the emergency medical system as well as the reason why most emergency clients present to the emergency departments. The actual experience of working as an emergency nurse in South Africa is highlighted.

  19. Characterizing and Cataloguing Star-Forming Galaxies in Preparation for the LADUMA Survey

    NASA Astrophysics Data System (ADS)

    Perez, Manuel Joe; Baker, Andrew J.; Wu, John F.

    2017-01-01

    This poster presents the results of an effort to process, characterize, and catalog the optical spectra of ~ 1,500 star-forming galaxies, located in the Extended Chandra Deep Field South (ECDFS), which will be used in stacking experiments by the Looking At the Distant Universe with the MeerKAT Array (LADUMA) deep HI survey. The LADUMA HI data will be used to study the evolution of the Tully-Fisher relation, cosmic neutral gas density, and other intrinsic properties of galaxies as a function of redshift. The stacking component of this research will rely on large catalogs of star-forming galaxies in the ECDFS, categorized according to star-formation rate (SFR), metallicity, stellar color excess, and redshift. We used optical spectra obtained with the Anglo-Australian Telescope, for which we have developed an automated pipeline to calculate extinction-corrected line fluxes, SFRs, and various metallicity diagnostics. The pipeline ultimately provides a visualization of the objects and their intrinsic properties as related to redshift for future analysis by the LADUMA team. This work has been supported by NSF grant PHY-1560077.

  20. DUST-CORRECTED COLORS REVEAL BIMODALITY IN THE HOST-GALAXY COLORS OF ACTIVE GALACTIC NUCLEI AT z {approx} 1

    SciTech Connect

    Cardamone, Carolin N.; Megan Urry, C.; Brammer, Gabriel; Schawinski, Kevin; Treister, Ezequiel; Gawiser, Eric

    2010-09-20

    Using new, highly accurate photometric redshifts from the MUSYC medium-band survey in the Extended Chandra Deep Field-South (ECDF-S), we fit synthetic stellar population models to compare active galactic nucleus (AGN) host galaxies to inactive galaxies at 0.8 {<=} z {<=} 1.2. We find that AGN host galaxies are predominantly massive galaxies on the red sequence and in the green valley of the color-mass diagram. Because both passive and dusty galaxies can appear red in optical colors, we use rest-frame near-infrared colors to separate passively evolving stellar populations from galaxies that are reddened by dust. As with the overall galaxy population, {approx}25% of the 'red' AGN host galaxies and {approx}75% of the 'green' AGN host galaxies have colors consistent with young stellar populations reddened by dust. The dust-corrected rest-frame optical colors are the blue colors of star-forming galaxies, which imply that these AGN hosts are not passively aging to the red sequence. At z {approx} 1, AGN activity is roughly evenly split between two modes of black hole growth: the first in passively evolving host galaxies, which may be heating up the galaxy's gas and preventing future episodes of star formation, and the second in dust-reddened young galaxies, which may be ionizing the galaxy's interstellar medium and shutting down star formation.

  1. Anaglyph, South America

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This anaglyph (stereoscopic view) of South America was generated with data from the Shuttle Radar Topography Mission (SRTM). It is best viewed at or near full resolution with anaglyph glasses. For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south but variable east-west), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the South American continent is readily apparent.

    Topographic relief in South America is dominated by the Andes Mountains, which extend all along the Pacific Coast. These mountains are created primarily by the convergence of the Nazca and South American tectonic plates. The Nazca Plate, which underlies the eastern Pacific Ocean, slides under western South America resulting in crustal thickening, uplift, and volcanism. Another zone of plate convergence occurs along the northwestern coast of South America where the Caribbean Plate also slides under the South American Plate and forms the northeastern extension of the Andes Mountains.

    East of the Andes, much of northern South America drains into the Amazon River, the world's largest river in terms of both watershed area and flow volume. Topographic relief is very low in much of the Amazon Basin but SRTM data provide an excellent detailed look at the basin's three-dimensional drainage pattern, including the geologic structural trough (syncline) that hosts the eastern river channel.

    North of the Amazon, the Guiana Highlands commonly stand in sharp contrast to the surrounding lowlands, indeed hosting the world's tallest waterfall, Angel Falls (979 meters or 3212 feet). Folded and fractured bedrock structures are distinctive in the topographic pattern.

    South of the Amazon, the Brazilian

  2. South Oregon Coast Reinforcement.

    SciTech Connect

    United States. Bonneville Power Administration.

    1998-05-01

    The Bonneville Power Administration is proposing to build a transmission line to reinforce electrical service to the southern coast of Oregon. This FYI outlines the proposal, tells how one can learn more, and how one can share ideas and opinions. The project will reinforce Oregon`s south coast area and provide the necessary transmission for Nucor Corporation to build a new steel mill in the Coos Bay/North Bend area. The proposed plant, which would use mostly recycled scrap metal, would produce rolled steel products. The plant would require a large amount of electrical power to run the furnace used in its steel-making process. In addition to the potential steel mill, electrical loads in the south Oregon coast area are expected to continue to grow.

  3. South Polar Layers

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-516, 17 October 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, stair-stepped layers in the south polar region of Mars. These layers have been considered, for the past three decades, to consist of a mixture of dust and ice. The Mars Polar Lander (MPL) mission was designed to test this hypothesis. However, sadly, MPL was lost during descent in December 1999. This exposure of south polar layered material is located near 86.3oS, 187.7oW. The image covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the upper left.

  4. South Atlantic interbasin exchange

    NASA Technical Reports Server (NTRS)

    Rintoul, Stephen Rich

    1991-01-01

    The exchange of mass and heat between the South Atlantic and the neighboring ocean basins was estimated using hydrographic data and inverse methods, in order to gain information on the links between the deep-water formation processes occurring within the Atlantic and the global thermohaline circulation. Results demonstrate that the global thermohaline cell associated with the formation and export of North Atlantic deep water (NADW) is closed primarily by a 'cold water path' in which deep water leaving the Atlantic ultimately returns as intermediate water entering the basin through Drake Passage. This conclusion conflicts with the suggestion by Gordon (1986) that the global thermohaline circulation associated with the formation of NADW is closed primarily by a 'warm water path', in which the export of NADW is compensated by an inflow of warm Indian Ocean thermocline water south of Africa.

  5. Summer South Polar Cap

    NASA Technical Reports Server (NTRS)

    2004-01-01

    13 April 2004 The martian south polar residual ice cap is composed mainly of frozen carbon dioxide. Each summer, a little bit of this carbon dioxide sublimes away. Pits grow larger, and mesas get smaller, as this process continues from year to year. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of a small portion of the south polar cap as it appeared in mid-summer in January 2004. The dark areas may be places where the frozen carbon dioxide contains impurities, such as dust, or places where sublimation of ice has roughened the surface so that it appears darker because of small shadows cast by irregularities in the roughened surface. The image is located near 86.9oS, 7.6oW. The image covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

  6. Terrorism in South Africa.

    PubMed

    MacFarlane, Campbell

    2003-01-01

    The Republic of South Africa lies at the southern tip of the African continent. The population encompasses a variety of races, ethnic groups, religions, and cultural identities. The country has had a turbulent history from early tribal conflicts, colonialisation, the apartheid period, and post-apartheid readjustment. Modern terrorism developed mainly during the apartheid period, both by activities of the state and by the liberation movements that continued to the time of the first democratic elections in 1994, which saw South Africa evolve into a fully representative democratic state with equal rights for all. Since 1994, terrorist acts have been criminal-based, evolving in the Cape Town area to political acts, largely laid at the feet of a predominantly Muslim organisation, People against Gangsterism and Drugs, a vigilant organisation allegedly infiltrated by Muslim fundamentalists. Along with this, has been terrorist activities, mainly bombings by disaffected members of white, right-wing groups. In the apartheid era, a Draconian series of laws was enacted to suppress liberation activities. After 1994, most of these were repealed and new legislation was enacted, particularly after the events of 11 September 2001; this legislation allows the government to act against terrorism within the constraints of a democratic system. Disaster management in South Africa has been largely local authority-based, with input from provincial authorities and Civil Defence. After 1994, attempts were made to improve this situation, and national direction was provided. After 11 September 2001, activity was increased and the Disaster Management Act 2002 was brought into effect. This standardized disaster management system at national, provincial, and local levels, also facilites risk assessment and limitation as well as disaster mitigation. The potential still exists for terrorism, mainly from right-wing and Muslim fundamentalist groups, but the new legislation should stimulate disaster

  7. AIDS in South Africa.

    PubMed

    Ijsselmuiden, C; Evian, C; Matjilla, J; Steinberg, M; Schneider, H

    1993-01-01

    The National AIDS Convention in South Africa (NACOSA) in October 1992 was the first real attempt to address HIV/AIDS. In Soweto, government, the African National Congress, nongovernmental organizations, and organized industry and labor representatives worked for 2 days to develop a national plan of action, but it did not result in a united effort to fight AIDS. The highest HIV infection rates in South Africa are among the KwaZulu in Natal, yet the Inkatha Freedom Party did not attend NACOSA. This episode exemplifies the key obstacles for South Africa to prevent and control AIDS. Inequality of access to health care may explain why health workers did not diagnose the first AIDS case in blacks until 1985. Migrant labor, Bantu education, and uprooted communities affect the epidemiology of HIV infection. Further, political and social polarization between blacks and whites contributes to a mindset that AIDS is limited to the other race which only diminishes the personal and collective sense of susceptibility and the volition and aptitude to act. The Department of National Health and Population Development's voluntary register of anonymously reported cases of AIDS specifies 1517 cumulative AIDS cases (October 1992), but this number is low. Seroprevalence studies show between 400,000-450,000 HIV positive cases. Public hospitals cannot give AIDS patients AZT and DDI. Few communities provided community-based care. Not all hospitals honor confidentiality and patients' need for autonomy. Even though HIV testing is not mandatory, it is required sometimes, e.g., HIV testing of immigrants. AIDS Training, Information and Counselling Centers are in urban areas, but not in poor areas where the need is most acute. The government just recently developed in AIDS education package for schools, but too many people consider it improper, so it is not being used. The poor quality education provided blacks would make it useless anyhow. Lifting of the academic boycott will allow South African

  8. Profile of South Africa

    SciTech Connect

    Fox, G.J.; Tonneson, L.C.

    1996-08-01

    A broad overview of the Republic of South Africa`s nuclear energy program is presented. Economic aspects are the main focus of the article, and numerical data is provided for electricity generation and use and uranium production. The role of the molecular laser isotope process for enrichment is discussed. The research reactor program, waste disposal and decommissioning, mining history, uranium production, and nonproliferation policy are other highlighted topics.

  9. South Dakota geothermal handbook

    SciTech Connect

    Not Available

    1980-06-01

    The sources of geothermal fluids in South Dakota are described and some of the problems that exist in utilization and materials selection are described. Methods of heat extraction and the environmental concerns that accompany geothermal fluid development are briefly described. Governmental rules, regulations and legislation are explained. The time and steps necessary to bring about the development of the geothermal resource are explained in detail. Some of the federal incentives that encourage the use of geothermal energy are summarized. (MHR)

  10. Terrorism in South Asia

    DTIC Science & Technology

    2004-08-09

    and their supporters in South Asia is identified as a threat to both regional stability and to the attainment of central U.S. policy goals. Al Qaeda...forces that fled from Afghanistan with their Taliban supporters remain active on Pakistani territory, and Al Qaeda is believed to have links with...portion of Pakistan’s ethnic Pashtun population is reported to sympathize with the Taliban and even Al Qaeda. The United States maintains close

  11. Significant gas field fans out in S. Louisiana

    SciTech Connect

    Not Available

    1991-02-18

    This paper reports on the completion of producing wells in Chalkley Oligocene Miogypsinoides gas/condensate field of Cameron Parish, La. The field appears to be one of the largest gas discoveries in South Louisiana in several years.

  12. Marketing of irradiated commodities in South Africa

    NASA Astrophysics Data System (ADS)

    Du Plessis, TA; Stevens, RCB

    Although the industrial exploitation of radiation processing in the medical and allied fields has been successfully marketed and applied for the past two decades in South Africa, the introduction of food radurisation on an industrial level adds a completely new dimension to the marketing of this processing technique. Extensive research into the use of radiation for the treatment of various foodstuffs has been carried out by the Nuclear Development Corporation of South Africa for more than a decade, resulting in South Africa being one of the first countries where a commercial irradiator dedicated to this branch of radiation processing, was established. The marketing of this process is especially difficult due to the emotive aspects associated with radiation and man's sensitive reaction to anything pertaining to his food. This situation was made even more difficult by the general public's apprehension towards nuclear activities throughout the world. In an attempt to transform the unfavourable public image associated with this process, an important first step was to form a National Steering Committee for the Marketing of Radurised Food, the members of which were drawn from various agricultural controlling bodies, the Department of Health, and other controlling bodies held in high esteem by the public, such as the Consumer Council and representatives from commerce and industry. This approach proved to be very successful and greatly assisted in creating a climate whereby the public in South Africa today generally has a favourable attitude towards the radurisation of foodstuffs. The development of this marketing strategy for food radurisation in South Africa is discussed in detail.

  13. The 10 Meter South Pole Telescope

    NASA Astrophysics Data System (ADS)

    Carlstrom, J. E.; Ade, P. A. R.; Aird, K. A.; Benson, B. A.; Bleem, L. E.; Busetti, S.; Chang, C. L.; Chauvin, E.; Cho, H.-M.; Crawford, T. M.; Crites, A. T.; Dobbs, M. A.; Halverson, N. W.; Heimsath, S.; Holzapfel, W. L.; Hrubes, J. D.; Joy, M.; Keisler, R.; Lanting, T. M.; Lee, A. T.; Leitch, E. M.; Leong, J.; Lu, W.; Lueker, M.; Luong-Van, D.; McMahon, J. J.; Mehl, J.; Meyer, S. S.; Mohr, J. J.; Montroy, T. E.; Padin, S.; Plagge, T.; Pryke, C.; Ruhl, J. E.; Schaffer, K. K.; Schwan, D.; Shirokoff, E.; Spieler, H. G.; Staniszewski, Z.; Stark, A. A.; Tucker, C.; Vanderlinde, K.; Vieira, J. D.; Williamson, R.

    2011-05-01

    The South Pole Telescope (SPT) is a 10 m diameter, wide-field, offset Gregorian telescope with a 966 pixel, multicolor, millimeter-wave, bolometer camera. It is located at the Amundsen-Scott South Pole station in Antarctica. The design of the SPT emphasizes careful control of spillover and scattering, to minimize noise and false signals due to ground pickup. The key initial project is a large-area survey at wavelengths of 3, 2, and 1.3 mm, to detect clusters of galaxies via the Sunyaev-Zel’dovich effect and to measure the small-scale angular power spectrum of the cosmic microwave background (CMB). The data will be used to characterize the primordial matter power spectrum and to place constraints on the equation of state of dark energy. A second-generation camera will measure the polarization of the CMB, potentially leading to constraints on the neutrino mass and the energy scale of inflation.

  14. Gravity and geoid model for South America

    NASA Astrophysics Data System (ADS)

    Blitzkow, Denizar; Oliveira Cancoro de Matos, Ana Cristina; do Nascimento Guimarães, Gabriel; Pacino, María Cristina; Andrés Lauría, Eduardo; Nunes, Marcelo; Castro Junior, Carlos Alberto Correia e.; Flores, Fredy; Orihuela Guevara, Nuris; Alvarez, Ruber; Napoleon Hernandez, José

    2016-04-01

    In the last 20 years, South America Gravity Studies (SAGS) project has undertaken an ongoing effort in establishing the fundamental gravity network (FGN); terrestrial, river and airborne relative gravity densifications; absolute gravity surveys and geoid (quasi-geoid) model computation for South America. The old FGN is being replaced progressively by new absolute measurements in different countries. In recent years, Argentina, Bolivia, Brazil, Ecuador, Paraguay and Venezuela organizations participated with relative gravity surveys. Taking advantage of the large amount of data available, GEOID2015 model was developed for 15°N and 57°S latitude and 30 ° W and 95°W longitude based on EIGEN-6C4 until degree and order 200 as a reference field. The ocean area was completed with mean free air gravity anomalies derived from DTU10 model. The short wavelength component was estimated using FFT. The global gravity field models EIGEN-6C4, DIR_R5 were used for comparison with the new model. The new geoid model has been evaluated against 1,319 GPS/BM, in which 592 are located in Brazil and the reminder in other countries. The preliminary RMS difference between GPS/BM and GEOID2015 throughout South America and in Brazil is 46 cm and 17 cm, respectively. New activities are carrying out with the support of the IGC (Geographic and Cartographic Institute) under the coordination of EPUSP/LTG and CENEGEO (Centro de Estudos de Geodesia). The new project aims to establish new gravity points with the A-10 absolute gravimeter in South America. Recent such surveys occurred in São Paulo state, Argentina and Venezuela.

  15. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2014

    USGS Publications Warehouse

    Cain, Daniel J.; Thompson, Janet K.; Crauder, Jeff; Parcheso, Francis; Stewart, Robin; Kleckner, Amy E.; Dyke, Jessica; Hornberger, Michelle I.; Luoma, Samuel N.

    2015-01-01

    Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 40-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of M. petalum shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable (2014), with almost all animals initiating reproduction in the fall and spawning the following spring. The entire infaunal community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that indicates a more stable community that is subjected to fewer stressors. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals; both species had short-lived rebounds in abundance in 2008, 2009, and 2010. Heteromastus filiformis (a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying its eggs on or in the sediment) showed a concurrent increase in dominance and, in the last several years before 2008, showed a stable population. H. filiformis abundance increased slightly in 2011–2012 and returned to pre-2011 numbers in 2014. An unidentified disturbance occurred on the mudflat in early 2008 that resulted in the loss of the benthic animals, except for deep-dwelling animals like Macoma petalum. However, within two months of this event animals returned to the mudflat. The resilience of the community suggested that the disturbance was not due to a persistent toxin or to anoxia. The reproductive mode of most species present in 2014 is

  16. The Cretaceous opening of the South Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Granot, Roi; Dyment, Jérôme

    2015-03-01

    The separation of South America from Africa during the Cretaceous is poorly understood due to the long period of stable polarity of the geomagnetic field, the Cretaceous Normal Superchron (CNS, lasted between ∼121 and 83.6 Myr ago). We present a new identification of magnetic anomalies located within the southern South Atlantic magnetic quiet zones that have arisen due to past variations in the strength of the dipolar geomagnetic field. Using these anomalies, together with fracture zone locations, we calculate the first set of magnetic anomalies-based finite rotation parameters for South America and Africa during that period. The kinematic solutions are generally consistent with fracture zone traces and magnetic anomalies outside the area used to construct them. The rotations indicate that seafloor spreading rates increased steadily throughout most of the Cretaceous and decreased sharply at around 80 Myr ago. A change in plate motion took place in the middle of the superchron, roughly 100 Myr ago, around the time of the final breakup (i.e., separation of continental-oceanic boundary in the Equatorial Atlantic). Prominent misfit between the calculated synthetic flowlines (older than Anomaly Q1) and the fracture zones straddling the African Plate in the central South Atlantic could only be explained by a combination of seafloor asymmetry and internal dextral motion (<100 km) within South America, west of the Rio Grande fracture zone. This process has lasted until ∼92 Myr ago after which both Africa and South America (south of the equator) behaved rigidly. The clearing of the continental-oceanic boundaries within the Equatorial Atlantic Gateway was probably completed by ∼95 Myr ago. The clearing was followed by a progressive widening and deepening of the passageway, leading to the emergence of north-south flow of intermediate and deep-water which might have triggered the global cooling of bottom water and the end for the Cretaceous greenhouse period.

  17. The South Pacific superswell

    NASA Astrophysics Data System (ADS)

    McNutt, Marcia K.; Fischer, Karen M.

    Seafloor depths in a broad area of French Polynesia are 250 to 750 m shallower than lithosphere of the same age in the North Pacific and the North Atlantic. The area of shallow seafloor also correlates with a region of high density of volcanoes, low seismic velocity in the upper mantle, and a reduction in the thickness of the elastic plate supporting the volcanoes. The Marquesas fracture zone marks an abrupt transition between normal lithosphere to the north which follows the thermal subsidence curve for a 125-km-thick plate and shallow lithosphere to the south which behaves as though it is only 75-km thick. This age dependence in the French Polynesian depth anomalies, the low elastic plate thickness, and the change in depth at the Marquesas fracture zone, a lithospheric discontinuity, require elevated temperatures in the lithosphere. The pattern and amplitude of the depth anomaly is not consistent with the notion that it results from lithospheric thinning beneath a number of overlapping hot spot swells. Rather, we propose that hot spot traces cluster in this region because the lithosphere is already thinner and more vulnerable to magma penetration. The reduction in the thickness of the thermal plate is presumably due to enhanced small-scale convection resulting from the thermal and/or chemical effect of a broad mantle up welling beneath the South Pacific as imaged by seismic tomography. The morphologic and petrologic characteristics of this superswell resemble those that existed in the mid-Cretaceous over H. W. Menard's Darwin Rise, a region of the Pacific which includes the Mid-Pacific Mountains, the Marshall Islands, Magellan Seamounts, and Wake Guyots. We propose that the South Pacific superswell is the modern-day equivalent of the Darwin Rise, and that it may be merely an extreme example of global variability in lithospheric thermal structure as a function of temperature, chemistry, and/or state-of-stress in the upper mantle.

  18. Lightning medicine in South Africa.

    PubMed

    Blumenthal, Ryan; Trengrove, Estelle; Jandrell, Ian R; Saayman, Gert

    2012-06-06

    South Africa has a rich history of lightning research; however, research on the clinical and pathological effects and features of lightning-related injury (keraunomedicine or lightning medicine) remains neglected locally. By providing an overview of keraunomedicine and focussing on South African perspectives, we hope to raise awareness and propose that a concerted and co-ordinated attempt be made to report and collate data regarding lightning strike victims in South Africa.

  19. South Polar Scene

    NASA Technical Reports Server (NTRS)

    2006-01-01

    19 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer scene in the south polar region of the red planet. The light-toned surface is covered with seasonal frost that, later in the season, would have sublimed away.

    Location near: 86.8oS, 322.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  20. South Polar Polygons

    NASA Technical Reports Server (NTRS)

    2005-01-01

    4 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polgyon-cracked surface, into which deep, somewhat kidney-bean-shaped pits have formed. These are landscapes of the martian south polar residual cap. This view was captured during May 2005.

    Location near: 86.9oS, 5.1oW Image width: 1.5 km (0.9 mi) Illumination from: upper left Season Southern Spring

  1. South Polar Scene

    NASA Technical Reports Server (NTRS)

    2004-01-01

    5 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of the south polar residual cap. Sunlight illuminates this scene from the upper left, thus the somewhat kidney bean-shaped features are pits, not mounds. These pits and their neighboring polygonal cracks are formed in a material composed mostly of carbon dioxide ice. The image is located near 87.0oS, 5.7oW, and covers an area 3 km (1.9 mi) wide.

  2. Home Reef, South Pacific

    NASA Technical Reports Server (NTRS)

    2006-01-01

    In the South Pacific, south of Late Island along the Tofua volcanic arc in Tonga, a new volcanic island Home Reef is being re-born. The island is thought to have emerged after a volcanic eruption in mid-August that has also spewed large amounts of floating pumice into Tongan waters and sweeping across to Fiji about 350 km (220 miles) to the west of where the new island has formed. In 2004 a similar eruption created an ephemeral island about 0.5 by 1.5 km (0.3 by 0.9 miles) in size; it was no longer visible in an ASTER image acquired November 2005. This simulated natural color image shows the vegetation-covered stratovolcanic island of Late in the upper right. Home Reef is found in the lower left. The two bluish plumes are hot seawater that is laden with volcanic ash and chemicals; the larger one can be traced for more than 14 km (8.4 miles) to the east. The image was acquired October 10, 2006 and covers an area of 24.3 by 30.2 km. It is located at 18.9 degrees South latitude, 174.7 degrees west longitude.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation

  3. South Polar Erosion

    NASA Technical Reports Server (NTRS)

    2004-01-01

    24 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of erosion acting upon a layer of material in the south polar region of Mars. The elliptical pit in the lower left corner of the image was once buried beneath this eroding layer, as well. The processes that eroded the material, and the composition of the material, are unknown. The image is located near 80.7oS, 300.9oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates this scene from the top.

  4. South Polar Depression

    NASA Technical Reports Server (NTRS)

    2005-01-01

    14 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a circular depression and a suite of eroding mesas of carbon dioxide. These features occur in the south polar residual cap of Mars. The eroding carbon dioxide creates landforms reminiscent of 'Swiss cheese.' The circular feature might indicate the location of a filled, buried impact crater.

    Location near: 86.8oS, 111.0oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  5. South Asia: Danger Ahead?

    DTIC Science & Technology

    2011-01-01

    2011 4 . TITLE AND SUBTITLE South Asia: Danger Ahead? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...its opponent and preclude a devastating retaliatory response. 4 Fundamen­ tally, both countries are restricted to use their nuclear forces to threaten...threaten India’s hold in the Kashmir Valley; to control a part of the Himalayan Range to facili­ tate insurgent movement into the Kashmir Valley and the

  6. The Emergence of Research in the South African Academic Development Movement

    ERIC Educational Resources Information Center

    Boughey, Chrissie; Niven, Penny

    2012-01-01

    This paper uses an analytical framework developed from the work of philosopher Roy Bhaskar and sociologist Margaret Archer to explore the emergence of a body of research on teaching and learning in South African higher education. This research, generated in a field known as "Academic Development" in South Africa and as "Educational…

  7. Grass hosts of cereal aphids (Hemiptera: Aphididae) between wheat-cropping cycles in South Dakota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several grasses may serve as alternative hosts for cereal aphids during the interim between small-grain crops in South Dakota, but field studies to determine which grasses are important have not been undertaken. We sampled annual and perennial grasses for cereal aphids in 18 counties in South Dakot...

  8. Short Course in South Asian Literature and Culture. Fulbright-Hays Summer Seminar Abroad 1994 (India).

    ERIC Educational Resources Information Center

    Shlensky, Jane

    This syllabus describes a college course developed to address South Asian literature and culture with a focus on India. Suggestions for student readings and discussion, oral communication, listening, writing, and field trips are included. The empires of South Asia, its religions, social stratification, parallels of history and religion with the…

  9. History, Current Status, and Future Prospects of Counseling in South Korea

    ERIC Educational Resources Information Center

    Lee, Sang Min; Suh, Suhyun; Yang, Eunjoo; Jang, Yoo Jin

    2012-01-01

    Although the counseling profession was introduced to South Korea in the 1950s by American delegates of education, counseling has been only lately recognized as a specialized field that requires distinctive knowledge and skills. In this article, the authors describe the history and the current status of counseling in South Korea and then discuss…

  10. Educational Administration as National Capacity Building: Towards South Korea Becoming a Creative Learning State

    ERIC Educational Resources Information Center

    Macpherson, Reynold; Sun Hyung, Park

    2015-01-01

    This philosophy paper proposes that a primary purpose of Educational Administration, as a field of study, research and practice in South Korea, becomes national capacity building. It does this by evaluating the current scope of Educational Administration against the need for a new national education policy to help South Korea make the transition…

  11. Career Counselling in the 21st Century: South African Institutions of Higher Education at the Crossroads

    ERIC Educational Resources Information Center

    Maree, J. G.

    2009-01-01

    The current state of career counselling in South African institutions of higher education in the 21st century is explored in this article in an attempt to locate current work in the field of career counselling in South Africa in the light of global trends (academic and economic) and in terms of local history and current economic climate. The…

  12. 11. BUILDING 522, INTERIOR, SOUTH MEZZANINE, FROM SOUTH WALL APPROXIMATELY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. BUILDING 522, INTERIOR, SOUTH MEZZANINE, FROM SOUTH WALL APPROXIMATELY ONE-THIRD OF DISTANCE WEST FROM EAST END, LOOKING EAST-NORTHEAST. - Oakland Naval Supply Center, Aeronautical Materials Storehouses, Between E & G Streets, between Fourth & Sixth Streets, Oakland, Alameda County, CA

  13. 5. View of south tower, facing northnortheast from south bank ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. View of south tower, facing north-northeast from south bank of the Columbia River. Center tower and north tower in background, lower right. - Pasco-Kennewick Transmission Line, Columbia River Crossing Towers, Columbia Drive & Gum Street, Kennewick, Benton County, WA

  14. 149. INTERIOR, EIGHTH FLOOR, SOUTH PENTHOUSE, FORMERLY EMPLOYEES' LOUNGE, SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    149. INTERIOR, EIGHTH FLOOR, SOUTH PENTHOUSE, FORMERLY EMPLOYEES' LOUNGE, SOUTH ANNEX, DETAIL OF BRONZE WALL LIGHTING FIXTURE (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  15. JPRS Report, Near East & South Asia

    DTIC Science & Technology

    2007-11-02

    Textile Trade Predicted To Peak [GULF NEWS 19 Nov] 66 Study Provides Work Force Statistics [AL-KHALU 9 Nov] 67 SOUTH ASIA AFGHANISTAN Fall in...year. "In the data-bank," said al-Khalil, "we will be going into other fields of study to find out what are the problems and potential dangers...a statistical study released by the Arab League today. The study reached the conclusion by comparing the Arab world with the advanced nations in

  16. The South Pole and the Ross Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image shows a rare clear view of the South Pole (lower right) and the Ross Sea, Antarctica. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) acquired the scene on December 26, 2001. The geographic South Pole is located in the center of Antarctica, at an altitude of 2,900 meters (9,300 feet). It rests on a continent-wide ice sheet that is 2,870 m thick, with the underlying bedrock only 30 m (98 feet) above sea level. The ice underlying the South Pole is as much as 140,000 years old, and is currently accumulating at about 82 cm (32 inches) per year. Roughly 2,500 km (1,550 miles) away is the green water of the Ross Sea, which indicates the presence of large numbers of phytoplankton. This is a highly productive part of the world's oceans. Also note the ice gathered around McMurdo Sound, seen toward the lefthand shoreline of the Ross Sea, at the edge of the Ross Ice Shelf. According to National Science Foundation researchers, this ice is making it difficult for penguins to reach their food supply. Separating the continental Antarctic ice sheet from the Ross Sea are the Queen Maud Mountains and the Ross Ice Shelf. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  17. The Gattini South Pole UV experiment

    NASA Astrophysics Data System (ADS)

    Moore, Anna M.; Ahmed, Sara; Ashley, Michael C. B.; Croner, Ernest; Delacroix, Alex; Ebihara, Yusuke; Fucik, Jason; Martin, D. Christopher; Velur, Viswa; Weatherwax, Allan

    2012-09-01

    The Gattini South Pole UV experiment (Gattini SPUV) was deployed to the South Pole dark sector in February 2010 and has recently completed a highly successful first season of winter time observations. The experiment has, for the first time ever, measured and categorized the optical night sky brightness at the very blue wavelengths. The experiment consists of a remotely operated 6” aperture custom designed telescope. The telescope feeds a blue sensitive imager with 4 degree field of view that contains a bank of 3 filters: SDSS g’, Bessel U and a custom “super U” filter specifically designed to probe the sky emission at wavelengths approaching the atmospheric cut-off. The filters are continually cycled with exposure times ranging from 30 to 300 seconds throughout the winter period. The telescope, in addition, feeds a 2 degree long slit VPH grating spectrograph with R~1000. The bandwidth is 350-450nm. The spectra are recorded simultaneously with the imager exposures. The experiment is designed for low temperature Antarctic operation and resides on the roof of the MAPO building in the South Pole Antarctic sector. The primary science goals are to categorize the Antarctic winter-time sky background at the very bluest of wavelengths as a pathfinder for the Antarctic Cosmic Web Imager. We present a technical overview of the experiment and results from the first winter season.

  18. South Perimeter Road, view to the east. One and twocar ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South Perimeter Road, view to the east. One- and two-car garages are visible at left; a row of citrus trees separate the road from a ball field at right; and a weather station is in the right foreground - Wellton-Mohawk Irrigation System, Building No. 1 (House), 30601 Wellton-Mohawk Drive, Wellton, Yuma County, AZ

  19. Soil-moisture ground truth, Hand County, South Dakota

    NASA Technical Reports Server (NTRS)

    Jones, E. B.

    1976-01-01

    Soil types were determined from the Soil Survey of Hand County, South Dakota. The soil types encountered on the soil moisture lines are summarized. The actual soil moisture data are presented. The data have been divided by range, township and section. The soil moisture data obtained in fields of winter wheat and spring wheat are briefly summarized.

  20. Clifford Malcolm: Glimpses of His South African Legacy of Hope

    ERIC Educational Resources Information Center

    Govender, Nadaraj; Ramsuran, Anitha; Dhunpath, Rubby

    2008-01-01

    This article reviews the contributions of Cliff Malcolm while in South Africa during the period 1997-2005. It focuses on his contribution to the fields of science education, teacher education, learner-centered education, transformational outcomes-based education and HIV/AIDS education. In this paper we provide snapshots of his work as an academic,…

  1. Towards CONFINTEA VI: Lifelong Learning Advocacy in South Eastern Europe

    ERIC Educational Resources Information Center

    Dimitrova, Anelia

    2007-01-01

    Adult learning is a field that has so far been neglected in education and training reforms in South Eastern European countries and territories but which is beginning to emerge as an important policy area. Further efforts are needed to foster national policy debate about the importance of lifelong learning (and adult education as a vital component…

  2. Doing Justice to Social Justice in South African Higher Education

    ERIC Educational Resources Information Center

    Tjabane, Masebala; Pillay, Venitha

    2011-01-01

    This paper attempts to develop a conceptualisation of social justice in higher education based on a close reading of the current literature in the field. An important assumption we make is that higher education is a valuable mechanism for social justice. We set the literature against policy documents that detail South African aspirations with…

  3. College Women and the Job Market in the South, 1980.

    ERIC Educational Resources Information Center

    Galambos, Eva C.

    To provide women of the region and their counselors with information for assessing choices of college majors and career plans, the Southern Regional Education Board Manpower and Education Project findings on the employment outlook in the South for college graduates in various fields of study were refined to differentiate the total projected supply…

  4. Overview of buildings from southeast corner of parking lot south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Overview of buildings from southeast corner of parking lot south of Building No. 901, looking 294 degrees west-northwest - Presidio of San Francisco, Enlisted Men's Barracks Type, West end of Crissy Field, between Pearce & Maudlin Streets, San Francisco, San Francisco County, CA

  5. SOUTH FLORIDA MERCURY MONITORING AND MODELING PILOT STUDY

    EPA Science Inventory

    In 1995, the South Florida Atmospheric Mercury Monitoring Study was established to investigate several likely sources of Hg, as well as transport and deposition mechanisms. Field operations began on August 10, 1995, and ran continuously through September 6, 1995. Source sampl...

  6. Landscapes of Leadership in South African Schools: Mapping the Changes

    ERIC Educational Resources Information Center

    Christie, Pam

    2010-01-01

    This article argues that the work of school principals in South Africa is shaped by two major sets of constructs or "landscapes": the literature on leadership and management which provides particular constructions of the field and its changes; and the terrain of new policy frameworks adopted after apartheid to transform the education…

  7. South elevation of Superintendent's Quarters, built as a combination staff ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South elevation of Superintendent's Quarters, built as a combination staff living quarters/office and a visitor reception room by the War Department in 1923-24. Note exterior door to Gold Star Mothers' reception room on right. - Flanders Field American Cemetery & Memorial, Superintendent's Quarters, Wortegemseweg 117, Waregem, West Flanders (Belgium)

  8. Fiji in the South Pacific.

    ERIC Educational Resources Information Center

    Scott, Rosalind; Semaan, Leslie

    This text introduces Fiji and other island nations located in the Pacific, the world's largest ocean. Cut off from the world by vast expanses of water, these people developed a unique culture. Contents include: Teacher Overview, Geography of the South Pacific Islands, History of the South Pacific, Fiji, Traditional Village Life, Yaquna Ceremony,…

  9. Guayule rubber for South Africa

    SciTech Connect

    Not Available

    1981-06-17

    It is reported that Agtec together with South Africa's Council for Scientific and Industrial Research, is investigating the possibility of large-scale production of guayule. The rubber-yielding shrub grows in semi-arid climates and may be the source of a $35-million natural rubber industry in South Africa.

  10. School Psychology in South America.

    ERIC Educational Resources Information Center

    Wechsler, Solange; Oakland, Thomas

    The literature discussing professional practices of school psychology in South America is very meager. This study attempted to identify demographic characteristics of school psychologists in four South American countries, their typical responsibilities, significant problems, and threats that jeopardize the delivery of psychological services within…

  11. South Carolina Trade Examinations Handbook.

    ERIC Educational Resources Information Center

    Crook, Shirley J.

    The South Carolina Trade Examinations for Trade and Industrial Education teachers are administered semi-annually by the South Carolina State Department of Education, Office of Vocational Education, Vocational Teacher Education Programs Unit. This handbook is designed to provide prospective trade and industrial education teachers, vocational…

  12. Assessing wind erosion in South Tunisia

    NASA Astrophysics Data System (ADS)

    Taieb Labiadh, Mohamed; Bouet, Christel; Bergametti, Gilles; Rajot, Jean Louis; Laurent, Benoit; Marticorena, Béatrice

    2013-04-01

    Wind erosion in arid and semi-arid regions of South Tunisia is the main process of land degradation because the precipitations in these areas are low (below 200 mm) and the soils are shallow and sandy, that is to say the easiest to erode [Chepil, 1951]. Even sporadic, precipitations are sufficient to allow vegetation and agriculture (crops and livestock farming) to develop in these regions. In natural conditions, the perennial vegetation cover (even low) protects soils against wind erosion and surface crusting contributes to the stability of the non-vegetated areas by increasing soil cohesion. The use of these natural surfaces for agricultural purposes disturbs this equilibrium and favours wind erosion (i) by lowering/suppressing the vegetal cover, and (ii) by destroying soil crusts, by tillage or by livestock grazing and trampling. In South Tunisia, the use of modern ploughing techniques, replacing the traditional ones, has led to an increase in wind erosion. As an example, the increasing use of the one-way disc plough instead of the traditional tiller plough has had important consequences on the land degradation by modifying soil structure and the characteristics of soil surfaces. The measurements of the wind erosion fluxes acquired by Labiadh et al. [2013] in a field of South Tunisia ploughed using different tillage tools (mouldboard, tillage, disc) exhibited differences in the wind erosion fluxes of about a factor 4 between disc and tiller and of an order of magnitude between disc and mouldboard. There is a lack of quantitative estimates of this phenomenon at the regional scale. The aim of this work is to develop and validate a numerical model that will allow wind erosion quantification in South Tunisia. Once validated, the methodology and the model could be used to quantify wind erosion in other semi-arid cultivated regions of the world.

  13. Visual field

    MedlinePlus

    Perimetry; Tangent screen exam; Automated perimetry exam; Goldmann visual field exam; Humphrey visual field exam ... Confrontation visual field exam : This is a quick and basic check of the visual field. The health care provider ...

  14. The South Carolina bridge-scour envelope curves

    USGS Publications Warehouse

    Benedict, Stephen T.; Feaster, Toby D.; Caldwell, Andral

    2016-09-30

    The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations to evaluate historical, riverine bridge scour in the Piedmont and Coastal Plain regions of South Carolina. These investigations included data collected at 231 riverine bridges, which lead to the development of bridge-scour envelope curves for clear-water and live-bed components of scour. The application and limitations of the South Carolina bridge-scour envelope curves were documented in four reports, each report addressing selected components of bridge scour. The current investigation (2016) synthesizes the findings of these previous reports into a guidance manual providing an integrated procedure for applying the envelope curves. Additionally, the investigation provides limited verification for selected bridge-scour envelope curves by comparing them to field data collected outside of South Carolina from previously published sources. Although the bridge-scour envelope curves have limitations, they are useful supplementary tools for assessing the potential for scour at riverine bridges in South Carolina.

  15. South Polar Knob

    NASA Technical Reports Server (NTRS)

    2005-01-01

    1 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small, relatively light-toned knob of layered material, and the erosional expression of the underlying layers, in the south polar region of Mars. When the image was acquired in April 2005, the surface was still covered with seasonal carbon dioxide frost. Dark spots and streaks mark locations where the frost had begun to change and sublime away.

    Location near: 84.2oS, 138.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season Southern Spring