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Sample records for pilot horizontal subsurface

  1. Effects of tidal operation on pilot-scale horizontal subsurface flow constructed wetland treating sulfate rich wastewater contaminated by chlorinated hydrocarbons.

    PubMed

    Chen, Zhongbing; Vymazal, Jan; Kuschk, Peter

    2017-01-01

    Three different flow regimes were carried out in a pilot-scale horizontal subsurface flow constructed wetland-treating sulfate rich wastewater contaminated with monochlorobenzene (MCB) and perchloroethene (PCE). The three regimes were continuous flow, 7-day cycle discontinuous flow, and 2.5-day cycle discontinuous flow. The results show that intensifying the tidal regime (2.5-day cycle) significantly enhanced MCB removal before 2 m from the inlet and increasing PCE removal efficiency at 0.5 m. The PCE dechlorination process was promoted with tidal operation, especially under the 2.5-day cycle regime, with significant increases of cis-1,2- dichloroethenes (DCEs), vinyl chloride (VC), and ethene, but trans-1,2-DCE was significantly decreased after tidal operation. Due to the high sulfate concentration in the influent, sulfide was observed in pore water up to 20 and 23 mg L(-1) under continuous flow and 7-day cycle regime, respectively. However, sulfide concentrations decreased to less than 4 mg L(-1) under intensified tidal operation (2.5-day cycle). The increase of oxygen concentration in pore water through intensified tidal operation resulted in better MCB removal performance and the successful inhibition of sulfate reduction. In conclusion, intensifying tidal operation is an effective approach for the treatment of chlorinated hydrocarbons and inhibiting sulfide accumulation in horizontal subsurface flow constructed wetland.

  2. Temporal and spatial variations of contaminant removal, enzyme activities, and microbial community structure in a pilot horizontal subsurface flow constructed wetland purifying industrial runoff.

    PubMed

    Yi, Xiao-Hui; Jing, Dan-Dan; Wan, Jinquan; Ma, Yongwen; Wang, Yan

    2016-05-01

    A pilot-scale horizontal subsurface flow constructed wetland (HSSFCW) was operated to purify industrial runoff containing polycyclic aromatic hydrocarbons (PAHs) in Guangzhou, China. Synthetic industrial runoff was fed into the HSSFCW with continuous flow at an average loading rate of 0.128 m(3)/(m(2)/day) for about 2 years. Pollutants such as chemical oxygen demand (COD), total phosphorus (TP), and phenanthrene were mainly removed in the front quarter of the HSSFCW, and in the vertical direction, the average removal rates of COD, TP, total nitrogen (TN), ammonia, and phenanthrene of the upper layer were 64.23, 71.16, 50.81, 65.38, and 92.47 %, which were 1.23, 2.08, 1.48, 1.72, and 1.17 times higher than those of the bottom, respectively. Correlations among pollutant removal, soil environmental indexes, enzyme activities, and soil microbial community structure were evaluated. Enzyme assays (dehydrogenase, catalase, nitrate reductase, and polyphenol oxidase) showed significant associations between enzyme activities and pollutant removal (p < 0.01 and p < 0.05). Soil microbial community structure was assessed with denaturing gradient gel electrophoresis (DGGE) fingerprinting method, and results demonstrated that bacterial communities remained relatively stable in different seasons. Proteobacteria and Bacteroidetes were found to be the dominant phyla of the bacteria communities, and three clones which might be related to the biodegradation of phenanthrene were also detected. Results of the present work would broaden the knowledge of the purification mechanism of contaminants in the constructed wetlands (CWs), and identification of the treatment performances and temporal and spatial variations of biological activities of subsurface flow constructed wetlands (SSFCWs) would help to improve the operations of CWs for surface water protection.

  3. Treatment of a sulfate-rich groundwater contaminated with perchloroethene in a hydroponic plant root mat filter and a horizontal subsurface flow constructed wetland at pilot-scale.

    PubMed

    Chen, Zhongbing; Kuschk, Peter; Paschke, Heidrun; Kästner, Matthias; Müller, Jochen A; Köser, Heinz

    2014-12-01

    A hydroponic plant root mat filter (HPRMF) was compared over 7months with a horizontal subsurface flow constructed wetland (HSSF CW) regarding the removal of perchloroethene (PCE) (about 2 mg L(-1)) from a sulfate- (850 mg L(-1)) and ammonia-rich (50 mg L(-1)) groundwater with a low TOC content. At a mean area specific inflow PCE load of 56 mg m(-2)d(-1), after 4m from inlet, the mean PCE removal during summer time reached 97% in the HPRMF and almost 100% in the HSSF CW. Within the first 2m in the HSSF CW metabolites like dichloroethenes, vinyl chloride and ethene accumulated, their concentrations decreased further along the flow path. Moreover, the tidal operation (a 7-d cycle) in the HSSFCW decreased the accumulation of PCE metabolites within the first 1m of the bed. The carcinogenic degradation metabolite vinyl chloride was not detected in the HPRMF. The smaller accumulation of the degradation metabolites in the HPRMF correlated with its higher redox potential. It can be concluded from this study that HPRMF appears an interesting alternative for special water treatment tasks and that tidal operation will show some positive effects on the removal of the accumulated PCE metabolites in HSSF CW.

  4. DIVERGENT HORIZONTAL SUB-SURFACE FLOWS WITHIN ACTIVE REGION 11158

    SciTech Connect

    Jain, Kiran; Tripathy, S. C.; Hill, F. E-mail: stripathy@nso.edu

    2015-07-20

    We measure the horizontal subsurface flow in a fast emerging active region (AR; NOAA 11158) using the ring-diagram technique and the Helioseismic and Magnetic Imager high spatial resolution Dopplergrams. This AR had a complex magnetic structure and displayed significant changes in morphology during its disk passage. Over a period of six days from 2011 February 11 to 16, the temporal variation in the magnitude of the total velocity is found to follow the trend of magnetic field strength. We further analyze regions of individual magnetic polarity within AR 11158 and find that the horizontal velocity components in these sub-regions have significant variation with time and depth. The leading and trailing polarity regions move faster than the mixed-polarity region. Furthermore, both zonal and meridional components have opposite signs for trailing and leading polarity regions at all depths showing divergent flows within the AR. We also find a sharp decrease in the magnitude of total horizontal velocity in deeper layers around major flares. It is suggested that the re-organization of magnetic fields during flares, combined with the sunspot rotation, decreases the magnitude of horizontal flows or that the flow kinetic energy has been converted into the energy released by flares. After the decline in flare activity and sunspot rotation, the flows tend to follow the pattern of magnetic activity. We also observe less variation in the velocity components near the surface but these tend to increase with depth, further demonstrating that the deeper layers are more affected by the topology of ARs.

  5. Evaluation of unclogging aspects in horizontal subsurface flow constructed wetlands.

    PubMed

    Miranda, Suymara Toledo; de Matos, Antonio Teixeira; Baptestini, Gheila Corrêa Ferres; Borges, Alisson Carraro

    2016-10-01

    In horizontal subsurface flow constructed wetlands (HSSF-CWs), the main operational problem is clogging of the porous medium. In this study, the unclogging of HSSF-CWs was evaluated, at rest, by adding a nitrogen-based nutrient solution to the influent. For this, six HSSF-CWs were used, consisting of two uncultivated (CW-C), two cultivated with Tifton 85-grass (Cynodon spp.) (CW-T) and two cultivated with alligator weed (Alternanthera philoxeroides) (CW-A), which were fully clogged after being used for the treatment of swine wastewater. The results indicated that passage of the nutrient solution for 55 days through the bed of the HSSF-CWs resulted in reductions of 11 and 33%, respectively, in the total volatile solids (TVS) concentration of fine clogging material in the CW-T and CW-A. With regard to the TVS content of the coarse clogging material, the reduction was even greater, being 33% for CW-T and 62% for CW-A. Measurements of K0 made along the beds (thirds 1, 2 and 3) before and after passage of the nutrient solution in the CWs indicated respective increases of 7, 13 and 0.1% in CW-C; 21, 11 and 7% in CW-T; and 52%, 6% and -6% (decrease) in CW-A. Runoff of the nutrient solution decreased gradually over time, presenting at the beginning of the experiment 26, 35 and 150 cm, and at the end (after 55 days of application) 0, 0 and 50 cm in the flow direction of the CW-C and CW-T and CW-A, respectively.

  6. Horizontal canal benign paroxysmal positional vertigo in a fighter pilot

    PubMed Central

    Xie, Su-Jiang; Wang, Jiang-Chang; Ding, Li; Sun, Xi-Qing

    2011-01-01

    Benign paroxysmal positional vertigo (BPPV) is the most common disorder of the peripheral vestibular system, characterized by intense, positional provoked vertigo. BPPV is thought to occur due to canalithiasis of the posterior semicircular canal. Recently, a new entity of BPPV, known as horizontal canal (HC)-BPPV, has been recognized. Although only 3 to 8% of BPPV is due to horizontal canal involvement, HC-BPPV is not rare. We present a case of a naval fighter pilot who had an incident of HC-BPPV on the ground. The pilot aeromedical evaluation and considerations are discussed. PMID:21716841

  7. Horizontal canal benign paroxysmal positional vertigo in a fighter pilot.

    PubMed

    Xie, Su-Jiang; Wang, Jiang-Chang; Ding, Li; Sun, Xi-Qing

    2011-01-01

    Benign paroxysmal positional vertigo (BPPV) is the most common disorder of the peripheral vestibular system, characterized by intense, positional provoked vertigo. BPPV is thought to occur due to canalithiasis of the posterior semicircular canal. Recently, a new entity of BPPV, known as horizontal canal (HC)-BPPV, has been recognized. Although only 3 to 8% of BPPV is due to horizontal canal involvement, HC-BPPV is not rare. We present a case of a naval fighter pilot who had an incident of HC-BPPV on the ground. The pilot aeromedical evaluation and considerations are discussed.

  8. Influence of chlorothalonil on the removal of organic matter in horizontal subsurface flow constructed wetlands.

    PubMed

    Casas-Zapata, Juan C; Ríos, Karina; Florville-Alejandre, Tomás R; Morató, Jordi; Peñuela, Gustavo

    2013-01-01

    This study investigates the effects of chlorothalonil (CLT) on chemical oxygen demand (COD) and dissolved organic carbon (DOC) in pilot-scale horizontal subsurface flow constructed wetlands (HSSFCW) planted with Phragmites australis. Physicochemical parameters of influent and effluent water samples, microbial population counting methods and statistical analysis were used to evaluate the influence of CLT on organic matter removal efficiency. The experiments were conducted on four planted replicate wetlands (HSSFCW-Pa) and one unplanted control wetland (HSSFCW-NPa). The wetlands exhibited high average organic matter removal efficiencies (HSSFCW-Pa: 80.6% DOC, 98.0% COD; HSSFCW-NPa: 93.2% DOC, 98.4% COD). The addition of CLT did not influence organic removal parameters. In all cases CLT concentrations in the effluent occurred in concentrations lower than the detection limit of the analytical method. Microbial population counts from HSSFCW-Pa showed significant correlations among different microbial groups and with different physicochemical variables. The apparent independence of organic matter removal and CLT inputs, along with the CLT depletion observed in effluent samples demonstrated that HSSFCW are a viable technology for the treatment of agricultural effluents contaminated with organo-chloride pesticides like CLT.

  9. Optimal conditions for chlorothalonil and dissolved organic carbon in horizontal subsurface flow constructed wetlands.

    PubMed

    Rìos-Montes, Karina A; Casas-Zapata, Juan C; Briones-Gallardo, Roberto; Peñuela, Gustavo

    2017-01-13

    The most efficient system of horizontal subsurface flow constructed wetlands (HSSFCW) for removing dissolved organic carbon (DOC) in the presence of chlorothalonil pesticide (CLT) present in synthetic domestic wastewater was determined using the macrophyte Phragmites australis. Two concentrations of CLT (85 and 385 μg L(-1)) and one concentration of glucose (20 mg L(-1)) were evaluated in four pilot scale horizontal surface flow constructed wetlands coupled with two sizes of silica gravel, igneous gravel, fine chalky gravel (3.18-6.35 mm), coarse gravel (12.70-25.40 mm) and two water surface heights (20 and 40 cm). For a month, wetlands were acclimated with domestic wastewater. Some groups of bacteria were also identified in the biofilm attached to the gravel. In each treatment periodic samplings were conducted in the influent and effluent. Chlorothalonil was quantified by gas chromatography (GC-ECD m), DOC by an organic carbon analyzer and bacterial groups using conventional microbiology in accordance with Standard Methods. The largest removals of DOC (85.82%-85.31%) were found when using fine gravel (3.18-6.35 mm) and the lower layer of water (20 cm). The bacterial groups quantified in the biofilm were total heterotrophic, revivable heterotrophic, Pseudomonas and total coliforms. The results of this study indicate that fine grain gravel (3.18-6.35 mm) and both water levels (20 to 40 cm) can be used in the removal of organic matter and for the treatment of agricultural effluents contaminated with organo-chloride pesticides like CLT in HSSFCW.

  10. BPA and NP removal from municipal wastewater by tropical horizontal subsurface constructed wetlands.

    PubMed

    Toro-Vélez, A F; Madera-Parra, C A; Peña-Varón, M R; Lee, W Y; Bezares-Cruz, J C; Walker, W S; Cárdenas-Henao, H; Quesada-Calderón, S; García-Hernández, H; Lens, P N L

    2016-01-15

    It has been recognized that numerous synthetic compounds like Bisphenol A (BPA) and nonylphenols (NP) are present in effluents from wastewater treatment plants (WWTP) at levels of parts per billion (μg L(-1)) or even parts per trillion (ng L(-1)) with a high potential to cause endocrine disruption in the aquatic environment. Constructed wetlands (CW) are a cost-effective wastewater treatment alternative with promising performance to treat these afore mentioned compounds. This research was aimed to evaluate the efficacy of CW treatment of WWTP effluent for mitigating the effects endocrine disrupting compounds (EDCs). This research goal was accomplished by (1) quantifying the removal of BPA and NP in CWs; (2) isolating CW fungal strains and testing for laccase production; and (3) performing endocrine disruption (reproduction) bioassays using the fruit fly Drosophila melanogaster. Three pilot scale horizontal subsurface flow constructed wetlands (HSSF-CW) were operated for eight weeks: one planted with Phragmites australis; one planted with Heliconia psitacorum; and one unplanted. The Heliconia CW showed a removal efficiency of 73.3(± 19%) and 62.8(± 20.1%) for BPA and NP, respectively; while the Phragmites CW demonstrated a similar removal for BPA (70.2 ± 27%) and lower removal efficiency for NP 52.1(± 37.1%).The unplanted CW achieved 62.2 (± 33%) removal for BPA and 25.3(± 37%) removal for NP. Four of the eleven fungal strains isolated from the Heliconia-CW showed the capacity to produce laccase. Even though complete removal of EDCs was not achieved by the CWs, the bioassay confirmed a significant improvement (p < 0.05) in fly viability for all CWs, with Heliconia sp. being the most effective at mitigating adverse effects on first and second generational reproduction. This study showed that a CW planted with a native Heliconia sp. CW demonstrated a higher removal of endocrine disrupting compounds and better mitigation of reproductive disruption in the

  11. Potential for horizontal gene transfer in microbial communities of the terrestrial subsurface.

    PubMed

    Coombs, Jonna M

    2009-01-01

    The deep terrestrial subsurface is a vast, largely unexplored environment that is oligotrophic, highly heterogeneous, and may contain extremes of both physical and chemical factors. In spite of harsh conditions, subsurface studies at several widely distributed geographic sites have revealed diverse communities of viable organisms, which have provided evidence of low but detectable metabolic activity. Although much of the terrestrial subsurface may be considered to be distant and isolated, the concept of horizontal gene transfer (HGT) in this environment has far-reaching implications for bioremediation efforts and groundwater quality, industrial harvesting of subsurface natural resources such as petroleum, and accurate assessment of the risks associated with DNA release and transport from genetically modified organisms. This chapter will explore what is known about some of the major mechanisms of HGT, and how the information gained from surface organisms might apply to conditions in the terrestrial subsurface. Evidence for the presence of mobile elements in subsurface bacteria and limited retrospective studies examining genetic signatures of potential past gene transfer events will be discussed.

  12. Evapotranspiration from subsurface horizontal flow wetlands planted with Phragmites australis in sub-tropical Australia.

    PubMed

    Headley, T R; Davison, L; Huett, D O; Müller, R

    2012-02-01

    The balance between evapotranspiration (ET) loss and rainfall ingress in treatment wetlands (TWs) can affect their suitability for certain applications. The aim of this paper was to investigate the water balance and seasonal dynamics in ET of subsurface horizontal flow (HF) TWs in a sub-tropical climate. Monthly water balances were compiled for four pilot-scale HF TWs receiving horticultural runoff over a two year period (Sep. 1999-Aug. 2001) on the sub-tropical east-coast of Australia. The mean annual wetland ET rate increased from 7.0 mm/day in the first year to 10.6 mm/day in the second, in response to the development of the reed (Phragmites australis) population. Consequently, the annual crop coefficients (ratio of wetland ET to pan evaporation) increased from 1.9 in the first year to 2.6 in the second. The mean monthly ET rates were generally greater and more variable than the Class-A pan evaporation rates, indicating that transpiration is an important contributor to ET in HF TWs. Evapotranspiration rates were generally highest in the summer and autumn months, and corresponded with the times of peak standing biomass of P. australis. It is likely that ET from the relatively small 1 m wide by 4 m long HF TWs was enhanced by advection through so-called "clothesline" and "oasis" effects, which contributed to the high crop coefficients. For the second year, when the reed population was well established, the annual net loss to the atmosphere (taking into account rainfall inputs) accounted for 6.1-9.6 % of the influent hydraulic load, which is considered negligible. However, the net loss is likely to be higher in arid regions with lower rainfall. The Water Use Efficiency (WUE) of the wetlands in the second year of operation was 1.3 g of above-ground biomass produced per kilogram of water consumed, which is low compared to agricultural crops. It is proposed that system level WUE provides a useful metric for selecting wetland plant species and TW design alternatives to

  13. SST Control by Subsurface Mixing during Indian Ocean Monsoons: 1-yr Pilot Project

    DTIC Science & Technology

    2013-09-30

    public release; distribution is unlimited. SST Control by Subsurface Mixing during Indian Ocean Monsoons : 1-yr Pilot Project Emily Shroyer and James...observational basis and physical interpretation for new mixing parameterizations that will contribute to improved monsoon predictions in this sensitive...4. TITLE AND SUBTITLE SST Control by Subsurface Mixing during Indian Ocean Monsoons : 1-yr Pilot Project 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  14. Adjustable recessions in horizontal comitant strabismus: A pilot study

    PubMed Central

    Agrawal, Siddharth; Singh, Vinita; Singh, Priyanka

    2015-01-01

    Aim: To compare the surgical outcome of adjustable with the conventional recession in patients with horizontal comitant strabismus. Patients and Methods: A prospective comparative nonrandomized interventional pilot study was performed on patients with horizontal comitant strabismus. Fifty-four patients (27 in each group) were allocated into 2 groups to undergo either adjustable suture (AS) recession or non-AS (NAS) recession along with conventional resection. The patients were followed up for 6 months. A successful outcome was defined as deviation ±10 prism diopters at 6 months. The results were statistically analyzed by Chi-square test, Fisher's exact test, and Student's t-test. Results: A successful outcome was found in 24 (88.8%) patients in AS and 17 (62.9%) in NAS group (P = 0.02). The postoperative adjustment was done in 13 (48.1%) patients in AS group. There was one complication (tenon's cyst) in AS group. Conclusion: AS recession may be considered in all cooperative patients undergoing strabismus surgery for comitant deviations. PMID:26458480

  15. Single cell genomics indicates horizontal gene transfer and viral infections in a deep subsurface Firmicutes population

    PubMed Central

    Labonté, Jessica M.; Field, Erin K.; Lau, Maggie; Chivian, Dylan; Van Heerden, Esta; Wommack, K. Eric; Kieft, Thomas L.; Onstott, Tullis C.; Stepanauskas, Ramunas

    2015-01-01

    A major fraction of Earth's prokaryotic biomass dwells in the deep subsurface, where cellular abundances per volume of sample are lower, metabolism is slower, and generation times are longer than those in surface terrestrial and marine environments. How these conditions impact biotic interactions and evolutionary processes is largely unknown. Here we employed single cell genomics to analyze cell-to-cell genome content variability and signatures of horizontal gene transfer (HGT) and viral infections in five cells of Candidatus Desulforudis audaxviator, which were collected from a 3 km-deep fracture water in the 2.9 Ga-old Witwatersrand Basin of South Africa. Between 0 and 32% of genes recovered from single cells were not present in the original, metagenomic assembly of Desulforudis, which was obtained from a neighboring subsurface fracture. We found a transposable prophage, a retron, multiple clustered regularly interspaced short palindromic repeats (CRISPRs) and restriction-modification systems, and an unusually high frequency of transposases in the analyzed single cell genomes. This indicates that recombination, HGT and viral infections are prevalent evolutionary events in the studied population of microorganisms inhabiting a highly stable deep subsurface environment. PMID:25954269

  16. Monitoring radionuclides in subsurface drinking water sources near unconventional drilling operations: a pilot study.

    PubMed

    Nelson, Andrew W; Knight, Andrew W; Eitrheim, Eric S; Schultz, Michael K

    2015-04-01

    Unconventional drilling (the combination of hydraulic fracturing and horizontal drilling) to extract oil and natural gas is expanding rapidly around the world. The rate of expansion challenges scientists and regulators to assess the risks of the new technologies on drinking water resources. One concern is the potential for subsurface drinking water resource contamination by naturally occurring radioactive materials co-extracted during unconventional drilling activities. Given the rate of expansion, opportunities to test drinking water resources in the pre- and post-fracturing setting are rare. This pilot study investigated the levels of natural uranium, lead-210, and polonium-210 in private drinking wells within 2000 m of a large-volume hydraulic fracturing operation--before and approximately one-year following the fracturing activities. Observed radionuclide concentrations in well waters tested did not exceed maximum contaminant levels recommended by state and federal agencies. No statistically-significant differences in radionuclide concentrations were observed in well-water samples collected before and after the hydraulic fracturing activities. Expanded monitoring of private drinking wells before and after hydraulic fracturing activities is needed to develop understanding of the potential for drinking water resource contamination from unconventional drilling and gas extraction activities.

  17. Bacterial transformation and biodegradation processes simulation in horizontal subsurface flow constructed wetlands using CWM1-RETRASO.

    PubMed

    Llorens, Esther; Saaltink, Maarten W; Poch, Manel; García, Joan

    2011-01-01

    The performance and reliability of the CWM1-RETRASO model for simulating processes in horizontal subsurface flow constructed wetlands (HSSF CWs) and the relative contribution of different microbial reactions to organic matter (COD) removal in a HSSF CW treating urban wastewater were evaluated. Various different approaches with diverse influent configurations were simulated. According to the simulations, anaerobic processes were more widespread in the simulated wetland and contributed to a higher COD removal rate [72-79%] than anoxic [0-1%] and aerobic reactions [20-27%] did. In all the cases tested, the reaction that most contributed to COD removal was methanogenesis [58-73%]. All results provided by the model were in consonance with literature and experimental field observations, suggesting a good performance and reliability of CWM1-RETRASO. According to the good simulation predictions, CWM1-RETRASO is the first mechanistic model able to successfully simulate the processes described by the CWM1 model in HSSF CWs.

  18. The Cartridge Theory: a description of the functioning of horizontal subsurface flow constructed wetlands for wastewater treatment, based on modelling results.

    PubMed

    Samsó, Roger; García, Joan

    2014-03-01

    Despite the fact that horizontal subsurface flow constructed wetlands have been in operation for several decades now, there is still no clear understanding of some of their most basic internal functioning patterns. To fill this knowledge gap, on this paper we present what we call "The Cartridge Theory". This theory was derived from simulation results obtained with the BIO_PORE model and explains the functioning of urban wastewater treatment wetlands based on the interaction between bacterial communities and the accumulated solids leading to clogging. In this paper we start by discussing some changes applied to the biokinetic model implemented in BIO_PORE (CWM1) so that the growth of bacterial communities is consistent with a well-known population dynamics models. This discussion, combined with simulation results for a pilot wetland system, led to the introduction of "The Cartridge Theory", which states that the granular media of horizontal subsurface flow wetlands can be assimilated to a generic cartridge which is progressively consumed (clogged) with inert solids from inlet to outlet. Simulations also revealed that bacterial communities are poorly distributed within the system and that their location is not static but changes over time, moving towards the outlet as a consequence of the progressive clogging of the granular media. According to these findings, the life-span of constructed wetlands corresponds to the time when bacterial communities are pushed as much towards the outlet that their biomass is not anymore sufficient to remove the desirable proportion of the influent pollutants.

  19. Vertical Subsurface Flow Mixing and Horizontal Anisotropy in Coarse Fluvial Aquifers: Structural Aspects

    NASA Astrophysics Data System (ADS)

    Huggenberger, P.; Huber, E.

    2014-12-01

    Detailed descriptions of the subsurface heterogeneities in coarse fluvial aquifer gravel often lack in concepts to distinguish between the essence and the noise of a permeability structure and the ability to extrapolate site specific hydraulic information at the tens to several hundred meters scale. At this scale the heterogeneity strongly influences the anisotropies of the flow field and the mixing processes in groundwater. However, in many hydrogeological models the complexity of natural systems is oversimplified. Understanding the link between the dynamics of the surface processes of braided-river systems and the resulting subsurface sedimentary structures is the key to characterizing the complexity of horizontal and vertical mixing processes in groundwater. From the different depositional elements of coarse braided-river systems, the largest permeability contrasts can be observed in the scour-fills. Other elements (e.g. different types of gravel sheets) show much smaller variabilities and could be considered as a kind of matrix. Field experiments on the river Tagliamento (Northeast Italy) based on morphological observation and ground-penetrating radar (GPR) surveys, as well as outcrop analyses of gravel pit exposures (Switzerland) allowed us to define the shape, sizes, spatial distribution and preservation potential of scour-fills. In vertical sections (e.g. 2D GPR data, vertical outcrop), the spatial density of remnant erosional bounding surfaces of scours is an indicator for the dynamics of the braided-river system (lateral mobility of the active floodplain, rate of sediment net deposition and spatial distribution of the confluence scours). In case of combined low aggradation rate and low lateral mobility the deposits may be dominated by a complex overprinting of scour-fills. The delineation of the erosional bounding surfaces, that are coherent over the survey area, is based on the identification of angular discontinuities of the reflectors. Fence diagrams

  20. Numerical simulation for horizontal subsurface flow constructed wetlands: A short review including geothermal effects and solution bounding in biodegradation procedures

    NASA Astrophysics Data System (ADS)

    Liolios, K.; Tsihrintzis, V.; Angelidis, P.; Georgiev, K.; Georgiev, I.

    2016-10-01

    Current developments on modeling of groundwater flow and contaminant transport and removal in the porous media of Horizontal Subsurface Flow Constructed Wetlands (HSF CWs) are first reviewed in a short way. The two usual environmental engineering approaches, the black-box and the process-based one, are briefly presented. Next, recent research results obtained by using these two approaches are briefly discussed as application examples, where emphasis is given to the evaluation of the optimal design and operation parameters concerning HSF CWs. For the black-box approach, the use of Artificial Neural Networks is discussed for the formulation of models, which predict the removal performance of HSF CWs. A novel mathematical prove is presented, which concerns the dependence of the first-order removal coefficient on the Temperature and the Hydraulic Residence Time. For the process-based approach, an application example is first discussed which concerns procedures to evaluate the optimal range of values for the removal coefficient, dependent on either the Temperature or the Hydraulic Residence Time. This evaluation is based on simulating available experimental results of pilot-scale units operated in Democritus University of Thrace, Xanthi, Greece. Further, in a second example, a novel enlargement of the system of Partial Differential Equations is presented, in order to include geothermal effects. Finally, in a third example, the case of parameters uncertainty concerning biodegradation procedures is considered and the use of upper and a novel approach is presented, which concerns the upper and the lower solution bound for the practical draft design of HSF CWs.

  1. Effects of intermittent loading on nitrogen removal in horizontal subsurface flow wetlands.

    PubMed

    Forbes, Margaret G; Yelderman, Joe C; Potterton, Tina; Doyle, Robert D

    2010-01-01

    Removal of CBOD(5) and nitrogen from septic tank effluent was evaluated in four horizontal subsurface flow (HSSF) wetlands. An intermittently loaded cell was compared to a continuously loaded control cell, with both treatments receiving the same weekly volume. The intermittent cell was rapidly drained and "rested" for 24-hr, then refilled in steps, twice weekly. Two media with different particle sizes but similar porosities were also compared. The two media, light weight expanded shale and gravel, were both continuously loaded. As hypothesized, the wetland cell that was intermittently loaded had higher dissolved oxygen, greater ammonia removal, and greater nitrate production than the continuously loaded cells. Areal NH(3)-N removal for the intermittently loaded cell was 0.90 g m(-2) d(-1) compared to 0.47 g m(-2) d(-1) for the control. Ammonia removal was also higher in continuously loaded gravel cells than in cells with expanded shale. Ammonia-N removal was an order of magnitude lower in a similar SSF wetland that had been in operation for 3 years. However, CBOD(5), total suspended solids, and total nitrogen did not vary substantially among the treatments.

  2. Clogging development and hydraulic performance of the horizontal subsurface flow stormwater constructed wetlands: a laboratory study.

    PubMed

    Tang, Ping; Yu, Bohai; Zhou, Yongchao; Zhang, Yiping; Li, Jin

    2017-02-21

    The horizontal subsurface constructed wetland (HSSF CW) is a highly effective technique for stormwater treatment. However, progressive clogging in HSSF CW is a widespread operational problem. The aim of this study was to understand the clogging development of HSSF CWs during stormwater treatment and to assess the influence of microorganisms and vegetation on the clogging. Moreover, the hydraulic performance of HSSF CWs in the process of clogging was evaluated in a tracer experiment. The results show that the HSSF CW can be divided into two sections, section I (circa 0-35 cm) and section II (circa 35-110 cm). The clogging is induced primarily by solid entrapment in section I and development of biofilm and vegetation roots in section II, respectively. The influence of vegetation and microorganisms on the clogging appears to differ in sections I and II. The tracer experiment shows that the hydraulic efficiency (λ) and the mean hydraulic retention time (t mean) increase with the clogging development; although, the short-circuiting region (S) extends slightly. In addition, the presence of vegetation can influence the hydraulic performance of the CWs, and their impact depends on the characteristics of the roots.

  3. Use of horizontal subsurface flow constructed wetlands to treat reverse osmosis concentrate of rolling wastewater.

    PubMed

    Xu, Jingcheng; Zhao, Gang; Huang, Xiangfeng; Guo, Haobo; Liu, Wei

    2017-03-04

    According to the characteristics of the reverse osmosis concentrate (ROC) generated from iron and steel company, we used three sets of parallel horizontal subsurface flow (HSF) constructed wetlands (CWs) with different plants and substrate layouts to treat the high-salinity wastewater. The plant growth and removal efficiencies under saline condition were evaluated. The evaluation was based entirely on routinely collected water quality data and the physical and chemical characteristics of the plants (Phragmites australis, Typha latifolia, Iris wilsonii, and Scirpus planiculmis). The principal parameters of concern in the effluent were chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP). The results showed that the CWs were able to remove COD, TN, and TP from ROC. S. planiculmis was not suitable for the treatment of high-saline wastewater. The sequence of metals accumulated in CW plants was K>Ca>Na>Mg>Zn>Cu. More than 70% of metals were accumulated in the aboveground of P. australis. The CW filled with gravel and manganese ore and planted with P. australis and T. latifolia had the best performance of pollutant removal, with average removal of 49.96%, 39.45%, and 72.01% for COD, TN, and TP, respectively. The effluent water quality met the regulation in China. These results suggested that HSF CW planted with P. australis and T. latifolia can be applied for ROC pollutants removal.

  4. Performance of experimental horizontal subsurface flow constructed wetlands fed with dissolved or particulate organic matter.

    PubMed

    Caselles-Osorio, Aracelly; García, Joan

    2006-11-01

    In this study, the effect of the influent type of organic matter (dissolved or particulate) on the efficiency of two experimental horizontal subsurface flow constructed wetlands (SSF CWs) was investigated. The SSF CWs' surface area was 0.54 m(2) and the water depth was 0.3m. They were monitored for a period of 9 months. One of the SSF CWs was fed with dissolved organic matter (glucose, assumed to be readily biodegradable), and the other with particulate organic matter (starch, assumed to be slowly biodegradable). The removal efficiency of the systems was tested at different hydraulic retention times (HRTs) in the presence or absence of sulphate. The removal efficiency of the COD was not different in the two systems, reaching eliminations of around 85% in the presence of sulphates and around 95% in their absence. Ammonia N removal was low in the two SSF CWs; the system fed with glucose generally had statistically significant higher removal (45%) than the one fed with starch (40%). Ammonia N removal was more affected by the HRT than by the presence or absence of sulphates. Hydraulic conductivity measurements showed that it was lower near the inlet of the SFF CW fed with glucose, probably connected to the fact that there was a more substantial development of the biofilm. The results of this study suggest that SSF CWs are not sensitive to the type of organic matter in the influents, whether it is readily (like glucose) or slowly (like starch) biodegradable, for the removal of COD.

  5. Horizontal Transfer of Tetracycline Resistance Genes in the Subsurface of a Poultry Farm

    NASA Astrophysics Data System (ADS)

    You, Y.; Ward, M.; Hilpert, M.

    2008-12-01

    Concentrated animal feeding operations (CAFOs) are considered to be important man-made reservoirs of antibiotic resistant bacteria and antibiotic resistance genes. At a poultry farm, we, together with Mr.~James Doolittle from USDA, measured the apparent subsurface electrical conductivity (ECa) using a EM38 meter. The resulting ECaR) associated with the poultry farm due to the fact that tetracycline (Tc) is one of the most frequently used antibiotics in food animal production and therefore is probably used at this farm. Soil and aquifer samples were taken from the farm. TcR bacteria were detected, with higher concentrations in the top layer of soil than in the aquifer. TcR bacteria were then enriched from a soil sample, and two classes of TcR genes were detected: tet(M) genes encoding ribosomal protection proteins and tet(L) genes encoding tet efflux pumps. Sequences of the PCR products were compared to known tet(M) and tet(L) genes in GenBank using BLASTN. Phylogenetic trees were also built based on the sequence information. The tet(M) genes found in our soil sample were highly similar to those located on transposons. In a soil microcosm experiment, we used the aforementioned soil sample as incubation medium as well as genetic donor (TcR soil bacteria), and a green fluorescent strain of E. coli as a model genetic recipient to study horizontal transfer of TcR genes from soil bacteria to naïve bacteria. Concentrations of inoculated E. coli were continuously monitored for 15 days, TcR E. coli isolated, and colony PCR performed. The tet(M) genes were found to be transferred to naïve E. coli. The highest horizontal transfer ratio, 0.62 transconjugant per recipient, was observed when Tc was supplemented to a soil microcosm at a concentration of 140 μg/kg soil. Modeling is also ongoing to obtain a better understanding of this complex phenomenon.

  6. Biological mechanisms associated with triazophos (TAP) removal by horizontal subsurface flow constructed wetlands (HSFCW).

    PubMed

    Wu, Juan; Feng, Yuqin; Dai, Yanran; Cui, Naxin; Anderson, Bruce; Cheng, Shuiping

    2016-05-15

    Triazophos (TAP) is a widely used pesticide that is easily accumulated in the environment due to its relatively high stability: this accumulation from agricultural runoff results in potential hazards to aquatic ecosystems. Constructed wetlands are generally considered to be an effective technology for treating TAP polluted surface water. However, knowledge about the biological mechanisms of TAP removal is still lacking. This study investigates the responses of a wetland plant (Canna indica), substrate enzymes and microbial communities in bench-scale horizontal subsurface-flow constructed wetlands (HSCWs) loaded with different TAP concentrations (0, 0.1, 0.5 and 5 mg · L(-1)). The results indicate that TAP stimulated the activities of superoxide dismutase (SOD) and peroxidase (POD) in the roots of C. indica. The highest TAP concentrations significantly inhibited photosynthetic activities, as shown by a reduced effective quantum yield of PS II (ΦPS II) and lower electron transport rates (ETR). However, interestingly, the lower TAP loadings exhibited some favorable effects on these two variables, suggesting that C. indica is a suitable species for use in wetlands designed for treatment of low TAP concentrations. Urease and alkaline phosphatase (ALP) in the wetland substrate were activated by TAP. Two-way ANOVA demonstrated that urease activity was influenced by both the TAP concentrations and season, while acidphosphatase (ACP) only responded to seasonal variations. Analysis of high throughput sequencing of 16S rRNA revealed seasonal variations in the microbial community structure of the wetland substrate at the phylum and family levels. In addition, urease activity had a greater correlation with the relative abundance of some functional microbial groups, such as the Bacillaceae family, and the ALP and ACP may be influenced by the plant more than substrate microbial communities.

  7. Horizontal Gene Transfer of PIB-Type ATPases among Bacteria Isolated from Radionuclide- and Metal-Contaminated Subsurface Soils

    PubMed Central

    Martinez, Robert J.; Wang, Yanling; Raimondo, Melanie A.; Coombs, Jonna M.; Barkay, Tamar; Sobecky, Patricia A.

    2006-01-01

    Aerobic heterotrophs were isolated from subsurface soil samples obtained from the U.S. Department of Energy's (DOE) Field Research Center (FRC) located at Oak Ridge, Tenn. The FRC represents a unique, extreme environment consisting of highly acidic soils with cooccurring heavy metals, radionuclides, and high nitrate concentrations. Four hundred isolates obtained from contaminated soil were assayed for heavy metal resistance, and a smaller subset was assayed for tolerance to uranium. The vast majority of the isolates were gram-positive bacteria and belonged to the high-G+C- and low-G+C-content genera Arthrobacter and Bacillus, respectively. Genomic DNA from a randomly chosen subset of 50 Pb-resistant (Pbr) isolates was amplified with PCR primers specific for PIB-type ATPases (i.e., pbrA/cadA/zntA). A total of 10 pbrA/cadA/zntA loci exhibited evidence of acquisition by horizontal gene transfer. A remarkable dissemination of the horizontally acquired PIB-type ATPases was supported by unusual DNA base compositions and phylogenetic incongruence. Numerous Pbr PIB-type ATPase-positive FRC isolates belonging to the genus Arthrobacter tolerated toxic concentrations of soluble U(VI) (UO22+) at pH 4. These unrelated, yet synergistic, physiological traits observed in Arthrobacter isolates residing in the contaminated FRC subsurface may contribute to the survival of the organisms in such an extreme environment. This study is, to the best of our knowledge, the first study to report broad horizontal transfer of PIB-type ATPases in contaminated subsurface soils and is among the first studies to report uranium tolerance of aerobic heterotrophs obtained from the acidic subsurface at the DOE FRC. PMID:16672448

  8. Key design factors affecting microbial community composition and pathogenic organism removal in horizontal subsurface flow constructed wetlands.

    PubMed

    Morató, Jordi; Codony, Francesc; Sánchez, Olga; Pérez, Leonardo Martín; García, Joan; Mas, Jordi

    2014-05-15

    Constructed wetlands constitute an interesting option for wastewater reuse since high concentrations of contaminants and pathogenic microorganisms can be removed with these natural treatment systems. In this work, the role of key design factors which could affect microbial removal and wetland performance, such as granular media, water depth and season effect was evaluated in a pilot system consisting of eight parallel horizontal subsurface flow (HSSF) constructed wetlands treating urban wastewater from Les Franqueses del Vallès (Barcelona, Spain). Gravel biofilm as well as influent and effluent water samples of these systems were taken in order to detect the presence of bacterial indicators such as total coliforms (TC), Escherichia coli, fecal enterococci (FE), Clostridium perfringens, and other microbial groups such as Pseudomonas and Aeromonas. The overall microbial inactivation ratio ranged between 1.4 and 2.9 log-units for heterotrophic plate counts (HPC), from 1.2 to 2.2 log units for total coliforms (TC) and from 1.4 to 2.3 log units for E. coli. The presence of fine granulometry strongly influenced the removal of all the bacterial groups analyzed. This effect was significant for TC (p=0.009), E. coli (p=0.004), and FE (p=0.012). Shallow HSSF constructed wetlands were more effective for removing Clostridium spores (p=0.039), and were also more efficient for removing TC (p=0.011) and E. coli (p=0.013) when fine granulometry was used. On the other hand, changes in the total bacterial community from gravel biofilm were examined by using denaturing gradient gel electrophoresis (DGGE) and sequencing of polymerase chain reaction (PCR)-amplified fragments of the 16S rRNA gene recovered from DGGE bands. Cluster analysis of the DGGE banding pattern from the different wetlands showed that microbial assemblages separated according to water depth, and sequences of different phylogenetic groups, such as Alpha, Beta and Delta-Proteobacteria, Nitrospirae, Bacteroidetes

  9. Performance comparison and economics analysis of waste stabilization ponds and horizontal subsurface flow constructed wetlands treating domestic wastewater: a case study of the Juja sewage treatment works.

    PubMed

    Mburu, Njenga; Tebitendwa, Sylvie M; van Bruggen, Johan J A; Rousseau, Diederik P L; Lens, Piet N L

    2013-10-15

    The performance, effluent quality, land area requirement, investment and operation costs of a full-scale waste stabilization pond (WSP) and a pilot scale horizontal subsurface flow constructed wetland (HSSF-CW) at Jomo Kenyatta University of Agriculture and Technology (JKUAT) were investigated between November 2010 to January 2011. Both systems gave comparable medium to high levels of organic matter and suspended solids removal. However, the WSP showed a better removal for Total Phosphorus (TP) and Ammonium (NH4(+)-N). Based on the population equivalent calculations, the land area requirement per person equivalent of the WSP system was 3 times the area that would be required for the HSSF-CW to treat the same amount of wastewater. The total annual cost estimates consisting of capital, operation and maintenance (O&M) costs were comparable for both systems. However, the evaluation of the capital cost of either system showed that it is largely influenced by the size of the population served, local cost of land and the construction materials involved. Hence, one can select either system in terms of treatment efficiency. When land is available other factor including the volume of wastewater or the investment, and O&M costs determine the technology selection.

  10. Total nitrogen and ammonia removal prediction in horizontal subsurface flow constructed wetlands: use of artificial neural networks and development of a design equation.

    PubMed

    Akratos, Christos S; Papaspyros, John N E; Tsihrintzis, Vassilios A

    2009-01-01

    The aim of this paper is to examine if artificial neural networks (ANNs) can predict nitrogen removal in horizontal subsurface flow (HSF) constructed wetlands (CWs). ANN development was based on experimental data from five pilot-scale CW units. The proper selection of the components entering the ANN was achieved using principal component analysis (PCA), which identified the main factors affecting TN removal, i.e., porous media porosity, wastewater temperature and hydraulic residence time. Two neural networks were examined: the first included only the three factors selected from the PCA, and the second included in addition meteorological parameters (i.e., barometric pressure, rainfall, wind speed, solar radiation and humidity). The first model could predict TN removal rather satisfactorily (R(2)=0.53), and the second resulted in even better predictions (R(2)=0.69). From the application of the ANNs, a design equation was derived for TN removal prediction, resulting in predictions comparable to those of the ANNs (R(2)=0.47). For the validation of the results of the ANNs and of the design equation, available data from the literature were used and showed a rather satisfactory performance.

  11. The structure and spatio-temporal distribution of the Archaea in a horizontal subsurface flow constructed wetland.

    PubMed

    Bouali, Moez; Zrafi-Nouira, Ines; Bakhrouf, Amina; Le Paslier, Denis; Chaussonnerie, Sébastien; Ammar, Emna; Sghir, Abdelghani

    2012-10-01

    In this study, archaeal community structure and temporal dynamics were monitored, using 16S rRNA clone libraries construction from a horizontal subsurface flow constructed wetland. Phylogenetic assignation of 1026 16S rRNA gene sequences shows that 96.2% of the total operational taxonomic units (OTUs) were affiliated with Thaumarchaeota, a newly proposed archaeal phylum and 3.7% with unclassified Archaea. Among the total sequences, 42% and 40.2% were affiliated with Candidatus Nitrososphaera and unclassified Nitrosopumilus respectively with more than 99% similarity. Results suggest that several dominant and active nitrifiers may benefit from the micro-aerobic conditions around the reed roots to perform ammonia oxidation. The archaeal diversity detected in the rhizosphere zone is clearly different from that detected in the bottom basin. This engineered habitat revealed the reed root and the water composition effects on the archaeal diversity.

  12. Optimization of a catchment-scale coupled surface-subsurface hydrological model using pilot points

    NASA Astrophysics Data System (ADS)

    Danapour, Mehrdis; Stisen, Simon; Lajer Højberg, Anker

    2016-04-01

    Transient coupled surface-subsurface models are usually complex and contain a large amount of spatio-temporal information. In the traditional calibration approach, model parameters are adjusted against only few spatially aggregated observations of discharge or individual point observations of groundwater head. However, this approach doesn't enable an assessment of spatially explicit predictive model capabilities at the intermediate scale relevant for many applications. The overall objectives of this project is to develop a new model calibration and evaluation framework by combining distributed model parameterization and regularization with new types of objective functions focusing on optimizing spatial patterns rather than individual points or catchment scale features. Inclusion of detailed observed spatial patterns of hydraulic head gradients or relevant information obtained from remote sensing data in the calibration process could allow for a better representation of spatial variability of hydraulic properties. Pilot Points as an alternative to classical parameterization approaches, introduce great flexibility when calibrating heterogeneous systems without neglecting expert knowledge (Doherty, 2003). A highly parameterized optimization of complex distributed hydrological models at catchment scale is challenging due to the computational burden that comes with it. In this study the physically-based coupled surface-subsurface model MIKE SHE is calibrated for the 8,500 km2 area of central Jylland (Denmark) that is characterized by heterogeneous geology and considerable groundwater flow across topographical catchment boundaries. The calibration of the distributed conductivity fields is carried out with a pilot point-based approach, implemented using the PEST parameter estimation tool. To reduce the high number of calibration parameters, PEST's advanced singular value decomposition combined with regularization was utilized and a reduction of the model's complexity was

  13. Dairy farm wastewater treatment using horizontal subsurface flow wetlands with Typha domingensis and different substrates.

    PubMed

    Schierano, María Celeste; Maine, María Alejandra; Panigatti, María Cecilia

    2017-01-01

    The aim of this work was to evaluate the influence of different substrates in the performance of a horizontal flow constructed wetland employed in dairy farm wastewater treatment. Typha domingensis was chosen for this study due to its high productivity and efficiency in nutrient removal. Fifteen microcosm-scale reactors simulating horizontal flow constructed wetlands were disposed in a greenhouse in triplicate. Five substrates (river gravel, gravel, LECA, river gravel + zeolite and gravel + zeolite) were evaluated. Real effluent with previous treatment was used. Dairy farm effluents favoured T. domingensis growth, probably due to their high nutrient concentrations. The treatments with the different substrates studied were efficient in the treatment of the dairy farm effluent obtaining ammonium ([Formula: see text]) and total phosphorus (TP) removals between 88-99% and 86-99%, respectively. Removal efficiencies were significantly higher in treatments using LECA and combined substrate (gravel + zeolite). After treatment, the quality of the final effluent was significantly improved. Outlet effluent complied with regulations and could be discharged into the environment.

  14. Comparison of vertical and horizontal flow planted and unplanted subsurface flow wetlands treating municipal wastewater.

    PubMed

    Pandey, M K; Jenssen, P D; Krogstad, T; Jonasson, Sven

    2013-01-01

    In the search for design criteria for constructed wetlands (CWs) in Nepal a semi-scale experimental setup including horizontal flow (HF) and vertical flow (VF) CWs was developed. This paper compares the performance of HF and VF wetlands, and planted with unplanted beds. The experimental setup consists of two units of HF and VF beds of size 6 m × 2 m × 0.6 m and 6 m × 2 m × 0.8 m (length × width × depth) respectively. For both HF and VF systems, one unit was planted with Phragmites karka (local reed) and one was not planted. The systems were fed with wastewater drawn from the grit chamber of a municipal wastewater treatment plant. The media consisted of river gravel. In the first phase of the experiment the hydraulic loading rate (HLR) was varied in steps; 0.2, 0.08, 0.04 m(3)/m(2)/d and the percent removal increase with decrease in HLR for all beds and parameters except for total phosphorus. In the second phase the loading rate of 0.04 m(3)/m(2)/d was run for 7 months. In both parts of the experiment the planted beds performed better than the unplanted beds and the VF better than the HF beds. To meet Nepalese discharge standards HF beds are sufficient, but to meet stricter requirements a combination of HF and VF beds are recommended.

  15. Nitrogen removal performance in planted and unplanted horizontal subsurface flow constructed wetlands treating different influent COD/N ratios.

    PubMed

    Wang, Wei; Ding, Yi; Ullman, Jeffrey L; Ambrose, Richard F; Wang, Yuhui; Song, Xinshan; Zhao, Zhimiao

    2016-05-01

    Microcosm horizontal subsurface flow constructed wetlands (HSSFCWs) were used to examine the impacts of vegetation on nitrogen dynamics treating different influent COD/N ratios (1:1, 4:1, and 8:1). An increase in the COD/N ratio led to increased reductions in NO3 and total inorganic nitrogen (TIN) in planted and unplanted wetlands, but diminished removal of NH4. The HSSFCW planted with Canna indica L. exhibited a significant reduction in NH4 compared to the unplanted system, particularly in the active root zone where NH4 removal performance increased by up to 26 % at the COD/N ratio of 8:1. There was no significant difference in NO3 removal between the planted and unplanted wetlands. TIN removal efficiency in the planted wetland increased with COD/N ratios, which was likely influenced by plant uptake. NH4 reductions were greater in planted wetland at the 20- and 40-cm depths while NO3 reductions were uniformly greater with depth in all cases, but no statistical difference was impacted by depth on TIN removal. These findings show that planting a HSSFCW can provide some benefit in reducing nitrogen loads in effluents, but only when a sufficient carbon source is present.

  16. Pathways of nitrobenzene degradation in horizontal subsurface flow constructed wetlands: Effect of intermittent aeration and glucose addition.

    PubMed

    Kirui, Wesley K; Wu, Shubiao; Kizito, Simon; Carvalho, Pedro N; Dong, Renjie

    2016-01-15

    Intermittent aeration and addition of glucose were applied to horizontal subsurface flow constructed wetlands in order to investigate the effect on pathways of nitrobenzene (NB) degradation and interactions with microbial nitrogen and sulphur transformations. The experiment was carried out in three phases A, B and C consisting of different NB loading and glucose dosing. For each phase, the effect of aeration was assessed by intermittently aerating one wetland and leaving one unaerated. Regardless of whether or not the wetland was aerated, at an influent NB concentration of 140 mg/L, both wetlands significantly reduced NB to less than 2 mg/L, a reduction efficiency of 98%. However, once the influent NB concentration was increased to 280 mg/L, the aerated wetland had a higher removal performance 82% compared to that of the unaerated wetland 71%. Addition of glucose further intensified the NB removal to 95% in the aerated wetlands and 92% in the unaerated. Aeration of wetlands enhanced NB degradation, but also resulted in higher NB volatilization of 6 mg m(-2) d(-1). The detected high concentration of sulphide 20-60 mg/L in the unaerated wetland gave a strong indication that NB may act as an electron donor to sulphate-reducing bacteria, but this should be further investigated. Aeration positively improved NB removal in constructed wetlands, but resulted in higher NB volatilization. Glucose addition induced co-metabolism to enhance NB degradation.

  17. Modeling total phosphorus removal in an aquatic environment restoring horizontal subsurface flow constructed wetland based on artificial neural networks.

    PubMed

    Li, Wei; Zhang, Yan; Cui, Lijuan; Zhang, Manyin; Wang, Yifei

    2015-08-01

    A horizontal subsurface flow constructed wetland (HSSF-CW) was designed to improve the water quality of an artificial lake in Beijing Wildlife Rescue and Rehabilitation Center, Beijing, China. Artificial neural networks (ANNs), including multilayer perceptron (MLP) and radial basis function (RBF), were used to model the removal of total phosphorus (TP). Four variables were selected as the input parameters based on the principal component analysis: the influent TP concentration, water temperature, flow rate, and porosity. In order to improve model accuracy, alternative ANNs were developed by incorporating meteorological variables, including precipitation, air humidity, evapotranspiration, solar heat flux, and barometric pressure. A genetic algorithm and cross-validation were used to find the optimal network architectures for the ANNs. Comparison of the observed data and the model predictions indicated that, with careful variable selection, ANNs appeared to be an efficient and robust tool for predicting TP removal in the HSSF-CW. Comparison of the accuracy and efficiency of MLP and RBF for predicting TP removal showed that the RBF with additional meteorological variables produced the most accurate results, indicating a high potentiality for modeling TP removal in the HSSF-CW.

  18. Effect of diffusional mass transfer on the performance of horizontal subsurface flow constructed wetlands in tropical climate conditions.

    PubMed

    Njau, K N; Gastory, L; Eshton, B; Katima, J H Y; Minja, R J A; Kimwaga, R; Shaaban, M

    2011-01-01

    The effect of mass transfer on the removal rate constants of BOD5, NH3, NO3 and TKN has been investigated in a Horizontal Subsurface Flow Constructed Wetland (HSSFCW) planted with Phragmites mauritianus. The plug flow model was assumed and the inlet and outlet concentrations were used to determine the observed removal rate constants. Mass transfer effects were studied by assessing the influence of interstitial velocity on pollutant removal rates in CW cells of different widths. The flow velocities varied between 3-46 m/d. Results indicate that the observed removal rate constants are highly influenced by the flow velocity. Correlation of dimensionless groups namely Reynolds Number (Re), Sherwood Number (Sh) and Schmidt Number (Sc) were applied and log-log plots of rate constants against velocity yielded straight lines with values beta = 0.87 for BOD5, 1.88 for NH3, 1.20 for NO3 and 0.94 for TKN. The correlation matched the expected for packed beds although the constant beta was higher than expected for low Reynolds numbers. These results indicate that the design values of rate constants used to size wetlands are influenced by flow velocity. This paper suggests the incorporation of mass transfer into CW design procedures in order to improve the performance of CW systems and reduce land requirements.

  19. Design configurations affecting flow pattern and solids accumulation in horizontal free water and subsurface flow constructed wetlands.

    PubMed

    Pedescoll, A; Sidrach-Cardona, R; Sánchez, J C; Carretero, J; Garfi, M; Bécares, E

    2013-03-01

    The aim of this study was to evaluate the effect of different horizontal constructed wetland (CW) design parameters on solids distribution, loss of hydraulic conductivity over time and hydraulic behaviour, in order to assess clogging processes in wetlands. For this purpose, an experimental plant with eight CWs was built at mesocosm scale. Each CW presented a different design characteristic, and the most common CW configurations were all represented: free water surface flow (FWS) with different effluent pipe locations, FWS with floating macrophytes and subsurface flow (SSF), and the presence of plants and specific species (Typha angustifolia and Phragmites australis) was also considered. The loss of the hydraulic conductivity of gravel was greatly influenced by the presence of plants and organic load (representing a loss of 20% and c.a. 10% in planted wetlands and an overloaded system, respectively). Cattail seems to have a greater effect on the development of clogging since its below-ground biomass weighed twice as much as that of common reed. Hydraulic behaviour was greatly influenced by the presence of a gravel matrix and the outlet pipe position. In strict SSF CW, the water was forced to cross the gravel and tended to flow diagonally from the top inlet to the bottom outlet (where the inlet and outlet pipes were located). However, when FWS was considered, water preferentially flowed above the gravel, thus losing half the effective volume of the system. Only the presence of plants seemed to help the water flow partially within the gravel matrix.

  20. Emerging organic contaminant removal depending on primary treatment and operational strategy in horizontal subsurface flow constructed wetlands: influence of redox.

    PubMed

    Avila, Cristina; Reyes, Carolina; Bayona, Josep María; García, Joan

    2013-01-01

    This study aimed at assessing the influence of primary treatment (hydrolytic upflow sludge blanket (HUSB) reactor vs. conventional settling) and operational strategy (alternation of saturated/unsaturated phases vs. permanently saturated) on the removal of various emerging organic contaminants (i.e. ibuprofen, diclofenac, acetaminophen, tonalide, oxybenzone, bisphenol A) in horizontal subsurface flow constructed wetlands. For that purpose, a continuous injection experiment was carried out in an experimental treatment plant for 26 days. The plant had 3 treatment lines: a control line (settler-wetland permanently saturated), a batch line (settler-wetland operated with saturate/unsaturated phases) and an anaerobic line (HUSB reactor-wetland permanently saturated). In each line, wetlands had a surface area of 2.95 m(2), a water depth of 25 cm and a granular medium D(60) = 7.3 mm, and were planted with common reed. During the study period the wetlands were operated at a hydraulic and organic load of 25 mm/d and about 4.7 g BOD/m(2)d, respectively. The injection experiment delivered very robust results that show how the occurrence of higher redox potentials within the wetland bed promotes the elimination of conventional quality parameters as well as emerging microcontaminants. Overall, removal efficiencies were always greater for the batch line than for the control and anaerobic lines, and to this respect statistically significantly differences were found for ibuprofen, diclofenac, oxybenzone and bisphenol A. As an example, ibuprofen, whose major removal mechanism has been reported to be biodegradation under aerobic conditions, showed a higher removal in the batch line (85%) than in the control (63%) and anaerobic (52%) lines. Bisphenol A showed also a great dependence on the redox status of the wetlands, finding an 89% removal rate for the batch line, as opposed to the control and anaerobic lines (79 and 65%, respectively). Furthermore, diclofenac showed a greater

  1. Evaluation of the giant reed (Arundo donax) in horizontal subsurface flow wetlands for the treatment of dairy processing factory wastewater.

    PubMed

    Idris, Shaharah Mohd; Jones, Paul L; Salzman, Scott A; Croatto, George; Allinson, Graeme

    2012-09-01

    Two emergent macrophytes, Arundo donax and Phragmites australis, were established in experimental horizontal subsurface flow (HSSF), gravel-based constructed wetlands (CWs) and challenged by treated dairy processing factory wastewater with a median electrical conductivity of 8.9 mS cm(-1). The hydraulic loading rate was tested at 3.75 cm day(-1). In general, the plants grew well during the 7-month study period, with no obvious signs of salt stress. The major water quality parameters monitored (biological oxygen demand (BOD), suspended solids (SS) and total nitrogen (TN) but not total phosphorus) were generally improved after the effluent had passed through the CWs. There was no significance different in removal efficiencies between the planted beds and unplanted gravel beds (p > 0.007), nor was there any significant difference in removal efficiencies between the A. donax and P. australis beds for most parameters. BOD, SS and TN removal in the A. donax and P. australis CWs was 69, 95 and 26 % and 62, 97 and 26 %, respectively. Bacterial removal was observed but only to levels that would allow reuse of the effluent for use on non-food crops under Victorian state regulations. As expected, the A. donax CWs produced considerably more biomass (37 ± 7.2 kg wet weight) than the P. australis CWs (11 ± 1.4 kg wet weight). This standing crop equates to approximately 179 and 68 tonnes ha(-1) year(-1) biomass (dry weight) for A. donax and P. australis, respectively (assuming a 250-day growing season and single-cut harvest). The performance similarity of the A. donax and P. australis planted CWs indicates that either may be used in HSSF wetlands treating dairy factory wastewater, although the planting of A. donax provides additional opportunities for secondary income streams through utilisation of the biomass produced.

  2. Bacterial community analysis by PCR-DGGE and 454-pyrosequencing of horizontal subsurface flow constructed wetlands with front aeration.

    PubMed

    Zhong, Fei; Wu, Juan; Dai, Yanran; Yang, Lihua; Zhang, Zhaohui; Cheng, Shuiping; Zhang, Qiong

    2015-02-01

    Horizontal subsurface flow constructed wetlands (HSSF CWs) with and without redox manipulation by front aeration were operated to treat mechanically pretreated wastewater from a nearby wastewater treatment plant. Polymerase chain reaction-denaturing gradient gel electrophoresis and 454-pyrosequencing were used to characterize the shifts in bacterial community diversity and composition in response to front aeration in the HSSF CWs. Both techniques revealed similar bacterial diversity between the HSSF CWs with (ACW) and without front aeration (NACW). Differences in microbial functional groups between the ACW and the NACW substrate samples were identified with 454-pyrosequencing. Nitrite-oxidizing bacteria (Nitrospira) and ammonia-oxidizing bacteria (Nitrosomonas) had much higher abundances in the ACW, whereas more sequences related to sulfate-reducing bacteria and anaerobic sulfur-oxidizing bacteria (genera Sulfuricella, Sulfuritalea, and Sulfuricurvum) were detected in the NACW. Removal efficiencies for NH₄(+)-N, PO₄(3-)-P and chemical oxygen demand in the ACW were 48.7 ± 15.5, 70.2 ± 13.5, and 82.0 ± 6.4%, respectively, whereas the removal efficiencies for these parameters in the NACW were 10.3 ± 14.0, 53.1 ± 18.9, and 68.8 ± 10.7%, respectively. In the ACW, the stimulation of nitrification via front aeration supplied more NO₂(-)-N and NO₃(-)-N to the subsequent denitrification process than in the NACW, resulting in higher total inorganic nitrogen removal efficiency. The differences in treatment efficiencies between the ACW and the NACW could be partially explained by the different bacterial community compositions in the two CWs.

  3. [Removal efficiency of C and N in micro-polluted river through a subsurface-horizontal flow constructed wetlands].

    PubMed

    Yang, Xin-ping; Zhou, Li-xiang; Dai, Yuan-yuan; Cui, Chun-hong

    2008-08-01

    A subsurface-horizontal flow constructed wetlands (CWs) planted with reed was used to treat micro-polluted river water in this study with an aim to investigate the long-term treatment efficiency of CWs especially for organic C and N. Average data obtained from two-year plant growth season showed that performance of the wetlands appeared to be affected by both establishment/maturation factors and year-to-year climatic variations. The results displayed that the removal of C and N in the influent depended, to a certain extend, on plant growth and seasonal variations, especially for total N removal. It was observed that C removal occurred mainly in the front of CWs in the first-year's operation period and then was translocated to the rear end of wetlands in the second-year's operation period. C/N ratio in the influent was 5 or more, indicating enough C source supply for denitrification. Organic C removal efficiencies varied from 6.10% to 37.83% throughout the trial. Average total N removal efficiency of 15.51% in the first-year operation period and then declined to 8.61% in the second year. The highest removal efficiency of total N was below 40% throughout the two-year trial. It was found that nitrification and denitrification reached dynamic equilibrium at the middle of the wetlands where the highest total N removal efficiency occurred. The greatest oxygen consumption was observed in the front and middle of CWs. It was noted that nitrification occurred even in deep layer located in the rear end of the wetlands in the second-year operation period. Nitrification and denitrification occurred concurrently with C and total N removal along the stream way. Low-molecular-weight organic acids released from reed rhizosphere seemed to have a significant inhibitory effect on chemoautrophic nitrifying bacteria, which involved in nitrogen removal efficiency of the wetlands, particularly during spring and autumn.

  4. Impact of different feeding strategies and plant presence on the performance of shallow horizontal subsurface-flow constructed wetlands.

    PubMed

    Caselles-Osorio, Aracelly; García, Joan

    2007-06-01

    The aim of this investigation was to evaluate the effect of continuous and intermittent feeding strategies on contaminant removal efficiency of shallow horizontal subsurface-flow constructed wetlands (SSF CWs). Also it was tested the effect of the presence of plant aboveground biomass on removal efficiency. Two experimental wetlands planted with common reed were subjected to a three-phase, 10-month experiment involving a common source of settled urban wastewater with a hydraulic loading rate of 26 mm/d during the first and second phases and 39 mm/d during the third. In the first and second phases one of the wetlands was fed continuously while the other was fed intermittently. In the third phase both systems were operated intermittently, but in one the macrophyte aboveground biomass was cut in order to study the effect of plant aboveground biomass on the removal efficiency. The intermittently fed system presented systematically more oxidised environmental conditions and higher ammonium removal efficiencies (on average 80 and 99% for the first and the second phases respectively) compared with the continuously fed system (71 and 85%). The mass amount of ammonium removed ranged from 0.58 to 0.67 g N/m2 d for the intermittently fed system and from 0.52 to 0.58 g N/m2 d for the continuously fed system. Sulphate removal was higher in the continuously fed system (on average 76 and 79% for the first and second phases respectively) compared with the intermittently fed system (51 and 58%). In the third phase the wetland that operated with aboveground biomass exhibited more oxidised environmental conditions and better removal efficiencies (on average 81% for COD and 98% for ammonium) than the wetland operated without aboveground biomass (73% for COD and 72% for ammonium). The results of this study indicate that the intermittent feeding strategy improved the removal of ammonium and the presence of aboveground biomass enhanced the removal of COD and ammonium.

  5. Removal of organics in constructed wetlands with horizontal sub-surface flow: a review of the field experience.

    PubMed

    Vymazal, Jan; Kröpfelová, Lenka

    2009-06-15

    Constructed wetlands with horizontal sub-surface flow (HF CWs) have successfully been used for treatment various types of wastewater for more than four decades. Most systems have been designed to treat municipal sewage but the use for wastewaters from agriculture, industry and landfill leachate in HF CWs is getting more attention nowadays. The paper summarizes the results from more than 400 HF CWs from 36 countries around the world. The survey revealed that the highest removal efficiencies for BOD(5) and COD were achieved in systems treating municipal wastewater while the lowest efficiency was recorded for landfill leachate. The survey also revealed that HF CWs are successfully used for both secondary and tertiary treatment. The highest average inflow concentrations of BOD(5) (652 mg l(-1)) and COD (1865 mg l(-1)) were recorded for industrial wastewaters followed by wastewaters from agriculture for BOD(5) (464 mg l(-1)) and landfill leachate for COD (933 mg l(-1)). Hydraulic loading data reveal that the highest loaded systems are those treating wastewaters from agriculture and tertiary municipal wastewaters (average hydraulic loading rate 24.3 cm d(-1)). On the other hand, landfill leachate systems in the survey were loaded with average only 2.7 cm d(-1). For both BOD(5) and COD, the highest average loadings were recorded for agricultural wastewaters (541 and 1239 kg ha(-1) d(-1), respectively) followed by industrial wastewaters (365 and 1212 kg ha(-1) d(-1), respectively). The regression equations for BOD(5) and COD inflow/outflow concentrations yielded very loose relationships. Much stronger relationships were found for inflow/outflow loadings and especially for COD. The influence of vegetation on removal of organics in HF CWs is not unanimously agreed but most studies indicated the positive effect of macrophytes.

  6. Effects of interspecific competition on the growth of macrophytes and nutrient removal in constructed wetlands: A comparative assessment of free water surface and horizontal subsurface flow systems.

    PubMed

    Zheng, Yucong; Wang, Xiaochang; Dzakpasu, Mawuli; Zhao, Yaqian; Ngo, Huu Hao; Guo, Wenshan; Ge, Yuan; Xiong, Jiaqing

    2016-05-01

    The outcome of competition between adjoining interspecific colonies of Phragmites and Typha in two large field pilot-scale free water surface (FWS) and subsurface flow (SSF) CWs is evaluated. According to findings, the effect of interspecific competition was notable for Phragmites australis, whereby it showed the highest growth performance in both FWS and SSF wetland. In a mixed-culture, P. australis demonstrates superiority in terms of competitive interactions for space between plants. Furthermore, the interspecific competition among planted species seemed to cause different ecological responses of plant species in the two CWs. For example, while relatively high density and shoot height determined the high aboveground dry weight of P. australis in the FWS wetland, this association was not evident in the SSF. Additionally, while plants nutrients uptake accounts for a higher proportion of the nitrogen removal in FWS, that in the SSF accounts for a higher proportion of the phosphorous removal.

  7. Horizontal gene transfer as adaptive response to heavy metal stress in subsurface microbial communities. Final report for period October 15, 1997 - October 15, 2000

    SciTech Connect

    Smets, B. F.

    2001-12-21

    Horizontal gene transfer as adaptive response to heavy metal stress in the presence of heavy metal stress was evaluated in oligotrophic subsurface soil laboratory scale microcosms. Increasing levels of cadmium (10, 100 and 1000 mM) were applied and an E. coli donor was used to deliver the target plasmids, pMOL187 and pMOL222, which contained the czc and ncc operons, and the helper plasmid RP4. Plasmid transfer was evaluated through monitoring of the heavy metal resistance and presence of the genes. The interactive, clearly revealed, effect of biological and chemical external factors on the extent of plasmid-DNA propagation in microbial communities in contaminated soil environments was observed in this study. Additionally, P.putida LBJ 415 carrying a suicide construct was used to evaluate selective elimination of a plasmid donor.

  8. The effect of primary treatment and flow regime on clogging development in horizontal subsurface flow constructed wetlands: An experimental evaluation.

    PubMed

    Pedescoll, Anna; Corzo, Angélica; Alvarez, Eduardo; García, Joan; Puigagut, Jaume

    2011-06-01

    The effect of both the type of primary treatment (hydrolitic up-flow sludge blanket (HUSB) reactor and conventional settling) and the flow regime (batch and continuous) on clogging development in subsurface flow constructed wetlands (SSF CWs) was studied. Clogging indicators (such as accumulated solids, hydraulic conductivity and drainable porosity) were determined in an experimental plant with three treatment lines. Correlations were encountered between the solids accumulated and both saturated hydraulic conductivity and drainable porosity reduction over time (74.5% and 89.2% of correlation, respectively). SSF CW implemented with a HUSB reactor accumulated ca. 30% lower sludge (1.9 kg DM/m(2)) than a system with a settler (2.5-2.8 kg DM/m(2)). However, no significant differences were recorded among treatment lines concerning hydraulic parameters (such as hydraulic conductivity or porosity). Root system development contributed to clogging. Accordingly, planted wetlands showed between 30% and 40% and 10% lower hydraulic conductivity and porosity reduction, respectively, than non-planted wetlands.

  9. A pilot study of a subsurface-flow constructed wetland treating membrane concentrate produced from reclaimed water.

    PubMed

    Chakraborti, Rajat K; Bays, James S; Ng, Thien; Balderrama, Lou; Kirsch, Terry

    2015-01-01

    A pilot study was conducted for 7 months for the City of Oxnard, California, on the use of constructed wetlands to treat concentrate produced by microfiltration and reverse osmosis (RO) of reclaimed wastewater. The treatment performance of a transportable subsurface-flow wetland was investigated by monitoring various forms of nitrogen, orthophosphate, oxygen demand, organic carbon, and selenium. Significant mass removal of constituents was measured under two hydraulic residence times (HRTs) (2.5 and 5 days). Inflow and outflow concentrations of nitrate-N and ammonia-N were significantly different for both HRTs, whereas nitrite-N and total organic carbon (TOC) were significantly different during HRT2. Mass removal by the constructed wetland averaged 61% of nitrate-N, 32% of nitrite-N, 42% of ammonia-N, 43% of biochemical oxygen demand, 19% of orthophosphate as P, 18% of TOC and 61% of selenium. Mass removal exceeded concentration reductions through water volume loss through evapotranspiration. Calibrated first-order area-based removal rates were consistent with literature ranges, and were greater during HRT1 consistent with greater mass loads, higher hydraulic loading and shorter HRTs. The rate constants may provide a basis for sizing a full-scale wetland receiving a similar quality of water. The results indicated that engineered wetlands can be useful in the management of RO membrane concentrate for reclaimed water reuse.

  10. Dynamics of sulphur compounds in horizontal sub-surface flow laboratory-scale constructed wetlands treating artificial sewage.

    PubMed

    Wiessner, A; Rahman, K Z; Kuschk, P; Kästner, M; Jechorek, M

    2010-12-01

    The knowledge regarding the dynamics of sulphur compounds inside constructed wetlands is still insufficient. Experiments in planted (Juncus effusus) and unplanted horizontal sub-surface-flow laboratory-scale constructed wetlands fed with artificial wastewater were carried out to evaluate the sulphate reduction, the composition and dynamics of generated sulphur compounds, as well as the influence of carbon load and plants on processes of sulphur transformation. In planted and unplanted wetlands, the addition of organic carbon (TOC of about 120 mg L(-1)) immediately affected the transformation of up to 90% of the incoming sulphate (150 mg L(-1)), directing it mainly towards elemental sulphur (30%) and sulphide (8%). During this experimental period, nearly 52% of the transformed sulphate-sulphur was calculated to be immobilized inside the planted wetland and 66% inside the unplanted one. In subsequent experiments, the deficiency of organic carbon inside the planted wetlands favoured the decrease of elemental sulphur in the pore water coupled to retransformation of depot-sulphur to dissolved sulphate. Nearly 90% of the deposited and reduced sulphur was found to be reoxidized. In principle, the results indicate a substantial improvement of this reoxidation of sulphur by oxygen released by the helophytes. Surplus of organic carbon promotes the ongoing sulphate reduction and the stability of deposed and dissolved reduced sulphur compounds. In contrast, inside the unplanted control wetland, a relative stability of the formed sulphur depots and the generated amount of dissolved sulphur compounds including elemental sulphur could be observed independently of the different loading conditions.

  11. Field evaluation of a horizontal well recirculation system for groundwater treatment: Pilot test at the Clean Test Site Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    Muck, M.T.; Kearl, P.M.; Siegrist, R.L.

    1998-08-01

    This report presents the results of field testing a horizontal well recirculation system at the Portsmouth Gaseous Diffusion Plant (PORTS). The recirculation system uses a pair of horizontal wells, one for groundwater extraction and treatment and the other for reinjection of treated groundwater, to set up a recirculation flow field. The induced flow field from the injection well to the extraction well establishes a sweeping action for the removal and treatment of groundwater contaminants. The overall purpose of this project is to study treatment of mixed groundwater contaminants that occur in a thin water-bearing zone not easily targeted by traditional vertical wells. The project involves several research elements, including treatment-process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and pilot testing at a contaminated site. The results of the pilot test at an uncontaminated site, the Clean Test Site (CTS), are presented in this report.

  12. High-throughput pyrosequencing analysis of bacteria relevant to cometabolic and metabolic degradation of ibuprofen in horizontal subsurface flow constructed wetlands.

    PubMed

    Li, Yifei; Wu, Bing; Zhu, Guibing; Liu, Yu; Ng, Wun Jern; Appan, Adhityan; Tan, Soon Keat

    2016-08-15

    The potential toxicity of pharmaceutical residues including ibuprofen on the aquatic vertebrates and invertebrates has attracted growing attention to the pharmaceutical pollution control using constructed wetlands, but there lacks of an insight into the relevant microbial degradation mechanisms. This study investigated the bacteria associated with the cometabolic and metabolic degradation of ibuprofen in a horizontal subsurface flow constructed wetland system by high-throughput pyrosequencing analysis. The ibuprofen degradation dynamics, bacterial diversity and evenness, and bacterial community structure in a planted bed with Typha angustifolia and an unplanted bed (control) were compared. The results showed that the plants promoted the microbial degradation of ibuprofen, especially at the downstream zones of wetland. However, at the upstream one-third zone of wetland, the presence of plants did not significantly enhance ibuprofen degradation, probably due to the much greater contribution of cometabolic behaviors of certain non-ibuprofen-degrading microorganisms than that of the plants. By analyzing bacterial characteristics, we found that: (1) The aerobic species of family Flavobacteriaceae, family Methylococcaceae and genus Methylocystis, and the anaerobic species of family Spirochaetaceae and genus Clostridium_sensu_stricto were the most possible bacteria relevant to the cometabolic degradation of ibuprofen; (2) The family Rhodocyclaceae and the genus Ignavibacterium closely related to the plants appeared to be associated with the metabolic degradation of ibuprofen.

  13. Analysis of conservative tracer measurement results using the Frechet distribution at planted horizontal subsurface flow constructed wetlands filled with coarse gravel and showing the effect of clogging processes.

    PubMed

    Dittrich, Ernő; Klincsik, Mihály

    2015-11-01

    A mathematical process, developed in Maple environment, has been successful in decreasing the error of measurement results and in the precise calculation of the moments of corrected tracer functions. It was proved that with this process, the measured tracer results of horizontal subsurface flow constructed wetlands filled with coarse gravel (HSFCW-C) can be fitted more accurately than with the conventionally used distribution functions (Gaussian, Lognormal, Fick (Inverse Gaussian) and Gamma). This statement is true only for the planted HSFCW-Cs. The analysis of unplanted HSFCW-Cs needs more research. The result of the analysis shows that the conventional solutions (completely stirred series tank reactor (CSTR) model and convection-dispersion transport (CDT) model) cannot describe these types of transport processes with sufficient accuracy. These outcomes can help in developing better process descriptions of very difficult transport processes in HSFCW-Cs. Furthermore, a new mathematical process can be developed for the calculation of real hydraulic residence time (HRT) and dispersion coefficient values. The presented method can be generalized to other kinds of hydraulic environments.

  14. Nitrogen removal and its relationship with the nitrogen-cycle genes and microorganisms in the horizontal subsurface flow constructed wetlands with different design parameters.

    PubMed

    Chen, Jun; Ying, Guang-Guo; Liu, You-Sheng; Wei, Xiao-Dong; Liu, Shuang-Shuang; He, Liang-Ying; Yang, Yong-Qiang; Chen, Fan-Rong

    2017-04-10

    This study aims to investigate nitrogen removal and its relationship with the nitrogen-cycle genes and microorganisms in the horizontal subsurface flow constructed wetlands (CWs) with different design parameters. Twelve mesocosm-scale CWs with four substrates and three hydraulic loading rates were set up in the outdoor. The result showed the CWs with zeolite as substrate and HLR of 20 cm/d were selected as the best choice for the TN and NH3-N removal. It was found that the single-stage mesocosm-scale CWs were incapable to achieve high removals of TN and NH3-N due to inefficient nitrification process in the systems. This was demonstrated by the lower abundance of the nitrification genes (AOA and AOB) than the denitrification genes (nirK and nirS), and the less diverse nitrification microorganisms than the denitrification microorganisms in the CWs. The results also show that microorganism community structure including nitrogen-cycle microorganisms in the constructed wetland systems was affected by the design parameters especially the substrate type. These findings show that nitrification is a limiting factor for the nitrogen removal by CWs.

  15. Effects of Inboard Horizontal Field of View Display Limitations on Pilot Path Control During Total In-Flight Simulator (TIFS) Flight Test

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Parrish, Russell V.; Williams, Steven P.; Lavell, Jeffrey S.

    1999-01-01

    A flight test was conducted aboard Calspan's Total In-Flight Simulator (TIFS) aircraft by researchers within the External Visibility System (XVS) element of the High-Speed Research program. The purpose was to investigate the effects of inboard horizontal field of view (FOV) display limitations on pilot path control and to learn about the TIFS capabilities and limitations for possible use in future XVS flight tests. The TIFS cockpit windows were masked to represent the front XVS display area and the High-Speed Civil Transport side windows, as viewed by the pilot. Masking limited the forward FOV to 40 deg. horizontal and 50 deg. vertical for the basic flight condition, With an increase of 10 deg. horizontal in the inboard direction for the increased FOV flight condition. Two right-hand approach tasks (base-downwind-final) with a left crosswind on final were performed by three pilots using visual flight rules at Niagara Falls Airport. Each of the two tasks had three replicates for both horizontal FOV conditions, resulting in twelve approaches per test subject. Limited objective data showed that an increase of inboard FOV had no effect (deficiences in objective data measurement capabilities were noted). However, subjective results showed that a 50 deg. FOV was preferred over the 40 deg. FOV.

  16. Analysis of the metabolic utilization of carbon sources and potential functional diversity of the bacterial community in lab-scale horizontal subsurface-flow constructed wetlands.

    PubMed

    Deng, Huanhuan; Ge, Liyun; Xu, Tan; Zhang, Minghua; Wang, Xuedong; Zhang, Yalei; Peng, Hong

    2011-01-01

    Microorganisms are an integral part of the biogeochemical processes in wetlands. To improve the performance of constructed wetlands, it is very important to know the metabolic properties and functional diversity of the microbial communities. The purpose of this study is to analyze the metabolic properties and functional diversity of the microbial community in a horizontal subsurface-flow constructed wetland (CW) in a laboratory study through the sole-carbon-source utilization profiles using Biolog-ECO microplates. The technique has advantages over traditional cell culture techniques, such as molecular-level techniques-RNA amplification, which are time-consuming, expensive, and only applicable to the small number of species that may be cultured. This CW was designed to treat rural eutrophic water in China, using the plant L. This study showed that the metabolic activities of upper front substrate microorganisms (UF) were greater than those of the lower back substrate microorganisms (LB) in the CW. Integrated areas under average well color development (AWCD) curves of substrate microorganisms in the UF were 131.9, 4.8, and 99.3% higher than in the lower front part (LF), the upper back part (UB), and the LB part of the CW, respectively. Principal components analysis showed significant differences in both community structure and metabolic utilization of carbon sources between substrate microorganisms from different sampling sites. Carbon source utilization of polymers, carbohydrates, carboxylic acids, and amino acids was higher in UF than in LF, but that of amines and phenolic compounds was very similar in UF and LF. The richness, evenness, and diversity of upper substrate microbial communities were significantly higher than those of lower substrate. The LF substrate microbial communities had lower evenness than the other sampling plots, and the lowest richness of substrate microbial community was found in the LB part of the CW.

  17. A study on the effects of different hydraulic loading rates (HLR) on pollutant removal efficiency of subsurface horizontal-flow constructed wetlands used for treatment of domestic wastewaters.

    PubMed

    Çakir, Recep; Gidirislioglu, Ali; Çebi, Ulviye

    2015-12-01

    The research into the treatment of domestic wastewaters originating from Büyükdöllük village in Edirne Province was carried out over a 3 year experimental period. The wastewaters of the settlement were treated using a constructed wetland with subsurface horizontal flow, and the effects of different hydraulic loading levels on removal efficiency were studied. In order to achieve this goal, three equal chambers (ponds) of 300 m(2) each were constructed and planted with Phragmites australis. Each of the chambers was loaded with domestic wastewater with average flow discharge creating hydraulic loading rates of 0. m(3) day(-1) m(-2); 0.075 m(3) day(-1) m(-2) and 0.125 m(3) day(-1) m(-2), respectively. According to the results of the study, the inlet levels of the pollutant parameters with carbon origin in the water samples taken from the system entrance are high and the average values for three years are respectively: Biological Oxygen Demand, BOD5 -324.5 mg L(-1); Chemical Oxygen Demand, COD -484,0 mg L(-1); suspended solids (TSS) -147.3 mg L(-1) and Oil and Grease -0.123 mg L(-1). It was also determined that the removal rates of the system were closely dependent on the applied hydraulic loading levels and the highest removal rates of 64.9%, 62.5%, 86.3% and 80.34% for BOD5, COD, TSS and Oil and Grease, respectively, were determined in the pond with a hydraulic loading rate of 0.050 m(3) day(-1) m(-2). Lower removal of 57.9%, 55.5%, 81.4% and 74.5% for BOD5, COD, TSS and Oil and Grease were recorded in the pond with a hydraulic loading rate of 0.075 m(3) day(-1) m(-2); and these values were 49.1%, 47.8%, 70.9% and 62.1% for the pond with a hydraulic loading rate of 0.125 m(3) day(-1) m(-2). High removal rates were also recorded for the other investigated pollution parameters.

  18. The Effectiveness of Organic Pollutants Removal in Constructed Wetland with Horizontal Sub-Surface Flow / Efektywność Usuwania Zanieczyszczeń Organicznych W Oczyszczalni Hydrofitowej

    NASA Astrophysics Data System (ADS)

    Jakubaszek, Anita; Sadecka, Zofia

    2015-03-01

    This paper presents the results of the research work related to the removal efficiency from wastewater organic pollutants and suspended solids at HSSF (horizontal subsurface flow) constructed wetland. The average effectiveness defined as loss of value COD in wastewater has reached 77%, for BOD5 - 80% and TOC - 82%. The effect of seasonal temperature changes and the period of plant vegetation and rest on the effectiveness of wastewater treatment were also analyzed. The results of the presented research showed a decrease in the efficiency of removing organic pollutants from wastewater and suspended solids in the autumn and winter. During the vegetation the object in Małyszyn has been characterized by the effectiveness of wastewater treatment at the level of 78% for COD, 82% for BOD5, and in the non-vegetation period the effectiveness has decreased up to 75% for COD and 74% for BOD5. During the plants growth the total suspension was removed in 88%, whereas during the plants rest efficiency of removing lowered to 69%. W pracy przedstawiono wyniki badań dotyczące efektywności usuwania ze ścieków zanieczyszczeń organicznych w oczyszczalni hydrofitowej. Średnia skuteczność oczyszczania wyrażona jako obniżenie wartości ChZT w ściekach była na poziomie 77%, dla BZT5 80%, a dla OWO 82%. Analizowano również wpływ sezonowych zmian temperatury oraz okresu wegetacji i spoczynku roślin na skuteczność oczyszczania ścieków. Wyniki badań wykazały obniżenie efektywności usuwania zanieczyszczeń organicznych ze ścieków wyrażonych przez ChZT i BZT5 oraz zawiesiny ogólnej w okresie jesienno-zimowym. W okresie wegetacyjnym obiekt w Małyszynie charakteryzował się efektywnością oczyszczania ścieków na poziomie: 78% dla ChZT, 82% dla BZT5, a w sezonie pozawegetacyjnym skuteczność uległa obniżeniu do 75% w przypadku ChZT oraz 74% dla BZT5. Zawiesina ogólna w okresie wegetacji trzciny usuwana była w 88%, a w okresie powegetacyjnym w 69%.

  19. How effectively do horizontal and vertical response strategies of long-finned pilot whales reduce sound exposure from naval sonar?

    PubMed

    Wensveen, Paul J; von Benda-Beckmann, Alexander M; Ainslie, Michael A; Lam, Frans-Peter A; Kvadsheim, Petter H; Tyack, Peter L; Miller, Patrick J O

    2015-05-01

    The behaviour of a marine mammal near a noise source can modulate the sound exposure it receives. We demonstrate that two long-finned pilot whales both surfaced in synchrony with consecutive arrivals of multiple sonar pulses. We then assess the effect of surfacing and other behavioural response strategies on the received cumulative sound exposure levels and maximum sound pressure levels (SPLs) by modelling realistic spatiotemporal interactions of a pilot whale with an approaching source. Under the propagation conditions of our model, some response strategies observed in the wild were effective in reducing received levels (e.g. movement perpendicular to the source's line of approach), but others were not (e.g. switching from deep to shallow diving; synchronous surfacing after maximum SPLs). Our study exemplifies how simulations of source-whale interactions guided by detailed observational data can improve our understanding about motivations behind behaviour responses observed in the wild (e.g., reducing sound exposure, prey movement).

  20. Modeling organic matter and nitrogen removal from domestic wastewater in a pilot-scale vertical subsurface flow constructed wetland.

    PubMed

    Bustillo-Lecompte, Ciro Fernando; Mehrvar, Mehrab; Quiñones-Bolaños, Edgar; Castro-Faccetti, Claudia Fernanda

    2016-01-01

    Constructed wetlands have become an attractive alternative for wastewater treatment. However, there is not a globally accepted mathematical model to predict their performance. In this study, the VS2DTI software was used to predict the effluent biochemical oxygen demand (BOD) and total nitrogen (TN) in a pilot-scale vertical flow constructed wetland (VFCW) treating domestic wastewater. After a 5-week adaptation period, the pilot system was monitored for another 6 weeks. Experiments were conducted at hydraulic retention times (HRTs) in the range of 2-4 days with Typha latifolia as the vegetation. The raw wastewater concentrations ranged between 144-430 and 122-283 mg L(-1) for BOD5 and TN, respectively. A first-order kinetic model coupled with the advection/dispersion and Richards' equations was proposed to predict the removal rates of BOD5 and TN from domestic wastewater. Two main physical processes were modeled in this study, porous material water flow and solute transport through the different layers of the VFCW to simulate the constructed wetland (CW) conditions. The model was calibrated based on the BOD5 and TN degradation constants. The model indicated that most of BOD and TN (88 and 92%, respectively) were removed through biological activity followed by adsorption. It was also observed that the evapotranspiration was seen to have a smaller impact. An additional data series of effluent BOD and TN was used for model validation. The residual analysis of the calibrated model showed a relatively random pattern, indicating a decent fit. Thus, the VS2DTI was found to be a useful tool for CW simulation.

  1. Distribution and mass balance of hexavalent and trivalent chromium in a subsurface, horizontal flow (SF-h) constructed wetland operating as post-treatment of textile wastewater for water reuse.

    PubMed

    Fibbi, Donatella; Doumett, Saer; Lepri, Luciano; Checchini, Leonardo; Gonnelli, Cristina; Coppini, Ester; Del Bubba, Massimo

    2012-01-15

    In this study, during a two-year period, we investigated the fate of hexavalent and trivalent chromium in a full-scale subsurface horizontal flow constructed wetland planted with Phragmites australis. The reed bed operated as post-treatment of the effluent wastewater from an activated sludge plant serving the textile industrial district and the city of Prato (Italy). Chromium speciation was performed in influent and effluent wastewater and in water-suspended solids, at different depths and distances from the inlet; plants were also analyzed for total chromium along the same longitudinal profile. Removals of hexavalent and trivalent chromium equal to 72% and 26%, respectively were achieved. The mean hexavalent chromium outlet concentration was 1.6 ± 0.9 μg l(-1) and complied with the Italian legal limits for water reuse. Chromium in water-suspended solids was in the trivalent form, thus indicating that its removal from wastewater was obtained by the reduction of hexavalent chromium to the trivalent form, followed by accumulation of the latter inside the reed bed. Chromium in water-suspended solids was significantly affected by the distance from the inlet. Chromium concentrations in the different plant organs followed the same trend of suspended solids along the longitudinal profile and were much lower than those found in the solid material, evidencing a low metal accumulation in P. australis.

  2. Subsurface sounders

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Airborne or spaceborne electromagnetic systems used to detect subsurface features are discussed. Data are given as a function of resistivity of ground material, magnetic permeability of free space, and angular frequency. It was noted that resistivities vary with the water content and temperature.

  3. Effect of Whole Body Vibration Exercise in the Horizontal Direction on Balance and Fear of Falling in Elderly People: A Pilot Study

    PubMed Central

    Shim, ChungSin; Lee, YunBok; Lee, DongGeon; Jeong, BeomHo; Kim, JinBeom; Choi, YoungWoo; Lee, GyuChang; Park, Dong-sik

    2014-01-01

    [Purpose] The purpose of the present study was to investigate the effects of whole body vibration exercise in the horizontal direction on balance and fear of falling in the elderly. [Methods] This study was a case series of 17 elderly individuals. Participants performed whole body vibration exercise in the horizontal direction using a whole body vibration device for 15 minutes a day, 3 times a week, for 6 weeks. At baseline and after the 6-week intervention, balance was measured using the Berg Balance Scale and Timed Up and Go test, and fear of falling was assessed using the Falls Efficacy Scale. [Results] After the intervention, significant improvements from baseline values in the Berg Balance Scale, Timed Up and Go test, and Falls Efficacy Scale were observed in the study participants. [Conclusion] Elderly individuals who performed whole body vibration exercise in the horizontal direction showed significant improvements in balance and fear of falling. However, the observed benefits of whole body vibration exercise in the horizontal direction need to be confirmed by additional studies. PMID:25140102

  4. Subsurface fracture spacing

    SciTech Connect

    Lorenz, J.C. ); Hill, R.E. )

    1991-01-01

    This study was undertaken in order to document and analyze the unique set of data on subsurface fracture characteristics, especially spacing, provided by the US Department of Energy's Slant Hole Completion Test well (SHCT-1) in the Piceance Basin, Colorado. Two hundred thirty-six (236) ft (71.9 m) of slant core and 115 ft (35.1 m) of horizontal core show irregular, but remarkably close, spacings for 72 natural fractures cored in sandstone reservoirs of the Mesaverde Group. Over 4200 ft (1280 m) of vertical core (containing 275 fractures) from the vertical Multiwell Experiment wells at the same location provide valuable information on fracture orientation, termination, and height, but only data from the SHCT-1 core allow calculations of relative fracture spacing. Within the 162-ft (49-m) thick zone of overlapping core from the vertical and deviated wellbores, only one fracture is present in vertical core whereas 52 fractures occur in the equivalent SHCT-1 core. The irregular distribution of regional-type fractures in these heterogeneous reservoirs suggests that measurements of average fracture spacing'' are of questionable value as direct input parameters into reservoir engineering models. Rather, deviated core provides data on the relative degree of fracturing, and confirms that cross fractures can be rare in the subsurface. 13 refs., 11 figs.

  5. Use of Cutting-Edge Horizontal and Underbalanced Drilling Technologies and Subsurface Seismic Techniques to Explore, Drill and Produce Reservoired Oil and Gas from the Fractured Monterey Below 10,000 ft in the Santa Maria Basin of California

    SciTech Connect

    George Witter; Robert Knoll; William Rehm; Thomas Williams

    2006-06-30

    This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were

  6. Use of Cutting-Edge Horizontal and Underbalanced Drilling Technologies and Subsurface Seismic Techniques to Explore, Drill and Produce Reservoired Oil and Gas from the Fractured Monterey Below 10,000 ft in the Santa Maria Basin of California

    SciTech Connect

    George Witter; Robert Knoll; William Rehm; Thomas Williams

    2005-09-29

    This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were

  7. USE OF CUTTING-EDGE HORIZONTAL AND UNDERBALANCED DRILLING TECHNOLOGIES AND SUBSURFACE SEISMIC TECHNIQUES TO EXPLORE, DRILL AND PRODUCE RESERVOIRED OIL AND GAS FROM THE FRACTURED MONTEREY BELOW 10,000 FT IN THE SANTA MARIA BASIN OF CALIFORNIA

    SciTech Connect

    George Witter; Robert Knoll; William Rehm; Thomas Williams

    2005-02-01

    This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area by Temblor Petroleum with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper

  8. Paracetamol removal in subsurface flow constructed wetlands

    NASA Astrophysics Data System (ADS)

    Ranieri, Ezio; Verlicchi, Paola; Young, Thomas M.

    2011-07-01

    SummaryIn this study two pilot scale Horizontal Subsurface Flow Constructed Wetlands (HSFCWs) near Lecce, Italy, planted with different macrophytes ( Phragmites australis and Typha latifolia) and an unplanted control were assessed for their effectiveness in removing paracetamol. Residence time distributions (RTDs) for the two beds indicated that the Typha bed was characterized by a void volume fraction (porosity) of 0.16 and exhibited more ideal plug flow behavior (Pe = 29.7) than the Phragmites bed (Pe = 26.7), which had similar porosity. The measured hydraulic residence times in the planted beds were 35.8 and 36.7 h when the flow was equal to 1 m 3/d. The Phragmites bed exhibited a range of paracetamol removals from 51.7% for a Hydraulic Loading Rate (HLR) of 240 mm/d to 87% with 120 mm/d HLR and 99.9% with 30 mm/d. The Typha bed showed a similar behavior with percentages of removal slightly lower, ranging from 46.7% (HLR of 240 mm/d) to >99.9% (hydraulic loading rate of 30 mm/d). At the same HLR values the unplanted bed removed between 51.3% and 97.6% of the paracetamol. In all three treatments the paracetamol removal was higher with flow of 1 m 3/d and an area of approx. 7.5 m 2 (half bed) than in the case of flow equal to 0.5 m 3/d with a surface treatment of approx. 3.75 m 2. A first order model for paracetamol removal was evaluated and half lives of 5.16 to 10.2 h were obtained.

  9. Parallel heater system for subsurface formations

    DOEpatents

    Harris, Christopher Kelvin; Karanikas, John Michael; Nguyen, Scott Vinh

    2011-10-25

    A heating system for a subsurface formation is disclosed. The system includes a plurality of substantially horizontally oriented or inclined heater sections located in a hydrocarbon containing layer in the formation. At least a portion of two of the heater sections are substantially parallel to each other. The ends of at least two of the heater sections in the layer are electrically coupled to a substantially horizontal, or inclined, electrical conductor oriented substantially perpendicular to the ends of the at least two heater sections.

  10. A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models

    USGS Publications Warehouse

    Spangler, L.H.; Dobeck, L.M.; Repasky, K.S.; Nehrir, A.R.; Humphries, S.D.; Keith, C.J.; Shaw, J.A.; Rouse, J.H.; Cunningham, A.B.; Benson, S.M.; Oldenburg, C.M.; Lewicki, J.L.; Wells, A.W.; Diehl, J.R.; Strazisar, B.R.; Fessenden, J.E.; Rahn, T.A.; Amonette, J.E.; Barr, J.L.; Pickles, W.L.; Jacobson, J.D.; Silver, E.A.; Male, E.J.; Rauch, H.W.; Gullickson, K.S.; Trautz, R.; Kharaka, Y.; Birkholzer, J.; Wielopolski, L.

    2010-01-01

    A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented. ?? 2009 The Author(s).

  11. A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models

    SciTech Connect

    Spangler, L.H.; Dobeck, L.M.; Nehrir, A.; Humphries, S.; Barr, J.; Keith, C.; Shaw, J.; Rouse, J.; Cunningham, A.; Benson, S.; Repasky, K.S.; Lewicki, J.; Wells, A.; Diehl, R.; Strazisar, B.; Fessenden, J.; Rahn, T.; Amonette, J.; Barr, J.; Pickles, W.; Jacobson, J.; Silver, E.; Male, E.; Rauch, H.; Gullickson, K.; Trautz, R.; Kharaka, Y.; Birkholzer, J.T.; Wielopolski, L.; Oldenburg, C.M.

    2009-10-20

    A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented.

  12. Comparing cost and performance of horizontal wells

    SciTech Connect

    Pocovi, A.S.; Gustavino, L.L. ); Pozzo, A.; Musmarra, J.A. )

    1991-02-01

    Argentina's state oil company, YPF, was forced through technical and economic constraints to undertake a four-well pilot horizontal drilling program in its Neuquen fields. This article discusses techniques used, the results and costs, and compares them to costs incurred by the area's original vertical wells.

  13. Electrical Subsurface Grounding Analysis

    SciTech Connect

    J.M. Calle

    2000-11-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements.

  14. Subsurface Microbiology and Biogeochemistry

    SciTech Connect

    Fredrickson, Jim K.; Fletcher, Madilyn

    2001-05-01

    Jim contributed a chapter to this book, in addition to co-editing it with Madilyn Fletcher. Fredrickson, J. K., and M. Fletcher. (eds.) 2001 Subsurface Microbiology and Biogeochemistry. Wiley-Liss, Inc., New York.

  15. Ceramic subsurface marker prototypes

    SciTech Connect

    Lukens, C.E.

    1985-05-02

    The client submitted 5 sets of porcelain and stoneware subsurface (radioactive site) marker prototypes (31 markers each set). The following were determined: compressive strength, thermal shock resistance, thermal crazing resistance, alkali resistance, color retention, and chemical resistance.

  16. Review of potential subsurface permeable barrier emplacement and monitoring technologies

    SciTech Connect

    Riggsbee, W.H.; Treat, R.L.; Stansfield, H.J.; Schwarz, R.M.; Cantrell, K.J.; Phillips, S.J.

    1994-02-01

    This report focuses on subsurface permeable barrier technologies potentially applicable to existing waste disposal sites. This report describes candidate subsurface permeable barriers, methods for emplacing these barriers, and methods used to monitor the barrier performance. Two types of subsurface barrier systems are described: those that apply to contamination.in the unsaturated zone, and those that apply to groundwater and to mobile contamination near the groundwater table. These barriers may be emplaced either horizontally or vertically depending on waste and site characteristics. Materials for creating permeable subsurface barriers are emplaced using one of three basic methods: injection, in situ mechanical mixing, or excavation-insertion. Injection is the emplacement of dissolved reagents or colloidal suspensions into the soil at elevated pressures. In situ mechanical mixing is the physical blending of the soil and the barrier material underground. Excavation-insertion is the removal of a soil volume and adding barrier materials to the space created. Major vertical barrier emplacement technologies include trenching-backfilling; slurry trenching; and vertical drilling and injection, including boring (earth augering), cable tool drilling, rotary drilling, sonic drilling, jetting methods, injection-mixing in drilled holes, and deep soil mixing. Major horizontal barrier emplacement technologies include horizontal drilling, microtunneling, compaction boring, horizontal emplacement, longwall mining, hydraulic fracturing, and jetting methods.

  17. Deep subsurface microbial processes

    USGS Publications Warehouse

    Lovley, D.R.; Chapelle, F.H.

    1995-01-01

    Information on the microbiology of the deep subsurface is necessary in order to understand the factors controlling the rate and extent of the microbially catalyzed redox reactions that influence the geophysical properties of these environments. Furthermore, there is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by man's activities, and there is a need to predict the extent to which microbial activity may remediate such contamination. Metabolically active microorganisms can be recovered from a diversity of deep subsurface environments. The available evidence suggests that these microorganisms are responsible for catalyzing the oxidation of organic matter coupled to a variety of electron acceptors just as microorganisms do in surface sediments, but at much slower rates. The technical difficulties in aseptically sampling deep subsurface sediments and the fact that microbial processes in laboratory incubations of deep subsurface material often do not mimic in situ processes frequently necessitate that microbial activity in the deep subsurface be inferred through nonmicrobiological analyses of ground water. These approaches include measurements of dissolved H2, which can predict the predominant microbially catalyzed redox reactions in aquifers, as well as geochemical and groundwater flow modeling, which can be used to estimate the rates of microbial processes. Microorganisms recovered from the deep subsurface have the potential to affect the fate of toxic organics and inorganic contaminants in groundwater. Microbial activity also greatly influences 1 the chemistry of many pristine groundwaters and contributes to such phenomena as porosity development in carbonate aquifers, accumulation of undesirably high concentrations of dissolved iron, and production of methane and hydrogen sulfide. Although the last decade has seen a dramatic increase in interest in deep subsurface microbiology, in comparison with the study of

  18. Site Recommendation Subsurface Layout

    SciTech Connect

    C.L. Linden

    2000-06-28

    The purpose of this analysis is to develop a Subsurface Facility layout that is capable of accommodating the statutory capacity of 70,000 metric tons of uranium (MTU), as well as an option to expand the inventory capacity, if authorized, to 97,000 MTU. The layout configuration also requires a degree of flexibility to accommodate potential changes in site conditions or program requirements. The objective of this analysis is to provide a conceptual design of the Subsurface Facility sufficient to support the development of the Subsurface Facility System Description Document (CRWMS M&O 2000e) and the ''Emplacement Drift System Description Document'' (CRWMS M&O 2000i). As well, this analysis provides input to the Site Recommendation Consideration Report. The scope of this analysis includes: (1) Evaluation of the existing facilities and their integration into the Subsurface Facility design. (2) Identification and incorporation of factors influencing Subsurface Facility design, such as geological constraints, thermal loading, constructibility, subsurface ventilation, drainage control, radiological considerations, and the Test and Evaluation Facilities. (3) Development of a layout showing an available area in the primary area sufficient to support both the waste inventories and individual layouts showing the emplacement area required for 70,000 MTU and, if authorized, 97,000 MTU.

  19. Horizontal drilling developments

    SciTech Connect

    Gust, D.

    1997-05-01

    The advantages of horizontal drilling are discussed. Use of horizontal drilling has climbed in the past half decade as technology and familiarity offset higher costs with higher production rates and greater recoveries from new and existing wells. In essence, all types of horizontal wells expose a larger section of the reservoir to the wellbore with a resulting increase in flow rates. (A horizontal well may also be drilled to provide coning control or to intersect vertical fractures.) Thus, drilling horizontally, both onshore and offshore, reduces the number of wells necessary to develop a field.

  20. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-12-12

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a

  1. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-11-16

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a

  2. Best Practice -- Subsurface Investigations

    SciTech Connect

    Clark Scott

    2010-03-01

    These best practices for Subsurface Survey processes were developed at the Idaho National Laboratory (INL) and later shared and formalized by a sub-committee, under the Electrical Safety Committee of EFCOG. The developed best practice is best characterized as a Tier II (enhanced) survey process for subsurface investigations. A result of this process has been an increase in the safety and lowering of overall cost, when utility hits and their related costs are factored in. The process involves improving the methodology and thoroughness of the survey and reporting processes; or improvement in tool use rather than in the tools themselves. It is hoped that the process described here can be implemented at other sites seeking to improve their Subsurface Investigation results with little upheaval to their existing system.

  3. The Serpentinite Subsurface Microbiome

    NASA Astrophysics Data System (ADS)

    Schrenk, M. O.; Nelson, B. Y.; Brazelton, W. J.

    2011-12-01

    Microbial habitats hosted in ultramafic rocks constitute substantial, globally-distributed portions of the subsurface biosphere, occurring both on the continents and beneath the seafloor. The aqueous alteration of ultramafics, in a process known as serpentinization, creates energy rich, high pH conditions, with low concentrations of inorganic carbon which place fundamental constraints upon microbial metabolism and physiology. Despite their importance, very few studies have attempted to directly access and quantify microbial activities and distributions in the serpentinite subsurface microbiome. We have initiated microbiological studies of subsurface seeps and rocks at three separate continental sites of serpentinization in Newfoundland, Italy, and California and compared these results to previous analyses of the Lost City field, near the Mid-Atlantic Ridge. In all cases, microbial cell densities in seep fluids are extremely low, ranging from approximately 100,000 to less than 1,000 cells per milliliter. Culture-independent analyses of 16S rRNA genes revealed low-diversity microbial communities related to Gram-positive Firmicutes and hydrogen-oxidizing bacteria. Interestingly, unlike Lost City, there has been little evidence for significant archaeal populations in the continental subsurface to date. Culturing studies at the sites yielded numerous alkaliphilic isolates on nutrient-rich agar and putative iron-reducing bacteria in anaerobic incubations, many of which are related to known alkaliphilic and subsurface isolates. Finally, metagenomic data reinforce the culturing results, indicating the presence of genes associated with organotrophy, hydrogen oxidation, and iron reduction in seep fluid samples. Our data provide insight into the lifestyles of serpentinite subsurface microbial populations and targets for future quantitative exploration using both biochemical and geochemical approaches.

  4. Terrestrial Subsurface Ecosystem

    SciTech Connect

    Wilkins, Michael J.; Fredrickson, Jim K.

    2015-10-15

    The Earth’s crust is a solid cool layer that overlays the mantle, with a varying thickness of between 30-50 km on continental plates, and 5-10 km on oceanic plates. Continental crust is composed of a variety of igneous, metamorphic, and sedimentary rocks that weather and re-form over geologic cycles lasting millions to billions of years. At the crust surface, these weathered minerals and organic material combine to produce a variety of soils types that provide suitable habitats and niches for abundant microbial diversity (see Chapter 4). Beneath this soil zone is the subsurface. Once thought to be relatively free of microorganisms, recent estimates have calculated that between 1016-1017 g C biomass (2-19% of Earth’s total biomass) may be present in this environment (Whitman et al., 1998;McMahon and Parnell, 2014). Microbial life in the subsurface exists across a wide range of habitats: in pores associated with relatively shallow unconsolidated aquifer sediments to fractures in bedrock formations that are more than a kilometer deep, where extreme lithostatic pressures and temperatures are encountered. While these different environments contain varying physical and chemical conditions, the absence of light is a constant. Despite this, diverse physiologies and metabolisms enable microorganisms to harness energy and carbon for growth in water-filled pore spaces and fractures. Carbon and other element cycles are driven by microbial activity, which has implications for both natural processes and human activities in the subsurface, e.g., bacteria play key roles in both hydrocarbon formation and degradation. Hydrocarbons are a major focus for human utilization of the subsurface, via oil and gas extraction and potential geologic CO2 sequestration. The subsurface is also utilized or being considered for sequestered storage of high-level radioactive waste from nuclear power generation and residual waste from past production of weapons grade nuclear materials. While our

  5. Subsurface connection methods for subsurface heaters

    DOEpatents

    Vinegar, Harold J.; Bass, Ronald Marshall; Kim, Dong Sub; Mason, Stanley Leroy; Stegemeier, George Leo; Keltner, Thomas Joseph; Carl, Jr., Frederick Gordon

    2010-12-28

    A system for heating a subsurface formation is described. The system includes a first elongated heater in a first opening in the formation. The first elongated heater includes an exposed metal section in a portion of the first opening. The portion is below a layer of the formation to be heated. The exposed metal section is exposed to the formation. A second elongated heater is in a second opening in the formation. The second opening connects to the first opening at or near the portion of the first opening below the layer to be heated. At least a portion of an exposed metal section of the second elongated heater is electrically coupled to at least a portion of the exposed metal section of the first elongated heater in the portion of the first opening below the layer to be heated.

  6. Mars penetrator: Subsurface science mission

    NASA Technical Reports Server (NTRS)

    Lumpkin, C. K.

    1974-01-01

    A penetrator system to emplace subsurface science on the planet Mars is described. The need for subsurface science is discussed, and the technologies for achieving successful atmospheric entry, Mars penetration, and data retrieval are presented.

  7. Subsurface Ice Probe

    NASA Technical Reports Server (NTRS)

    Hecht, Michael; Carsey, Frank

    2005-01-01

    The subsurface ice probe (SIPR) is a proposed apparatus that would bore into ice to depths as great as hundreds of meters by melting the ice and pumping the samples of meltwater to the surface. Originally intended for use in exploration of subsurface ice on Mars and other remote planets, the SIPR could also be used on Earth as an alternative to coring, drilling, and melting apparatuses heretofore used to sample Arctic and Antarctic ice sheets. The SIPR would include an assembly of instrumentation and electronic control equipment at the surface, connected via a tether to a compact assembly of boring, sampling, and sensor equipment in the borehole (see figure). Placing as much equipment as possible at the surface would help to attain primary objectives of minimizing power consumption, sampling with high depth resolution, and unobstructed imaging of the borehole wall. To the degree to which these requirements would be satisfied, the SIPR would offer advantages over the aforementioned ice-probing systems.

  8. Subsurface contaminants focus area

    SciTech Connect

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  9. Applications of subsurface microscopy.

    PubMed

    Tetard, Laurene; Passian, Ali; Farahi, Rubye H; Voy, Brynn H; Thundat, Thomas

    2012-01-01

    Exploring the interior of a cell is of tremendous importance in order to assess the effects of nanomaterials on biological systems. Outside of a controlled laboratory environment, nanomaterials will most likely not be conveniently labeled or tagged so that their translocation within a biological system cannot be easily identified and quantified. Ideally, the characterization of nanomaterials within a cell requires a nondestructive, label-free, and subsurface approach. Subsurface nanoscale imaging represents a real challenge for instrumentation. Indeed the tools available for high resolution characterization, including optical, electron or scanning probe microscopies, mainly provide topography images or require taggants that fluoresce. Although the intercellular environment holds a great deal of information, subsurface visualization remains a poorly explored area. Recently, it was discovered that by mechanically perturbing a sample, it was possible to observe its response in time with nanoscale resolution by probing the surface with a micro-resonator such as a microcantilever probe. Microcantilevers are used as the force-sensing probes in atomic force microscopy (AFM), where the nanometer-scale probe tip on the microcantilever interacts with the sample in a highly controlled manner to produce high-resolution raster-scanned information of the sample surface. Taking advantage of the existing capabilities of AFM, we present a novel technique, mode synthesizing atomic force microscopy (MSAFM), which has the ability to probe subsurface structures such as non-labeled nanoparticles embedded in a cell. In MSAFM mechanical actuators (PZTs) excite the probe and the sample at different frequencies as depicted in the first figure of this chapter. The nonlinear nature of the tip-sample interaction, at the point of contact of the probe and the surface of the sample, in the contact mode AFM configuration permits the mixing of the elastic waves. The new dynamic system comprises new

  10. Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

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

    Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Detail, Vertical Cross Bracing-End Detail - Cumberland Covered Bridge, Spanning Mississinewa River, Matthews, Grant County, IN

  11. Method of assisting surface lift of heated subsurface viscous petroleum

    SciTech Connect

    Anderson, D.J.

    1984-11-06

    A method and apparatus is described for producing viscous petroleum from a subsurface formation. The apparatus includes a generally horizontal cased well through the subsurface formation with injection and production tubings within the well. The casing is perforated and the inner tubings carry a movable packer and a rotatable agitator. The method comprises injecting a heating and drive fluid for moving heated viscous petroleum through the perforations in the casing and into the well for production to the wellhead. Production is monitored for the ratio of produced packer fluid and viscous petroleum. Based on that ratio, the packer is moved within the casing to positions along the horizontal well to maximize production of petroleum. The rotatable agitator assists in removal from the well bore of formation solids produced with the viscous petroleum.

  12. Elf cites 5 advantages of horizontal drilling

    SciTech Connect

    Not Available

    1984-06-01

    ELF Aquitaine used horizontal drilling during a pilot test program to bring commercial production from its Rospo Mare oil discovery in the Adriatic, which would have been a costly disappointment if drilled by a conventional vertical well bore. Rospo Mare is a large reservoir containing a top column of highly viscous crude underlain by a water column. The company felt that a well bore that penetrated the reservoir vertically would bring early flooding of the oil column and yield only water. By penetrating the reservoir with a horizontal well drilled high in the oil column, the well successfully produced on numerous tests from Oct. 1982 until the end of the test program in 1983. Production was termed excellent, with productivity during tests reportedly reaching ca 15 times the rate produced from nearby vertical wells. However, ELF said the results usually average ca 5 times the usual rate of vertical wells.

  13. Subsurface Biogeochemistry of Actinides

    SciTech Connect

    Kersting, Annie B.; Zavarin, Mavrik

    2016-06-29

    A major scientific challenge in environmental sciences is to identify the dominant processes controlling actinide transport in the environment. It is estimated that currently, over 2200 metric tons of plutonium (Pu) have been deposited in the subsurface worldwide, a number that increases yearly with additional spent nuclear fuel (Ewing et al., 2010). Plutonium has been shown to migrate on the scale of kilometers, giving way to a critical concern that the fundamental biogeochemical processes that control its behavior in the subsurface are not well understood (Kersting et al., 1999; Novikov et al., 2006; Santschi et al., 2002). Neptunium (Np) is less prevalent in the environment; however, it is predicted to be a significant long-term dose contributor in high-level nuclear waste. Our focus on Np chemistry in this Science Plan is intended to help formulate a better understanding of Pu redox transformations in the environment and clarify the differences between the two long-lived actinides. The research approach of our Science Plan combines (1) Fundamental Mechanistic Studies that identify and quantify biogeochemical processes that control actinide behavior in solution and on solids, (2) Field Integration Studies that investigate the transport characteristics of Pu and test our conceptual understanding of actinide transport, and (3) Actinide Research Capabilities that allow us to achieve the objectives of this Scientific Focus Area (SFA and provide new opportunities for advancing actinide environmental chemistry. These three Research Thrusts form the basis of our SFA Science Program (Figure 1).

  14. Horizontal Advanced Tensiometer

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2004-06-22

    An horizontal advanced tensiometer is described that allows the monitoring of the water pressure of soil positions, particularly beneath objects or materials that inhibit the use of previous monitoring wells. The tensiometer includes a porous cup, a pressure transducer (with an attached gasket device), an adaptive chamber, at least one outer guide tube which allows access to the desired horizontal position, a transducer wire, a data logger and preferably an inner guide tube and a specialized joint which provides pressure on the inner guide tube to maintain the seal between the gasket of the transducer and the adaptive chamber.

  15. Nonintrusive subsurface surveying capability

    SciTech Connect

    Tunnell, T.W.; Cave, S.P.

    1994-06-01

    This presentation describes the capabilities of a ground-pentrating radar (GPR) system developed by EG&G Energy Measurements (EM), a prime contractor to the Department of Energy (DOE). The focus of the presentation will be on the subsurface survey of DOE site TA-21 in Los Alamos, New Mexico. EG&G EM developed the system for the Department of Defense. The system is owned by the Department of the Army and currently resides at KO in Albuquerque. EM is pursuing efforts to transfer this technology to environmental applications such as waste-site characterization with DOE encouragement. The Army has already granted permission to use the system for the waste-site characterization activities.

  16. Containment of subsurface contaminants

    DOEpatents

    Corey, J.C.

    1994-09-06

    A barrier is disclosed for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates. 5 figs.

  17. Containment of subsurface contaminants

    DOEpatents

    Corey, John C.

    1994-01-01

    A barrier for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates.

  18. Reservoir visualization for geosteering of horizontal wells

    SciTech Connect

    Bryant, I.D.; Baygun, B.; Frass, M.; Casco, R.

    1996-08-01

    Horizontal infill wells in the Lower Lagunillas reservoir of Bloque IV, Lake Maracaibo are being drilled in thin, oil-bearing zones that have been bypassed by gas. Steering the horizontal sections of these wells requires high resolution reservoir models that can be updated during drilling. An example from well VLD-1152 serves to illustrate how these models are generated and used. Resistivity images collected by wireline and logging-while-drilling (LWD) tools in the pilot well formed the basis of prejob, high resolution modeling of the formation properties. 3-D seismic data and data from an offset vertical seismic profile collected in the pilot well provided the structural model. During drilling information from cuttings and LWD tools was used to continuously update these models. After the well had been drilled, analysis of LWD resistivity images provided a detailed model of the relationship between the well trajectory and the dip of the formation. This information is used to improve interpretation of the LWD logs to provide a petrophysical evaluation of the well.

  19. Subsurface Samples: Collection and Processing

    SciTech Connect

    Long, Philip E.; Griffin, W. Timothy; Phelps, Tommy J.

    2002-12-01

    Microbiological data, interpretation, and conclusions from subsurface samples ultimately depend on the quality and representative character of the samples. Subsurface samples for environmental microbiology ideally contain only the microbial community and geochemical properties that are representative of the subsurface environment from which the sample was taken. To that end, sample contamination by exogenous microorganisms or chemical constituents must be eliminated or minimized, and sample analyses need to begin before changes in the microbial community or geochemical characteristics occur. This article presents sampling methods and sample processing techniques for collecting representative samples from a range of subsurface environments. Factors that should be considered when developing a subsurface sampling program are discussed, including potential benefits, costs, and limitations enabling researchers to evaluate the techniques that are presented and match them to their project requirements. Methods and protocols to address coring, sampling, processing and quality assessment issues are presented.

  20. Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

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

    Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Joint, Vertical Cross Bracing End Detail - Ceylon Covered Bridge, Limberlost Park, spanning Wabash River at County Road 900 South, Geneva, Adams County, IN

  1. Appendix to theory of radio-frequency interferometry in geophysical subsurface probing, numerical results

    NASA Technical Reports Server (NTRS)

    Kong, J. A.; Tsang, L.

    1974-01-01

    A series of interference and radiation patterns are presented for radio interferometry in subsurface probing. The interference patterns are due both to a vertical magnetic dipole and to a horizontal electric dipole. Mode solutions are also presented for layer thickness equal to 1 wavelength, as well as for thin layers.

  2. Microbial Transport in the Subsurface

    SciTech Connect

    Ginn, Timothy R.; Camesano, Terri; Scheibe, Timothy D.; Nelson, Kirk B.; Clement, T. P.; Wood, Brian D.

    2005-12-01

    In this article we focus on the physical, chemical, and biological processes involved in the transport of bacteria in the saturated subsurface. We will first review conceptual models of bacterial phases in the subsurface, and then the processes controlling fate and transport on short (e.g., bioremediation) time scales. Finally we briefly review field bacterial transport experiments and discuss a number of issues that impact the application of current process descriptions and models at the field scale.

  3. Bioventing approach to remediate a gasoline contaminated subsurface. Book chapter

    SciTech Connect

    Kampbell, D.H.; Wilson, J.T.; Griffin, C.J.

    1992-01-01

    Bioventing is a subsurface process using an air stream to enhance biodegradation of oily contaminants. Two pilot-scale bioventing systems were installed at a field site. Process operations began in October 1990. The field site is located at an air station. A spill in 1969 of about 100,000 kilograms aviation gasoline was caused by a broken underground transfer line. A major portion of the spilled product still persists as an oily-phase residue in a 80x360 meter plume. The subsurface is a uniform beach sand with the ground water level near five meters. Prior to startup of the venting systems, a grass cover was established and a nutrient solution was dispersed throughout the unsaturated subsurface. Subsurface air flow patterns are being determined with a tracer gas of sulfur hexafloride. Soil gas, core material, and underground water are being monitored to determine the extent of remediation. Objectives of the study are to demonstrate that surface emissions of gasoline are minimal, oily residue will be reduced to <100 mg fuel carbon/Kg core material, and the process will be applicable to full-scale remediation. Flow rate is based on a calculated residence time of 24 hours. Surface emission of fuel hydrocarbons have not exceeded 1 micrograms/liter soil gas.

  4. Demonstration of a utility industry horizontal drilling system: Horizontal well AMH-5 installation report

    SciTech Connect

    Not Available

    1992-12-31

    The Department of Energy`s Office of Technology Development initiated an integrated demonstration of innovative technologies and systems for cleanup of VOCs in soils and groundwater at the Savannah River Site (SRS) in 1989. The overall goal of the program is demonstration of multiple technologies and systems in the fields of drilling, characterization, monitoring, and remediation at a single test bed. Innovative technologies are compared to one another and to baseline technologies in terms of technical performance and cost effectiveness. Transfer of successfully demonstrated technologies and systems to DOE environmental restoration organizations, to other government agencies, and to industry is a critical part of the program. Directional drilling has been shown to be a successful technique for enhancing access to the subsurface, thus improving remediation systems, especially remediation systems which perform in situ. Demonstration of an innovative directional drilling system at the Integrated Demonstration Site at the SRS, was initiated in June of 1992. The directional drilling system was designed to install an in situ remediation system. The drilling system is an experimental compaction/dry drilling technique developed by Charles Machine Works (Ditch Witch{reg_sign}) of Perry, Oklahoma. A horizontal well was installed in the M Area of the SRS below and parallel to an abandoned tile process sewer line. The installation of the horizontal well was a two-part process. Part one consisted of drilling the borehole, and part two was the horizontal well completion.

  5. Horizontal baffle for nuclear reactors

    DOEpatents

    Rylatt, John A.

    1978-01-01

    A horizontal baffle disposed in the annulus defined between the core barrel and the thermal liner of a nuclear reactor thereby physically separating the outlet region of the core from the annular area below the horizontal baffle. The horizontal baffle prevents hot coolant that has passed through the reactor core from thermally damaging apparatus located in the annulus below the horizontal baffle by utilizing the thermally induced bowing of the horizontal baffle to enhance sealing while accommodating lateral motion of the baffle base plate.

  6. Subsurface Geotechnical Parameters Report

    SciTech Connect

    D. Rigby; M. Mrugala; G. Shideler; T. Davidsavor; J. Leem; D. Buesch; Y. Sun; D. Potyondy; M. Christianson

    2003-12-17

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  7. HORIZONTAL BOILING REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  8. ASSESSMENT OF THE SUBSURFACE FATE OF MONOETHANOLAMINE

    SciTech Connect

    James A. Sorensen; John R. Gallagher; Lori G. Kays

    2000-05-01

    Burial of amine reclaimer unit sludges and system filters has resulted in contamination of soil at the CanOxy Okotoks decommissioned sour gas-processing plant with amines, amine byproducts, and salts. A three-phase research program was devised to investigate the natural attenuation process that controls the subsurface transport and fate of these contaminants and to apply the results toward the development of a strategy for the remediation of this type of contamination in soils. Phase I experimental activities examined interactions between monoethanolamine (MEA) and sediment, the biodegradability of MEA in soils at various concentrations and temperatures, and the biodegradability of MEA sludge contamination in a soil slurry bioreactor. The transport and fate of MEA in the subsurface was found to be highly dependant on the nature of the release, particularly MEA concentration and conditions of the subsurface environment, i.e., pH, temperature, and oxygen availability. Pure compound biodegradation experiments in soil demonstrated rapid biodegradation of MEA under aerobic conditions and moderate temperatures (>6 C). Phase II landfarming activities confirmed that these contaminants are readily biodegradable in soil under ideal laboratory conditions, yet considerable toxicity was observed in the remaining material. Examination of water extracts from the treated soil suggested that the toxicity is water-soluble. Phase II activities led to the conclusion that landfarming is not the most desirable bioremediation technique; however, an engineered biopile with a leachate collection system could remove the remaining toxic fraction from the soil. Phase III was initiated to conduct field-based experimental activities to examine the optimized remediation technology. A pilot-scale engineered biopile was constructed at a decommissioned gas-sweetening facility in Okotoks, Alberta, Canada. On the basis of a review of the analytical and performance data generated from soil and

  9. Tangible Exploration of Subsurface Data

    NASA Astrophysics Data System (ADS)

    Petrasova, A.; Harmon, B.; Mitasova, H.; White, J.

    2014-12-01

    Since traditional subsurface visualizations using 2D maps, profiles or charts can be difficult to interpret and often do not convey information in an engaging form, scientists are interested in developing alternative visualization techniques which would help them communicate the subsurface volume data with students and general public. We would like to present new technique for interactive visualization of subsurface using Tangible geospatial modeling and visualization system (Tangeoms). It couples a physical, three-dimensional model with geospatial modeling and analysis through a cycle of scanning and projection. Previous applications of Tangeoms were exploring the impact of terrain modifications on surface-based geophysical processes, such as overland water flow, sediment transport, and also on viewsheds, cast shadows or solar energy potential. However, Tangeoms can serve as a tool for exploring subsurface as well. By creating a physical sand model of a study area, removing the sand from different parts of the model and projecting the computed cross-sections, we can look under the ground as if we were at an excavation site, and see the actual data represented as a 3D raster in that particular part of the model. Depending on data availability, we can also incorporate temporal dimension. Our method is an intuitive and natural way of exploring subsurface data and for users, it represents an alternative to more abstract 3D computer visualization tools, by offering direct, tangible interface.

  10. Pilot performance

    NASA Technical Reports Server (NTRS)

    Nicholls, Jennifer

    1988-01-01

    For many years, the emphasis has been placed on the performance of the aircraft, rather than on those who fly the aircraft. This is largely due to the relative safety of flying. Just in the last few years there have been several major accidents that have shown that flying is not quite as safe as it was thought to be. Sixty-five percent of these accidents are a result of pilot performance decrements, and so it is obvious that there is a need to reduce that figure. A study has been mandated to evaluate the performance of pilots. This includes workload, circadium rhythms, jet lag, and any other factors which might affect a pilot's performance in the cockpit. The purpose of this study is to find out when and why the decrement in a pilot's performance occur and how to remedy the situation.

  11. Using soil moisture and spatial yield patterns to identify subsurface flow pathways.

    PubMed

    Gish, T J; Walthall, C L; Daughtry, C S T; Kung, K-J S

    2005-01-01

    Subsurface soil water dynamics can influence crop growth and the fate of surface-applied fertilizers and pesticides. Recently, a method was proposed using only ground-penetrating radar (GPR) and digital elevation maps (DEMs) to identify locations where subsurface water converged into discrete pathways. For this study, the GPR protocol for identifying horizontal subsurface flow pathways was extended to a 3.2-ha field, uncertainty is discussed, and soil moisture and yield patterns are presented as confirming evidence of the extent of the subsurface flow pathways. Observed soil water contents supported the existence of discrete preferential funnel flow processes occurring near the GPR-identified preferential flow pathways. Soil moisture also played a critical role in the formation of corn (Zea mays L.) grain yield patterns with yield spatial patterns being similar for mild and severe drought conditions. A buffer zone protocol was introduced that allowed the impact of subsurface flow pathways on corn grain yield to be quantified. Results indicate that when a GPR-identified subsurface clay layer was within 2 m of the soil surface, there was a beneficial impact on yield during a drought year. Furthermore, the buffer zone analysis demonstrated that corn grain yields decreased as the horizontal distance from the GPR-identified subsurface flow pathways increased during a drought year. Averaged real-time soil moisture contents at 0.1 m also decreased with increasing distance from the GPR-identified flow pathways. This research suggests that subsurface flow pathways exist and influence soil moisture and corn grain yield patterns.

  12. Magnetotelluric Sensor Development for Planetary Subsurface Exploration

    NASA Astrophysics Data System (ADS)

    Fuqua, H.; Delory, G. T.; De Pater, I.; Grimm, R. E.

    2012-12-01

    Electromagnetic (EM) Sounding is a powerful geophysical investigation technique capable of constraining planetary subsurface structure, including core size, mantle and crustal temperature profiles, and the distribution of electrical conductivity at depth. Natural sources of EM activity, including solar wind turbulence and plasma waves, can induce electric and magnetic fields in the Moon and other small bodies. These induced fields respond according to the electrical conductivity as a function of skin depth of the body in question. In a branch of EM Sounding known as Magnetotellurics (MT), measurements of the horizontal electric and magnetic fields at the planetary surface are inverted to produce constraints on the interior. MT is particularly worthwhile in that geophysically meaningful results can be obtained from a single station, thus avoiding network mission architectures. While surface magnetic field measurements were taken on the Moon during the Apollo era, to date no measurements of the surface horizontal electric field have been attempted. However electric field measurements on the lunar surface should be feasible given their long successful history on spacecraft missions in similar environments. Building upon the heritage of electric field sensor technology at the UC Berkeley Space Sciences Laboratory, we describe a development plan for this instrument from component level to a fully functional instrument assembly for use in EM sounding, highlighting operational requirements, science capabilities, required testing, anticipated results and challenges to overcome. Upon development, this lander electric field sensor will enable future MT surveys on the Moon, and will provide a new exploration method for other small airless bodies from a single station.

  13. Endoscopic subsurface imaging in tissues

    SciTech Connect

    Demos, S G; Staggs, M; Radousky, H B

    2001-02-12

    The objective of this work is to develop endoscopic subsurface optical imaging technology that will be able to image different tissue components located underneath the surface of the tissue at an imaging depth of up to 1 centimeter. This effort is based on the utilization of existing technology and components developed for medical endoscopes with the incorporation of the appropriate modifications to implement the spectral and polarization difference imaging technique. This subsurface imaging technique employs polarization and spectral light discrimination in combination with image processing to remove a large portion of the image information from the outer layers of the tissue which leads to enhancement of the contrast and image quality of subsurface tissue structures.

  14. Measuring isotropic subsurface light transport.

    PubMed

    Happel, Kathrin; Dörsam, Edgar; Urban, Philipp

    2014-04-21

    Subsurface light transport can affect the visual appearance of materials significantly. Measuring and modeling this phenomenon is crucial for accurately reproducing colors in printing or for rendering translucent objects on displays. In this paper, we propose an apparatus to measure subsurface light transport employing a reference material to cancel out adverse signals that may bias the results. In contrast to other approaches, the setup enables improved focusing on rough surfaces (e.g. uncoated paper). We derive a measurement equation that may be used to deduce the point spread function (PSF) of subsurface light transport. Main contributions are the usage of spectrally-narrowband exchangeable LEDs allowing spectrally-resolved measurements and an approach based on quadratic programming for reconstructing PSFs in the case of isotropic light transport.

  15. Subsurface microbial habitats on Mars

    NASA Technical Reports Server (NTRS)

    Boston, P. J.; Mckay, C. P.

    1991-01-01

    We developed scenarios for shallow and deep subsurface cryptic niches for microbial life on Mars. Such habitats could have considerably prolonged the persistence of life on Mars as surface conditions became increasingly inhospitable. The scenarios rely on geothermal hot spots existing below the near or deep subsurface of Mars. Recent advances in the comparatively new field of deep subsurface microbiology have revealed previously unsuspected rich aerobic and anaerobic microbal communities far below the surface of the Earth. Such habitats, protected from the grim surface conditions on Mars, could receive warmth from below and maintain water in its liquid state. In addition, geothermally or volcanically reduced gases percolating from below through a microbiologically active zone could provide the reducing power needed for a closed or semi-closed microbial ecosystem to thrive.

  16. Horizontal microscopy in square capillaries

    NASA Astrophysics Data System (ADS)

    Moroz, Pavel E.

    1992-07-01

    Intracellular protoplasmic movements may, due to gravity, have a vertical component greater or different from the horizontal one. This makes horizontal microscopy indispensable in the search for the cellular sensor of gravity. The possibility of the latter being a cell organelle assigns special significance to high-resolution microscopy. A horizontal suction device for picking up a cell and its high-resolution horizontal microscopy in a rectangular capillary may be helpful for detection of gravity-related shifts of cellular organelles in vivo.

  17. Towed Subsurface Optical Communications Buoy

    NASA Technical Reports Server (NTRS)

    Stirbl, Robert C.; Farr, William H.

    2013-01-01

    The innovation allows critical, high-bandwidth submarine communications at speed and depth. This reported innovation is a subsurface optical communications buoy, with active neutral buoyancy and streamlined flow surface veins for depth control. This novel subsurface positioning for the towed communications buoy enables substantial reduction in water-absorption and increased optical transmission by eliminating the intervening water absorption and dispersion, as well as by reducing or eliminating the beam spread and the pulse spreading that is associated with submarine-launched optical beams.

  18. Decadal variation and trends in subsurface salinity from 1960 to 2012 in the northern South China Sea

    NASA Astrophysics Data System (ADS)

    Zeng, Lili; Wang, Dongxiao; Xiu, Peng; Shu, Yeqiang; Wang, Qiang; Chen, Ju

    2016-12-01

    Observations suggest that subsurface waters in the northern South China Sea exhibited substantial low-frequency variability, with a striking decadal change in the southern limit of the 34.6 practical salinity unit (psu) isohaline. Long-term freshening of the subsurface waters, started in 1960, was followed by salinification from 1975, and freshening occurred again from 1993 to 2012. The linear trends were -0.0076, 0.0100, and -0.0078 psu/yr, respectively. An analysis of the subsurface salinity budget reveals that the main underlying contributors to subsurface salinity are horizontal advection and vertical entrainment. In particular, advection driven by the Luzon Strait transport and vertical entrainment from the mixed layer are the key factors controlling variations on subsurface salinity. Diagnosis of the salinity budget further suggests that entrainment from the mixed layer played a more important role in the freshening periods than in the salinifying period.

  19. Inferring Horizontal Gene Transfer

    PubMed Central

    Lassalle, Florent; Dessimoz, Christophe

    2015-01-01

    Horizontal or Lateral Gene Transfer (HGT or LGT) is the transmission of portions of genomic DNA between organisms through a process decoupled from vertical inheritance. In the presence of HGT events, different fragments of the genome are the result of different evolutionary histories. This can therefore complicate the investigations of evolutionary relatedness of lineages and species. Also, as HGT can bring into genomes radically different genotypes from distant lineages, or even new genes bearing new functions, it is a major source of phenotypic innovation and a mechanism of niche adaptation. For example, of particular relevance to human health is the lateral transfer of antibiotic resistance and pathogenicity determinants, leading to the emergence of pathogenic lineages [1]. Computational identification of HGT events relies upon the investigation of sequence composition or evolutionary history of genes. Sequence composition-based ("parametric") methods search for deviations from the genomic average, whereas evolutionary history-based ("phylogenetic") approaches identify genes whose evolutionary history significantly differs from that of the host species. The evaluation and benchmarking of HGT inference methods typically rely upon simulated genomes, for which the true history is known. On real data, different methods tend to infer different HGT events, and as a result it can be difficult to ascertain all but simple and clear-cut HGT events. PMID:26020646

  20. Geomechanics of subsurface water withdrawal and injection

    NASA Astrophysics Data System (ADS)

    Gambolati, Giuseppe; Teatini, Pietro

    2015-06-01

    Land subsidence and uplift, ground ruptures, and induced seismicity are the principal geomechanic effects of groundwater withdrawal and injection. The major environmental consequence of groundwater pumping is anthropogenic land subsidence. The first observation concerning land settlement linked to subsurface processes was made in 1926 by the American geologists Pratt and Johnson, who wrote that "the cause of subsidence is to be found in the extensive extraction of fluid from beneath the affected area." Since then, impressive progress has been made in terms of: (a) recognizing the basic hydrologic and geomechanic principles underlying the occurrence; (b) measuring aquifer compaction and ground displacements, both vertical and horizontal; (c) modeling and predicting the past and future event; and (d) mitigating environmental impact through aquifer recharge and/or surface water injection. The first milestone in the theory of pumped aquifer consolidation was reached in 1923 by Terzaghi, who introduced the principle of "effective intergranular stress." In the early 1970s, the emerging computer technology facilitated development of the first mathematical model of the subsidence of Venice, made by Gambolati and Freeze. Since then, the comprehension, measuring, and simulation of the occurrence have improved dramatically. More challenging today are the issues of ground ruptures and induced/triggered seismicity, which call for a shift from the classical continuum approach to discontinuous mechanics. Although well known for decades, anthropogenic land subsidence is still threatening large urban centers and deltaic areas worldwide, such as Bangkok, Jakarta, and Mexico City, at rates in the order of 10 cm/yr.

  1. Is the Genetic Landscape of the Deep Subsurface Biosphere Affected by Viruses?

    PubMed Central

    Anderson, Rika E.; Brazelton, William J.; Baross, John A.

    2011-01-01

    Viruses are powerful manipulators of microbial diversity, biogeochemistry, and evolution in the marine environment. Viruses can directly influence the genetic capabilities and the fitness of their hosts through the use of fitness factors and through horizontal gene transfer. However, the impact of viruses on microbial ecology and evolution is often overlooked in studies of the deep subsurface biosphere. Subsurface habitats connected to hydrothermal vent systems are characterized by constant fluid flux, dynamic environmental variability, and high microbial diversity. In such conditions, high adaptability would be an evolutionary asset, and the potential for frequent host–virus interactions would be high, increasing the likelihood that cellular hosts could acquire novel functions. Here, we review evidence supporting this hypothesis, including data indicating that microbial communities in subsurface hydrothermal fluids are exposed to a high rate of viral infection, as well as viral metagenomic data suggesting that the vent viral assemblage is particularly enriched in genes that facilitate horizontal gene transfer and host adaptability. Therefore, viruses are likely to play a crucial role in facilitating adaptability to the extreme conditions of these regions of the deep subsurface biosphere. We also discuss how these results might apply to other regions of the deep subsurface, where the nature of virus–host interactions would be altered, but possibly no less important, compared to more energetic hydrothermal systems. PMID:22084639

  2. Is the genetic landscape of the deep subsurface biosphere affected by viruses?

    PubMed

    Anderson, Rika E; Brazelton, William J; Baross, John A

    2011-01-01

    Viruses are powerful manipulators of microbial diversity, biogeochemistry, and evolution in the marine environment. Viruses can directly influence the genetic capabilities and the fitness of their hosts through the use of fitness factors and through horizontal gene transfer. However, the impact of viruses on microbial ecology and evolution is often overlooked in studies of the deep subsurface biosphere. Subsurface habitats connected to hydrothermal vent systems are characterized by constant fluid flux, dynamic environmental variability, and high microbial diversity. In such conditions, high adaptability would be an evolutionary asset, and the potential for frequent host-virus interactions would be high, increasing the likelihood that cellular hosts could acquire novel functions. Here, we review evidence supporting this hypothesis, including data indicating that microbial communities in subsurface hydrothermal fluids are exposed to a high rate of viral infection, as well as viral metagenomic data suggesting that the vent viral assemblage is particularly enriched in genes that facilitate horizontal gene transfer and host adaptability. Therefore, viruses are likely to play a crucial role in facilitating adaptability to the extreme conditions of these regions of the deep subsurface biosphere. We also discuss how these results might apply to other regions of the deep subsurface, where the nature of virus-host interactions would be altered, but possibly no less important, compared to more energetic hydrothermal systems.

  3. Understanding Horizontal Governance. Research Brief

    ERIC Educational Resources Information Center

    Ferguson, Daniel

    2009-01-01

    Horizontal governance is an umbrella term that covers a range of approaches to policy development, service delivery issues, and management practices. A horizontal initiative may take place across levels of government, across boundaries between units of a single department or agency or among multiple departments or agencies, or across public,…

  4. New solutions for the confined horizontal aquifer

    NASA Astrophysics Data System (ADS)

    Akylas, Evangelos; Gravanis, Elias

    2016-04-01

    The Boussinesq equation is a dynamical equation for the free surface of saturated subsurface flows over an impervious bed. Boussinesq equation is non-linear. The non-linearity comes from the reduction of the dimensionality of the problem: The flow is assumed to be vertically homogeneous, therefore the flow rate through a cross section of the flow is proportional to the free surface height times the hydraulic gradient, which is assumed to be equal to the slope of the free surface. In the present work we consider the case of the subsurface flow with horizontal bed. This is a case with an infinite Henderson and Wooding parameter, that is, it is the limiting case where the non-linear term is present in the Boussinesq equation while the linear spatial derivative term vanishes. Nonetheless, no analogue of the kinematic wave exists in this case as there is no exact solution for the build-up phase. Neither is there an exact recession-phase solution that holds in early times, as the Boussinesq separable solution is actually an asymptotic solution for large times. We construct approximate solutions for the horizontal aquifer which utilize directly the dynamical content of the non-linear Boussinesq equation. The approximate character of the solution lies in the fact that we start with a pre-supposed form for the solution, an educated guess, based on the nature of the initial condition as well as empirical observations from the numerical solution of the problem. The forms we shall use are power series of the location variable x along the bed with time-dependent coefficients. The series are not necessarily analytic. The boundary conditions are incorporated in the structure of the series from the beginning. The time-dependent coefficients are then determined by applying the Boussinesq equation and its spatial derivatives at the end-points of the aquifer. The forms are chosen also on the basis of their solubility; we would like to be able to construct explicitly the approximate

  5. Behavior of tetracycline and sulfamethazine with corresponding resistance genes from swine wastewater in pilot-scale constructed wetlands.

    PubMed

    Liu, Lin; Liu, Yu-Hong; Wang, Zhen; Liu, Chao-Xiang; Huang, Xu; Zhu, Ge-Fu

    2014-08-15

    Four pilot-scale constructed wetlands (free water surface, SF; horizontal subsurface flow, HSF; vertical subsurface flows with different water level, VSF-L and VSF-H) were operated to assess their ability to remove sulfamethazine (SMZ) and tetracycline (TC) from wastewaters, and to investigate the abundance level of corresponding resistance genes (sulI, sulII, tetM, tetW and tetO) in the CWs. The results indicated that CWs could significantly reduce the concentration of antibiotics in wastewater, and the mass removal rate range of SMZ and TC were respectively 11%-95% and 85%-95% in the four systems on the basis of hydraulic equilibrium; further relatively high removal rate was observed in VSF with low water level. Seasonal condition had a significant effect on SMZ removal in the CWs (especially SMZ in SF), but TC removal in VSFs were not considered to have statistically significant differences in winter and summer. At the end period, the relative abundances of target genes in the CWs showed obvious increases compared to initial levels, ranging from 2.98 × 10(-5) to 1.27 × 10(-1) for sul genes and 4.68 × 10(-6) to 1.54 × 10(-1) for tet genes after treatment, and those abundances showed close relation to both characteristic of wastewater and configuration of CWs.

  6. SUBSURFACE VISUAL ALARM SYSTEM ANALYSIS

    SciTech Connect

    D.W. Markman

    2001-08-06

    The ''Subsurface Fire Hazard Analysis'' (CRWMS M&O 1998, page 61), and the document, ''Title III Evaluation Report for the Surface and Subsurface Communication System'', (CRWMS M&O 1999a, pages 21 and 23), both indicate the installed communication system is adequate to support Exploratory Studies Facility (ESF) activities with the exception of the mine phone system for emergency notification purposes. They recommend the installation of a visual alarm system to supplement the page/party phone system The purpose of this analysis is to identify data communication highway design approaches, and provide justification for the selected or recommended alternatives for the data communication of the subsurface visual alarm system. This analysis is being prepared to document a basis for the design selection of the data communication method. This analysis will briefly describe existing data or voice communication or monitoring systems within the ESF, and look at how these may be revised or adapted to support the needed data highway of the subsurface visual alarm. system. The existing PLC communication system installed in subsurface is providing data communication for alcove No.5 ventilation fans, south portal ventilation fans, bulkhead doors and generator monitoring system. It is given that the data communication of the subsurface visual alarm system will be a digital based system. It is also given that it is most feasible to take advantage of existing systems and equipment and not consider an entirely new data communication system design and installation. The scope and primary objectives of this analysis are to: (1) Briefly review and describe existing available data communication highways or systems within the ESF. (2) Examine technical characteristics of an existing system to disqualify a design alternative is paramount in minimizing the number of and depth of a system review. (3) Apply general engineering design practices or criteria such as relative cost, and degree of

  7. Feasibility of electrokinetic soil remediation in horizontal Lasagna cells.

    PubMed

    Roulier, M; Kemper, M; Al-Abed, S; Murdoch, L; Cluxton, P; Chen, J; Davis-Hoover, W

    2000-10-02

    An integrated soil remediation technology called Lasagna has been developed that combines electrokinetics with treatment zones for use in low permeability soils where the rates of hydraulic and electrokinetic transport are too low to be useful for remediation of contaminants. The technology was developed by two groups, one involving industrial partners and the DOE and another involving US EPA and the University of Cincinnati, who pursued different electrode geometries. The Industry/DOE group has demonstrated the technology using electrodes and treatment zones installed vertically from the soil surface. We have demonstrated the feasibility of installing horizontal electrodes and treatment zones in subsurface soils by hydraulic fracturing, a process that we adapted from petroleum industry practices. When horizontal electrodes were connected to a dc power supply, uniform electrical potential gradients of 10-40 V/m were created in soil between the electrodes, inducing electroosmotic flow that facilitated movement of water and contaminants into treatment zones between the electrodes.

  8. Subsurface damage from oblique impacts into low-impedance layers

    NASA Astrophysics Data System (ADS)

    Stickle, A. M.; Schultz, P. H.

    2012-07-01

    Layered planetary surfaces occur ubiquitously in the solar system, where sedimentary sequences or icy layers overlay crystalline bedrock. Previous experimental studies investigated how the presence of weak layer overlying a strong basement affects crater morphology, subsurface damage and soft-sediment compression. Numerical studies generally focus on the final morphology as a function of thicknesses and burial depths of weak layers. In field studies of impact craters, the shock state of minerals is a key metric. Here, we evaluate the effect of a surficial low-impedance layer on peak pressure magnitudes and consequent damage extent in the competent substrate. Laboratory experiments coupled with 3D CTH models of oblique (30° from horizontal) hypervelocity impacts at laboratory and planetary scales show that surface layers with a thickness on the order of the projectile diameter shield the underlying surface and absorb/scatter ˜70% of the impact energy. Numerical simulations reveal that surficial layers reduce peak pressure magnitudes within the subsurface by ˜60-70%, while damage in the substrate is due to shear failure. Sedimentary layers are more efficient shields than icy layers, but both reduce the extent of subsurface damage and the resulting shock levels recorded by minerals. These results indicate that a thin surficial low impedance layer mitigates the expression of shocked minerals in the substrate even when a structural response is still observed.

  9. Subsurface Electromagnetic Target Characterization and Identification

    DTIC Science & Technology

    1979-06-01

    B. Subsurface Electromagnetic Video Pulse Radar System 5 C. The Subsurface Targets 11 D. Raw Measured Waveforms 14 E. Processed Waveforms 15 III...259 r i. I .. . . .... .. . . . . .;. . . . .. .. o _ • v . . • • • -• -. . .. -"... .. . II II LIST OF FIGURES Figure Page 1 The subsurface pulse ...7 3 Typical raw waveform received by the pulse radar system ..... ................... .i..... 9 4 Physical characteristics of the subsurface

  10. Vertical and horizontal distributions of coral-reef fish larvae in open water immediately prior to reef colonization.

    PubMed

    Lecchini, D; Waqalevu, V P; Holles, S; Lerohellec, M; Brie, C; Simpson, S D

    2013-06-01

    To explore the vertical and horizontal distributions of fish larvae near the end of their pelagic period, six light traps were set up over four lunar months at different depths (sub-surface, midwater and bottom) and different habitat types (reef slope: 50 m horizontal distance from the reef crest; frontier zone: 110 m horizontal distance; sandy zone: 200 m horizontal distance) on the outer reef slope of Moorea Island, French Polynesia. The highest captures were in sub-surface traps on the reef slope and the frontier zone, and in bottom traps on the sandy zone and the frontier zone. It is hypothesized that fish larvae move towards the surface near the reef slope to avoid reef-based planktivores and to get into a favourable position for surfing over the reef crest.

  11. Method of installing subsurface barrier

    SciTech Connect

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-10-09

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  12. INL Subsurface Wireless Sensor Platform

    SciTech Connect

    Dennis C. Kunerth; John M. Svoboda; James T. Johnson

    2005-10-01

    The Idaho National Laboratory is developing a versatile micro-power sensor interface platform for periodic subsurface sensing of environmental variables important to waste disposal sites such as volumetric moisture, water potential, and temperature. The key characteristics of the platform architecture are that the platform is passive until externally energized --no internal power source is required -- and that it communicates with a "reader" via short-range telemetry - no wires penetrate the subsurface. Other significant attributes include the potential for a long service life and a compact size that makes it well suited for retrofitting existing landfill structures. Functionally, the sensor package is "read" by a short-range induction coil that activates and powers the sensor platform as well as detects the sensor output via a radio frequency signal generated by the onboard programmable interface controller microchip. As a result, the platform has a functional subsurface communication range of approximately 10 to 12 ft. and can only accept sensors that require low power to operate.

  13. Analysis of riverbed temperatures to determine the geometry of subsurface water flow around in-stream geomorphological structures

    NASA Astrophysics Data System (ADS)

    Munz, Matthias; Oswald, Sascha E.; Schmidt, Christian

    2016-08-01

    The analytical evaluation of diurnal temperature variation in riverbed sediments provides detailed information on exchange fluxes between rivers and groundwater. The underlying assumption of the stationary, one-dimensional vertical flow field is frequently violated in natural systems where subsurface water flow often has a significant horizontal component. In this paper, we present a new methodology for identifying the geometry of the subsurface flow field using vertical temperature profiles. The statistical analyses are based on model optimisation and selection and are used to evaluate the shape of vertical amplitude ratio profiles. The method was applied to multiple profiles measured around in-stream geomorphological structures in a losing reach of a gravel bed river. The predominant subsurface flow field was systematically categorised in purely vertical and horizontal (hyporheic, parafluvial) components. The results highlight that river groundwater exchange flux at the head, crest and tail of geomorphological structures significantly deviated from the one-dimensional vertical flow, due to a significant horizontal component. The geometry of the subsurface water flow depended on the position around the geomorphological structures and on the river level. The methodology presented in this paper features great potential for characterising the spatial patterns and temporal dynamics of complex subsurface flow geometries by using measured temperature time series in vertical profiles.

  14. X-15 pilots

    NASA Technical Reports Server (NTRS)

    1965-01-01

    X-15 Pilots, Left to Right: Air Force pilot William J. 'Pete' Knight, Air Force Major Robert A. Rushworth, Air Force Captain Joseph H. Engle, NASA pilot Milton O. Thompson, NASA pilot Bill Dana, and NASA pilot John B. 'Jack' McKay.

  15. On the dynamical mechanisms explaining the western Pacific subsurface temperature buildup leading to ENSO events

    NASA Astrophysics Data System (ADS)

    Ballester, Joan; Bordoni, Simona; Petrova, Desislava; Rodó, Xavier

    2015-04-01

    Despite steady progress in the understanding of El Niño-Southern Oscillation (ENSO) in the past decades, questions remain on the exact mechanisms explaining the heat buildup leading to the onset of El Niño (EN) events. Here we use an ensemble of ocean and atmosphere assimilation products to identify mechanisms that are consistently identified by all the data sets and that contribute to the heat buildup in the western Pacific 18 to 24 months before the onset of EN events. Meridional and eastward heat advection due to equatorward subsurface mass convergence and transport along the equatorial undercurrent are found to contribute to the subsurface warming at 170°E-150°W. In the warm pool, instead, surface horizontal convergence and downwelling motion have a leading role in subsurface warming. The picture emerging from our results highlights a sharp dynamical transition at 170°E near the level of the thermocline.

  16. Using lunar sounder imagery to distinguish surface from subsurface reflectors in lunar highlands areas

    NASA Technical Reports Server (NTRS)

    Cooper, Bonnie L.; Carter, James L.

    1993-01-01

    We have developed a method using the Apollo 17 Lunar Sounder imagery data which appears capable of filtering out off-nadir surface noise from highland area profiles, so that subsurface features may now be detected in highland areas as well as mare areas. Previously, this had been impossible because the rough topography in the highland areas created noise in the profiles which could not be distinguished from subsurface echoes. The new method is an image processing procedure involving the computerized selection of pixels which represent intermediate echo intensity values, then manually removing those pixels from the profile. Using this technique, a subsurface feature with a horizontal extent of about 150 km, at a calculated depth of approximately 3 km, has been detected beneath the crater Riccioli in the highlands near Oceanus Procellarum. This result shows that the ALSE data contain much useful information that remains to be extracted and used.

  17. Nuclear component horizontal seismic restraint

    DOEpatents

    Snyder, Glenn J.

    1988-01-01

    A nuclear component horizontal seismic restraint. Small gaps limit horizontal displacement of components during a seismic occurrence and therefore reduce dynamic loadings on the free lower end. The reactor vessel and reactor guard vessel use thicker section roll-forged rings welded between the vessel straight shell sections and the bottom hemispherical head sections. The inside of the reactor guard vessel ring forging contains local vertical dovetail slots and upper ledge pockets to mount and retain field fitted and installed blocks. As an option, the horizontal displacement of the reactor vessel core support cone can be limited by including shop fitted/installed local blocks in opposing alignment with the reactor vessel forged ring. Beams embedded in the wall of the reactor building protrude into apertures in the thermal insulation shell adjacent the reactor guard vessel ring and have motion limit blocks attached thereto to provide to a predetermined clearance between the blocks and reactor guard vessel ring.

  18. Applicability of petroleum horizontal drilling technology to hazardous waste site characterization and remediation

    SciTech Connect

    Goranson, C.

    1992-09-01

    Horizontal wells have the potential to become an important tool for use in characterization, remediation and monitoring operations at hazardous waste disposal, chemical manufacturing, refining and other sites where subsurface pollution may develop from operations or spills. Subsurface pollution of groundwater aquifers can occur at these sites by leakage of surface disposal ponds, surface storage tanks, underground storage tanks (UST), subsurface pipelines or leakage from surface operations. Characterization and remediation of aquifers at or near these sites requires drilling operations that are typically shallow, less than 500-feet in depth. Due to the shallow nature of polluted aquifers, waste site subsurface geologic formations frequently consist of unconsolidated materials. Fractured, jointed and/or layered high compressive strength formations or compacted caliche type formations can also be encountered. Some formations are unsaturated and have pore spaces that are only partially filled with water. Completely saturated underpressured aquifers may be encountered in areas where the static ground water levels are well below the ground surface. Each of these subsurface conditions can complicate the drilling and completion of wells needed for monitoring, characterization and remediation activities. This report describes some of the equipment that is available from petroleum drilling operations that has direct application to groundwater characterization and remediation activities. A brief discussion of petroleum directional and horizontal well drilling methodologies is given to allow the reader to gain an understanding of the equipment needed to drill and complete horizontal wells. Equipment used in river crossing drilling technology is also discussed. The final portion of this report is a description of the drilling equipment available and how it can be applied to groundwater characterization and remediation activities.

  19. Speckle Imaging Over Horizontal Paths

    SciTech Connect

    Carrano, C J

    2002-05-21

    Atmospheric aberrations reduce the resolution and contrast in surveillance images recorded over horizontal or slant paths. This paper describes our recent horizontal and slant path imaging experiments of extended scenes as well as the results obtained using speckle imaging. The experiments were performed with an 8-inch diameter telescope placed on either a rooftop or hillside and cover ranges of interest from 0.5 km up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures. The improvement in image quality using speckle imaging is dramatic in many cases, and depends significantly upon the atmospheric conditions. We quantify resolution improvement through modulation transfer function measurement comparisons.

  20. Introduction: energy and the subsurface.

    PubMed

    Christov, Ivan C; Viswanathan, Hari S

    2016-10-13

    This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO2) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection.This article is part of the themed issue 'Energy and the subsurface'.

  1. Phylogenetic relationships among subsurface microorganisms

    SciTech Connect

    Nierzwicki-Bauer, S.A.

    1991-01-01

    This project involves the development of group specific 16S ribosomal RNA-targeted oligonucleotide hybridization probes for the rapid detection of specific types of subsurface organisms (e.g., groups of microbes that share certain physiological traits). Major accomplishments for the period of 6/91 to 12/1/91 are described. Nine new probes have been synthesized on the basis of published 16S rRNA sequence data from the Ribosomal Database Project. We have initiated rapid screening of many of the subsurface microbial isolates obtained from the P24 borehole at the Savannah River Site. To date, we have screened approximately 50% of the isolates from P24. We have optimized our {und in situ} hybridization technique, and have developed a cell blot hybridization technique to screen 96 samples on a single blot. This is much faster than reading 96 individual slides. Preliminary experiments have been carried out which indicate specific nutrients can be used to amplify rRNA only in those organisms capable of metabolizing those nutrients. 1 tab., 2 figs.

  2. Invertebrates associated with a horizontal-flow, subsurface constructed wetland in a northern climate.

    PubMed

    Giordano, Rosanna; Weber, Everett; Darby, Brian J; Soto-Adames, Felipe N; Murray, Robert E; Drizo, Aleksandra

    2014-04-01

    Wetlands function as buffers between terrestrial and aquatic ecosystems, filtering pollutants generated by human activity. Constructed wetlands were developed to mimic the physical and biological filtering functions of natural systems for the treatment of human and animal waste under controlled conditions. Previous studies on the effect of constructed wetlands on native invertebrate populations have concentrated almost exclusively on mosquitoes. Here, we present the first study investigating the relationship between vegetation cover and aeration regime, and the diversity and abundance of nematodes and springtails (Collembola) in a constructed wetland designed to treat dairy farm wastewater in northwestern Vermont. We investigated four treatment cells differing in aeration regime and vegetation cover, but equally overlaid by a layer of compost to provide insulation. Analysis showed that nematodes were most abundant in the nonplanted and nonaerated cells, and that bacterivorous nematodes dominated the community in all cells. Springtails were found to be most numerous in the planted and nonaerated cells. We hypothesize that the vegetation provided differing environmental niches that supported a more diverse system of bacteria and fungi, as well as offering protection from predators and inclement weather. Nematodes were likely imported with the original compost material, while springtails migrated into the cells either via air, water, or direct locomotion.

  3. Horizontal electric fields from lightning return strokes

    NASA Technical Reports Server (NTRS)

    Thomson, E. M.; Medelius, P. J.; Rubinstein, M.; Uman, M. A.; Johnson, J.

    1988-01-01

    An experiment to measure simultaneously the wideband horizontal and vertical electric fields from lightning return strokes is described. Typical wave shapes of the measured horizontal and vertical fields are presented, and the horizontal fields are characterized. The measured horizontal fields are compared with calculated horizontal fields obtained by applying the wavetilt formula to the vertical fields. The limitations and sources of error in the measurement technique are discussed.

  4. Horizontal drilling installs dutch waterline

    SciTech Connect

    Not Available

    1986-08-01

    A 32-in. potable water line system, installed by Van Eijk Leidingen B.V. in Holland, was laid through an intensively cultivated vegetable gardening area, and designed to furnish additional irrigation water. Using a horizontally drilled 42-in. hole under the Maasdijk, though a difficult job, reduced the length by more than 3 miles.

  5. Performance of pilot-scale constructed wetlands for secondary treatment of chromium-bearing tannery wastewaters.

    PubMed

    Dotro, Gabriela; Castro, Silvana; Tujchneider, Ofelia; Piovano, Nancy; Paris, Marta; Faggi, Ana; Palazolo, Paul; Larsen, Daniel; Fitch, Mark

    2012-11-15

    Tannery operations consist of converting raw animal skins into leather through a series of complex water- and chemically-intensive batch processes. Even when conventional primary treatment is supplemented with chemicals, the wastewater requires some form of biological treatment to enable the safe disposal to the natural environment. Thus, there is a need for the adoption of low cost, reliable, and easy-to-operate alternative secondary treatment processes. This paper reports the findings of two pilot-scale wetlands for the secondary treatment of primary effluents from a full tannery operation in terms of resilience (i.e., ability to produce consistent effluent quality in spite of variable influent loads) and reliability (i.e., ability to cope with sporadic shock loads) when treating this hazardous effluent. Areal mass removal rates of 77.1 g COD/m2/d, 11 g TSS/m2/d, and 53 mg Cr/m2/d were achieved with a simple gravity-flow horizontal subsurface flow unit operating at hydraulic loading rates of as much as 10 cm/d. Based on the findings, a full-scale wetland was sized to treat all the effluent from the tannery requiring 68% more land than would have been assumed based on literature values. Constructed wetlands can offer treatment plant resilience for minimum operational input and reliable effluent quality when biologically treating primary effluents from tannery operations.

  6. History and anatomy of subsurface ice on Mars

    NASA Astrophysics Data System (ADS)

    Schorghofer, Norbert; Forget, Francois

    2012-08-01

    Ice buried beneath a thin layer of soil has been revealed by neutron spectroscopy and explored by the Phoenix Mars Lander. It has also been exposed by recent impacts. This subsurface ice is thought to lose and gain volume in response to orbital variations (Milankovitch cycles). We use a powerful numerical model to follow the growth and retreat of near-surface ice as a result of regolith-atmosphere exchange continuously over millions of years. If a thick layer of almost pure ice has been deposited recently, it has not yet reached equilibrium with the atmospheric water vapor and may still remain as far equatorward as 43°N, where ice has been revealed by recent impacts. A potentially observable consequence is present-day humidity output from the still retreating ice. We also demonstrate that in a sublimation environment, subsurface pore ice can accumulate in two ways. The first mode, widely known, is the progressive filling of pores by ice over a range of depths. The second mode occurs on top of an already impermeable ice layer; subsequent ice accumulates in the form of pasted on horizontal layers such that beneath the ice table, the pores are completely full with ice. Most or all of the pore ice on Mars today may be of the second type. At the Phoenix landing site, where such a layer is also expected to exist above an underlying ice sheet, it may be extremely thin, due to exceptionally small variations in ice stability over time.

  7. Design and performance of a horizontal mooring for upper-ocean research

    USGS Publications Warehouse

    Grosenbaugh, Mark; Anderson, Steven; Trask, Richard; Gobat, Jason; Paul, Walter; Butman, Bradford; Weller, Robert

    2002-01-01

    This paper describes the design and performance of a two-dimensional moored array for sampling horizontal variability in the upper ocean. The mooring was deployed in Massachusetts Bay in a water depth of 84 m for the purpose of measuring the horizontal structure of internal waves. The mooring was instrumented with three acoustic current meters (ACMs) spaced along a 170-m horizontal cable that was stretched between two subsurface buoys 20 m below the sea surface. Five 25-m-long vertical instrument strings were suspended from the horizontal cable. A bottom-mounted acoustic Doppler current profiler (ADCP) was deployed nearby to measure the current velocity throughout the water column. Pressure sensors mounted on the subsurface buoys and the vertical instrument strings were used to measure the vertical displacements of the array in response to the currents. Measurements from the ACMs and the ADCP were used to construct time-dependent, two-dimensional current fields. The current fields were used as input to a numerical model that calculated the deformation of the array with respect to the nominal zero-current configuration. Comparison of the calculated vertical offsets of the downstream subsurface buoy and downstream vertical instrument string with the pressure measurements were used to verify the numerical code. These results were then used to estimate total deformation of the array due to the passage of the internal waves. Based on the analysis of the three internal wave events with the highest measured vertical offsets, it is concluded that the geometry of the main structure (horizontal cable and anchor legs) was kept to within ±2.0 m, and the geometry of the vertical instrument strings was kept to within ±4.0 m except for one instance when the current velocity reached 0.88 m s−1.

  8. The integration of control and display concepts for improved pilot situational awareness

    NASA Technical Reports Server (NTRS)

    Person, L. H., Jr.; Steinmetz, G. G.

    1981-01-01

    Consideration is given to a part of the Langley Terminal Configured Vehicle program in which the pilot is retained as an active segment of an integrated system. The pilot is active in the outer control loop and controls the orientation of the aircraft velocity. The pilot thus has a task, but a low workload. Attention is also given to first- and second-generation primary flight display for horizontal and vertical situation awareness.

  9. Microbial processes and subsurface contaminants

    NASA Astrophysics Data System (ADS)

    Molz, Fred J.

    A Chapman Conference entitled “Microbial Processes in the Transport, Fate, and In Situ Treatment of Subsurface Contaminants” was held in Snowbird, Utah, October 1-3, 1986. Members of the program committee and session chairmen were Lenore Clesceri (Rensselaer Polytechnic Institute, Troy, N.Y.), David Gibson (University of Texas, Austin), James Mercer (GeoTrans, Inc., Herndon , Va.), Donald Michelsen (Virginia Polytechnic Institute and State University, Blacksburg), Fred Molz (Auburn University, Auburn, Ala.), Bruce Rittman (University of Illinois, Urbana), Gary Sayler (University of Tennessee, Knoxville), and John T. Wilson (U.S. Environmental Protection Agency, Ada, Okla.). The following report attempts to highlight the six sessions that constituted the conference. For additional information, including a bound summary and abstracts, contact Fred J. Molz, Civil Engineering Department, Auburn University, AL 36849 (telephone: 205-826-4321).

  10. Chromium removal from wastewater using HSF and VF pilot-scale constructed wetlands: Overall performance, and fate and distribution of this element within the wetland environment.

    PubMed

    Papaevangelou, Vassiliki A; Gikas, Georgios D; Tsihrintzis, Vassilios A

    2017-02-01

    The current experimental work aimed at the investigation of the overall chromium removal capacity of constructed wetlands (CWs) and the chromium fate-distribution within a wetland environment. For this purpose, the experimental setup included the parallel operation and monitoring of two horizontal subsurface flow (HSF) pilot-scale CWs and two vertical flow (VF) pilot-scale CWs treating Cr-bearing wastewater. Samples were collected from the influent, the effluent, the substrate and the plants. Apart from the continuous experiment, batch experiments (kinetics and isotherm) were conducted in order to investigate the chromium adsorption capacity of the substrate material. According to the findings, HSF-CWs demonstrated higher removal capacities in comparison to VF-CWs, while in both types the planted units indicated better performance compared to the unplanted ones. Analysis in various wetland compartments and annual mass balance calculation highlighted the exceptional contribution of substrate to chromium retention, while Cr accumulation in plant was not so high. Finally, experimental data fitted better to the pseudo-second-order and Langmuir models regarding kinetics and isotherm simulation.

  11. Strategies for Reforming Initial Vocational Education and Training in Europe. Final Report of the Project. Leonardo da Vinci/Transnational Pilot Projects: Multiplier Effect, Strand III.3.a. Sharpening Post-16 Education Strategies by Horizontal and Vertical Networking (1997-2000).

    ERIC Educational Resources Information Center

    Stenstrom, Marja-Leena, Ed.; Lasonen, Johanna, Ed.

    This document contains 24 papers examining strategies for reforming initial vocational education and training (VET) in Europe. The following papers are included: "Reassessing VET Reform Strategies in a New Context: Implementation of the SPES-NET (Sharpening Post-16 Education Strategies by Horizontal and Vertical Networking) Project"…

  12. Horizontal-branch stellar evolution

    NASA Technical Reports Server (NTRS)

    Sweigart, Allen V.

    1990-01-01

    The results of canonical theory for the evolution of horizontal-branch (HB) stars are examined. Particular attention is given to how an HB star maintains the appropriate composition distribution within the semiconvective zone and how this composition is affected by the finite time-dependence with which convective boundaries actually move. Newly developed models based on time-dependent overshooting are presented for both the core-helium-exhaustion and main HB phases.

  13. Rock characterization in reservoirs targeted for horizontal drilling

    SciTech Connect

    Skopec, R.A. )

    1993-12-01

    Achieving the maximum economic benefit from horizontal drilling requires thorough understanding of reservoir characteristics. The direct measurement of rock properties from oriented core is critical in horizontal-wellbore design. This paper outlines the measures and testing necessary to evaluate naturally fractured reservoirs effectively with field and laboratory technologies. Rock mechanical properties, fracture strike, and principal in-situ stress magnitudes and directions should be known before a horizontal wellbore is drilled. These data can then be used to maximize the intersection of natural fractures and to minimize the potential of borehole failure. In exploration wells, a vertical pilot hole must first be drilled. The zone of interest is cored, field tests are performed, laboratory testing is completed, and the reservoir is evaluated. With this information available, decisions can be made to optimize the borehole azimuth and well placement. The authors have used this approach to formation evaluation in several reservoirs where rock characterization is essential in the exploration and drilling program. 72 refs., 10 figs.

  14. Industry survey for horizontal wells. Final report

    SciTech Connect

    Wilson, D.D.; Kaback, D.S.; Denhan, M.E.; Watkins, D.

    1993-07-01

    An international survey of horizontal environmental wells was performed during May and June of 1993. The purpose of the survey was to provide the environmental industry with an inventory of horizontal environmental wells and information pertaining to the extent of the use of horizontal environmental wells, the variety of horizontal environmental well applications, the types of geologic and hydrogeologic conditions within which horizontal environmental wells have been installed, and the companies that perform horizontal environmental well installations. Other information, such as the cost of horizontal environmental well installations and the results of tests performed on the wells, is not complete but is provided as general information with the caveat that the information should not be used to compare drilling companies. The result of the survey is a catalogue of horizontal environmental wells that are categorized by the objective or use of the wells, the vertical depth of the wells, and the drilling company contracted to install the wells.

  15. Introduction: energy and the subsurface

    PubMed Central

    Viswanathan, Hari S.

    2016-01-01

    This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO2) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection. This article is part of the themed issue ‘Energy and the subsurface’. PMID:27597784

  16. Fluid-powered subsurface pump

    SciTech Connect

    Gipson, T.C.

    1991-12-03

    This paper describes a fluid-powered pump for attachment to small diametered coiled tubing for pumping subsurface liquid from a well production tube. It comprises: a pump housing having an upper end and a lower end, the upper end releasably attachable to a downhole end of the coiled tubing, the inside of the upper end of the housing in fluid communication with the inside of the coiled tubing; a cross head seal member dividing the pump into an upper chamber and a lower chamber, the upper chamber in fluid communication with the inside of the coiled tubing; a pump actuator extending between the upper and lower chambers, the actuator having an upper piston head sealingly fitted to reciprocate in the upper chamber and a lower piston head sealingly fitted to reciprocate in the lower chamber, the upper piston head and the lower piston head connected to each other by a connector rod sealing slidable in the cross head seal member, the actuator having a conduit for fluid communication between the upper chamber and the lower chamber, the conduit extending from an orifice in the top surface of the upper piston head, through the connector rod to a port above the top surface of the lower piston head.

  17. Subsurface Explosions in Granular Media

    NASA Astrophysics Data System (ADS)

    Lai, Shuyue; Houim, Ryan; Oran, Elaine

    2015-11-01

    Numerical simulations of coupled gas-granular flows are used to study properties of shock formation and propagation in media, such as sand or regolith on the moon, asteroids, or comets. The simulations were performed with a multidimensional fully compressible model, GRAF, which solves two sets of coupled Navier-Stokes equations, one for the gas and one for the granular medium. The specific case discussed here is for a subsurface explosion in a granular medium initiated by an equivalent of 200g of TNT in depths ranging from 0.1m to 3m. The background conditions of 100K, 10 Pa and loose initial particle volume fraction of 25% are consistent with an event on a comet. The initial blast creates a cavity as a granular shock expands outwards. Since the gas-phase shock propagates faster than the granular shock in loose, granular material, some gas and particles are ejected before the granular shock arrives. When the granular shock reaches the surface, a cap-like structure forms. This cap breaks and may fall back on the surface and in this process, relatively dense particle clusters form. At lower temperatures, the explosion timescales are increased and entrained particles are more densely packed.

  18. Portable Horizontal-Drilling And Positioning Device

    NASA Technical Reports Server (NTRS)

    Smigocki, Edmund; Johnson, Clarence

    1988-01-01

    Portable horizontal-drilling and positioning device, constructed mainly of off-the-shelf components, accurately drills horizontal small holes in irregularly shaped objects. Holes precisely placed and drilled in objects that cannot be moved to shop area. New device provides three axes of movement while maintaining horizontal drilling.

  19. Panspermia and horizontal gene transfer

    NASA Astrophysics Data System (ADS)

    Klyce, Brig

    2009-08-01

    Evidence that extremophiles are hardy and ubiquitous is helping to make panspermia a respectable theory. But even if life on Earth originally came from space, biologists assume that the subsequent evolution of life is still governed by the darwinian paradigm. In this review we show how panspermia could amend darwinism and point to a cosmic source for, not only extremophiles but, all of life. This version of panspermia can be called "strong panspermia." To support this theory we will discuss recent evidence pertaining to horizontal gene transfer, viruses, genes apparently older than the Earthly evolution of the features they encode, and primate-specific genes without identifiable precursors.

  20. Subsurface application enhances benefits of manure redistribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable nutrient management requires redistribution of livestock manure from nutrient-excess areas to nutrient-deficit areas. Field experiments were conducted to assess agronomic and environmental effects of different poultry litter application methods (surface vs. subsurface) and timings (fall ...

  1. Subsurface Imaging with the Scanning Microwave Microscope

    NASA Astrophysics Data System (ADS)

    Kopanski, Joseph; You, Lin; Michelson, Jonathan; Hitz, Emily; Obeng, Yaw; Back End of the Line Reliability; Metrology Project Team

    2015-03-01

    The scanning microwave microscope (SMM) forms images from the reflected amplitude and phase of an incident RF (~ 2.3 GHz) signal. The reflected signal is a function of the properties of the tip-sample contact, but can also be influenced by buried interfaces and subsurface variations of the sample permittivity. This mechanism allows limited imaging of conductors buried within dielectrics, voids within metal, or multiple metal layers with different permittivity. Subsurface SMM data acquisition modes include passive and various active data acquisition modes. The theory of sub-surface imaging with SMM and COMSOL multi-physics simulations of specific situations will be presented. Measurements of specifically designed test structures and correlation with simulations show the sensitivity and resolution of the technique applied to imaging subsurface metal lines embedded in dielectric. Applications include metrology for back end of the line (BEOL) multi-level metallization and three-dimensional integrated circuits (3D-ICs).

  2. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    SciTech Connect

    D.C. Randle

    2000-01-07

    The primary purpose of this document is to develop a preliminary high-level functional and physical control system architecture for the potential repository at Yucca Mountain. This document outlines an overall control system concept that encompasses and integrates the many diverse process and communication systems being developed for the subsurface repository design. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The Subsurface Repository Integrated Control System design will be composed of a series of diverse process systems and communication networks. The subsurface repository design contains many systems related to instrumentation and control (I&C) for both repository development and waste emplacement operations. These systems include waste emplacement, waste retrieval, ventilation, radiological and air monitoring, rail transportation, construction development, utility systems (electrical, lighting, water, compressed air, etc.), fire protection, backfill emplacement, and performance confirmation. Each of these systems involves some level of I&C and will typically be integrated over a data communications network throughout the subsurface facility. The subsurface I&C systems will also interface with multiple surface-based systems such as site operations, rail transportation, security and safeguards, and electrical/piped utilities. In addition to the I&C systems, the subsurface repository design also contains systems related to voice and video communications. The components for each of these systems will be distributed and linked over voice and video communication networks throughout the subsurface facility. The scope and primary objectives of this design analysis are to: (1) Identify preliminary system-level functions and interfaces (Section 6.2). (2) Examine the overall system complexity and determine how and on what levels the engineered process systems will be monitored, controlled, and

  3. Microbial life in the deep terrestrial subsurface

    SciTech Connect

    Fliermans, C.B.; Balkwill, D.L.; Beeman, R.E.

    1988-12-31

    The distribution and function of microorganisms is a vital issue in microbial ecology. The US Department of Energy`s Program, ``Microbiology of the Deep Subsurface,`` concentrates on establishing fundamental scientific information about organisms at depth, and the use of these organisms for remediation of contaminants in deep vadose zone and groundwater environments. This investigation effectively extends the Biosphere hundreds of meters into the Geosphere and has implications to a variety of subsurface activities.

  4. Floating insulated conductors for heating subsurface formations

    DOEpatents

    Burns, David; Goodwin, Charles R.

    2014-07-29

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  5. Immunological techniques as tools to characterize the subsurface microbial community at a trichloroethylene contaminated site

    SciTech Connect

    Fliermans, C.B.; Dougherty, J.M.; Franck, M.M.; McKinzey, P.C.; Hazen, T.C.

    1992-01-01

    Effective in situ bioremediation strategies require an understanding of the effects pollutants and remediation techniques have on subsurface microbial communities. Therefore, detailed characterization of a site's microbial communities is important. Subsurface sediment borings and water samples were collected from a trichloroethylene (TCE) contaminated site, before and after horizontal well in situ air stripping and bioventing, as well as during methane injection for stimulation of methane-utilizing microorganisms. Subsamples were processed for heterotrophic plate counts, acridine orange direct counts (AODC), community diversity, direct fluorescent antibodies (DFA) enumeration for several nitrogen-transforming bacteria, and Biolog [reg sign] evaluation of enzyme activity in collected water samples. Plate counts were higher in near-surface depths than in the vadose zone sediment samples. During the in situ air stripping and bioventing, counts increased at or near the saturated zone, remained elevated throughout the aquifer, but did not change significantly after the air stripping. Sporadic increases in plate counts at different depths as well as increased diversity appeared to be linked to differing lithologies. AODCs were orders of magnitude higher than plate counts and remained relatively constant with depth except for slight increases near the surface depths and the capillary fringe. Nitrogen-transforming bacteria, as measured by serospecific DFA, were greatly affected both by the in situ air stripping and the methane injection. Biolog[reg sign] activity appeared to increase with subsurface stimulation both by air and methane. The complexity of subsurface systems makes the use of selective monitoring tools imperative.

  6. Immunological techniques as tools to characterize the subsurface microbial community at a trichloroethylene contaminated site

    SciTech Connect

    Fliermans, C.B.; Dougherty, J.M.; Franck, M.M.; McKinzey, P.C.; Hazen, T.C.

    1992-12-31

    Effective in situ bioremediation strategies require an understanding of the effects pollutants and remediation techniques have on subsurface microbial communities. Therefore, detailed characterization of a site`s microbial communities is important. Subsurface sediment borings and water samples were collected from a trichloroethylene (TCE) contaminated site, before and after horizontal well in situ air stripping and bioventing, as well as during methane injection for stimulation of methane-utilizing microorganisms. Subsamples were processed for heterotrophic plate counts, acridine orange direct counts (AODC), community diversity, direct fluorescent antibodies (DFA) enumeration for several nitrogen-transforming bacteria, and Biolog {reg_sign} evaluation of enzyme activity in collected water samples. Plate counts were higher in near-surface depths than in the vadose zone sediment samples. During the in situ air stripping and bioventing, counts increased at or near the saturated zone, remained elevated throughout the aquifer, but did not change significantly after the air stripping. Sporadic increases in plate counts at different depths as well as increased diversity appeared to be linked to differing lithologies. AODCs were orders of magnitude higher than plate counts and remained relatively constant with depth except for slight increases near the surface depths and the capillary fringe. Nitrogen-transforming bacteria, as measured by serospecific DFA, were greatly affected both by the in situ air stripping and the methane injection. Biolog{reg_sign} activity appeared to increase with subsurface stimulation both by air and methane. The complexity of subsurface systems makes the use of selective monitoring tools imperative.

  7. Imaging lateral groundwater flow in the shallow subsurface using stochastic temperature fields

    NASA Astrophysics Data System (ADS)

    Fairley, Jerry P.; Nicholson, Kirsten N.

    2006-04-01

    Although temperature has often been used as an indication of vertical groundwater movement, its usefulness for identifying horizontal fluid flow has been limited by the difficulty of obtaining sufficient data to draw defensible conclusions. Here we use stochastic simulation to develop a high-resolution image of fluid temperatures in the shallow subsurface at Borax Lake, Oregon. The temperature field inferred from the geostatistical simulations clearly shows geothermal fluids discharging from a group of fault-controlled hydrothermal springs, moving laterally through the subsurface, and mixing with shallow subsurface flow originating from nearby Borax Lake. This interpretation of the data is supported by independent geochemical and isotopic evidence, which show a simple mixing trend between Borax Lake water and discharge from the thermal springs. It is generally agreed that stochastic simulation can be a useful tool for extracting information from complex and/or noisy data and, although not appropriate in all situations, geostatistical analysis may provide good definition of flow paths in the shallow subsurface. Although stochastic imaging techniques are well known in problems involving transport of species, e.g. delineation of contaminant plumes from soil gas survey data, we are unaware of previous applications to the transport of thermal energy for the purpose of inferring shallow groundwater flow.

  8. The Design and Implementation of Instruments for Low-Frequency Electromagnetic Sounding of the Martian Subsurface

    NASA Technical Reports Server (NTRS)

    Delory, G. T.; Grimm, R. E.

    2003-01-01

    Low-frequency electromagnetic soundings of the subsurface can identify liquid water at depths ranging from hundreds of meters to approx. 10 km in an environment such as Mars. Among the tools necessary to perform these soundings are low-frequency electric and magnetic field sensors capable of being deployed from a lander or rover such that horizontal and vertical components of the fields can be measured free of structural or electrical interference. Under a NASA Planetary Instrument Definition and Development Program (PIDDP), we are currently engaged in the prototype stages of low frequency sensor implementations that will enable this technique to be performed autonomously within the constraints of a lander platform. Once developed, this technique will represent both a complementary and alternative method to orbital radar sounding investigations, as the latter may not be able to identify subsurface water without significant ambiguities. Low frequency EM methods can play a crucial role as a ground truth measurement, performing deep soundings at sites identified as high priority areas by orbital radars. Alternatively, the penetration depth and conductivity discrimination of low-frequency methods may enable detection of subsurface water in areas that render radar methods ineffective. In either case, the sensitivity and depth of penetration inherent in low frequency EM exploration makes this tool a compelling candidate method to identify subsurface liquid water from a landed platform on Mars or other targets of interest.

  9. Delineation of the subsurface geological structures of Omu-Aran area, south-western Nigeria, using aeromagnetic data

    NASA Astrophysics Data System (ADS)

    Kayode, J. S.; Nawawi, M. N. M.; Baioumy, H. M.; Khalil, A. E.; Khiruddin, B. A.

    2015-04-01

    Omu-Aran area is characterized by mining activities to exploit the valuable mineralization there. These facts motivated the present work to evaluate the factors controlling the mineralization in the study area using aeromagnetic data obtained from the Nigerian Geological survey Agency. The data was processed and interpreted with the mean of delineating subsurface geological structures around Omu-Aran in Kwara State, South-western Nigeria. Data enhancement methods was performed on the aeromagnetic map using Regional Residual Separation of the total field anomalies map; horizontal gradient enhanced and International Geomagnetic Reference Field (IGRS) removed; reduced to the pole magnetic shaded relief image was carried out; Magnetic vertical gradient calculated, Magnetic horizontal gradient measured and Analytical signal map was constructed using some computer aided packages. The interpreted map enabled delineation of various subsurface geological structures such as the rock contacts, fractured and faulted areas.

  10. Formation dynamics of subsurface hydrocarbon intrusions following the Deepwater Horizon blowout

    USGS Publications Warehouse

    Socolofsky, S.A.; Adams, E.E.; Sherwood, C.R.

    2011-01-01

    Hydrocarbons released following the Deepwater Horizon (DH) blowout were found in deep, subsurface horizontal intrusions, yet there has been little discussion about how these intrusions formed. We have combined measured (or estimated) observations from the DH release with empirical relationships developed from previous lab experiments to identify the mechanisms responsible for intrusion formation and to characterize the DH plume. Results indicate that the intrusions originate from a stratification-dominated multiphase plume characterized by multiple subsurface intrusions containing dissolved gas and oil along with small droplets of liquid oil. Unlike earlier lab measurements, where the potential density in ambient water decreased linearly with elevation, at the DH site it varied quadratically. We have modified our method for estimating intrusion elevation under these conditions and the resulting estimates agree with observations that the majority of the hydrocarbons were found between 800 and 1200 m. Copyright ?? 2011 by the American Geophysical Union.

  11. Formation dynamics of subsurface hydrocarbon intrusions following the Deepwater Horizon blowout

    USGS Publications Warehouse

    Socolofsky, Scott A.; Adams, E. Eric; Sherwood, Christopher R.

    2011-01-01

    Hydrocarbons released following the Deepwater Horizon (DH) blowout were found in deep, subsurface horizontal intrusions, yet there has been little discussion about how these intrusions formed. We have combined measured (or estimated) observations from the DH release with empirical relationships developed from previous lab experiments to identify the mechanisms responsible for intrusion formation and to characterize the DH plume. Results indicate that the intrusions originate from a stratification-dominated multiphase plume characterized by multiple subsurface intrusions containing dissolved gas and oil along with small droplets of liquid oil. Unlike earlier lab measurements, where the potential density in ambient water decreased linearly with elevation, at the DH site it varied quadratically. We have modified our method for estimating intrusion elevation under these conditions and the resulting estimates agree with observations that the majority of the hydrocarbons were found between 800 and 1200 m.

  12. Feasibility of correlation mapping optical coherence tomography (cmOCT) for anti-spoof sub-surface fingerprinting.

    PubMed

    Zam, Azhar; Dsouza, Roshan; Subhash, Hrebesh M; O'Connell, Marie-Louise; Enfield, Joey; Larin, Kirill; Leahy, Martin J

    2013-09-01

    We propose the use of correlation mapping optical coherence tomography (cmOCT) to deliver additional biometrics associated with the finger that could complement existing fingerprint technology for law enforcement applications. The current study extends the existing fingerprint paradigm by measuring additional biometrics associated with sub-surface finger tissue such as sub-surface fingerprints, sweat glands, and the pattern of the capillary bed to yield a user-friendly cost effective and anti-spoof multi-mode biometric solution associated with the finger. To our knowledge no other method has been able to capture sub-surface fingerprint, papillary pattern and horizontal vessel pattern in a single scan or to show the correspondence between these patterns in live adult human fingertip. Unlike many current technologies this approach incorporates 'liveness' testing by default. The ultimate output is a biometric module which is difficult to defeat and complements fingerprint scanners that currently are used in border control and law enforcement applications.

  13. Feasibility of permeation grouting for constructing subsurface barriers

    SciTech Connect

    Dwyer, B.P.

    1994-04-01

    Efforts are being made to devise technologies that provide interim containment of waste sites while final remediation alternatives are developed. Permeation grouting, a technique used extensively in the civil and mining engineering industry has been investigated as a method for emplacing a subsurface containment barrier beneath existing waste sites. Conceptually an underlying barrier is placed by injecting grout into the formation at less than fracturing pressure from a series of directionally drilled boreholes beneath the waste site. This study evaluated the penetration and performance characteristics in varying soil conditions of four different grout materials (two microfine cements, mineral wax, and sodium silicate) at a field scale. Field testing consisted of grout injection via sleeve (tube-a`-manchette) pipe into both vertical and horizontal borehole configurations at the Mixed Waste Landfill Integrated Demonstration site at Sandia National Laboratories. Prior to, during, and after grout injection non-intrusive geophysical techniques were used to map grout flow. Following the tests, the site was excavated to reveal details of the grout permeation, and grouted soil samples were cored for laboratory characterization. The non-intrusive and intrusive grout mapping showed preferential flow patterns, i.e., the grout tended to follow the path of least resistance. Preliminary testing indicates that permeation grouting is a feasible method for emplacing a low permeability subsurface barrier in the semi-arid unconsolidated alluvial soils common to the Southwest. Despite the success of this project, difficulties in predicting grout flow in heterogeneous soils and non-intrusive methods for imaging grout location and continuity are issues that need more attention.

  14. Explorando nuevos horizontes en NASA

    NASA Astrophysics Data System (ADS)

    Villanueva, G. L.

    A pesar de la incesante expansión del Universo iniciada con el Big Bang 14 mil millones de años atrás, nuestro Universo se siente cada día más cercano. La inquebrantable vocación de la humanidad por descubrir nuevos horizontes ha permitido el acercamiento de civilizaciones en nuestro planeta y nos ha permitido conocer nuestro lugar en el Universo como nunca antes. En este artículo presento una breve sinopsis de nuestro trabajo que se relaciona con diversas investigaciones con implicaciones astrobiológicas, desde el origen de los ingredientes de la "sopa de la vida", hasta la evolución y composición de la atmósfera de Marte.

  15. Seismic Survey Report for Central Nevada Test Area, Subsurface, Correction Action Unit 443, Revision 1

    SciTech Connect

    2008-12-19

    The seismic survey was successful in imaging the water table and underlying structures at the site. The configuration of the water table reflector confirms the general southeast horizontal flow direction in the alluvial aquifer. Offsets in the water table reflector, both at known faults that reach the surface and at subsurface faults not previously recognized, indicate that both extension and blast-related faults are barriers to lateral groundwater flow. The results from this study have been used to optimally locate two new wells designed to monitor head levels and possible contaminant migration in the alluvial aquifer at CTNA.

  16. Wave-Based Subsurface Guide Star

    SciTech Connect

    Lehman, S K

    2011-07-26

    Astronomical or optical guide stars are either natural or artificial point sources located above the Earth's atmosphere. When imaged from ground-based telescopes, they are distorted by atmospheric effects. Knowing the guide star is a point source, the atmospheric distortions may be estimated and, deconvolved or mitigated in subsequent imagery. Extending the guide star concept to wave-based measurement systems to include acoustic, seismo-acoustic, ultrasonic, and radar, a strong artificial scatterer (either acoustic or electromagnetic) may be buried or inserted, or a pre-existing or natural sub-surface point scatterer may be identified, imaged, and used as a guide star to determine properties of the sub-surface volume. That is, a data collection is performed on the guide star and the sub-surface environment reconstructed or imaged using an optimizer assuming the guide star is a point scatterer. The optimization parameters are the transceiver height and bulk sub-surface background refractive index. Once identified, the refractive index may be used in subsequent reconstructions of sub-surface measurements. The wave-base guide star description presented in this document is for a multimonostatic ground penetrating radar (GPR) but is applicable to acoustic, seismo-acoustic, and ultrasonic measurement systems operating in multimonostatic, multistatic, multibistatic, etc., modes.

  17. Medical examinations for pilots.

    PubMed Central

    Nicholson, P. J.

    1995-01-01

    High altitude is an environment that is alien to man. Stressors associated with the mechanics of flight include motion and acceleration forces applied in three vectors and in degrees that are foreign to the human vestibular apparatus. Furthermore, the work patterns of a pilot can interfere with lifestyle and circadian rhythms. Therefore medical fitness is an important consideration in determining an individual's suitability to exercise a pilot's licence. The medical standards applied depend on the type of aircraft flown and the duties expected of a pilot. There are three broad categories of pilot. In ascending order of stringency of medical standards these are the private pilot, the professional pilot and the military pilot. PMID:7494767

  18. Microbial activities in deep subsurface environments

    SciTech Connect

    Phelps, T.J.; Raione, E.G.; White, D.C. |; Fliermans, C.B.

    1988-12-31

    Activities of microorganisms residing in terrestrial deep subsurface sediments were examined in forty-six sediment samples from three aseptically sampled boreholes. Radiolabeled time course experiments assessing in situ microbial activities were initiated within 30 minutes of core recovery. [{sup 14}C-1-] Acetate incorporation into lipids. [methyl-{sup 3}H-]thymidine incorporation into DNA, [{sup 14}C-2-]acetate and [{sup 14}C-U-]glucose mineralization in addition to microbial enrichment and enumeration studies were examined in surface and subsurface sediments. Surface soils contained the greatest biomass and activities followed by the shallow aquifer zones. Water saturated subsurface sediments exhibited three to four orders of magnitude greater activity and culturable microorganisms than the dense clay zones. Regardless of depth, sediments which contained more than 20% clays exhibited the lowest activities and culturable microorganisms.

  19. Anthropogenic effects on subsurface temperature in Bangkok

    NASA Astrophysics Data System (ADS)

    Taniguchi, M.

    2006-09-01

    Subsurface temperatures in Bangkok, where population and density increase rapidly, were analyzed to evaluate the effects of surface warming due to urbanization. The magnitude of surface warming evaluated from subsurface temperature in Bangkok was 1.7°C which agreed with meteorological data during the last 50 years. The depth apart from steady thermal gradient, which shows an indicator of the magnitude of surface warming due to additional heat from urbanization, was deeper at the center of the city than in the suburb areas of Bangkok. In order to separate surface warming effects into global warming effect and urbanization effect, analyses of subsurface temperature have been done depending on the distance from the city center. The results show that the expansion of urbanization in Bangkok reaches up to 80 km from the city center.

  20. Autonomous microexplosives subsurface tracing system final report.

    SciTech Connect

    Engler, Bruce Phillip; Nogan, John; Melof, Brian Matthew; Uhl, James Eugene; Dulleck, George R., Jr.; Ingram, Brian V.; Grubelich, Mark Charles; Rivas, Raul R.; Cooper, Paul W.; Warpinski, Norman Raymond; Kravitz, Stanley H.

    2004-04-01

    The objective of the autonomous micro-explosive subsurface tracing system is to image the location and geometry of hydraulically induced fractures in subsurface petroleum reservoirs. This system is based on the insertion of a swarm of autonomous micro-explosive packages during the fracturing process, with subsequent triggering of the energetic material to create an array of micro-seismic sources that can be detected and analyzed using existing seismic receiver arrays and analysis software. The project included investigations of energetic mixtures, triggering systems, package size and shape, and seismic output. Given the current absence of any technology capable of such high resolution mapping of subsurface structures, this technology has the potential for major impact on petroleum industry, which spends approximately $1 billion dollar per year on hydraulic fracturing operations in the United States alone.

  1. Urban heat island in the subsurface

    NASA Astrophysics Data System (ADS)

    Ferguson, Grant; Woodbury, Allan D.

    2007-12-01

    The urban heat island effect has received significant attention in recent years due to the possible effect on long-term meteorological records. Recent studies of this phenomenon have suggested that this may not be important to estimates of regional climate change once data are properly corrected. However, surface air temperatures within urban environments have significant variation, making correction difficult. In the current study, we examine subsurface temperatures in an urban environment and the surrounding rural area to help characterize the nature of this variability. The results of our study indicate that subsurface temperatures are linked to land-use and supports previous work indicating that the urban heat island effect has significant and complex spatial variability. In most situations, the relationship between subsurface and surface processes cannot be easily determined, indicating that previous studies that relying on such a linkage may require further examination.

  2. Subsurface Contaminants Focus Area annual report 1997

    SciTech Connect

    1997-12-31

    In support of its vision for technological excellence, the Subsurface Contaminants Focus Area (SCFA) has identified three strategic goals. The three goals of the SCFA are: Contain and/or stabilize contamination sources that pose an imminent threat to surface and ground waters; Delineate DNAPL contamination in the subsurface and remediate DNAPL-contaminated soils and ground water; and Remove a full range of metal and radionuclide contamination in soils and ground water. To meet the challenges of remediating subsurface contaminants in soils and ground water, SCFA funded more than 40 technologies in fiscal year 1997. These technologies are grouped according to the following product lines: Dense Nonaqueous-Phase Liquids; Metals and Radionuclides; Source Term Containment; and Source Term Remediation. This report briefly describes the SCFA 1997 technologies and showcases a few key technologies in each product line.

  3. Automatic control of an aircraft employing outboard horizontal stabilizers

    NASA Astrophysics Data System (ADS)

    Mukherjee, Jason S.

    2000-10-01

    This dissertation concerns the study of radio-operated control of an aircraft using fixed gain and adaptive controllers. The real-time feedback control system is developed to enhance the flying qualities of an experimental model aircraft. The non-conventional flight dynamics of the Outboard Horizontal Stabilizer (OHS) aircraft cause significant differences in the piloting of the aircraft. The control system was added to augment stability as well as to adjust the flight characteristics so that the OHS aircraft handles similar to a conventional aircraft. The control system design process, as applied to recent innovations in aircraft design, is followed. The Outboard Horizontal Stabilizer concept is a non-conventional aircraft, designed to take advantage of the normally wasted energy developed by the wing tip vortices. The research is based on a remotely-controlled OHS aircraft fitted with various sensors and telemetry as part of a real time feedback control system. Fixed gain Linear Quadratic controllers are first applied to the aircraft and result in a dramatic increase in performance at a nominal operating condition. Non-linearities in the OHS aircraft behavior and a wide operating range demanded the development of a variable gain adaptive controller utilizing a parameter estimation scheme to model the plant. The adaptive LQR gain-scheduled controller that emerged gave good performance over a wide flight envelope.

  4. MSTS - Multiphase Subsurface Transport Simulator theory manual

    SciTech Connect

    White, M.D.; Nichols, W.E.

    1993-05-01

    The US Department of Energy, through the Yucca Mountain Site Characterization Project Office, has designated the Yucca Mountain site in Nevada for detailed study as the candidate US geologic repository for spent nuclear fuel and high-level radioactive waste. Site characterization will determine the suitability of the Yucca Mountain site for the potential waste repository. If the site is determined suitable, subsequent studies and characterization will be conducted to obtain authorization from the Nuclear Regulatory Commission to construct the potential waste repository. A principal component of the characterization and licensing processes involves numerically predicting the thermal and hydrologic response of the subsurface environment of the Yucca Mountain site to the potential repository over a 10,000-year period. The thermal and hydrologic response of the subsurface environment to the repository is anticipated to include complex processes of countercurrent vapor and liquid migration, multiple-phase heat transfer, multiple-phase transport, and geochemical reactions. Numerical simulators based on mathematical descriptions of these subsurface phenomena are required to make numerical predictions of the thermal and hydrologic response of the Yucca Mountain subsurface environment The engineering simulator called the Multiphase Subsurface Transport Simulator (MSTS) was developed at the request of the Yucca Mountain Site Characterization Project Office to produce numerical predictions of subsurface flow and transport phenomena at the potential Yucca Mountain site. This document delineates the design architecture and describes the specific computational algorithms that compose MSTS. Details for using MSTS and sample problems are given in the {open_quotes}User`s Guide and Reference{close_quotes} companion document.

  5. Improving the biodegradative capacity of subsurface bacteria

    SciTech Connect

    Romine, M.F.; Brockman, F.J.

    1993-04-01

    The continual release of large volumes of synthetic materials into the environment by agricultural and industrial sources over the last few decades has resulted in pollution of the subsurface environment. Cleanup has been difficult because of the relative inaccessibility of the contaminants caused by their wide dispersal in the deep subsurface, often at low concentrations and in large volumes. As a possible solution for these problems, interest in the introduction of biodegradative bacteria for in situ remediation of these sites has increased greatly in recent years (Timmis et al. 1988). Selection of biodegradative microbes to apply in such cleanup is limited to those strains that can survive among the native bacterial and predator community members at the particular pH, temperature, and moisture status of the site (Alexander, 1984). The use of microorganisms isolated from subsurface environments would be advantageous because the organisms are already adapted to the subsurface conditions. The options are further narrowed to strains that are able to degrade the contaminant rapidly, even in the presence of highly recalcitrant anthropogenic waste mixtures, and in conditions that do not require addition of further toxic compounds for the expression of the biodegradative capacity (Sayler et al. 1990). These obstacles can be overcome by placing the genes of well-characterized biodegradative enzymes under the control of promoters that can be regulated by inexpensive and nontoxic external factors and then moving the new genetic constructs into diverse groups of subsurface microbes. ne objective of this research is to test this hypothesis by comparing expression of two different toluene biodegradative enzymatic pathways from two different regulatable promoters in a variety of subsurface isolates.

  6. Induction heaters used to heat subsurface formations

    DOEpatents

    Nguyen, Scott Vinh [Houston, TX; Bass, Ronald M [Houston, TX

    2012-04-24

    A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300.degree. C.

  7. Apparatus for passive removal of subsurface contaminants

    DOEpatents

    Pemberton, Bradley E.; May, Christopher P.; Rossabi, Joseph

    1997-01-01

    An apparatus is provided which passively removes contaminated gases from a subsurface. The apparatus includes a riser pipe extending into a subsurface which has an exterior end in fluid communication with a valve. When well pressure is greater than atmospheric pressure, the valve opens to release contaminants into the atmosphere, and when well pressure is less than atmospheric pressure, the valve closes to prevent flow of air into the well. The valve assembly of the invention comprises a lightweight ball which is lifted from its valve seat with a slight pressure drop between the well and the atmosphere.

  8. Radar Soundings of the Subsurface of Mars

    NASA Technical Reports Server (NTRS)

    Picardi, Giovanni; Plaut, Jeffrey J.; Biccari, Daniela; Bombaci, Ornella; Calabrese, Diego; Cartacci, Marco; Cicchetti, Andrea; Clifford, Stephen M.; Edenhofer, Peter; Farrell, William M.; Federico, Costanzo; Frigeri, Alessandro; Gurnett, Donald A.; Hagfors, Tor; Heggy, Essam; Herique, Alain; Huff, Richard L.; Ivanov, Anton B.; Johnson, William T. K.; Jordan, Rolando L.; Kirchner, Donald L.; Kofman, Wlodek; Leuschen, Carlton J.; Nielsen, Erling; Orosei, Roberto

    2005-01-01

    The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.

  9. Subsurface Microbes Expanding the Tree of Life

    SciTech Connect

    Banfield, Jillian

    2015-05-11

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  10. Apparatus for passive removal of subsurface contaminants

    DOEpatents

    Pemberton, B.E.; May, C.P.; Rossabi, J.

    1997-06-24

    An apparatus is provided which passively removes contaminated gases from a subsurface. The apparatus includes a riser pipe extending into a subsurface which has an exterior end in fluid communication with a valve. When well pressure is greater than atmospheric pressure, the valve opens to release contaminants into the atmosphere, and when well pressure is less than atmospheric pressure, the valve closes to prevent flow of air into the well. The valve assembly of the invention comprises a lightweight ball which is lifted from its valve seat with a slight pressure drop between the well and the atmosphere. 7 figs.

  11. Heating systems for heating subsurface formations

    SciTech Connect

    Nguyen, Scott Vinh; Vinegar, Harold J.

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  12. Subsurface Microbes Expanding the Tree of Life

    ScienceCinema

    Banfield, Jillian

    2016-07-12

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  13. On the Hydraulics of Flowing Horizontal Wells

    NASA Astrophysics Data System (ADS)

    Bian, A.; Zhan, H.

    2003-12-01

    A flowing horizontal well is a special type of horizontal well that does not have pumping/injecting facility. The discharge rate of a flowing horizontal well is controlled by the hydraulic gradient between the aquifer and the well and it generally varies with time if the hydraulic head of the aquifer is transient. This type of well has been used in landslide control, mining dewatering, water table control, underground water transportation through a horizontal tunnel, agricultural water drainage, and other applications. Flowing horizontal wells have quite different hydrodynamic characteristics from horizontal wells with fixed pumping or injecting rates because their discharge rates are functions of the aquifer hydraulic heads (Zhan et al, 2001; Zhan and Zlotnik, 2002). Hydraulics of flowing horizontal wells have rarely been studied although the hydraulics of flowing vertical wells have been extensively investigated before. The purpose of this paper is to obtain analytical solutions of groundwater flow to a flowing horizontal-well in a confined aquifer, in a water table aquifer without precipitation, and in a water table aquifer with precipitation. The functions of the flowing horizontal well discharge rates versus time will be obtained under above mentioned different aquifer conditions. The relationships of the aquifer hydraulic heads versus the discharge rates of the well will be investigated. The rate of water table decline due to the dewatering of the well will also be computed, and this solution is particularly useful for landslide control and mining dewatering. The theoretical solutions will be compared with results of experiments that will be conducted in the hydrological laboratory at Texas A&M University. Reference: Zhan, H., Wang, L.V., and Park, E, On the horizontal well pumping tests in the anisotropic confined aquifers, J. hydrol., 252, 37-50, 2001. Zhan, H., and Zlotnik, V. A., Groundwater flow to a horizontal or slanted well in an unconfined aquifer

  14. Subsurface clade of Geobacteraceae that predominates in a diversity of Fe(III)-reducing subsurface environments

    USGS Publications Warehouse

    Holmes, Dawn E.; O'Neil, Regina A.; Vrionis, Helen A.; N'Guessan, Lucie A.; Ortiz-Bernad, Irene; Larrahondo, Maria J.; Adams, Lorrie A.; Ward, Joy A.; Nicoll , Julie S.; Nevin, Kelly P.; Chavan, Milind A.; Johnson, Jessica P.; Long, Philip E.; Lovely, Derek R.

    2007-01-01

    There are distinct differences in the physiology of Geobacter species available in pure culture. Therefore, to understand the ecology of Geobacter species in subsurface environments, it is important to know which species predominate. Clone libraries were assembled with 16S rRNA genes and transcripts amplified from three subsurface environments in which Geobacter species are known to be important members of the microbial community: (1) a uranium-contaminated aquifer located in Rifle, CO, USA undergoing in situ bioremediation; (2) an acetate-impacted aquifer that serves as an analog for the long-term acetate amendments proposed for in situ uranium bioremediation and (3) a petroleum-contaminated aquifer in which Geobacter species play a role in the oxidation of aromatic hydrocarbons coupled with the reduction of Fe(III). The majority of Geobacteraceae 16S rRNA sequences found in these environments clustered in a phylogenetically coherent subsurface clade, which also contains a number of Geobacter species isolated from subsurface environments. Concatamers constructed with 43 Geobacter genes amplified from these sites also clustered within this subsurface clade. 16S rRNA transcript and gene sequences in the sediments and groundwater at the Rifle site were highly similar, suggesting that sampling groundwater via monitoring wells can recover the most active Geobacter species. These results suggest that further study of Geobacter species in the subsurface clade is necessary to accurately model the behavior of Geobacter species during subsurface bioremediation of metal and organic contaminants.

  15. The history of horizontal glottectomy.

    PubMed

    Folz, Benedikt J; Rinaldo, Alessandra; Silver, Carl E; Ferlito, Alfio

    2010-02-01

    The history of horizontal glottectomy (HG) for the treatment of bilateral vocal cord lesions is not entirely clear. The present investigation analyzes the history of HG on the basis of cross-referenced database searches in general and professional medical literature databases. Books, original historical articles and medical history reviews were evaluated. The initial work was done by Moser in years from 1959 to 1965, and in 1961 he published the first paper on HG. Follow-up publications were reported in 1977 by Gramowski and in 1984 by Wilke. In 1970, Romanian laryngologists headed by Calaraşu described a HG via excision of a rhomboid-shaped portion of the thyroid cartilage, but the authors had neither sufficient numbers of patients nor a sufficiently long follow-up for the procedure to gain widespread acceptance. In 1978, Calearo and Teatini described HG similar to Calaraşu's method, but slightly more extended by the eventual inclusion of an arytenoid cartilage in the operative specimen. Theses authors have often been credited as the originators of the procedure, but actually were the first to publish in an English language journal. The procedure, while quite effective for treatment of bilateral and anterior commissure lesions, has never gained general acceptance in the United States, and in current practice, has been supplanted by endoscopic and non-surgical treatments.

  16. Widespread horizontal transfer of retrotransposons

    PubMed Central

    Walsh, Ali Morton; Kortschak, R. Daniel; Gardner, Michael G.; Bertozzi, Terry; Adelson, David L.

    2013-01-01

    In higher organisms such as vertebrates, it is generally believed that lateral transfer of genetic information does not readily occur, with the exception of retroviral infection. However, horizontal transfer (HT) of protein coding repetitive elements is the simplest way to explain the patchy distribution of BovB, a long interspersed element (LINE) about 3.2 kb long, that has been found in ruminants, marsupials, squamates, monotremes, and African mammals. BovB sequences are a major component of some of these genomes. Here we show that HT of BovB is significantly more widespread than believed, and we demonstrate the existence of two plausible arthropod vectors, specifically reptile ticks. A phylogenetic tree built from BovB sequences from species in all of these groups does not conform to expected evolutionary relationships of the species, and our analysis indicates that at least nine HT events are required to explain the observed topology. Our results provide compelling evidence for HT of genetic material that has transformed vertebrate genomes. PMID:23277587

  17. Sub-Surface Windscreen for the Measurement of Outdoor Infrasound

    NASA Technical Reports Server (NTRS)

    Shams, Qamar A.; Burkett, Cecil G., Jr.; Comeaux, Toby; Zuckerwar, Allan J.; Weistroffer, George R.

    2008-01-01

    A windscreen has been developed that features two advantages favorable for the measurement of outdoor infrasound. First, the sub-surface location, with the top of the windscreen flush with the ground surface, minimizes the mean velocity of the impinging wind. Secondly, the windscreen material (closed cell polyurethane foam) has a sufficiently low acoustic impedance (222 times that of air) and wall thickness (0.0127 m) to provide a transmission coefficient of nearly unity over the infrasonic frequency range (0-20 Hz). The windscreen, a tightly-sealed box having internal dimensions of 0.3048 x 0.3048 x 0.3556 m, contains a microphone, preamplifier, and a cable feed thru to an external power supply. Provisions are made for rain drainage and seismic isolation. A three-element array, configured as an equilateral triangle with 30.48 m spacing and operating continuously in the field, periodically receives highly coherent signals attributed to emissions from atmospheric turbulence. The time delays between infrasonic signals received at the microphones permit determination of the bearing and elevation of the sources, which correlate well with locations of pilot reports (PIREPS) within a 320 km radius about the array. The test results are interpreted to yield spectral information on infrasonic emissions from clear air turbulence.

  18. Is Europa's Subsurface Water Ocean Warm?

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.; Ekholm, A. G.; Showman, A. P.; Lorenz, R. D.

    2002-01-01

    Europa's subsurface water ocean may be warm: that is, at the temperature of water's maximum density. This provides a natural explanation of chaos melt-through events and leads to a correct estimate of the age of its surface. Additional information is contained in the original extended abstract.

  19. Lateral gene transfer in the subsurface

    SciTech Connect

    Barkay, Tamar; Sobecky, Patricia

    2007-08-27

    Lateral gene transfer (LGT) is an important adaptive mechanism among prokaryotic organisms. This mechanism is particularly important for the response of microorganisms to changing environmental conditions because it facilitates the transfer of a large number of genes and their rapid expression. Together the transferred genes promote rapid genetic and metabolic changes that may enhance survival to newly established and sometimes hostile environmental conditions. The goal of our project was to examine if and how LGT enhances microbial adaptation to toxic heavy metals in subsurface environments that had been contaminated by mixed wastes due to activities associated with the production of nuclear energy and weapons. This task has been accomplished by dividing the project to several sub-tasks. Thus, we: (1) Determined the level of resistance of subsurface bacterial isolates to several toxic metals, all identified as pollutants of concern in subsurface environments; (2) Designed, tested, and applied, a molecular approach that determined whether metal resistance genes had evolved by LGT among subsurface bacteria; and (3) Developed a DNA hybridization array for the identification of broad host range plasmids and of metal resistance plasmids. The results are briefly summarized below with references to published papers and manuscripts in preparation where details about our research can be found. Additional information may be found in copies of our published manuscripts and conference proceedings, and our yearly reports that were submitted through the RIMS system.

  20. Irrigation strategies using subsurface drip irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drip irrigation (SDI) is practiced on approximately 60,000 ha in the Texas High Plains region of the USA. Adoption of SDI continues to increase in the region. This has been attributed to record drought in Texas and the US Southwest in recent years, declining irrigation well yields, and ev...

  1. BIODEGRADATION OF ATRAZINE IN SUBSURFACE ENVIRONMENTS

    EPA Science Inventory

    The pesticide atrazine is frequently detected in ground water, including ground water used as drinking water. Little information is available on the fate of atrazine in the subsurface, including its biodegradability. The objectives of this study were to evaluate the biodegradabil...

  2. Biomarker Preservation Potential of Subsurface Ecosystems

    NASA Astrophysics Data System (ADS)

    Onstott, T. C.; Harris, R. L.; Sherwood Lollar, B.; Pedersen, K. A.; Colwell, F. S.; Pfiffner, S. M.; Phelps, T. J.; Kieft, T. L.; Bakermans, C.

    2016-05-01

    If surface life emerged on Mars it may have succumbed to a Gaian bottleneck, whereas subsurface life would have continued to grow and evolve sheltered in rocks with sub-freezing saline pore water and their remains preserved in excavated rock.

  3. Characterization of imidacloprid availability in subsurface soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Degradation and sorption/desorption are the most important processes affecting the leaching of pesticides through soil because they control the amount of pesticide available for transport. Once pesticides move past the surface soil layers, variations in subsurface soil physical, chemical, and biolog...

  4. Methods for forming long subsurface heaters

    DOEpatents

    Kim, Dong Sub

    2013-09-17

    A method for forming a longitudinal subsurface heater includes longitudinally welding an electrically conductive sheath of an insulated conductor heater along at least one longitudinal strip of metal. The longitudinal strip is formed into a tubular around the insulated conductor heater with the insulated conductor heater welded along the inside surface of the tubular.

  5. Global horizontal shear velocity structure

    NASA Astrophysics Data System (ADS)

    Ho, T. M.; Priestley, K. F.; Debayle, E.; Chapman, C. H.

    2013-12-01

    Rayleigh wave data have been used extensively to produce various SV-wave tomographic models of the upper mantle. Love wave data are more difficult to deal with resulting in fewer SH-wave tomographic models. The models also do not incorporate higher mode information which can place better constraints on the model. We have assembled a large, horizontal component data set and have inverted these seismogram in the 4-13 mHz band including higher mode information. We use a version of the automated waveform inversion technique modified for Love waves. We have explored the effects of various crustal models and because of the greater sensitivity of Love waves to the crustal structure, at present, we limit our inversion to this lower frequency band. Due to the higher mode Love waves having similar group velocities between the periods of 50-100 s for oceanic paths, interference occurs which partition techniques have difficulties dealing with. The modified technique used here does not require partitioning the data and can help extract the data more easily at these period bands. We present a new VSH and Xi model for the upper mantle. High VSH extending to about 250 km depth occurs beneath the cratons and Tibet; Low VSH occurs beneath the mid-ocean ridges, the back arc basins and beneath the Afar hotspot. The Xi model shows that VSH is greater by approximately 3% at 100km and rapidly drops to zero at around 300 km depth where the mantle becomes isotropic. At 250 km depth, there are regions where SV is greater than SH, suggesting more vertical flow beneath mid-ocean ridges at these depths.

  6. Subsurface barrier verification technologies, informal report

    SciTech Connect

    Heiser, J.H.

    1994-06-01

    One of the more promising remediation options available to the DOE waste management community is subsurface barriers. Some of the uses of subsurface barriers include surrounding and/or containing buried waste, as secondary confinement of underground storage tanks, to direct or contain subsurface contaminant plumes and to restrict remediation methods, such as vacuum extraction, to a limited area. To be most effective the barriers should be continuous and depending on use, have few or no breaches. A breach may be formed through numerous pathways including: discontinuous grout application, from joints between panels and from cracking due to grout curing or wet-dry cycling. The ability to verify barrier integrity is valuable to the DOE, EPA, and commercial sector and will be required to gain full public acceptance of subsurface barriers as either primary or secondary confinement at waste sites. It is recognized that no suitable method exists for the verification of an emplaced barrier`s integrity. The large size and deep placement of subsurface barriers makes detection of leaks challenging. This becomes magnified if the permissible leakage from the site is low. Detection of small cracks (fractions of an inch) at depths of 100 feet or more has not been possible using existing surface geophysical techniques. Compounding the problem of locating flaws in a barrier is the fact that no placement technology can guarantee the completeness or integrity of the emplaced barrier. This report summarizes several commonly used or promising technologies that have been or may be applied to in-situ barrier continuity verification.

  7. Detailed subsurface descriptions drive record breaking wells in the deep water Gulf of Mexico

    SciTech Connect

    Guderjahn, C.; Hill, P.; Blankenship, C.; Epps, D.

    1996-12-31

    Increased well productivity is motivating development teams to successfully complete record breaking wells. Advances in subsurface description are leveraging with breakthroughs in drilling and completion technology to achieve new levels of financial performance. Gulf of Mexico industry and company records have recently been set in extended reach drilling, horizontal drilling, curvilinear completions, and frac-packed high angle completions. These advanced well designs are establishing new production records in the deep water Gulf of Mexico. Improvements in 3D seismic imaging, geologic depositional models, and reservoir pressure predictions are enhancing the subsurface model such that significant productivity benefits are achieved by targeting completions in specific geometries. Advances in directional drilling accuracy and the utilization of synthetic oil-base muds are assuring that wells are placed precisely on target. In the BP operated Pompano Field horizontal wells have been placed down turbidite channel axes, high angle wells are used to connect separate reservoir compartments, extended reach wells have been steered away from over-pressured sections identified from seismic, and a multi-lateral completion is next on the drilling schedule. Multi-disciplinary innovation and focused teamwork is also changing behavioral working styles. It is now accepted that the {open_quote}teams{close_quotes} consist of geoscientists, engineers, and offshore drilling hands. Well planning takes place both on the rig floor and in the office. The payoff for further integration is higher profits, lower risk, and a safer working environment.

  8. Detailed subsurface descriptions drive record breaking wells in the deep water Gulf of Mexico

    SciTech Connect

    Guderjahn, C.; Hill, P.; Blankenship, C.; Epps, D. )

    1996-01-01

    Increased well productivity is motivating development teams to successfully complete record breaking wells. Advances in subsurface description are leveraging with breakthroughs in drilling and completion technology to achieve new levels of financial performance. Gulf of Mexico industry and company records have recently been set in extended reach drilling, horizontal drilling, curvilinear completions, and frac-packed high angle completions. These advanced well designs are establishing new production records in the deep water Gulf of Mexico. Improvements in 3D seismic imaging, geologic depositional models, and reservoir pressure predictions are enhancing the subsurface model such that significant productivity benefits are achieved by targeting completions in specific geometries. Advances in directional drilling accuracy and the utilization of synthetic oil-base muds are assuring that wells are placed precisely on target. In the BP operated Pompano Field horizontal wells have been placed down turbidite channel axes, high angle wells are used to connect separate reservoir compartments, extended reach wells have been steered away from over-pressured sections identified from seismic, and a multi-lateral completion is next on the drilling schedule. Multi-disciplinary innovation and focused teamwork is also changing behavioral working styles. It is now accepted that the [open quote]teams[close quotes] consist of geoscientists, engineers, and offshore drilling hands. Well planning takes place both on the rig floor and in the office. The payoff for further integration is higher profits, lower risk, and a safer working environment.

  9. Analysis of nitrogen removal processes in a subsurface flow carbonate sand filter treating municipal wastewater.

    PubMed

    Kløve, Bjørn; Søvik, Anne-Kristine; Holtan-Hartwig, Liv

    2005-01-01

    Controlled experiments were carried out in a mesoscale subsurface flow sand filter treating municipal wastewater from a single household. The system consisted of a 50 cm high vertical flow column (pre-filter) with unsaturated flow and a 3 m long horizontal subsurface flow unit (main filter) with saturated flow. Fluxes of nitrogen and carbon were analyzed in 4 different operating conditions (low and high loading, with and without the prefilter unit). Water samples were taken from the inlet, the outlet and within the sand filter at different depths and locations and analysed for water quality (Tot N, NO3-N, NH4-N, TOC, DOC, CODcr, BOD5, SS, pH, and EC) and dissolved gas content (N2O, CH4, and CO2). Emissions of N2O, CH4, and CO2 were measured with the closed-chamber technique adjacent to water quality sampling points. The results show that prefiltering in a vertical, unsaturated flow column changed the incoming ammonium to nitrate during low loading. During high loading part of the ammonium nitrified in the pre-filter was lost by denitrification. Within the horizontal main filter there were two pathways for the incoming nitrate: denitrification and dissimilatory nitrate reduction to ammonium (DNRA).

  10. Unmanned Aircraft: A Pilot's Perspective

    NASA Technical Reports Server (NTRS)

    Pestana, Mark E.

    2010-01-01

    This slide presentation reviews some of the challenges of "piloting" a unmanned aircraft. The topic include the pilot-vehicle interact design, the concept of pilot/operator, and role of NASA's Ikhana UAS in the western states fire mission.

  11. Theory and numerical application of subsurface flow and transport for transient freezing conditions

    SciTech Connect

    White, M.D.

    1995-04-01

    Protective barriers are being investigated for the containment of radioactive waste within subsurface environments. Predicting the effectiveness of cryogenic barriers and near-surface barriers in temperate or arctic climates requires capabilities for numerically modeling subsurface flow and transport for freezing soil conditions. A predictive numerical model is developed herein to simulate the flow and transport of radioactive solutes for three-phase (water-ice-air) systems under freezing conditions. This physically based model simulates the simultaneous flow of water, air, heat, and radioactive solutes through variably saturated and variably frozen geologic media. Expressions for ice (frozen water) and liquid water saturations as functions of temperature, interfacial pressure differences, and osmotic potential are developed from nonhysteretic versions of the Brooks and Corey and van Genuchten functions for soil moisture retention. Aqueous relative permeability functions for variably saturated and variably frozen geologic media are developed from the Mualem and Burdine theories for predicting relative permeability of unsaturated soil. Soil deformations, caused by freezing and melting transitions, are neglected. Algorithms developed for predicting ice and liquid water saturations and aqueous-phase permeabilities were incorporated into the finite-difference based numerical simulator STOMP (Subsurface Transport Over Multiple Phases). Application of the theory is demonstrated by the solution of heat and mass transport in a horizontal cylinder of partially saturated porous media with differentially cooled ends, with the colder end held below the liquid water freezing point. This problem represents an essential capability for modeling cryogenic barriers in variably saturated geologic media.

  12. Soil Samplers: New Techniques for Subsurface Sampling for Volatile Organic Compounds

    SciTech Connect

    Susan Sorini; John Schabron; Joseph Rovani; Mark Sanderson

    2009-03-31

    Soil sampling techniques for volatile organic analysis must be designed to minimize loss of volatile organic compounds (VOCs) from the soil that is being sampled. Preventing VOC loss from soil cores that are collected from the subsurface and brought to the surface for subsampling is often difficult. Subsurface bulk sample retrieval systems are designed to obtain intact cylindrical cores of soil ranging anywhere from one to four inches in diameter, and one to several feet in length. The current technique that is used to subsample these soil cores for VOC analysis is to expose a horizontal section of the soil core to the atmosphere; screen the exposed soil using a photoionization detector (PID) or other appropriate device to locate contamination in the soil core; and use a hand-operated coring tool to collect samples from the exposed soil for analysis. Because the soil core can be exposed to the atmosphere for a considerable length of time during screening and sample collection, the current sub-sampling technique provides opportunity for VOCs to be lost from the soil. This report describes three alternative techniques from the current technique for screening and collecting soil samples from subsurface soil cores for VOC analysis and field testing that has been done to evaluate the techniques. Based on the results of the field testing, ASTM D4547, Standard Guide for Sampling Waste and Soils for Volatile Organic Compounds, was revised to include information about the new techniques.

  13. Design, implementation, and completion of a horizontal tight gas wellbore - case study: Green River Basin, Wyoming

    SciTech Connect

    Billingsley, R.L.; Evans, L.W.; Anderson, T.M.

    1995-06-01

    In September, 1993 Amoco Production Company began drilling the Champlin 254B No. 2H, a horizontal well test located near the Wamsutter Arch, southwestem Wyoming. The Champlin 254B No. 2H was designed to confirm a fractured reservoir concept and to test the economic viability of a horizontal wellbore in the Almond fm.. The wellbore was designed to determine real-time, the fracture direction and the optimum horizontal leg direction within the confines of the drilling permit. A deviated pilot hole was drilled to optimize our ability to cross vertical natural fractures. MWD gamma-ray, oriented core, a vertical seismic profile, Formation Microimager, and a robust suite of electric logs were obtained to gain information on the presence and orientation of fractures before kickoff for the horizontal leg. Electromagnetic goniometry was used onsite to orient fractures in core. Log and core data were consistent and a wellbore trajectory of due South was chosen. A two thousand foot horizontal wellbore was drilled, 1700 feet of which is in the upper Almond formation productive zone. MWD gamma-ray, three 30` cores, Formation Microscanner logs, and a density-neutron log were obtained in the horizontal hole. This wellbore was completed open-hole with a stabilized gas rate of 1 mmcfd. In May, 1994 a portion of the original wellbore collapsed and a replacement horizontal leg was drilled. Oil-based mud and rotary BOP`s were utilized to minimize damage and invasion to the reservoir. Reservoir pressures encountered in the redrill indicate that depletion along the original wellbore had begun. The redrill was completed open-hole with a pre-perforated (every third joint) 5 1/2 inches liner and also stabilized at a rate of 1 mmcfd.

  14. Recovery of bypassed oil in the Dundee formation using horizontal drains

    SciTech Connect

    Wood, J.R.

    1996-04-30

    The principal objective of this project is to demonstrate the feasibility and economic success of producing oil from abandoned or nearly abandoned fields in the Dundee Formation of Central Michigan using horizontal drilling technology. A site for a horizontal well was selected in Crystal Field, a nearly-abandoned Dundee oil field in Michigan. This field had produced over 8 million barrels of oil, mostly in the 1930`s and 1940`s. At the height of development, Crystal Field produced from 193 wells, but by 1995, only seven producing wells remained, each producing less than 10 bbls/day. A horizontal well was drilled as a field demonstration pilot, funded through this DOE project, and was immensely successful. Core and logs from the Dundee interval were recovered from a vertical borehole at the same surface location. The horizontal well was brought on production at a rate of 100 bbls/day and is probably capable of producing at a higher rate. `The addition of several horizontal wells, similar to the demonstration well, will likely add another 2 million bbls (or more) to the cumulative production of the field over the next few years. The presence of untapped oil in this Dundee field was dramatically demonstrated and the favorable economics were made clearly evident. Additional project work comprises characterization of 30 Dundee fields in Michigan to aid in determining appropriate candidates for development through horizontal drilling. Further quantification of reservoir parameters such as importance of fracturing, fracture density, and irregularity of the dolomitized surface at the top of the reservoir will help in designing the optimal strategy for horizontal drilling. Technical progress is presented for the following tasks: project management; reservoir characterization; data measurement and analysis; database management; geochemical and basin modeling; and technology transfer.

  15. Tubing and casing buckling in horizontal wells

    SciTech Connect

    Chen, Y.C.; Lin, Y.H.; Cheatham, J.B. )

    1990-02-01

    This paper describes new theoretical results for predicting the buckling behavior of pipe in horizontal holes. Pipe buckling in horizontal holes occurs initially in a sinusoidal mode along the low side of the hole; at higher axial compression a helix is formed. Equations are given for computing the forces required to initiate these different buckling modes. Simple experimental laboratory results confirm the theory. Results presented in this paper apply to friction modeling of buckled tubulars to help predict when pipe can be forced to move along a long section of a horizontal well.

  16. Horizontal fields generated by return strokes

    NASA Technical Reports Server (NTRS)

    Cooray, Vernon

    1991-01-01

    Horizontal fields generated by return strokes play an important role in the interaction of lightning generated electric fields with power lines. In many of the recent investigations on the interaction of lightning electromagnetic fields with power lines, the horizontal field was calculated by employing the expression for the tilt of the electric field of a plane wave propagating over finitely conducting earth. The method is suitable for calculating horizontal fields generated by return strokes at distances as close as 200m. At these close ranges, the use of the wavetilt expression can cause large errors.

  17. On-line testing of a horizontally-baffled flotation column in an operating coal-cleaning plant

    SciTech Connect

    Eisele, T.C.; Kawatra, S.K.

    1995-10-01

    A horizontal-baffle arrangement has been developed to prevent excessive axial mixing in flotation columns. These baffles have been shown in previous work to improve the grade/recovery performance of both a laboratory-scale column and a pilot-scale column. In this paper, results are given for continuous on-line operation of the pilot-scale baffled column in a commercial coal-cleaning plant. These results show its ability to operate for extended periods without plugging, to produce a consistent-quality product even while the feed quality was fluctuating, and to remove much of the pyritic sulfur from the coal.

  18. To Educate Pilots.

    ERIC Educational Resources Information Center

    Roberts, Dayton Y.

    1968-01-01

    As the highly trained ex-military pilots of World War II began to retire from commercial flying, there was concern over the pilot shortage, especially among the airlines with their growing needs. Miami-Dade Junior College, in January 1965, was the first to respond to this need. Although initial enrollment was expected to be small, 150 applications…

  19. SuperPILOT.

    ERIC Educational Resources Information Center

    Weissmann, Stephen M.

    1983-01-01

    SuperPILOT is Apple Computer's new computer assisted instruction authoring language. Provided is a review of SuperPILOT, indicated to be ideally suited for the development of interactive tutorials for the classroom. Includes comments on the language's strengths/weaknesses as well as comments on system requirements and special program features. (JN)

  20. Preparing Pilots for Takeoff

    ERIC Educational Resources Information Center

    Ravage, Barbara

    2012-01-01

    Why would schools consider partnering with a vendor to operate a pilot? Why not just wait until the final product is released? For starters, pilots provide schools with a golden opportunity to get an early look at the software, take it for a test flight, and ask for changes tailored to their operating environment and business needs. In some cases,…

  1. Medical Handbook for Pilots.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC.

    This handbook provides information on an airline pilot's physical and mental status and related medical factors which may affect his/her performance. Contents include information on the physical examination for pilots, the flyer's environment, hypoxia, hyperventilation, gas in the body, the ears, alcohol, drugs and flying, carbon monoxide, vision,…

  2. Performance of a pilot-scale constructed wetland for stormwater runoff and domestic sewage treatment on the banks of a polluted urban river.

    PubMed

    Guo, Weijie; Li, Zhu; Cheng, Shuiping; Liang, Wei; He, Feng; Wu, Zhenbin

    2014-01-01

    To examine the performance of a constructed wetland system on stormwater runoff and domestic sewage (SRS) treatment in central east China, two parallel pilot-scale integrated constructed wetland (ICW) systems were operated for one year. Each ICW consisted of a down-flow bed, an up-flow bed and a horizontal subsurface flow bed. The average removal rates of chemical oxygen demand (CODCr), total suspended solids (TSS), ammonia (NH4(+)-N), total nitrogen (TN) and total phosphorus (TP) were 63.6, 91.9, 38.7, 43.0 and 70.0%, respectively, and the corresponding amounts of pollutant retention were approximately 368.3, 284.9, 23.2, 44.6 and 5.9 g m(-2) yr(-1), respectively. High hydraulic loading rate (HLR) of 200 mm/d and low water temperatures (<15 °C) resulted in significant decrease in removals for TP and NH4(+)-N, but had no significant effects on removals of COD and TSS. These results indicated that the operation of this ICW at higher HLR (200 mm/d) might be effective and feasible for TSS and COD removal, but for acceptable removal efficiencies of nitrogen and phosphorus it should be operated at lower HLR (100 mm/d). This kind of ICW could be employed as an effective technique for SRS treatment.

  3. Productivity and injectivity of horizontal wells

    SciTech Connect

    Aziz, Khalid

    2000-03-06

    One of the key issues addressed was pressure drop in long horizontal wells and its influence on well performance. Very little information is available in the literature on flow in pipes with influx through pipe walls. Virtually all of this work has been in small diameter pipes and with single-phase flow. In order to address this problem new experimental data on flow in horizontal and near horizontal wells have been obtained. Experiments were conducted at an industrial facility on typical 6 1/8 ID, 100 feet long horizontal well model. The new data along with available information in the literature have been used to develop new correlations and mechanistic models. Thus it is now possible to predict, within reasonable accuracy, the effect of influx through the well on pressure drop in the well.

  4. Localization of subsurface fluorescent lesions using surface spectral measurements

    NASA Astrophysics Data System (ADS)

    Kolste, Kolbein

    Localization of Subsurface Fluorescent Lesions using Surface Spectral Measurements Sponsored by the National Institute of Health, Bethesda, Maryland Kolbein Kolste, Ph.D. Keith Paulsen In neurosurgical tumor resection, maximizing extent of resection plays a major role in the care of cancer patients. To date, ALA is being researched as a technique to guide tumor resection by inducing the accumulation of the endogenous fluorophore PpIX. Most research has focused on the use of blue light excitation of PpIX to visual the tumor. However, due to the high attenuation of blue light by in vivo chromophores, such as oxy- and deoxy-hemoglobin, the source of collected fluorescence emissions is confined to the top layer of cells, and the signal is subject to masking by blood on the surface of the surgical field of view. This issue is particularly a problem at the end of the resection, when the surgeon is evaluating the margin for remaining tumor, but the blue-signal is insensitive to residual tumor that may be located several millimeters beneath the surface. PpIX has an absorption band in the near infrared (NIR), where the absorption due to blood is orders of magnitude lower, enabling the excitation of a fluorophore at depth. In this work, we created a hyperspectral imaging system that attaches to a neurosurgical microscope and is capable of detecting PpIX fluorescence that has been excited at 635 nm. We utilize a dual-waveband technique from the hyperspectral to estimate depth of fluorescence origin and characterize the inherent limitations of the estimated depth. One of the major benefits of this technique is that the estimation is independent of the concentration and size of the fluorophore. This is first demonstrated in phantom studies, where the depths of multiple separate inclusions at various depths are accurately estimated. The technique is verified in animal tumor models and translated into the clinical theater, with pilot data showing the first estimation of depth of

  5. Subsurface Flow and Transport: A Stochastic Approach

    NASA Astrophysics Data System (ADS)

    Desbarats, Alexandre

    Anyone who has examined core or petrophysical logs from well bores has wondered at the rhythmic successions of sedimentary fades and has puzzled at their sudden disruption or reappearance. Such wonderment is no doubt shared by those who have stood at a quarry face gazing up at the intricate hierarchy of depositional patterns and the varied textures of sediments. A fortunate few have even slogged along a mine drift and observed at close hand the perplexing relationship between the geological fabric of a rock mass and occurrences of groundwater inflow. Happily, the heterogeneity of geological materials is now widely recognized and efforts over the last 20 years have been concerned with its incorporation into models of fluid flow and solute transport in the subsurface. These research efforts are, at least in part, driven by acute societal concerns over the contamination of groundwater resources and proposed plans for the disposal of nuclear and other toxic wastes in the subsurface.

  6. Microbial methanogenesis in subsurface oil and coal.

    PubMed

    Meslé, Margaux; Dromart, Gilles; Oger, Philippe

    2013-11-01

    It is now clear that active methanogens are present in the deep-subsurface. This paper reviews microbial population structures and the biodegradation of organic compounds to methane in situ within oil reservoirs and coal deposits. It summarizes our current knowledge of methanogenes and methanogenesis, fermenters, synthrophs and microbial metabolism of complex organic compounds in these two widely occurring organic-rich subsurface environments. This review is not intended to be an exhaustive report of microbial diversity. Rather, it illustrates the similarities and differences between the two environments with specific examples, from the nature of the organic molecules to the methanogenic metabolic pathways and the structure of the microbial populations to demonstrate that widely diverging microbial populations show surprisingly similar metabolic capabilities.

  7. Modeling gas transport in the Martian subsurface

    NASA Astrophysics Data System (ADS)

    Gloesener, Elodie; Karatekin, Özgür; Dehant, Véronique

    2015-04-01

    Modeling gas transport through Martian subsurface and outgassing processes is essential in the study of atmospheric evolution of Mars. We present an overview of gas transport in Martian soil focusing on water vapor and methane diffusion to explain the recent observations of methane in Martian atmosphere with a diffusive transport model. The range of parameters that have the largest effect on transport in Martian conditions is investigated. Among the possible sources of methane, clathrate hydrates destabilization is one potential mechanism. Hydrate stability zone in subsurface is also investigated. In 2016, ExoMars Trace Gas Orbiter (TGO) will have the capabilities to detect and characterize trace gases in Martian atmosphere and will bring additional information to validate the different possible outgassing scenarios.

  8. Spreadsheet log analysis in subsurface geology

    USGS Publications Warehouse

    Doveton, J.H.

    2000-01-01

    Most of the direct knowledge of the geology of the subsurface is gained from the examination of core and drill-cuttings recovered from boreholes drilled by the petroleum and water industries. Wireline logs run in these same boreholes generally have been restricted to tasks of lithostratigraphic correlation and thee location of hydrocarbon pay zones. However, the range of petrophysical measurements has expanded markedly in recent years, so that log traces now can be transformed to estimates of rock composition. Increasingly, logs are available in a digital format that can be read easily by a desktop computer and processed by simple spreadsheet software methods. Taken together, these developments offer accessible tools for new insights into subsurface geology that complement the traditional, but limited, sources of core and cutting observations.

  9. Pilot-Scale Demonstration of In-Situ Chemical Oxidation Involving Chlorinated Volatile Organic Compounds - Design and Deployment Guidelines (Parris Island, SC, U.S. Marine Corp Recruit Depot, Site 45 Pilot Study)

    EPA Science Inventory

    A pilot-scale in situ chemical oxidation (ISCO) demonstration, involving subsurface injections of sodium permanganate (NaMnO4), was performed at the US Marine Corp Recruit Depot (MCRD), site 45 (Parris Island (PI), SC). The ground water was originally contaminated with perchloroe...

  10. Horizontal sidetrack taps reservoir sweet spots''

    SciTech Connect

    Wible, J.R. )

    1994-02-21

    Cutting a window at 85[degree] deviation allowed a sidetrack to pass through the high-resistivity sections in a Gulf of Mexico reservoir. Results from logging-while-drilling (LWD) tools indicated the original horizontal bore dropped too low in the reservoir, possibly leading to a low productivity well. The subsequent sidetrack successfully delivered the desired well bore, and the increased productivity justified the efforts in cutting a window in the horizontal section.

  11. Report of the Horizontal Launch Study

    NASA Technical Reports Server (NTRS)

    Wilhite, Alan W.; Bartolotta, Paul A.

    2011-01-01

    A study of horizontal launch concepts has been conducted. This study, jointly sponsored by the Defense Advanced Research Projects Agency (DARPA) and the National Aeronautics and Space Administration (NASA) was tasked to estimate the economic and technical viability of horizontal launch approaches. The study team identified the key parameters and critical technologies which determine mission viability and reported on the state of the art of critical technologies, along with objectives for technology development.

  12. Spatiotemporal variability in peatland subsurface methane dynamics

    NASA Astrophysics Data System (ADS)

    Strack, M.; Waddington, J. M.

    2008-06-01

    Peatlands are large natural sources of atmospheric methane (CH4). While many studies have measured CH4 emissions to the atmosphere, less is known about the stock and residence time of subsurface CH4. In this study we examined dissolved CH4 concentration in near-surface peatland pore waters of a poor fen near Québec City, Canada, in order to (1) investigate the variability in and potential controls on these concentrations and (2) combine measured dissolved CH4 concentration with estimated bubble CH4 stock and measured CH4 fluxes to estimate the mean residence time of subsurface CH4. Concentrations ranged from 1 to 450 μM during both study seasons. Depth profiles were generally consistent at one location within the peatland throughout the sampling period but varied between locations. Patterns with depth were not well correlated to pore water pH or EC; however, changes in CH4 concentration through time in the upper 30 cm were related to temperature and water table at some locations. Depth profiles taken at 2- to 5-cm intervals revealed discrete concentration "spikes" which were often maintained throughout the season and are likely related to bubble CH4 dynamics. Estimated subsurface CH4 stocks indicate that even when relatively low bubble volume (5% of peat volume) is assumed, bubble CH4 accounted for greater than half of total stocks. Calculated mean residence times were 28-120 days. This implies that CH4 flux may lag changes in water table and temperature which happen on shorter timescales (hours or days). To improve our description of subsurface CH4 stocks, links between dissolved and bubble CH4 stocks and peatland CH4 residence time, coincident measurement of pore water CH4 concentrations, entrapped gas content and composition, diffusive CH4 flux, and ebullition are required.

  13. Drill Embedded Nanosensors For Planetary Subsurface Exploration

    NASA Technical Reports Server (NTRS)

    Li, Jing

    2014-01-01

    We have developed a carbon nanotube (CNT) sensor for water vapor detection under Martian Conditions and the miniaturized electronics can be embedded in the drill bit for collecting sensor data and transmit it to a computer wirelessly.This capability will enable the real time measurement of ice during drilling. With this real time and in-situ measurement, subsurface ice detection can be easy, fast, precise and low cost.

  14. Subsurface materials management and containment system

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2006-10-17

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  15. Subsurface materials management and containment system

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kosteinik, Kevin M.; Sloan, Paul A.

    2004-07-06

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  16. Metalliferous Biosignatures for Deep Subsurface Microbial Activity

    NASA Astrophysics Data System (ADS)

    Parnell, John; Brolly, Connor; Spinks, Sam; Bowden, Stephen

    2016-03-01

    The interaction of microbes and metals is widely assumed to have occurred in surface or very shallow subsurface environments. However new evidence suggests that much microbial activity occurs in the deep subsurface. Fluvial, lacustrine and aeolian `red beds' contain widespread centimetre-scale reduction spheroids in which a pale reduced spheroid in otherwise red rocks contains a metalliferous core. Most of the reduction of Fe (III) in sediments is caused by Fe (III) reducing bacteria. They have the potential to reduce a range of metals and metalloids, including V, Cu, Mo, U and Se, by substituting them for Fe (III) as electron acceptors, which are all elements common in reduction spheroids. The spheroidal morphology indicates that they were formed at depth, after compaction, which is consistent with a microbial formation. Given that the consequences of Fe (III) reduction have a visual expression, they are potential biosignatures during exploration of the terrestrial and extraterrestrial geological record. There is debate about the energy available from Fe (III) reduction on Mars, but the abundance of iron in Martian soils makes it one of the most valuable prospects for life there. Entrapment of the microbes themselves as fossils is possible, but a more realistic target during the exploration of Mars would be the colour contrasts reflecting selective reduction or oxidation. This can be achieved by analysing quartz grains across a reduction spheroid using Raman spectroscopy, which demonstrates its suitability for life detection in subsurface environments. Microbial action is the most suitable explanation for the formation of reduction spheroids and may act as metalliferous biosignatures for deep subsurface microbial activity.

  17. Radionuclide Sensors for Subsurface Water Monitoring

    SciTech Connect

    Timothy DeVol

    2006-06-30

    Contamination of the subsurface by radionuclides is a persistent and vexing problem for the Department of Energy. These radionuclides must be measured in field studies and monitoed in the long term when they cannot be removed. However, no radionuclide sensors existed for groundwater monitoring prior to this team's research under the EMSP program Detection of a and b decays from radionuclides in water is difficult due to their short ranges in condensed media.

  18. Low Cost, Low Power, Passive Muon Telescope For Interrogating Martian Sub-Surface

    NASA Astrophysics Data System (ADS)

    Naudet, C. J.; Tanaka, H.; Kedar, S.; Plaut, J. J.; Webb, F.

    2012-12-01

    Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of geological structures in much the same way as standard X-ray radiography. Unlike gamma rays and neutrons that penetrate only a few meters of rock, muons can traverse through up to several kilometers of a geological target. Recent development and application of the technique to terrestrial volcanoes, caves, and mines have demonstrated that a low-power, passive muon detector can image deep into kilometer-scale geological structures and provide unprecedentedly crisp density profile images of their interior. Preliminary estimates of muon production on Mars indicate that the near-horizontal Martian mu-on flux, which is used for muon radiography of surface features, is at least as strong as that on Earth, making the technique suitable for geological exploration of Mars. The muon telescope represents an entirely new class of instruments for planetary exploration, providing a wholly new type of measurement for delineation of potentially habitable subsurface environments through detection of caves, sub-surface ice, and water, and for the interpretation of composition and evolutionary state of the Martian surface. Muon radiography is a proven, sim-ple, low cost, and efficient technology that could detect subsurface radiation-shielded habitable environments that would not be detectable by any other technique available today. Thanks to its low power and low data rate demands, it could be integrated as a secondary instrument on future missions with minimal impact on primary mission operations. A mission that includes a muon detector could set the stage for a future mission to directly explore subsurface habitable envi-ronments on Mars. Developing the technology now would position it favorably for a surface mission in the 2018-2024 time period to explore Martian regions with previously-identified po-tential trace gas sources

  19. Emotion recognition (sometimes) depends on horizontal orientations

    PubMed Central

    Huynh, Carol M; Balas, Benjamin

    2014-01-01

    Face recognition depends critically on horizontal orientations (Goffaux & Dakin, 2010). Face images that lack horizontal features are harder to recognize than those that have that information preserved. Presently, we asked if facial emotional recognition also exhibits this dependency by asking observers to categorize orientation-filtered happy and sad expressions. Furthermore, we aimed to dissociate image-based orientation energy from object-based orientation by rotating images 90-degrees in the picture-plane. In our first experiment, we showed that the perception of emotional expression does depend on horizontal orientations and that object-based orientation constrained performance more than image-based orientation. In Experiment 2 we showed that mouth openness (i.e. open versus closed-mouths) also influenced the emotion-dependent reliance on horizontal information. Lastly, we describe a simple computational analysis that demonstrates that the impact of mouth openness was not predicted by variation in the distribution of orientation energy across horizontal and vertical orientation bands. Overall, our results suggest that emotion recognition does largely depend on horizontal information defined relative to the face, but that this bias is modulated by multiple factors that introduce variation in appearance across and within distinct emotions. PMID:24664854

  20. Activation of Peroxymonosulfate by Subsurface Minerals

    NASA Astrophysics Data System (ADS)

    Yu, Miao; Teel, Amy L.; Watts, Richard J.

    2016-08-01

    In situ chemical oxidation (ISCO) has become a widely used technology for the remediation of soil and groundwater. Although peroxymonosulfate is not a common oxidant source for ISCO, its chemical structure is similar to the ISCO reagents hydrogen peroxide and persulfate, suggesting that peroxymonosulfate may have the beneficial properties of each of these oxidants. Peroxymonosulfate activation in the presence of subsurface minerals was examined as a basis for ISCO, and possible reactive species (hydroxyl radical, sulfate radical, and reductants + nucleophiles) generated in the mineral-activated peroxymonosulfate systems were investigated. Rates of peroxymonosulfate decomposition and generation rates of reactive species were studied in the presence of three iron oxides, one manganese oxide, and three soil fractions. The iron oxide hematite-activated peroxymonosulfate system most effectively degraded the hydroxyl radical probe nitrobenzene. Reductants + nucleophiles were not generated in mineral-activated peroxymonosulfate systems. Use of the probe compound anisole in conjunction with scavengers demonstrated that both sulfate radical and hydroxyl radical are generated in mineral-activated peroxymonosulfate systems. In order to confirm the activation of peroxymonosulfate by subsurface minerals, one natural soil and associated two soil fractions were evaluated as peroxymonosulfate catalysts. The natural soil did not effectively promote the generation of oxidants; however, the soil organic matter was found to promote the generation of reductants + nucleophiles. The results of this research show that peroxymonosulfate has potential as an oxidant source for ISCO applications, and would be most effective in treating halogenated contaminants when soil organic matter is present in the subsurface.

  1. Subsurface heat flow in an urban environment

    NASA Astrophysics Data System (ADS)

    Ferguson, Grant; Woodbury, Allan D.

    2004-02-01

    The subsurface temperature field beneath Winnipeg, Canada, is significantly different from that of the surrounding rural areas. Downward heat flow to depths as great as 130 m has been noted in some areas beneath the city and groundwater temperatures in a regional aquifer have risen by as much as 5°C in some areas. Numerical simulation of heat transport supports the conjecture that these temperature changes can be largely attributed to heat loss from buildings and the temperature at any given point is sensitive to the distance from and the age of any buildings. The effect is most noticable when buildings are closely spaced, which is typical of urban areas. Temperature measurements in areas more than a few hundred meters away from any heated structure were only a few tenths of a degree Celsius greater than those observed outside the city, suggesting that other reasons for increases in subsurface temperature, such as changes in surface cover or climate change, may be responsible for some of the some of the observed increase in temperatures. These sources of additional heat to the subsurface make it difficult to resolve information on past climates from temperatures measured in boreholes and monitoring wells. In some areas, the temperature increases may also have an impact on geothermal energy resources. This impact might be in the form of an increase in heat pump efficiency or in the case of the Winnipeg area, a decrease in the efficiency of direct use of groundwater for cooling.

  2. Hydrogen Utilization Potential in Subsurface Sediments.

    PubMed

    Adhikari, Rishi R; Glombitza, Clemens; Nickel, Julia C; Anderson, Chloe H; Dunlea, Ann G; Spivack, Arthur J; Murray, Richard W; D'Hondt, Steven; Kallmeyer, Jens

    2016-01-01

    Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H2ases to successively higher concentrations of H2 in successively deeper zones.

  3. Chemical inversion in the subsurface hydrosphere

    SciTech Connect

    Yezhov, Yu.A.

    1980-09-01

    A quite common nature of chemical inversion in subsurface hydrosphere is shown in examples of several oil- and gas-bearing regions of the USSR. In particular, when the data of sampling from deep wells of the Volgo-Urals, Mangyshlak, and Western Turkmenian regions were compared, it became obvious that the composite chemical profile of subsurface hydrosphere consists of a vertical alternation of three zones: of increasing (I-II-IIIa genetic types of subsurface waters), maximum (IIIb), and decreasing water mineralization (III'a-II'-I'). The depth of occurrence of the lower inversion branch of zonality depends on the geotectonic activity at depth. It is closer to the Earth's surface in regions of Alpine tectogenesis, whereas in regions of ancient folding it lies at great depths which have not yet been reached by most deep wells. The formation of the inversion zone in the Earth's crust is connected with penetration from below ascending demineralized fluids of sodium bicarbonate type (I'). The latter is due to the presence at great depths of large quantities of free carbonic acid which is involved in hydrolytic processes of decomposition of sodium-containing minerals and produces sodium-type waters.

  4. Resonant seismic emission of subsurface objects

    SciTech Connect

    Korneev, Valeri A.

    2009-04-15

    Numerical modeling results and field data indicate that some contrasting subsurface objects (such as tunnels, caves, pipes, filled pits, and fluid-filled fractures) are capable of generating durable resonant oscillations after trapping seismic energy. These oscillations consist of surface types of circumferential waves that repeatedly propagate around the object. The resonant emission of such trapped energy occurs primarily in the form of shear body waves that can be detected by remotely placed receivers. Resonant emission reveals itself in the form of sharp resonant peaks for the late parts of the records, when all strong direct and primary reflected waves are gone. These peaks were observed in field data for a buried barrel filled with water, in 2D finite-difference modeling results, and in the exact canonical solution for a fluid-filled sphere. A computed animation for the diffraction of a plane wave upon a low-velocity elastic sphere confirms the generation of resonances by durable surface waves. Resonant emission has characteristic quasi-hyperbolic traveltime patterns on shot gathers. The inversion of these patterns can be performed in the frequency domain after muting the strong direct and primary scattered waves. Subsurface objects can be detected and imaged at a single resonance frequency without an accurate knowledge of source trigger time. The imaging of subsurface objects requires information about the shear velocity distribution in an embedding medium, which can be done interactively during inversion.

  5. Subsurface barrier integrity verification using perfluorocarbon tracers

    SciTech Connect

    Sullivan, T.M.; Heiser, J.; Milian, L.; Senum, G.

    1996-12-01

    Subsurface barriers are an extremely promising remediation option to many waste management problems. Gas phase tracers include perfluorocarbon tracers (PFT`s) and chlorofluorocarbon tracers (CFC`s). Both have been applied for leak detection in subsurface systems. The focus of this report is to describe the barrier verification tests conducted using PFT`s and analysis of the data from the tests. PFT verification tests have been performed on a simulated waste pit at the Hanford Geotechnical facility and on an actual waste pit at Brookhaven National Laboratory (BNL). The objective of these tests were to demonstrate the proof-of-concept that PFT technology can be used to determine if small breaches form in the barrier and for estimating the effectiveness of the barrier in preventing migration of the gas tracer to the monitoring wells. The subsurface barrier systems created at Hanford and BNL are described. The experimental results and the analysis of the data follow. Based on the findings of this study, conclusions are offered and suggestions for future work are presented.

  6. Hydrogen Utilization Potential in Subsurface Sediments

    PubMed Central

    Adhikari, Rishi R.; Glombitza, Clemens; Nickel, Julia C.; Anderson, Chloe H.; Dunlea, Ann G.; Spivack, Arthur J.; Murray, Richard W.; D'Hondt, Steven; Kallmeyer, Jens

    2016-01-01

    Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H2ases to successively higher concentrations of H2 in successively deeper zones. PMID:26858697

  7. Subsurface urban heat islands in German cities.

    PubMed

    Menberg, Kathrin; Bayer, Peter; Zosseder, Kai; Rumohr, Sven; Blum, Philipp

    2013-01-01

    Little is known about the intensity and extension of subsurface urban heat islands (UHI), and the individual role of the driving factors has not been revealed either. In this study, we compare groundwater temperatures in shallow aquifers beneath six German cities of different size (Berlin, Munich, Cologne, Frankfurt, Karlsruhe and Darmstadt). It is revealed that hotspots of up to +20K often exist, which stem from very local heat sources, such as insufficiently insulated power plants, landfills or open geothermal systems. When visualizing the regional conditions in isotherm maps, mostly a concentric picture is found with the highest temperatures in the city centers. This reflects the long-term accumulation of thermal energy over several centuries and the interplay of various factors, particularly in heat loss from basements, elevated ground surface temperatures (GST) and subsurface infrastructure. As a primary indicator to quantify and compare large-scale UHI intensity the 10-90%-quantile range UHII(10-90) of the temperature distribution is introduced. The latter reveals, in comparison to annual atmospheric UHI intensities, an even more pronounced heating of the shallow subsurface.

  8. Comparing the efficiency of Cyperus alternifolius and Phragmites australis in municipal wastewater treatment by subsurface constructed wetland.

    PubMed

    Shahi, Davod Hossein; Eslami, Hadi; Ehrampoosh, Mohamad Hasan; Ebrahimi, Asghar; Ghaneian, Mohamad Taghy; Ayatollah, Shirin; Mozayan, Mohamad Reza

    2013-04-15

    Nowadays, application of natural wastewater treatment systems such as wetland not only reduces economic costs and energy consumption, but also decreases environmental pollution. This study aimed to compare efficiency of Cyperus alternifolius and Phragmites australis in Municipal wastewater treatment by Subsurface Constructed Wetland Method. This is an applied-interventionnal study in which three reactors (control pilot, Cyperus alternifolius (umbrella palm) plant pilot and Phragmites australis (reed) plant pilot were designed by subsurface constructed wetland method. Then 90 samples were taken from input and output of reactors with four-day retention time. These samples were tested and finally the data were analyzed by Paired Sample Test statistical analysis. The results showed that removal efficiency of the parameters such as COD, BOD5, TSS, NO3-N, NH3-N, PO4-P, total coliform and fecal coliform was 74, 73, 84, 40, 36, 70, 33 and 38% in Cyperus alternifolius plant wetland, 44, 34, 77, 15, 0.3, 1, 17 and 26% in control wetland and 59, 54, 73, 6, 3, 10, 93 and 50 in Phragmites australis plant wetland, respectively. This reduction rate in all parameters- except fecal coliform- was statistically significant (p = 0.05). The results of this study showed that Cyperus alternifolius plant had higher efficiency in the removal of chemical parameters, whereas Phragmites australis plant had appropriate efficiency in the removal of microbiological parameters. Therefore, it can be concluded that application of these two plants can be effective in wastewater treatment.

  9. Horizontal distribution of Fukushima-derived radiocesium in zooplankton in the northwestern Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Kitamura, M.; Kumamoto, Y.; Kawakami, H.; Cruz, E. C.; Fujikura, K.

    2013-04-01

    The magnitude of the 9.0 Tohoku earthquake and the ensuing tsunami on 11 March 2011, inflicted heavy damage on the Fukushima Dai-ichi nuclear power plant (FNPP1). Fission products were emitted, falling over a broad range in the northern hemisphere, and water contaminated with radionuclides leaked into the ocean. In this study, we described the horizontal distribution of the Fukushima-derived radiocesium in zooplankton and in seawater in the western North Pacific Ocean (500-2100 km from the FNPP1) 10 months after the accident. 134Cs and 137Cs were detected in zooplankton and seawater from all the stations. Because of its short half-lives, 134Cs detected in our samples could only be derived from the FNPP1 accident. The highest 137Cs activity in zooplankton was same order of magnitude as that one month after the accident, and average activity was one or two orders of magnitude higher than 137Cs activities observed before the accident around Japan. Horizontally, the radiocesium activity concentrations in zooplankton were high at around 25° N while those in surface seawater were high at around the transition area between the Kuroshio and the Oyashio Currents (36-40° N). We observed subsurface radiocesium maxima in density range of the North Pacific Subtropical Mode Water and occurrence of many diel vertical migratory zooplanktons. These suggested that the high activity concentrations in the subtropical zooplankton at around 25° N were connected to the subsurface radiocesium and active vertical migration of zooplankton. However, the high activity concentrations of radiocesium in subsurface seawater did not necessarily follow the higher radiocesium activity in zooplankton. Biological characteristics of zooplankton community possibly influenced how large was contamination of radiocesium in the community but it is still unknown what kind of biological factors were important.

  10. Horizontal distribution of Fukushima-derived radiocesium in zooplankton in the northwestern Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Kitamura, M.; Kumamoto, Y.; Kawakami, H.; Cruz, E. C.; Fujikura, K.

    2013-08-01

    The magnitude of the 9.0 Tohoku earthquake and the ensuing tsunami on 11 March 2011, inflicted heavy damage on the Fukushima Dai-ichi nuclear power plant (FNPP1). Fission products were emitted, falling over a broad range in the Northern Hemisphere, and water contaminated with radionuclides leaked into the ocean. In this study, we described the horizontal distribution of the Fukushima-derived radiocesium in zooplankton and in seawater in the western North Pacific Ocean (500-2100 km from the FNPP1) 10 months after the accident. 134Cs and 137Cs were detected in zooplankton and seawater from all the stations. Because of its short half-life, the 134Cs detected in our samples could only be derived from the FNPP1 accident. The highest 137Cs activity in zooplankton was the same order of magnitude as it was one month after the accident, and average activity was one or two orders of magnitude higher than 137Cs activities observed before the accident around Japan. Horizontally, the radiocesium activity concentrations in zooplankton were high at around 25° N while those in surface seawater were high at around the transition area between the Kuroshio and the Oyashio currents (36-40° N). We observed subsurface radiocesium maxima in density range of the North Pacific Subtropical Mode Water and the occurrence of many diel vertical migratory zooplankton. These suggested that the high activity concentrations in the subtropical zooplankton at around 25° N were connected to the subsurface radiocesium and active vertical migration of zooplankton. However, the high activity concentrations of radiocesium in subsurface seawater did not necessarily correlate with the higher radiocesium activity in zooplankton. Activity concentrations of radiocesium in zooplankton might be influenced not only by the environmental radiocesium activity concentrations but also by other factors, which are still unknown.

  11. 76 FR 54095 - Pilot in Command Proficiency Check and Other Changes to the Pilot and Pilot School Certification...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-31

    ...This final rule amends the FAA's regulations concerning pilot, flight instructor, and pilot school certification. This rule will require pilot-in-command (PIC) proficiency checks for pilots who act as PIC of turbojet-powered aircraft except for pilots of single seat experimental jets and pilots of experimental jets who do not carry passengers. It allows pilot applicants to apply concurrently......

  12. 14 CFR 61.94 - Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Student pilot seeking a sport pilot... Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations at... operational control tower in other airspace. (a) A student pilot seeking a sport pilot certificate or...

  13. 14 CFR 61.94 - Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Student pilot seeking a sport pilot... Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations at... operational control tower in other airspace. (a) A student pilot seeking a sport pilot certificate or...

  14. 14 CFR 61.94 - Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Student pilot seeking a sport pilot... Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations at... operational control tower in other airspace. (a) A student pilot seeking a sport pilot certificate or...

  15. 14 CFR 61.94 - Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Student pilot seeking a sport pilot... Student pilot seeking a sport pilot certificate or a recreational pilot certificate: Operations at... operational control tower in other airspace. (a) A student pilot seeking a sport pilot certificate or...

  16. Reactive transport benchmarks for subsurface environmental simulation

    SciTech Connect

    Steefel, Carl I.; Yabusaki, Steven B.; Mayer, K. U.

    2015-06-01

    Over the last 20 years, we have seen firsthand the evolution of multicomponent reactive transport modeling and the expanding range and increasing complexity of subsurface applications it is being used to address. There is a growing reliance on reactive transport modeling (RTM) to address some of the most compelling issues facing our planet: climate change, nuclear waste management, contaminant remediation, and pollution prevention. While these issues are motivating the development of new and improved capabilities for subsurface environmental modeling using RTM (e.g., biogeochemistry from cell-scale physiology to continental-scale terrestrial ecosystems, nonisothermal multiphase conditions, coupled geomechanics), there remain longstanding challenges in characterizing the natural variability of hydrological, biological, and geochemical properties in subsurface environments and limited success in transferring models between sites and across scales. An equally important trend over the last 20 years is the evolution of modeling from a service sought out after data has been collected to a multifaceted research approach that provides (1) an organizing principle for characterization and monitoring activities; (2) a systematic framework for identifying knowledge gaps, developing and integrating new knowledge; and (3) a mechanistic understanding that represents the collective wisdom of the participating scientists and engineers. There are now large multidisciplinary projects where the research approach is model-driven, and the principal product is a holistic predictive simulation capability that can be used as a test bed for alternative conceptualizations of processes, properties, and conditions. Much of the future growth and expanded role for RTM will depend on its continued ability to exploit technological advancements in the earth and environmental sciences. Advances in measurement technology, particularly in molecular biology (genomics), isotope fractionation, and high

  17. Theoretical and experimental investigations of ferrofluids for guiding and detecting liquids in the subsurface. FY 1997 annual report

    SciTech Connect

    Moridis, G.J.; Borglin, S.E.; Oldenburg, C.M.; Becker, A.

    1998-03-01

    Ferrofluids are stable colloidal suspensions of magnetic particles in various carrier liquids with high saturation magnetizations, which can be manipulated in virtually any fashion, defying gravitational or viscous forces in response to external magnetic fields. In this report, the authors review the results of their investigation of the potential of ferrofluids (1) to accurately and effectively guide reactants (for in-situ treatment) or barrier liquids (low-viscosity permeation grouts) to contaminated target zones in the subsurface using electromagnetic forces, and (2) to trace the movement and position of liquids injected in the subsurface using geophysical methods. They investigate the use of ferrofluids to enhance the efficiency of in-situ treatment and waste containment through (a) accurate guidance and delivery of reagent liquids to the desired subsurface contamination targets and/or (b) effective sweeping of the contaminated zone as ferrofluids move from the application point to an attracting magnet/collection point. They also investigate exploiting the strong magnetic signature of ferrofluids to develop a method for monitoring of liquid movement and position during injection using electromagnetic methods. The authors demonstrated the ability to induce ferrofluid movement in response to a magnetic field, and measured the corresponding magnetopressure. They demonstrated the feasibility of using conventional magnetometry for detecting subsurface zones of various shapes containing ferrofluids for tracing liquids injected for remediation or barrier formation. Experiments involving spherical, cylindrical and horizontal slabs showed a very good agreement between predictions and measurements.

  18. Pilot Weather Advisor System

    NASA Technical Reports Server (NTRS)

    Lindamood, Glenn; Martzaklis, Konstantinos Gus; Hoffler, Keith; Hill, Damon; Mehrotra, Sudhir C.; White, E. Richard; Fisher, Bruce D.; Crabill, Norman L.; Tucholski, Allen D.

    2006-01-01

    The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understand

  19. Pilot weather advisor

    NASA Technical Reports Server (NTRS)

    Kilgore, W. A.; Seth, S.; Crabill, N. L.; Shipley, S. T.; Graffman, I.; Oneill, J.

    1992-01-01

    The results of the work performed by ViGYAN, Inc., to demonstrate the Pilot Weather Advisor cockpit weather data system using a broadcast satellite communication system are presented. The Pilot Weather Advisor demonstrated that the technical problems involved with transmitting significant amount of weather data to an aircraft in-flight or on-the-ground via satellite are solvable with today's technology. The Pilot Weather Advisor appears to be a viable solution for providing accurate and timely weather information for general aviation aircraft.

  20. Horizontal oil shale and tar sands retort

    SciTech Connect

    Thomas, D.D.

    1982-08-31

    A horizontal retorting apparatus and method are disclosed designed to pyrolyze tar sands and oil shale, which are often found together in naturally occurring deposits. The retort is based on a horizontal retorting tube defining a horizontal retort zone having an upstream and a downstream end. Inlet means are provided for introducing the combined tar sands and oil shale into the upstream end of the retort. A screw conveyor horizontally conveys tar sands and oil shale from the upstream end of the retort zone to the downstream end of the retort zone while simultaneously mixing the tar sands and oil shale to insure full release of product gases. A firebox defining a heating zone surrounds the horizontal retort is provided for heating the tar sands and oil shale to pyrolysis temperatures. Spent shale and tar sands residue are passed horizontally beneath the retort tube with any carbonaceous residue thereon being combusted to provide a portion of the heat necessary for pyrolysis. Hot waste solids resulting from combustion of spent shale and tar sands residue are also passed horizontally beneath the retort tube whereby residual heat is radiated upward to provide a portion of the pyrolysis heat. Hot gas inlet holes are provided in the retort tube so that a portion of the hot gases produced in the heating zone are passed into the retort zone for contacting and directly heating the tar sands and oil shale. Auxiliary heating means are provided to supplement the heat generated from spent shale and tar sands residue combustion in order to insure adequate pyrolysis of the raw materials with varying residual carbonaceous material.

  1. Subsidence related horizontal earth movements in the Tia Juana field, State of Zulia, Venezuela

    SciTech Connect

    Scherer, W.F.; Pedroza, M.A. )

    1990-05-01

    Subsidence due to oil exploitation in the Bolivar Coast fields in western Venezuela has been monitored since 1926. Related horizontal earth movements have been measured by geodetic methods during the last 10 yr in the northern Tia Juana field area in and around the Ule tank farm and the GLP gas liquefaction plant. Damage to storage tanks and increasing appearance of fractures in the ground in the vicinity of the coastal dyke protection system warranted a detailed study. A surface geologic survey of the Ule area, based initially on aerophotographic interpretation of infrared photographs, flown, on a 1:5,000 scale, showed the area to be divided into blocks by several major faults. These faults were confirmed on the ground by visual inspection, shallow seismic refraction, geoelectric surveys and correlation of geotechnical borings. A geodetic survey of the area with a precision of 5 mm + 2 mm/km for distances, showed significant horizontal displacements of ground markers during an eight-year period. Accordingly, a measuring plan of high-precision (0.015 mm) electromechanic extensometer lines was designed for critical zones across known fault traces and fracture zones. A conceptual model integrates geodetic and extensometer measurements of horizontal movements in the Ule area with the geologic and neotectonic frame of subsurface faults, joining systems, and tensional surface cracks. Rates of Holocene postglacial isostatic adjustments and natural, pre-industry subsidence due to degassing of reservoirs determined by C{sup 14} radiocarbon dating, were used to calculate subsidence rates due to oil exploitation. It was found that the subsidence occurs in the area, not as previously mapped continuous function of compaction, but as discrete, fault and crack limited blocks, governed as much by reactivation of fault slippage as by subsurface compaction.

  2. How to drill horizontal sections faster

    SciTech Connect

    Chaffin, M. )

    1991-12-01

    This paper reports that fewer trips, reduced slide time and lower drag during sliding have resulted from the application of downhole-adjustable stabilizers to horizontal drilling. Faster drilling times mean lower measurement while drilling (MWD) cost, and less wear on downhole equipment, motors and bits. These advantages combined with reduced drilling shocks have increased drilling rates and efficiency. Applying existing technology in new situations is an important way of reducing the cost of finding, exploring for and developing reserves. Engineers are responsible for using current technology to its fullest and developing new technology to reduce drilling expenses. Horizontal drilling was used in its early stages to develop the Austin chalk formation in Pearsall oil field more effectively. As procedures were generated to drill horizontal wells, Oryx drilling engineers began to develop new technology and investigate ways for existing technology to be used or altered to fit horizontal drilling programs. The new technology of downhole-adjustable stabilizers has been used successfully to further improve horizontal drilling efficiency.

  3. Automated Pilot Advisory System

    NASA Technical Reports Server (NTRS)

    Parks, J. L., Jr.; Haidt, J. G.

    1981-01-01

    An Automated Pilot Advisory System (APAS) was developed and operationally tested to demonstrate the concept that low cost automated systems can provide air traffic and aviation weather advisory information at high density uncontrolled airports. The system was designed to enhance the see and be seen rule of flight, and pilots who used the system preferred it over the self announcement system presently used at uncontrolled airports.

  4. Subsurface Tectonics and Pingos of Northern Alaska

    NASA Astrophysics Data System (ADS)

    Skirvin, S.; Casavant, R.; Burr, D.

    2008-12-01

    We describe preliminary results of a two-phase study that investigated links between subsurface structural and stratigraphic controls, and distribution of hydrostatic pingos on the central coastal plain of Arctic Alaska. Our 2300 km2 study area is underlain by a complete petroleum system that supports gas, oil and water production from 3 of the largest oil fields in North America. In addition, gas hydrate deposits exist in this area within and just below the permafrost interval at depths of 600 to 1800 feet below sea level. Phase 1 of the study compared locations of subsurface faults and pingos for evidence of linkages between faulting and pingo genesis and distribution. Several hundred discrete fault features were digitized from published data and georeferenced in a GIS database. Fault types were determined by geometry and sense of slip derived from well log and seismic maps. More than 200 pingos and surface sediment type associated with their locations were digitized from regional surficial geology maps within an area that included wire line and seismic data coverage. Beneath the pingos lies an assemblage of high-angle normal and transtensional faults that trend NNE and NW; subsidiary trends are EW and NNW. Quaternary fault reactivation is evidenced by faults that displaced strata at depths exceeding 3000 meters below sea level and intersect near-surface units. Unpublished seismic images and cross-section analysis support this interpretation. Kinematics and distribution of reactivated faults are linked to polyphase deformational history of the region that includes Mesozoic rift events, succeeded by crustal shortening and uplift of the Brooks Range to the south, and differential subsidence and segmentation of a related foreland basin margin beneath the study area. Upward fluid migration, a normal process in basin formation and fault reactivation, may play yet unrecognized roles in the genesis (e.g. fluid charging) of pingos and groundwater hydrology. Preliminary

  5. Recovery of bypassed oil in the Dundee Formation using horizontal drains. Quarterly report, July 1, 1996--September 30, 1996

    SciTech Connect

    Wood, J.R.

    1996-10-31

    The principal objective of this project is to demonstrate the feasibility and economic success of producing oil from abandoned or nearly abandoned fields in the Dundee Formation of Central Michigan using horizontal drilling technology. A site for a horizontal well was selected in Crystal Field, a nearly-abandoned Dundee oil field in Michigan. This field had produced over 8 million barrels of oil, mostly in the 1930`s and 1940`s. At the height of development, Crystal Field produced from 193 wells, but by 1995, only seven producing wells remained, each producing less than 10 bbls/day. A horizontal well was drilled as a field demonstration pilot, funded through this DOE project, and was immensely successful. Core and logs from the Dundee interval were recovered from a vertical borehole at the same surface location. The horizontal well was brought on production at a rate of 100 bbls/day and is probably capable of producing at a higher rate. The addition of several horizontal wells, similar to the demonstration well, will likely add another 2 million bbls (or more) to the cumulative production of the field over the next few years. The presence of untapped oil in this Dundee field was dramatically demonstrated and the favorable economics were made clearly evident. If other abandoned Dundee fields are re-developed in a similar manner, the additional oil produced could exceed 80 Trillion barrels. Horizontal drilling will likely revolutionize the development of old carbonate fields such as those in the Dundee of Michigan.

  6. Shallow Subsurface Structures of Volcanic Fissures

    NASA Astrophysics Data System (ADS)

    Parcheta, C. E.; Nash, J.; Mitchell, K. L.; Parness, A.

    2015-12-01

    Volcanic fissure vents are a difficult geologic feature to quantify. They are often too thin to document in detail with seismology or remote geophysical methods. Additionally, lava flows, lava drain back, or collapsed rampart blocks typically conceal a fissure's surface expression. For exposed fissures, quantifying the surface (let along sub0surface) geometric expression can become an overwhelming and time-consuming task given the non-uniform distribution of wall irregularities, drain back textures, and the larger scale sinuosity of the whole fissure system. We developed (and previously presented) VolcanoBot to acquire robust characteristic data of fissure geometries by going inside accessible fissures after an eruption ends and the fissure cools off to <50 C. Data from VolcanoBot documents the fissure conduit geometry with a near-IR structured light sensor, and reproduces the 3d structures to cm-scale accuracy. Here we present a comparison of shallow subsurface structures (<30 m depth) within the Mauna Ulu fissure system and their counterpart features at the vent-to-ground-surface interface. While we have not mapped enough length of the fissure to document sinuosity at depth, we see a self-similar pattern of irregularities on the fissure walls throughout the entire shallow subsurface, implying a fracture mechanical origin similar to faults. These irregularities are, on average, 1 m across and protrude 30 cm into the drained fissure. This is significantly larger than the 10% wall roughness addressed in the engineering literature on fluid dynamics, and implies that magma fluid dynamics during fissure eruptions are probably not as passive nor as simple as previously thought. In some locations, it is possible to match piercing points across the fissure walls, where the dike broke the wall rock in order to propagate upwards, yet in other locations there are erosional cavities, again, implying complex fluid dynamics in the shallow sub-surface during fissure eruptions.

  7. Noble gas fractionation during subsurface gas migration

    NASA Astrophysics Data System (ADS)

    Sathaye, Kiran J.; Larson, Toti E.; Hesse, Marc A.

    2016-09-01

    Environmental monitoring of shale gas production and geological carbon dioxide (CO2) storage requires identification of subsurface gas sources. Noble gases provide a powerful tool to distinguish different sources if the modifications of the gas composition during transport can be accounted for. Despite the recognition of compositional changes due to gas migration in the subsurface, the interpretation of geochemical data relies largely on zero-dimensional mixing and fractionation models. Here we present two-phase flow column experiments that demonstrate these changes. Water containing a dissolved noble gas is displaced by gas comprised of CO2 and argon. We observe a characteristic pattern of initial co-enrichment of noble gases from both phases in banks at the gas front, followed by a depletion of the dissolved noble gas. The enrichment of the co-injected noble gas is due to the dissolution of the more soluble major gas component, while the enrichment of the dissolved noble gas is due to stripping from the groundwater. These processes amount to chromatographic separations that occur during two-phase flow and can be predicted by the theory of gas injection. This theory provides a mechanistic basis for noble gas fractionation during gas migration and improves our ability to identify subsurface gas sources after post-genetic modification. Finally, we show that compositional changes due to two-phase flow can qualitatively explain the spatial compositional trends observed within the Bravo Dome natural CO2 reservoir and some regional compositional trends observed in drinking water wells overlying the Marcellus and Barnett shale regions. In both cases, only the migration of a gas with constant source composition is required, rather than multi-stage mixing and fractionation models previously proposed.

  8. Using Muons to Image the Subsurface.

    SciTech Connect

    Bonal, Nedra; Cashion, Avery Ted; Cieslewski, Grzegorz; Dorsey, Daniel J.; Foris, Adam; Miller, Timothy J.; Roberts, Barry L; Su, Jiann-Cherng; Dreesen, Wendi; Green, J. Andrew; Schwellenbach, David

    2016-11-01

    Muons are subatomic particles that can penetrate the earth 's crust several kilometers and may be useful for subsurface characterization . The absorption rate of muons depends on the density of the materials through which they pass. Muons are more sensitive to density variation than other phenomena, including gravity, making them beneficial for subsurface investigation . Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and the detector, much like a CAT scan. Currently, muon tomography can resolve features to the sub-meter scale. This work consists of three parts to address the use of muons for subsurface characterization : 1) assess the use of muon scattering for estimating density differences of common rock types, 2 ) using muon flux to detect a void in rock, 3) measure muon direction by designing a new detector. Results from this project lay the groundwork for future directions in this field. Low-density objects can be detected by muons even when enclosed in high-density material like lead, and even small changes in density (e.g. changes due to fracturing of material) can be detected. Rock density has a linear relationship with muon scattering density per rock volume when this ratio is greater than 0.10 . Limitations on using muon scattering to assess density changes among common rock types have been identified. However, other analysis methods may show improved results for these relatively low density materials. Simulations show that muons can be used to image void space (e.g. tunnels) within rock but experimental results have been ambiguous . Improvements are suggested to improve imaging voids such as tunnels through rocks. Finally, a muon detector has been designed and tested to measure muon direction, which will improve signal-to-noise ratio and help address fundamental questions about the source of upgoing muons .

  9. Tree Distributions, Subsurface Characteristics and Nitrogen Cycling

    NASA Astrophysics Data System (ADS)

    Brunner, L.; Wallace, M. C.; Brush, G.

    2014-12-01

    This study examines the connection between vegetation and geologic, soil and hydrologic subsurface characteristics of a natural deciduous forest in Oregon Ridge Park, located in the Piedmont physiographic province in Maryland, USA. A preliminary study showed the relationship between nitrogen cycling and four different species occurring on a coarse grained schist and a fine grained schist. Mineralization values for Liriodendon tulipifera were positive on the coarser grained substrate and negative on the fine grained substrate. Nitrification values were positive on both substrates. Mineralization and nitrification values were both positive for Quercus prinus on both the coarse and fine substrates. Mineralization values for Acer rubrum were negative on the coarse substrate and positive on the finer substrate, while mineralization for Quercus rubra was negative on the coarse substrate and positive on the fine schist. Nitrification was positive for Q. rubra on the coarse schist and both positive and negative on the fine schist. Resistivity analyses were performed in collaboration with the Wyoming Center for Environmental Hydrology and Geophysics (WyCEHG) along two perpendicular transects at the study site. This analysis provides indirect information on subsurface conductivity, with low resistivity being interpreted as subsurface water or clay. One transect crossed a valley with a first-order stream in the center, while the second transect was taken along the break and slope of the hillslope. All trees were identified and diameter at breast height (DBH) measured in sixty-three randomly located plots along both transects. A principle components analysis of all tree data showed four associations of species. The plots were labelled as to association. The position of the associations along the transects show a relationship between wet, dry and mesic associations with differences in transect resistivity.

  10. Surface modification by subsurface pressure induced diffusion

    SciTech Connect

    Zimmermann, Claus G.

    2012-01-23

    Polycrystalline Ag, covered with a nm thin siloxane layer, was irradiated with ultraviolet light in vacuum at 500 K. Ag particles of different aspect ratios, 50-1000 nm in size, formed on the surface, including a small fraction of nanorods. Pressurized water vapor bubbles are created in the subsurface region by hydrogen radicals photo-chemically released by the siloxane layer. They provide the driving force for a diffusive material flux along grain boundaries to the surface. This mechanism was modeled and found to agree with the experimental timescale: approximately 300 h are required for a 1000 nm particle to form.

  11. Transport of subsurface bacteria in porous media

    SciTech Connect

    Bales, R.C.; Arnold, R.G.; Gerba, C.P.

    1995-02-01

    The primary objective of this study was to develop tools with which to measure the advective transport of microorganisms through porous media. These tools were then applied to investigate the sorptive properties of representative microorganisms that were selected at random from the DOE`s deep subsurface collection of bacterial, maintained at Florida State University. The transport screening procedure that arose from this study was also used to investigate biological factors that affect the transport/sorption of biocolloids during their movement through porous media with the bulk advective flow.

  12. Airborne Electromagnetic Mapping of Subsurface Permafrost

    NASA Astrophysics Data System (ADS)

    Abraham, J. D.; Minsley, B. J.; Cannia, J. C.; Smith, B. D.; Walvoord, M. A.; Voss, C. I.; Jorgenson, T. T.; Wylie, B. K.; Anderson, L.

    2011-12-01

    Concerns over the impacts of climate change have recently energized research on the potential impacts thawing permafrost may have on groundwater flow, infrastructure, forest health, ecosystems, energy production, CO2 release, and contaminant transport. There is typically little knowledge about subsurface permafrost distributions, such as thickness and where groundwater-surface-water connections may occur through taliks. In June of 2010, the U.S. Geological Survey undertook an airborne electromagnetic (AEM) survey in the area of Fort Yukon, Alaska in order to map the 3-D distribution of permafrost and provide information for the development of groundwater models within the Yukon River Basin. Prior to the development of these models, information on areas of groundwater-surface water interaction was extremely limited. Lithology determined from a borehole drilled in Fort Yukon in 1994 agrees well with the resistivity depth sections inferred from the airborne survey. In addition to lithology, there a thermal imprint appears on the subsurface resistivity values. In the upper 20-50 m, the sections show continuous areas of high electrical resistivity, consistent with alluvial gravel deposits that are likely frozen. At depth, unfrozen gravel deposits have intermediate-to-high resistivity; frozen silts have intermediate resistivity; and unfrozen silts have low resistivity. Under the Yukon River and lakes where the subsurface is not frozen, zones of moderate resistivity intermix with areas of low resistivity. The areas of loess hills on the margins of the Yukon Flats have very-high electrical resistivity, indicating higher ice content, and are associated with the some of the greatest thickness of permafrost in the survey area. This work provides the first look into the 3-D distribution of permafrost in the areas around Fort Yukon and is a demonstration of the application of AEM to permafrost mapping. The AEM survey provides unprecedented 3-D images of subsurface electrical

  13. Detection of microbes in the subsurface

    NASA Technical Reports Server (NTRS)

    White, David C.; Tunlid, Anders

    1989-01-01

    The search for evidence of microbial life in the deep subsurface of Earth has implications for the Mars Rover Sampling Return Missions program. If suitably protected environments can be found on Mars then the instrumentation to detect biomarkers could be used to examine the molecular details. Finding a lipid in Martian soil would represent possibly the simplest test for extant or extinct life. A device that could do a rapid extraction possibly using the supercritical fluid technology under development now with a detection of the carbon content would clearly indicate a sample to be returned.

  14. Instrumented Moles for Planetary Subsurface Regolith Studies

    NASA Astrophysics Data System (ADS)

    Richter, L. O.; Coste, P. A.; Grzesik, A.; Knollenberg, J.; Magnani, P.; Nadalini, R.; Re, E.; Romstedt, J.; Sohl, F.; Spohn, T.

    2006-12-01

    Soil-like materials, or regolith, on solar system objects provide a record of physical and/or chemical weathering processes on the object in question and as such possess significant scientific relevance for study by landed planetary missions. In the case of Mars, a complex interplay has been at work between impact gardening, aeolian as well as possibly fluvial processes. This resulted in regolith that is texturally as well as compositionally layered as hinted at by results from the Mars Exploration Rover (MER) missions which are capable of accessing shallow subsurface soils by wheel trenching. Significant subsurface soil access on Mars, i.e. to depths of a meter or more, remains to be accomplished on future missions. This has been one of the objectives of the unsuccessful Beagle 2 landed element of the ESA Mars Express mission having been equipped with the Planetary Underground Tool (PLUTO) subsurface soil sampling Mole system capable of self-penetration into regolith due to an internal electro-mechanical hammering mechanism. This lightweight device of less than 900 g mass was designed to repeatedly obtain and deliver to the lander regolith samples from depths down to 2 m which would have been analysed for organic matter and, specifically, organic carbon from potential extinct microbial activity. With funding from the ESA technology programme, an evolved Mole system - the Instrumented Mole System (IMS) - has now been developed to a readiness level of TRL 6. The IMS is to serve as a carrier for in situ instruments for measurements in planetary subsurface soils. This could complement or even eliminate the need to recover samples to the surface. The Engineering Model hardware having been developed within this effort is designed for accommodating a geophysical instrument package (Heat Flow and Physical Properties Package, HP3) that would be capable of measuring regolith physical properties and planetary heat flow. The chosen design encompasses a two-body Mole

  15. Physiologically anaerobic microorganisms of the deep subsurface

    SciTech Connect

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  16. Surface modification by subsurface pressure induced diffusion

    NASA Astrophysics Data System (ADS)

    Zimmermann, Claus G.

    2012-01-01

    Polycrystalline Ag, covered with a nm thin siloxane layer, was irradiated with ultraviolet light in vacuum at 500 K. Ag particles of different aspect ratios, 50-1000 nm in size, formed on the surface, including a small fraction of nanorods. Pressurized water vapor bubbles are created in the subsurface region by hydrogen radicals photo-chemically released by the siloxane layer. They provide the driving force for a diffusive material flux along grain boundaries to the surface. This mechanism was modeled and found to agree with the experimental timescale: approximately 300 h are required for a 1000 nm particle to form.

  17. Low temperature monitoring system for subsurface barriers

    DOEpatents

    Vinegar, Harold J.; McKinzie, II. Billy John

    2009-08-18

    A system for monitoring temperature of a subsurface low temperature zone is described. The system includes a plurality of freeze wells configured to form the low temperature zone, one or more lasers, and a fiber optic cable coupled to at least one laser. A portion of the fiber optic cable is positioned in at least one freeze well. At least one laser is configured to transmit light pulses into a first end of the fiber optic cable. An analyzer is coupled to the fiber optic cable. The analyzer is configured to receive return signals from the light pulses.

  18. ESP's placed in horizontal lateral increase production

    SciTech Connect

    Gallup, A.; Wilson, B.L. ); Marshall, R. )

    1990-06-18

    By design, the electric submersible pump (ESP) is an effective method of lifting fluids from horizontal wells. But this ESP application does have unique installation and operating parameters that need to be considered. ESP's have been used for many years in directional wells. This application provides an experience base for understanding deflection limits on the unit. To avoid damaging the ESP, special equipment may be required in some horizontal installations. This paper discusses how several ESP's have been designed specifically for medium-radius wells. In these applications, the deeper pump setting provides for a significant increase in production rate. In general, to realize the full benefit of a horizontal installation, the ESP should be considered when planning, drilling, and completing the well.

  19. The horizontal computerized rotational impulse test.

    PubMed

    Furman, Joseph M; Shirey, Ian; Roxberg, Jillyn; Kiderman, Alexander

    2016-01-01

    Whole-body impulsive rotations were used to overcome several limitations associated with manual head impulse testing. A computer-controlled rotational chair delivered brief, whole-body, earth-vertical axis yaw impulsive rotations while eye movements were measured using video-oculography. Results from an unselected group of 20 patients with dizziness and a group of 22 control subjects indicated that the horizontal computerized rotational head impulse test (crHIT) is well-tolerated and provides an estimate of unidirectional vestibulo-ocular reflex gain comparable to results from caloric testing. This study demonstrates that the horizontal crHIT is a new assessment tool that overcomes many of the limitations of manual head impulse testing and provides a reliable laboratory-based measure of unilateral horizontal semicircular canal function.

  20. Can Venice be raised by pumping water underground? A pilot project to help decide

    NASA Astrophysics Data System (ADS)

    Castelletto, N.; Ferronato, M.; Gambolati, G.; Putti, M.; Teatini, P.

    2008-01-01

    Recent field evidence suggests that injecting fluids below the ground surface can induce an anthropogenic land uplift of a few tens of centimeters over a time interval that may range from a few months to a few years. At the same time, new modeling studies using a lot of realistic hydrogeological and geomechanical information from the northern Adriatic basin indicate that pumping seawater into a 600-800 m deep brackish aquifer below the Venice Lagoon might help raise the city uniformly by 25-30 cm over 10 years (a). This could provide Venice with an important innovative defence from and a substantial mitigation to the so-called "acqua alta," i.e., the increasingly frequent floods that plague the city. To test the feasibility of an actual program of anthropogenic Venice uplift, a pilot project is designed with the aim of investigating the occurrence over a limited area selected on purpose within or in the margin of the lagoon where three boreholes down to 800 m are drilled and seawater properly treated for geochemical compatibility is pumped into the selected aquifer during 3 a. Using an improved reconstruction of the geology and lithostratigraphy from a new seismic survey to be carried out in the lagoon subsurface, the pilot project plans the instrumentation of the injection wells and other boreholes for the continuous monitoring and accurate measurement of (1) pore water overpressure; (2) expansion of the injected unit by the radioactive marker technique; (3) compaction, if any, of the upper fresh water aquifer system with the aid of an extensometer; and (4) vertical and horizontal motions of land surface via spirit leveling, GPS and interferometric synthetic aperture radar. Preliminary numerical simulations show that a constant saltwater injection rate of 12 × 103 m3 s-1 from each well might provide a maximum 7 cm uplift at the center of the selected site over a 3-a time, namely, a limited amount that is nevertheless accurately measurable and should not raise

  1. Crystal structure of laser-induced subsurface modifications in Si

    DOE PAGES

    Verburg, P. C.; Smillie, L. A.; Römer, G. R. B. E.; ...

    2015-06-04

    Laser-induced subsurface modification of dielectric materials is a well-known technology. Applications include the production of optical components and selective etching. In addition to dielectric materials, the subsurface modification technology can be applied to silicon, by employing near to mid-infrared radiation. An application of subsurface modifications in silicon is laser-induced subsurface separation, which is a method to separate wafers into individual dies. Other applications for which proofs of concept exist are the formation of waveguides and resistivity tuning. However, limited knowledge is available about the crystal structure of subsurface modifications in silicon. In this paper, we investigate the geometry and crystalmore » structure of laser-induced subsurface modifications in monocrystalline silicon wafers. Finally, in addition to the generation of lattice defects, we found that transformations to amorphous silicon and Si-iii/Si-xii occur as a result of the laser irradiation.« less

  2. Crystal structure of laser-induced subsurface modifications in Si

    SciTech Connect

    Verburg, P. C.; Smillie, L. A.; Römer, G. R. B. E.; Haberl, B.; Bradby, J. E.; Williams, J. S.; Huis in ’t Veld, A. J.

    2015-06-04

    Laser-induced subsurface modification of dielectric materials is a well-known technology. Applications include the production of optical components and selective etching. In addition to dielectric materials, the subsurface modification technology can be applied to silicon, by employing near to mid-infrared radiation. An application of subsurface modifications in silicon is laser-induced subsurface separation, which is a method to separate wafers into individual dies. Other applications for which proofs of concept exist are the formation of waveguides and resistivity tuning. However, limited knowledge is available about the crystal structure of subsurface modifications in silicon. In this paper, we investigate the geometry and crystal structure of laser-induced subsurface modifications in monocrystalline silicon wafers. Finally, in addition to the generation of lattice defects, we found that transformations to amorphous silicon and Si-iii/Si-xii occur as a result of the laser irradiation.

  3. The subsurface origin of microbial life on the Earth.

    PubMed

    Trevors, J T

    2002-10-01

    Life on Earth can be divided into life on the surface made possible by photosynthesis and subsurface life with chemical energy as the driving force. An understanding of both environments is central to our understanding of the origin of life, the search for novel microbial species in the subsurface and for extraterrestrial life or life signatures. In this manuscript, the surface and subsurface worlds are examined with a focus on the origin or assembly of bacterial life.

  4. Evaluation of Subsurface Engineered Barriers at Waste Sites

    DTIC Science & Technology

    1998-08-01

    Evaluation of Subsurface Engineered Barriers at Waste Sites United States Environmental Protection Agency Office of Solid Waste and Emergency...of Subsurface Engineered Barriers at Waste Sites 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...1998 www.epa.gov clu-in.com EVALUATION OF SUBSURFACE ENGINEERED BARRIERS AT WASTE SITES i NOTICE This document was prepared for the U.S. Environmental

  5. Atmospheric energy for subsurface life on Mars?

    PubMed Central

    Weiss, Benjamin P.; Yung, Yuk L.; Nealson, Kenneth H.

    2000-01-01

    The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H2 and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H2 and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H2O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life. PMID:10660689

  6. The subsurface of Pluto from submillimetre observations

    NASA Astrophysics Data System (ADS)

    Greaves, J. S.; Whitelaw, A. C. M.; Bendo, G. J.

    2015-04-01

    Surface areas on Pluto change in brightness and colour, at optical to infrared wavelengths, over time-scales as short as years. The subsurface contains a reservoir of frozen volatiles, but little is known about it because Pluto is out of reach for cm-radar. Here we present a 0.85 mm wavelength light curve of the Pluto system, from archival data taken in 1997 August with the SCUBA (Submillimetre Common-User Bolometer Array) camera on the James Clerk Maxwell Telescope (JCMT). This wavelength probes for the first time to just below the skin depth of thermal changes over Pluto's day. The light curve differs significantly from counterparts in the mid- to far-infrared, in a longitude range that is optically dark on Pluto's surface. An estimate from Herschel of the 0.5 mm flux in 2012 is comparable to the mean 0.45 mm flux from SCUBA in 1997, suggesting that layers centimetres below the surface have not undergone any gross temperature change. The longitudes that are relatively submillimetre-faint could have a different emissivity, perhaps with a subsurface layer richer in nitrogen or methane ices than at the surface. The Radio Science Experiment (REX) instrument on New Horizons may be able to constrain physical properties deeper down, as it looks back on Pluto's nightside after the 2015 July flyby.

  7. Phylogenetic relationships among subsurface microorganisms. Progress report

    SciTech Connect

    Nierzwicki-Bauer, S.A.

    1991-12-31

    This project involves the development of group specific 16S ribosomal RNA-targeted oligonucleotide hybridization probes for the rapid detection of specific types of subsurface organisms (e.g., groups of microbes that share certain physiological traits). Major accomplishments for the period of 6/91 to 12/1/91 are described. Nine new probes have been synthesized on the basis of published 16S rRNA sequence data from the Ribosomal Database Project. We have initiated rapid screening of many of the subsurface microbial isolates obtained from the P24 borehole at the Savannah River Site. To date, we have screened approximately 50% of the isolates from P24. We have optimized our {und in situ} hybridization technique, and have developed a cell blot hybridization technique to screen 96 samples on a single blot. This is much faster than reading 96 individual slides. Preliminary experiments have been carried out which indicate specific nutrients can be used to amplify rRNA only in those organisms capable of metabolizing those nutrients. 1 tab., 2 figs.

  8. Human utilization of subsurface extraterrestrial environments.

    PubMed

    Boston, P J; Frederick, R D; Welch, S M; Werker, J; Meyer, T R; Sprungman, B; Hildreth-Werker, V; Thompson, S L; Murphy, D L

    2003-06-01

    Caves have been used in the ancient past as shelter or habitat by many organisms (including humans). Since antiquity, humans have explored caves for the minerals they contain and sometimes for ceremonial purposes. Over the past century, caves have become the target of increasing exploration, scientific research, and recreation. The use of caves on extraterrestrial bodies for human habitation has been suggested by several investigators. Lunar lava tube bases received early attention because lava tubes were clearly visible in lunar images from the Apollo Era. More recently, Mars Observer Camera data has shown us clear evidence of large tubes visible in a number of volcanic regions on Mars. The budding field of cave geomicrobiology has direct application to questions about subsurface life on other planets. Caves contain many unusual organisms making their living from unlikely materials like manganese, iron, and sulfur. This makes caves and other subsurface habitats prime targets for astrobiological missions to Mars and possibly other bodies. We present the results of a completed Phase I and on-going Phase II NASA Institute for Advanced Concepts (NIAC) study that intensively examines the possibilities of using extraterrestrial caves as both a resource for human explorers and as a highly promising scientific target for both robotic and future human missions to Mars and beyond.

  9. Atmospheric energy for subsurface life on Mars?

    NASA Technical Reports Server (NTRS)

    Weiss, B. P.; Yung, Y. L.; Nealson, K. H.

    2000-01-01

    The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H(2) and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H(2) and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H(2)O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.

  10. Atmospheric energy for subsurface life on Mars?

    PubMed

    Weiss, B P; Yung, Y L; Nealson, K H

    2000-02-15

    The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H(2) and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H(2) and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H(2)O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.

  11. Method and apparatus for subsurface exploration

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2002-01-01

    A subsurface explorer (SSX) for exploring beneath the terrestrial surface of planetary bodies such as the Earth, Mars, or comets. This exploration activity utilizes appropriate sensors and instrument to evaluate the composition, structure, mineralogy and possibly biology of the subsurface medium, as well as perhaps the ability to return samples of that medium back to the surface. The vehicle comprises an elongated skin or body having a front end and a rear end, with a nose piece at the front end for imparting force to composition material of the planetary body. Force is provided by a hammer mechanism to the back side of a nose piece from within the body of the vehicle. In the preferred embodiment, a motor spins an intermediate shaft having two non-uniform threads along with a hammer which engages these threads with two conical rollers. A brake assembly halts the rotation of the intermediate shaft, causing the conical roller to spin down the non-uniform thread to rapidly and efficiently convert the rotational kinetic energy of the hammer into translational energy.

  12. Improving subsurface hydrology in Earth System Models

    NASA Astrophysics Data System (ADS)

    Volk, J. M.; Clark, M. P.; Swenson, S. C.; Lawrence, D. M.; Tyler, S. W.

    2015-12-01

    Hydrologic processes that govern storage and transport of soil water and groundwater can have strong dynamic relationships with biogeochemical and atmospheric processes. This understanding has lead to a push to improve subsurface hydrologic parametrization in Earth System Models. Here we present results related to improving the implementation of soil moisture distribution, groundwater recharge/discharge, and subsurface drainage in the Community Land Model (CLM) which is the land surface model in the Community Earth System Model. First we identified geo-climatically different locations around the world to develop test cases. For each case we compare the vertical soil moisture distribution from the different implementations of 1D Richards equation, considering the boundary conditions, the treatment of the groundwater sink term, the vertical discretization, and the time stepping schemes. Generally, large errors in the hydrologic mass balance within the soil column occur when there is a large vertical gradient in soil moisture or when there is a shallow water table within a soil column. We then test the sensitivity of the algorithmic parameters that control temporal discretization and error tolerance of the adaptive time-stepping scheme to help optimize its computational efficiency. In addition, we vary the spatial discretization of soil layers (i.e. quantity of layers and their thicknesses) to better understand the sensitivity of vertical discretization of soil columns on soil moisture variability in ESMs. We present multivariate and multi-scale evaluation for the different model options and suggest ways to move forward with future model improvements.

  13. Highly parameterized inversion using hydraulic tomography and pilot points

    NASA Astrophysics Data System (ADS)

    Jimenez, Santos; Brauchler, Ralf; Bayer, Peter

    2013-04-01

    This work presents a new methodology to characterize subsurface hydraulic parameter distribution using the information provided by hydraulic tomography (HT) as prior information, in combination with pilot point based inversion. HT is a methodology that facilitates characterizing the spatial variation of hydraulic conductivity and storage at a higher level of detail than traditional field methods. It utilizes sequential pumping or injection at a well, which is divided in different vertical sections by, for instance, a packer. During the perturbation of the hydraulic regime from each section, the response of the aquifer is monitored at depth-dependent observation points in surrounding wells, obtaining the pressure response. This data set is treated with an eikonal solver, which yields a fast reconstruction of the heterogeneity present in the aquifer. However, by this, only the possible spatial variability of diffusivity is interpreted, and the heterogeneity of the components storage and hydraulic conductivity are not derived. We suggest exploiting the diffusivity tomograms in a pilot points framework. Additionally, spatial reliability of the tomograms is determined using singular value decomposition. This information and clustering allows for determining an initial guess of the hydraulic facies distribution by HT, which is the basis for assigning and positioning pilot points in a numerical flow model. In order to inform the inverse problem about the hydrofacies distribution, the relationships between pilot points are modelled by a graph and by implementing the adjacency matrix using Tikhonov regularization. This methodology was successfully tested at the highly heterogeneous aquifer Herten analog.

  14. Subsurface Defect Detection in FRP Composites Using Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Halabe, U. B.; Vasudevan, A.; GangaRao, H. V. S.; Klinkhachorn, P.; Lonkar, G.

    2005-04-01

    This paper demonstrates the use of digital infrared thermography to detect subsurface defects such as debonds and delaminations in Fiber Reinforced Polymer (FRP) bridge decks. Simulated sub-surface debonds and delaminations were inserted between the wearing surface and the underlying FRP deck specimens. The infrared thermography technique was used to detect these embedded subsurface defects. The use of various cooling and heating methods, including solar radiation, was explored. Surface temperature-time curves were established for different types and sizes of subsurface defects.

  15. Modeling subsurface stormflow initiation in low-relief landscapes

    NASA Astrophysics Data System (ADS)

    Hopp, Luisa; Vaché, Kellie B.; Rhett Jackson, C.; McDonnell, Jeffrey J.

    2015-04-01

    Shallow lateral subsurface flow as a runoff generating mechanism at the hillslope scale has mostly been studied in steeper terrain with typical hillside angles of 10 - 45 degrees. These studies have shown that subsurface stormflow is often initiated at the interface between a permeable upper soil layer and a lower conductivity impeding layer, e.g. a B horizon or bedrock. Many studies have identified thresholds of event size and soil moisture states that need to be exceeded before subsurface stormflow is initiated. However, subsurface stormflow generation on low-relief hillslopes has been much less studied. Here we present a modeling study that investigates the initiation of subsurface stormflow on low-relief hillslopes in the Upper Coastal Plain of South Carolina, USA. Hillslopes in this region typically have slope angles of 2-5 degrees. Topsoils are sandy, underlain by a low-conductivity sandy clay loam Bt horizon. Subsurface stormflow has only been intercepted occasionally in a 120 m long trench, and often subsurface flow was not well correlated with stream signals, suggesting a disconnect between subsurface flow on the hillslopes and stream flow. We therefore used a hydrologic model to better understand which conditions promote the initiation of subsurface flow in this landscape, addressing following questions: Is there a threshold event size and soil moisture state for producing lateral subsurface flow? What role does the spatial pattern of depth to the impeding clay layer play for subsurface stormflow dynamics? We reproduced a section of a hillslope, for which high-resolution topographic data and depth to clay measurements were available, in the hydrologic model HYDRUS-3D. Soil hydraulic parameters were based on experimentally-derived data. The threshold analysis was first performed using hourly climate data records for 2009-2010 from the study site to drive the simulation. For this period also trench measurements of subsurface flow were available. In addition

  16. Pilot-optimal augmentation synthesis

    NASA Technical Reports Server (NTRS)

    Schmidt, D. K.

    1978-01-01

    An augmentation synthesis method usable in the absence of quantitative handling qualities specifications, and yet explicitly including design objectives based on pilot-rating concepts, is presented. The algorithm involves the unique approach of simultaneously solving for the stability augmentation system (SAS) gains, pilot equalization and pilot rating prediction via optimal control techniques. Simultaneous solution is required in this case since the pilot model (gains, etc.) depends upon the augmented plant dynamics, and the augmentation is obviously not a priori known. Another special feature is the use of the pilot's objective function (from which the pilot model evolves) to design the SAS.

  17. An Estimation Of The Geoelectric Features Of Planetary Shallow Subsurfaces With TAPIR Antennae

    NASA Astrophysics Data System (ADS)

    Le Gall, A.; Reineix, A.; Ciarletti, V.; Jean-Jacques, B.; Ney, R.; Dolon, F.; Corbel, C.

    2005-12-01

    Exploring the interior of Mars and searching for water reservoirs, either in the form of ice or of liquid water, was one of the main scientific objectives of the NETLANDER project. In that frame, the CETP (Centre d'Etude des Environnements Terrestre et Planetaires) has developed an imaging ground penetrating radar (GPR), called TAPIR (Terrestrial And Planetary Investigation by Radar). Operating from a fixed position and at low frequencies (from 2 to 4MHz), this instrument allows to retrieve not only the distance but also the inclination of deep subsurface reflectors by measuring the two horizontal electrical components and the three magnetic components of the reflected waves. In 2004, ground tests have been successfully carried out on the Antarctic Continent; the bedrock, lying under a thick layer of ice (until 1200m), was detected and part of its relief was revealed. Yet, knowing the electric parameters of the close subsurface is required to correctly process the measured electric and magnetic components of the echoes and deduce their propagation vector. In addition, these electric parameters can bring a very interesting piece of information on the nature of the material in the shallow underground. We have therefore looked for a possible method (appropriate for a planetary mission) to evaluate them using a special mode of operation of the radar. This method relies on the fact that the electrical characteristics of the transmitting electric antennas (current along the antenna, driving-point impedance.) depend on the nature of the ground on which the radar is lying. If this dependency is significant enough, geological parameters of the subsurface can be deduced from the analysis of specific measurements. We have thus performed a detailed experimental and theoretical study of the TAPIR resistively loaded electrical dipoles to get a precise understanding of the radar transmission and assess the role of the electric parameters of the underground. In this poster, we

  18. Treatment of laboratory wastewater in a tropical constructed wetland comparing surface and subsurface flow.

    PubMed

    Meutia, A A

    2001-01-01

    Wastewater treatment by constructed wetland is an appropriate technology for tropical developing countries like Indonesia because it is inexpensive, easily maintained, and has environmentally friendly and sustainable characteristics. The aim of the research is to examine the capability of constructed wetlands for treating laboratory wastewater at our Center, to investigate the suitable flow for treatment, namely vertical subsurface or horizontal surface flow, and to study the effect of the seasons. The constructed wetland is composed of three chambered unplanted sedimentation tanks followed by the first and second beds, containing gravel and sand, planted with Typha sp.; the third bed planted with floating plant Lemna sp.; and a clarifier with two chambers. The results showed that the subsurface flow in the dry season removed 95% organic carbon (COD) and total phosphorus (T-P) respectively, and 82% total nitrogen (T-N). In the transition period from the dry season to the rainy season, COD removal efficiency decreased to 73%, T-N increased to 89%, and T-P was almost the same as that in the dry season. In the rainy season COD and T-N removal efficiencies increased again to 95% respectively, while T-P remained unchanged. In the dry season, COD and T-P concentrations in the surface flow showed that the removal efficiencies were a bit lower than those in the subsurface flow. Moreover, T-N removal efficiency was only half as much as that in the subsurface flow. However, in the transition period, COD removal efficiency decreased to 29%, while T-N increased to 74% and T-P was still constant, around 93%. In the rainy season, COD and T-N removal efficiencies increased again to almost 95%. On the other hand, T-P decreased to 76%. The results show that the constructed wetland is capable of treating the laboratory wastewater. The subsurface flow is more suitable for treatment than the surface flow, and the seasonal changes have effects on the removal efficiency.

  19. Microbial communities in the deep subsurface

    NASA Astrophysics Data System (ADS)

    Krumholz, Lee R.

    The diversity of microbial populations and microbial communities within the earth's subsurface is summarized in this review. Scientists are currently exploring the subsurface and addressing questions of microbial diversity, the interactions among microorganisms, and mechanisms for maintenance of subsurface microbial communities. Heterotrophic anaerobic microbial communities exist in relatively permeable sandstone or sandy sediments, located adjacent to organic-rich deposits. These microorganisms appear to be maintained by the consumption of organic compounds derived from adjacent deposits. Sources of organic material serving as electron donors include lignite-rich Eocene sediments beneath the Texas coastal plain, organic-rich Cretaceous shales from the southwestern US, as well as Cretaceous clays containing organic materials and fermentative bacteria from the Atlantic Coastal Plain. Additionally, highly diverse microbial communities occur in regions where a source of organic matter is not apparent but where igneous rock is present. Examples include the basalt-rich subsurface of the Columbia River valley and the granitic subsurface regions of Sweden and Canada. These subsurface microbial communities appear to be maintained by the action of lithotrophic bacteria growing on H2 that is chemically generated within the subsurface. Other deep-dwelling microbial communities exist within the deep sediments of oceans. These systems often rely on anaerobic metabolism and sulfate reduction. Microbial colonization extends to the depths below which high temperatures limit the ability of microbes to survive. Energy sources for the organisms living in the oceanic subsurface may originate as oceanic sedimentary deposits. In this review, each of these microbial communities is discussed in detail with specific reference to their energy sources, their observed growth patterns, and their diverse composition. This information is critical to develop further understanding of subsurface

  20. Horizontal Axis Levitron--A Physics Demonstration

    ERIC Educational Resources Information Center

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the "spignet". Precession is fundamental to nuclear magnetic…

  1. Teaching Activities on Horizontal Nuclear Proliferation.

    ERIC Educational Resources Information Center

    Zola, John

    1990-01-01

    Provides learning activities concerning the horizontal proliferation of nuclear weapons. Includes step-by-step directions for four activities: (1) the life cycle of nuclear weapons; (2) nuclear nonproliferation: pros and cons; (3) the nuclear power/nuclear weapons connection; and (4) managing nuclear proliferation. (NL)

  2. Horizontally separated 1-in-1 crossing insertions

    SciTech Connect

    Syphers, M.J.

    1985-10-01

    Previous to this workshop, realistic lattices have been developed for vertically separated l-in-l (e.g., D.E. Johnson, A.A. Garren) and 2-in-1 (e.g., S. Heifets) magnets as well as for horizontally separated 2-in-l magnets (e.g., SSC RDS). Bringing together the widely separated ({approximately}60-70 cm) beams in a reasonable length of tunnel and keeping the dispersion zero at the interaction point has been difficult in the vertical l-in-l case. Most designs have required spacial 2-in-1 quadrupoles near the interaction point where the beams are separated by 15 cm or less. It is not clear that such magnets, as dictated by some of these lattice designs, can easily be built. The purpose of this exercise is to provide a crossing insertion for a realistic lattice which involves horizontally separated l-in-l magnets. The following horizontal crossing insertions, which incorporate the dispersion suppressors and phase trombones into the major arcs, need no special 2-in-1 magnets near the interaction point. The dispersion at the IP created by the horizontal crossing can be cancelled by the dispersion suppressor and one set of triplets.

  3. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors. (a)(1... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside the prescribed sectors. (2) For sternlights and masthead lights and at 22.5 degrees abaft the beam for...

  4. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors. (a)(1... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside the prescribed sectors. (2) For sternlights and masthead lights and at 22.5 degrees abaft the beam for...

  5. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors. (a)(1... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside the prescribed sectors. (2) For sternlights and masthead lights and at 22.5 degrees abaft the beam for...

  6. Cutting Down the Tall Poppies: Horizontal Violence.

    ERIC Educational Resources Information Center

    Funk, Carole

    Many women in educational leadership positions experience negative treatment from female teachers and female superintendents. This phenomenon is known as horizontal violence, "the curious behavior of members of oppressed groups who often lash out at their peers in response to oppression instead of attacking their oppressors." This paper explores…

  7. Detecting Highways of Horizontal Gene Transfer

    NASA Astrophysics Data System (ADS)

    Bansal, Mukul S.; Gogarten, J. Peter; Shamir, Ron

    In a horizontal gene transfer (HGT) event a gene is transferred between two species that do not share an ancestor-descendant relationship. Typically, no more than a few genes are horizontally transferred between any two species. However, several studies identified pairs of species between which many different genes were horizontally transferred. Such a pair is said to be linked by a highway of gene sharing. We present a method for inferring such highways. Our method is based on the fact that the evolutionary histories of horizontally transferred genes disagree with the corresponding species phylogeny. Specifically, given a set of gene trees and a trusted rooted species tree, each gene tree is first decomposed into its constituent quartet trees and the quartets that are inconsistent with the species tree are identified. Our method finds a pair of species such that a highway between them explains the largest (normalized) fraction of inconsistent quartets. For a problem on n species, our method requires O(n 4) time, which is optimal with respect to the quartets input size. An application of our method to a dataset of 1128 genes from 11 cyanobacterial species, as well as to simulated datasets, illustrates the efficacy of our method.

  8. Detecting highways of horizontal gene transfer.

    PubMed

    Bansal, Mukul S; Banay, Guy; Gogarten, J Peter; Shamir, Ron

    2011-09-01

    In a horizontal gene transfer (HGT) event, a gene is transferred between two species that do not have an ancestor-descendant relationship. Typically, no more than a few genes are horizontally transferred between any two species. However, several studies identified pairs of species between which many different genes were horizontally transferred. Such a pair is said to be linked by a highway of gene sharing. We present a method for inferring such highways. Our method is based on the fact that the evolutionary histories of horizontally transferred genes disagree with the corresponding species phylogeny. Specifically, given a set of gene trees and a trusted rooted species tree, each gene tree is first decomposed into its constituent quartet trees and the quartets that are inconsistent with the species tree are identified. Our method finds a pair of species such that a highway between them explains the largest (normalized) fraction of inconsistent quartets. For a problem on n species and m input quartet trees, we give an efficient O(m + n(2))-time algorithm for detecting highways, which is optimal with respect to the quartets input size. An application of our method to a dataset of 1128 genes from 11 cyanobacterial species, as well as to simulated datasets, illustrates the efficacy of our method.

  9. Uniform head in horizontal and vertical wells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The steady-state head within a fully penetrating well may be estimated by evaluating the Thiem equation at the radius of the well. A method is presented here to extend results from the Thiem equation to horizontal wells and to partially penetrating wells. The particular model used in this investigat...

  10. Orthodontic extrusion of horizontally impacted mandibular molars

    PubMed Central

    Ma, Zhigui; Yang, Chi; Zhang, Shanyong; Xie, Qianyang; Shen, Yuqing; Shen, Pei

    2014-01-01

    Objective: To introduce and evaluate a novel approach in treating horizontally impacted mandibular second and third molars. Materials and methods: An orthodontic technique was applied for treatment of horizontally impacted mandibular second and third molars, which included a push-type spring for rotation first, and then a cantilever for extrusion. There were 8 mandibular third molars (M3s) and 2 second molars (M2s) in this study. Tooth mobility, extraction time, the inclination and parallelism of the impacted tooth, alveolar bone height of the adjacent tooth, and the relationship of impacted M3 and the inferior alveolar nerve (IAN) were evaluated. Results: Two horizontally impacted M2s could be upright in the arch and good occlusal relationships were obtained after treatment. All impacted M3s were successfully separated from the IAN, without any neurologic consequences. The average extraction time was 5 minutes. There was a significant change in the inclination and parallelism of the impacted tooth after treatment. A new bone apposition with the average height of 3.2 mm was noted distal to the adjacent tooth. Conclusions: This two-step orthodontic technique as presented here may be a safe and feasible alternative in management of severely horizontally impacted mandibular molars, which achieves a successful separation of M3s from the IAN and an excellent position for M2s. PMID:25419364

  11. Electroluminescence from completely horizontally oriented dye molecules

    NASA Astrophysics Data System (ADS)

    Komino, Takeshi; Sagara, Yuta; Tanaka, Hiroyuki; Oki, Yuji; Nakamura, Nozomi; Fujimoto, Hiroshi; Adachi, Chihaya

    2016-06-01

    A complete horizontal molecular orientation of a linear-shaped thermally activated delayed fluorescent guest emitter 2,6-bis(4-(10Hphenoxazin-10-yl)phenyl)benzo[1,2-d:5,4-d'] bis(oxazole) (cis-BOX2) was obtained in a glassy host matrix by vapor deposition. The orientational order of cis-BOX2 depended on the combination of deposition temperature and the type of host matrix. Complete horizontal orientation was obtained when a thin film with cis-BOX2 doped in a 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) host matrix was fabricated at 200 K. The ultimate orientation of guest molecules originates from not only the kinetic relaxation but also the kinetic stability of the deposited guest molecules on the film surface during film growth. Utilizing the ultimate orientation, a highly efficient organic light-emitting diode with the external quantum efficiency of 33.4 ± 2.0% was realized. The thermal stability of the horizontal orientation of cis-BOX2 was governed by the glass transition temperature (Tg) of the CBP host matrix; the horizontal orientation was stable unless the film was annealed above Tg.

  12. Stereoscopic watermarking by horizontal noise mean shifting

    NASA Astrophysics Data System (ADS)

    Lee, Ji-Won; Kim, Hee-Dong; Choi, Hak-Yeol; Choi, Sung-Hee; Lee, Heung-Kyu

    2012-03-01

    Depth-image-based rendering (DIBR) is a method to represent a stereoscopic content. The DIBR consists of a monoscopic center view and an associated per-pixel depth map. Using these two components and given depth condition from a user, the DIBR renders left and right views. The advantages of DIBR are numerous. The user can choose not only the monoscopic or stereoscopic view selectively, but also the depth condition what he prefers when he watches a stereoscopic content. However, in the view of copyright protection, since not only the center view but also each left or right view can be used as a monoscopic content when they are illegally distributed, the watermark signal which is embedded in the center view must have an ability to protect the respective three views. In this study, we solve this problem by exploiting the horizontal noise mean shifting (HNMS) technique. We exploit the fact that the objects in the view are shifted only to horizontal way when the center view renders to the left and right views. Using this fact, the proposed stereoscopic watermarking scheme moves the mean of horizontal noise histogram which is invariant to horizontal shifting, and we achieve good performance as shown in the experimental results.

  13. Shallow Horizontal GCHP Effectiveness in Arid Climate Soils

    NASA Astrophysics Data System (ADS)

    North, Timothy James

    Ground coupled heat pumps (GCHPs) have been used successfully in many environments to improve the heating and cooling efficiency of both small and large scale buildings. In arid climate regions, such as the Phoenix, Arizona metropolitan area, where the air condi-tioning load is dominated by cooling in the summer, GCHPs are difficult to install and operate. This is because the nature of soils in arid climate regions, in that they are both dry and hot, renders them particularly ineffective at dissipating heat. The first part of this thesis addresses applying the SVHeat finite element modeling soft-ware to create a model of a GCHP system. Using real-world data from a prototype solar-water heating system coupled with a ground-source heat exchanger installed in Menlo Park, California, a relatively accurate model was created to represent a novel GCHP panel system installed in a shallow vertical trench. A sensitivity analysis was performed to evaluate the accuracy of the calibrated model. The second part of the thesis involved adapting the calibrated model to represent an ap-proximation of soil conditions in arid climate regions, using a range of thermal properties for dry soils. The effectiveness of the GCHP in the arid climate region model was then evaluated by comparing the thermal flux from the panel into the subsurface profile to that of the prototype GCHP. It was shown that soils in arid climate regions are particularly inefficient at heat dissipation, but that it is highly dependent on the thermal conductivity inputted into the model. This demonstrates the importance of proper site characterization in arid climate regions. Finally, several soil improvement methods were researched to evaluate their potential for use in improving the effectiveness of shallow horizontal GCHP systems in arid climate regions.

  14. Deformation of the subsurface silurian and devonian rocks of the southern tier of New York State

    NASA Astrophysics Data System (ADS)

    Beinkafner, K. J.

    Seismic, lithofacies, and structural interpretations are integrated into a tectonic model. For the Middle Ordovician to Middle Devonian interval, subsurface lithofacies are mapped from well sample logs. The elusive decollement of the Allegheny Plateau is identified and mapped from repeat sections on gamma ray logs. In the eastern counties, Unit F (salt) sections of the Syracuse Formation are vertically repeated two and three times along splays originating at decollement. The dome shape of the top of the Syracuse Formation and a planar base suggest a thin-skinned tectonic origin. In Steuben and Allegheny Counties, Unit E sections are overthickened and the detachment surface is near the base of Unit E. In Chautauqua County decollement terminates in a structure with northeast strike. At the northwest edge of the underlying salt beds, horizontal decollement bends upward forming structural petroleum traps. A decollement tectonic model for the southern tier is proposed in which individual buried fault blocks display differential movement above detachment zones.

  15. CWM1: a general model to describe biokinetic processes in subsurface flow constructed wetlands.

    PubMed

    Langergraber, Guenter; Rousseau, Diederik P L; García, Joan; Mena, Javier

    2009-01-01

    This paper presents the Constructed Wetland Model No1 (CWM1), a general model to describe biochemical transformation and degradation processes for organic matter, nitrogen and sulphur in subsurface flow constructed wetlands. The main objective of CWM1 is to predict effluent concentrations from constructed wetlands without predicting gaseous emissions. CWM1 describes aerobic, anoxic and anaerobic processes and is therefore applicable to both horizontal and vertical flow systems. 17 processes and 16 components (8 soluble and 8 particulate) are considered. CWM1 is based on the mathematical formulation as introduced by the IWA Activated Sludge Models (ASMs). It is important to note that besides the biokinetic model a number of other processes including porous media hydrodynamics, the influence of plants, the transport of particles/suspended matter to describe clogging processes, adsorption and desorption processes and physical re-aeration must be considered for the formulation of a full model for constructed wetlands.

  16. NSTAR Smart Grid Pilot

    SciTech Connect

    Rabari, Anil; Fadipe, Oloruntomi

    2014-03-31

    NSTAR Electric & Gas Corporation (“the Company”, or “NSTAR”) developed and implemented a Smart Grid pilot program beginning in 2010 to demonstrate the viability of leveraging existing automated meter reading (“AMR”) deployments to provide much of the Smart Grid functionality of advanced metering infrastructure (“AMI”), but without the large capital investment that AMI rollouts typically entail. In particular, a central objective of the Smart Energy Pilot was to enable residential dynamic pricing (time-of-use “TOU” and critical peak rates and rebates) and two-way direct load control (“DLC”) by continually capturing AMR meter data transmissions and communicating through customer-sited broadband connections in conjunction with a standardsbased home area network (“HAN”). The pilot was supported by the U.S. Department of Energy’s (“DOE”) through the Smart Grid Demonstration program. NSTAR was very pleased to not only receive the funding support from DOE, but the guidance and support of the DOE throughout the pilot. NSTAR is also pleased to report to the DOE that it was able to execute and deliver a successful pilot on time and on budget. NSTAR looks for future opportunities to work with the DOE and others in future smart grid projects.

  17. The DOE Subsurface (SubTER) Initiative: Revolutionizing Responsible use of the Subsurface for Energy Production and Storage

    NASA Astrophysics Data System (ADS)

    Hubbard, S. S.; Walck, M. C.; Blankenship, D.; Bonneville, A.; Bromhal, G. S.; Daley, T. M.; Pawar, R.; Polsky, Y.; Mattson, E.; Mellors, R. J.

    2015-12-01

    The subsurface supplies more than 80% of the U.S.'s total energy needs through geothermal and hydrocarbon strategies and also provides vast potential for safe storage of CO2 and disposal of nuclear waste. Responsible and efficient use of the subsurface poses many challenges, many of which require the capability to monitor and manipulate sub-surface stress, fractures, and fluid flow at all scales. Adaptive control of subsurface fractures and flow is a multi-disciplinary challenge that, if achieved, has the potential to transform all subsurface energy strategies. As part of the U.S. Department of Energy's SubTER (Subsurface Technology and Engineering Research development and demonstration) initiative, a multi-National Laboratory team is developing next-generation approaches that will allow for adaptive control of subsurface fractures and flow. SubTER has identified an initial suite of technical thrust areas to focus work, and has initiated a number of small projects. This presentation will describe early progress associated with the SubTER technical topic areas of wellbore integrity, subsurface stress and induced seismicity, permeability manipulation and new subsurface signals. It will also describe SubTER plans, and provide a venue to solicit suggestions and discuss potential partnerships associated with future research directions.

  18. Subsurface structural mapping of Northern Nasser Lake region, Aswan, Egypt, using Bouguer data

    NASA Astrophysics Data System (ADS)

    Saleh, Salah

    2011-01-01

    In this study, we attempt to delineate the subsurface structures for the tectonic active region of Northern Nasser Lake using integrated interpretation techniques of gravity data with seismicity. The depths to the gravity sources, and the locations of the contacts of density contrast were estimated. Two methods were used for estimating source depths and contact locations: horizontal gradient (HG) and Euler deconvolution methods. Moreover, power spectral analysis, bandpass and upward continuation techniques were applied to evaluate the shallow and deep seated structures. Shallow depth structures were ranging between 0.30 km and 0.80 km. However, two average levels (interfaces) at depth 3.1 km and 7.2 km below the measuring level were revealed for the intermediate and deep seated structures respectively. Results of Euler deconvolution method suggested that, in the eastern part of the area, the basement could be observed on the ground and has become deeper in the central part. The interpreted structural map reveals that the area is affected by a set of faults trending mainly in the NW, E-W, N-S and NE-SW directions. Actually, this map has confirmed the idea that the intersections between the N-S and E-W striking faults along Nasser Lake area have generated seismic pulses. Moreover, three seismic zones (Z1, Z2 and Z3) are well correlated with the fault trends of the subsurface structures as derived from the horizontal gradient map. The present results suggest that there exist seismically-active fault east of High Dam, passing throughout Aswan reservoir from north to south. This fault is occupying region of high stress values which may generate large earthquakes in future, as it has long extension over several kilometers. Furthermore, the evaluated intruded volcanic bodies are found almost at the intersections between the E-W and NW oriented faults. Finally, the area is dissected by basement uplifts and troughs controlled mainly by the NW-SE faults.

  19. Tropical Indian Ocean subsurface temperature variability and the forcing mechanisms

    NASA Astrophysics Data System (ADS)

    Sayantani, Ojha; Gnanaseelan, C.

    2015-05-01

    The first two leading modes of interannual variability of sea surface temperature in the Tropical Indian Ocean (TIO) are governed by El Niño Southern Oscillation and Indian Ocean Dipole (IOD) respectively. TIO subsurface however does not co-vary with the surface. The patterns of the first mode of TIO subsurface temperature variability and their vertical structure are found to closely resemble the patterns of IOD and El Niño co-occurrence years. These co-occurrence years are characterized by a north-south subsurface dipole rather than a conventional IOD forced east-west dipole. This subsurface dipole is forced by wind stress curl anomalies, driven mainly by meridional shear in the zonal wind anomalies. A new subsurface dipole index (SDI) has been defined in this study to quantify the intensity of the north-south dipole mode. The SDI peaks during December to February (DJF), a season after the dipole mode index peaks. It is found that this subsurface north-south dipole is a manifestation of the internal mode of variability of the Indian Ocean forced by IOD but modulated by Pacific forcing. The seasonal evolution of thermocline, subsurface temperature and the corresponding leading modes of variability further support this hypothesis. Positive wind stress curl anomalies in the south and negative wind stress curl anomalies in the north of 5°S force (or intensify) downwelling and upwelling waves respectively during DJF. These waves induce strong subsurface warming in the south and cooling in the north (especially during DJF) and assist the formation and/or maintenance of the north-south subsurface dipole. A thick barrier layer forms in the southern TIO, supporting the long persistence of anomalous subsurface warming. To the best of our knowledge the existence of such north-south subsurface dipole in TIO is being reported for the first time.

  20. [Correlation of substrate structure and hydraulic characteristics in subsurface flow constructed wetlands].

    PubMed

    Bai, Shao-Yuan; Song, Zhi-Xin; Ding, Yan-Li; You, Shao-Hong; He, Shan

    2014-02-01

    The correlation of substrate structure and hydraulic characteristics was studied by numerical simulation combined with experimental method. The numerical simulation results showed that the permeability coefficient of matrix had a great influence on hydraulic efficiency in subsurface flow constructed wetlands. The filler with a high permeability coefficient had a worse flow field distribution in the constructed wetland with single layer structure. The layered substrate structure with the filler permeability coefficient increased from surface to bottom could avoid the short-circuited flow and dead-zones, and thus, increased the hydraulic efficiency. Two parallel pilot-scale constructed wetlands were built according to the numerical simulation results, and tracer experiments were conducted to validate the simulation results. The tracer experiment result showed that hydraulic characteristics in the layered constructed wetland were obviously better than that in the single layer system, and the substrate effective utilization rates were 0.87 and 0.49, respectively. It was appeared that numerical simulation would be favorable for substrate structure optimization in subsurface flow constructed wetlands.

  1. Hidden Markov models reveal complexity in the diving behaviour of short-finned pilot whales

    PubMed Central

    Quick, Nicola J.; Isojunno, Saana; Sadykova, Dina; Bowers, Matthew; Nowacek, Douglas P.; Read, Andrew J.

    2017-01-01

    Diving behaviour of short-finned pilot whales is often described by two states; deep foraging and shallow, non-foraging dives. However, this simple classification system ignores much of the variation that occurs during subsurface periods. We used multi-state hidden Markov models (HMM) to characterize states of diving behaviour and the transitions between states in short-finned pilot whales. We used three parameters (number of buzzes, maximum dive depth and duration) measured in 259 dives by digital acoustic recording tags (DTAGs) deployed on 20 individual whales off Cape Hatteras, North Carolina, USA. The HMM identified a four-state model as the best descriptor of diving behaviour. The state-dependent distributions for the diving parameters showed variation between states, indicative of different diving behaviours. Transition probabilities were considerably higher for state persistence than state switching, indicating that dive types occurred in bouts. Our results indicate that subsurface behaviour in short-finned pilot whales is more complex than a simple dichotomy of deep and shallow diving states, and labelling all subsurface behaviour as deep dives or shallow dives discounts a significant amount of important variation. We discuss potential drivers of these patterns, including variation in foraging success, prey availability and selection, bathymetry, physiological constraints and socially mediated behaviour. PMID:28361954

  2. Detection of microbial Life in the Subsurface

    NASA Astrophysics Data System (ADS)

    Stan-Lotter, H.; Fendrihan, S.; Dornmayr-Pfaffenhuemer, M.; Legat, A.; Gruber, C.; Weidler, G.; Gerbl, F.

    2007-08-01

    In recent years microbial communities were detected, which dwell in rocks, soil and caves deep below the surface of the Earth. This has led to a new view of the diversity of the terrestrial biosphere and of the physico-chemical boundaries for life. Two types of subterranean environments are Permo-Triassic salt sediments and thermal radioactive springs from igneous rocks in the Alps. Viable extremely halophilic archaea were isolated from ancient salt sediments which are estimated to be about 250 million years old (1). Chemotaxonomic and molecular characterization showed that they represent novel species, e. g. Halococcus salifodinae, Hcc. dombrowskiiand Halobacterium noricense. Simulation experiments with artificial halite suggested that these microorganisms probably survived while embedded in fluid inclusions. In the thermal springs, evidence for numerous novel microorganisms was found by 16S rDNA sequencing and probing for some metabolic genes; in addition, scanning electron microscopy of biofilms on the rock surfaces revealed great diversity of morphotypes (2). These communities appear to be active and growing, although their energy and carbon sources are entirely unknown. The characterization of subsurface inhabitants is of astrobiological relevance since extraterrestrial halite has been detected (3) and since microbial life on Mars, if existent, may have retreated into the subsurface. As a long-term goal, a thorough census of terrestrial microorganisms should be taken and their survival potential be determined in view of future missions for the search for extraterrestrial life, including planning precautions against possible forward contamination by space probes. (1) Fendrihan, S., Legat, A., Gruber, C., Pfaffenhuemer, M., Weidler, G., Gerbl, F., Stan-Lotter, H. (2006) Extremely halophilic archaea and the issue of long term microbial survival. Reviews in Environmental Science and Bio/technology 5, 1569-1605. (2) Weidler, G.W., Dornmayr-Pfaffenhuemer, M., Gerbl

  3. Effects of combining vertical and horizontal information into a primary flight display

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Nataupsky, Mark; Steinmetz, George G.

    1987-01-01

    A ground-based aircraft simulation study was conducted to determine the effects of combining vertical and horizontal flight information into a single display. Two display configurations were used in this study. The first configuration consisted of a Primary Flight Display (PFD) format and a Horizontal Situation Display (HSD) with the PFD displayed conventionally above the HSD. For the second display configuration, the HSD format was combined with the PFD format. Four subjects participated in this study. Data were collected on performance parameters, pilot-control inputs, auditory evoked response parameters (AEP), oculometer measurements (eye-scan), and heart rate. Subjective pilot opinion was gathered through questionnaire data and scorings for both the Subjective Workload Assessment Technique (SWAT) and the NASA Task Load Index (NASA-TLX). The results of this study showed that, from a performance and subjective standpoint, the combined configuration was better than the separate configuration. Additionally, both the eye-transition and eye-dwell times for the separate HSD were notably higher than expected, with a 46% increase in available visual time when going from double to single display configuration.

  4. Very-Heavy Sled Training for Improving Horizontal Force Output in Soccer Players.

    PubMed

    Morin, Jean-Benoît; Petrakos, George; Jimenez-Reyes, Pedro; Brown, Scott R; Samozino, Pierre; Cross, Matt R

    2016-11-11

    Sprint running acceleration is a key feature of physical performance in team sports, and recent literature shows that the ability to generate large magnitudes of horizontal ground reaction force and mechanical effectiveness of force application are paramount. We tested the hypothesis that very-heavy loaded sled sprint training would induce an improvement in horizontal force production, via an increased effectiveness of application. Training-induced changes in sprint performance and mechanical outputs were computed using a field method based on velocity-time data, before and after an 8-week protocol (16 sessions of 10x20-m sprints). 16 male amateur soccer players were assigned to either a very-heavy sled (80% body-mass sled load) or a control group (unresisted sprints). The main outcome of this pilot study is that very-heavy sled resisted sprint training, using much greater loads than traditionally recommended, clearly increased maximal horizontal force production compared to standard unloaded sprint training (effect size of 0.80 vs 0.20 for controls, unclear between-group difference) and mechanical effectiveness (i.e. more horizontally applied force; effect size of 0.95 vs -0.11, moderate between-group difference). In addition, 5-m and 20-m sprint performance improvement were moderate and small for the very-heavy sled group, and small and trivial for the control group, respectively. This brief report highlights the usefulness of very-heavy sled (80% body-mass) training, which may suggest value for practical improvement of mechanical effectiveness and maximal horizontal force capabilities in soccer players and other team sport athletes. This study may encourage further research to confirm the usefulness of very-heavy sled in this context.

  5. Investigation of the use of an electronic multifunction display and an electromechanical horizontal situation indicator for guidance and control of powered-lift short-haul aircraft

    NASA Technical Reports Server (NTRS)

    Clement, W. F.

    1976-01-01

    The use which pilots make of a moving map display from en route through the terminal area and including the approach and go-around flight phases was investigated. The content and function of each of three primary STOLAND displays are reviewed from an operational point of view. The primary displays are the electronic attitude director indicator (EADI), the horizontal situation indicator (HSI), and the multifunction display (MFD). Manually controlled flight with both flight director guidance and raw situation data is examined in detail in a simulated flight experiment with emphasis on tracking reference flight plans and maintaining geographic orientation after missed approaches. Eye-point-of-regard and workload measurements, coupled with task performance measurements, pilot opinion ratings, and pilot comments are presented. The experimental program was designed to offer a systematic objective and subjective comparison of pilots' use of the moving map MFD in conjunction with the other displays.

  6. Variability of soil potential for biodegradation of petroleum hydrocarbons in a heterogeneous subsurface.

    PubMed

    Kristensen, Andreas H; Poulsen, Tjalfe G; Mortensen, Lars; Moldrup, Per

    2010-07-15

    Quantifying the spatial variability of factors affecting natural attenuation of hydrocarbons in the unsaturated zone is important to (i) performing a reliable risk assessment and (ii) evaluating the possibility for bioremediation of petroleum-polluted sites. Most studies to date have focused on the shallow unsaturated zone. Based on a data set comprising analysis of about 100 soil samples taken in a 16 m-deep unsaturated zone polluted with volatile petroleum compounds, we statistically and geostatistically analysed values of essential soil properties. The subsurface of the site was highly layered, resulting in an accumulation of pollution within coarse sandy lenses. Air-filled porosity, readily available phosphorous, and the first-order rate constant (k(1)) of benzene obtained from slurry biodegradation experiments were found to depend on geologic sample characterization (P<0.05), while inorganic nitrogen was homogenously distributed across the soil stratigraphy. Semivariogram analysis showed a spatial continuity of 4-8.6 m in the vertical direction, while it was 2-5 times greater in the horizontal direction. Values of k(1) displayed strong spatial autocorrelation. Even so, the soil potential for biodegradation was highly variable, which from autoregressive state-space modeling was partly explained by changes in soil air-filled porosity and gravimetric water content. The results suggest considering biological heterogeneity when evaluating the fate of contaminants in the subsurface.

  7. Detection of Sub-Surface Water on Mars by Controlled and Natural Source Electromagnetic Induction

    NASA Technical Reports Server (NTRS)

    Connerney, J. E. P.; Acuna, M. H.

    2001-01-01

    Detection of subsurface liquid water on Mars is a leading scientific objective for Mars exploration in this decade. We describe electromagnetic induction (EM) methods that are both uniquely well suited for detection of subsurface liquid water on Mars and practical within the context of a Mars exploration program. EM induction methods are ideal for detection of more highly conducting (liquid water bearing) soils and rock beneath a more resistive overburden. A combined natural source and controlled source method offers an efficient and unambiguous characterization of the depth to liquid water and the extent of the aqueous region. The controlled source method employs an ac vertical dipole source (horizontal loop) to probe the depth to the conductor and a natural source method (gradient sounding) to characterize its conductivity-thickness product. These methods are proven in geophysical exploration and can be tailored to cope with any reasonable Mars crustal electrical conductivity. We describe a practical experiment and discuss experiment optimization to address the range of material properties likely encountered in the Mars crust.

  8. Effects of nutrient dosing on subsurface methanotrophic populations and trichloroethylene degradation.

    PubMed

    Pfiffner, S M; Palumbo, A V; Phelps, T J; Hazen, T C

    1997-01-01

    In in situ bioremediation demonstration at the Savannah River Site in Aiken, South Carolina, trichloroethyle degrading microorganisms were stimulated by delivering nutrients to the TCE-contaminated subsurface via horizontal injection wells. Microbial and chemical monitoring of groundwater from 12 vertical wells was used to examine the effects of methane and nutrient (nitrogen and phosphorus) dosing on the methanotrophic populations and on the potential of the subsurface microbial communities to degrade TCE. Densities of methanotrophs increased 3-5 orders of magnitude during the methane- and nutrient-injection phases; this increase coinclded with the higher methane levels observed in the monitoring wells. TCE degradation capacity, although not directly tied to methane concentration, responded to the methane injection, and responded more dramatically to the multiple-nutrient injection. tion. These results support the crucial role of methane, nitrogen, and phosphorus as amended nutrients in TCE bioremediation. The enhancing effects of nutrient dosing on microbial abundance and degradative potentials, coupled with increased chloride concentrations, provided multiple lines of evidence substantiating the effectiveness of this integrated in situ bioremediation process.

  9. Workshop Report on Deep Mars: Accessing the Subsurface of Mars on Near Term Missions

    NASA Technical Reports Server (NTRS)

    Langhoff, Stephanie R. (Editor)

    2008-01-01

    The workshop encompassed three major themes. The first theme was the scientific objectives of drilling, which center on the search for clues to the existence of past life and to the geological and climate history of Mars. Key questions are where and how deep to drill? Planetary protection issues were stressed as an important consideration in the design of any drilling mission. Secondly, architectures for drilling missions were discussed, including an overview of most of the current drills in operation that would be applicable to drilling on Mars. Considerable emphasis was placed on remote operation and drilling automation technologies. Finally, alternatives to conventional drilling were discussed. These included underground moles, penetrometers, horizontal drilling, impactors, and access to the subsurface from subsurface cavities. Considerable discussion centered on the possible Mars drilling missions that could be performed in both the near and longer term. The workshop participants concluded that useful science could be obtained today using low-cost impactors, with or without a sheperding spacecraft.

  10. Imaging the subsurface stratigraphy in the Ubehebe hydrovolcanic field (Death Valley, California) using ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Cagnoli, B.; Russell, J. K.

    2000-02-01

    Ground penetrating radar (GPR) surveys were carried out to collect subsurface images of the basaltic base surge deposits in the Ubehebe hydrovolcanic field, Death Valley National Park, California. Antennae with frequencies of 50, 100 and 200 MHz were used. This technique allowed the collection of useful geologic data, for example, the lower stratigraphic boundary of the pyroclastic deposits can be imaged and their thickness can be estimated. Different radar responses were also obtained from base surge deposits and underlying sedimentary rocks, which enable their recognition where no outcrops are available. Furthermore, GPR data confirmed the presence of small, eroded craters, which are partially filled by alluvium. In this case, an unconformity between the overlying, horizontally bedded alluvium and the underlying bowl-shaped base surge deposits can be recognized within the crater and the thickness of the alluvium estimated. Common mid-point (CMP) surveys suggested subsurface velocities of the electromagnetic waves in the upper part of these deposits between 0.095-0.1 m/ns.

  11. Subsurface faults detection based on magnetic anomalies investigation: A field example at Taba protectorate, South Sinai

    NASA Astrophysics Data System (ADS)

    Khalil, Mohamed H.

    2016-08-01

    Quantitative interpretation of the magnetic data particularly in a complex dissected structure necessitates using of filtering techniques. In Taba protectorate, Sinai synthesis of different filtering algorithms was carried out to distinct and verifies the subsurface structure and estimates the depth of the causative magnetic sources. In order to separate the shallow-seated structure, filters of the vertical derivatives (VDR), Butterworth high-pass (BWHP), analytic signal (AS) amplitude, and total horizontal derivative of the tilt derivative (TDR_THDR) were conducted. While, filters of the apparent susceptibility and Butterworth low-pass (BWLP) were conducted to identify the deep-seated structure. The depths of the geological contacts and faults were calculated by the 3D Euler deconvolution. Noteworthy, TDR_THDR was independent of geomagnetic inclination, significantly less susceptible to noise, and more sensitive to the details of the shallow superimposed structures. Whereas, the BWLP proved high resolution capabilities in attenuating the shorter wavelength of the near surface anomalies and emphasizing the longer wavelength derived from deeper causative structure. 3D Euler deconvolution (SI = 0) was quite amenable to estimate the depths of superimposed subsurface structure. The pattern, location, and trend of the deduced shallow and deep faults were conformed remarkably to the addressed fault system.

  12. Evaluation of wetting area and water distribution on different soils in subsurface drip irrigation emitters

    NASA Astrophysics Data System (ADS)

    Karimi, B.; Sohrabi, T.; Mirzaei, F.; Rodríguez-Sinobas, L.

    2012-04-01

    Growing pressure on the world's available water resources has led to an increase in the efficiency and productivity of water-use of irrigation systems in arid and semi-arid regions with water scarcity. In this context, sub-surface drip irrigation, where emitters discharge water underneath the soil surface, might help by saving water since soil evaporation, surface runoff, and deep percolation are greatly reduced or eliminated. In this paper, the wetting area and water distribution on light, medium and heavy texture homogeneous soils in subsurface drip irrigation emitters were evaluated. Experimental tests were carried out in a plexiglass lysimeter container with transparent walls. Emitters were buried at 15, 30 and 45 cm depths and discharge rates of 2 and 4 L/h were applied. Observations of wetting bulbs dimensions showed that water moved more laterally than downwards for higher emitter discharges. However, small emitter discharges enhanced water to move downwards. Likewise, higher emitter discharges also favored water to move upwards toward the soil surface. Water redistribution was affected by emitter depth. For the same emitter discharge, the deepest depth showed less water redistributed in the down vertical and horizontal directions but the contrary was observed for shallow depths. This could be explained considering the dry soil area above the emitter that is larger in the deepest emitters. Observations on wetting bulb dimensions and water distributions could aim at the selection of proper design variables (emitter depth), and/or operation variables (inlet head and irrigation time) in the studied soils under different scenarios of cropping patterns. Key Words: subsurface drip irrigation, wetting bulb, soil water distribution, water redistribution, optimum management

  13. Martian impact crater ejecta morphologies and their potential as indicators of subsurface volatile distribution

    NASA Technical Reports Server (NTRS)

    Barlow, Nadine G.

    1991-01-01

    Many martian impact craters ejecta morphologies suggestive of fluidization during ejecta emplacement. Impact into subsurface volatile reserviors (i.e., water, ice, CO2, etc.) is the mechanism favored by many scientists, although acceptance of this mechanism is not unanimous. In recent years, a number of studies were undertaken to better understand possible relationships between ejecta morphology and latitude, longitude, crater diameter, and terrain. These results suggest that subsurface volatiles do influence the formation of specific ejecta morphologies and may provide clues to the vertical and horizontal distribution of volatiles in more localized regions of Mars. The location of these volatile reservoirs will be important to humans exploring and settling Mars in the future. Qualitative descriptions of ejecta morphology and quantitative analyses of ejecta sinuosity and ejecta lobe areal extent from the basis of the studies. Ejecta morphology studies indicate that morphology is correlated with crater diameter and latitude, and, using depth-diameter relationships, these correlations strongly suggest that changes in morphology are related to transition among subsurface layers with varying amounts of volatiles. Ejecta sinuosity studies reveal correlations between degree of sinuosity (lobateness) and crater morphology, diameter, latitude, and terrain. Lobateness, together with variations in areal extent of the lobate ejecta blanket with morphology and latitude, probably depends most directly on the ejecta emplacement process. The physical parameters measured here can be compared with those predicted by existing ejecta emplacement models. Some of these parameters are best reproduced by models requiring incorporation of volatiles within the ejecta. However, inconsistencies between other parameters and the models indicate that more detailed modeling is necessary before the location of volatile reservoirs can be confidently predicted based on ejecta morphology studies

  14. Microbial field pilot study

    SciTech Connect

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  15. Air-water flow in subsurface systems

    NASA Astrophysics Data System (ADS)

    Hansen, A.; Mishra, P.

    2013-12-01

    Groundwater traces its roots to tackle challenges of safe and reliable drinking water and food production. When the groundwater level rises, air pressure in the unsaturated Vadose zone increases, forcing air to escape from the ground surface. Abnormally high and low subsurface air pressure can be generated when the groundwater system, rainfall, and sea level fluctuation are favorably combined [Jiao and Li, 2004]. Through this process, contamination in the form of volatile gases may diffuse from the ground surface into residential areas, or possibly move into groundwater from industrial waste sites. It is therefore crucial to understand the combined effects of air-water flow in groundwater system. Here we investigate theoretically and experimentally the effects of air and water flow in groundwater system.

  16. Optimal joule heating of the subsurface

    DOEpatents

    Berryman, James G.; Daily, William D.

    1994-01-01

    A method for simultaneously heating the subsurface and imaging the effects of the heating. This method combines the use of tomographic imaging (electrical resistance tomography or ERT) to image electrical resistivity distribution underground, with joule heating by electrical currents injected in the ground. A potential distribution is established on a series of buried electrodes resulting in energy deposition underground which is a function of the resistivity and injection current density. Measurement of the voltages and currents also permits a tomographic reconstruction of the resistivity distribution. Using this tomographic information, the current injection pattern on the driving electrodes can be adjusted to change the current density distribution and thus optimize the heating. As the heating changes conditions, the applied current pattern can be repeatedly adjusted (based on updated resistivity tomographs) to affect real time control of the heating.

  17. Repository Subsurface Preliminary Fire Hazard Analysis

    SciTech Connect

    Richard C. Logan

    2001-07-30

    This fire hazard analysis identifies preliminary design and operations features, fire, and explosion hazards, and provides a reasonable basis to establish the design requirements of fire protection systems during development and emplacement phases of the subsurface repository. This document follows the Technical Work Plan (TWP) (CRWMS M&O 2001c) which was prepared in accordance with AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''; Attachment 4 of AP-ESH-008, ''Hazards Analysis System''; and AP-3.11Q, ''Technical Reports''. The objective of this report is to establish the requirements that provide for facility nuclear safety and a proper level of personnel safety and property protection from the effects of fire and the adverse effects of fire-extinguishing agents.

  18. Solving subsurface structural problems using a computer

    SciTech Connect

    Witte, D.M. )

    1987-02-01

    Until recently, the solution of subsurface structural problems has required a combination of graphical construction, trigonometry, time, and patience. Recent advances in software available for both mainframe and microcomputers now reduce the time and potential error of these calculations by an order of magnitude. Software for analysis of deviated wells, three point problems, apparent dip, apparent thickness, and the intersection of two planes, as well as the plotting and interpretation of these data can be used to allow timely and accurate exploration or operational decisions. The available computer software provides a set of utilities, or tools, rather than a comprehensive, intelligent system. The burden for selection of appropriate techniques, computation methods, and interpretations still lies with the explorationist user.

  19. Joint inversion for mapping subsurface hydrologicalparameters

    SciTech Connect

    Tseng, Hung-Wen; Lee, Ki Ha

    2001-03-07

    Using electromagnetic (EM) and seismic travel time data and a least-square criteria, a two-dimensional joint inversion algorithm is under development to assess the feasibility of directly mapping subsurface hydrological properties in a crosswell setup. A simplified Archie's law combined with the time average equation relates the magnetic fields and seismic travel time to two hydrological parameters; rock porosity and pore fluid electrical conductivity. For simplicity, the hydrological parameter distributions are assumed to be two-dimensional. Preliminary results show that joint inversion does have better resolving power for the interpretation than using the EM method alone. Various inversion scenarios have been tested, and it has been found that alternately perturbing just one of the two parameters at each iteration gives the best data fit.

  20. Optimal joule heating of the subsurface

    DOEpatents

    Berryman, J.G.; Daily, W.D.

    1994-07-05

    A method for simultaneously heating the subsurface and imaging the effects of the heating is disclosed. This method combines the use of tomographic imaging (electrical resistance tomography or ERT) to image electrical resistivity distribution underground, with joule heating by electrical currents injected in the ground. A potential distribution is established on a series of buried electrodes resulting in energy deposition underground which is a function of the resistivity and injection current density. Measurement of the voltages and currents also permits a tomographic reconstruction of the resistivity distribution. Using this tomographic information, the current injection pattern on the driving electrodes can be adjusted to change the current density distribution and thus optimize the heating. As the heating changes conditions, the applied current pattern can be repeatedly adjusted (based on updated resistivity tomographs) to affect real time control of the heating.

  1. Microfluidic adhesion induced by subsurface microstructures.

    PubMed

    Majumder, Abhijit; Ghatak, Animangsu; Sharma, Ashutosh

    2007-10-12

    Natural adhesives in the feet of different arthropods and vertebrates show strong adhesion as well as excellent reusability. Whereas the hierarchical structures on the surface are known to have a substantial effect on adhesion, the role of subsurface structures such as the network of microchannels has not been studied. Inspired by these bioadhesives, we generated elastomeric layers with embedded air- or oil-filled microchannels. These adhesives showed remarkable enhancement of adhesion ( approximately 30 times), which results from the crack-arresting properties of the microchannels, together with the surface stresses caused by the capillary force. The importance of the thickness of the adhesive layer, channel diameter, interchannel spacing, and vertical position within the adhesive has been examined for developing an optimal design of this microfluidic adhesive.

  2. Microwave radiometer for subsurface temperature measurement

    NASA Technical Reports Server (NTRS)

    Porter, R. A.; Bechis, K. P.

    1976-01-01

    A UHF radiometer, operating at a frequency of 800 MHz, was modified to provide an integral, three frequency voltage standing wave ratio (VSWR) circuit in the radio frequency (RF) head. The VSWR circuit provides readings of power transmission at the antenna-material interface with an accuracy of plus or minus 5 percent. The power transmission readings are numerically equal to the emissivity of the material under observation. Knowledge of material emissivity is useful in the interpretation of subsurface apparent temperatures obtained on phantom models of biological tissue. The emissivities of phantom models consisting of lean beefsteak were found to lie in the range 0.623 to 0.779, depending on moisture content. Radiometric measurements performed on instrumented phantoms showed that the radiometer was capable of sensing small temperature changes occurring at depths of at least 19 to 30 mm. This is consistent with previously generated data which showed that the radiometer could sense temperatures at a depth of 38 mm.

  3. Armored Enzyme Nanoparticles for Remediation of Subsurface

    SciTech Connect

    Grate, Jay W.

    2005-09-01

    The remediation of subsurface contaminants is a critical problem for the Department of Energy, other government agencies, and our nation. Severe contamination of soil and groundwater exists at several DOE sites due to various methods of intentional and unintentional release. Given the difficulties involved in conventional removal or separation processes, it is vital to develop methods to transform contaminants and contaminated earth/water to reduce risks to human health and the environment. Transformation of the contaminants themselves may involve conversion to other immobile species that do not migrate into well water or surface waters, as is proposed for metals and radionuclides; or degradation to harmless molecules, as is desired for organic contaminants. Transformation of contaminated earth (as opposed to the contaminants themselves) may entail reductions in volume or release of bound contaminants for remediation.

  4. Physiologically anaerobic microorganisms of the deep subsurface

    SciTech Connect

    Stevens, S.E. Jr.; Chung, K.T.

    1992-06-01

    A variety of different media were used to isolate facultatively (FAB) and obligately anaerobic bacteria (OAB). These bacteria were isolated from core subsamples obtained from boreholes at the Idaho National Engineering Lab. (INEL) or at the Hanford Lab. (Yakima). Core material was sampled at various depths to 600 feet below the surface. All core samples with culturable bacteria contained at least FAB making thisthe most common physiological type of anaerobic bacteria present in the deep subsurface at these two sites. INEL core samples are characterized by isolates of both FAB and OAB. No isolates of acetogenic, methanogenic, or sulfate reducing bacteria were obtained. Yakima core samples are characterized by a marked predominance of FAB in comparison to OAB. In addition, isolates of acetogenic, methanogenic, and sulfate reducing bacteria were obtained. The Yakima site has the potential for complete anaerobic mineralization of organic compounds whereas this potential appears to be lacking at INEL.

  5. Letter report: Ari Patrinos -- Subsurface bioremediation

    SciTech Connect

    Happer, W.; MacDonald, G.J.; Ruderman, M.A.; Treiman, S.B.

    1995-07-26

    During the past summer, the authors had the opportunity to examine aspects of the remediation program of the Department of Energy (DOE). The most important conclusion that they have come to is that there is an urgent need to mount a comprehensive research program in remediation. It is also clear to them that DOE does not have the funding to carry out a program on the scale that is required. On the other hand, Environmental Management could very well fund such activities. They would hope that in the future there would be close collaboration between Environmental Management and Energy Research in putting together a comprehensive and well thought-out research program. Here, the authors comment on one aspect of remediation: subsurface bioremediation.

  6. Locating subsurface gravel with thermal imagery

    NASA Technical Reports Server (NTRS)

    Scholen, Douglas E.; Clerke, William H.; Luepke, Douglas E.

    1986-01-01

    A method was discussed for using 6 band thermal imagery to locate subsurface gravel deposits in vegetated areas. Geologic history is reviewed to select potential areas of study. An overflight was made using a thermal scanner. The data were processed with a computerized system to delineate areas showing a quartz signature radiated by a gravel deposit. The method was developed during a search for gravel on National Forest land in Louisiana. Processed data from thermal imagery was compared with known gravel deposits and exploratory drill hole logs. A high correlation was noted for a wide range of deposits, from commercial pits to trace deposits only a foot thick. Overburden at these sites varied from zero to sixty feet, near the maximum annual penetration by the thermal wave. It was concluded that the method can be used to locate buried gravel deposits and that more time and effort are needed to verify the usefulness for developing gravel pits adjacent to proposed construction sites.

  7. Examining the Magnetic Field Strength and the Horizontal and Vertical Motions in an Emerging Active Region

    NASA Astrophysics Data System (ADS)

    Lin, Chia-Hsien; Chen, Yu-Che

    2016-03-01

    Earlier observational studies have used the time evolution of emerging magnetic flux regions at the photosphere to infer their subsurface structures, assuming that the flux structure does not change significantly over the near-surface layer. In this study, we test the validity of this assumption by comparing the horizontal and vertical motions of an emerging active region. The two motions would be correlated if the emerging structure is rigid. The selected active region (AR) NOAA 11645 is not embedded in detectable preexisting magnetic field. The observed horizontal motion is quantified by the separation of the two AR polarities and the width of the region. The vertical motion is derived from the magnetic buoyancy theory. Our results show that the separation of the polarities is fastest at the beginning with a velocity of {≈ }4 Mm hr^{-1} and decreases to ≤ 1 Mm hr^{-1} after the main growing phase of flux emergence. The derived thick flux-tube buoyant velocity is between 1 and 3 Mm hr^{-1}, while the thin flux-tube approximation results in an unreasonably high buoyant velocity, consistent with the expectation that the approximation is inappropriate at the surface layer. The observed horizontal motion is not found to directly correlate with either the magnetic field strength or the derived buoyant velocities. However, the percentage of the horizontally oriented fields and the temporal derivatives of the field strength and the buoyant velocity show some positive correlations with the separation velocity. The results of this study imply that the assumption that the emerging active region is the cross section of a rising flux tube whose structure can be considered rigid as it rises through the near-surface layer should be taken with caution.

  8. Pilot selection and training

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1982-01-01

    Personality and situational factors relevant to individual and group performance in highly demanding environments, such as those faced by astronauts or by jet transport crew, are discussed. It is emphasized that although technical competence and proficiency in pilot selection are prerequisites for safety, operating a modern jet transport is a group endeavor that requires the effective coordination of the entire crew. A self-report test battery for measuring positive and negative personality traits of pilot candidates, termed the Personal Characteristics Inventory, is described.

  9. PILOT optical alignment

    NASA Astrophysics Data System (ADS)

    Longval, Y.; Mot, B.; Ade, P.; André, Y.; Aumont, J.; Baustista, L.; Bernard, J.-Ph.; Bray, N.; de Bernardis, P.; Boulade, O.; Bousquet, F.; Bouzit, M.; Buttice, V.; Caillat, A.; Charra, M.; Chaigneau, M.; Crane, B.; Crussaire, J.-P.; Douchin, F.; Doumayrou, E.; Dubois, J.-P.; Engel, C.; Etcheto, P.; Gélot, P.; Griffin, M.; Foenard, G.; Grabarnik, S.; Hargrave, P..; Hughes, A.; Laureijs, R.; Lepennec, Y.; Leriche, B.; Maestre, S.; Maffei, B.; Martignac, J.; Marty, C.; Marty, W.; Masi, S.; Mirc, F.; Misawa, R.; Montel, J.; Montier, L.; Narbonne, J.; Nicot, J.-M.; Pajot, F.; Parot, G.; Pérot, E.; Pimentao, J.; Pisano, G.; Ponthieu, N.; Ristorcelli, I.; Rodriguez, L.; Roudil, G.; Salatino, M.; Savini, G.; Simonella, O.; Saccoccio, M.; Tapie, P.; Tauber, J.; Torre, J.-P.; Tucker, C.

    2016-07-01

    PILOT is a balloon-borne astronomy experiment designed to study the polarization of dust emission in the diffuse interstellar medium in our Galaxy at wavelengths 240 μm with an angular resolution about two arcminutes. Pilot optics is composed an off-axis Gregorian type telescope and a refractive re-imager system. All optical elements, except the primary mirror, are in a cryostat cooled to 3K. We combined the optical, 3D dimensional measurement methods and thermo-elastic modeling to perform the optical alignment. The talk describes the system analysis, the alignment procedure, and finally the performances obtained during the first flight in September 2015.

  10. Evaluating the Effects of Horizontal Spatial Discretization on Interflow in the Soil Zone Using the Richards and Groundwater Flow Equations

    NASA Astrophysics Data System (ADS)

    Henson, W.; Niswonger, R. G.

    2011-12-01

    In many mountainous regions, a large proportion of streamflow originates as shallow subsurface storm flow (interflow) within the shallow soils of hillslopes. Infiltration can accumulate to form perched groundwater within the upper few meters of the soil horizon that drains to streams through both macropores and soil-matrix. Richards Equation has become a commonly used governing equation for simulating interflow in regional-scale models. Recent research has shown that optimal vertical discretization for Richards Equation near land surface and the water table is much smaller than the discretization typically used in basin-scale hydrologic models, yet little is known about optimal horizontal discretization or potential effects of horizontal discretization on interflow solutions. Most of the work related to the effects of discretization on the solution of Richards Equation has focused on the vertical infiltration problem. This study evaluates horizontal spatial discretization effects on interflow predictions using 1) a modified version of GSFLOW and 2) VS2DT. The modified GSFLOW couples Smith-Parlange 1-D infiltration equations with 3-D unconfined groundwater flow equation, whereas VS2DT uses Richards Equation to represent infiltration and variably saturated flow. Interflow solutions and breakthrough at the stream were compared using a model domain similar to Vauclin and others (1979) with horizontal grid resolutions ranging from 0.05-5m and vertical resolutions ranging between 0.05-1m, with horizontal flow path lengths of 25m to the stream. Variable horizontal spatial resolutions affected VS2DT interflow solutions (RMSE up to 0.12) and interflow breakthrough at the stream, whereas GSFLOW solutions were well correlated (RMSE <0.052). Interflow breakthrough was delayed by up to 10 days with increasing resolution in VS2DT, whereas GSFLOW breakthrough was consistently the same day. Results indicate that the solution of Richards Equation for soil-zone interflow is much

  11. Subsurface Controls on Habitability of Hydrothermal Waters

    NASA Astrophysics Data System (ADS)

    Fristad, K. E.; Som, S. M.; Hoehler, T. M.

    2014-12-01

    Liquid water alone does not make an environment habitable. Environmental settings dominated by water-rock reactions such as in hydrothermal vents and springs are natural targets for astrobiological investigation of waterworlds because the rich geochemical diversity at these locales provides abundant energy in solvent to support microbial life. Hydrogen oxidizers are of particular interest because H2-based metabolisms are widespread and deeply rooted throughout the phylogenetic tree of life, implying they may have emerged extremely early in the evolution, and possibly even the origin, of life on Earth and potentially any other rocky bodies bearing liquid water. Dihydrogen (H2) can be lithogenically produced by the hydrolytic oxidation of the ferrous iron component in Fe-bearing minerals as well as by radiolytic cleavage of water by α, β, or γ radiation produced during the decay of radioactive isotopes. Lithogenic H2 production mechanisms operate across a range of rock types, but the concentration of dissolved H2 available to life is controlled by a number of subsurface factors such as surface geometry, water to rock ratio, production rate, and fluid flux. These factors are often controlled by the larger geologic and structural context of a particular site. We present results of an ongoing project that surveys H2 concentrations from terrestrial hydrothermal waters in diverse chemical and physical settings. Aqueous H2 concentrations and potential subsurface controls are presented for sites across the western U.S. including Yellowstone National Park, Lassen Volcanic National Park, and Iceland. In coordination with field data, we also investigate the habitability of various sites numerically by coupling a geochemical model of water-rock interaction with that of single-cell methanogenesis and compute a habitability index for the given environment. In particular, we investigate the control that temperature, rock composition, water composition, and water to rock ratio

  12. Imaging the Subsurface with Upgoing Muons

    NASA Astrophysics Data System (ADS)

    Bonal, N.; Preston, L. A.; Schwellenbach, D.; Dreesen, W.; Green, A.

    2014-12-01

    We assess the feasibility of imaging the subsurface using upgoing muons. Traditional muon imaging focuses on more-prevalent downgoing muons. Muons are subatomic particles capable of penetrating the earth's crust several kilometers. Downgoing muons have been used to image the Pyramid of Khafre of Giza, various volcanoes, and smaller targets like cargo. Unfortunately, utilizing downgoing muons requires below-target detectors. For aboveground objects like a volcano, the detector is placed at the volcano's base and the top portion of the volcano is imaged. For underground targets like tunnels, the detector would have to be placed below the tunnel in a deeper tunnel or adjacent borehole, which can be costly and impractical for some locations. Additionally, detecting and characterizing subsurface features like voids from tunnels can be difficult. Typical characterization methods like sonar, seismic, and ground penetrating radar have shown mixed success. Voids have a marked density contrast with surrounding materials, so using methods sensitive to density variations would be ideal. High-energy cosmic ray muons are more sensitive to density variation than other phenomena, including gravity. Their absorption rate depends on the density of the materials through which they pass. Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and detector, much like a CAT scan. Currently, tomography using downgoing muons can resolve features to the sub-meter scale. We present results of exploratory work, which demonstrates that upgoing muon fluxes appear sufficient to achieve target detection within a few months. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Accelerating Subsurface Transport Simulation on Heterogeneous Clusters

    SciTech Connect

    Villa, Oreste; Gawande, Nitin A.; Tumeo, Antonino

    2013-09-23

    Reactive transport numerical models simulate chemical and microbiological reactions that occur along a flowpath. These models have to compute reactions for a large number of locations. They solve the set of ordinary differential equations (ODEs) that describes the reaction for each location through the Newton-Raphson technique. This technique involves computing a Jacobian matrix and a residual vector for each set of equation, and then solving iteratively the linearized system by performing Gaussian Elimination and LU decomposition until convergence. STOMP, a well known subsurface flow simulation tool, employs matrices with sizes in the order of 100x100 elements and, for numerical accuracy, LU factorization with full pivoting instead of the faster partial pivoting. Modern high performance computing systems are heterogeneous machines whose nodes integrate both CPUs and GPUs, exposing unprecedented amounts of parallelism. To exploit all their computational power, applications must use both the types of processing elements. For the case of subsurface flow simulation, this mainly requires implementing efficient batched LU-based solvers and identifying efficient solutions for enabling load balancing among the different processors of the system. In this paper we discuss two approaches that allows scaling STOMP's performance on heterogeneous clusters. We initially identify the challenges in implementing batched LU-based solvers for small matrices on GPUs, and propose an implementation that fulfills STOMP's requirements. We compare this implementation to other existing solutions. Then, we combine the batched GPU solver with an OpenMP-based CPU solver, and present an adaptive load balancer that dynamically distributes the linear systems to solve between the two components inside a node. We show how these approaches, integrated into the full application, provide speed ups from 6 to 7 times on large problems, executed on up to 16 nodes of a cluster with two AMD Opteron 6272

  14. 10 CFR 39.45 - Subsurface tracer studies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.45 Subsurface tracer studies. (a) The licensee shall require all personnel handling...

  15. 10 CFR 39.45 - Subsurface tracer studies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.45 Subsurface tracer studies. (a) The licensee shall require all personnel handling...

  16. 10 CFR 39.45 - Subsurface tracer studies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.45 Subsurface tracer studies. (a) The licensee shall require all personnel handling...

  17. 10 CFR 39.45 - Subsurface tracer studies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.45 Subsurface tracer studies. (a) The licensee shall require all personnel handling...

  18. 10 CFR 39.45 - Subsurface tracer studies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.45 Subsurface tracer studies. (a) The licensee shall require all personnel handling...

  19. Subsurface Mapping: A Question of Position and Interpretation

    ERIC Educational Resources Information Center

    Kellie, Andrew C.

    2009-01-01

    This paper discusses the character and challenges inherent in the graphical portrayal of features in subsurface mapping. Subsurface structures are, by their nature, hidden and must be mapped based on drilling and/or geophysical data. Efficient use of graphical techniques is central to effectively communicating the results of expensive exploration…

  20. The distribution of subsurface damage in fused silica

    SciTech Connect

    Miller, P E; Suratwala, T I; Wong, L L; Feit, M D; Menapace, J A; Davis, P J; Steele, R A

    2005-11-21

    Managing subsurface damage during the shaping process and removing subsurface damage during the polishing process is essential in the production of low damage density optical components, such as those required for use on high peak power lasers. Removal of subsurface damage, during the polishing process, requires polishing to a depth which is greater than the depth of the residual cracks present following the shaping process. To successfully manage, and ultimately remove subsurface damage, understanding the distribution and character of fractures in the subsurface region introduced during fabrication process is important. We have characterized the depth and morphology of subsurface fractures present following fixed abrasive and loose abrasive grinding processes. At shallow depths lateral cracks and an overlapping series of trailing indentation fractures were found to be present. At greater depths, subsurface damage consists of a series of trailing indentation fractures. The area density of trailing fractures changes as a function of depth, however the length and shape of individual cracks remain nearly constant for a given grinding process. We have developed and applied a model to interpret the depth and crack length distributions of subsurface surface damage in terms of key variables including abrasive size and load.

  1. DEMONSTRATION BULLETIN: SUBSURFACE VOLATILIZATION AND VENTILATION SYSTEM - BROWN & ROOT ENVIRONMENTAL

    EPA Science Inventory

    The Subsurface Volatilization and Ventilation System (SVVS*) is an in-situ vacuum extraction/air sparging and bioremediation technology for the treatment of subsurface organic contamination in soil and groundwater. The technology, developed by Billings and Associates, Inc., and o...

  2. Water and nitrogen requirements of subsurface drip irrigated pomegranate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface drip irrigation is a well-developed practice for both annual and perennial crops. The use of subsurface drip is a well-established practice in many annual row crops, e.g. tomatoes, strawberries, lettuce. However, the use of subsurface drip on perennial crops has been slow to develop. With th...

  3. 75 FR 1276 - Requirements for Subsurface Safety Valve Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-11

    ... Equipment AGENCY: Minerals Management Service (MMS), Interior. ACTION: Final rule. SUMMARY: The MMS is... Subsurface Safety Valve Equipment (API Spec 14A) into its regulations. The MMS is incorporating the Eleventh.../API Specification 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition,...

  4. Subsurface banding poultry litter impacts greenhouse gas emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact subsurface banding poultry litter (PL) has on greenhouse gas emissions is limited. Thus, a study was conducted in established bermudagrass pastures located in Coastal Plain and Piedmont regions to determine the effects subsurface applying PL has on soil flux using two different band spaci...

  5. Articulating Support for Horizontal Resistive Exercise

    NASA Technical Reports Server (NTRS)

    Gundo, Daniel; Schaffner, Grant; Bentley, Jason; Loehr, James A.

    2005-01-01

    A versatile mechanical device provides support for a user engaged in any of a variety of resistive exercises in a substantially horizontal orientation. The unique features and versatility of the device promise to be useful in bedrest studies, rehabilitation, and specialized strength training. The device affords a capability for selectively loading and unloading of portions of the user s body through its support mechanisms, so that specific parts of the body can be trained with little or no effect on other parts that may be disabled or in the process of recovery from injury. Thus, the device is ideal for rehabilitation exercise programs prescribed by physicians and physical therapists. The capability for selective loading and support also offers potential benefits to strength and conditioning trainers and athletes who wish to selectively strengthen selected parts. The principal innovative aspect of the device is that it supports the subject s weight while enabling the subject, lying substantially horizontally, to perform an exercise that closely approximates a full standing squat. The device includes mechanisms that support the subject in such a way that the hips are free to translate both horizontally and vertically and are free to rotate about the line connecting the hips. At the same time, the shoulders are free to translate horizontally while the upper back is free to rotate about the line connecting the shoulders. Among the mechanisms for hip motion and support is a counterbalance that offsets the weight of the subject as the subject s pelvis translates horizontally and vertically and rotates the pelvis about the line connecting the hips. The counterbalance is connected to a pelvic support system that allows these pelvic movements. The subject is also supported at the shoulder by a mechanism that can tilt to provide continuous support of the upper back while allowing the rotation required for arching the back as the pelvis is displaced. The shoulder support

  6. General Aviation Pilot Education Program.

    ERIC Educational Resources Information Center

    Cole, Warren L.

    General Aviation Pilot Education (GAPE) was a safety program designed to improve the aeronautical education of the general aviation pilot in anticipation that the national aircraft accident rate might be improved. GAPE PROGRAM attempted to reach the average general aviation pilot with specific and factual information regarding the pitfalls of his…

  7. Single-Pilot Workload Management

    NASA Technical Reports Server (NTRS)

    Rogers, Jason; Williams, Kevin; Hackworth, Carla; Burian, Barbara; Pruchnicki, Shawn; Christopher, Bonny; Drechsler, Gena; Silverman, Evan; Runnels, Barry; Mead, Andy

    2013-01-01

    Integrated glass cockpit systems place a heavy cognitive load on pilots (Burian Dismukes, 2007). Researchers from the NASA Ames Flight Cognition Lab and the FAA Flight Deck Human Factors Lab examined task and workload management by single pilots. This poster describes pilot performance regarding programming a reroute while at cruise and meeting a waypoint crossing restriction on the initial descent.

  8. Recovery of bypassed oil in the Dundee formation using horizontal drains. Quarterly progress report, October 1, 1995--December 31, 1995

    SciTech Connect

    Wood, J.R.

    1996-01-29

    The principal objective of this project is to demonstrate the feasibility and economic success of producing oil from abandoned or nearly abandoned fields in the Dundee Formation of Central Michigan using horizontal drilling technology. A site for a horizontal well was selected in Crystal Field, a nearly-abandoned Dundee oil field in Michigan. This field had produced over 8 million barrels of oil, mostly in the 1930`s and 1940`s. At the height of development, Crystal Field produced from 193 wells, but by 1995, only seven producing wells remained, each producing less than 10 bbls/day. A horizontal well was drilled as a field demonstration pilot, funded through this DOE project, and was immensely successful. Core and logs from the Dundee interval were recovered from a vertical borehole at the same surface location. The horizontal well was brought on production at a rate of 100 bbls/day and is probably capable of producing at a higher rate. The addition of several horizontal wells, similar to the demonstration well, will likely add another 2 million bbls (or more) to the cumulative production of the field over the next few years. The presence of untapped oil in this Dundee field was dramatically demonstrated and the favorable economics were made clearly evident. If other abandoned Dundee fields are re-developed in a similar manner, the additional oil produced domestically will probably be about 80 to 100 million bbls.

  9. Horizontal modular dry irradiated fuel storage system

    DOEpatents

    Fischer, Larry E.; McInnes, Ian D.; Massey, John V.

    1988-01-01

    A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

  10. Stability of vertical and horizontal axis Levitrons

    NASA Astrophysics Data System (ADS)

    Michaelis, M. M.; Taylor, D. B.

    2015-11-01

    The stability of the new horizontal axis Levitron3 is compared with that of the vertical axis device. The rotation frequency ranges are similar because they are determined by the same precessional micro-trap, for which some theory is given. But the macro-trap of the horizontal axis system gives it far greater mechanical stability. Field-line studies allow this to be more easily visualized. The greater stability allows for educational experiments which could only be contemplated with the old Levitron: driven precession and nutation and motion along the field lines. These experiments illustrate some very fundamental space dynamics and several other topics. The enhanced stability may also lead to electro-mechanical applications.

  11. Kinematics of horizontal and vertical caterpillar crawling.

    PubMed

    van Griethuijsen, Linnea I; Trimmer, Barry A

    2009-05-01

    Unlike horizontal crawling, vertical crawling involves two counteracting forces: torque rotating the body around its center of mass and gravity resisting forward movement. The influence of these forces on kinematics has been examined in the soft-bodied larval stage of Manduca sexta. We found that crawling and climbing are accomplished using the same movements, with both segment timing and proleg lift indistinguishable in horizontal and vertical locomotion. Minor differences were detected in stride length and in the delay between crawls, which led to a lower crawling speed in the vertical orientation. Although these differences were statistically significant, they were much smaller than the variation in kinematic parameters between animals. The ability of Manduca to crawl and climb using the same movements is best explained by Manduca's relatively small size, slow speed and strong, controlled, passive grip made possible by its proleg/crochets.

  12. Film condensation in a horizontal rectangular duct

    NASA Technical Reports Server (NTRS)

    Lu, Qing; Suryanarayana, N. V.

    1993-01-01

    Condensation heat transfer in a horizontal rectangular duct was experimentally and analytically investigated. To prevent the dripping of condensate on the film, the experiment was conducted inside a horizontal rectangular duct with vapor condensing only on the bottom cooled plate of the duct. R-113 and FC-72 (Fluorinert Electronic Fluid developed by the 3M Company) were used as the condensing fluids. The experimental program included measurements of film thickness, local and average heat transfer coefficients, wave length, wave speed, and a study of wave initiation. The measured film thickness was used to obtain the local heat transfer coefficient. The wave initiation was studied both with condensation and with an adiabatic air-liquid flow. The test sections used in both experiments were identical.

  13. Developing Ocean Subsurface Data Record from CALIPSO Depolarization Ratio Measurements

    NASA Astrophysics Data System (ADS)

    Hu, Y.; Rodier, S. D.; Zhai, P.; Josset, D. B.; Omar, A. H.

    2012-12-01

    CALIOP, the dual wavelength, polarization sensitive lidar flying aboard the CALIPSO satellite, has been operating since June 2006 and is expected to continue for several more years. CALIOP's depolarization ratio is one of the best calibrated measurements made by the A-Train sensors. Over the life of the CALIPSO mission, the stability of the CALIOP depolarization ratio calibration has remained within 1%. CALIOP's depolarization ratio measurements can be used for studying changes in the backscatter of ocean subsurface particulates. The ocean surface/subsurface depolarization ratio measurements from CALIOP together with collocated A-train instruments can be used for estimating the subsurface particulate backscatter coefficient (bbp) and the cross polarization component of the column integrated ocean subsurface backscatter signal. To derive the cross component of inte¬grated ocean subsurface backscatter signal from the depolarization ratio of CALIOP integrated ocean surface/subsurface range bins, we need theoretical estimates of the ocean surface back¬scatter cross section, which can be derived accurately from CloudSat ocean surface backscatter measurements or from AMSR-E wind speeds. Using the CALIOP cross component of the integrated ocean subsurface backscatter together with diffuse attenuation coefficient derived from MODIS, bbp can be estimated. Preliminary CALIOP data analysis shows that in the Southern Oceans, ocean subsurface backscatter has increased by about 5% since the beginning of the CALIPSO mission in June 2006. This study will: (1) introduce the CALIPSO ocean subsurface backscatter data products; (2) assess the uncertainties in the data products and comparing with in situ optics measurements, radiative transfer modeling and aircraft lidar measurements; and (3) summarize the global and regional (e.g., Gulf of Mexico region) statistics and temporal variations of the ocean subsurface backscatter from CALIPSO measurements.

  14. Natural Convection Above A Horizontal Heat Source

    DTIC Science & Technology

    1993-03-01

    surface was a thermochromic liquid crystal (TLC) sheet. Used to ensure a smooth flat surface, the sheet also provided a visualization of the temperature...a flat horizontal heated surface surrounded by an unheated area. This can contribute significantly to studies in liquid immersion cooling...Gebhart, B., "The Transition of Plane Plumes," Int. J. Heat Mass Transfer, v.18., pp. 513-526, 1975. 13. Gaiser, A.O., "Natural Convection Liquid

  15. Management of horizontally impacted dilacerated lateral incisor

    PubMed Central

    Katta, Anil Kumar; Peddu, Revathi; Vannala, Venkataramana; Dasari, Vaishnavi

    2015-01-01

    Impaction of maxillary lateral incisor with odontome and retained deciduous tooth is not often seen in regular dental practice. Impaction of anterior teeth cause generalized spacing which affects the esthetics of the face. Here we report a case of an 18-year-old patient with horizontally impacted dilacerated lateral incisor, which was bought into occlusion with the help of orthodontic tooth movement within a span of 18 months. PMID:26538954

  16. Horizontal drilling in shallow, geologically complex reservoirs

    SciTech Connect

    Venable, S.D.

    1992-10-01

    The objective of this project is to test the concept that multiple hydraulic fracturing from a directionally-drilled horizontal well, using the medium radius build rate method, can increase gas production sufficiently to justify economic viability over conventional stimulated vertical wells. The test well is located in Yuma County, Colorado, in a favorable area of established production to avoid exploration risks. This report presents: background information; project description which covers location selection/geologic considerations; and preliminary work plan. (AT)

  17. Horizontal-parallax-only electronic holography

    NASA Astrophysics Data System (ADS)

    Poon, T.-C.; Akin, T.; Indebetouw, G.; Kim, T.

    2005-04-01

    The principle of optical scanning holography (OSH) is proposed to acquire horizontal-parallax-only (HPO) holographic information electronically. We first briefly summarize the results of OSH and then discuss how HPO-electronic holographic information can be acquired using OSH. Finally we provide simulations to illustrate and clarify the proposed idea. Although many ideas of HPO-holography have been proposed and studied, to the best of our knowledge, this is the first proposed electronic technique to acquire HPO-holographic information.

  18. Spin stabilized magnetic levitation of horizontal rotors.

    SciTech Connect

    Romero, Louis Anthony

    2004-10-01

    In this paper we present an analysis of a new configuration for achieving spin stabilized magnetic levitation. In the classical configuration, the rotor spins about a vertical axis; and the spin stabilizes the lateral instability of the top in the magnetic field. In this new configuration the rotor spins about a horizontal axis; and the spin stabilizes the axial instability of the top in the magnetic field.

  19. Search for horizontal bosons at the SSC

    SciTech Connect

    Albright, C.H.; Deshpande, N.G.; Gunion, J.F.; Haber, H.E.

    1984-01-01

    The production process anti p p ..-->.. l/sup -/l'/sup +/ + X, where the leptons belong to two different generations and X refers to spectator jets, provides a clear signature for horizontal (generation-changing) bosons when the leptons are emitted nearly back-to-back and p/sub T//sup miss/ = 0. Cross sections and p/sub T/ distributions for each lepton are presented, and discovery limits on M/sub H/ are extracted for several different channels.

  20. Continuity of subsurface fault structure revealed by gravity anomaly: the eastern boundary fault zone of the Niigata plain, central Japan

    NASA Astrophysics Data System (ADS)

    Wada, Shigeki; Sawada, Akihiro; Hiramatsu, Yoshihiro; Matsumoto, Nayuta; Okada, Shinsuke; Tanaka, Toshiyuki; Honda, Ryo

    2017-01-01

    We have investigated gravity anomalies around the Niigata plain, which is a sedimentary basin in central Japan bounded by mountains, to examine the continuity of subsurface fault structures of a large fault zone—the eastern boundary fault zone of the Niigata plain (EBFZNP). The features of the Bouguer anomaly and its first horizontal and vertical derivatives clearly illustrate the EBFZNP. The steep first horizontal derivative and the zero isoline of the vertical derivative are clearly recognized along the entire EBFZNP over an area that shows no surface topographic features of an active fault. Two-dimensional density structure analyses also confirm a relationship between the two first derivatives and the subsurface fault structure. Therefore, we conclude that the length of the EBFZNP as an active fault extends to 56 km, which is longer than previously estimated. This length leads to an estimation of a moment magnitude of 7.4 of an expected earthquake from the EBFZNP.[Figure not available: see fulltext.

  1. Bayesian model selection in hydrogeophysics: Application to conceptual subsurface models of the South Oyster Bacterial Transport Site, Virginia, USA

    NASA Astrophysics Data System (ADS)

    Brunetti, Carlotta; Linde, Niklas; Vrugt, Jasper A.

    2017-04-01

    Geophysical data can help to discriminate among multiple competing subsurface hypotheses (conceptual models). Here, we explore the merits of Bayesian model selection in hydrogeophysics using crosshole ground-penetrating radar data from the South Oyster Bacterial Transport Site in Virginia, USA. Implementation of Bayesian model selection requires computation of the marginal likelihood of the measured data, or evidence, for each conceptual model being used. In this paper, we compare three different evidence estimators, including (1) the brute force Monte Carlo method, (2) the Laplace-Metropolis method, and (3) the numerical integration method proposed by Volpi et al. (2016). The three types of subsurface models that we consider differ in their treatment of the porosity distribution and use (a) horizontal layering with fixed layer thicknesses, (b) vertical layering with fixed layer thicknesses and (c) a multi-Gaussian field. Our results demonstrate that all three estimators provide equivalent results in low parameter dimensions, yet in higher dimensions the brute force Monte Carlo method is inefficient. The isotropic multi-Gaussian model is most supported by the travel time data with Bayes factors that are larger than 10100 compared to conceptual models that assume horizontal or vertical layering of the porosity field.

  2. A pilot training manual for the terminal configured vehicle electronic horizontal situation indicator

    NASA Technical Reports Server (NTRS)

    Houck, J. A.

    1981-01-01

    The initial phase of a training program for the Terminal Configured Vehicle Electronic Situation indicator (EHSI) is presented. The EHSI and its symbology is introduced and interpretation of the symbols is explained. Basic symbols shown on the display at all times are first presented. Additional optional symbols to be used as appropriate during different portions of a flight are then introduced and various display configurations interpreted. The upper half of each page is a reproduction of the EHSI display or other pertinent instructional material and the bottom half contains explanatory text, simplifying production of an audiovisual package for use with large training classes. Two quizzes on the course material are included.

  3. Horizontal transmission of streptococcus mutans in schoolchildren

    PubMed Central

    Castillo, Ana M.; Liébana, Maria J.; Castillo, Francisca; Martín-Platero, Antonio; Liébana, José

    2012-01-01

    Objetive: The aim of this study was to analyze possible horizontal transmission patterns of S. mutans among 6-7-yr-old schoolchildren from the same class, identifying genotypes and their diversity and relationship with caries disease status. Study Design: Caries indexes and saliva mutans streptococci and lactobacilli counts were recorded in 42 schoolchildren. Mutans streptococci colonies were identified by means of biochemical tests and all S. mutans strains were genotyped by arbitrarily primed polymerase chain reaction. A child was considered free of S. mutans when it could not be isolated in 3 samples at 1-week intervals. Results: S. mutans was isolated in 30 schoolchildren: 20 having one genotype and 10 two genotypes. Higher mutans streptococci and caries index values were found in those with two genotypes. Five genotypes were isolated in more than 1 schoolchild and one of these was isolated in 3 schoolchildren. Our results suggest that horizontal transmission may take place. Conclusion: Schoolchildren aged 6-7 yrs may be the source of mutual transmission of S. mutans. Key words:Streptococcus mutans, Horizontal transmission, AP-PCR, genotyping PMID:22143733

  4. Vertical and horizontal seismometric observations of tides

    NASA Astrophysics Data System (ADS)

    Lambotte, S.; Rivera, L.; Hinderer, J.

    2006-01-01

    Tidal signals have been largely studied with gravimeters, strainmeters and tiltmeters, but can also be retrieved from digital records of the output of long-period seismometers, such as STS-1, particularly if they are properly isolated. Horizontal components are often noisier than the vertical ones, due to sensitivity to tilt at long periods. Hence, horizontal components are often disturbed by local effects such as topography, geology and cavity effects, which imply a strain-tilt coupling. We use series of data (duration larger than 1 month) from several permanent broadband seismological stations to examine these disturbances. We search a minimal set of observable signals (tilts, horizontal and vertical displacements, strains, gravity) necessary to reconstruct the seismological record. Such analysis gives a set of coefficients (per component for each studied station), which are stable over years and then can be used systematically to correct data from these disturbances without needing heavy numerical computation. A special attention is devoted to ocean loading for stations close to oceans (e.g. Matsushiro station in Japon (MAJO)), and to pressure correction when barometric data are available. Interesting observations are made for vertical seismometric components; in particular, we found a pressure admittance between pressure and data 10 times larger than for gravimeters for periods larger than 1 day, while this admittance reaches the usual value of -3.5 nm/s 2/mbar for periods below 3 h. This observation may be due to instrumental noise, but the exact mechanism is not yet understood.

  5. ISOE Pilot Project Update

    SciTech Connect

    D. A. Hagemeyer D. E. Lewis

    2012-05-05

    This slide show introduces the Pilot Project to increase the value of Information System on Occupational Exposure (ISOE) data by increasing participation and amount of data reported from the U.S., reduce the hurdles and effort in participating, streamline the process of reporting and reduce time delay, and eliminate data entry and redundant effort.

  6. Telescience Testbed Pilot Program

    NASA Technical Reports Server (NTRS)

    Gallagher, Maria L. (Editor); Leiner, Barry M. (Editor)

    1988-01-01

    The Telescience Testbed Pilot Program is developing initial recommendations for requirements and design approaches for the information systems of the Space Station era. During this quarter, drafting of the final reports of the various participants was initiated. Several drafts are included in this report as the University technical reports.

  7. Pilot-Wave Hydrodynamics

    NASA Astrophysics Data System (ADS)

    Bush, John W. M.

    2015-01-01

    Yves Couder, Emmanuel Fort, and coworkers recently discovered that a millimetric droplet sustained on the surface of a vibrating fluid bath may self-propel through a resonant interaction with its own wave field. This article reviews experimental evidence indicating that the walking droplets exhibit certain features previously thought to be exclusive to the microscopic, quantum realm. It then reviews theoretical descriptions of this hydrodynamic pilot-wave system that yield insight into the origins of its quantum-like behavior. Quantization arises from the dynamic constraint imposed on the droplet by its pilot-wave field, and multimodal statistics appear to be a feature of chaotic pilot-wave dynamics. I attempt to assess the potential and limitations of this hydrodynamic system as a quantum analog. This fluid system is compared to quantum pilot-wave theories, shown to be markedly different from Bohmian mechanics and more closely related to de Broglie's original conception of quantum dynamics, his double-solution theory, and its relatively recent extensions through researchers in stochastic electrodynamics.

  8. The role of fragipan soils properties for hillslope subsurface flow dynamics

    NASA Astrophysics Data System (ADS)

    Dahlke, Helen; Easton, Zachary; Brown, Larry; Steenhuis, Tammo

    2010-05-01

    In watersheds characterized by fragipan, soils runoff generation is traditionally assumed to be dominated by shallow subsurface flow perched by a nearly impenetrable, low-conductive, subsurface soil horizon. However, several irrigation studies have indicated that fragipan soils can conduct subsurface flow vertically in considerable amounts resulting from differences in fragipan properties (e.g., prism diameter, interprism cracks, etc). These fragipan properties remain difficult to measure at the hillslope and watershed scales and consequently are inadequately accounted for in hydrological models. In the present study, a geophysical survey using ground penetrating radar of a 0.5 ha hillslope in central New York, USA has shown that spatial variability of the continuity and depth of fragipan soils is more influential on subsurface flow pathways than the physical characteristics of the fragipan itself. The geophysical survey revealed that the depth to fragipan varied between 0.3 and 0.8 m, resulting in water table and subsurface flow dynamics similar to the ‘fill and spill hypothesis'. The survey also indicated that the fragipan is interrupted by a higher conductive glacial sand lens that facilitates percolation of subsurface flow beneath the fragipan. The effect of the spatial variability of fragipan soils on subsurface flow pathways and flux was examined in further detail by installation of a 1.5 m wide, 1.5 m deep and 12.5 m long trench at the base of the 125 m long hillslope. The trench was installed in a variable source area (VSA) that forms at the base of the hillslope. The trench was instrumented with a surface flow collector measuring runoff from the upper 5 cm of the soil, and two collector drains installed at the soil-fragipan interface in 0.4 m depth and at the base of the trench (1.5 m depth). In addition, water levels were recorded at 5-min intervals in a 10 m x 10 m grid at the upslope contributing area of the trench. Soils in the study site are

  9. Removal of nutrients from septic tank effluent with baffle subsurface-flow constructed wetlands.

    PubMed

    Cui, Lihua; Ouyang, Ying; Yang, Weizhi; Huang, Zhujian; Xu, Qiaoling; Yu, Guangwei

    2015-04-15

    Three new baffle flow constructed wetlands (CWs), namely the baffle horizontal flow CW (Z1), baffle vertical flow CW (Z2) and baffle hybrid flow CW (Z3), along with one traditional horizontal subsurface flow CW (Z4) were designed to test the removal efficiency of nitrogen (N) and phosphorus (P) from the septic tank effluent under varying hydraulic retention times (HRTs). Results showed that the optimal HRT was two days for maximal removal of N and P from the septic tank effluent among the four CWs. At this HRT, the Z1, Z2, Z3 and Z4 CWs removed, respectively, 49.93, 58.50, 46.01 and 44.44% of TN as well as 87.82, 93.23, 95.97 and 91.30% of TP. Our study further revealed that the Z3 CW was the best design for overall removal of N and P from the septic tank effluent due to its hybrid flow directions with better oxygen supply inside the CW system.

  10. Recovery of bypassed oil in the Dundee Formation using horizontal drains. Quarterly report, October 1 - December 31, 1996

    SciTech Connect

    Wood, J.R.

    1997-01-01

    The principal objective of this project is to demonstrate the feasibility and economic success of producing oil from abandoned or nearly abandoned fields in the Dundee Formation of Central Michigan using horizontal drilling technology. A site for a horizontal well was selected in Crystal Field, a nearly-abandoned Dundee oil field in Michigan. This field had produced over 8 million barrels of oil, mostly in the 1930`s and 1940`s. At the height of development, Crystal Field produced from 193 wells, but by 1995, only seven producing wells remained, each producing less than 10 bbls/day. A horizontal well was drilled as a field demonstration pilot, funded through this DOE project, and was successful. It has produced over 37,000 bbls of oil as of December 31, 1996 at sustained rate of {approximately}100 bbls/day. At a nominal wellhead price of $20/bbl, this well has made about $750,000 and is still going strong. Two additional horizontal wells have just been completed and are on test. Core and logs from the Dundee interval were recovered from a vertical borehole at the same surface location. The horizontal well was brought on production at a rate of 100 bbls/day and is probably capable of producing at a higher rate. The addition of several horizontal wells, similar to the demonstration well, will likely add another 2 million bbls (or more) to the cumulative production of the field over the next few years. The presence of untapped oil in this Dundee field was dramatically demonstrated and the favorable economics were made clearly evident. If other abandoned Dundee fields are re-developed in a similar manner, the additional oil produced could exceed 80 million barrels. Horizontal drilling will likely revolutionize the development of old carbonate fields such as those in the Dundee of Michigan.

  11. Soviet pilot-physician program.

    PubMed

    Vlassov, V; Ushakov, I

    1999-07-01

    The program for training pilot-physicians was started in 1952. It was the first and the only one in the history of the USSR/Russia. Young military physicians from different military forces and graduates of the Saratov Military Medical Faculty were invited to participate in the program. Selected military physicians were sent for 2 yr of flight training. Six graduates from Omsk School became bomber pilots, while eight graduates from Chuguev School were appointed instructor pilots. Special positions and regulations for pilot-physicians were not created. Some pilot-physicians continued their aviation career, and some returned to medicine. For a short time a limited number of pilot-physician positions existed in the research institute in Moscow. Two graduates from this program were appointed to these positions. One of the pilot-physicians became a cosmonaut; and at least six obtained scientific degrees in medicine and made significant contributions to the development of aerospace medicine.

  12. Performance of a pilot showcase of different wetland systems in an urban setting in Singapore.

    PubMed

    Quek, B S; He, Q H; Sim, C H

    2015-01-01

    The Alexandra Wetlands, part of PUB's Active, Beautiful, Clean Waters (ABC Waters) Programme, showcase a surface flow wetland, an aquatic pond and a sub-surface flow wetland on a 200 m deck built over an urban drainage canal. Water from the canal is pumped to a sedimentation basin, before flowing in parallel to the three wetlands. Water quality monitoring was carried out monthly from April 2011 to December 2012. The order of removal efficiency is sub-surface flow (81.3%) >aquatic pond (58.5%) >surface flow (50.7%) for total suspended solids (TSS); sub-surface (44.9%) >surface flow (31.9%) >aquatic pond (22.0%) for total nitrogen (TN); and surface flow (56.7%) >aquatic pond (39.8%) >sub-surface flow (5.4%) for total phosphorus (TP). All three wetlands achieved the Singapore stormwater treatment objectives (STO) for TP removal, but only the sub-surface flow wetland met the STO for TSS, and none met the STO for TN. Challenges in achieving satisfactory performance include inconsistent feed water quality, undesirable behaviour such as fishing, release of pets and feeding of animals in the wetlands, and canal dredging during part of the monitoring period. As a pilot showcase, the Alexandra Wetlands provide useful lessons for implementing multi-objective wetlands in an urban setting.

  13. Piloted simulation study of an ILS approach of a twin-pusher business/commuter turboprop aircraft configuration

    NASA Technical Reports Server (NTRS)

    Riley, Donald R.; Brandon, Jay M.; Glaab, Louis J.

    1994-01-01

    A six-degree-of-freedom nonlinear simulation of a twin-pusher, turboprop business/commuter aircraft configuration representative of the Cessna ATPTB (Advanced turboprop test bed) was developed for use in piloted studies with the Langley General Aviation Simulator. The math models developed are provided, simulation predictions are compared with with Cessna flight-test data for validation purposes, and results of a handling quality study during simulated ILS (instrument landing system) approaches and missed approaches are presented. Simulated flight trajectories, task performance measures, and pilot evaluations are presented for the ILS approach and missed-approach tasks conducted with the vehicle in the presence of moderate turbulence, varying horizontal winds and engine-out conditions. Six test subjects consisting of two research pilots, a Cessna test pilot, and three general aviation pilots participated in the study. This effort was undertaken in cooperation with the Cessna Aircraft Company.

  14. RADIOIODINE GEOCHEMISTRY IN THE SRS SUBSURFACE ENVIRONMENT

    SciTech Connect

    Kaplan, D.; Emerson, H.; Powell, B.; Roberts, K.; Zhang, S.; Xu, C.; Schwer, K.; Li, H.; Ho, Y.; Denham, M.; Yeager, C.; Santschi, P.

    2013-05-16

    Iodine-129 is one of the key risk drivers for several Savannah River Site (SRS) performance assessments (PA), including that for the Low-Level Waste Disposal Facility in E-Area. In an effort to reduce the uncertainty associated with the conceptual model and the input values used in PA, several studies have recently been conducted dealing with radioiodine geochemistry at the SRS. The objective of this report was to review these recent studies and evaluate their implications on SRS PA calculations. For the first time, these studies measured iodine speciation in SRS groundwater and provided technical justification for assuming the presence of more strongly sorbing species (iodate and organo-iodine), and measured greater iodine sediment sorption when experiments included these newly identified species; specifically they measured greater sorption coefficients (K{sub d} values: the concentration ratio of iodine on the solid phase divided by the concentration in the aqueous phase). Based on these recent studies, new best estimates were proposed for future PA calculations. The new K{sub d} values are greater than previous recommended values. These proposed K{sub d} values reflect a better understanding of iodine geochemistry in the SRS subsurface environment, which permits reducing the associated conservatism included in the original estimates to account for uncertainty. Among the key contributing discoveries supporting the contention that the K{sub d} values should be increased are that: 1) not only iodide (I{sup -}), but also the more strongly sorbing iodate (IO{sub 3}{sup -}) species exists in SRS groundwater (average total iodine = 15% iodide, 42% iodate, and 43% organoiodine), 2) when iodine was added as iodate, the measured K{sub d} values were 2 to 6 times greater than when the iodine was added as iodide, and perhaps most importantly, 3) higher desorption (10 to 20 mL/g) than (ad)sorption (all previous studies) K{sub d} values were measured. The implications of this

  15. High accuracy diffuse horizontal irradiance measurements without a shadowband

    SciTech Connect

    Schlemmer, J.A; Michalsky, J.J.

    1995-12-31

    The standard method for measuring diffuse horizontal irradiance uses a fixed shadowband to block direct solar radiation. This method requires a correction for the excess skylight blocked by the band, and this correction varies with sky conditions. Alternately, diffuse horizontal irradiance may be calculated from total horizontal and direct normal irradiance. This method is in error because of angular (cosine) response of the total horizontal pyranometer to direct beam irradiance. This paper describes an improved calculation of diffuse horizontal irradiance from total horizontal and direct normal irradiance using a predetermination of the angular response of the total horizontal pyranometer. We compare these diffuse horizontal irradiance calculations with measurements made with a shading-disk pyranometer that shields direct irradiance using a tracking disk. Results indicate significant improvement in most cases. Remaining disagreement most likely arises from undetected tracking errors and instrument leveling.

  16. 12. VIEW LOOKING SOUTHWEST, CHESTNUT ST. (lower horizontal line) TO ...

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

    12. VIEW LOOKING SOUTHWEST, CHESTNUT ST. (lower horizontal line) TO WALNUT ST. (upper horizontal line), SHOWING SECOND BANK OF U.S. - Independence National Historical Park, Walnut, Sixth, Chestnut & Second Streets, Philadelphia, Philadelphia County, PA

  17. Modeling Gas Transport in the Shallow Subsurface During the ZERT CO2 Release Test

    SciTech Connect

    Oldenburg, Curtis M.; Lewicki, Jennifer L.; Dobeck, Laura; Spangler, Lee

    2009-01-15

    We used the multiphase and multicomponent TOUGH2/EOS7CA model to carry out predictive simulations of CO{sub 2} injection into the shallow subsurface of an agricultural field in Bozeman, Montana. The purpose of the simulations was to inform the choice of CO{sub 2} injection rate and design of monitoring and detection activities for a CO{sub 2} release experiment. The release experiment configuration consists of a long horizontal well (70 m) installed at a depth of approximately 2.5 m into which CO{sub 2} is injected to mimic leakage from a geologic carbon sequestration site through a linear feature such as a fault. We estimated the permeability of the soil and cobble layers present at the site by manual inversion of measurements of soil CO{sub 2} flux from a vertical-well CO{sub 2} release. Based on these estimated permeability values, predictive simulations for the horizontal well showed that CO{sub 2} injection just below the water table creates an effective gas-flow pathway through the saturated zone up to the unsaturated zone. Once in the unsaturated zone, CO{sub 2} spreads out laterally within the cobble layer, where liquid saturation is relatively low. CO{sub 2} also migrates upward into the soil layer through the capillary barrier and seeps out at the ground surface. The simulations predicted a breakthrough time of approximately two days for the 100kg d{sup -1} injection rate, which also produced a flux within the range desired for testing detection and monitoring approaches. The seepage area produced by the model was approximately five meters wide above the horizontal well, compatible with the detection and monitoring methods tested. For a given flow rate, gas-phase diffusion of CO{sub 2} tends to dominate over advection near the ground surface, where the CO{sub 2} concentration gradient is large, while advection dominates deeper in the system.

  18. Modelling subsurface hydrology in Mediterranean regions to investigate spatial and temporal trends

    NASA Astrophysics Data System (ADS)

    Evans, Cristina M.; Singer, Michael B.; Dritschel, David G.

    2016-04-01

    Mediterranean environments have highly variable hydrologic regimes characterised by two distinct seasons: cold/wet and warm/dry. Understanding how this climate is expressed in subsurface hydrology is a basis for the effective management of water as a resource. Riparian systems are particularly complex due to the contribution of both infiltrating precipitation and subsurface hyporheic flows. Therefore a more in-depth investigation of subsurface hydrology is required to understand riparian corridors. Numerical models can be used to simulate soil-water distribution and exchange. We have built-on existing theory of flow through porous media to create a physically-based, river- and climate-driven numerical model of hyporheic flow and infiltration/evaporation that predicts the water content at any depth in a soil column and at any distance from the river channel. The model incorporates the Richards equation - describing the vertical infiltration and diffusion of water in porous media - and the Boussinesq equation, which simulates the horizontal evolution of the water-table (hyporheic flow). These equations have been fully coupled to reflect the interplay between the saturated and unsaturated zones. The model produces a daily time-series of water table elevations and vertical soil moisture patterns in the vadose zones to allow us to study the hydrological partitioning and soil-moisture distribution in a given soil profile. We apply this tool to Mediterranean regions over a number of years to explore seasonal and inter-annual hydrological patterns. Two sites along the Rhône River in France with distinct climates allow us to investigate the impact of riverine and climate functioning. In particular we assess the impact of distance from the river channel and exposure to warmer and dryer conditions. Finally, the temporal legacy of extreme events such as floods and droughts is considered within the context of the impact to riparian vegetation. These comparisons will resolve

  19. Biogenic Carbon on Mars: A Subsurface Chauvinistic Viewpoint

    NASA Astrophysics Data System (ADS)

    Onstott, T. C.; Lau, C. Y. M.; Magnabosco, C.; Harris, R.; Chen, Y.; Slater, G.; Sherwood Lollar, B.; Kieft, T. L.; van Heerden, E.; Borgonie, G.; Dong, H.

    2015-12-01

    A review of 150 publications on the subsurface microbiology of the continental subsurface provides ~1,400 measurements of cellular abundances down to 4,800 meter depth. These data suggest that the continental subsurface biomass is comprised of ~1016-17 grams of carbon, which is higher than the most recent estimates of ~1015 grams of carbon (1 Gt) for the marine deep biosphere. If life developed early in Martian history and Mars sustained an active hydrological cycle during its first 500 million years, then is it possible that Mars could have developed a subsurface biomass of comparable size to that of Earth? Such a biomass would comprise a much larger fraction of the total known Martian carbon budget than does the subsurface biomass on Earth. More importantly could a remnant of this subsurface biosphere survive to the present day? To determine how sustainable subsurface life could be in isolation from the surface we have been studying subsurface fracture fluids from the Precambrian Shields in South Africa and Canada. In these environments the energetically efficient and deeply rooted acetyl-CoA pathway for carbon fixation plays a central role for chemolithoautotrophic primary producers that form the base of the biomass pyramid. These primary producers appear to be sustained indefinitely by H2 generated through serpentinization and radiolytic reactions. Carbon isotope data suggest that in some subsurface locations a much larger population of secondary consumers are sustained by the primary production of biogenic CH4 from a much smaller population of methanogens. These inverted biomass and energy pyramids sustained by the cycling of CH4 could have been and could still be active on Mars. The C and H isotopic signatures of Martian CH4 remain key tools in identifying potential signatures of an extant Martian biosphere. Based upon our results to date cavity ring-down spectroscopic technologies provide an option for making these measurements on future rover missions.

  20. Study of the Local Horizon. (Spanish Title: Estudio del Horizonte Local.) Estudo do Horizonte Local

    NASA Astrophysics Data System (ADS)

    Ros, Rosa M.

    2009-12-01

    The study of the horizon is fundamental to easy the first observations of the students at any education center. A simple model, to be developed in each center, allows to easy the study and comprehension of the rudiments of astronomy. The constructed model is presented in turn as a simple equatorial clock, other models (horizontal and vertical) may be constructed starting from it. El estudio del horizonte es fundamental para poder facilitar las primeras observaciones de los alumnos en un centro educativo. Un simple modelo, que debe realizarse para cada centro, nos permite facilitar el estudio y la comprensión de los primeros rudimentos astronómicos. El modelo construido se presenta a su vez como un sencillo modelo de reloj ecuatorial y a partir de él se pueden construir otros modelos (horizontal y vertical). O estudo do horizonte é fundamental para facilitar as primeiras observações dos alunos num centro educativo. Um modelo simples, que deve ser feito para cada centro, permite facilitar o estudo e a compreensão dos primeiros rudimentos astronômicos. O modelo construído apresenta-se, por sua vez, como um modelo simples de relógio equatorial e a partir dele pode-se construir outros modelos (horizontal e vertical)

  1. Sidewall containment of liquid metal with horizontal alternating magnetic fields

    DOEpatents

    Praeg, W.F.

    1995-01-31

    An apparatus is disclosed for confining molten metal with a horizontal alternating magnetic field. In particular, this invention employs a magnet that can produce a horizontal alternating magnetic field to confine a molten metal at the edges of parallel horizontal rollers as a solid metal sheet is cast by counter-rotation of the rollers. 19 figs.

  2. Horizontal core acquisition and orientation for formation evaluation

    SciTech Connect

    Skopec, R.A. ); Mann, M.M. ); Grier, S.P. )

    1992-03-01

    The increase in horizontal drilling activity has produced a need for improved coring technology. The development of a reliable horizontal (medium-radius) coring and orientation system has greatly improved the acquisition of information necessary for formation evaluation and reservoir engineering. This paper describes newly developed hardware and methods for obtaining horizontal core sections.

  3. [Extraction of 56 horizontally impacted teeth using dental implanter].

    PubMed

    Zhang, Yan-ping; Liang, Na

    2005-06-01

    50 cases, totally 56 horizontally impacted teeth were extracted using dental implanter to remove the alveolar bone. Another 56 horizontally impacted teeth were extracted using high speed turbine.It's concluded that is a safe and easy way using the dental implanter to remove the horizontally impacted teeth, and the reaction and the complications could be minimized.

  4. Evaluation of Subsurface Flow and Free-water Surface Wetlands Treating NPR-3 Produced Water - Year No. 1

    SciTech Connect

    Myers, J. E.; Jackson, L. M.

    2001-10-13

    This paper is a summary of some of the activities conducted during the first year of a three-year cooperative research and development agreement (CRADA) between the Department of Energy (DOE) Rocky Mountain Oilfield Testing Center (RMOTC) and Texaco relating to the treatment of produced water by constructed wetlands. The first year of the CRADA is for design, construction and acclimation of the wetland pilot units. The second and third years of the CRADA are for tracking performance of pilot wetlands as the plant and microbial communities mature. A treatment wetland is a proven technology for the secondary and tertiary treatment of produced water, storm water and other wastewaters. Treatment wetlands are typically classified as either free-water surface (FWS) or subsurface flow (SSF). Both FWS and SSF wetlands work well when properly designed and operated. This paper presents a collection of kinetic data gathered from pilot units fed a slipstream of Wyoming (NPR-3) produced water. The pilot units are set up outdoors to test climatic influences on treatment. Monitoring parameters include evapotranspiration, plant growth, temperature, and NPDES discharge limits. The pilot wetlands (FWS and SSF) consist of a series of 100-gal plastic tubs filled with local soils, gravel, sharp sand and native wetland plants (cattail (Typha spp.), bulrush (Scirpus spp.), dwarf spikerush (Eleocharis)). Feed pumps control hydraulic retention time (HRT) and simple water control structures control the depth of water. The treated water is returned to the existing produced water treatment system. All NPDES discharge limits are met. Observations are included on training RMOTC summer students to do environmental work.

  5. Scanning Tunneling Microscopy methods for spectroscopic imaging of subsurface interfaces

    NASA Technical Reports Server (NTRS)

    Bell, L. D.; Kaiser, W. J.

    1988-01-01

    A new method for spatially-resolved, spectroscopic investigation of subsurface interface structure has been developed. The method, Ballistic Electron Emission Microscopy (BEEM), is based on Scanning Tunneling Microscopy (STM) techniques. BEEM combines STM vacuum tunneling with unique ballistic electron spectroscopy capabilities. BEEM enables, for the first time, direct imaging of subsurface interface electronic properties with nanometer spatial resolution. STM topographic images of surface structure and BEEM images of subsurface properties are obtained simultaneously. BEEM capabilities are demonstrated by investigation of important metal-semiconductor interfaces.

  6. Enhanced bioremediation of subsurface contamination: Enzyme recruitment and redesign

    SciTech Connect

    Brockman, F.J.; Ornstein, R.L.

    1991-12-01

    Subsurface systems containing radionuclide, heavy metal, and organic wastes must be carefully attended to avoid further impacts to the environment or exposures to human populations. It is appropriate, therefore, to invest in basic research to develop the requisite tools and methods for addressing complex cleanup problems. The rational modification of subsurface microoganisms by enzyme recruitment and enzyme design, in concert with engineered systems for delivery of microorganisms and nutrients to the contaminated zone, are potentially useful tools in the spectrum of approaches that will be required for successful remediation of deep subsurface contamination.

  7. The DOE Subsurface Microbial Culture Collection (SMCC)

    SciTech Connect

    Balkwill, David L.

    2006-05-23

    The primary activities associated with maintenance of the Subsurface Microbial Culture Collection (SMCC) were designed to ensure that the collection served as a valuable resource to DOE-funded and other scientists, especially DOE-funded scientists associated with the NABIR Program. These activities were carried out throughout the period covered by this report and in-cluded: (1) assistance in the selection of cultures for research, (2) distribution of cultures and/or data on request, (3) incorporation of newly isolated microbial strains, (4) preservation of newly isolated strains, (5) partial characterization of newly isolated strains, (6) development and main-tenance of representative subsets of cultures, (6) screening of SMCC strains for specific charac-teristics, (7) phylogenetic characterization of SMCC strains, (8) development and maintenance of a SMCC website, (9) maintenance of the SMCC databases, (10) archiving of SMCC records, and (11) quality assurance/quality control (QA/QC) activities. We describe in the Final Technical Report our accomplishments related to these activities during the period covered by this report.

  8. Evidence for a subsurface ocean on Europa

    USGS Publications Warehouse

    Carr, M.H.; Belton, M.J.S.; Chapman, C.R.; Davies, M.E.; Geissler, P.; Greenberg, R.; McEwen, A.S.; Tufts, B.R.; Greeley, R.; Sullivan, R.; Head, J.W.; Pappalardo, R.T.; Klaasen, K.P.; Johnson, T.V.; Kaufman, J.; Senske, D.; Moore, J.; Neukum, G.; Schubert, G.; Burns, J.A.; Thomas, P.; Veverka, J.

    1998-01-01

    Ground-based spectroscopy of Jupiter's moon Europa, combined with gravity data, suggests that the satellite has an icy crust roughly 150 km thick and a rocky interior. In addition, images obtained by the Voyager spacecraft revealed that Europa's surface is crossed by numerous intersecting ridges and dark bands (called lineae) and is sparsely cratered, indicating that the terrain is probably significantly younger than that of Ganymede and Callisto. It has been suggested that Europa's thin outer ice shell might be separated from the moon's silicate interior by a liquid water layer, delayed or prevented from freezing by tidal heating; in this model, the lineae could be explained by repetitive tidal deformation of the outer ice shell. However, observational confirmation of a subsurface ocean was largely frustrated by the low resolution (>2 km per pixel) of the Voyager images. Here we present high-resolution (54 m per pixel) Galileo spacecraft images of Europa, in which we find evidence for mobile 'icebergs'. The detailed morphology of the terrain strongly supports the presence of liquid water at shallow depths below the surface, either today or at some time in the past. Moreover, lower- resolution observations of much larger regions suggest that the phenomena reported here are widespread.

  9. Evidence for a subsurface ocean on Europa.

    PubMed

    Carr, M H; Belton, M J; Chapman, C R; Davies, M E; Geissler, P; Greenberg, R; McEwen, A S; Tufts, B R; Greeley, R; Sullivan, R; Head, J W; Pappalardo, R T; Klaasen, K P; Johnson, T V; Kaufman, J; Senske, D; Moore, J; Neukum, G; Schubert, G; Burns, J A; Thomas, P; Veverka, J

    1998-01-22

    Ground-based spectroscopy of Jupiter's moon Europa, combined with gravity data, suggests that the satellite has an icy crust roughly 150 km thick and a rocky interior. In addition, images obtained by the Voyager spacecraft revealed that Europa's surface is crossed by numerous intersecting ridges and dark bands (called lineae) and is sparsely cratered, indicating that the terrain is probably significantly younger than that of Ganymede and Callisto. It has been suggested that Europa's thin outer ice shell might be separated from the moon's silicate interior by a liquid water layer, delayed or prevented from freezing by tidal heating; in this model, the lineae could be explained by repetitive tidal deformation of the outer ice shell. However, observational confirmation of a subsurface ocean was largely frustrated by the low resolution (>2 km per pixel) of the Voyager images. Here we present high-resolution (54 m per pixel) Galileo spacecraft images of Europa, in which we find evidence for mobile 'icebergs'. The detailed morphology of the terrain strongly supports the presence of liquid water at shallow depths below the surface, either today or at some time in the past. Moreover, lower-resolution observations of much larger regions suggest that the phenomena reported here are widespread.

  10. Delineating groundwater and subsurface structures by

    NASA Astrophysics Data System (ADS)

    Araffa, Sultan Awad Sultan; Helaly, Ahmed S.; Khozium, Ashraf; Lala, Amir M. S.; Soliman, Shokry A.; Hassan, Noha M.

    2015-06-01

    Geophysical tools such as magnetic, gravity and electric resistivity have been used to delineate subsurface structures, groundwater aquifer around Cairo-Belbies Desert road. A dipole-dipole section was measured at the central part of the study area with 2100 m length and electrode spacing 50 m for greater penetration depth. The results of the inverse resistivity data indicate that the study area includes two groundwater aquifers at different depths. The shallow aquifer water is near the surface and the deep aquifer lies at depth of about 115 m and exhibits low resistivity values ranging from 20 to 100 ohm m. One hundred and fifty-two gravity stations were measured using Autograv gravimeter (CG3), different gravity corrections (drift, elevation and latitude corrections) were applied. The corrected data represented by Bouguer anomaly map were filtered into regional and residual gravity anomaly maps. The residual gravity map indicates that the area is dissected by many faults with NW-SE, N-S, E-W and NE-SW trends. One hundred and fifty-three ground magnetic measurements are collected using two Proton magnetometers (Envimag). The corrected magnetic data are represented by total magnetic intensity map that was reduced to the magnetic pole. 3D magnetic modeling was applied to detect the depth of basaltic sheet and basement complex. The results indicated that the elevation of upper surface of basalt is ranging from 148 to -153 m and the elevation of lower surface of basalt is ranging from 148 to 269 m.

  11. Subsurface Transport Over Multiple Phases Demonstration Software

    SciTech Connect

    2016-01-05

    The STOMP simulator is a suite of numerical simulators developed by Pacific Northwest National Laboratory for addressing problems involving coupled multifluid hydrologic, thermal, geochemical, and geomechanical processes in the subsurface. The simulator has been applied to problems concerning environmental remediation, environmental stewardship, carbon sequestration, conventional petroleum production, and the production of unconventional hydrocarbon fuels. The simulator is copyrighted by Battelle Memorial Institute, and is available outside of PNNL via use agreements. To promote the open exchange of scientific ideas the simulator is provided as source code. A demonstration version of the simulator has been developed, which will provide potential new users with an executable (not source code) implementation of the software royalty free. Demonstration versions will be offered via the STOMP website for all currently available operational modes of the simulator. The demonstration versions of the simulator will be configured with the direct banded linear system solver and have a limit of 1,000 active grid cells. This will provide potential new users with an opportunity to apply the code to simple problems, including many of the STOMP short course problems, without having to pay a license fee. Users will be required to register on the STOMP website prior to receiving an executable.

  12. Dissipation of anomalous pressures in the subsurface

    NASA Astrophysics Data System (ADS)

    Muggeridge, Ann; Abacioglu, Yafes; England, William; Smalley, Craig

    2004-11-01

    Zones of anomalous pressure, higher and lower than hydrostatic pressure, have been observed in many sedimentary basins around the world. These normally consist of groups of pressure compartments: volumes of higher-permeability rock surrounded on all sides by lower-permeability barriers. Knowledge of the timescales over which these abnormal pressures are maintained and the mechanisms by which they dissipate is critical for understanding how fluids, such as oil and gas, move in the subsurface. Existing analytic solutions investigate pressure dissipation through low-permeability barriers on top of or underneath an isolated pressure compartment. There are no analytic solutions describing pressure dissipation through lateral barriers, such as faults, or investigating the impact of groups of pressure compartments on the rate of pressure dissipation. This paper presents simple analytic models to investigate pressure dissipation through barriers, such as faults, forming the sides of pressure compartments. The timescales are compared with a solution for pressure dissipation through barriers on top of and underneath the compartment. It also investigates analytically the rate of pressure dissipation from groups of pressure compartments. Lateral seal permeabilities of 10-19 m2 may delay pressure equilibration for millions of years provided the compartment has a sufficiently high fluid storage capacity. Factors contributing toward a high fluid storage capacity include a high fluid compressibility (as is the case in hydrocarbon reservoirs) and a high porosity. The grouping of abnormally pressured compartments into "megacompartment complexes" may delay pressure dissipation for hundreds of millions of years.

  13. Phononic subsurface: Flow stabilization by crystals

    NASA Astrophysics Data System (ADS)

    Hussein, Mahmoud I.; Biringen, Sedat; Bilal, Osama R.; Kucala, Alec

    2015-11-01

    Flow control is a century-old problem where the goal is to alter a flow's natural state to achieve improved performance, such as delay of laminar-to-turbulent transition or reduction of drag in a fully developed turbulent flow. Meeting this goal promises to significantly reduce the dependence on fossil fuels for global transport. In this work, we show that phonon motion underneath a surface interacting with a flow may be tuned to cause the flow to stabilize, or destabilize, as desired. This concept is demonstrated by simulating a fully developed plane Poiseuille (channel) flow whereby a small portion of an otherwise rigid wall is replaced with a one-dimensional phononic crystal. A Tollmien-Schlichting (TS) wave is introduced to the flow as an evolving disturbance. Upon tuning the frequency-dependent phase and amplitude relations of the surface of the phononic crystal that interfaces with the flow, the TS wave is shown to stabilize, or destabilize, as needed. A theory of subsurface phonons is presented that provides an accurate prediction of this behavior without the need for a flow simulation. This represents an unprecedented capability to passively synchronize wave propagation across a fluid-structure interface and achieve favorable, and predictable, alterations to the flow properties. National Science Foundation, Grant No. 1131802.

  14. Monitoring of subsurface injection of wastes, Florida

    USGS Publications Warehouse

    Vecchioli, John

    1979-01-01

    Injection of waste liquids into Florida's subsurface is physically feasible in many places but should be accompanied by monitoring of the waste-receiving aquifer system in addition to the injection facility. Monitoring of the interaction of factors including hydrogeologic conditions, well construction, waste volumes and characteristics, and potable-water sources is desirable to assure that fresh-water resources are not being adversely affected. An effective aquifer-system monitoring program includes on-site wells located close to an injection well and open to the next-higher permeable stratum, satellite wells located hundreds to several thousands of feet from an injection well and open to the receiving aquifer, and regional wells located miles from individual injection wells and open to the receiving aquifer. An extensive aquifer-system monitoring program associated with two waste-injection facilities near Pensacola, Florida, has provided data which have aided hydrologists to understand the aquifer system's response to the injection and, accordingly, to evaluate the potential for affecting the area's fresh-water resources.

  15. Convective mixing in formations with horizontal barriers

    NASA Astrophysics Data System (ADS)

    Elenius, Maria T.; Gasda, Sarah E.

    2013-12-01

    It has been shown that convective mixing in porous media flow is important for applications such as saltwater intrusion and geological storage of carbon dioxide. In the latter case, dissolution from the injected phase to the resident brine is assisted by convective mixing, which leads to enhanced storage security through reduced buoyancy. Here, we focus on the effect of horizontal barriers on the efficiency of convective mixing. Previous investigations of the effect of heterogeneity on mixing efficiency have focused on random permeability fields or barriers of small extent compared to the intrinsic finger wavelength. The effect of horizontal barriers of larger extent, such as mudstone inclusions or thin shale deposits, has not been given sufficient attention. We perform detailed numerical investigations to represent the continuous solution of this problem in semi-infinite domains with barriers arranged in a periodic manner. The results show that mass flux into the domain, which is a measure of the efficiency of redistribution of the solute, is inversely proportional to the barrier length and proportional to the horizontal and vertical aperture between the barriers, for the cases studied. The flow structure is complex, and it depends not only on the total area of barriers but also largely on the distribution of barriers. Therefore, neither simple analytical models nor simple upscaling methods that lack information about the flow paths, can be used to predict the behavior. However, we compute the effective vertical permeability by flow-based upscaling and show that it can be used to directly obtain a first-order approximation to the mass flux into the domain.

  16. Horizontal axis Levitron—a physics demonstration

    NASA Astrophysics Data System (ADS)

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the ‘spignet’. Precession is fundamental to nuclear magnetic resonance, magnetic resonance imaging, particle traps and the movement of bodies in space. Longitudinal and lateral bounce behaviour is explained via ‘the principle of gentle superposition’ of two traps: the micro-precessional and the macro-trap. Theory is initiated. Scaling experiments are mentioned. Industrial applications might follow. Patent pending.

  17. Fluidization of a horizontally driven granular monolayer.

    PubMed

    Heckel, Michael; Sack, Achim; Kollmer, Jonathan E; Pöschel, Thorsten

    2015-06-01

    We consider the transition of a horizontally vibrated monodisperse granular monolayer between its condensed state and its three-dimensional gaseous state as a function of the vibration parameters, amplitude, and frequency as well as particle number density. The transition is characterized by an abrupt change of the dynamical state which leaves its fingerprints in several measurable quantities including dissipation rate, sound emission, and a gap size which characterizes the sloshing motion of the material. The transition and its pronounced hysteresis is explained through the energy due to the collective motion of the particles relative to the container.

  18. Does horizontal transmission invalidate cultural phylogenies?

    PubMed Central

    Greenhill, Simon J.; Currie, Thomas E.; Gray, Russell D.

    2009-01-01

    Phylogenetic methods have recently been applied to studies of cultural evolution. However, it has been claimed that the large amount of horizontal transmission that sometimes occurs between cultural groups invalidates the use of these methods. Here, we use a natural model of linguistic evolution to simulate borrowing between languages. The results show that tree topologies constructed with Bayesian phylogenetic methods are robust to realistic levels of borrowing. Inferences about divergence dates are slightly less robust and show a tendency to underestimate dates. Our results demonstrate that realistic levels of reticulation between cultures do not invalidate a phylogenetic approach to cultural and linguistic evolution. PMID:19324763

  19. From surface to subsurface and back again: the contribution of subsurface particle motion to surface armoring

    NASA Astrophysics Data System (ADS)

    Ferdowsi, B.; Jerolmack, D. J.; Ortiz, C. P.; Houssais, M.

    2015-12-01

    Armoring is the development of a coarse surface layer of sediments on a river bed, which overlies a smaller and typically more heterogeneous substrate. All existing models for this phenomenon are predicated on the idea that armoring develops due to size-selective transport and kinetic sieving at the surface of the granular bed. Here examine the development of armoring in the absence of size-selective surface transport, and demonstrate that subsurface particle movement can create an armored surface layer. We first conduct experiments in a laminar and annular flume, over a range of Shields stresses, with bimodal and refractive index-matched spherical sediments; this allows us to image the internal motion of the granular bed that is sheared from above by a viscous oil. Fluid-driven particle motion of the surface layer results in granular shear, that drives motion deep into the bed. This subsurface motion causes an upward migration of coarser particles, at a rate that is proportional to the granular shear rate. Comparison of experimental results to an existing continuum-granular flow model suggest that armoring in our bed-load exeriments is entirely consistent with shear-induced segregation in dry avalanches - but is slower. There is no size-selective transport at the surface in the experiments, as the annular flume is mass conserving and all particles move as bed load; this was confirmed by observation. To probe the granular physics of armor development further, we perform numerical simulations using a discrete element model (DEM) of granular flow, with and without damping. Simulations reproduce salient features of the experiments, and indicate that armoring is robust but that the rate of segregation is related to the degree of viscous damping. We posit that subsurface granular flow is an important and perhaps dominant contributor to surface armoring in rivers. More generally, this work shows how information is transferred from the surface to the subsurface and back

  20. Medical certification of pilots.

    PubMed

    Dodds, R L

    1978-03-01

    This paper reviews some of the problems encountered in administering satisfactory medical requirements for professional pilots. The role of these requirements in the context of flight safety is discussed. The control of risk by the imposition of strict requirements is contrasted with that achieved by training designed to contain the risk introduced by incapacitation. The fact that aviation safety is based on acceptable risk levels is pointed out and the role of physician in this regard is discussed. The need for a widely accepted minimum level of fitness required for aviation duties is brought out. Certain operational aspects are touched upon. Medical requirements based on the desire to avoid on-duty incapacitation are contrasted with those designed to ensure adequate performance. The present ICAO cardiovascular requirement is discussed with particular reference to permanent grounding following myocardial infarction. The significance of inflight crew incapacitation training is pointed out and a plea for close cooperation between licensing authorities, airline operators, and pilots is made.

  1. Blind Pilot Decontamination

    NASA Astrophysics Data System (ADS)

    Muller, Ralf R.; Cottatellucci, Laura; Vehkapera, Mikko

    2014-10-01

    A subspace projection to improve channel estimation in massive multi-antenna systems is proposed and analyzed. Together with power-controlled hand-off, it can mitigate the pilot contamination problem without the need for coordination among cells. The proposed method is blind in the sense that it does not require pilot data to find the appropriate subspace. It is based on the theory of large random matrices that predicts that the eigenvalue spectra of large sample covariance matrices can asymptotically decompose into disjoint bulks as the matrix size grows large. Random matrix and free probability theory are utilized to predict under which system parameters such a bulk decomposition takes place. Simulation results are provided to confirm that the proposed method outperforms conventional linear channel estimation if bulk separation occurs.

  2. Horizontal Flows in the Photosphere and Subphotosphere of Two Active Regions

    NASA Technical Reports Server (NTRS)

    Liu, Yang; Zhao, Junwei; Schuck, P. W.

    2012-01-01

    We compare horizontal flow fields in the photosphere and in the subphotosphere (a layer 0.5 megameters below the photosphere) in two solar active regions: AR11084 and AR11158. AR11084 is a mature, simple active region without significant flaring activity, and AR11158 is a multipolar, complex active region with magnetic flux emerging during the period studied. Flows in the photosphere are derived by applying the Differential Affine Velocity Estimator for Vector Magnetograms (DAVE4VM) on HMI-observed vector magnetic fields, and the subphotospheric flows are inferred by time-distance helioseismology using HMI-observed Dopplergrams. Similar flow patterns are found for both layers for AR11084: inward flows in the sunspot umbra and outward flows surrounding the sunspot. The boundary between the inward and outward flows, which is slightly different in the photosphere and the subphotosphere, is within the sunspot penumbra. The area having inward flows in the subphotosphere is larger than that in the photosphere. For AR11158, flows in these two layers show great similarities in some areas and significant differences in other areas. Both layers exhibit consistent outward flows in the areas surrounding sunspots. On the other hand, most well-documented flux-emergence-related flow features seen in the photosphere do not have counterparts in the subphotosphere. This implies that the horizontal flows caused by flux emergence do not extend deeply into the subsurface.

  3. X-15 pilots

    NASA Technical Reports Server (NTRS)

    1960-01-01

    In keeping with the joint nature of the X-15 project, its pilots came from the four different organizations that were cooperating to design, build, and fly the airplane. X-15 Pilots in Order by Dates of First Flight A. Scott Crossfield, North American Aviation-14 flights Joseph A. Walker, NASA-25 flights Robert M. White, United States Air Force (USAF)-16 flights Forrest S. Petersen, United States Navy-5 flights John B. McKay, NASA-29 flights Robert A. Rushworth, USAF-34 flights Neil A. Armstrong, NASA-7 flights Joe H. Engle, USAF-16 flights Milton O. Thompson, NASA-14 flights William J. Knight, USAF-16 flights William H. Dana, NASA -16 flights Michael J. Adams, USAF-7 flights Total number of flights-199 The X-15 had its share of emergency landings and accidents, but only two produced serious injuries or death. On Nov. 9, 1962, Jack McKay experienced an engine failure and landed at Mud Lake, Nev. The landing gear collapsed, flipping him and the aircraft on its back. Although he recovered from his injuries sufficiently to fly again, he eventually had to retire because of them. On Nov. 15, 1967, on Michael Adams seventh flight, he entered a spin from which he was able to recover but could not bring it out of an inverted dive because of a technical problem with the adaptive flight control system. He died in the resultant crash of the X-15 number three. This short video clip provides two different views of X-15 pilots. In the first group are (left to right): Bob Rushworth and Joe Engle, Jack McKay, Pete Knight, Milt Thompson, and Bill Dana. The pilots shown in the close-up views are McKay, Thompson, and Dana.

  4. The fighter pilot's egg

    NASA Astrophysics Data System (ADS)

    Fry, Dale W.

    1990-03-01

    Of common interest to fighter pilots is what maneuver should be flown to accomplish a 360° heading change in the least time. Among the infinite possibilities, analytic expressions for a very commonly used maneuver, a roughly circular planar turn that accomplishes the required heading change, are derived and examined under four realistic assumptions. Contrary to common belief, the time to complete the stated heading change turns out to be independent of the inclination of the plane of the turn.

  5. Telescience Testbed Pilot Program

    NASA Technical Reports Server (NTRS)

    Gallagher, Maria L. (Editor); Leiner, Barry M. (Editor)

    1988-01-01

    The Telescience Testbed Pilot Program (TTPP) is intended to develop initial recommendations for requirements and design approaches for the information system of the Space Station era. Multiple scientific experiments are being performed, each exploring advanced technologies and technical approaches and each emulating some aspect of Space Station era science. The aggregate results of the program will serve to guide the development of future NASA information systems.

  6. Pilot-Vehicle Interface

    DTIC Science & Technology

    2000-03-01

    facteurs humains lies au pilotage des avions de combat tres manoeuvrants] To order the complete compilation report, use: ADA388054 The component part...whether providing this sizes and distances to external objects. abundant amount of information is in the pilot’s best 6.3.1.2 HMD/T Symbology Size...more feasible under high acceleration of operator movement and external electrical activity conditions, compared to head or hand movement, on signal

  7. ADS pilot program Plan

    NASA Technical Reports Server (NTRS)

    Clauson, J.; Heuser, J.

    1981-01-01

    The Applications Data Service (ADS) is a system based on an electronic data communications network which will permit scientists to share the data stored in data bases at universities and at government and private installations. It is designed to allow users to readily locate and access high quality, timely data from multiple sources. The ADS Pilot program objectives and the current plans for accomplishing those objectives are described.

  8. Pilots 2.0: DIRAC pilots for all the skies

    NASA Astrophysics Data System (ADS)

    Stagni, F.; Tsaregorodtsev, A.; McNab, A.; Luzzi, C.

    2015-12-01

    In the last few years, new types of computing infrastructures, such as IAAS (Infrastructure as a Service) and IAAC (Infrastructure as a Client), gained popularity. New resources may come as part of pledged resources, while others are opportunistic. Most of these new infrastructures are based on virtualization techniques. Meanwhile, some concepts, such as distributed queues, lost appeal, while still supporting a vast amount of resources. Virtual Organizations are therefore facing heterogeneity of the available resources and the use of an Interware software like DIRAC to hide the diversity of underlying resources has become essential. The DIRAC WMS is based on the concept of pilot jobs that was introduced back in 2004. A pilot is what creates the possibility to run jobs on a worker node. Within DIRAC, we developed a new generation of pilot jobs, that we dubbed Pilots 2.0. Pilots 2.0 are not tied to a specific infrastructure; rather they are generic, fully configurable and extendible pilots. A Pilot 2.0 can be sent, as a script to be run, or it can be fetched from a remote location. A pilot 2.0 can run on every computing resource, e.g.: on CREAM Computing elements, on DIRAC Computing elements, on Virtual Machines as part of the contextualization script, or IAAC resources, provided that these machines are properly configured, hiding all the details of the Worker Nodes (WNs) infrastructure. Pilots 2.0 can be generated server and client side. Pilots 2.0 are the “pilots to fly in all the skies”, aiming at easy use of computing power, in whatever form it is presented. Another aim is the unification and simplification of the monitoring infrastructure for all kinds of computing resources, by using pilots as a network of distributed sensors coordinated by a central resource monitoring system. Pilots 2.0 have been developed using the command pattern. VOs using DIRAC can tune pilots 2.0 as they need, and extend or replace each and every pilot command in an easy way. In this

  9. X-15 Pilots

    NASA Technical Reports Server (NTRS)

    1966-01-01

    The X-15 flight crew, left to right: Air Force Captain Joseph H. Engle, Air Force Major Robert A. Rushworth, NASA pilot John B. 'Jack' McKay, Air Force Major William J. 'Pete' Knight, NASA pilot Milton O. Thompson, and NASA pilot Bill Dana. First flown in 1959 from the NASA High Speed Flight Station (later renamed the Dryden Flight Research Center), the rocket-powered X-15 was developed to provide data on aerodynamics, structures, flight controls and the physiological aspects of high speed, high altitude flight. Three were built by North American Aviation for NASA and the U.S. Air Force. They made a total of 199 flights during a highly successful research program lasting almost ten years. The X-15's main rocket engine provided thrust for the first 80 to 120 seconds of a 10 to 11 minute flight; the aircraft then glided to a 200 mph landing. The X-15 reached altitudes of 354,200 feet (67.08 miles) and a speed of 4,520 mph (Mach 6.7).

  10. Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species.

    PubMed

    Barbera, Antonio C; Borin, Maurizio; Cirelli, Giuseppe L; Toscano, Attilio; Maucieri, Carmelo

    2015-02-01

    This study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m(-2)) followed by C. zizanioides (5.3 kg m(-2)) and C. papyrus (1.8 kg m(-2)). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m(-2), respectively, whereas M. giganteus emitted 3,395 g m(-2). Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m(-2) and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m(-2). The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m(-2)) followed by C. zizanioides (3.78 kg m(-2)) and C. papyrus (1.89 kg m(-2)). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth.

  11. Subsurface Characterization To Support Evaluation Of Radionuclide Transport And Attenuation

    EPA Science Inventory

    Remediation of ground water contaminated with radionuclides may be achieved using attenuation-based technologies. These technologies may rely on engineered processes (e.g., bioremediation) or natural processes (e.g., monitored natural attenuation) within the subsurface. In gene...

  12. Microbial Life in the Deep Subsurface: Deep, Hot and Radioactive

    NASA Technical Reports Server (NTRS)

    DeStefano, Andrea L.; Ford, Jill C.; Winsor, Seana K.; Allen, Carlton C.; Miller, Judith; McNamara, Karen M.; Gibson, Everett K., Jr.

    2000-01-01

    Recent studies, motivated in part by the search for extraterrestrial life, continue to expand the recognized limits of Earth's biosphere. This work explored evidence for life a high-temperature, radioactive environment in the deep subsurface.

  13. SITE TECHNOLOGY CAPSULE: SUBSURFACE VOLATILIZATION AND VENTILATION SYSTEM (SVVS)

    EPA Science Inventory

    The Subsurface Volatilization and Ventilation System is an integrated technology used for attacking all phases of volatile organic compound (VOC) contamination in soil and groundwater. The SVVS technology promotes insitu remediation of soil and groundwater contaminated with or-ga...

  14. A hydrogen-based subsurface microbial community dominated by methanogens

    NASA Astrophysics Data System (ADS)

    Chapelle, Francis H.; O'Neill, Kathleen; Bradley, Paul M.; Methé, Barbara A.; Ciufo, Stacy A.; Knobel, LeRoy L.; Lovley, Derek R.

    2002-01-01

    The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16S ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.

  15. A hydrogen-based subsurface microbial community dominated by methanogens.

    PubMed

    Chapelle, Francis H; O'Neill, Kathleen; Bradley, Paul M; Methé, Barbara A; Ciufo, Stacy A; Knobel, LeRoy L; Lovley, Derek R

    2002-01-17

    The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16S ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.

  16. SUBSURFACE VOLATIZATION AND VENTILATION SYSTEM (SVVS) - INNOVATIVE TECHNOLOGY REPORT

    EPA Science Inventory

    This report summarizes the findings associated with a Demonstration Test of Environmental Improvement Technologies’ (EIT) Subsurface Volatilization and Ventilation System (SVVS) process. The technology was evaluated under the EPA Superfund Innovative Technology Evaluation (SITE) ...

  17. A hydrogen-based subsurface microbial community dominated by methanogens

    USGS Publications Warehouse

    Chapelle, F.H.; O'Neil, Kyle; Bradley, P.M.; Methe, B.A.; Ciufo, S.A.; Knobel, L.L.; Lovley, D.R.

    2002-01-01

    The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem1-5. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16s ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.

  18. User's Guide for Evaluating Subsurface Vapor Intrusion into Buildings

    EPA Pesticide Factsheets

    This revised version of the User's Guide corresponds with the release of Version 3.1 of the Johnson and Ettinger (1991) model (J E) spreadsheets for estimating subsurface vapor intrusion into buildings.

  19. SOLID OXYGEN SOURCE FOR BIOREMEDIATION IN SUBSURFACE SOILS

    EPA Science Inventory

    Sodium percarbonate was encapsulated in poly(vinylidene chloride) to determine its potential as a slow-release oxygen source for biodegradation of contaminan ts in subsurface soils. In laboratory studies under aqueous conditions, the encapsulated sodium percarbonate was estimate...

  20. 14 CFR 61.73 - Military pilots or former military pilots: Special rules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military...

  1. 14 CFR 61.73 - Military pilots or former military pilots: Special rules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military...

  2. 14 CFR 61.73 - Military pilots or former military pilots: Special rules.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military...

  3. 14 CFR 61.73 - Military pilots or former military pilots: Special rules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military...

  4. 14 CFR 61.73 - Military pilots or former military pilots: Special rules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military...

  5. Matrix stimulation method for horizontal wells

    SciTech Connect

    Economides, M.J.; Naceur, K.B.; Klem, R.C. )

    1991-07-01

    Well-performance forecasts suggests that many horizontal wells could be good candidates for matrix stimulation, even in certain reservoirs where vertical wells should be stimulated only by hydraulic fracturing. This paper presents a technique for the matrix treatment of horizontal wells to allow uniform distribution of the stimulation fluids. It involves pumping a reactive fluid through coiled tubing and an inert fluid through the coiled-tubing/well annulus. The well is completed with either a slotted liner or a cemented and perforated casing. The coiled tubing, placed at the farthest end of the well is retrieved gradually at a rate dependent on the injection rate. Both rates are calculated and are contingent upon reservoir and well properties and upon desired stimulation-fluid coverage. The complex phenomenon of acid stimulation involves different rheological properties between acid and the inert fluid, simultaneous mass transfer and reaction kinetics, and for carbonate reservoirs, such instabilities as wormhole growth. Acid-volume distributions along the well are presented for cases with and without coiled tubing. This paper details the procedures for this treatment, discusses hardware configurations, and outlines recommended fluids, additives, and rates.

  6. DWH MC 252: Subsurface Oil Transport

    NASA Astrophysics Data System (ADS)

    Beegle-Krause, C. J.; Boyer, T.; Murray, D.

    2010-12-01

    , previous research and modeling were combined to tell the story of the DWH MC 252 from the subsurface perspective. The Comprehensive Deepwater Oil and Gas model (CDOG, Yapa and Xie, 2005), and the General NOAA Operational Modeling Environment (GNOME, Beegle-Krause, 1999) were used with the NOAA Gulf of Mexico Model nowcast/forecast model to understand the 3D evolution of the subsurface spill. Model/observational comparisons are favorable, though limitations of the available models are apparent. Historical perspective on Thunder Horse (a deepwater well incident that was a dress-rehearsal for the DWH MC 252, Beegle-Krause and Walton, 2004), transitioning models from research to operations, and research needs will also be discussed.

  7. Signal Processing Techniques for a Planetary Subsurface Radar Onboard Satellite

    NASA Astrophysics Data System (ADS)

    Yagitani, S.; Ishikawa, T.; Nagano, I.; Kojima, H.; Matsumoto, H.

    2001-12-01

    We are developing a satellite-borne HF ( ~ 10 MHz) radar system to be used to investigate planetary subsurface layered structures. Before deciding the design of a high-performance subsurface radar system, in this study we calculate the propagation and reflection characteristics of various HF radar pulses through subsurface layer models, in order to examine the wave forms and frequencies of the radar pulses suitable to discriminate and pick up weak subsurface echoes buried in stronger surface reflection and scattering echoes. In the numerical calculations the wave form of a transmitted radar pulse is first Fourier-transformed into a number of elementary plane waves having different frequencies, for each of which the propagation and reflection characteristics through subsurface layer models are calculated by a full wave analysis. Then the wave form of the reflected radar echo is constructed by synthesizing all of the elementary plane waves. As the transmitted pulses, we use several different types of wave form modulation to realize the radar pulse compression to improve the signal-to-noise (S/N) ratio and time resolution of the subsurface echoes: the linear FM chirp (conventional), the M (maximal-length) sequence and the complementary sequences. We will discuss the characteristics of these pulse compression techniques, such as the improvement in the S/N ratio and the time resolution to identify the subsurface echoes. We will also present the possibility of applying the Multiple Signal Classification (MUSIC) method to further improve both the S/N ratio and time resolution to extract the weaker subsurface echoes.

  8. Remote sensing of subsurface water temperature by Raman scattering

    NASA Technical Reports Server (NTRS)

    Leonard, D. A.; Caputo, B.; Hoge, F. E.

    1979-01-01

    The application of Raman scattering to remote sensing of subsurface water temperature and salinity is considered, and both theoretical and experimental aspects of the technique are discussed. Recent experimental field measurements obtained in coastal waters and on a trans-Atlantic/Mediterranean research cruise are correlated with theoretical expectations. It is concluded that the Raman technique for remote sensing of subsurface water temperature has been brought from theoretical and laboratory stages to the point where practical utilization can now be developed.

  9. Monitoring the subsurface with quasi-static deformation

    SciTech Connect

    Sneider, Roel; Spetzler, Hartmut

    2013-09-06

    This project consisted of three sub-projects that are all aimed at monitoring the subsurface with geophysical methods. The objectives of these sub-projects are: to investigate the use of seismic waves for remote monitoring of temperature changes in the Yucca Mountain nuclear repository; to investigate the use of measured changes in the tidal tilt as a diagnostic for the infiltration of fluids in the subsurface; and to extract the electrostatic response from dynamic field fluctuations.

  10. Seismic Imaging of Open Subsurface Fractures

    NASA Astrophysics Data System (ADS)

    Myers, S. C.; Pitarka, A.; Matzel, E.; Aguiar, A. C.

    2015-12-01

    Injection of high-pressure fluid into the subsurface is proven to stimulate geothermal, oil, and gas production by opening cracks that increase permeability. The effectiveness of increasing permeability by high-pressure injection has been revolutionized by the introduction of "proppants" into the injected fluid to keep cracks open after the pressure of the stimulation activity ends. The network of fractures produced during stimulation is most commonly inferred by the location of micro-earthquakes. However, existing (closed) fractures may open aseismically, so the whole fracture network may not be imaged by micro-seismic locations alone. Further, whether all new fractures remain open and for how long remains unclear. Open cracks, even fluid-filled cracks, scatter seismic waves because traction forces are not transmitted across the gap. Numerical simulation confirms that an open crack with dimensions on the order of 10 meters can scatter enough seismic energy to change the coda of seismic signals. Our simulations show that changes in seismic coda due to newly opened fractures are only a few percent of peak seismogram amplitudes, making signals from open cracks difficult to identify. We are developing advanced signal processing methods to identify candidate signals that originate from open cracks. These methods are based on differencing seismograms that are recorded before and after high-pressure fluid injection events to identify changes in the coda. The origins of candidate signals are located using time-reversal techniques to determine if the signals are indeed associated with a coherent structure. The source of scattered energy is compared to micro-seismic event locations to determine whether cracks opened seismically or aseismically. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-675612.

  11. Controls on Microbial Transport in Subsurface Sediments

    NASA Astrophysics Data System (ADS)

    Szecsody, J. E.

    2005-12-01

    Laboratory-scale measurements of microbial transport indicate that most microbes attach to subsurface sediments. Given this attachment, it is unclear how microbes are transported significant distances in deep aquifers. It was hypothesized that attachment/detachment mechanisms are dynamic responses to nutrient availability, so that transport is dependent upon the presence/absence of electron donors and acceptors. For one microbial isolate of the Shewanella strain CN-32 there was high attachment in the presence of both electron donor and acceptor, and very little attachment if no donor or acceptor were present. In addition, CN-32 exhibited chemotatic movement through electron donor/acceptor gradients. A series of batch, 1-D homogeneous, 1-D heterogeneous, and 2-D heterogeneous experiments were conducted to quantify CN-32 Monod parameters and to assess the relative importance of simple attachment/detachment steps, dynamic growth/detachment steps, and chemotaxis. Three models included dual Monod kinetics for a single electron donor (lactate), two electron acceptors (dissolved oxygen and nitrate), and either: a) constant microbial attachment (adsorption), b) attachment linked to the presence of electron donor/acceptor, or c) chemotaxis. Simulations of batch experiments using quantified Monod parameters could not predict 1-D experimental results without accounting for microbial attachment. With constant input of electron donor/acceptors, microbial attachment could be well approximated assuming constant microbial adsorption. However, advection of input pulses of electron donor/acceptors resulted in much further downgradient migration, which could be simulated assuming an empirical growth/detachment reaction. The 2-D experimental system with microbes that received input pulses of electron donor/acceptors (idealized representation of an aquifer) showed that that both chemotaxis and the dynamic growth/detachment mechanisms were needed to approximate microbial movement over

  12. Subsurface void detection using seismic tomographic imaging

    SciTech Connect

    Gritto, Roland

    2003-06-26

    Tomographic imaging has been widely used in scientific and medical fields to remotely image media in a nondestructive way. This paper introduces a spectrum of seismic imaging applications to detect and characterize voids in coal mines. The application of seismic waves to detect changes in coal relies on two types of waves: body waves refracted along the interface between coal and bedrock (i.e., refracted P-waves) and channel waves that propagate directly through the coal (dispersive wave trains of the Rayleigh or Love type). For example, a P-wave tomography study to find underlying old mine workings in a coal mine in England, produced velocity patterns that revealed increases in velocity where high stress concentrations occur in the rock, which are most likely connected to old pillars left in support of the old working areas. At the same time, low velocities were found in areas of low stress concentrations, which are related to roof collapses indicating the locations of mined areas below. The application of channel wave tomography to directly image the presence of gaseous CO{sub 2} in a low velocity oil reservoir showed that the injected CO{sub 2} followed an ancient flow channel in the reservoir migrating from the injector to the producer well. The study showed how channel waves are preferable over refracted P-waves, as the latter were only marginally affected by the presence of the gas in the low-velocity channel. Similar approaches show great promise for the detection of voids in coal mines. Finally, a newly developed technique, based on scattering theory, revealed that the location and the size of a subsurface cavity could be accurately determined even in the presence of strong correlated and uncorrelated noise.

  13. The Measurement of Pilot Workload.

    DTIC Science & Technology

    1983-01-01

    been labeled flights A, B, and C, respectively. Each flight was flown on the same geome- try from Millville to Atlantic City, New Jersey. Table 1 de...this point, the air traffic controller briefly described to the pilot the route he/she would be flying from Millville to Atlantic City. The pilot was...presented in appendix D-i. At the conclusion of these instructions, the experimenter informed the pilot that he/she could call Millville Flight Service

  14. Lithology-dependent minimum horizontal stress and in-situ stress estimate

    NASA Astrophysics Data System (ADS)

    Zhang, Yushuai; Zhang, Jincai

    2017-04-01

    Based on the generalized Hooke's law with coupling stresses and pore pressure, the minimum horizontal stress is solved with assumption that the vertical, minimum and maximum horizontal stresses are in equilibrium in the subsurface formations. From this derivation, we find that the uniaxial strain method is the minimum value or lower bound of the minimum stress. Using Anderson's faulting theory and this lower bound of the minimum horizontal stress, the coefficient of friction of the fault is derived. It shows that the coefficient of friction may have a much smaller value than what it is commonly assumed (e.g., μf = 0.6-0.7) for in-situ stress estimate. Using the derived coefficient of friction, an improved stress polygon is drawn, which can reduce the uncertainty of in-situ stress calculation by narrowing the area of the conventional stress polygon. It also shows that the coefficient of friction of the fault is dependent on lithology. For example, if the formation in the fault is composed of weak shales, then the coefficient of friction of the fault may be small (as low as μf = 0.2). This implies that this fault is weaker and more likely to have shear failures than the fault composed of sandstones. To avoid the weak fault from shear sliding, it needs to have a higher minimum stress and a lower shear stress. That is, the critically stressed weak fault maintains a higher minimum stress, which explains why a low shear stress appears in the frictionally weak fault.

  15. Active fungi amidst a marine subsurface RNA paleome

    NASA Astrophysics Data System (ADS)

    Orsi, W.; Biddle, J.; Edgcomb, V.

    2012-12-01

    The deep marine subsurface is a vast habitat for microbial life where cells may live on geologic timescales. Since extracellular DNA in sediments may be preserved on long timescales, ribosomal RNA (rRNA) is suggested to be a proxy for the active fraction of a microbial community in the subsurface. During an investigation of eukaryotic 18S rRNA signatures by amplicon pyrosequencing, metazoan, plant, and diatom rRNA signatures were recovered from marine sediments up to 2.7 million years old, suggesting that rRNA may be much more stable than previously considered in the marine subsurface. This finding confirms the concept of a paleome, extending it to include rRNA. Within the same dataset, unique profiles of fungi were found across a range of marine subsurface provinces exhibiting statistically significant correlations with total organic carbon (TOC), sulfide, and dissolved inorganic carbon (DIC). Sequences from metazoans, plants and diatoms showed different correlation patterns, consistent with a depth-controlled paleome. The fungal correlations with geochemistry allow the inference that some fungi are active and adapted for survival in the marine subsurface. A metatranscriptomic analysis of fungal derived mRNA confirms that fungi are metabolically active and utilize a range of organic and inorganic substrates in the marine subsurface.

  16. 30 CFR 250.119 - Will MMS approve subsurface gas storage?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Will MMS approve subsurface gas storage? 250....119 Will MMS approve subsurface gas storage? The Regional Supervisor may authorize subsurface storage...: (a) Show that the subsurface storage of gas will not result in undue interference with...

  17. Feasibility study of a swept frequency electromagnetic probe (SWEEP) using inductive coupling for the determination of subsurface conductivity of the earth and water prospecting in arid regions

    NASA Technical Reports Server (NTRS)

    Latorraca, G. A.; Bannister, L. H.

    1974-01-01

    Techniques developed for electromagnetic probing of the lunar interior, and techniques developed for the generation of high power audio frequencies were combined to make practical a magnetic inductive coupling system for the rapid measurement of ground conductivity profiles which are helpful when prospecting for the presence and quality of subsurface water. A system which involves the measurement of the direction, intensity, and time phase of the magnetic field observed near the surface of the earth at a distance from a horizontal coil energized so as to create a field that penetrates the earth was designed and studied to deduce the conductivity and stratification of the subsurface. Theoretical studies and a rudimentary experiment in an arid region showed that the approach is conceptually valid and that this geophysical prospecting technique can be developed for the economical exploration of subterranean water resources.

  18. Dynamics of Fe(II), sulphur and phosphate in pilot-scale constructed wetlands treating a sulphate-rich chlorinated hydrocarbon contaminated groundwater.

    PubMed

    Wu, Shubiao; Chen, Zhongbing; Braeckevelt, Mareike; Seeger, Eva M; Dong, Renjie; Kästner, Matthias; Paschke, Heidrun; Hahn, Anja; Kayser, Gernot; Kuschk, Peter

    2012-04-15

    Long-term investigations were carried out in two pilot-scale horizontal subsurface flow constructed wetlands (planted and unplanted) with an iron-rich soil matrix for treating sulphate-rich groundwater which was contaminated with low concentrations of chlorinated hydrocarbons. The temporal and spatial dynamics of pore-water sulphide, Fe(II) and phosphate concentrations in the wetland beds were characterized and the seasonal effects on sulphide production and nitrification inhibition were evaluated. The results demonstrated that the pore-water sulphide concentrations gradually increased from less than 0.2 mg/L in 2005 to annual average concentrations of 15 mg/L in 2010, while the pore-water Fe(II) concentrations decreased from 35.4 mg/L to 0.3 mg/L. From 2005 to 2010, the phosphate removal efficiency declined from 91% to 10% under a relatively constant inflow concentration of 5 mg/L. The pronounced effect of plants was accompanied by a higher sulphate reduction and ammonium oxidation in the planted bed, as compared to the unplanted control. A high tolerance of plants towards sulphide toxicity was observed, which might be due to the detoxification of sulphide by oxygen released by the roots. However, during the period of 2009-2010, the nitrification was negatively impacted by the sulphide production as the reduction in the removal of ammonium from 75% to 42% (with inflow concentration of 55 mg/L) correlated with the increasing mean annual sulphide concentrations. The effect of the detoxification of sulphide and the immobilization of phosphate by the application of the iron-rich soil matrix in the initial years was proven; however, the life-span of this effect should not only be taken into consideration in further design but also in scientific studies.

  19. Large, horizontal-axis wind turbines

    NASA Technical Reports Server (NTRS)

    Linscott, B. S.; Perkins, P.; Dennett, J. T.

    1984-01-01

    Development of the technology for safe, reliable, environmentally acceptable large wind turbines that have the potential to generate a significant amount of electricity at costs competitive with conventional electric generating systems are presented. In addition, these large wind turbines must be fully compatible with electric utility operations and interface requirements. There are several ongoing large wind system development projects and applied research efforts directed toward meeting the technology requirements for utility applications. Detailed information on these projects is provided. The Mod-O research facility and current applied research effort in aerodynamics, structural dynamics and aeroelasticity, composite and hybrid composite materials, and multiple system interaction are described. A chronology of component research and technology development for large, horizontal axis wind turbines is presented. Wind characteristics, wind turbine economics, and the impact of wind turbines on the environment are reported. The need for continued wind turbine research and technology development is explored. Over 40 references are sited and a bibliography is included.

  20. Method for horizontally growing ribbon crystal

    NASA Technical Reports Server (NTRS)

    Kudo, B.

    1980-01-01

    A high speed method for forming ribbon crystal of desired width and thickness is characterized by drawing out the ribbon through a space whose distance is 5.7 times that of the thickness of the grown ribbon. The ribbon is drawn out between the molten body of the lower surface and the tip of the upper surface of the seed crystal and growing crystal. The ribbon growing at the tip of the seed crystal is drawn out horizontally and centrifugally by controlling the amount of cooling and heating. The temperature is maintained about equal to the upper surface of the outlets from which the molten substance is drawn, at least in certain portions of the crucible rim, the rim is elevated to prevent dropping of the molten raw material.

  1. Horizontal gene transfer: A critical view

    PubMed Central

    Kurland, C. G.; Canback, B.; Berg, Otto G.

    2003-01-01

    It has been suggested that horizontal gene transfer (HGT) is the “essence of phylogeny.” In contrast, much data suggest that this is an exaggeration resulting in part from a reliance on inadequate methods to identify HGT events. In addition, the assumption that HGT is a ubiquitous influence throughout evolution is questionable. Instead, rampant global HGT is likely to have been relevant only to primitive genomes. In modern organisms we suggest that both the range and frequencies of HGT are constrained most often by selective barriers. As a consequence those HGT events that do occur most often have little influence on genome phylogeny. Although HGT does occur with important evolutionary consequences, classical Darwinian lineages seem to be the dominant mode of evolution for modern organisms. PMID:12902542

  2. Horizontal Gene Transfer, Dispersal and Haloarchaeal Speciation

    PubMed Central

    Papke, R. Thane; Corral, Paulina; Ram-Mohan, Nikhil; de la Haba, Rafael R.; Sánchez-Porro, Cristina; Makkay, Andrea; Ventosa, Antonio

    2015-01-01

    The Halobacteria are a well-studied archaeal class and numerous investigations are showing how their diversity is distributed amongst genomes and geographic locations. Evidence indicates that recombination between species continuously facilitates the arrival of new genes, and within species, it is frequent enough to spread acquired genes amongst all individuals in the population. To create permanent independent diversity and generate new species, barriers to recombination are probably required. The data support an interpretation that rates of evolution (e.g., horizontal gene transfer and mutation) are faster at creating geographically localized variation than dispersal and invasion are at homogenizing genetic differences between locations. Therefore, we suggest that recurrent episodes of dispersal followed by variable periods of endemism break the homogenizing forces of intrapopulation recombination and that this process might be the principal stimulus leading to divergence and speciation in Halobacteria. PMID:25997110

  3. Horizontal Gene Exchange in Environmental Microbiota

    PubMed Central

    Aminov, Rustam I.

    2011-01-01

    Horizontal gene transfer (HGT) plays an important role in the evolution of life on the Earth. This view is supported by numerous occasions of HGT that are recorded in the genomes of all three domains of living organisms. HGT-mediated rapid evolution is especially noticeable among the Bacteria, which demonstrate formidable adaptability in the face of recent environmental changes imposed by human activities, such as the use of antibiotics, industrial contamination, and intensive agriculture. At the heart of the HGT-driven bacterial evolution and adaptation are highly sophisticated natural genetic engineering tools in the form of a variety of mobile genetic elements (MGEs). The main aim of this review is to give a brief account of the occurrence and diversity of MGEs in natural ecosystems and of the environmental factors that may affect MGE-mediated HGT. PMID:21845185

  4. Conjugate natural convection between horizontal eccentric cylinders

    NASA Astrophysics Data System (ADS)

    Nasiri, Davood; Dehghan, Ali Akbar; Hadian, Mohammad Reza

    2017-03-01

    This study involved the numerical investigation of conjugate natural convection between two horizontal eccentric cylinders. Both cylinders were considered to be isothermal with only the inner cylinder having a finite wall thickness. The momentum and energy equations were discretized using finite volume method and solved by employing SIMPLER algorithm. Numerical results were presented for various solid-fluid conductivity ratios ( KR) and various values of eccentricities in different thickness of inner cylinder wall and also for different angular positions of inner cylinder. From the results, it was observed that in an eccentric case, and for KR < 10, an increase in thickness of inner cylinder wall resulted in a decrease in the average equivalent conductivity coefficient (overline{{K_{eq} }}); however, a KR > 10 value caused an increase in overline{{K_{eq} }}. It was also concluded that in any angular position of inner cylinder, the value of overline{{K_{eq} }} increased with increase in the eccentricity.

  5. Passive magnetic bearing for a horizontal shaft

    DOEpatents

    Post, Richard F.

    2003-12-02

    A passive magnetic bearing is composed of a levitation element and a restorative element. The levitation element is composed of a pair of stationary arcuate ferromagnetic segments located within an annular radial-field magnet array. The magnet array is attached to the inner circumference of a hollow shaft end. An attractive force between the arcuate segments and the magnet array acts vertically to levitate the shaft, and also in a horizontal transverse direction to center the shaft. The restorative element is comprised of an annular Halbach array of magnets and a stationary annular circuit array located within the Halbach array. The Halbach array is attached to the inner circumference of the hollow shaft end. A repulsive force between the Halbach array and the circuit array increases inversely to the radial space between them, and thus acts to restore the shaft to its equilibrium axis of rotation when it is displaced therefrom.

  6. Horizontal Drop of 21- PWR Waste Package

    SciTech Connect

    A.K. Scheider

    2007-01-31

    The objective of this calculation is to determine the structural response of the waste package (WP) dropped horizontally from a specified height. The WP used for that purpose is the 21-Pressurized Water Reactor (PWR) WP. The scope of this document is limited to reporting the calculation results in-terms of stress intensities. This calculation is associated with the WP design and was performed by the Waste Package Design group in accordance with the ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 16). AP-3.12Q, ''Calculations'' (Ref. 1 1) is used to perform the calculation and develop the document. The sketches attached to this calculation provide the potential dimensions and materials for the 21-PWR WP design.

  7. Horizontal gene transfer in parasitic plants.

    PubMed

    Davis, Charles C; Xi, Zhenxiang

    2015-08-01

    Horizontal gene transfer (HGT) between species has been a major focus of plant evolutionary research during the past decade. Parasitic plants, which establish a direct connection with their hosts, have provided excellent examples of how these transfers are facilitated via the intimacy of this symbiosis. In particular, phylogenetic studies from diverse clades indicate that parasitic plants represent a rich system for studying this phenomenon. Here, HGT has been shown to be astonishingly high in the mitochondrial genome, and appreciable in the nuclear genome. Although explicit tests remain to be performed, some transgenes have been hypothesized to be functional in their recipient species, thus providing a new perspective on the evolution of novelty in parasitic plants.

  8. Intercellular Genomics of Subsurface Microbial Colonies

    SciTech Connect

    Ortoleva, Peter; Tuncay, Kagan; Gannon, Dennis; Meile, Christof

    2007-02-14

    This report summarizes progress in the second year of this project. The objective is to develop methods and software to predict the spatial configuration, properties and temporal evolution of microbial colonies in the subsurface. To accomplish this, we integrate models of intracellular processes, cell-host medium exchange and reaction-transport dynamics on the colony scale. At the conclusion of the project, we aim to have the foundations of a predictive mathematical model and software that captures the three scales of these systems – the intracellular, pore, and colony wide spatial scales. In the second year of the project, we refined our transcriptional regulatory network discovery (TRND) approach that utilizes gene expression data along with phylogenic similarity and gene ontology analyses and applied it successfully to E.coli, human B cells, and Geobacter sulfurreducens. We have developed a new Web interface, GeoGen, which is tailored to the reconstruction of microbial TRNs and solely focuses on Geobacter as one of DOE’s high priority microbes. Our developments are designed such that the frameworks for the TRND and GeoGen can readily be used for other microbes of interest to the DOE. In the context of modeling a single bacterium, we are actively pursuing both steady-state and kinetic approaches. The steady-state approach is based on a flux balance that uses maximizing biomass growth rate as its objective, subjected to various biochemical constraints, for the optimal values of reaction rates and uptake/release of metabolites. For the kinetic approach, we use Karyote, a rigorous cell model developed by us for an earlier DOE grant and the DARPA BioSPICE Project. We are also investigating the interplay between bacterial colonies and environment at both pore and macroscopic scales. The pore scale models use detailed representations for realistic porous media accounting for the distribution of grain size whereas the macroscopic models employ the Darcy-type flow

  9. Geophysical subsurface imaging and interface identification.

    SciTech Connect

    Pendley, Kevin; Bochev, Pavel Blagoveston; Day, David Minot; Robinson, Allen Conrad; Weiss, Chester Joseph

    2005-09-01

    Electromagnetic induction is a classic geophysical exploration method designed for subsurface characterization--in particular, sensing the presence of geologic heterogeneities and fluids such as groundwater and hydrocarbons. Several approaches to the computational problems associated with predicting and interpreting electromagnetic phenomena in and around the earth are addressed herein. Publications resulting from the project include [31]. To obtain accurate and physically meaningful numerical simulations of natural phenomena, computational algorithms should operate in discrete settings that reflect the structure of governing mathematical models. In section 2, the extension of algebraic multigrid methods for the time domain eddy current equations to the frequency domain problem is discussed. Software was developed and is available in Trilinos ML package. In section 3 we consider finite element approximations of De Rham's complex. We describe how to develop a family of finite element spaces that forms an exact sequence on hexahedral grids. The ensuing family of non-affine finite elements is called a van Welij complex, after the work [37] of van Welij who first proposed a general method for developing tangentially and normally continuous vector fields on hexahedral elements. The use of this complex is illustrated for the eddy current equations and a conservation law problem. Software was developed and is available in the Ptenos finite element package. The more popular methods of geophysical inversion seek solutions to an unconstrained optimization problem by imposing stabilizing constraints in the form of smoothing operators on some enormous set of model parameters (i.e. ''over-parametrize and regularize''). In contrast we investigate an alternative approach whereby sharp jumps in material properties are preserved in the solution by choosing as model parameters a modest set of variables which describe an interface between adjacent regions in physical space. While

  10. Seismic Techniques for Subsurface Voids Detection

    NASA Astrophysics Data System (ADS)

    Gritto, Roland; Korneev, Valeri; Elobaid Elnaiem, Ali; Mohamed, Fathelrahman; Sadooni, Fadhil

    2016-04-01

    orthogonal transmission surveys to detect and locate the object. Furthermore, we showed that ambient noise recordings may generate data with sufficient signal-to-noise ratio to successfully detect and locate subsurface voids. Being able to use ambient noise recordings would eliminate the need to employ active seismic sources that are time consuming and more expensive to operate.

  11. Microbial Field Pilot Study

    SciTech Connect

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1990-11-01

    This report covers progress made during the first year of the Microbial Field Pilot Study project. Information on reservoir ecology and characterization, facility and treatment design, core experiments, bacterial mobility, and mathematical modeling are addressed. To facilitate an understanding of the ecology of the target reservoir analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. A preliminary design of facilities for the operation of the field pilot test was prepared. In addition, procedures for facilities installation and for injection treatments are described. The Southeast Vassar Vertz Sand Unit (SEVVSU), the site of the proposed field pilot study, is described physically, historically, and geologically. The fields current status is presented and the ongoing reservoir simulation is discussed. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. Two possible mechanisms, relative permeability effects and changes in the capillary number, are discussed and related to four Berea core experiments' results. The experiments were conducted at reservoir temperature using SEVVSU oil, brine, and bacteria. The movement and activity of bacteria in porous media were investigated by monitoring the growth of bacteria in sandpack cores under no flow conditions. The rate of bacteria advancement through the cores was determined. A mathematical model of the MEOR process has been developed. The model is a three phase, seven species, one dimensional model. Finite difference methods are used for solution. Advection terms in balance equations are represented with a third- order upwind differencing scheme to reduce numerical dispersion and oscillations. The model is applied to a batch fermentation example. 52 refs., 26 figs., 21 tabs.

  12. Microbial field pilot study

    SciTech Connect

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  13. Microbial field pilot study

    SciTech Connect

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  14. Advanced Simulator for Pilot Training: Effects of Collimation on Accommodation and Vergence

    DTIC Science & Technology

    1985-09-01

    Training ( ASPT ), used for training R&D by AFHRL, employs seven collimated display windows to provide a virtual image covering a 300 degree horizontal by...with relatively low luminance and contrast. One potential solution to the limited lumirance and contrast of the ASPT display system is simply to remove...while viewing ASPT imagery through a ILIOS. Measurements were made while the observer viewed a dynamic computer-generated scene representing the pilot’s

  15. Microbial field pilot study

    SciTech Connect

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.

    1991-12-06

    The objective of this project is to perform a microbial enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. During this quarter an additional tracer study was performed in the field to determine pre-treatment flow paths and the first nutrients were injected. 2 figs.

  16. Pilot climate data system

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A usable data base, the Pilot climate Data System (PCDS) is described. The PCDS is designed to be an interactive, easy-to-use, on-line generalized scientific information system. It efficiently provides uniform data catalogs; inventories, and access method, as well as manipulation and display tools for a large assortment of Earth, ocean and atmospheric data for the climate-related research community. Researchers can employ the PCDS to scan, manipulate, compare, display, and study climate parameters from diverse data sets. Software features, and applications of the PCDS are highlighted.

  17. Scenario simulation based assessment of subsurface energy storage

    NASA Astrophysics Data System (ADS)

    Beyer, C.; Bauer, S.; Dahmke, A.

    2014-12-01

    Energy production from renewable sources such as solar or wind power is characterized by temporally varying power supply. The politically intended transition towards renewable energies in Germany („Energiewende") hence requires the installation of energy storage technologies to compensate for the fluctuating production. In this context, subsurface energy storage represents a viable option due to large potential storage capacities and the wide prevalence of suited geological formations. Technologies for subsurface energy storage comprise cavern or deep porous media storage of synthetic hydrogen or methane from electrolysis and methanization, or compressed air, as well as heat storage in shallow or moderately deep porous formations. Pressure build-up, fluid displacement or temperature changes induced by such operations may affect local and regional groundwater flow, geomechanical behavior, groundwater geochemistry and microbiology. Moreover, subsurface energy storage may interact and possibly be in conflict with other "uses" like drinking water abstraction or ecological goods and functions. An utilization of the subsurface for energy storage therefore requires an adequate system and process understanding for the evaluation and assessment of possible impacts of specific storage operations on other types of subsurface use, the affected environment and protected entities. This contribution presents the framework of the ANGUS+ project, in which tools and methods are developed for these types of assessments. Synthetic but still realistic scenarios of geological energy storage are derived and parameterized for representative North German storage sites by data acquisition and evaluation, and experimental work. Coupled numerical hydraulic, thermal, mechanical and reactive transport (THMC) simulation tools are developed and applied to simulate the energy storage and subsurface usage scenarios, which are analyzed for an assessment and generalization of the imposed THMC

  18. How does subsurface characterization affect simulations of hyporheic exchange?

    PubMed

    Ward, Adam S; Gooseff, Michael N; Singha, Kamini

    2013-01-01

    We investigated the role of increasingly well-constrained geologic structures in the subsurface (i.e., subsurface architecture) in predicting streambed flux and hyporheic residence time distribution (RTD) for a headwater stream. Five subsurface realizations with increasingly resolved lithological boundaries were simulated in which model geometries were based on increasing information about flow and transport using soil and geologic maps, surface observations, probing to depth to refusal, seismic refraction, electrical resistivity (ER) imaging of subsurface architecture, and time-lapse ER imaging during a solute tracer study. Particle tracking was used to generate RTDs for each model run. We demonstrate how improved characterization of complex lithological boundaries and calibration of porosity and hydraulic conductivity affect model prediction of hyporheic flow and transport. Models using hydraulic conductivity calibrated using transient ER data yield estimates of streambed flux that are three orders of magnitude larger than uncalibrated models using estimated values for hydraulic conductivity based on values published for nearby hillslopes (10(-4) vs. 10(-7) m(2)/s, respectively). Median residence times for uncalibrated and calibrated models are 10(3) and 10(0) h, respectively. Increasingly well-resolved subsurface architectures yield wider hyporheic RTDs, indicative of more complex hyporheic flowpath networks and potentially important to biogeochemical cycling. The use of ER imaging to monitor solute tracers informs subsurface structure not apparent from other techniques, and helps to define transport properties of the subsurface (i.e., hydraulic conductivity). Results of this study demonstrate the value of geophysical measurements to more realistically simulate flow and transport along hyporheic flowpaths.

  19. Evaluation on the Efficiency of Subsurface Drainage in Chiu-Fen Landslide at Northern Taiwan

    NASA Astrophysics Data System (ADS)

    Ying, L. Y.; Lin, D. G.

    2015-12-01

    For administrative district, the Chiu-Fen landslide is situated at northern Taiwan and comes within the jurisdiction of Ruei-Fang district, New Taipei City Government. Chiu-Fen village is a famous spot for sightseeing and tourism in Southeast Asia. In the last decade, for economic purpose, a vast area of slope land in Chiu-Fen area was reclaimed into business and commercial districts. However, due to the complicated geological and hydrological conditions, improper reclamation, and lack of appropriate soil and water conservation facilities, large scale landslides are frequently triggered by typhoon rainfall and causes damages to the transportation and residential building in the community. As a consequence, the government initiated a comprehensive field investigations and remediation plans to stabilize the landslide from 1997 and the remediation works were concentrated on subsurface drainages, namely the application of drainage well (a vertical shaft with multi-level horizontal drainage boreholes). To investigate the efficiency of drainage wells on the landslide, the A1-profile in the landslide which covers the drainage wells W2 and W4 was selected for a series of rainfall seepage and slope stability analyses. In addition, a 48-hrs design rainfall with return period of 25, 50 and 100 years based on the local meteorological data bank was adopted for the analyses. The numerical results indicate the factor safety FS of the three potential sliding surfaces within A1-profile are constantly keeping greater than one (FS > 1.0) and without decreasing with the elapsed time during rainfall. This implies that the subsurface drainage works can drain off the infiltrated rainwater from a high intensity and long duration rainfall and preserve the slope stability of landslides from deterioration. Finally, the efficiency of the drainage wells can be evaluated quantitatively in terms of the time-dependent factor of safety and the pore water pressure distribution on several potential

  20. Effect of Extent of Natural Subsurface Bioreduction on Fe-mineralogy of Subsurface Sediments

    SciTech Connect

    Kukkadapu, Ravi K.; Qafoku, Nikolla; Arey, Bruce W.; Resch, Charles T.; Long, Philip E.

    2010-05-16

    Naturally bioreduced zones with considerable sorbed U were recently identified at a former U mining and processing site at Rifle, CO, USA. Most of the sorbed U appears to be associated with Fe minerals. Variably reduced sediment samples were analyzed by suite of techniques, primarily by room temperature Mössbauer spectroscopy. Fe-oxides of different types and crystallinity, and Fe(II)/Fe(III)-containing clays are dominant in all the sediments. The amounts of poorly crystalline Fe(III)-oxide, however, was lower in the reduced samples. In addition, framboidal pyrites with sorbed U were common in the highly reduced sediments. Overall, the information gained from this work may help develop design field strategies for immobilization and stabilization of U(VI) in contaminated subsurface environments.

  1. Motivational Engineering for Pilot Training.

    ERIC Educational Resources Information Center

    Herzberg, Frederick I.; And Others

    The study was an investigation of student pilot motivation for, and toward, the Air Training Command's undergraduate pilot training (UPT) program. The motivation hygiene approach was used to identify the motivational factors operating in the UPT program systematically. This approach has been used extensively in industry and with success in a…

  2. Horizontal spatial correlation of hydraulic and reactive transport parameters as related to hierarchical sedimentary architecture at the Borden research site

    NASA Astrophysics Data System (ADS)

    Ritzi, R. W.; Huang, L.; Ramanathan, R.; Allen-King, R. M.

    2013-04-01

    Highly resolved data from the Borden research site provide a unique opportunity to study the horizontal spatial bivariate correlation of hydraulic and reactive attributes affecting subsurface transport. The data also allow quantitatively relating this correlation to the hierarchical sedimentary architecture of the aquifer. The data include collocated samples of log permeability, Y, the log of the perchloroethene sorption distribution coefficient, Ξ, and lithologic unit type. The horizontal Y and Ξ autosemivariograms and the Ξ-Y cross-semivariogram have the same underlying correlation structure (shape and range in the rise to a sill). The common structure is not due to Ξ-Y point correlation or in-unit spatial correlation. The common structure is defined by how the proportion of lag transitions crossing different unit types (i.e., the cross-transition probability structure) increases with increasing lag distance. The common underlying cross-transition structure contains two substructures with different correlation ranges corresponding to two scales of unit types within the sedimentary architecture. For each substructure, a large standard deviation in the length of units relative to the mean length gives rise to an exponential-like shape and the proportions and mean length of units define the ranges. The horizontal Ξ-Y spatial cross correlation is primarily defined by the larger-scale substructure and the differences in mean Ξ and Y between larger-scale unit types.

  3. Mapping bedrock surface contours using the horizontal-to-vertical spectral ratio (HVSR) method near the middle quarter srea, Woodbury, Connecticut

    USGS Publications Warehouse

    Brown, Craig J.; Voytek, Emily B.; Lane, Jr., John W.; Stone, Janet R.

    2013-01-01

    The bedrock surface contours in Woodbury, Connecticut, were determined downgradient of a commercial zone known as the Middle Quarter area (MQA) using the novel, noninvasive horizontal-to-vertical (H/V) spectral ratio (HVSR) passive seismic geophysical method. Boreholes and monitoring wells had been drilled in this area to characterize the shallow subsurface to within 20 feet (ft) of the land surface, but little was known about the deep subsurface, including sediment thicknesses and depths to bedrock (Starn and Brown, 2007; Brown and others, 2009). Improved information on the altitude of the bedrock surface and its spatial variation was needed for assessment and remediation of chlorinated solvents that have contaminated the overlying glacial aquifer that supplies water to wells in the area.

  4. ICAAS piloted simulation results

    NASA Astrophysics Data System (ADS)

    Landy, R. J.; Halski, P. J.; Meyer, R. P.

    1994-05-01

    This paper reports piloted simulation results from the Integrated Control and Avionics for Air Superiority (ICAAS) piloted simulation evaluations. The program was to develop, integrate, and demonstrate critical technologies which will enable United States Air Force tactical fighter 'blue' aircraft to achieve superiority and survive when outnumbered by as much as four to one by enemy aircraft during air combat engagements. Primary emphasis was placed on beyond visual range (BVR) combat with provisions for effective transition to close-in combat. The ICAAS system was developed and tested in two stages. The first stage, called low risk ICAAS, was defined as employing aircraft and avionics technology with an initial operational date no later than 1995. The second stage, called medium risk ICAAS, was defined as employing aircraft and avionics technology with an initial operational date no later than 1998. Descriptions of the low risk and medium risk simulation configurations are given. Normalized (unclassified) results from both the low risk and medium risk ICAAS simulations are discussed. The results show the ICAAS system provided a significant improvement in air combat performance when compared to a current weapon system. Data are presented for both current generation and advanced fighter aircraft. The ICAAS technologies which are ready for flight testing in order to transition to the fighter fleet are described along with technologies needing additional development.

  5. Thoracolumbar pain among fighter pilots.

    PubMed

    Hämäläinen, O

    1999-08-01

    High +Gz forces place high stress on the spinal column, and fighter pilots flying high-performance fighter aircraft frequently] report work-related thoracic and lumbar spine pain. The aim of this study was to determine whether +Gz exposure causes work-related thoracolumbar spine pain among fighter pilots. A questionnaire was used to establish the occurrence of thoracic and lumbar spine pain during the preceding 12 months and during duties over the whole working career among 320 fighter pilots and 283 nonflying controls matched for age and sex. Thirty-two percent of the pilots and 19% of the controls had experienced pain in the thoracic spine during the preceding 12 months (odds ratio [OR] = 2.3; 95% confidence interval [CI] = 1.5-3.5; p = 0.002 for the pilots). Among the pilots, the OR increased up to 6.1 (95% CI = 1.6-23.1; p = 0.0007) with the number of +Gz flight hours. There was no difference between the groups with regard to lumbar pain during the preceding 12 months, but over their whole working careers fighter pilots (58%) had experienced lumbar pain during their duties more often than controls (48%) (OR = 1.8; 95% CI = 1.3-2.6; p = 0.002). The greater the number of +Gz flight hours, the greater the occurrence of lumbar spine pain when on duty (OR = 26.9; 95% CI = 6.2-116; p = 0.0001 for the most experienced fighter pilots). The same was not true with regard to the number of +Gz flight hours and lumbar pain during the preceding 12 months. Age had no effect on pain in the thoracic or lumbar spine. Fighter pilots flying high-performance aircraft have more work-related thoracic and lumbar spine pain than controls of the same age and sex. The difference is explained by the pilots' exposure to +Gz forces.

  6. Microbial iron-redox cycling in subsurface environments.

    PubMed

    Roden, Eric E

    2012-12-01

    In addition to its central role in mediating electron-transfer reactions within all living cells, iron undergoes extracellular redox transformations linked to microbial energy generation through utilization of Fe(II) as a source of chemical energy or Fe(III) as an electron acceptor for anaerobic respiration. These processes permit microbial populations and communities to engage in cyclic coupled iron oxidation and reduction within redox transition zones in subsurface environments. In the present paper, I review and synthesize a few case studies of iron-redox cycling in subsurface environments, highlighting key biochemical aspects of the extracellular iron-redox metabolisms involved. Of specific interest are the coupling of iron oxidation and reduction in field and experimental systems that model redox gradients and fluctuations in the subsurface, and novel pathways and organisms involved in the redox cycling of insoluble iron-bearing minerals. These findings set the stage for rapid expansion in our knowledge of the range of extracellular electron-transfer mechanisms utilized by subsurface micro-organisms. The observation that closely coupled oxidation and reduction of iron can take place under conditions common to the subsurface motivates this expansion in pursuit of molecular tools for studying iron-redox cycling communities in situ.

  7. Lower-Temperature Subsurface Layout and Ventilation Concepts

    SciTech Connect

    Christine L. Linden; Edward G. Thomas

    2001-06-20

    This analysis combines work scope identified as subsurface facility (SSF) low temperature (LT) Facilities System and SSF LT Ventilation System in the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M&O 2001b, pp. 6 and 7, and pp. 13 and 14). In accordance with this technical work plan (TWP), this analysis is performed using AP-3.10Q, Analyses and Models. It also incorporates the procedure AP-SI.1Q, Software Management. The purpose of this analysis is to develop an overall subsurface layout system and the overall ventilation system concepts that address a lower-temperature operating mode for the Monitored Geologic Repository (MGR). The objective of this analysis is to provide a technical design product that supports the lower-temperature operating mode concept for the revision of the system description documents and to provide a basis for the system description document design descriptions. The overall subsurface layout analysis develops and describes the overall subsurface layout, including performance confirmation facilities (also referred to as Test and Evaluation Facilities) for the Site Recommendation design. This analysis also incorporates current program directives for thermal management.

  8. Scale invariance of subsurface flow patterns and its limitation

    NASA Astrophysics Data System (ADS)

    Hergarten, S.; Winkler, G.; Birk, S.

    2016-05-01

    Preferential flow patterns in the subsurface are of great importance for the availability and the quality of water resources. However, knowledge of their spatial structure is still behind their importance, so that understanding the nature of preferential flow patterns is a major issue in subsurface hydrology. Comparing the statistics of river catchment sizes and spring discharges, we found that the morphology of preferential subsurface flow patterns is probably scale invariant and similar to that of dendritic river networks. This result is not limited to karstic aquifers where the occurrence of dendritic structures has been known at least qualitatively for a long time. The scale invariance even seems to be independent of the lithology of the aquifer. However, scale invariance of river patterns seems to be only limited by the continental scale, while scale invariance of subsurface flow patterns breaks down at much smaller scales. The upper limit of scale invariance in subsurface flow patterns is highly variable. We found a range from thousands of square kilometers for limestone aquifers down to less than 1 km2 in the weathered zone and debris accumulations of crystalline rocks.

  9. Plasmid incidence in bacteria from deep subsurface sediments

    SciTech Connect

    Fredrickson, J.K.; Hicks, R.J.; Li, S.W.; Brockman, F.J. )

    1988-12-01

    Bacteria were isolated from deep terrestrial subsurface sediments underlying the coastal plain of South Carolina. A total of 163 isolates from deep sediments, surface soil, and return drill muds were examined for plasmid DNA content and resistance to the antibiotics penicillin, ampicillin, carbenicillin, streptomycin, kanamycin, and tetracycline. MICs of Cu{sup 2+}, Cr{sup 3+}, and Hg{sup 2+} for each isolate were also determined. The overall frequency of plasmid occurrence in the subsurface bacteria was 33%. Resistance was most frequent to penicillin (70% of all isolates), ampicillin (49%), and carbenicillin (32%) and was concluded to be related to the concentrations of the individual antibiotics in the disks used for assaying resistance and to the production of low levels of {beta}-lactamase. The frequencies of resistance to penicillin and ampicillin were significantly greater for isolates bearing plasmids than for plasmidless isolates; however, resistance was not transferable to penicillin-sensitive Escherichia coli. Hybridization of subsurface bacterial plasmids and chromosomal DNA with a whole-TOL-plasmid (pWWO) probe revealed some homology of subsurface bacterial plasmid and chromosomal DNAs, indicating a potential for those bacterial to harbor catabolic genes on plasmids or chromosomes. The incidences of antibiotic resistance and MICs of metals for subsurface bacteria were significantly different from those drill mud bacteria, ruling out the possibility that bacteria from sediments were derived from drill muds.

  10. Nematoda from the terrestrial deep subsurface of South Africa

    NASA Astrophysics Data System (ADS)

    Borgonie, G.; García-Moyano, A.; Litthauer, D.; Bert, W.; Bester, A.; van Heerden, E.; Möller, C.; Erasmus, M.; Onstott, T. C.

    2011-06-01

    Since its discovery over two decades ago, the deep subsurface biosphere has been considered to be the realm of single-cell organisms, extending over three kilometres into the Earth's crust and comprising a significant fraction of the global biosphere. The constraints of temperature, energy, dioxygen and space seemed to preclude the possibility of more-complex, multicellular organisms from surviving at these depths. Here we report species of the phylum Nematoda that have been detected in or recovered from 0.9-3.6-kilometre-deep fracture water in the deep mines of South Africa but have not been detected in the mining water. These subsurface nematodes, including a new species, Halicephalobus mephisto, tolerate high temperature, reproduce asexually and preferentially feed upon subsurface bacteria. Carbon-14 data indicate that the fracture water in which the nematodes reside is 3,000-12,000-year-old palaeometeoric water. Our data suggest that nematodes should be found in other deep hypoxic settings where temperature permits, and that they may control the microbial population density by grazing on fracture surface biofilm patches. Our results expand the known metazoan biosphere and demonstrate that deep ecosystems are more complex than previously accepted. The discovery of multicellular life in the deep subsurface of the Earth also has important implications for the search for subsurface life on other planets in our Solar System.

  11. Integrated Surface/subsurface flow modeling in PFLOTRAN

    SciTech Connect

    Painter, Scott L

    2016-10-01

    Understanding soil water, groundwater, and shallow surface water dynamics as an integrated hydrological system is critical for understanding the Earth’s critical zone, the thin outer layer at our planet’s surface where vegetation, soil, rock, and gases interact to regulate the environment. Computational tools that take this view of soil moisture and shallow surface flows as a single integrated system are typically referred to as integrated surface/subsurface hydrology models. We extend the open-source, highly parallel, subsurface flow and reactive transport simulator PFLOTRAN to accommodate surface flows. In contrast to most previous implementations, we do not represent a distinct surface system. Instead, the vertical gradient in hydraulic head at the land surface is neglected, which allows the surface flow system to be eliminated and incorporated directly into the subsurface system. This tight coupling approach leads to a robust capability and also greatly simplifies implementation in existing subsurface simulators such as PFLOTRAN. Successful comparisons to independent numerical solutions build confidence in the approximation and implementation. Example simulations of the Walker Branch and East Fork Poplar Creek watersheds near Oak Ridge, Tennessee demonstrate the robustness of the approach in geometrically complex applications. The lack of a robust integrated surface/subsurface hydrology capability had been a barrier to PFLOTRAN’s use in critical zone studies. This work addresses that capability gap, thus enabling PFLOTRAN as a community platform for building integrated models of the critical zone.

  12. [EEG-correlates of pilots' functional condition in simulated flight dynamics].

    PubMed

    Kiroy, V N; Aslanyan, E V; Bakhtin, O M; Minyaeva, N R; Lazurenko, D M

    2015-01-01

    The spectral characteristics of the EEG recorded on two professional pilots in the simulator TU-154 aircraft in flight dynamics, including takeoff, landing and horizontal flight (in particular during difficult conditions) were analyzed. EEG recording was made with frequency band 0.1-70 Hz continuously from 15 electrodes. The EEG recordings were evaluated using analysis of variance and discriminant analysis. Statistical significant of the identified differences and the influence of the main factors and their interactions were evaluated using Greenhouse - Gaiser corrections. It was shown that the spectral characteristics of the EEG are highly informative features of the state of the pilots, reflecting the different flight phases. High validity ofthe differences including individual characteristic, indicates their non-random nature and the possibility of constructing a system of pilots' state control during all phases of flight, based on EEG features.

  13. On the impact of the resolution on the surface and subsurface Eastern Tropical Atlantic warm bias

    NASA Astrophysics Data System (ADS)

    Martín-Rey, Marta; Lazar, Alban

    2016-04-01

    The tropical variability has a great importance for the climate of adjacent areas. Its sea surface temperature anomalies (SSTA) affect in particular the Brazilian Nordeste and the Sahelian region, as well as the tropical Pacific or the Euro-Atlantic sector. Nevertheless, the state-of the art climate models exhibits very large systematic errors in reproducing the seasonal cycle and inter-annual variability in the equatorial and coastal Africa upwelling zones (up to several °C for SST). Theses biases exist already, in smaller proportions though, in forced ocean models (several 1/10th of °C), and affect not only the mixed layer but also the whole thermocline. Here, we present an analysis of the impact of horizontal and vertical resolution changes on these biases. Three different DRAKKAR NEMO OGCM simulations have been analysed, associated to the same forcing set (DFS4.4) with different grid resolutions: "REF" for reference (1/4°, 46 vertical levels), "HH" with a finer horizontal grid (1/12°, 46 v.l.) and "HV" with a finer vertical grid (1/4°, 75 v.l.). At the surface, a more realistic seasonal SST cycle is produced in HH in the three upwellings, where the warm bias decreases (by 10% - 20%) during boreal spring and summer. A notable result is that increasing vertical resolution in HV causes a shift (in advance) of the upwelling SST seasonal cycles. In order to better understand these results, we estimate the three upwelling subsurface temperature errors, using various in-situ datasets, and provide thus a three-dimensional view of the biases.

  14. Pilot-Scale Demonstration of In-Situ Chemical Oxidation ...

    EPA Pesticide Factsheets

    A pilot-scale in situ chemical oxidation (ISCO) demonstration, involving subsurface injections of sodium permanganate (NaMnO4), was performed at the US Marine Corp Recruit Depot (MCRD), site 45 (Parris Island (PI), SC). The ground water was originally contaminated with perchloroethylene (PCE) (also known as tetrachloroethylene), a chlorinated solvent used in dry cleaner operations. High resolution site characterization involved multiple iterations of soil core sampling and analysis. Nested micro-wells and conventional wells were also used to sample and analyze ground water for PCE and decomposition products (i.e., trichloroethyelene (TCE), dichloroethylene (c-DCE, t-DCE), and vinyl chloride (VC)), collectively referred to as chlorinated volatile organic compounds (CVOC). This characterization methodology was used to develop and refine the conceptual site model and the ISCO design, not only by identifying CVOC contamination but also by eliminating uncontaminated portions of the aquifer from further ISCO consideration. Direct-push injection was selected as the main method of NaMnO4 delivery due to its flexibility and low initial capital cost. Site impediments to ISCO activities in the source area involved subsurface utilities, including a high pressure water main, a high voltage power line, a communication line, and sanitary and stormwater sewer lines. Utility markings were used in conjunction with careful planning and judicious selection of injection locations. A

  15. A subsurface add-on for standard atomic force microscopes.

    PubMed

    Verbiest, G J; van der Zalm, D J; Oosterkamp, T H; Rost, M J

    2015-03-01

    The application of ultrasound in an Atomic Force Microscope (AFM) gives access to subsurface information. However, no commercially AFM exists that is equipped with this technique. The main problems are the electronic crosstalk in the AFM setup and the insufficiently strong excitation of the cantilever at ultrasonic (MHz) frequencies. In this paper, we describe the development of an add-on that provides a solution to these problems by using a special piezo element with a lowest resonance frequency of 2.5 MHz and by separating the electronic connection for this high frequency piezo element from all other connections. In this sense, we support researches with the possibility to perform subsurface measurements with their existing AFMs and hopefully pave also the way for the development of a commercial AFM that is capable of imaging subsurface features with nanometer resolution.

  16. Debates - Stochastic subsurface hydrology from theory to practice: Introduction

    NASA Astrophysics Data System (ADS)

    Rajaram, Harihar

    2016-12-01

    This paper introduces the papers in the "Debates - Stochastic Subsurface Hydrology from Theory to Practice" series. Beginning in the 1970s, the field of stochastic subsurface hydrology has been an active field of research, with over 3500 journal publications, of which over 850 have appeared in Water Resources Research. We are fortunate to have insightful contributions from four groups of distinguished authors who discuss the reasons why the advanced research framework established in stochastic subsurface hydrology has not impacted the practice of groundwater flow and transport modeling and design significantly. There is reasonable consensus that a community effort aimed at developing "toolboxes" for applications of stochastic methods will make them more accessible and encourage practical applications.

  17. Preliminary Results of Lightning Based Subsurface Conductivity Imaging

    NASA Astrophysics Data System (ADS)

    Strauss, D.; Linscott, I.; Inan, U. S.

    2009-12-01

    Manmade sources in the VLF frequency band have been successfully employed in controlled source electromagnetic methods since the 1970's. We demonstrate that natural sources primarily from lightning at these frequencies offer a comparable and promising source for subsurface geophysical imaging. Radio atmospherics, commonly known as 'sferics,' are an abundant source of broadband (1-30kHz), impulsive signals for probing the surface of the earth. We show that simultaneous measurement of three orthogonal components of the time-varying magnetic field using a network of Stanford-developed ELF/VLF receivers provides a promising dataset for specifying subsurface material properties. Conductive anomalies in the subsurface have been observed to produce anomalous magnetic field response that fits in a perturbation model of the Earth-Ionosphere waveguide model of propagation at VLF frequencies. We present here the initial findings of the simultaneous collection of thousands of sferics in three distinct geologic settings in Western Nevada, Kansas, and Idaho.

  18. An Improved ERT Approach for the Investigation of Subsurface Structures

    NASA Astrophysics Data System (ADS)

    Lu, De-Bao; Wang, Feng; Chen, Xiao-Dong; Ou, Jian; Wang, Hui

    2017-01-01

    The joint use of multiple geophysical data types has been proven to be a powerful tool to both improve subsurface imaging and help in the interpretation process. The main goal of this paper is to develop a multi-geophysical approach for subsurface experimental investigations in which seismic data are used to improve electrical resistivity tomography quality. The basic philosophy of the method is that seismic travel time data will be used to construct the prior model for the resistivity inversion. Synthetic data were employed to demonstrate the improvements enabled by the use of this strategy. Afterwards, the scheme was applied successfully on field data from northwestern China. The outcomes reveal that the multi-geophysical approach improves the interpretation of the subsurface over a single source.

  19. Correct use of cone penetrometer sensors to predict subsurface conditions

    SciTech Connect

    Walker, J.L.; Rose, C.M.; Armstrong, S.C.; Burton, J.C.

    1997-09-01

    When cone penetrometer testing (CPT) technology is used with in-situ sensors and probes to characterize subsurface conditions in environmental investigations, each sensor must be calibrated with high quality, site specific data to establish essential interpretation criteria. Mechanical, geophysical, and chemical sensor data collected for a site in South Carolina without such controls were misleading. Core logs obtained subsequently had major lithologic discrepancies with the soil classification based on the CPT sensor data. In addition, detailed core sampling and laboratory analysis showed that the sensor data on chemical contaminants included false positive and false negative results. In contrast, for a site in Nebraska, CPT data calibrated with high quality site controls provided a detailed interpretation of subsurface conditions relevant to contaminant fate and transport. On the basis of the work in Nebraska, Argonne scientists are continuing to develop criteria to improve the interpretation of complex subsurface stratigraphy.

  20. The Mojave vadose zone: a subsurface biosphere analogue for Mars.

    PubMed

    Abbey, William; Salas, Everett; Bhartia, Rohit; Beegle, Luther W

    2013-07-01

    If life ever evolved on the surface of Mars, it is unlikely that it would still survive there today, but as Mars evolved from a wet planet to an arid one, the subsurface environment may have presented a refuge from increasingly hostile surface conditions. Since the last glacial maximum, the Mojave Desert has experienced a similar shift from a wet to a dry environment, giving us the opportunity to study here on Earth how subsurface ecosystems in an arid environment adapt to increasingly barren surface conditions. In this paper, we advocate studying the vadose zone ecosystem of the Mojave Desert as an analogue for possible subsurface biospheres on Mars. We also describe several examples of Mars-like terrain found in the Mojave region and discuss ecological insights that might be gained by a thorough examination of the vadose zone in these specific terrains. Examples described include distributary fans (deltas, alluvial fans, etc.), paleosols overlain by basaltic lava flows, and evaporite deposits.