NASA Astrophysics Data System (ADS)
León, Ricardo; Somoza, Luis; Medialdea, Teresa; Vázquez, Juan Tomás; González, Francisco Javier; López-González, Nieves; Casas, David; del Pilar Mata, María; del Fernández-Puga, María Carmen; Giménez-Moreno, Carmen Julia; Díaz-del-Río, Víctor
2012-12-01
During the MVSEIS-08 cruise of 2008, ten new mud volcanoes (MVs) were discovered on the offshore Moroccan continental margin (Gulf of Cádiz) at water depths between 750 and 1,600 m, using multibeam bathymetry, backscatter imagery, high-resolution seismic and gravity core data. Mud breccias were recovered in all cases, attesting to the nature of extrusion of these cones. The mud volcanoes are located in two fields: the MVSEIS, Moundforce, Pixie, Las Negras, Madrid, Guadix, Almanzor and El Cid MVs in the western Moroccan field, where mud volcanoes have long been suspected but to date not identified, and the Boabdil and Al Gacel MVs in the middle Moroccan field. Three main morphologies were observed: asymmetric, sub-circular and flat-topped cone-shaped types, this being the first report of asymmetric morphologies in the Gulf of Cádiz. Based on morpho-structural analysis, the features are interpreted to result from (1) repeated constructive (expulsion of fluid mud mixtures) and destructive (gravity-induced collapse and submarine landsliding) episodes and (2) interaction with bottom currents.
Dispersal of river sediment in the Southern California Bight
Warrick, J.A.; Farnsworth, K.L.
2009-01-01
The rivers of Southern California deliver episodic pulses of water, sediment, nutrients, and pollutants to the region's coastal waters. Although river-sediment dispersal is observed in positively buoyant (hypopycnal) turbid plumes extending tens of kilometers from river mouths, very little of the river sediment is found in these plumes. Rather, river sediment settles quickly from hypopycnal plumes to the seabed, where transport is controlled by bottom-boundary layer processes, presumably including fluid-mud (hyperpycnal) gravity currents. Here we investigate the geographical patterns of river-sediment dispersal processes by examining suspended-sediment concentrations and loads and the continental shelf morphology offshore river mouths. Throughout Southern California, river sediment is discharged at concentrations adequately high to induce enhanced sediment settling, including negative buoyancy. The rivers draining the Western Transverse Range produce suspended-sediment concentrations that are orders of magnitude greater than those in the urbanized region and Peninsular Range to the south, largely due to differences in sediment yield. The majority of sediment discharge from the Santa Clara River and Calleguas Creek occurs above the theoretical negative buoyancy concentration (>40 g/l). These rivers also produce event sediment loading as great as the Eel River, where fluid-mud gravity currents are observed. The continental shelf of Southern California has variable morphology, which influences the ability to transport via gravity currents. Over half of the rivers examined are adjacent to shelf slopes greater than 0.01, which are adequately steep to sustain auto-suspending gravity currents across the shelf, and have little (<10 m) Holocene sediment accumulation. Shelf settings of the Ventura, Santa Clara, and Tijuana Rivers are very broad and low sloped (less than 0.004), which suggests that fluid-mud gravity currents could transport across these shelves, albeit slowly (??10 cm/s) and only with adequate wave-generated shear stress and sediment loading. Calleguas Creek is unique in that it discharges directly into a steepsloped canyon (greater than 0.1) that should allow for violent auto-suspending gravity currents. In light of this, only one shelf setting-the Santa Clara and Ventura-has considerable Holocene sediment accumulation (exceeding 60 m), and here we show that the morphology of this shelf is very similar to an equilibrium shape predicted by gravity-current sediment transport. Thus, we conclude that a wide distribution of river-shelf settings occur in the Southern California Bight, which will directly influence sediment dispersal processes-both dilute suspended and gravity-current transport-and sediment-accumulation patterns. ?? 2009 The Geological Society of America.
Environmental Assessment for Selected Regions in the Mediterranean Sea
1992-01-01
derived from gravity and turbidity flows and include ash layers interbedded with hemipelagic mud. Sedimen- tation rates in these regions are on the order of...CURRENT METERS, ALBORAN I (PISTEK 1984)0& CURRENT METERS, ALBORAN III (PISTEK 1987) A DRIFTING CURRENT METERIS , ALBORAN 11 (PISTEK 1987) 0: CURRENT
NASA Astrophysics Data System (ADS)
Mullane, M.; Kumpf, L. L.; Kineke, G. C.
2017-12-01
The Huanghe (Yellow River), once known for extremely high suspended-sediment concentrations (SSCs) that could produce hyperpycnal plumes (10s of g/l), has experienced a dramatic reduction in sediment load following the construction of several reservoirs, namely the Xiaolangdi reservoir completed in 1999. Except for managed flushing events, SSC in the lower river is now on the order of 1 g/l or less. Adaptations of the Chezy equation for gravity-driven transport show that dominant parameters driving hyperpycnal underflows include concentration (and therefore density), thickness of a sediment-laden layer and bed slope. The objectives of this research were to assess the potential for gravity-driven underflows given modern conditions at the active river mouth. Multiple shore-normal transects were conducted during research cruises in mid-July of 2016 and 2017 using a Knudsen dual-frequency echosounder to collect bathymetric data and to document the potential presence of fluid mud layers. An instrumented profiling tripod equipped with a CTD, optical backscatterance sensor and in-situ pump system were used to sample water column parameters. SSCs were determined from near-bottom and surface water samples. Echosounder data were analyzed for bed slopes at the delta-front and differences in depth of return for the two frequencies (50 and 200 kHz), which could indicate fluid muds. Bathymetric data analysis yielded bed slope measurements near or above threshold values to produce gravity-driven underflows (0.46°). The maximum observed thickness of a potential fluid mud layer was 0.7 m, and the highest sampled near-bed SSCs were nearly 14 g/l for both field campaigns. These results indicate that the modern delta maintains potential for sediment gravity-driven underflows, even during ambient conditions prior to maximum summer discharge. These results will inform future work quantitatively comparing the contributions of all sediment dispersal mechanisms near the active Huanghe delta environment, including advection of the buoyant river plume and wave resuspension and transport by tidal currents.
Factors controlling mud accumulation in the Heuksan mud belt off southwestern Korea
NASA Astrophysics Data System (ADS)
Chang, Tae Soo; Ha, Hun Jun; Chun, Seung Soo
2015-12-01
The Heuksan mud belt (hereafter HMB) is 20~50 km wide, ~200 km long, and ~50 m thick, having accumulated in the course of the Holocene transgression on the tide-dominated epicontinental shelf southwest of Korea. The internal architecture of the HMB is characterized by offshore prograding clinoforms. Of particular interest are the depositional processes responsible for this anomalously thick mud accumulation within a relatively short period of time. Tidal currents are important in the dispersal of mud in the HMB, although these alone cannot explain such an enormous mud deposit. In order to understand the formative processes of the HMB, a detailed sedimentary facies analysis, including high-resolution grain-size measurements, has been conducted on more than 30 short cores and three long drill cores recovered from the mud belt. Five major mud facies were identified. Of these, mud sequences showing a thickening-thinning trend of alternating silt and clay laminae suggestive of a tidal origin occur dominantly at inner to mid shelf locations. By contrast, internally structureless muds with sharp bases and no bioturbation, which are interpreted of representing fluid-mud deposits, are widespread at mid to outer shelf locations. Wave-generated mud ripples and storm beds on the inner shelf suggest that storm waves in winter resuspend previously deposited mud to form near-bed fluid-mud suspensions with resulting gravity-driven mud transport across the low-gradient outer shelf. This previously not recognized process is probably a major factor controlling depositional processes on the giant mud belt, enabling rapid accumulation and offshore progradation even during transgression, i.e., at times of sea-level rise.
Geoacoustic Characterization of the Mud Drape at the New England Mud Patch
NASA Astrophysics Data System (ADS)
Reed, A. H.
2016-02-01
The New England Mud Patch is an extensive deposit of fine-grained sediments that extends from an area south of Cape Cod, MA to south of Montauk Point Long Island, NY out on the continental shelf in water depths of 60 to 90 meters. The mud patch has a remarkable accumulation of up to a 13 meter thick sequence of mud that overlays a transgressive surface of Pleistocene Age and then thins out on the periphery where surficial sediments convert from mud to sand and sand/gravel. The deposit likely accumulated in this region due to the coalescing of shelf currents that had oppositional flow. This work focuses on a section of the mud patch that is centered over the thickest portion of mud and extends east-west for 30 km and north south for 10 km. Gravity cores were collected throughout this region and the cores penetrated the upper 2-4 m of mud at 28 different sites with multiple cores collected in several locations. The mud thickness in these regions exceeded the core barrel length, therefore the cores did not penetrate into the basal sand sediment layer, a relict transgressional horizon, which displays prominently in the acoustic data for this selected region. These cores were evaluated for compressional sound speed (averaging 1480 m/s) and density (1580 kg/m3) and found to be largely homogeneous and similar throughout the study area. The largest source of inhomogeneity was due to dispersed shell hash and disarticulated bivalves, but these inclusions represent minor components in the total sediment volume. The overlying sediment that characterizes the New England Mud Patch can be readily classified as mud, silty mud, or sandy-silty mud. This fine-grained sediment deposit reflects upon the low-energy nature of the hydrodynamics within this region.
Rapid formation of hyperpycnal sediment gravity currents offshore of a semi-arid California river
Warrick, J.A.; Xu, Jie; Noble, M.A.; Lee, H.J.
2008-01-01
Observations of sediment dispersal from the Santa Clara River of southern California during two moderately sized river discharge events suggest that river sediment rapidly formed a negatively buoyant (hyperpycnal) bottom plume along the seabed within hours of peak discharge. An array of acoustic and optical sensors were placed at three stations 1 km from the Santa Clara River mouth in 10-m water depth during January-February 2004. These combined observations suggest that fluid mud concentrations of suspended sediment (>10 g/l) and across-shore gravity currents (???5 cm/s) were observed in the lower 20-40 cm of the water column 4-6 h after discharge events. Gravity currents were wave dominated, rather than auto-suspending, and appeared to consist of silt-to-clay sized sediment from the river. Sediment mass balances suggest that 25-50% of the discharged river sediment was transported by these hyperpycnal currents. Sediment settling purely by flocs (???1 mm/s) cannot explain the formation of the observed hyperpycnal plumes, therefore we suggest that some enhanced sediment settling from mixing, convective instabilities, or diverging plumes occurred that would explain the formation of the gravity currents. These combined results provide field evidence that high suspended-sediment concentrations from rivers (>1 g/l) may rapidly form hyperpycnal sediment gravity currents immediately offshore of river mouths, and these pathways can explain a significant portion of the river-margin sediment budget. The fate of this sediment will be strongly influenced by bathymetry, whereas the fate of the remaining sediment will be much more influenced by ocean currents.
Abdul Razak, Rafiza; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Hardjito, Djwantoro; Yahya, Zarina
2015-01-01
This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA) using LUSI (Sidoarjo mud) and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA) ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value) of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA) ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM) image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced. PMID:26006238
NASA Astrophysics Data System (ADS)
Chien, C. C.; Liu, J. T.; Yang, R.; Huh, C. A.; Su, C. C.
2016-02-01
Sediments in the Taiwan Strait are originated from Mainland China and Taiwan. The China Coastal Current, influenced by the northeast monsoon in winter, becomes enhanced, which caries the sediments exported from the Yangtze River to the southern East China Sea and the Taiwan Strait along the Zhemin-Taiwan Strait mud belt. The sediment transport process is also influenced by tidal current and Kuroshio Branch Current and Taiwan Warm Current, making the seafloor sediment signals complex. This study used R/V Ocean Researcher V (Cruise 0032), to collect six box cores and three gravity cores along the Zhemin mud belt and the mud belt in northern Taiwan Strait in the winter of 2014. From the core samples, grain-size distribution, Multi-Sensor Core Logger, and 7Be activity were measured to investigate the sedimentation process along the mud belts. The box core taken at the mouth of the Changjiang- is composed of homogeneous clay and rich in shell fragments. The core off the mouth of Ou River is composed of homogeneous clay, but showing horizontal laminations. Near the Taishan Island off the coast of Zhejiang the core is consisted of a homogeneous sandy sediments that turned into clay. Off the mouth of the Min River the core consists of clay with shell fragments. Off the coast of the Wu River on the west coast of the Taiwan, the core is mainly composed of muddy sediments, which has the siltstone layers of oblique bedding. Off the mouth of Zhuoshui River in central Taiwan, the core is composed of sandy sediments. From the mouth of the Changhjiang, Zhemin mud belt, the northern Taiwan Strait mud belt, to the central Taiwan Strait, 7Be activity in the seafloor sediment indicates that the freshness of the terrigenous sediments decreased. The Mass Magnetic Susceptiblity (MSI) demonstrates that the terrigenous sediments decreased from north to south. The MSI signals in the core off the mouth of the Minjiang are different from those in the neighboring cores. This is suspected due to the convergence of sediments from the Changjiang and Taiwan. The particle sizes of the cores show that the sediment became coarser from the north to south. In the future the study will make use of 210Pbex, and other environmental and provenance such as water dynamic mechanism variables to explore the sediment source and sink patterns along with the Zhemin-Taiwan Strait mud belts.
Environmental dust effects on aluminum surfaces in humid air ambient.
Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser
2017-04-05
Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems.
Environmental dust effects on aluminum surfaces in humid air ambient
Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser
2017-01-01
Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems. PMID:28378798
Investigating Deep-Marine Sediment Waves in the Northern Gulf of Mexico Using 3D Seismic Data
NASA Astrophysics Data System (ADS)
Wang, Z.; Gani, M. R.
2016-12-01
Deep-water depositional elements have been studied for decades using outcrop, flume tank, sidescan sonar, and seismic data. Even though they have been well recognized by researchers, the improvements in the quality of 3D seismic data with increasingly larger dimension allow detailed analysis of deep-water depositional elements with new insights. This study focuses on the deep-marine sediment waves in the northern Gulf of Mexico. By interpreting a 3D seismic dataset covering 635 km2 at Mississippi Canyon and Viosca Knoll areas, large sediment waves, generated by sediment gravity flows, were mapped and analyzed with various seismic attributes. A succession of sediment waves, approximately 100 m in thickness, is observed on the marine slope that tapers out at the toe of the slope. The individual sediment wave exhibits up to 500 m in wavelength and up to 20 m in height. The wave crests oriented northeast-southwest are broadly aligned parallel to the regional slope-strike, indicating their sediment gravity flow origin. The crestlines are straight or slightly sinuous, with sinuosity increasing downslope. Their anti-dune patterns likely imply the presence of supercritical flows. The sediment waves have a retrogradational stacking pattern. Seismic amplitude maps of each sediment wave revealed that after depositing the majority of sheet-like sands on the upper slope, sediment gravity flows started to form large sediment waves on the lower slope. The steep and narrow upcurrent flanks of the sediment waves always display higher amplitudes than the gentle and wide downcurrent flanks, indicating that the sands were likely preferentially trapped along the upcurrent flanks, whereas the muds spread along the downcurrent flanks. The formation of sediment waves likely requires a moderate sand-mud ratio, as suggested by these observations: (1) absence of sediment waves on the upper slope where the sands were mainly deposited as unconfined sheets with a high sand-mud ratio; (2) absence of sediment waves on the basin floor, which is covered mainly by muds and hemipelagic sediments with a low sand-mud ratio; and (3) presence of sediment waves on the lower slope with a moderate sand-mud ratio.
A study of iron mineral transformation to reduce red mud tailings.
Li, L Y
2001-01-01
This study examines the effects of iron mineral transformation in an aluminum extraction process on the settling behavior, and the physical and chemical properties of the resulting red mud slurry that must be disposed of. By producing a red mud with a higher solid content, the total volume of mud slurry will also be reduced for a given alumina production rate and more caustic soda will be recovered. The settling behavior and the mineralogical, physical, and physico-chemical properties of one bauxite and three red muds processed under varying conditions were analyzed based on examination of the iron mineral transformations. The properties of red muds derived from the same bauxite can differ markedly due to variations in operating conditions of the Bayer process, such as temperature and the addition of a reducing agent. The settling of red mud can be improved by converting goethite into hematite and/or magnetite to produce a mud of larger particle size, smaller specific surface area, and larger specific gravity, characteristics which reduce the total volume of mud slurry to be disposed of and which allow for less potential contamination from caustic soda. This study also found that the by-product--Bayer sodalite--has the high exchange capacity for Na+ that might contribute to the long-term environmental problems.
Cenozoic seismic stratigraphy of the SW Bermuda Rise
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mountain, G.S.; Driscoll, N.W.; Miller, K.G.
1985-01-01
The seismic Horizon A-Complex (Tucholke, 1979) readily explains reflector patterns observed along the western third of the Bermuda Rise; farther east, basement is much more rugged and gravity flows shed from local topographic highs complicate the stratigraphy. Distal turbidites on the southwestern Bermuda Rise onlap reflector A* from the west, suggesting early Paleocene mass wasting of the North American margin. Locally erosive bottom currents cut into the middle Eocene section of the SW Bermuda Rise; these northward flowing currents preceded those that formed reflector Au along the North American margin near the Eocene-Oligocene boundary. Southward flowing currents swift enough tomore » erode the sea floor and to form reflector Au did not reach as far east as the SW Bermuda Rise. Instead, the main effect of these Au currents was to pirate sediment into contour-following geostrophic flows along the North American margin and to deprive the deep basin and the Bermuda Rise of sediment transported down-slope. Consequently, post-Eocene sediments away from the margin are fine-grained muds. Deposition of these muds on the SW Bermuda Rise was controlled by northward flowing bottom currents. The modern Hatteras Abyssal Plain developed in the late Neogene as turbidites once again onlapped the SW Bermuda Rise. Today, these deposits extend farthest east in fracture zone valleys and in the swales between sediment waves. Northward flowing currents continue at present to affect sediment distribution patterns along the western edge of the Bermuda Rise.« less
NASA Astrophysics Data System (ADS)
Fan, Aiping; Yang, Renchao; (Tom) van Loon, A. J.; Yin, Wei; Han, Zuozhen; Zavala, Carlos
2018-08-01
The ongoing exploration for shale oil and gas has focused sedimentological research on the transport and deposition mechanisms of fine-grained sediments, and more specifically on fine-grained mass-flow deposits. It appears, however, that no easily applicable classification scheme for gravity-flow deposits exists, and that such classifications almost exclusively deal with sandy and coarser sediments. Since the lack of a good classification system for fine-grained gravity flow deposits hampers scientific communication and understanding, we propose a classification scheme on the basis of the mud content in combination with the presumed transport mechanism. This results in twelve types of gravity-flow deposits. In order to show the practical applicability of this classification system, we apply it to the Triassic lacustrine Yanchang Formation in the southern Ordos Basin (China), which contains numerous slumps, debris-flows deposits, turbidites and hyperpycnites. The slumps and debrites occur mostly close to a delta front, and the turbidites and hyperpycnites extend over large areas from the delta slopes into the basin plain. The case study shows that (1) mud cannot only be transported but also deposited under active hydrodynamic conditions; (2) fine-grained gravity-flow constitute a significant part of the lacustrine mudstones and shales; (3) muddy gravity flows are important for the transport and deposition of clastic particles, clay minerals and organic matter, and thus are important mechanisms involved in the generation of hydrocarbons, also largely determining the reservoir capability for unconventional petroleum.
NASA Astrophysics Data System (ADS)
Hsu, H. H.; Chen, T. T.; Liu, C. S.; Su, C. C.; Paull, C. K.; Caress, D. W.; Gwiazda, R.; Chen, Y. H.
2017-12-01
Mud Volcano V (MV5) is an active submarine mud volcano sitting on top of a mud diapir ridge at water depths of 600 m in the active margin offshore of southwestern Taiwan. This cone-shape mud volcano is almost 3-km-wide, 200-m-high, with 9.5° slopes, and explosively ejects streams of mud every 1.5-3 minutes. It was first mapped in 2013 with MBARI's mapping AUV (autonomous underwater vehicle). In 2017, a repeated AUV mapping survey was conducted to see if significant bathymetric changes took place since 2013, and to investigate the fluxes of fluids that pass through diapiric structures in an active continental margin. In addition to high-resolution bathymetry (1-m-resolution), sub-bottom profiling and side-scan sonar data acquired by the AUV, and videos and samples collected by MBARI's miniROV, we also incorporate multichannel seismic reflection data and gravity core sample analyses in this study. AUV bathymetry data reveal that there are two gryphons on the eastern slope of MV5. In the 2017 survey the mapped sizes of the two side cones were 80 m wide, 35 m long, 20 m relief and 40 m wide, 40 m long, 12 m relief, respectively. Comparing the bathymetry mapped in the 2017 AUV survey with that surveyed in 2013, no obvious overall morphological changes in MV5 are detected, except around the two gryphons. In the time period between the surveys, due to venting of mud from the two gryphons, two series of flow deposits which can be up to 5 meters thick are observed along the slope in the east side of both gryphons. The center depressions of these two gryphons have increased by 1-5 meters depth in their west side. Seismic and sub-bottom profiles reveal amplitude anomalies in the sub-strata of MV5 which indicate possible fluid migration paths of mud flows from deep. The trace of mud flow from the top of MV5 to its foot can be delineated from the side-scan sonar images. On the basis of 210Pbex chronology dating method, the sedimentation rate on the surface of MV5 is very slow (0.057 cm/y). High methane anomalies are discovered on MV5 based on the geochemical analysis results of gravity core samples, but the heat probe did not detect obvious temperature changes before and after venting episodes in the 2017 survey. Based on this comprehensive study, a three-step model is proposed to explain mud volcano venting processes in the active margin offshore of SW Taiwan.
Comparison with Offshore and Onshore Mud Volcanoes in the Southwestern Taiwan
NASA Astrophysics Data System (ADS)
Chen, Y. H.; Su, C. C.; Chen, T. T.; Liu, C. S.; Paull, C. K.; Caress, D. W.; Gwiazda, R.; Lundsten, E. M.; Hsu, H. H.
2017-12-01
The offshore area southwest (SW) of Taiwan is on the convergent boundary between the Eurasian and Philippine Sea plates. The plate convergence manifests in this unique geological setting as a fold-and-thrust-belt. Multi-channel seismic profiles, and bathymetry and gravity anomaly data collected from Taiwan offshore to the SW show the presence of a large amount of mud volcanoes and diapirs with NE-SW orientations. In the absence of comprehensive sampling and detailed geochemistry data from submarine mud volcanoes, the relation between onshore and offshore mud volcanoes remains ambiguous. During two MBARI and IONTU joint cruises conducted in 2017 we collected high-resolution multibeam bathymetry data (1-m-resolution) and chirp sub-bottom profiles with an autonomous underwater vehicle (AUV) from submarine Mud Volcano III (MV3), and obtained precisely located samples and video observations with a remotely operated vehicle (ROV). MV3 is an active submarine mud volcano at 465 m water depth offshore SW Taiwan. This cone-shape mud volcano is almost 780 m wide, 150 m high, with 8° slopes, and a 30 m wide mound on the top. Several linear features are observed in the southwest of the mound, and these features are interpreted as a series of marks caused by rolling rocks that erupted from the top of MV3. We collected three rocks and push cores from MV3 and its top with the ROV, in order to compare their chemical and mineralogical composition to that of samples collected from mud volcanoes along the Chishan fault. The surface and X-radiography imaging, 210Pb chronology, grain size and X-ray diffractometer analyses were conducted to compare geochemical and sedimentary properties of offshore and onshore mud volcanoes. The results indicate that the offshore and onshore mud volcanoes have similar characteristics. We suggest that offshore and onshore mud volcanoes of SW Taiwan are no different in the source of their materials and their mechanism of creation and evolution.
NASA Astrophysics Data System (ADS)
Tan, Mingxuan; Zhu, Xiaomin; Geng, Mingyang; Zhu, Shifa; Liu, Wei
2017-10-01
Bed variability of sediment-gravity-flow deposits is quite prevalent in deep-marine settings, but it has not been well investigated in lacustrine settings. The depositional characteristics of various event beds are characterized in the North Slope Belt of the Bongor Basin (Chad), using detailed sedimentological, petrographic, geochemical as well as palynological analysis. Four bed types including classical turbidite bed, debrite bed, hybrid event bed, and hyperpycnite bed were distinguished based on their interpreted depositional processes. Variable mud contents of debrite beds and classic turbidite beds show distinct genetic characteristics in four core wells, whilst the high mud content of cohesive debrite interval and the low mud content of turbidite interval in hybrid event bed demonstrate the existence of flow transformation. Generally, several trace element and rare earth element proxy parameters show that these gravity-flow deposits of BS1-1 and D-3 cores are formed in more distal depositional settings than them of BN8 and BNE3 cores, which is also well consistent with sedimentological understandings achieved by seismic facies analysis. Although palynological results show a general hot arid climate during the deposition of the Prosopis Formation, but the climate-sensitive Sr/Cu ratio demonstrates that most sampled turbidite beds are postulated to be formed within a short humid pulse. The multi-approach analysis has illustrated that two potential forming mechanisms (delta-front-failure and flood-related origin) can be derived in different cored wells of such a small lacustrine rift basin. Differentiated flow transformation plays a significant role in the depositional characteristics and heterogenetic distribution of these event deposits.
Gas hydrates and active mud volcanism on the South Shetland continental margin, Antarctic Peninsula
NASA Astrophysics Data System (ADS)
Tinivella, U.; Accaino, F.; Della Vedova, B.
2008-04-01
During the Antarctic summer of 2003 2004, new geophysical data were acquired from aboard the R/V OGS Explora in the BSR-rich area discovered in 1996 1997 along the South Shetland continental margin off the Antarctic Peninsula. The objective of the research program, supported by the Italian National Antarctic Program (PNRA), was to verify the existence of a potential gas hydrate reservoir and to reconstruct the tectonic setting of the margin, which probably controls the extent and character of the diffused and discontinuous bottom simulating reflections. The new dataset, i.e. multibeam bathymetry, seismic profiles (airgun and chirp), and two gravity cores analysed by computer-aided tomography as well as for gas composition and content, clearly shows active mud volcanism sustained by hydrocarbon venting in the region: several vents, located mainly close to mud volcanoes, were imaged during the cruise and their occurrence identified in the sediment samples. Mud volcanoes, vents and recent slides border the gas hydrate reservoir discovered in 1996 1997. The cores are composed of stiff silty mud. In core GC01, collected in the proximity of a mud volcano ridge, the following gases were identified (maximum contents in brackets): methane (46 μg/kg), pentane (45), ethane (35), propane (34), hexane (29) and butane (28). In core GC02, collected on the flank of the Vualt mud volcano, the corresponding data are methane (0 μg/kg), pentane (45), ethane (22), propane (0), hexane (27) and butane (25).
Hidden values in bauxite residue (red mud): Recovery of metals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Yanju; Naidu, Ravi, E-mail: ravi.naidu@unisa.edu.au
Highlights: • Current iron recovery techniques using red mud are depicted. • Advantages and disadvantages exist in different recovering processes. • Economic and environmental friendly integrated usage of red mud is promising. - Abstract: Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially.more » Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud.« less
NASA Astrophysics Data System (ADS)
Johnson, K. E.; Marsaglia, K. M.
2015-12-01
The Izu-Bonin-Mariana (IBM) Arc System, south of Japan, hosts a multitude of active and extinct (remnant) arc volcanic sediment sources. Core extracted adjacent to the proto-IBM arc (Kyushu-Palau Ridge; KPR) in the Amami-Sankaku Basin on International Ocean Discovery Program (IODP) Expedition 351 contains evidence of the variety of sediment sources that have existed in the area as a result of changing tectonic regimes through arc development, backarc basin formation and remnant arc abandonment. Approximately 1000 meters of Eocene to Oligocene volcaniclastic sedimentary rocks were analyzed via shipboard core photos, core descriptions, and thin sections with the intention of understanding the depositional history at this site. These materials contain a crucial record of arc development complementary to the Neogene history preserved in the active reararc (Expedition 350) and compressed whole-arc record in the current forearc (Expedition 352). A database of stratigraphic columns was created to display grain size trends, facies changes, and bedding characteristics. Individual beds (depositional events) were classified using existing and slightly modified classification schemes for muddy, sandy and gravel-rich gravity flow deposits, as well as muddy debris flows and tuffs. Utilizing the deep marine facies classes presented by Pickering et al. (1986), up section changes are apparent. Through time, as the arc developed, facies and bedding types and their proportions change dramatically and relatively abruptly. Following arc initiation facies are primarily mud-rich with intercalated tuffaceous sand. In younger intervals, sand to gravel gravity-flow deposits dominate, becoming more mud-rich. Muddy gravity flow deposits, however, dominate farther upsection. The overall coarsening-upward pattern (Unit III) is consistent with building of the arc edifice. Farther upsection (Unit II) an abrupt fining-upward trend represents the onset of isolation of the KPR as backarc spreading in the Shikoku Basin was initiated. This information will be combined with volcanic provenance and geochemical information from other studies, ultimately creating a deep-marine facies model for intraoceanic arc systems.
Modern Estuarine Sedimentation in Suisun Bay, California
NASA Astrophysics Data System (ADS)
Chin, J. L.; Orzech, K.; Anima, R. J.; Jaffe, B.
2002-12-01
Suisun Bay is the northeasternmost part of San Francisco Bay (California), the largest estuary on the Pacific Coast of the United States. Suisun Bay's geographic and morphologic position are unique in that it occupies the head of the estuary and is subject to the maximum freshwater inflow and sediment input of the Sacramento-San Joaquin Rivers, whose drainage basin covers 40% of the land area of California. Suisun Bay consists of two smaller subembayments, Grizzly and Honker Bays. Gravity cores obtained in 1990-1991 and 1999 were analyzed to delineate depositional environments and sedimentation patterns in Suisun Bay. Major depositional environments include: tidal channel (subtidal), tidal channel banks (subtidal), tidal flat (intertidal to subtidal), and bay mouth (subtidal). The tidal channel environment includes both large and small channels in Suisun Bay as well as the tidal sloughs Suisun and Montezuma Sloughs. The coarsest sediment, usually sand or muddy sand, characterize this environment and water depths range from 2 to 11 m. Thin (1-2 mm) and discontinuous silt and clay laminae are common. Suisun and Montezuma Sloughs are the exception to this pattern in that they consist of massive, intensely bioturbated muds. Tidal channel banks (both "cut" and "accretionary" channel margins), particularly accretionary banks, are characterized by low-to-moderate bioturbation and sandy mud to muddy sand lithology. Typically alternating sand and mud beds (1-6 cm thick) are present; both types of beds consist of 1mm to 1cm thick subhorizontal to inclined laminae. Laminae composed of organic detritus are also present. Where this environment is transitional with the tidal flat environment water depths range from 2-8 m. Tidal flat environments include the "sand" shoals present on bathymetry charts, and are typically a bioturbated muddy sand to sandy mud. Sand and mud beds, 1-3 cm thick, are often characterized by very fine 1-2 mm thick silt and mud laminae. Water depths range from 2 to 4.5 m where these laminated tidal flat sediments occur. Bay mouth environments occur only in the distal portions of Grizzly and Honker Bays, subembayments of Suisun Bay proper. This environment is transitional with both tidal channel bank and tidal flat environments and shares characteristics with each. Massive to interbedded mud is the most common lithology, although sandy mud to muddy sand also occurs. Centimeters thick sand and mud beds typically alternate vertically. Bioturbation is low to moderate. Water depths over this environment range from 2 to 3 m. Depositional environments present in Suisun Bay are the result of a full range of tidal and fluvial processes as shown by the lithologies and alternating sediment stratigraphic patterns observed in cores. Very thin beds and intense bioturbation evidence intervals of very slow to negligible sedimentation. Rapid deposition and/or resuspension are evidenced by thick sediment intervals and by laminae that are continuous and apparently unbioturbated. Very fine scale sedimentation that may represent individual ebb and flood events as well as longer term seasonal sedimentation patterns are also present. An additional observation is that almost a quarter of the gravity cores reveal that modern estuarine deposits overlie an erosional surface that separate them from an organic-rich mud. This organic-rich mud, in one core to date, has been radiocarbon dated at roughly 4500 yrs. B.P. (J.Chin and K. Orzech, 2002, unpublished data). The organic-rich mud is interpreted as a tidal marsh deposit that pre-dates the present tidal marshes occurring in Suisun Bay.
NASA Astrophysics Data System (ADS)
Asada, M.
2017-12-01
Mud volcanoes (MV) are geological features that are observed all over the world, especially along plate convergent margins. MVs bring fluid and sediment to the surface from depth. MVs around Japan are expected to transport of information from the shallow portions of the seismogenic zone. The Kumano forearc basin (FAB) in the Nankai region is the most studied area in Japan. It is bounded by a shelf on the north, and the Kumano Basin edge fault zone (KBEFZ) on the south. The Kumano FAB has 1-2 km of sediment and overlies the accretionary prism. There are at least 14 MVs in the Kumano Basin. Most of them are found over the northern basin floor, and at least one MV is at the KBEFZ. The MV at the KBEFZ is imaged on a 3D seismic data set as a small topographic feature on seafloor with a disrupted BSR below it. On high-resolution acoustic imagery, it is an 80 100m-high hill with a crater-like depression. It is characterized by a negative ph anomaly detected just above it. High-backscatter seafloor recognized around the MV suggests that harder seafloor exists in that area. To determine whether large subseafloor diapirs exist below active MVs, we try to detect the gravity contrast between the allochthonous materials and basin sediment. Gravity data were collected by research vessels over the area in 2012 2017. After corrections of drift and Etovos effects, absolute gravity, free-air and Bouguer gravity anomalies were calculated. The gravity data do not always show anomalies directly on MVs over the northern basin, thus suggesting that larger diapirs which have gravity contrast over a few milli-Gals do not exist below most of MVs in this basin. Instead, a large negative gravity anomaly is found at the northeastern end of the Kumano Basin. Localized positive anomalies exist along the KBEFZ in the area of theMV. The positive anomaly may suggest that an allochthonous high-density sediment body intrudes along the highly deformed, weak, fault zone.
NASA Astrophysics Data System (ADS)
Carvalho, Lina; Monteiro, Rui; Figueira, Paula; Mieiro, Cláudia; Almeida, Joana; Pereira, Eduarda; Magalhães, Vítor; Pinheiro, Luís; Vale, Carlos
2018-01-01
Mud volcanoes are feature of the coastal margins where anaerobic oxidation of methane triggers geochemical signals. Elemental composition, percentage of fine particles and loss on ignition were determined in sediment layers of eleven gravity cores retrieved from four mud volcanoes (Sagres, Bonjardim, Soloviev and Porto) and three undefined structures located on the deep Portuguese margin of the Gulf of Cadiz. Calcium was positively correlated to Sr and inversely to Al as well as to most of the trace elements. Vertical profiles of Ba, Cd and As concentrations, and their ratios to Al, in Porto and Soloviev showed pronounced enhancements in the top 50-cm depth. Sub-surface enhancements were less pronounced in other mud volcanoes and were absent in sediments from the structures. These profiles were interpreted as diagenetic enrichments related to the anaerobic oxidation of methane originated from upward methane-rich fluxes. The observed barium fronts were most likely caused by the presence of barite which precipitated at the sulphate-methane transition zone. Cd and As enrichments have probably resulted from successive dissolution/precipitation of sulphides in response to vertical shifts of redox boundaries.
Hidden values in bauxite residue (red mud): recovery of metals.
Liu, Yanju; Naidu, Ravi
2014-12-01
Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Nurhandoko, Bagus Endar B.
2015-09-01
Extraordinary mudflow has happened in Sidoarjo, East Java, Indonesia since 2006. This mud comes from the giant crater that is located close to the BJP - 01. Thousands of homes have been submerged due to mudflow. Till today this giant mud crater is still has great strength despite the mud flowing over 8 years. This is a very rare phenomenon in the world. This mud flow mechanism raises big questions, because it has been going on for years, naturally the mudflow will stop by itself because the pressure should be reduced. This research evaluates all aspects of integrated observations, laboratory tests and field observations since the beginning of this ongoing mudflow. Laboratory tests were done by providing hot air bubbles into the fluid inside the inverted funnel showed that the fluid can flow with a high altitude. It is due to the mechanism of buoyant force from air bubbles to the water where the contrast density of the water and the air is quite large. Quantity of air bubbles provides direct effect to the debit of fluid flow. Direct observation in the field, in 2006 and 2007, with TIMNAS and LPPM ITB showed the large number of air bubbles on the surface of the mud craters. Temperature observation on the surface of mud crater is around 98 degree C whereas at greater depth shows the temperature is increasingly rising. This strengthens the hypothesis or proves that the mud pumping mechanism comes from buoyant force of hot air bubbles. Inversion gravity images show that the deep subsurface of main crater is close to volcanic layers or root of Arjuna mountain. Based on the simulation laboratory and field observation data, it can be concluded that the geothermal factor plays a key role in the mudflow mechanism.
NASA Astrophysics Data System (ADS)
Alcántara-Carrió, Javier; Sasaki, Dalton Kei; Mahiques, Michel Michaelovitch de; Taborda, Rui; de Souza, Luiz Antonio Pereira
2017-10-01
The São Sebastião Channel (SSC), which separates São Sebastião Island from the continent, is a deep elongated strait on the inner shelf of the São Paulo Bight (SE Brazil). The aim of this study is to explain why it is presently sediment starved, instead of forming a tombolo. Wave data were obtained from both a WW3 model database and buoy records, and wave propagation patterns from the SWAN numerical model. Grain size trend analysis of 579 surficial sediment samples from the strait and the surrounding region served to estimate the residual transport directions. Bedload sediment transport was computed considering in situ currents and bottom sediment grain size. Moreover, six seismic profiles and one gravity core were obtained in the strait in order to evaluate the hickness of the sedimentary deposits. The geometry of the SSC (X/B=0.3, where B is the breakwater or island diameter and X is its cross-shore distance to the mainland) predicts that a tombolo should be formed, and wave patterns confirm that it is a zone sheltered from both S and NE waves. Previous studies have shown that the hydrodynamics of the SSC is controlled by wind-driven currents, which are more intense in the eastern and central sectors of the strait. The western sector is currently covered by sandy mud, whereas very coarse to fine sand prevails in the deeper eastern sector. Sediment patterns show a trend to deposition of fine sediment in the western sector of the SSC and two main depocentres located at the northern limit of the study area and at the southern mouth of the strait. Sandy mud in the western sector forms a 40-m-thick deposit close to the outer limit of Araçá Bay, whereas the remainder of the SSC is covered by a very thin layer of sandy sediments. Dominance of mud in the depositional western sector suggests low availability of sand in the area. Therefore, despite the geometry and wave patterns of the SSC favouring the formation of a tombolo, the dominance of wind-driven currents and the low availability of sand determine that such a sedimentary feature cannot be formed, resulting in a deep strait.
Continuous multi-component geophysical experiment on LUSI mud edifice: What can we learn from it?
NASA Astrophysics Data System (ADS)
Mauri, Guillaume; Husein, Alwi; Karyono, Karyono; Hadi, Soffian; Mazzini, Adriano; Collignon, Marine; Faubert, Maïté; Miller, Stephen A.; Lupi, Matteo
2016-04-01
The Lusi eruption is located in East Java, Indonesia, and is ongoing since May 29th, 2006. In the framework of joined international projects, several joint geophysical studies focussing on seismic monitoring, spatial investigation over the mud edifice and its surroundings are being conducted. Here we present freshly acquired data from a test site to investigate: (1) potential change in the natural electrical self-potential generation over time (2) potential change in gravity field associated to change in mass or volume, (3) if the geysering activity generates disruption on either the electrical or gravity field. We selected a location ˜200m to the NE of the active Lusi crater. The experiment site covers an area of 60m x 80m, crossing the boundaries between the soft and the solid walkable mud. The western edge of the study area was less than 100m away from the rim of the crater site. A self-potential array made of 6 Pb-PbCl2 electrodes was deployed over the site. The electrodes were positioned inside active seeps, on dry unaltered zones and close to the mud stream that flushes the water erupted from the crater site. All the electrodes were connected to a single Pb-PbCl2 electrode reference. A second array of 7 thermometers was installed positioning 5 of them next to SP electrodes, one to measure atmospheric temperature and another P/T probe to monitor the stream water. In addition a seismometer coupled with a HD video camera, a thermal camera and a gravimeter recorded on site for several days monitoring visual and seismic activity of the crater. The collected data allows us to 1) monitor and define the different geysering activities ongoing at the crater, 2) define the delay existing between the recorded seismicity and the visual observations, 3) verify if the crater activity triggers perturbations that are transmitted to e.g. the thousands of satellite seeps distributed in the 7 square kilometers zone inside the embankment; 4) how significant is the delay between the crater activity and the water streamed out.
Mud volcanoes of the Orinoco Delta, Eastern Venezuela
Aslan, A.; Warne, A.G.; White, W.A.; Guevara, E.H.; Smyth, R.C.; Raney, J.A.; Gibeaut, J.C.
2001-01-01
Mud volcanoes along the northwest margin of the Orinoco Delta are part of a regional belt of soft sediment deformation and diapirism that formed in response to rapid foredeep sedimentation and subsequent tectonic compression along the Caribbean-South American plate boundary. Field studies of five mud volcanoes show that such structures consist of a central mound covered by active and inactive vents. Inactive vents and mud flows are densely vegetated, whereas active vents are sparsely vegetated. Four out of the five mud volcanoes studied are currently active. Orinoco mud flows consist of mud and clayey silt matrix surrounding lithic clasts of varying composition. Preliminary analysis suggests that the mud volcano sediment is derived from underlying Miocene and Pliocene strata. Hydrocarbon seeps are associated with several of the active mud volcanoes. Orinoco mud volcanoes overlie the crest of a mud-diapir-cored anticline located along the axis of the Eastern Venezuelan Basin. Faulting along the flank of the Pedernales mud volcano suggests that fluidized sediment and hydrocarbons migrate to the surface along faults produced by tensional stresses along the crest of the anticline. Orinoco mud volcanoes highlight the proximity of this major delta to an active plate margin and the importance of tectonic influences on its development. Evaluation of the Orinoco Delta mud volcanoes and those elsewhere indicates that these features are important indicators of compressional tectonism along deformation fronts of plate margins. ?? 2001 Elsevier Science B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Yang, Xiaochen; Zhang, Qinghe; Hao, Linnan
2015-03-01
A water-fluid mud coupling model is developed based on the unstructured grid finite volume coastal ocean model (FVCOM) to investigate the fluid mud motion. The hydrodynamics and sediment transport of the overlying water column are solved using the original three-dimensional ocean model. A horizontal two-dimensional fluid mud model is integrated into the FVCOM model to simulate the underlying fluid mud flow. The fluid mud interacts with the water column through the sediment flux, current, and shear stress. The friction factor between the fluid mud and the bed, which is traditionally determined empirically, is derived with the assumption that the vertical distribution of shear stress below the yield surface of fluid mud is identical to that of uniform laminar flow of Newtonian fluid in the open channel. The model is validated by experimental data and reasonable agreement is found. Compared with numerical cases with fixed friction factors, the results simulated with the derived friction factor exhibit the best agreement with the experiment, which demonstrates the necessity of the derivation of the friction factor.
Model of modern dynamic deposition in the east China Sea
NASA Astrophysics Data System (ADS)
Zhou, Fugen
1989-09-01
Since the last rising of sea level, two branches of the Kuroshio, the Huanghai (Yellow Sea) coastal current (HCC; mainly cold water mass) and the Changjiang River outflow have controlled the modern dynamic deposition in the East China Sea. There are three depositing areas on the sea-bed under the above currents: a relict sand area un der the Taiwan Warm Current and the Huanghai Warm Current at the south-eastern area, the about 60 km2 round mud bank under the Huanghai Coastal Current at the northern area and the large subaqueous delta of mainly fine sand and silt under the Changjiang discharge flow in its estuary and the large narrow mud bank under the Zhejiang-Fujian Coastal Current, another round mud bank under the Changjiang discharge flow off Hangzhou Bay. The relict sand area has a coarsesand block under the Taiwan Warm Current bypassing Taiwan at the northern part of the island. The two round mud banks were formed in relatively static states by an anticlockwise converging cyclonic eddy. The coarsesand block was formed by a clockwise diverging cyclonic eddy. This new dynamic deposition theory can be used to explain not only the dynamic deposition process of clay, but also the patchy distribution of sediments on the shelves of the world ocean s.
Red mud as a carbon sink: variability, affecting factors and environmental significance.
Si, Chunhua; Ma, Yingqun; Lin, Chuxia
2013-01-15
The capacity of red mud to sequester CO(2) varied markedly due to differences in bauxite type, processing and disposal methods. Calcium carbonates were the dominant mineral phases responsible for the carbon sequestration in the investigated red mud types. The carbon sequestration capacity of red mud was not fully exploited due to shortages of soluble divalent cations for formation of stable carbonate minerals. Titanate and silicate ions were the two major oxyanions that appeared to strongly compete with carbonate ions for the available soluble Ca. Supply of additional soluble Ca and Mg could be a viable pathway for maximizing carbon sequestration in red mud and simultaneously reducing the causticity of red mud. It is roughly estimated that over 100 million tonnes of CO(2) have been unintentionally sequestered in red mud around the world to date through the natural weathering of historically produced red mud. Based on the current production rate of red mud, it is likely that some 6 million tonnes of CO(2) will be sequestered annually through atmospheric carbonation. If appropriate technologies are in place for incorporating binding cations into red mud, approximately 6 million tonnes of additional CO(2) can be captured and stored in the red mud while the hazardousness of red mud is simultaneously reduced. Copyright © 2012 Elsevier B.V. All rights reserved.
Large historical eruptions at subaerial mud volcanoes, Italy
NASA Astrophysics Data System (ADS)
Manga, M.; Bonini, M.
2012-11-01
Active mud volcanoes in the northern Apennines, Italy, currently have gentle eruptions. There are, however, historical accounts of violent eruptions and outbursts. Evidence for large past eruptions is also recorded by large decimeter rock clasts preserved in erupted mud. We measured the rheological properties of mud currently being erupted in order to evaluate the conditions needed to transport such large clasts to the surface. The mud is well-characterized by the Herschel-Bulkley model, with yield stresses between 4 and 8 Pa. Yield stresses of this magnitude can support the weight of particles with diameters up to several mm. At present, particles larger than this size are not being carried to the surface. The transport of larger clasts to the surface requires ascent speeds greater than their settling speed in the mud. We use a model for the settling of particles and rheological parameters from laboratory measurements to show that the eruption of large clasts requires ascent velocities > 1 m s-1, at least three orders of magnitude greater than during the present, comparatively quiescent, activity. After regional earthquakes on 20 May and 29 May 2012, discharge also increased at locations where the stress changes produced by the earthquakes would have unclamped feeder dikes below the mud volcanoes. The magnitude of increased discharge, however, is less than that inferred from the large clasts. Both historical accounts and erupted deposits are consistent in recording episodic large eruptions.
NASA Astrophysics Data System (ADS)
Özmaral, A.; Çagatay, M. N.; Imren, C.; Gasperini, L.; Henry, P.
2012-04-01
Gemlik Gulf is an oval-shaped transtensional basin with a maximum depth of 113 m, located on the middle strand of the North Anatolian Fault (NAF) in the eastern part of the Sea of Marmara (SOM). During the last glacial period until the Holocene marine transgression about 12 ka BP, the sea level was below the Çanakkale (Dardanelles) Strait's bedrock sill depth of -85 m, and the Gemlik Basin became a lake isolated lake from the rest of the Sea of Marmara "Lake" and the global ocean. The high resolution seismic profiles and the multi- beam bathymetric map of the basin show that the basin is characterized by NW-SE trending transtensional oblique faults, delta lobes of the Büyükdere (Kocadere) to the east and an erosional surface below an up to 15 m-thick Holocene mud drape. The Holocene mud drape was studied in up to 9.5 m-long gravity-piston and 0.84 m-long sediment/water interface cores located at -105 to -113 m in the basin's depocentre. The Holocene mud consists mainly of plastic gray green marine clayey mud that includes thick-red brown clay layers and a laminated organic-rich, dark olive green sapropel in the lower part, which was previously dated at 11.6-6.4 14Ckyr (uncalib) BP. Multi-proxy analyses of the Holocene mud drape in the sediment cores were carried out using Multisensor Core Logger, XRF Core Scanner equipped with digital X-Ray radiography, and laser particle size analyzer. Seismic-core correlation was made using seismic data of the chirp profiles at the core locations and the synthetic seismograms generated using the MSCL P-wave velocity and gamma density measurements. The long piston-gravity cores include five 20 to 100 mm-thick "red brown mud layers" in the top 2.5 m of the core. These layers have a sharp basal boundary and gradational upper boundary. The red brown layers consist of 55-75% clay-size material with an average grain size of 3-4 µm, and have relatively a high magnetic susceptibility. They are enriched in K, Fe, Ti and Zr that are the proxy of detrital mineral input, and depleted in Ca, Br, Fe and Mn. Manganese shows a sharp enrichment immediately below the base of the red brown layers. All these features strongly suggest that the red layers represent the distal edges mass flow deposits, possibly sourced from the delta to the east. The distinct Mn enrichments below the base of the red brown layers represent the diagenetic enrichment at the oxic/anoxic boundary near the seafloor, which was later covered by the mass flow deposit. C-14 and radionuclide datings of the mass flow layers and investigation of their possible relation to the past earthquakes are under progress.
Recycling red mud from the production of aluminium as a red cement-based mortar.
Yang, Xiaojie; Zhao, Jianfeng; Li, Haoxin; Zhao, Piqi; Chen, Qin
2017-05-01
Current management for red mud is insufficient and a new method is needed. A series of experiments have been carried out to develop a new approach for effective management of red mud. Mortars without or with 3%, 6% and 9% red mud were prepared and their fresh and hardened properties were measured to access the possibility of recycling the red mud in the production of red cement-based mortar. The mechanisms corresponding to their mechanical performance variations were explored by X-ray powder diffraction and scanning electron microscopy. The results show that the fresh mortars with red mud present an increase of viscosity as compared with the control. However, little difference is found when the content of red mud is altered. It also can be seen that red mud increases flow time and reduces the slump flow of the mortar. Meanwhile, it is found that mortar with red mud is provided with higher air content. Red mud is eligible to adjust the decorative mortar colour. Compressive strength of mortar is improved when less than 6% red mud is added. However, overall it has a slightly negative effect on tensile bond strength. It decreases the Ca(OH) 2 content and densifies the microstructure of hardened paste. The heavy metal concentrations in leachates of mortars with red mud are much lower than the values required in the standard, and it will not do harm to people's health and the environment. These results are important to recycle and effectively manage red mud via the production of red cement-based mortar.
NASA Astrophysics Data System (ADS)
Feng, Zhibing; Liu, Baohua; Zhao, Yuexia; Li, Xishuang; Dada, Olusegun A.; Jiang, Li; Si, Shaokun
2017-04-01
Utilizing the collected high-resolution seismic dataset and accompanying borehole and bathymetric data, we systematically evaluated the morphology, architecture, sedimentology, and evolution of erosional mud ridges within the inner East China Sea (ECS) shelf. We identified 20 mud ridges, i.e., seismic reflection profile crossings of exposed or buried mud ridges, which are 3.0-30.1 km in width and 2.5-17.3 m in height. The mud ridges are composed predominantly of gray clayey silt, and on seismic profiles contain parallel to subparallel reflectors. They formed around 10-12 ka BP within an estuarine environment. Scouring features of some mud ridges on the eastern part of the study area can be recognized. Consideration of the relative positions of mud ridges, together with the topographical features, enables us to map four linear mud ridges (LMRs). The SE-NW oriented LMRs are > 50 km in length, 3.0-9.5 km in width and running parallel to each other. They also display asymmetric shapes, with steeper slopes to the SW. The eastern segments of some LMRs are exposed on the present seafloor whereas other segments are mainly overlain by the mid- and late Holocene strata. Since the LMRs share similarities with the modern tidal sand ridges in shape and orientation, we hypothesize that they are formed under a uniform tidal current. Seismic data highlight that the internal reflectors of sand ridges consist of dipping clinoforms and are significantly different from LMRs, a feature which is largely due to the difference in grain-size composition of sediments between the inner and mid-outer ECS shelf. The mid- to outer ECS shelf is capped by coarser-grained sediments (i.e., medium to fine-grained), which were reworked and deposited at locations near the erosional areas under a polycyclic tidal current, thus forming multiphase sand ridges. However, fine-grained sediments (i.e., silty clay and clayey silt) overlain on the inner ECS shelf with light mass were carried far away from the erosional areas by the tidal currents, and the relict mud ridges were built. Evidence shows that the LMRs were formed by the early Holocene strata being scoured by a persistent southeasterly flowing current during 8-10 ka BP. The evolution of the LMRs occurred in three stages: (a) formation of the transgressional strata at 10-12 ka BP, (b) strong trough erosion at 8-10 ka BP, and (c) local adjustment (i.e., local erosion slightly and preservation) after 8 ka BP.
Sedimentary Facies and Stratigraphy of the Changjiang (Yangtze River) Delta
NASA Astrophysics Data System (ADS)
Dalrymple, R. W.; Zhang, X.; Lin, C. M.
2017-12-01
A disproportionate number of the world's largest deltas are tide-dominated or strongly tide-influenced, in part because the low gradient of these rivers allows the tide to penetrate far inland, generating strong tidal currents at the river mouth. These deltas also tend to be mud-dominated because a significant fraction of the bedload is trapped farther inland. Despite their great importance as sediment depo-centers, as analogues for ancient sedimentary successions, and as areas of intense human occupation, they are the most poorly understood coastal system. The Changjiang (Yangtze River), the 4th largest river in the world in terms of sediment discharge, is one such tide-dominated system, with a mean tidal range of 2.7 m and tidal-current speeds of 1 m/s at its mouth. It shows a fairly typical series of low-relief channels and bars in the mouth-bar area and passes seaward and down-drift into a coastal mud belt that extends 800 km to the south of the river mouth. The deposits from both the transgressive-phase and modern delta are all dominated by mud, except for the fluvial-channel deposits that are clean sand. Channel-floor deposits in areas with appreciable tidal influence contain abundant fluid-mud layers (1-3 cm thick), intercalated with relatively coarse sand; such mud layers show evidence of tidal cyclicity. The overlying tidal-bar deposits commonly become sandier upward because of the upward loss of fluid-mud layers. The tidal channels and bars that characterize the mouth-bar and delta-front area are dominated by randomly organized structureless mud layers, 5-30 cm thick, that are interpreted to be storm-generated fluid-mud deposits. These mud layers become less abundant upward, generating upward-sanding successions. These facies are very similar to those seen in the Amazon and Fly River deltas, suggesting that this is a common motif, and indicating the importance of fluid mud in the dynamics of such systems. Facies proximality can be determined by careful comparison of sand-size trends, tidal mud-layer thicknesses (relative to the turbidity maximum) and the abundance of wave-generated fluid-mud layers. Application of these concepts shows that the transgressive phase of the delta consists of three retrogradationally stacked parasequences, each 7-15 m thick, overlain by the 40 m-thick highstand delta.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mark Krauss and Catherine Birney
2011-05-01
This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 544: Cellars, Mud Pits, and Oil Spills, Nevada National Security Site, Nevada. This CR complies with the requirements of the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. The corrective action sites (CASs) within CAU 544 are located within Areas 2, 7, 9, 10, 12, 19, and 20 of the Nevada National Security Site. Corrective Action Unit 544 comprises the following CASs: • 02-37-08,more » Cellar & Mud Pit • 02-37-09, Cellar & Mud Pit • 07-09-01, Mud Pit • 09-09-46, U-9itsx20 PS #1A Mud Pit • 10-09-01, Mud Pit • 12-09-03, Mud Pit • 19-09-01, Mud Pits (2) • 19-09-03, Mud Pit • 19-09-04, Mud Pit • 19-25-01, Oil Spill • 19-99-06, Waste Spill • 20-09-01, Mud Pits (2) • 20-09-02, Mud Pit • 20-09-03, Mud Pit • 20-09-04, Mud Pits (2) • 20-09-06, Mud Pit • 20-09-07, Mud Pit • 20-09-10, Mud Pit • 20-25-04, Oil Spills • 20-25-05, Oil Spills The purpose of this CR is to provide documentation supporting the completed corrective actions and data confirming that the closure objectives for CASs within CAU 544 were met. To achieve this, the following actions were performed: • Review the current site conditions, including the concentration and extent of contamination. • Implement any corrective actions necessary to protect human health and the environment. • Properly dispose of corrective action and investigation wastes. • Document Notice of Completion and closure of CAU 544 issued by the Nevada Division of Environmental Protection.« less
Liu, James T; Hsu, Ray T; Yang, Rick J; Wang, Ya Ping; Wu, Hui; Du, Xiaoqin; Li, Anchun; Chien, Steven C; Lee, Jay; Yang, Shouye; Zhu, Jianrong; Su, Chih-Chieh; Chang, Yi; Huh, Chih-An
2018-03-09
Globally mud areas on continental shelves are conduits for the dispersal of fluvial-sourced sediment. We address fundamental issues in sediment dynamics focusing on how mud is retained on the seabed on shallow inner shelves and what are the sources of mud. Through a process-based comprehensive study that integrates dynamics, provenance, and sedimentology, here we show that the key mechanism to keep mud on the seabed is the water-column stratification that forms a dynamic barrier in the vertical that restricts the upward mixing of suspended sediment. We studied the 1000 km-long mud belt that extends from the mouth of the Changjiang (Yangtze) River along the coast of Zhejiang and Fujian Provinces of China and ends on the west coast of Taiwan. This mud belt system is dynamically attached to the fluvial sources, of which the Changjiang River is the primary source. Winter is the constructive phase when active deposition takes place of fine-grained sediment carried mainly by the Changjiang plume driven by Zhe-Min Coastal Currents southwestward along the coast.
The Guadalquivir Diapiric Ridge: Deep Tectonics and Related Gas Structures
NASA Astrophysics Data System (ADS)
Fernández-Puga, M. C.; Somoza, L.; Pinheiro, L. M.; Magalhães, V.; Vázquez, J. T.; Díaz-del-Río, V.; Ivanov, M.
Cooperation between the Spanish TASYO project during the cruises Tasyo/2000, Anastasya/99, Anastasya/00 and Anastasya/01 and the UNESCO-IOC Trainning Trough Research Programme during the TTR9, TTR10 and TTR-11 cruises have per- mitted to identify numerous structures related to hydrocarbon seepages in the Gulf of Cadiz, located between the Africa and Eurasia plate. The interpretation of multibeam bathymetry and a large database of reflection seismic profiles shows two important morphotectonics structures: the Cadiz Diapiric Ridge (CDR) and the Guadalquivir Di- apiric Ridge (GDR). The CDR is a diapiric elongate structure located between 400 and 700m water depth, with a N-S direction. The GDR is an elongated ridge, situated west- ward of this structure and located along the shelf and slope between 300-1100m depth. This highly deformed ridge, formed by several diapirs oriented in NE-SW direction, has been mapped using industrial multifold seismic, core logs, gravity cores, dredge samples and photographs, obtained during the ANASTASYA 01/09 cruise. This data has shown that it is composed of early-middle Miocene blue marls (Maldonado et al, 1999), mud breccias and calcarenites. In fact, this diapiric structure is associated with a complex tectono-sedimentary history related to along slope gravity gliding and tec- tonic compression westward the fronts of the deformed wedges of the SOlistostromic & cedil;allochtonous unitsT (Somoza et al., 1999). According to the observed and sampled structures along the GDR, this ridge can be divided in three areas: (a) The NE area is characterized by the existence of a series of wide single sub-circular mud volcanoes (Anastasya, Tarsis and Pipoca), surrounded by a ring shaped seafloor depression. Mud breccia has been collected from these mud volcanoes (ANAS00-TG5,TG6,TG7,TG8 and ANAS01-TG2); (b) a central sector with long rounded-like crater structures, of unknown origin, from which calcarenites were collected (ANAS01-DA13); and (c) a SW sector, between 8zW and 7z40`W, that is caracterized by a series of mud mounds boundarying the Cadiz channel: Iberico, Cornide and Hormigas. In this area, abundant carbonate chimneys, slab and calcarenites were collected (ANAS00-DA10, ANAS01-DA1,DA2,DA15). All these seabed structures suggest high-pressure expul- sion of methane-enriched muds along thrusting faults. This research has been supported by the "TASYO" project (Tecto-sedimentary transfer 1 from shelf to Horseshoe and Seine abyssal plains in the Gulf of Cadiz) of the Spanish- funded Marine Science and Technology programme (CYTMAR 98-0209) in the frame of the Spanish-Portuguese agreement for scientific co-operation. References: Maldonado, A.,Somoza, L., Pallarés, L., 1999. The Betic orogen and the Iberian- African boundary in the Gulf of Cadiz : geological evolution (Central North Atlantic). Mar. Geol., 155, 9-43. Somoza, L., Maestro, A., Lowrie, A., 1999. Allochtonous Blocks as Hydrocarbon Traps in the Gulf of Cadiz. Offshore Technology Conference OTC 10889, 571-577. 2
Systematics of Alkali Metals in Pore Fluids from Serpentinite Mud Volcanoes: IODP Expedition 366
NASA Astrophysics Data System (ADS)
Wheat, C. G.; Ryan, J.; Menzies, C. D.; Price, R. E.; Sissmann, O.
2017-12-01
IODP Expedition 366 focused, in part, on the study of geochemical cycling, matrix alteration, material and fluid transport, and deep biosphere processes within the subduction channel in the Mariana forearc. This was accomplished through integrated sampling of summit and flank regions of three active serpentinite mud volcanoes (Yinazao (Blue Moon), Asùt Tesoro (Big Blue), and Fantangisña (Celestial) Seamounts). These edifices present a transect of depths to the Pacific Plate, allowing one to characterize thermal, pressure and compositional effects on processes that are associated with the formation of serpentinite mud volcanoes and continued activity below and within them. Previous coring on ODP Legs 125 and 195 at two other serpentinite mud volcanoes (Conical and South Chamorro Seamounts) and piston, gravity, and push cores from several other Mariana serpentinite mud volcanoes add to this transect of sites where deep-sourced material is discharged at the seafloor. Pore waters (149 samples) were squeezed from serpentinite materials to determine the composition of deep-sourced fluid and to assess the character, extent, and effect of diagenetic reactions and mixing with seawater on the flanks of the seamounts as the serpentinite matrix weathers. In addition two Water Sampler Temperature Tool (WSTP) fluid samples were collected within two of the cased boreholes, each with at least 30 m of screened casing that allows formations fluids to discharge into the borehole. Shipboard results for Na and K record marked seamount-to-seamount differences in upwelling summit fluids, and complex systematics in fluids obtained from flank sites. Here we report new shore-based Rb and Cs measurements, two elements that have been used to constrain the temperature of the deep-sourced fluid. Data are consistent with earlier coring and drilling expeditions, resulting in systematic changes with depth (and by inference temperature) to the subduction channel.
Alternatives Analysis Amchitka Island Mud Pit Cap Repair, Amchitka, Alaska January 2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Darr, Paul S.
2016-01-01
The U.S. Department of Energy (DOE) Office of Legacy Management (LM) manages the Nevada Offsites program, which includes a series of reclaimed drilling mud impoundments on Amchitka Island, Alaska (Figure 1). Navarro Research and Engineering, Inc. is the Legacy Management Support contractor (the Contractor) for LM. The Contractor has procured Tetra Tech, Inc. to provide engineering support to the Amchitka mud pit reclamation project. The mud pit caps were damaged during a 7.9-magnitude earthquake that occurred in 2014. The goals of the current project are to investigate conditions at the mud pit impoundments, identify feasible alternatives for repair of themore » cover systems and the contents, and estimate relative costs of repair alternatives. This report presents descriptions of the sites and past investigations, existing conditions, summaries of various repair/mitigation alternatives, and direct, unburdened, order-of-magnitude (-15% to +50%) associated costs.« less
Nelson, C.H.; Baraza, J.; Maldonado, A.; Rodero, J.; Escutia, C.; Barber, J.H.
1999-01-01
The late Quaternary pattern of sedimentary facies on the Spanish Gulf of Cadiz continental shelf results from an interaction between a number of controlling factors that are dominated by the Atlantic inflow currents flowing southeastward across the Cadiz shelf toward the Strait of Gibraltar. An inner shelf shoreface sand facies formed by shoaling waves is modified by the inflow currents to form a belt of sand dunes at 10-20 m that extends deeper and obliquely down paleo-valleys as a result of southward down-valley flow. A mid-shelf Holocene mud facies progrades offshore from river mouth sources, but Atlantic inflow currents cause extensive progradation along shelf toward the southeast. Increased inflow current speeds near the Strait of Gibraltar and the strong Mediterranean outflow currents there result in lack of mud deposition and development of a reworked transgressive sand dune facies across the entire southernmost shelf. At the outer shelf edge and underlying the mid-shelf mud and inner shelf sand facies is a late Pleistocene to Holocene transgressive sand sheet formed by the eustatic shoreline advance. The late Quaternary pattern of contourite deposits on the Spanish Gulf of Cadiz continental slope results from an interaction between linear diapiric ridges that are oblique to slope contours and the Mediterranean outflow current flowing northwestward parallel to the slope contours and down valleys between the ridges. Coincident with the northwestward decrease in outflow current speeds from the Strait there is the following northwestward gradation of contourite sediment facies: (1) upper slope sand to silt bed facies, (2) sand dune facies on the upstream mid-slope terrace, (3) large mud wave facies on the lower slope, (4) sediment drift facies banked against the diapiric ridges, and (5) valley facies between the ridges. The southeastern sediment drift facies closest to Gibraltar contains medium-fine sand beds interbedded with mud. The adjacent valley floor facies is composed of gravelly, shelly coarse to medium sand lags and large sand dunes on the valley margins. By comparison, the northwestern drift contains coarse silt interbeds and the adjacent valley floors exhibit small to medium sand dunes of fine sand. Because of the complex pattern of contour-parallel and valley-perpendicular flow paths of the Mediterranean outflow current, the larger-scale bedforms and coarser-grained sediment of valley facies trend perpendicular to the smaller-scale bedforms and finer-grained contourite deposits of adjacent sediment drift facies. Radiocarbon ages verify that the inner shelf shoreface sand facies (sedimentation rate 7.1 cm/kyr), mid-shelf mud facies (maximum rate 234 cm/kyr) and surface sandy contourite layer of 0.2-1.2 m thickness on the Cadiz slope (1-12 cm/kyr) have deposited during Holocene time when high sea level results in maximum water depth over the Gibraltar sill and full development of the Atlantic inflow and Mediterranean outflow currents. The transgressive sand sheet of the shelf, and the mud layer underlying the surface contourite sand sheet of the slope, correlate, respectively, with the late Pleistocene sea level lowstand and apparent weak Mediterranean outflow current.
NASA Astrophysics Data System (ADS)
Choi, Kyungsik; Kim, Do Hyeong
2016-06-01
Tidal dunes with well-defined rhythmic tidal bundles are documented from the lower intertidal zone of an open-coast macrotidal environment in Gyeonggi Bay, Korea. Based on combined morphologic, sedimentologic and hydrodynamic datasets, this study aims to characterize the factors that govern the temporal and spatial variability of tidal bundles in a non-barred, unconfined macrotidal environment. The tidal dunes are flood-asymmetric and of longer wavelength (10-20 m) with small ebb caps on the upper bank, and symmetric to slightly ebb-asymmetric and of shorter wavelength (5-10 m) with larger ebb caps on the lower bank. The upper-bank dunes are characterized by more steeply dipping flood-directed planar cross-beds and thinner mud drapes than the lower-bank dunes. Each tidal bundle consists of a single mud drape that is stratified to cross-stratified, rich in silt and very fine sand. It overlies ebb-directed ripples and represents dynamic mud deposition during the ebb tidal phase. The presence of strong rotary currents (up to 0.25 m/s) and low suspended-sediment concentration of flood currents prevent deposition of mud drapes during the high-tide slack-water period. The distinct asymmetry in the water elevation at which the velocity peaks during the ebb and flood phases results in the preferential preservation of flood-directed cross-beds in the lower intertidal zone, where the ebb current - although stronger than the flood currents - is of shorter duration and hence unable to reverse the dune profile. The pronounced time-velocity asymmetry at the higher elevation combined with the distinct velocity peak asymmetry leads to a better preservation of hierarchical tidal cycles in the upper-bank dunes. The present study suggests that the persistent occurrence of single, stratified to cross-stratified mud drapes, which reflect dynamic mud deposition during the ebb phase, and the dominance of flood-directed cross-beds are diagnostic features of tidal bundles in the intertidal zone of unbarred, open-coast macrotidal environments. A proposed model for mud drape deposition provides a new perspective on the origin of tidal bundles together with useful criteria for reconstructing the paleo-depositional setting.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lynn Kidman
This document constitutes an addendum to the November 2003, Closure Report for Corrective Action Unit 355: Area 2 Cellars/Mud Pits as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • Thismore » cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the cancellation of the URs for: • CAS 02-37-01, Cellar & Mud Pit • CAS 02-37-03, Cellar & Mud Pit • CAS 02-37-04, Cellar & Mud Pit • CAS 02-37-05, Cellar & Mud Pit • CAS 02-37-06, Cellar & Mud Pit • CAS 02-37-07, Cellar & Mud Pit • CAS 02-37-10, Cellar & Mud Pit • CAS 02-37-11, Cellar & Mud Pit • CAS 02-37-12, Cellar & Mud Pit • CAS 02-37-13, Cellar & Mud Pit • CAS 02-37-14, Cellar & Mud Pit • CAS 02-37-15, Cellar & Mud Pit • CAS 02-37-16, Cellar & Mud Pit • CAS 02-37-17, Cellar • CAS 02-37-18, Cellar & Tanks These URs were established as part of Federal Facility Agreement and Consent Order (FFACO) corrective actions and were based on the presence of contaminants at concentrations greater than the action levels established at the time of the initial investigation (FFACO, 1996; as amended August 2006). Since these URs were established, practices and procedures relating to the implementation of risk-based corrective actions (RBCA) have changed. Therefore, these URs were re-evaluated against the current RBCA criteria as defined in the Industrial Sites Project Establishment of Final Action Levels (NNSA/NSO, 2006c). This re-evaluation consisted of comparing the original data (used to define the need for the URs) to risk-based final action levels (FALs) developed using the current Industrial Sites RBCA process. The re-evaluation resulted in a recommendation to remove these URs because contamination is not present at these sites above the risk-based FALs. Requirements for inspecting and maintaining these URs will be canceled, and the postings and signage at each site will be removed. Fencing and posting may be present at these sites that are unrelated to the FFACO URs such as for radiological control purposes as required by the NV/YMP Radiological Control Manual (NNSA/NSO, 2004f). This modification will not affect or modify any non-FFACO requirements for fencing, posting, or monitoring at these sites.« less
NASA Astrophysics Data System (ADS)
Flury, Sabine; Røy, Hans; Dale, Andrew W.; Fossing, Henrik; Tóth, Zsuzsanna; Spiess, Volkhard; Jensen, Jørn Bo; Jørgensen, Bo Barker
2016-09-01
Shallow gas accumulates in coastal marine sediments when the burial rate of reactive organic matter beneath the sulfate zone is sufficiently high and the methanogenic zone is sufficiently deep. We investigated the controls on methane production and free methane gas accumulation along a 400 m seismo-acoustic transect across a sharp transition from gas-free into gas-bearing sediment in Aarhus Bay (Denmark). Twelve gravity cores were taken, in which the pore water was analyzed for inorganic solutes while rates of organic carbon mineralization were measured experimentally by 35SO42- radiotracer method. The thickness of organic-rich Holocene mud increased from 5 to 10 m along the transect concomitant with a shallowing of the depth of the sulfate-methane transition from >4 m to 2.5 m. In spite of drastic differences in the distribution of methane and sulfate in the sediment along the transect, there were only small differences in total mineralization, and methanogenesis was only equivalent to about 1% of sulfate reduction. Shallow gas appeared where the mud thickness exceeded 8-9 m. Rates of methanogenesis increased along the transect as did the upward diffusive flux of methane. Interestingly, the increase in the sedimentation rate and Holocene mud thickness had only a modest direct effect on methanogenesis rates in deep sediments. This increase in methane flux, however, triggered a shallowing of the sulfate-methane transition which resulted in a large increase in methanogenesis at the top of the methanogenic zone. Thus, our results demonstrate a positive feedback mechanism that causes a strong enhancement of methanogenesis and explains the apparently abrupt appearance of gas when a threshold thickness of organic-rich mud is exceeded.
NASA Astrophysics Data System (ADS)
Ozdemir, C. E.; Traykovski, P.
2014-12-01
Understanding the dynamics and the transport mechanisms of fluidmud is crucial to illuminate the details regarding the attenuation in the surface wave energy over muddy seabed and wave-supported gravity-driven mud flows that take place in nearshore environments. Although there is significant progress through theoretical, experimental, and numerical studies, little attention has been drawn to the intricate alteration in the fluidmud transport over bedforms that inherently exist in the actual field conditions. Specifically, interfacial waves at the fluidmud interface were observed in coastal Louisiana as a part of MURI field experiments in 2010. It is also observed that wave attenuation was dominated by viscous processes during laminar flow and attenuation decreased duing the transition to turbulence. Considering the slow growth of shear instability at the interface, bed forms have a critical role to initiate the growth of interfacial waves and the subsequent transition to turbulence. In this study, we investigate the role of bed forms on the dynamics of moderately thin fluidmud layer via large eddy simulations. Three mud viscosity values, based on the field observations, are tested for a 20 centimeters of mud layer over ripples: (i)ν = 1 x 10-3, (ii) ν = 1 x 10-4 , and (iii) ν = 1 x 10-5 . In Case (i), wave energy dissipation is nearly the same as the one over a flat bed. Case (ii) shows that there is a 10 to 20 percent increase in the wave energy dissipation especially at the fluidmud interface. Finally, in Case (iii), we observe the high-energy transitional flow characteristics. In this presentation, we shall also share the detailed analyses of these simulations.
NASA Astrophysics Data System (ADS)
Chun, Jong-Hwa; Kim, Yuri; Bahk, Jang-Jun; Kim, Young Jun; Kang, Dong-Hyo; Kim, Yong Hoon; Kim, Gil Young; Ryu, Byong-Jae
2015-12-01
The distal mud deposits (DMDs) off the Nakdong delta represent a subaqueous delta on the inner continental shelf aligned parallel to the southeast coast of Korea and displaying a clinoform geometry. Hydrographically, the coast is characterized by a micro-tidal regime, the strong Korean Coastal Current (KCC) and the East Korean Warm Current (EKWC). Age models and sedimentary facies related to the clinoform geometries are based on high-resolution chirp subbottom profile data and have provided information on shore-parallel sediment transport and accumulation during the late Holocene sea-level highstand. The highest sedimentation rates (6.19-9.17 cm/year) produced steep foresets in the central DMDs at water depths of 35-50 m. Here, vertical burrows are repeatedly truncated by laminated mud packages displaying erosional surfaces. This region represents the main depocenter of the Nakdong subaqueous delta. The topset sediments of the southern DMD at ~40 m water depth closer to the river mouth show relatively low sedimentation rates (0.01-0.12 cm/year). Here, the muds have a predominantly mottled character. Similarly, the foreset sediments of the northern DMD at ~71-80 m water depth with sedimentation rates of 0.10-2.03 cm/year are also predominantly characterized by mottled muds. The spatial dispersal pattern of the DMDs is consistent with the coast-parallel front between the KCC and EKWC along the southeast Korean coast. In addition, the depocenter of the Nakdong subaqueous delta clinoform is affected by the near-bed turbulence generated by episodic storm events.
An, Junyeong; Lee, Soo-Jin; Ng, How Yong; Chang, In Seop
2010-12-01
We examined the possibility of harvesting electricity from the surface of a tidal mud flat using a cylindrical-type sediment microbial fuel cell (SMFC), a marine mud battery (MMB), which can be applied in a sea environment where the ebb and flow occur due to tidal difference. In addition, we indirectly investigated the influence of ebb and flow in a lab, using aeration, argon gassing, and by agitating the cathodic solution. The MMBs consisted of cylindrical acrylic compartments containing a nylon membrane, an anode, and a cathode in a single body. The MMBs were stuck vertically into an artificial tidal mud flat such that the anode electrode was in direct contact with the tidal mud surface. As a result, the maximum current and power density generated were 35 mA/m(2) and 9 mW/m(2), respectively, thus verifying that it is possible to harvest electricity from the surface of a tidal mud flat using an MMB without burying the anode electrode in the tidal mud. Furthermore, the results of tests using an artificial turbulence flow showed the flow induced by the tidal ebb and flow could allow the performance of MMBs to be enhanced. Copyright © 2010 Elsevier Ltd. All rights reserved.
Management of fluid mud in estuaries, bays, and lakes. II: Measurement, modeling, and management
McAnally, W.H.; Teeter, A.; Schoellhamer, David H.; Friedrichs, C.; Hamilton, D.; Hayter, E.; Shrestha, P.; Rodriguez, H.; Sheremet, A.; Kirby, R.
2007-01-01
Techniques for measurement, modeling, and management of fluid mud are available, but research is needed to improve them. Fluid mud can be difficult to detect, measure, or sample, which has led to new instruments and new ways of using existing instruments. Multifrequency acoustic fathometers sense neither density nor viscosity and are, therefore, unreliable in measuring fluid mud. Nuclear density probes, towed sleds, seismic, and drop probes equipped with density meters offer the potential for accurate measurements. Numerical modeling of fluid mud requires solving governing equations for flow velocity, density, pressure, salinity, water surface, plus sediment submodels. A number of such models exist in one-, two-, and three-dimensional form, but they rely on empirical relationships that require substantial site-specific validation to observations. Management of fluid mud techniques can be classified as those that accomplish: Source control, formation control, and removal. Nautical depth, a fourth category, defines the channel bottom as a specific fluid mud density or alternative parameter as safe for navigation. Source control includes watershed management measures to keep fine sediment out of waterways and in-water measures such as structures and traps. Formation control methods include streamlined channels and structures plus other measures to reduce flocculation and structures that train currents. Removal methods include the traditional dredging and transport of dredged material plus agitation that contributes to formation control and/or nautical depth. Conditioning of fluid mud by dredging and aerating offers the possibility of improved navigability. Two examples—the Atchafalaya Bar Channel and Savannah Harbor—illustrate the use of measurements and management of fluid mud.
Recovery of value-added products from red mud and foundry bag-house dust
NASA Astrophysics Data System (ADS)
Hammond, Keegan
"Waste is wasted if you waste it, otherwise it is a resource. Resource is wasted if you ignore it and do not conserve it with holistic best practices and reduce societal costs. Resource is for the transformation of people and society." Red mud is a worldwide problem with reserves in the hundreds of millions of tons and tens of millions of tons being added annually. Currently there is not an effective way to deal with this byproduct of the Bayer Process, the primary means of refining bauxite ore in order to provide alumina. This alumina is then treated by electrolysis using the Hall-Heroult process to produce elemental aluminum. The resulting mud is a mixture of solid and metallic oxides, and has proven to be a great disposal problem. This disposal problem is compounded by the fact that the typical bauxite processing plant produces up to three times as much red mud as alumina. Current practice of disposal is to store red mud in retention ponds until an economical fix can be discovered. The danger associated with this current method of storage is immense to the surrounding communities and environment, thus the interest from the Center for Resource Recovery and Recycling (CR3). The purpose of this document is to explain one way to remove the value added materials, primarily iron, from the Jamaican red mud using both pyrometallurgical and hydrometallurgical approaches. In the beginning, soda ash and carbon roasting were completed simultaneously at 800°C. This type of roasting produced results that were unacceptable. After the soda ash roast was completed independently of carbon roasting, a water wash produced results that separations of alumina at 90%, Iron at 99%, calcium at 99%, titanium t 100%, and sodium by 74%. Smelting produced separations of 97% for alumina, 99% for iron, 87% for sodium, 94% for calcium and 72% for titanium.
Cai, J.; Powell, R.D.; Cowan, E.A.; Carlson, P.R.
1997-01-01
High-resolution seismic-reflection profiles of sediment fill within Tart Inlet of Glacier Bay, Alaska, show seismic facies changes with increasing distance from the glacial termini. Five types of seismic facies are recognized from analysis of Huntec and minisparker records, and seven lithofacies are determined from detailed sedimentologic study of gravity-, vibro- and box-cores, and bottom grab samples. Lithofacies and seismic facies associations, and fjord-floor morphology allow us to divide the fjord into three sedimentary environments: ice-proximal, iceberg-zone and ice-distal. The ice-proximal environment, characterized by a morainal-bank depositional system, can be subdivided into bank-back, bank-core and bank-front subenvironments, each of which is characterized by a different depositional subsystem. A bank-back subsystem shows chaotic seismic facies with a mounded surface, which we infer consists mainly of unsorted diamicton and poorly sorted coarse-grained sediments. A bank-core depositional subsystem is a mixture of diamicton, rubble, gravel, sand and mud. Seismic-reflection records of this subsystem are characterized by chaotic seismic facies with abundant hyperbolic diffractions and a hummocky surface. A bank-front depositional subsystem consists of mainly stratified and massive sand, and is characterized by internal hummocky facies on seismic-reflection records with significant surface relief and sediment gravity flow channels. The depositional system formed in the iceberg-zone environment consists of rhythmically laminated mud interbedded with thin beds of weakly stratified diamicton and stratified or massive sand and silt. On seismic-reflection profiles, this depositional system is characterized by discontinuously stratified facies with multiple channels on the surface in the proximal zone and a single channel on the largely flat sediment surface in the distal zone. The depositional system formed in the ice-distal environment consists of interbedded homogeneous or laminated mud and massive or stratified sand and coarse silt. This depositional system shows continuously stratified seismic facies with smooth and flat surfaces on minisparker records, and continuously stratified seismic facies which are interlayered with thin weakly stratified facies on Huntec records.
NASA Astrophysics Data System (ADS)
Yang, C.; Wang, T.; Chen, Z.
2016-12-01
Separate interpretation of the evidence on tectonic, sedimentology or climate is insufficient to reappear the dynamic process of the evolution of the Earth surface, thus, tectonic, sedimentology and climate should be considered as a coupled system. Thick carbonate succession is overlaying on the paleo-uplift which is divided into two parts by a fluted belt in the center of Sichuan Basin. Sinian carbonate rocks is commonly composed by algae dolomite, while at the top of the Sinian succession the rocks had experienced meteoric karstification. Grain dolostones, fine-grained siliciclastic sandstones with mudstone appeare as the regional sediment of Cambrian. However, extraordinary thick mudstone had settled in the fluted belt, and the succession could be divided in to siliciclastic mud of the lower and clay-carbonate mud of the upper. The geochemistry and well log synthesized profile of Z4 well indicate that the chemical condition of siliciclastic mud and clay-carbonate mud had changed from oxidation to reduction, however the siliciclastic mud only appeared within the fluted belt. The fluted belt does not exist on the map of the gravity anomaly, but it had been convinced by the seismic data. The precursor of the fluted belt might be a sag within the platform basement, while with the sea level gradually raising up, the growth of algal mound exacerbated the geomorphology difference. Then a regression had happened at the end of the Sinian, starved all the algae and caused weather crust. Meanwhile, the fluted belt became a closed lagoon, received the sediment including algal mound fragment and biosilic crystals. Afterwards, rapidly increasing of the sea level deposited thick cay-carbonate mud that could be recognized as the sediment of maximum flooding surface. Then with the sea level decreasing, siliciclastic sandstones and inorganic grain carbonate became the main petrology of the Cambrian strata. Fine-grained eolian siliciclastic sandstones within the Cambrian carbonate indicate the influence of the continent, but this terrigenous clastics not exist in Sinian carbonate because the location of the platform moved closer to the continent in Cambrian. Meanwhile, there is no algal within Cambrian carbonate, it means the platform might drift to inhospitable place for the algal during the period.
Methane Hydrate Recovered From A Mud Volcano in Santa Monica Basin, Offshore Southern California
NASA Astrophysics Data System (ADS)
Normark, W. R.; Hein, J. R.; Powell, C. L.; Lorenson, T. D.; Lee, H. J.; Edwards, B. D.
2003-12-01
In July 2003, a short (2.1 m) piston core from the summit of a mud volcano recovered methane hydrate at a water depth of 813 m in Santa Monica Basin. The discovery core penetrated into in the hydrate as evidenced by chunks of ice and violent degassing of the core section between 162 and 212 cm depth. The core consists of shell hash and carbonate clasts (to 7-cm long) in silty mud. The methanogenic carbonates are of two types: massive, recrystallized nodular masses with an outer mm-thick sugary patina and a bivalve coquina with carbonate cement. Living clams including the genus Vesicomya, commonly found at cold-seep sites elsewhere, were recovered from the top of the core. Further sampling attempts using piston, gravity, and box corers, all of which were obtained within 15 m of the discovery core, recovered olive-brown silty mud with variable amounts of whole and fragmented bivalve shells and methanogenic carbonate fragments characteristic of cold-seep environments. Gases collected in cores adjacent to the discovery core contain elevated amounts of methane and trace amounts of heavier hydrocarbon gases, indicating some component from thermogenic sources. Hydrogen sulfide was also detected in these sediment samples. Vertical channels in one core may have served as fluid pathways. The existence of hydrate at such a shallow depth in the sediment was unexpected, however, the presence of Vesicomya and hydrogen sulfide indicate that the mud volcano is a site of active methane venting. The mud volcano, which is about 24 km west-southwest of Redondo Beach, is about 300 m in diameter at the base. No internal structure is resolved on either high resolution deep-tow boomer or single-channel air-gun profiles, most likely as a result of the gas content and sediment deformation. The diapiric structure has ascended through well-bedded sediment on the lower slope of the basin, producing as much as 30 m of bathymetric relief. It is located in an area where strike-slip motion along the San Pedro Basin fault zone to the south is replaced by convergent motion to the north. The source horizon for the gas in the hydrate is unknown but appears to be collecting in beds as shallow as 200 m below the regional seafloor based on the presence of a strong and irregular reflection interval.
Tide-driven fluid mud transport in the Ems estuary
NASA Astrophysics Data System (ADS)
Becker, Marius; Maushake, Christian; Winter, Christian
2014-05-01
The Ems estuary, located at the border between The Netherlands and Germany, experienced a significant change of the hydrodynamic regime during the past decades, as a result of extensive river engineering. With the net sediment transport now being flood-oriented, suspended sediment concentrations have increased dramatically, inducing siltation and formation of fluid mud layers, which, in turn, influence hydraulic flow properties, such as turbulence and the apparent bed roughness. Here, the process-based understanding of fluid mud is essential to model and predict mud accumulation, not only regarding the anthropogenic impact, but also in view of the expected changes of environmental boundary conditions, i.e., sea level rise. In the recent past, substantial progress has been made concerning the understanding of estuarine circulation and influence of tidal asymmetry on upstream sediment accumulation. While associated sediment transport formulations have been implemented in the framework of numerical modelling systems, in-situ data of fluid mud are scarce. This study presents results on tide-driven fluid mud dynamics, measured during four tidal cycles aside the navigation channel in the Ems estuary. Lutoclines, i.e., strong vertical density gradients, were detected by sediment echo sounder (SES). Acoustic Doppler current profiles (ADCP) of different acoustic frequencies were used to determine hydrodynamic parameters and the vertical distribution of suspended sediment concentrations in the upper part of the water column. These continuous profiling measurements were complemented by CTD, ADV, and OBS casts. SES and ADCP profiles show cycles of fluid mud entrainment during accelerating flow, and subsequent settling, and the reformation of a lutocline during decelerating flow and slack water. Significant differences are revealed between flood and ebb phase. Highest entrainment rates are measured at the beginning of the flood phase, associated with strong current shear and rapid vertical mixing, inducing the highest instantaneous suspended sediment flux measured during the tidal cycle. During decelerating flood currents a lutocline is again established at a certain distance above the consolidated river bed. During slack water after the flood phase the concentration gradient increases and the thickness of the fluid mud layer below is constant, also during a significant part of the ebb phase. As water depth decreases during ebb, entrainment occurs only at the upper part of the fluid mud layer. The suspended sediment flux is low compared to the flood phase. These observations are further elaborated using turbulence parameters obtained from ADV and ADCP, explaining the difference between ebb and flood concerning the vertical location of the maximum concentration gradient. This study is funded through DFG-Research Center / Excellence Cluster "The Ocean in the Earth System". The Senckenberg Institute and the Federal Waterways Engineering and Research Institute are acknowledged for technical support.
Sedimentation rates in the marshes of Sand Lake National Wildlife Refuge
Gleason, R.A.; Euliss, N.H.; Holmes, C.W.
2003-01-01
Impoundments located within river systems in the Northern Great Plains are vulnerable to sediment inputs because intensive agriculture in watersheds has increased soil erosion and sediments in rivers. At the request of the U.S. Fish and Wildlife Service (FWS), we evaluated the vertical accretion of sediment in the Mud Lake impoundment of Sand Lake National Wildlife Refuge (NWR), Brown County, South Dakota. The Mud Lake impoundment was created in 1936 by constructing a low-head dam across the James River. We collected sediment cores from the Mud Lake impoundment during August 2000 for determination of vertical accretion rates. Accretion rates were estimated using cesium-13 7 and lead-210 isotopic dating techniques to estimate sediment accretion over the past 100 years. Accretion rates were greatest near the dam (1.3 cm yr-1) with less accretion (0.2 cm yr-1) occurring in the upper reaches of Mud Lake. As expected, accretion was highest near the dam where water velocities and greater water depth facilitates sediment deposition. Higher rates of sedimentation (accretion> 2.0 cm year-1) occurred during the 1990s when river flows were especially high. Since 1959, sediment accretion has reduced maximum pool depth of Mud Lake near the dam by 55 cm. Assuming that sediment accretion rates remain the same in the future, we project Mud Lake will have a maximum pool depth of 77 and 51 cm by 2020 and 2040, respectively. Over this same time frame, water depths in the upper reaches of Mud Lake would be reduced to< 2 cm. Projected future loss of water depth will severely limit the ability of managers to manipulate pool levels in Mud Lake to cycle vegetation and create interspersion of cover and water to meet current wildlife habitat management objectives. As predicted for major dams constructed on rivers throughout the world, Mud Lake will have a finite life span. Our data suggests that the functional life span of Mud Lake since construction will be < 100 years. We anticipate that over the next 20 years, sediments entering Mud Lake will reduce water depths to the point that current wildlife management objectives cannot be achieved through customary water-level manipulations. Sedimentation impacts are not unique to the Sand Lake NWR. It is widely accepted that impoundments trap sediments and shallow impoundments, such as those managed by the FWS, are especially vulnerable. Given the ecological impacts associated with loss of water depths, we recommend that managers begin evaluating the long-term wildlife management goals for the refuge relative to associated costs and feasibility of options available to enhance and maximize the life span of existing impoundments, including upper watershed management.
NASA Astrophysics Data System (ADS)
Mont'Alverne, Renata; Moraes, Leonardo E.; Rodrigues, Fábio L.; Vieira, João P.
2012-05-01
Using fluid mud deposition events which occur regularly at Cassino Beach in south Brazil, we evaluated the influence of such events on the structure of the ichthyofauna inhabiting its shallow surf zone. Wave action was the dominant factor in differentiating between sampling sites, being lower or even absent at the mud-influenced sectors compared to beach area without mud. Samples were collected using a beach seine net at two control locations (A1 and A2), and at three locations influenced by mud deposition (B1, B2, and B3). During the study period (21 April-04 August 2009), 15,245 fishes were captured and separated into 26 taxonomic groups, from species to family. Individuals of a total length (TL) up to 50 mm accounted for 65% of the catch, while individuals of TL < 30 mm were the most numerous and more responsible for the total abundance spatial pattern. The area with higher wave action (A2) had the lowest relative species abundance and greatest diversity, whereas the areas with mud-forced lowest wave action (B2 and B3) had the highest species abundance values. Three hypotheses were proposed to explain the higher concentration and capture of juvenile fishes at mud locations. First, longshore currents may be responsible for the displacement of juvenile aggregations toward areas of lower energy. Second, individuals may select habitats with turbid waters, which may provide greater protection from predators and increased food availability. Third, areas under the influence of fluid mud deposition show higher values of viscosity, which may reduce swimming activity and hinder the escape of juvenile fishes from nets, resulting in an increased capture of individuals compared to areas without mud.
Zhang, Na; Liu, Xiaoming; Sun, Henghu; Li, Longtu
2011-01-15
Red mud is generated from alumina production, and its disposal is currently a worldwide problem. In China, large quantities of red mud derived from bauxite calcination method are being discharged annually, and its utilization has been an urgent topic. This experimental research was to evaluate the feasibility of blends red mud derived from bauxite calcination method with other industrial wastes for use as a cementitious material. The developed cementitious material containing 30% of the bauxite-calcination-method red mud possessed compressive strength properties at a level similar to normal Portland cement, in the range of 45.3-49.5 MPa. Best compressive strength values were demonstrated by the specimen RSFC2 containing 30% bauxite-calcination-method red mud, 21% blast-furnace slag, 10% fly ash, 30% clinker, 8% gypsum and 1% compound agent. The mechanical and physical properties confirm the usefulness of RSFC2. The hydration characteristics of RSFC2 were characterized by XRD, FTIR, (27)Al MAS-NMR and SEM. As predominant hydration products, ettringite and amorphous C-S-H gel are principally responsible for the strength development of RSFC2. Comparing with the traditional production for ordinary Portland cement, this green technology is easier to be implemented and energy saving. This paper provides a key solution to effectively utilize bauxite-calcination-method red mud. Copyright © 2010 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Casadevall, T. J.
2009-12-01
In June 2007, the US Department of State (DOS) requested assistance from the USGS to provide technical guidance and advice to the US Mission in Indonesia regarding the Lumpur Sidoarjo (LUSI) mud crisis. In May 2006, LUSI began as a mud eruption from a series of mud springs adjacent to an oil and gas exploration well being drilled near Surabaya, East Java, Indonesia. The production of mud and waters from the LUSI crater area has now continued for more than 3 years with no significant change in mud production rate (~110,000 cubic meters per day) nor in temperature of the mud (70-80 degrees C). Engineers suggest that mud production will continue at these rates for years to decades to come. Regardless of future activity at LUSI, the current mud accumulation of more than 100 million cubic meters poses a physical and environmental hazard which requires continuous monitoring and observation. The first response to the 2007 DOS request involved a site visit to Indonesia in September 2007. The result of that visit was to recommend to the Government of Indonesia (GOI) that they focus on long-term management of the mud rather than focus on the controversy as to the cause of the eruption or the debate about stopping the flow. Other recommendations from the initial 2007 technical visit included contracting for a US scientist to be co-located with engineers of the Sidoarjo Mud Management Board (BPLS) in Surabaya, East Java, to advise and consult on day-to-day developments at the site of the mud eruption. A second technical team visit by USGS scientists and an engineer from the US Army Corps of Engineers in October-November 2008 made additional recommendations on the long-term management of the mud and was followed in December by the start of a 6 month contract for the US mud adviser. From the start of activity in mid-2006 through late-2008, there was a clear sense of urgency at the US Mission in Indonesia to provide guidance and advice and included the personal intervention of the new US Ambassador. The USGS has completed the requests made in the June 2007 DOS cable, including an initial characterization of the mud and fluids; an analysis of land surface changes using the INSAR method; and an assessment of the seismic hazards in East Java. In the coming year, USGS will assist DOI agencies in the geophysical monitoring of the LUSI area and in the continued characterization of mud and fluids produced by the eruption.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geslin, J.K.
1994-01-01
Upper Pennsylvanian to Lower Permian mixed siliciclastic-carbonate sandy turbidites from the Oquirrh-Wood River basin in southern Idaho contain 20 to 60 modal percent microspar and pseudospar. Previous interpretations suggested that neomorphism of detrital lime mud produced the observed carbonate textures. The original detrital lime mud produced the observed carbonate textures. The original detrital lime mud content, based on these interpretations, indicates matrix-rich, poorly sorted turbidite deposits. However, observed turbidite hydrodynamics, and grain-size data from experimental and naturally occurring sandy turbidite deposits, indicate that T[sub n]-T[sub c] intervals of sandy turbidites are generally moderately well sorted, with low matrix content. Fluorescencemore » microscopy reveals that the carbonate fraction of these mixed siliciclastic-carbonate turbidites contains micritized skeletal grains and fusulinids, and algal peloids. These micritized grains and peloids were physically compacted and neomorphosed to form a carbonate pseudomatrix. Formation of carbonate pseudomatrix is analogous to formation of pseudomatrix in siliciclastic lithic sands, which includes crushing and recrystallization of lithic grains. Grain-size analysis of siliciclastic and slightly compacted carbonate grains indicates that these are moderately well sorted turbidite deposits with similar grain-size populations in both fractions. Lack of recognition of carbonate pseudomatrix could lead to erroneous interpretations of carbonate petrology. Identification of carbonate pseudomatrix is important to the study of mixed siliciclastic-carbonate gravity-flow deposits. This study demonstrates the value of fluorescence microscopy in the recognition of carbonate pseudomatrix.« less
The use of mud as an alternative source for bioelectricity using microbial fuel cells
NASA Astrophysics Data System (ADS)
Darmawan, Raden; Widjaja, Arief; Juliastuti, Sri Rachmania; Hendrianie, Nuniek; Hidaya, Chanifah; Sari, Dessy Rosita; Suwito, Morimura, Shigeru; Tominaga, Masato
2017-05-01
Alternative energy sources to substitute fossil-based energy is expected, as the fossil energy reserves decreasing every day. Mud is considered to be economical as the material sources for generating the electricity where it could be found easily and abundantly in Indonesia. The existence of a lot of mud that contains organic material has great potential as a source of electrical energy using microbial fuel cells (MFCs). It provides a promising technology by degrading organic compounds to yield the sustainable energy. The different sampling sites were determined to find out the electricity production, i.e. mud from soil water, brackish water and sea water using an anode immersed of 10 cm2. The results suggest that the electricity generation of the three areas are 0.331, 0.327 and 0.398 V (in terms of voltage); 0.221, 0.050 and 0.325 mA (in terms of electric current), respectively. It is investigated that the mud obtained the sea water exhibits the highest power potential compared to that obtained from the brackish and soil water.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arnis Judzis
2002-10-01
This document details the progress to date on the OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE -- A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING contract for the quarter starting July 2002 through September 2002. Even though we are awaiting the optimization portion of the testing program, accomplishments include the following: (1) Smith International agreed to participate in the DOE Mud Hammer program. (2) Smith International chromed collars for upcoming benchmark tests at TerraTek, now scheduled for 4Q 2002. (3) ConocoPhillips had a field trial of the Smith fluid hammer offshore Vietnam. The hammer functioned properly, though themore » well encountered hole conditions and reaming problems. ConocoPhillips plan another field trial as a result. (4) DOE/NETL extended the contract for the fluid hammer program to allow Novatek to ''optimize'' their much delayed tool to 2003 and to allow Smith International to add ''benchmarking'' tests in light of SDS Digger Tools' current financial inability to participate. (5) ConocoPhillips joined the Industry Advisors for the mud hammer program. (6) TerraTek acknowledges Smith International, BP America, PDVSA, and ConocoPhillips for cost-sharing the Smith benchmarking tests allowing extension of the contract to complete the optimizations.« less
Sediment Dispersal Within Poverty Bay, Offshore of the Waipaoa River, New Zealand
NASA Astrophysics Data System (ADS)
Harris, C. K.; Bever, A. J.; McNinch, J. E.
2006-12-01
Transport processes change drastically as sediment crosses the boundary between land and sea. As such, developing conceptual or predictive models of transport and deposition for the shoreline and inner continental shelf is critical to understanding source-to-sink sedimentary systems. In shallow coastal areas, sediment dispersal results from both dilute suspensions driven by energetic waves and current shear stresses, and by gravitationally driven flows of fluid muds. The Waipaoa River, on the east coast of the North Island of New Zealand, delivers approximately 15 million tons per year of sediment to Poverty Bay, a small embayment with water depth less than about 25 m. Instruments deployed during the winter storm season of 2006 captured periods of high discharge from the Waipaoa River that were typically associated with energetic waves and winds from the southeast. During these times, instruments deployed at 9 and 14 m water depths recorded high turbidity. Currents measured in Poverty Bay were correlated with wind velocities, but also showed prolonged periods of offshore flow within the bottom boundary layer. Sediment texture throughout much of Poverty Bay is muddy, and thick deposits have occurred during the Holocene, as evidenced by sub-bottom seismics. Short-lived radioisotopes such as ^7Be have not been found on Poverty Bay sediments during our field work, though depocenters have been identified using ^7Be on the continental shelf. This may imply that muds exist there as ephemeral and spatially patchy deposits that may bypass Poverty Bay. Bypassing mechanisms may include offshore dispersal by dilute suspended sediment, and downslope transport of fluid muds. Energetic waves may resuspend sediment, which is then transported out of Poverty Bay by ambient ocean currents. Alternatively, fluid muds may form and transport material downslope and offshore to the continental shelf. Because of the high sediment loads of the Waipaoa River, these fluid muds may be formed by hyperpycnal river flows upon entering Poverty Bay. They may also be produced by frontal systems that focus newly delivered sediments, or within fluid muds confined to the thin near-bed wave boundary layer.
Map of Distribution of Bottom Sediments on the Continental Shelf, Gulf of Alaska
Evans, Kevin R.; Carlson, Paul R.; Hampton, Monty A.; Marlow, Michael S.; Barnes, Peter W.
2000-01-01
Introduction The U.S. Geological Survey has a long history of exploring marine geology in the Gulf of Alaska. As part of a cooperative program with other federal and state agencies, the USGS is investigating the relations between ocean-floor geology and benthic marine biohabitats. This bottom sediment map, compiled from published literature will help marine biologists develop an understanding of sea-floor geology in relation to various biological habitats. The pattern of sea-floor sedimentation and bottom morphology in the Gulf of Alaska reflects a complex interplay of regional tectonism, glacial advances and retreats, oceanic and tidal currents, waves, storms, eustatic change, and gravity-driven processes. This map, based on numerous cruises during the period of 1970-1996, shows distribution of bottom sediments in areas of study on the continental shelf. The samples were collected with piston, box, and gravity corers, and grab samplers. The interpretations of sediment distribution are the products of sediment size analyses combined with interpretations of high-resolution seismic reflection profiles. The sea floor was separated into several areas as follows: Cook Inlet -- Hazards studies in this embayment emphasized sediment distribution, sediment dynamics, bedforms, shallow faults, and seafloor stability. Migrating mega-sandwaves, driven by strong tidal currents, influence seabed habitats and stability of the seafloor, especially near pipelines and drilling platforms. The coarseness of the bottom sediment reinforces the influence of the strong tidal currents on the seafloor habitats. Kodiak Shelf -- Tectonic framework studies demonstrate the development of an accretionary wedge as the Pacific Plate underthrusts the Alaskan landmass. Seismic data across the accretionary wedge reveal anomalies indicative of fluid/gas vent sites in this segment of the continental margin. Geologic hazards research shows that movement along numerous shallow faults poses a risk to sea floor structures. Sea-floor sediment on shallow banks is eroded by seasonal wave-generated currents. The winnowing action of the large storm waves results in concentrations of gravel over broad segments of the Kodiak shelf. Northeastern Gulf of Alaska -- Tectonic framework studies demonstrate that rocks of distant origin (Yakutat terrane) are currently attached to and moving with the Pacific Plate, as it collides with and is subducted beneath southern Alaska. This collision process has led to pronounced structural deformation of the continental margin and adjacent southern Alaska. Consequences include rapidly rising mountains and high fluvial and glacial sedimentation rates on the adjacent margin and ocean floor. The northeastern Gulf of Alaska shelf also has concentrations of winnowed (lag) gravel on Tarr Bank and on the outer shelf southeast of Yakutat Bay. Between Kayak Island and Yakutat Bay the outer shelf consists of pebbly mud (diamict). This diamict is a product of glacial marine sedimentation during the Pleistocene and is present today as a relict sediment. A prograding wedge of Holocene sediment consisting of nearshore sand grading seaward into clayey silt and silty clay covers the relict pebbly mud to mid-shelf and beyond. Shelf and slope channel systems transport glacially derived sediment across the continental margin into Surveyor Channel, an abyssal fan and channel system that reaches over 1,000 km to the Aleutian Trench.
A Possible Origin of the Gas Hydrate in Southwest Taiwan Offshore Area
NASA Astrophysics Data System (ADS)
Lee, C.; Lee, J.; Oung, J.
2003-12-01
The southwest Taiwan locate at the eastward subduction zone of the Eurasian plate, which is currently converging with the Philippine Sea plate at a rate of several few centimeters per year. The geological setting of this region is characterized by the appearance of thick accreted sediments up to several kilometers, numerous submarine canyons, active faults, and mud diapirs/volcanoes. The origin of mud diapir/volcano is probably related to the plate convergence. During the tectonic processes, the organic matters were "cooked" thermogenically and biogenically to produce the natural gases, and possibly the oil in the sediment. Beneath the seafloor, if the natural gases were at the appropriate temperature and pressure condition, they would become the gas hydrate, and preserved in the top sediment layers. The formation of gas hydrate is situated under the water depth at about 300 to 3000 meters in this region. In the seismic profiles, the Bottom Simulation Reflector (BSR) probably represents the boundary between the solid-state and gas-state natural gas. The BSR is also regarded as an important marker as an existence of gas hydrate. It is extensively distributed in the continental margin off southwest Taiwan, but unstable, especially along the active fault zones. The natural gas as well as the mud and hydraulic fluid in the deep sediment are pushed into the surface layer. In order to investigate the relationship between mud diapir and gas hydrate, we conduct the geophysical and geological methods: using a 38/150 kHz high-frequency echo sounder system to guide and select the sites for mud diapirs, and take 1-3 m gravity core samples. We, then, adopt an up-side-down "headspace" tin-can technique to preserve the gases, and use a gas chromatography to analyze its contents. Oil companies commonly use the method. The first result shows that the existence of methane, ethane, propane and possible other higher hydrocarbon contents in the core samples. The methane is the most abundant gas, up to 1859 parts per million in volume (ppm); the others are not significant, probably due to a leaking in the sampling and transportation. We have reduced the "headspace" in order to preserve more concentrated gases in the second attempt, and the result shows similar. Nonetheless, our results suggest that the gases are probably a mixture of thermogenic and biogenic origin. Due to the existence of higher hydrocarbon contents, we believe that the thermogenic gases are produced in the deep source sediments, while the shallow biogenic methane is mixing with them in the top sediment. In the mud diapir/volcano area, the contents of natural gases are usually higher than that in a flat seafloor. As several high gas values have been founded in the near shore area (e.g., 1604 ppm of C1 plus C2 and C3 found at a water depth of 23 m), we suggest that the 300-3000 m gas hydrate zone is probably in a dynamic balance of which the deep gases are continuously migrating to the BSR and the free gases are being evaporating from this zone. Our data illustrate the potential existence of natural gases in this region; however, we cannot quantify the reserve at this time. Further investigations with a long core and better-improved techniques are needed.
NASA Astrophysics Data System (ADS)
Dill, H. G.; Kaufhold, S.
2018-04-01
The Holocene mud volcano exposed at Totumo (younger than 4150 ± 50 yr BP) lines up together with some other landforms of its kind along the Caribbean Coast in northern Colombia. It currently vents a mud of the silicate-phosphate-bearing sulfur-sodium chloride type. The mud volcanoes evolved in an active continental margin setting of the South American Cordillera with high seismicity and affected by pervasive neotectonic structural disturbances. During the Neogene and Quaternary linear terrigenous shoreline sediments alternating with delta deposits evolved on this mobile crustal segment between the Andes and ancient Precambrian cratons. Meso- to microtidal sedimentary settings during transgression and progradation created meta- to instable sedimentary and petrophysical conditions (e.g. overpressure and gas-bearing bubble sands), favorable for the formation of mud volcanoes, whose lithofacies is subdivided into (1) footwall facies (detritus from metabasic, -pelitic source rocks), (2) mud volcano plus lateral facies (material from deep-seated hydrothermal sources, hydrocarbon plays, and brine reflux from the sea), (3) hanging wall facies, sand characterized by a strong longshore drift. The sedimentary volcanism in the area is characterized by different temperatures of formation: (1) pre-stage (<100 °C) and (2) recent stage (≈25 °C). Heavy (pyroxene, amphibole, epidote-clinozoisite, Fe-Ti silicates and oxides, garnet, alumosilicates, tourmaline, zircon, barite, Fe sulfides and -sulfates), light (Ca sulfates, calcite, quartz, feldspar) and clay minerals (kaolinite, mica, pyrophyllite, chlorite, vermiculite) are efficient tools to determine the source of mud, to subdivide the mud volcano system as to its facies and describe its physical-chemical regime as to the temperature of formation, pH and Eh values. The mud volcano system of Totumo bridges the gap between sedimentary "volcanism" and epithermal hot spring deposits of intermediate to high sulfidation and forms a useful "guide" to hydrocarbon accumulation.
NASA Astrophysics Data System (ADS)
Gilhooly, W. P.; Ruppel, C. D.; Dickens, G. R.; Berg, P.; Macko, S. A.
2010-12-01
Chloride and sulfate pore water analyses were performed on a total of 29 piston and gravity cores collected along center to flank transects across 3 mud volcanoes, which were located on the Louisiana continental slope in Garden Banks (GB425), Green Canyon (CG185), and Mississippi Canyon (MC852). All three sites are known areas of oil and gas discharge. In addition, seepage at GC185 and GB425 supports highly developed chemosynthetic communities, whereas no known communities have been observed at MC852. Comparison of pore water chemistry (sulfur concentrations and sulfur isotope compositions) among these 3 sites provides initial insight about fluid migration processes and advection rates and about the connection between fluid flux and the establishment of chemosynthetic communities. Pore water advection velocities were calculated from chloride profiles using a steady-state one dimensional advection-diffusion model. In general, chloride concentrations increased with depth to more than four times seawater concentrations. Incidences of pore water freshening are likely associated with hydrate dissociation. Chloride profiles show characteristic concave-up shapes at the center of each mud volcano and concave-down shapes along the flanks, a pattern that we previously interpreted and modeled (doi:10.1029/2004GL021909; doi:10.1111/j.1468-8123.2007.00191.x) in terms of seawater recharge-discharge. The depth of the sulfate-methane interface (SMI) shoals toward the center of the mud volcanoes, indicating potentially rapid anaerobic methane oxidation in these areas. Where the SMI is shallow, pore water sulfide S-isotope values are correspondingly elevated (~ +10 ‰) relative to seawater sulfate (δ34S = +21‰) and presumably represent near-quantitative reduction of pore water sulfate at GB425 and MC852. There is no such pattern at GC185. Such differences potentially reflect advection rates, the ages of the fluids, timing of fluid efflux, and differences in their chemistry.
NASA Astrophysics Data System (ADS)
Rice, M. P.
1982-07-01
The design and manufacturing of a solar thermal collector is discussed. The collector has three primary subsystems: concentrator, receiver/fluid loop, and controls. Identical curved reflective columns are utilized in a faceted Fresnel design to support 864 one foot square flat inexpensive second-surface, silvered glass mirrors. The columns are ganged together and rotated through their centers of gravity to provide elevation tracking. The concentrator is supported by a lightweight spaceframe structure which distributes all wind and gravity loads to the base supports. The base of the structure is a track which rotates on wheels mounted on concrete piers. A parallel tube steel heat exchanger is mounted at the concentrator focal area in a well insulated, galvanized steel housing. Two rows of vertical close-packed, staggered tubes connect a mud header and a steam header. Automatic two axis tracking and operational control is provided with a microprocessor based package. Concentrator-mounted shadowbands are the basis for active tracking. A software program provides azimuthal tracking during cloudy periods.
NASA Technical Reports Server (NTRS)
Rice, M. P.
1982-01-01
The design and manufacturing of a solar thermal collector is discussed. The collector has three primary subsystems: concentrator, receiver/fluid loop, and controls. Identical curved reflective columns are utilized in a faceted Fresnel design to support 864 one foot square flat inexpensive second-surface, silvered glass mirrors. The columns are ganged together and rotated through their centers of gravity to provide elevation tracking. The concentrator is supported by a lightweight spaceframe structure which distributes all wind and gravity loads to the base supports. The base of the structure is a track which rotates on wheels mounted on concrete piers. A parallel tube steel heat exchanger is mounted at the concentrator focal area in a well insulated, galvanized steel housing. Two rows of vertical close-packed, staggered tubes connect a mud header and a steam header. Automatic two axis tracking and operational control is provided with a microprocessor based package. Concentrator-mounted shadowbands are the basis for active tracking. A software program provides azimuthal tracking during cloudy periods.
Surface Effect Takeoff and Landing System (SETOLS)
1974-04-01
State-of-the-Art 33 4. Program Tranisfer ~34 5. Future Research 34 6. Current Organizational Contacts and Identification 36 I REFE~RENCES 37 DEFENSE...ability to taxi over water, mud, low tree stumps, and empty and water-filled ditches. The flight tests indicated no significant changes in the...flight Lested from hard--surface runways, turf, water, snow, and fine sand. The aircraft also demonstrated the ability to taxi across mud, low tree
Influence of Internal Waves on Transport by a Gravity Current
NASA Astrophysics Data System (ADS)
Koseff, Jeffrey; Hogg, Charlie; Ouillon, Raphael; Ouellette, Nicholas; Meiburg, Eckart
2017-11-01
Gravity currents moving along the continental slope can be influenced by internal waves shoaling on the slope resulting in mixing between the gravity current and the ambient fluid. Whilst some observations of the potential influence of internal waves on gravity currents have been made, the process has not been studied systematically. We present laboratory experiments, and some initial numerical simulations, in which a gravity current descends down a sloped boundary through a pycnocline at the same time as an internal wave at the pycnocline shoals on the slope. Measurements of the downslope mass flux of the gravity current fluid in cases with different amplitudes of the incident internal wave will be discussed. For the parameter regime considered, the mass flux in the head of the gravity current was found to reduce with increasingly larger incident amplitude waves. This reduction was effectively caused by a ``decapitation'' process whereby the breaking internal wave captures and moves fluid from the head of the gravity current back up the slope. The significance of the impact of the internal waves on gravity current transport, strongly suggests that the local internal wave climate may need to be considered when calculating gravity current transport. The Bob and Norma Street Environmental Fluid Mechanics Laboratory.
Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.
2014-01-01
Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9–33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9–16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9–16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This “updraft” event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.
NASA Astrophysics Data System (ADS)
Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.
2014-01-01
Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9-33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9-16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9-16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This "updraft" event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.
Dense Gravity Currents with Breaking Internal Waves
NASA Astrophysics Data System (ADS)
Tanimoto, Yukinobu; Hogg, Charlie; Ouellette, Nicholas; Koseff, Jeffrey
2017-11-01
Shoaling and breaking internal waves along a pycnocline may lead to mixing and dilution of dense gravity currents, such as cold river inflows into lakes or brine effluent from desalination plants in near-coastal environments. In order to explore the interaction between gravity currents and breaking interfacial waves a series of laboratory experiments was performed in which a sequence of internal waves impinge upon a shelf-slope gravity current. The waves are generated in a two-layer thin-interface ambient water column under a variety of conditions characterizing both the waves and the gravity currents. The mixing of the gravity current is measured through both intrusive (CTD probe) and nonintrusive (Planar-laser inducted fluorescence) techniques. We will present results over a full range of Froude number (characterizing the waves) and Richardson number (characterizing the gravity current) conditions, and will discuss the mechanisms by which the gravity current is mixed into the ambient environment including the role of turbulence in the process. National Science Foundation.
NASA Astrophysics Data System (ADS)
Strom, K.; Tran, D. A.; Dillon, B.
2017-12-01
Predicting the size and settling velocity of mud suspensions under the influence of flocculation is crucial for the accurate prediction of mud movement and deposition in sediment transport modeling of environments such as agricultural streams, large coastal rivers, estuaries, river plumes, boundary currents, and turbidity currents. Yet, collecting accurate and high resolution data on mud flocs is difficult. For example, measurement of flocs with camera systems generally provide the best avenue for preserving floc structure and obtaining accurate information about true floc sizes. However, capturing images of flocs in swirling turbulent flows can be difficult and often limited to suspensions where concentrations are low (< 100 mg/L). As a result, models that account for the influence of flocculation on mud settling velocity are based on sparse data that often present non-congruent functionality in floc size and settling velocity with basic influencers such as suspended sediment concentration. Here we present developments in image acquisition systems and processing methods that allow for measurement of floc size distributions in turbulent suspensions approaching 500 mg/L. At the heart of these developments are the introduction of a simple flow-through cell, modern digital sensor technology, and automated image processing. The combination of these elements allows for high-resolution times series of floc size populations to be measured in turbulent suspensions over a much broader range of suspended sediment concentration than has previously been possible — all without the need to transfer samples to a separate imaging container. We show applications and results from these developments in laboratory experiments and highlight their use in a newly-developed, low-cost, and field-deployable floc camera system.
NASA Astrophysics Data System (ADS)
Suzuki, T.; Kawamura, K.; Ogawa, Y.; Flemings, P. B.; Behrmann, J. H.; John, C. M.; Hirano, N.; Abe, N.
2005-12-01
We collected three m-long piston cores of mud during the Kairei cruise (KR04-08 and KR05-10) of Japan Marine Science and Technology Center in 2004 and 2005 from the NW Pacific between Honshu and Shatsky Rise; aside the Fukahori Knoll and Yukawa Knoll. Another set of mud cores, 234.5 m long, was collected during the JOIDES Resolution cruise (IODP Exp308, site U1322) in 2005 from the Ursa Basin located at the eastern levee of the Mississippi Canyon, northeastern Gulf of Mexico of about 1000 m depth. Our study purpose is to know the flow direction by mud particle arrangement by thin section and scanning electron microscope (SEM) and anisotropy of magnetic susceptibility (AMS) data. The data from the NW Pacific indicate weak preferred orientation from SW to NE, suggesting weak bottom current. This is supported by erosional moat to NE direction around the Fukahori Knoll. In the Gulf of Mexico we can know the flow directions of river plumes, turbidity currents, etc., and we can know whether the flows come from the main entry point in the basin or they are derived from the others of the basin. The other basic features of the core sediments are lithology, sedimentary structures, and porosity, together with paleocurrent analysis.
Morphodynamic Model of Submarine Canyon Incision by Sandblasting
NASA Astrophysics Data System (ADS)
Zhang, L.; Parker, G.; Izumi, N.; Cartigny, M.; Li, T.; Wang, G.
2017-12-01
Submarine canyons are carved by turbidity currents under the deep sea. As opposed to subaerial canyons, the relevant processes are not easy to observe directly. Turbidity currents are bottom-hugging sediment gravity flows of that can incise or deposit on the seafloor to create submarine canyons or fans. The triggers of turbidity currents can be storms, edge waves, internal waves, canyon wall sapping, delta failure, breaching and hyperpycnal flows. The formation and evolution mechanisms of submarine canyons are similar to those of subaerial canyons, but have substantial differences. For example, sandblasting, rather than wear due to colliding gravel clasts is more likely to be the mechanism of bedrock incision. Submarine canyons incise downward, and often develop meander bends and levees within the canyon, so defining "fairways". Here we propose a simple model for canyon incision. The starting point of our model is the Macro Roughness Saltation Abrasion Alluviation model of Zhang et al. [2015], designed for bedrock incision by gravel clasts in mixed bedrock-alluvial rivers. We adapt this formulation to consider sandblasting as a means of wear. We use a layer-averaged model for turbidity current dynamics. The current contains a mixture of mud, which helps drive the flow but which does not cause incision, and sand, which is the agent of incision. We show that the model can successfully model channel downcutting, and indeed illustrate the early formation of net incisional cyclic steps, i.e. upstream-migrating undulations on the bed associated with transcritical (in the Froude sense) flow. These steps can be expected to abet the process of incision.
Inscuteable Regulates the Pins-Mud Spindle Orientation Pathway
Mauser, Jonathon F.; Prehoda, Kenneth E.
2012-01-01
During asymmetric cell division, alignment of the mitotic spindle with the cell polarity axis ensures that the cleavage furrow separates fate determinants into distinct daughter cells. The protein Inscuteable (Insc) is thought to link cell polarity and spindle positioning in diverse systems by binding the polarity protein Bazooka (Baz; aka Par-3) and the spindle orienting protein Partner of Inscuteable (Pins; mPins or LGN in mammals). Here we investigate the mechanism of spindle orientation by the Insc-Pins complex. Previously, we defined two Pins spindle orientation pathways: a complex with Mushroom body defect (Mud; NuMA in mammals) is required for full activity, whereas binding to Discs large (Dlg) is sufficient for partial activity. In the current study, we have examined the role of Inscuteable in mediating downstream Pins-mediated spindle orientation pathways. We find that the Insc-Pins complex requires Gαi for partial activity and that the complex specifically recruits Dlg but not Mud. In vitro competition experiments revealed that Insc and Mud compete for binding to the Pins TPR motifs, while Dlg can form a ternary complex with Insc-Pins. Our results suggest that Insc does not passively couple polarity and spindle orientation but preferentially inhibits the Mud pathway, while allowing the Dlg pathway to remain active. Insc-regulated complex assembly may ensure that the spindle is attached to the cortex (via Dlg) before activation of spindle pulling forces by Dynein/Dynactin (via Mud). PMID:22253744
Mud deposit formation on the open coast of the larger Patos Lagoon-Cassino Beach system
NASA Astrophysics Data System (ADS)
Vinzon, S. B.; Winterwerp, J. C.; Nogueira, R.; de Boer, G. J.
2009-03-01
This paper proposes an explanation of the mud deposits on the inner Shelf of Cassino Beach, South Brazil, by using computational modeling. These mud deposits are mainly formed by sediments delivered from Patos Lagoon, a coastal lagoon connected to the Shelf, next to Cassino Beach. The deposits are characterized by (soft) mud layers of about 1 m thick and are found between the -5 and -20 isobaths. Two hydrodynamic models of the larger Patos Lagoon-Cassino Beach system were calibrated against water elevation measured for a 5 months period, and against currents and salinity measured for a week period. The circulation patterns and water exchange through the mouth were analyzed as a function of local and remote wind effects, and river discharges. The remote wind effect mainly governs the quantity of water exchange with the Lagoon through its effect on mean sea level as a result of Ekman dynamics, while river discharges are important for the salinity of the exchanged water masses. Local winds augment the export-import rates by set-up and set-down within the Lagoon, but their effects are much smaller than those of the remote wind. Currents patterns on the inner Shelf during water outflow revealed a recirculation zone south of the Lagoon, induced by the local geometry and bathymetry of the system. This recirculation zone coincides with observed locations of mud deposition. Water, hence suspended sediment export occurs when remote and local winds are from the N-E, which explains why fine sediment deposits are mainly found south of the Lagoon's breakwater. A sensitivity analysis with the numerical model quantified the contribution of the various mechanisms driving the transport and fate of the fine suspended sediments, i.e. the effects of remote and local wind, of the astronomical tide, of river discharge and fresh-salt water-induced density currents, and of earth rotation. It is concluded that gravitational circulation and earth rotation affects the further dispersion of the deposits largely, whereas the remote wind effect has the largest influence on the amount of sediment released from the Lagoon. It is noted that this paper analyzes the initial deposition patterns induced by current effects only. However, in reality, these deposits are further redistributed over the Shelf by wave effects—these are subject of a next study on the sediment dynamics of the larger Patos Lagoon-Cassino Beach system.
Mud crab ecology encourages site-specific approaches to fishery management
NASA Astrophysics Data System (ADS)
Dumas, P.; Léopold, M.; Frotté, L.; Peignon, C.
2012-01-01
Little is known about the effects of mud crabs population patterns on their exploitation. We used complementary approaches (experimental, fisher-based) to investigate how small-scale variations in density, size and sex-ratio related to the ecology of S. serrata may impact fishing practices in New Caledonia. Crabs were measured/sexed across 9 stations in contrasted mangrove systems between 2007 and 2009. Stations were described and classified in different kinds of mangrove forests (coastal, riverine, and estuarine); vegetation cover was qualitatively described at station scale. Annual catch was used as an indicator of fishing pressure. Middle-scale environmental factors (oceanic influence, vegetation cover) had significant contributions to crab density (GLM, 84.8% of variance), crab size and sex-ratio (< 30%). While small-scale natural factors contributed significantly to population structure, current fishing levels had no impacts on mud crabs. The observed, ecologically-driven heterogeneity of crab resource has strong social implications in the Pacific area, where land tenure system and traditional access rights prevent most fishers from freely selecting their harvest zones. This offers a great opportunity to encourage site-specific management of mud crab fisheries.
NASA Astrophysics Data System (ADS)
Gill, J. B.; Bongiolo, E. M.; Miyazaki, T.; Hamelin, C.; Jutzeler, M.; DeBari, S.; Jonas, A.-S.; Vaglarov, B. S.; Nascimento, L. S.; Yakavonis, M.
2018-04-01
The inorganic portion of tuffaceous mud and mudstone in an oceanic island arc can be mostly volcanic in origin. Consequently, a large volume of submarine volcaniclastic material is as extremely fine-grained as products of subaerial eruptions (<100 µm). Using results of IODP Expedition 350 in the Izu rear arc, we show that such material can accumulate at high rates (12-20 cm/k.y.) within 13 km of the nearest seamount summit and scores of km behind the volcanic front. The geochemistry of bulk, acid-leached mud, and its discrete vitriclasts, shows that >75% of the mud is volcanic, and that most of it was derived from proximal rear arc volcanic sources. It faithfully preserves integrated igneous geochemical information about arc evolution in much the same way that terrigenous shales track the evolution of continental crust. In addition, their high sedimentation rate enables high resolution study of climate cycles, including the effects of Pleistocene glaciation on the behavior of the Kuroshio Current in the Shikoku Basin south of Japan.
Holographic heat current as Noether current
NASA Astrophysics Data System (ADS)
Liu, Hai-Shan; Lü, H.; Pope, C. N.
2017-09-01
We employ the Noether procedure to derive a general formula for the radially conserved heat current in AdS planar black holes with certain transverse and traceless perturbations, for a general class of gravity theories. For Einstein gravity, the general higher-order Lovelock gravities and also a class of Horndeski gravities, we derive the boundary stress tensor and show that the resulting boundary heat current matches precisely the bulk Noether current.
Filling box stratification fed by a gravity current
NASA Astrophysics Data System (ADS)
Hogg, Charlie; Huppert, Herbert; Imberger, Jorg
2012-11-01
Fluids in confined basins can be stratified by the filling box mechanism. The source of dense fluid in geophysical applications, such as a cold river entering a warmer lake, can be a gravity current running over a shallow slope. Filling box models are often, however, based on the dynamics of vertically falling, unconfined, plumes which entrain fluid by a different mechanism to gravity currents on shallow slopes. Laboratory tank experiments of a filling box fed by a gravity current running over a shallow slope were carried out using a dye attenuation technique to investigate the development of the stratification of the ambient. These results demonstrate the differences in the stratification generated by a gravity current compared to that generated by a plume and demonstrate the nature of entrainment into gravity currents on shallow slopes.
Measuring gravity currents in the Chicago River, Chicago, Illinois
Oberg, K.A.; Czuba, J.A.; Johnson, K.K.
2008-01-01
Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current profilers (ADCP) can be used to detect and characterize gravity currents in the field. In order to better understand the formation and evolution of these gravity currents, the U.S. Geological Survey (USGS) has installed ADCPs and other instruments to continuously measure gravity currents in the Chicago River and the North Branch Chicago River. These instruments include stage sensors, thermistor strings, and both upward-looking and horizontal ADCPs. Data loggers and computers installed at gaging stations along the river are used to collect data from these instruments and transmit them to USGS offices. ?? 2008 IEEE.
NASA Astrophysics Data System (ADS)
Nair, Nisha; Pandey, Dhananjai K.
2018-02-01
Interpretation of multichannel seismic reflection data along the Mumbai Offshore Basin (MOB) revealed the tectonic processes that led to the development of sedimentary basins during Cenozoic evolution. Structural interpretation along three selected MCS profiles from MOB revealed seven major sedimentary sequences (∼3.0 s TWT, thick) and the associated complex fault patterns. These stratigraphic sequences are interpreted to host detritus of syn- to post rift events during rift-drift process. The acoustic basement appeared to be faulted with interspaced intrusive bodies. The sections also depicted the presence of slumping of sediments, subsidence, marginal basins, rollover anticlines, mud diapirs etc accompanied by normal to thrust faults related to recent tectonics. Presence of upthrusts in the slope region marks the locations of local compression during collision. Forward gravity modeling constrained with results from seismic and drill results, revealed that the crustal structure beneath the MOB has undergone an extensional type tectonics intruded with intrusive bodies. Results from the seismo-gravity modeling in association with litholog data from drilled wells from the western continental margin of India (WCMI) are presented here.
Circulation-based Modeling of Gravity Currents
NASA Astrophysics Data System (ADS)
Meiburg, E. H.; Borden, Z.
2013-05-01
Atmospheric and oceanic flows driven by predominantly horizontal density differences, such as sea breezes, thunderstorm outflows, powder snow avalanches, and turbidity currents, are frequently modeled as gravity currents. Efforts to develop simplified models of such currents date back to von Karman (1940), who considered a two-dimensional gravity current in an inviscid, irrotational and infinitely deep ambient. Benjamin (1968) presented an alternative model, focusing on the inviscid, irrotational flow past a gravity current in a finite-depth channel. More recently, Shin et al. (2004) proposed a model for gravity currents generated by partial-depth lock releases, considering a control volume that encompasses both fronts. All of the above models, in addition to the conservation of mass and horizontal momentum, invoke Bernoulli's law along some specific streamline in the flow field, in order to obtain a closed system of equations that can be solved for the front velocity as function of the current height. More recent computational investigations based on the Navier-Stokes equations, on the other hand, reproduce the dynamics of gravity currents based on the conservation of mass and momentum alone. We propose that it should therefore be possible to formulate a fundamental gravity current model without invoking Bernoulli's law. The talk will show that the front velocity of gravity currents can indeed be predicted as a function of their height from mass and momentum considerations alone, by considering the evolution of interfacial vorticity. This approach does not require information on the pressure field and therefore avoids the need for an energy closure argument such as those invoked by the earlier models. Predictions by the new theory are shown to be in close agreement with direct numerical simulation results. References Von Karman, T. 1940 The engineer grapples with nonlinear problems, Bull. Am. Math Soc. 46, 615-683. Benjamin, T.B. 1968 Gravity currents and related phenomena, J. Fluid Mech. 31, 209-248. Shin, J.O., Dalziel, S.B. and Linden, P.F. 2004 Gravity currents produced by lock exchange, J. Fluid Mech. 521, 1-34.
The Lusi mud eruption dynamics: constraints from field data.
NASA Astrophysics Data System (ADS)
Mazzini, Adriano; Sciarra, Alessandra; Lupi, Matteo; Mauri, Guillaume; Karyono, Karyono; Husein, Alwi; Aquino, Ida; Ricco, Ciro; Obermann, Anne; Hadi, Soffian
2017-04-01
The Indonesian Lusi eruption has been spewing boiling water, gas, and sediments since the 29th of May 2006. Initially, numerous aligned eruptions sites appeared along the Watukosek fault system that was reactivated after the Yogyakarta earthquake occurring the 27th of May in the Java Island. Since its birth Lusi erupted with a pulsating behavior showing intermittent periods of stronger activity resulting in higher fluids and solid emissions intervals. Since 2010 two active vents are constantly active. We conducted detailed monitoring of such clastic geysering activity and this allowed us to distinguish four distinct phases that follow each other and that reoccur every 30 minutes: (1) regular bubbling activity (constant emission of water, mud breccia, and gas); (2) clastic geysering phase with intense bubbling (consisting in reduced vapor emission and more powerful diffused mud bursting); (3) clastic geysering with mud bursts and intense vapour discharge (typically dense plume that propagates up to 100 m in height); (4) quiescent phase marking the end of the geysering activity (basically no gas emissions or bursts observed). In order to better understand this pulsating behavior and to constrain the mechanisms controlling its activity, we designed a multidisciplinary monitoring of the eruption site combining the deployment of numerous instruments around the crater site. Processing of the collected data reveals the dynamic activity of Lusi's craters. Satellite images show that the location of these vents migrated along a NE-SW direction. This is subparallel to the direction of the Watukosek fault system that is the zone of (left) lateral deformation upon which Lusi developed in 2006. Coupling HR camera images with broadband and short period seismic stations allowed us to describe the seismic signal generated by clastic geysering and to constrain the depth of the source generating the signal. We measure a delay between the seismic (harmonic) record and the associated clastic geyser explosion of approximately 3 s. This, in agreement with previous studies, corresponds to a source located some tens of meters depth inside the conduits. We ascribe the harmonic seismic signal to rise of batches of H2O-CO2-CH4 fluids inside the conduit. Once they approach the water-vapour region the sudden pressure drop triggers flashing and the exsolution of the dissolved CO2 and CH4. In the last part of our study we verified whether the powerful clastic geysering (emitting jets up to 20 m high) may induce local deformation of the mud edifice. During the stronger geysering events we measure an increase and drop of gravity overtime that are related to change of mud density within the feeder conduit. We process continuous camera recordings with a video magnifying tool capable of enhancing small variations in the recorded images. Results highlight that major eruptive events are preceded by a deformation of the mud edifice surrounding the vents. Ongoing studies aim to verify if these events are also captured by the tiltmeter measurements. This study represents a step forward to better understand the activity that characterizes Lusi. Further studies will help to better constrain the reactions and dynamics ongoing inside the conduit.
Wang, Ping; Liu, Dong-Yan
2012-01-01
Performances of two common types of red mud, Bayer red mud and Sintering red mud, were investigated in this research. Their compositions, mechanical properties and microstructure characterization were measured through XRD, TG and SEM analysis. Their shear strength, particle size, density and hydraulic characteristics also had been performed. Huge differences between the basic mineral types of these two kinds of red mud also can be found. The comparison of compositions shows that CaCO3 content in Sintering red mud is higher, Bayer red mud has more hazardous elements such as As, Pb and Hg and both have a high concentration of radioactivity. The micro particle of Bayer red mud is finer and more disperse, but the Sintering red mud has higher shear strength. Combining the TG and hydraulic characteristics analysis, it can be shown that Bayer red mud has higher value of water content and Sintering red mud has higher hydraulic conductivity. The paper then illustrates that Sintering red mud can become the main filling material of supporting structure of red mud stocking yard. Bayer red mud has a high reuse value and also can be used as a mixing material of masonry mortar.
Fake conformal symmetry in unimodular gravity
NASA Astrophysics Data System (ADS)
Oda, Ichiro
2016-08-01
We study Weyl symmetry (local conformal symmetry) in unimodular gravity. It is shown that the Noether currents for both Weyl symmetry and global scale symmetry vanish exactly as in conformally invariant scalar-tensor gravity. We clearly explain why in the class of conformally invariant gravitational theories, the Noether currents vanish by starting with conformally invariant scalar-tensor gravity. Moreover, we comment on both classical and quantum-mechanical equivalences in Einstein's general relativity, conformally invariant scalar-tensor gravity, and the Weyl-transverse gravity. Finally, we discuss the Weyl current in the conformally invariant scalar action and see that it is also vanishing.
NASA Astrophysics Data System (ADS)
Liu, Shifeng; Zeng, Jianmin; Wang, Youbin
2017-10-01
A coating with red mud as an electrolyte additive was applied to 5005 aluminum alloy using plasma electrolytic oxidation (PEO). The phase composition of the coating was investigated using X-ray diffraction. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) was used to determine the microstructure and composition profiles of the coating. The coating/substrate adhesion was determined by scratch testing. The corrosion behaviors of the substrate and coating were evaluated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results indicated that the PEO coating with red mud consisted mainly of α-Al2O3 and γ-Al2O3, with small amounts of Fe2O3, CaCO3, and CaTiO3. The surface of the coating was the color of the red mud. The coating had a uniform thickness of about 80 μm and consisted of two main layers: a 6- μm porous outer layer and a 74- μm dense inner layer, which showed typical metallurgical adhesion (coating/substrate adhesion strength of 59 N). The coating hardness was about 1142 HV, much higher than that of the substrate (60 HV). The corrosion potential E corr and corrosion current density i corr of the coating were estimated to be -0.743 V and 3.85 × 10-6 A cm-2 from the PDP curve in 3.5 wt pct NaCl solution, and the maximum impedance and phase angle of the coating were 11 000 Ω and -67 deg, respectively, based on EIS. PEO coating with red mud improved the surface properties and corrosion resistance of 5005 aluminum alloy. This study also shows a potential method for reusing red mud.
[Peloid therapy. An overview of the empirical status and evidence of mud therapy].
Beer, A-M; Fetaj, S; Lange, U
2013-08-01
Numerous peloids for balneotherapy are currently available but in terms of effects and efficacy therapeutic peat has been studied best. Recent studies revealed that both thermal and physical effects of therapeutic peat are comparable and synergistic. The thermal effects of all types of peat used are approximately the same but chemical effects differ. These results have to been taken into account in future peloid analyses and indications and contraindications of mud therapy have to be reviewed in this respect. Some hypothetical aspects of these chemical effects have to be investigated in future clinical studies but clinical experience with mud therapy allows preliminary conclusions to be drawn. This statement is especially supported by recent molecular investigations. Knowledge about the chemical effects is also necessary for planning, defining and designing clinical studies and patients groups. Exemplarily, the therapeutic use of peat in rheumatic diseases and for fertility treatment will be demonstrated.
Ascent velocity and dynamics of the Fiumicino mud eruption, Rome, Italy
NASA Astrophysics Data System (ADS)
Vona, A.; Giordano, G.; De Benedetti, A. A.; D'Ambrosio, R.; Romano, C.; Manga, M.
2015-08-01
In August 2013 drilling triggered the eruption of mud near the international airport of Fiumicino (Rome, Italy). We monitored the evolution of the eruption and collected samples for laboratory characterization of physicochemical and rheological properties. Over time, muds show a progressive dilution with water; the rheology is typical of pseudoplastic fluids, with a small yield stress that decreases as mud density decreases. The eruption, while not naturally triggered, shares several similarities with natural mud volcanoes, including mud componentry, grain-size distribution, gas discharge, and mud rheology. We use the size of large ballistic fragments ejected from the vent along with mud rheology to compute a minimum ascent velocity of the mud. Computed values are consistent with in situ measurements of gas phase velocities, confirming that the stratigraphic record of mud eruptions can be quantitatively used to infer eruption history and ascent rates and hence to assess (or reassess) mud eruption hazards.
NASA Astrophysics Data System (ADS)
Lee, Hee Jun
2015-12-01
The Huksan Mud Belt (HMB) has been extensively investigated with respect to its source and evolution since the 1980s. Studies on sediment budget or accumulation rates suggested two different origins, Korean and combined Korean and Chinese. However, neither of the suggested origins appears reliable because they were based on insufficient or inaccurate datasets on the basic sedimentological characteristics of the HMB. Although a major mud transport was inferred to be closely associated with either the Korean Coastal Current or the Yellow Sea Warm Current, their physical characters during the Holocene transgression have been rarely hind-casted thus far. The majority of studies on high-resolution seismic stratigraphy along with core log have suggested that the HMB stratigraphy consists of two units divided by an erosional boundary. The lower unit is further divided into two subunits by a subtle discontinuity that is laterally correlated with the erosional boundary. In line with the stratigraphy, the studies theorized that the erosion of the HMB had produced a re-deposited distal lobe, the younger lower subunit. In addition, this lobe was inferred to have prograded rapidly during the relatively short period of 6,500-5,500 yr B.P. Although the time interval of the erosion coincides with the decelerating rise in sea level, the hydrodynamic cause and effect of the erosion remain inexplicable. Therefore, the source and evolution of the HMB continue to be controversial, due largely to poor understanding of the paleo-physical oceanography of the Yellow Sea during the Holocene.
Taniguchi, Kiichiro; Kokuryo, Akihiko; Imano, Takao; Minami, Ryunosuke; Nakagoshi, Hideki; Adachi-Yamada, Takashi
2014-12-20
In standard cell division, the cells undergo karyokinesis and then cytokinesis. Some cells, however, such as cardiomyocytes and hepatocytes, can produce binucleate cells by going through mitosis without cytokinesis. This cytokinesis skipping is thought to be due to the inhibition of cytokinesis machinery such as the central spindle or the contractile ring, but the mechanisms regulating it are unclear. We investigated them by characterizing the binucleation event during development of the Drosophila male accessory gland, in which all cells are binucleate. The accessory gland cells arrested the cell cycle at 50 hours after puparium formation (APF) and in the middle of the pupal stage stopped proliferating for 5 hours. They then restarted the cell cycle and at 55 hours APF entered the M-phase synchronously. At this stage, accessory gland cells binucleated by mitosis without cytokinesis. Binucleating cells displayed the standard karyokinesis progression but also showed unusual features such as a non-round shape, spindle orientation along the apico-basal axis, and poor assembly of the central spindle. Mud, a Drosophila homolog of NuMA, regulated the processes responsible for these three features, the classical isoform Mud(PBD) and the two newly characterized isoforms Mud(L) and Mud(S) regulated them differently: Mud(L) repressed cell rounding, Mud(PBD) and Mud(S) oriented the spindle along the apico-basal axis, and Mud(S) and Mud(L) repressed central spindle assembly. Importantly, overexpression of Mud(S) induced binucleation even in standard proliferating cells such as those in imaginal discs. We characterized the binucleation in the Drosophila male accessory gland and examined mechanisms that regulated unusual morphologies of binucleating cells. We demonstrated that Mud, a microtubule binding protein regulating spindle orientation, was involved in this binucleation. We suggest that atypical functions exerted by three structurally different isoforms of Mud regulate cell rounding, spindle orientation and central spindle assembly in binucleation. We also propose that Mud(S) is a key regulator triggering cytokinesis skipping in binucleation processes.
Van Metre, Peter C.; Wilson, Jennifer T.; Horowitz, Arthur J.; Skrobialowski, Stanley C.; Foreman, William T.; Fuller, Christopher C.; Burkhardt, Mark R.; Elrick, Kent A.; Mahler, Barbara J.; Smith, James J.; Zaugg, Steven D.
2007-01-01
Samples of street mud, suspended and bottom sediment in canals discharging to Lake Ponchartrain, and suspended and bottom sediment in the lake were collected and analyzed for chemical constituents to help evaluate the effects of Hurricanes Katrina and Rita and the subsequent unwatering of New Orleans, Louisiana. The approach used for sampling and analysis of chemical data for the study is presented herein. Radionuclides, major and trace elements, and numerous organic compounds in sediment were analyzed. The organic compounds include organochlorine pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, urban waste indicator compounds, and current-use pesticides. Methods for the analysis of urban waste indicator compounds and current-use pesticides in sediment were developed only recently.
Hassan, Ghassan; Yilbas, B. S.; Said, Syed A. M.; Al-Aqeeli, N.; Matin, Asif
2016-01-01
Mud formed from environmental dust particles in humid ambient air significantly influences the performance of solar harvesting devices. This study examines the characterization of environmental dust particles and the chemo-mechanics of dry mud formed from dust particles. Analytical tools, including scanning electron microscopy, atomic force microscopy, energy dispersive spectroscopy, particle sizing, and X-ray diffraction, are used to characterize dry mud and dust particles. A micro/nano tribometer is used to measure the tangential force and friction coefficient while tensile tests are carried out to assess the binding forces of dry mud pellets. After dry mud is removed, mud residuals on the glass surface are examined and the optical transmittance of the glass is measured. Dust particles include alkaline compounds, which dissolve in water condensate and form a mud solution with high pH (pH = 7.5). The mud solution forms a thin liquid film at the interface of dust particles and surface. Crystals form as the mud solution dries, thus, increasing the adhesion work required to remove dry mud from the surface. Optical transmittance of the glass is reduced after dry mud is removed due to the dry mud residue on the surface. PMID:27445272
Hassan, Ghassan; Yilbas, B S; Said, Syed A M; Al-Aqeeli, N; Matin, Asif
2016-07-22
Mud formed from environmental dust particles in humid ambient air significantly influences the performance of solar harvesting devices. This study examines the characterization of environmental dust particles and the chemo-mechanics of dry mud formed from dust particles. Analytical tools, including scanning electron microscopy, atomic force microscopy, energy dispersive spectroscopy, particle sizing, and X-ray diffraction, are used to characterize dry mud and dust particles. A micro/nano tribometer is used to measure the tangential force and friction coefficient while tensile tests are carried out to assess the binding forces of dry mud pellets. After dry mud is removed, mud residuals on the glass surface are examined and the optical transmittance of the glass is measured. Dust particles include alkaline compounds, which dissolve in water condensate and form a mud solution with high pH (pH = 7.5). The mud solution forms a thin liquid film at the interface of dust particles and surface. Crystals form as the mud solution dries, thus, increasing the adhesion work required to remove dry mud from the surface. Optical transmittance of the glass is reduced after dry mud is removed due to the dry mud residue on the surface.
Waitt, Richard B.
1984-01-01
Newly examined exposures in northern Idaho and Washington show that catastrophic floods from glacial Lake Missoula during late Wisconsin time were repeated, brief jökulhlaups separated by decades of quiet glaciolacustrine and subaerial conditions. Glacial Priest Lake, dammed in the Priest River valley by a tongue of the Purcell trench lobe of the Cordilleran ice sheet, generally accumulated varved mud; the varved mud is sharply interrupted by 14 sand beds deposited by upvalley-running currents. The sand beds are texturally and structurally similar to slackwater sediment in valleys in southern Washington that were backflooded by outbursts from glacial Lake Missoula. Beds of varved mud also accumulated in glacial Lake Spokane (or Columbia?) in Latah Creek valley and elsewhere in northeastern Washington; the mud beds were disrupted, in places violently, during emplacement of each of 16 or more thick flood-gravel beds. This history corroborates evidence from southern Washington that only one graded bed is deposited per flood, refuting a conventional idea that many beds accumulated per flood. The total number of such floodlaid beds in stratigraphic succession near Spokane is at least 28. The mud beds between most of the floodlaid beds in these valleys each consist of between 20 and 55 silt-to-clay varves. Lacustrine environments in northern Idaho and Washington therefore persisted for two to six decades between regularly recurring, colossal floods from glacial Lake Missoula.
Stockpiling and Comprehensive Utilization of Red Mud Research Progress
Liu, Dong-Yan; Wu, Chuan-Sheng
2012-01-01
With increasing production of red mud, the environmental problems caused by it are increasingly serious, and thus the integrated treatment of red mud is imminent. This article provides an overview of the composition and the basic characteristics of red mud. The research progress of safe stockpiling and comprehensive utilization of red mud is summarized. The safe stockpiling of red mud can be divided into two aspects: the design and safe operation of the stocking yard. The comprehensive utilization of red mud can be further divided into three aspects: the effective recycling of components, resource utilization and application in the field of environmental protection. This paper points out that the main focus of previous studies on red mud stockpiling is cost reproduction and land tenure. The recovery of resources from red mud has a high value-added, but low level industrialization. The use of red mud as a building material and filler material is the most effective way to reduce the stockpiling of red mud. Red mud used for environmental remediation materials is a new hotspot and worth promoting for its simple processing and low cost.
An electric current associated with gravity sensing in maize roots
NASA Technical Reports Server (NTRS)
Bjorkman, T.; Leopold, A. C.
1987-01-01
The study of gravisensing would be greatly enhanced if physiological events associated with gravity sensing could be detected separately from subsequent growth processes. This report presents a means to discriminate sensing from the growth processes. By using a vibrating probe, we have found an electric current generated by the gravity sensing region of the root cap of maize (Zea mays cv Merit) in response to gravistimulation. On the upper surface of the root cap, the change from the endogenous current has a density of 0.55 microampere per square centimeter away from gravity. The onset of the current shift has a characteristic of lag of three to four minutes after gravistimulation, which corresponds to the presentation time for gravity sensing in this tissue. A description of the current provides some information about the sensing mechanism, as well as being a valuable means to detect gravity sensing independently of differential growth.
NASA Technical Reports Server (NTRS)
Bjorkman, T.; Leopold, A. C.
1987-01-01
Some characteristics of the gravity sensing mechanism in maize root caps were investigated using a bioelectric current as an indicator of gravity sensing. This technique involves the measurement of a change in the current density which arises at the columella region coincidently with the presentation time. Two inhibitors of auxin transport, triiodobenzoic acid and naphthylphthalamic acid, blocked gravitropic curvature but not the change in current density. Two inhibitors of calmodulin activity, compound 48/80 and calmidazolium, blocked both curvature and gravity-induced current. The results suggest that auxin transport is not a component of gravity sensing in the root cap. By contrast, the results suggest that calmodulin plays an intrinsic role in gravity sensing.
Pozzolanic Activity Assessment of LUSI (LUmpur SIdoarjo) Mud in Semi High Volume Pozzolanic Mortar
Hardjito, Djwantoro; Antoni; Wibowo, Gunadi M.; Christianto, Danny
2012-01-01
LUSI mud obtained from the mud volcano in Sidoarjo, Indonesia, is a viable aluminosilicate material to be utilized as pozzolanic material. LUSI is an abbreviation of the local name of the mud, i.e., Lumpur Sidoarjo, meaning Sidoarjo mud. This paper reports the results of an investigation to assess the pozzolanic activity of LUSI mud, especially in semi high volume pozzolanic mortar. In this case, the amount of mud incorporated is between 30% to 40% of total cementitious material, by mass. The content of SiO2 in the mud is about 30%, whilst the total content of SiO2, Fe2O3 and Al2O3 is more than 70%. Particle size and degree of partial cement replacement by treated LUSI mud affect the compressive strength, the strength activity index (SAI), the rate of pozzolanic activity development, and the workability of mortar incorporating LUSI mud. Manufacturing semi high volume LUSI mud mortar, up to at least 40% cement replacement, is a possibility, especially with a smaller particle size of LUSI mud, less than 63 μm. The use of a larger percentage of cement replacement by LUSI mud does not show any adverse effect on the water demand, as the flow of the fresh mortar increased with the increase of percentage of LUSI mud usage.
Liang, Huipeng; Li, Wenfang; Luo, Qingchun; Liu, Chaolan; Wu, Zhengyun; Zhang, Wenxue
2015-10-01
The community structure of bacteria in aged and aging pit mud, which was judged according to their sensory and physicochemical characteristics, was analysed using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative real-time PCR (qPCR). The phyla Firmicutes, Actinobacteria, Proteobacteria, Synergistetes and Unclassified Bacteria were detected and the fermentative Firmicutes was predominant in both types of pit mud in the PCR-DGGE analysis. Among Firmicutes, Clostridiales was dominant in aged pit mud while Bacillales and Lactobacillales were dominant in aging pit mud. The diversity of bacterial communities in aged pit mud was higher than that in aging pit mud. In the qPCR analysis the abundance of Clostridium IV in aged pit mud was higher than that in aging pit mud and there were significant differences in the quantity of Clostridium IV between aged and aging pit mud of the same cellar (P < 0.05). There were some significant differences in the microbial community structure between aged and aging pit mud. The differences in the quantity of Clostridium IV might be involved in the distinction that the aged pit mud has a strong aroma while the aging pit mud does not. © 2014 Society of Chemical Industry.
Numerical simulation of mud erosion rate in sand-mud alternate layer and comparison with experiment
NASA Astrophysics Data System (ADS)
Yoshida, T.; Yamaguchi, T.; Oyama, H.; Sato, T.
2015-12-01
For gas production from methane hydrates in sand-mud alternate layers, depressurization method is expected as feasible. After methane hydrate is dissociated, gas and water flow in pore space. There is a concern about the erosion of mud surface and it may result in flow blockage that disturbs the gas production. As a part of a Japanese National hydrate research program (MH21, funded by METI), we developed a numerical simulation of water-induced mud erosion in pore-scale sand-mud domains to model such mud erosion. The size of which is of the order of 100 micro meter. Water flow is simulated using a lattice Boltzmann method (LBM) and mud surface is treated as solid boundary with arbitrary shape, which changes with time. Periodic boundary condition is adopted at the domain boundaries, except for the surface of mud layers and the upper side. Shear stress acting on the mud surface is calculated using a momentum-exchange method. Mud layer is eroded when the shear stress exceeds a threshold coined a critical shear stress. In this study, we compared the simulated mud erosion rate with experimental data acquired from an experiment using artificial sand-mud core. As a result, the simulated erosion rate agrees well with that of the experiment.
NASA Technical Reports Server (NTRS)
Komar, Paul D.
1991-01-01
The term mud volcano is applied to a variety of landforms having in common a formation by extrusion of mud from beneath the ground. Although mud is the principal solid material that issues from a mud volcano, there are many examples where clasts up to boulder size are found, sometimes thrown high into the air during an eruption. Other characteristics of mud volcanoes (on Earth) are discussed. The possible presence of mud volcanoes, which are common and widespread on Earth, on Mars is considered.
Linked halokinesis and mud volcanism at the Mercator mud volcano, Gulf of Cadiz
NASA Astrophysics Data System (ADS)
Perez-Garcia, Carolina; Berndt, Christian; Klaeschen, Dirk; Mienert, Jürgen; Haffert, Laura; Depreiter, Davy; Haeckel, Matthias
2011-05-01
Mud volcanoes are seafloor expressions of focused fluid flow that are common in compressional tectonic settings. New high-resolution 3-D seismic data from the Mercator mud volcano (MMV) and an adjacent buried mud volcano (BMV) image the internal structure of the top 800 m of sediment at both mud volcanoes, revealing that both are linked and have been active episodically. The total volumes of extruded mud range between 0.15 and 0.35 km3 and 0.02-0.05 km3 for the MMV and the BMV, respectively. The pore water composition of surface sediment samples suggests that halokinesis has played an important role in the evolution of the mud volcanoes. We propose that erosion of the top of the Vernadsky Ridge that underlies the mud volcanoes activated salt movement, triggering deep migration of fluids, dissolution of salt, and sediment liquefaction and mobilization since the end of the Pliocene. Since beginning of mud volcanism in this area, the mud volcanoes erupted four times while there was only one reactivation of salt tectonics. This implies that there are other mechanisms that trigger mud eruptions. The stratigraphic relationship of mudflows from the MMV and BMV indicates that the BMV was triggered by the MMV eruptions. This may either be caused by loading-induced hydrofracturing within the BMV or due to a common feeder system for both mud volcanoes. This study shows that the mud volcanoes in the El Arraiche mud volcano field are long-lived features that erupt with intervals of several tens of thousands of years.
NASA Astrophysics Data System (ADS)
Liu, Xiting; Li, Anchun; Dong, Jiang; Lu, Jian; Huang, Jie; Wan, Shiming
2018-01-01
In the past decade, the 800 km elongated mud belt off Zhejiang-Fujian coast, East China Sea (ECS), has been extensively studied for understanding the source to sink processes on the East Asian continental margin in the context of the Asian monsoon. However, to better understand the sediment source and dispersal pattern, the existing mineralogical and geochemical data of adjacent river systems, including the Changjiang River (CJR) and local rivers in Zhejiang, Fujian and Taiwan, need to be systematically reviewed. Therefore, various indicators from published literatures for the provenance discrimination in the mud belt have been summarised in this article. The results show that high diversity of clay mineral assemblages in fluvial sediments being supplied into the mud belt, e.g., dominant illite and chlorite in the CJR, absence of smectite in Taiwan rivers, similar amounts of the four clay mineral species in Zhejiang rivers, and dominant kaolinite in Fujian rivers. On heavy mineralogy, the CJR is dominated by dolomite, hornblende, and flaky minerals; and among of them, dolomite is distinctive for the CJR. For geochemical approaches, elemental compositions, combined with strontium and neodymium isotopes, reflect strong provenance control. However, geochemical and mineralogical compositions are found to vary with grain size, and thus extra caution should be taken when using these parameters as provenance indicator to discriminate the marine sediments with variety of grain-size fractions. In addition, pyrrhotite, occurred in fluvial sediments from western Taiwan, has not been found in sediments derived from mainland China, indicating that magnetic parameters could be used to discriminate sediment provenance. The mud belt formed during sea-level highstand, when modern current system in the ECS has been established, resulting in sediments derived from the CJR have been transported southward since 8 ka. In addition, sediment provenances have not been constant since initiation of the mud belt in response to climatic and oceanographic changes during the Holocene, which has been documented by mineral and geochemical signals. Nevertheless significant studies have been carried out, to better understand the formation mechanism for the mud belt and its implications for environmental changes, further studies on sediment provenance throughout the Holocene, in situ observation, and sedimentation dynamical modelling are required.
Renormalization of Einstein gravity through a derivative-dependent field redefinition
NASA Astrophysics Data System (ADS)
Slovick, Brian
2018-01-01
This work explores an alternative solution to the problem of renormalizability in Einstein gravity. In the proposed approach, Einstein gravity is transformed into the renormalizable theory of four-derivative gravity by applying a local field redefinition containing an infinite number of higher derivatives. It is also shown that the current-current amplitude is invariant with the field redefinition, and thus the unitarity of Einstein gravity is preserved.
Mobility of 232Th and 210Po in red mud.
Hegedűs, Miklós; Tóth-Bodrogi, Edit; Jónás, Jácint; Somlai, János; Kovács, Tibor
2018-04-01
The valorization of industrial by-products such as red mud became a tempting opportunity, but the understanding of the risks involved is required for the safe utilization of these products. One of the risks involved are the elevated levels of radionuclides (in the 100-1300 Bq/kg range for both the 238 U and 232 Th decay chains, but usually lower than 1000 Bq/kg, which is the recommended limit for excemption or clearance according to the EU BSS released in 2013) in red mud that can affect human health. There is no satisfactory answer for the utilization of red mud; the main current solution is still almost exclusively disposal into a landfill. For the safe utilization and deposition of red mud, it is important to be able to assess the leaching behaviour of radionuclides. Because there is no commonly accepted measurement protocol for testing the leaching of radionuclides in the EU a combined measurement protocol was made and tested based on heavy metal leaching methods. The leaching features of red mud were studied by methods compliant with the MSZ-21470-50 Hungarian standard, the CEN/TS 14429 standard and the Tessier sequential extraction method for 232 Th and 210 Po. The leached solutions were taken to radiochemical separation followed by spontaneous deposition for Po and electrodeposition for Th. The 332 ± 33 Bq/kg 232 Th content was minimally mobile, 1% became available for distilled water 1% and 6% for Lakanen-Erviö solution; the Tessier extraction showed minimal mobility in the first four steps, while more than 85% remained in the residue. The 210 Po measurements had a severe disturbing effect in many cases, probably due to large amounts of iron present in the red mud, from the 310 ± 12 Bq/kg by aqua regia digestion, distilled water mobilized 23%, while Lakanen-Erviö solution mobilized ∼13%. The proposed protocol is suitable for the analysis of Th and Po leaching behaviour. Copyright © 2018 Elsevier Ltd. All rights reserved.
Cyclic Activity of Mud Volcanoes: Evidences from Trinidad (SE Caribbean)
NASA Astrophysics Data System (ADS)
Deville, E.
2007-12-01
Fluid and solid transfer in mud volcanoes show different phases of activity, including catastrophic events followed by periods of relative quiescence characterized by moderate activity. This can be notably shown by historical data onshore Trinidad. Several authors have evoked a possible link between the frequencies of eruption of some mud volcanoes and seismic activity, but in Trinidad there is no direct correlation between mud eruptions and seisms. It appears that each eruptive mud volcano has its own period of catastrophic activity, and this period is highly variable from one volcano to another. The frequency of activity of mud volcanoes seems essentially controlled by local pressure regime within the sedimentary pile. At the most, a seism can, in some cases, activate an eruption close to its term. The dynamics of expulsion of the mud volcanoes during the quiescence phases has been studied notably from temperature measurements within the mud conduits. The mud temperature is concurrently controlled by, either, the gas flux (endothermic gas depressurizing induces a cooling effect), or by the mud flux (mud is a vector for convective heat transfer). Complex temperature distribution was observed in large conduits and pools. Indeed, especially in the bigger pools, the temperature distribution characterizes convective cells with an upward displacement of mud above the deep outlet, and ring-shaped rolls associated with the burial of the mud on the flanks of the pools. In simple, tube-like shaped, narrow conduits, the temperature is more regular, but we observed different types of profiles, with either downward increasing or decreasing temperatures. If the upward flow of mud would be regular, we should expect increasing temperatures and progressively decreasing gradient with depth within the conduits. However, the variable measured profiles from one place to another, as well as time-variable measured temperatures within the conduits and especially, at the base of the conduits, shows that the fluid flow expelled by the studied mud volcanoes is not constant but highly variable through short time-periods. We notably observed very short time-period cyclic variations with a frequency of about 10 minutes. These high frequencies temperature changes could be related to the dynamics of two-phase flows (gas and mud) through the mud volcano conduits. We also observed locally a significant daily changes of the temperature of the expelled mud which shows also that the mud flux is changing very rapidly from one day to another.
Plumlee, Geoffrey S.; Casadevall, Thomas J.; Wibowo, Handoko T.; Rosenbauer, Robert J.; Johnson, Craig A.; Breit, George N.; Lowers, Heather; Wolf, Ruth E.; Hageman, Philip L.; Goldstein, Harland L.; Anthony, Michael W.; Berry, Cyrus J.; Fey, David L.; Meeker, Gregory P.; Morman, Suzette A.
2008-01-01
On May 29, 2006, mud and gases began erupting unexpectedly from a vent 150 meters away from a hydrocarbon exploration well near Sidoarjo, East Java, Indonesia. The eruption, called the LUSI (Lumpur 'mud'-Sidoarjo) mud volcano, has continued since then at rates as high as 160,000 m3 per day. At the request of the United States Department of State, the U.S. Geological Survey (USGS) has been providing technical assistance to the Indonesian Government on the geological and geochemical aspects of the mud eruption. This report presents initial characterization results of a sample of the mud collected on September 22, 2007, as well as inerpretive findings based on the analytical results. The focus is on characteristics of the mud sample (including the solid and water components of the mud) that may be of potential environmental or human health concern. Characteristics that provide insights into the possible origins of the mud and its contained solids and waters have also been evaluated.
Deep-sea mud in the Pacific Ocean as a potential resource for rare-earth elements
NASA Astrophysics Data System (ADS)
Kato, Yasuhiro; Fujinaga, Koichiro; Nakamura, Kentaro; Takaya, Yutaro; Kitamura, Kenichi; Ohta, Junichiro; Toda, Ryuichi; Nakashima, Takuya; Iwamori, Hikaru
2011-08-01
World demand for rare-earth elements and the metal yttrium--which are crucial for novel electronic equipment and green-energy technologies--is increasing rapidly. Several types of seafloor sediment harbour high concentrations of these elements. However, seafloor sediments have not been regarded as a rare-earth element and yttrium resource, because data on the spatial distribution of these deposits are insufficient. Here, we report measurements of the elemental composition of over 2,000 seafloor sediments, sampled at depth intervals of around one metre, at 78 sites that cover a large part of the Pacific Ocean. We show that deep-sea mud contains high concentrations of rare-earth elements and yttrium at numerous sites throughout the eastern South and central North Pacific. We estimate that an area of just one square kilometre, surrounding one of the sampling sites, could provide one-fifth of the current annual world consumption of these elements. Uptake of rare-earth elements and yttrium by mineral phases such as hydrothermal iron-oxyhydroxides and phillipsite seems to be responsible for their high concentration. We show that rare-earth elements and yttrium are readily recovered from the mud by simple acid leaching, and suggest that deep-sea mud constitutes a highly promising huge resource for these elements.
Development of environmental friendly lost circulation material from banana peel
NASA Astrophysics Data System (ADS)
Sauki, Arina; Hasan, Nur â.Izzati; Naimi, Fardelen Binti Md; Othman, Nur Hidayati
2017-12-01
Loss of expensive mud could lead to major financial problem in executing a drilling project and is one of the biggest problems that need to be tackled during drilling. Synthetic Based Mud (SBM) is the most stable state of the art drilling mud used in current drilling technologies. However, the problem with lost circulation is still inevitable. The focus of this project is to develop a new potential waste material from banana peel in order to combat lost circulation in SBM. Standard industrial Lost Circulation Material (LCM) is used to compare the performance of banana peel as LCM in SBM. The effects of different sizing of banana peels (600 micron, 300 micron and 100 micron) were studied on the rheological and filtration properties of SBM and the bridging performance of banana peel as LCM additive. The tests were conducted using viscometer, HTHP filter press and sand bed tester. Thermal analysis of banana peel was also studied using TGA. According to the results obtained, 300 and 100 micron size of banana peel LCM exhibited an improved bridging performance by 65% as compared to industrial LCM. However, banana peel LCM with the size of 600 micron failed to act as LCM due to the total invasion of mud into the sand bed.
NASA Astrophysics Data System (ADS)
Agustawijaya, Didi Supriadi; Karyadi, Karyadi; Krisnayanti, Baiq Dewi; Sutanto, Sutanto
2017-12-01
The Sidoarjo mudflow in East Java, Indonesia, has been erupting since May 29th, 2006. The eruption has been known as the Lusi (lumpur Sidoarjo), which was previously considered as a remote seismic event consequence, but current geyser-like activities show an association with a geothermal phenomenon. A method of characterizing rare earth elements (REE) is commonly an effective tool for recognizing a geothermal system, and here it is adapted to particularly indicate the environmental origin of the Lusi mud. Results show that the Lusi hot mud is made of a porous smectite structure of a shale rock type, which becomes an ideal tank for trapping the REE, especially the light REE. Volcanic activities seem to be an important influence in the eruption; however, since there is a lack of significant isotopic evidences in the mobilization of the REE during the eruption, the chloride neutral pH water of the Lusi may hardly contain the REE. The moderate Ce and Eu anomalies found in the REE patterns of the mud strongly indicate a sea-floor basin as the most probable environment for the REE fractionation during the sedimentary rock formation, in which the weathering processes of volcanic rock origin enriched the Lusi shale with the REE.
30 CFR 250.1614 - Mud program.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Mud program. 250.1614 Section 250.1614 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS... requirements concerning mud control, mud test and monitoring equipment, mud quantities, and safety precautions...
30 CFR 250.1614 - Mud program.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Mud program. 250.1614 Section 250.1614 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS... requirements concerning mud control, mud test and monitoring equipment, mud quantities, and safety precautions...
30 CFR 250.1614 - Mud program.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Mud program. 250.1614 Section 250.1614 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS... requirements concerning mud control, mud test and monitoring equipment, mud quantities, and safety precautions...
Boyko, Christopher B; Williams, Jason D; Shields, Jeffrey D
2017-12-18
Ghost and mud shrimps in Axiidea and Gebiidea are hosts to parasitic epicaridean isopods, including species in Bopyridae and Ionidae. These isopods can reach high prevalence levels on their mud shrimp hosts and may strongly influence host ecology and biology. Currently, 54 species of bopyrids and eight species of ionids are known to parasitize ghost and mud shrimps. We present new taxonomic data on three species of ionids and ten species of bopyrids (nine previously described and one new to science), as well as on an undescribed species of nematode from an axiidean host. New locality and host records are given for all species. Our analysis of new material and review of museum specimens includes the description of the new species Acrobelione halimedae n. sp. from Austinogebia spinfrons (Haswell, 1881). We also provide an improved definition for the genus Pseudione Kossmann, 1881, based on morphological characters found in both sexes, and resolution of the type species, P. callianassae Kossmann, 1881. In our revision of Pseudione we erect a new genus, Robinione, and placed two species therein: R. overstreeti (Adkison Heard, 1995) and R. brattstroemi (Stuardo, Vega Cespedes, 1986). In addition, two other species are removed from Pseudione: P. compressa (Shiino, 1964) is moved to Ionella Bonnier, 1900, and P. panopei Pearse, 1947 is considered a synonym of Progebiophilus upogebiae (Hay, 1917). Bopyrid isopods represent a large, diverse taxon and our findings help clarify the taxonomy of those species found on ghost and mud shrimps.
Chemical Speciation of Chromium in Drilling Muds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taguchi, Takeyoshi; Yoshii, Mitsuru; Shinoda, Kohzo
2007-02-02
Drilling muds are made of bentonite and other clays, and/or polymers, mixed with water to the desired viscosity. Without the drilling muds, corporations could not drill for oil and gas and we would have hardly any of the fuels and lubricants considered essential for modern industrial civilization. There are hundreds of drilling muds used and some kinds of drilling muds contain chromium. The chemical states of chromium in muds have been studied carefully due to concerns about the environmental influence. However it is difficult to determine the chemical state of chromium in drilling muds directly by conventional analytical methods. Wemore » have studied the chemical form of chromium in drilling muds by using a laboratory XAFS system and a synchrotron facility.« less
Experimental simulation of gravity currents in erodible bed
NASA Astrophysics Data System (ADS)
Bateman, A.; La Roca, M.; Medina, V.
2009-04-01
Gravity currents are commonly met in nature, when a flow of denser fluid moves into a less dense one. A typical example of a gravity current is given by the sea water which flows into the bottom of a river during the summer, in correspondence of the estuary, when the river's discharge attains low values. In this case, dangerous consequences can occur, because of the polluting of the aquifer caused by the salty water. Density currents also occurs in lakes and reservoirs, because of a change in temperature or because a flood, both can produce some environmental impacts that are of interest to the local water Agency of the different countries. Of particular relevance is also the interaction of the gravity current with the movement of the sediments from the bottom of the bed. The international state of the art is particularly concerned with experimental and numerical investigation on gravity currents on fixed and porous bed [1-2-3], while, to the authors' knowledge, the interaction of a gravity current with an erodible bed is still an open field of investigation. In this paper experiments concerning with the propagation of a gravity current over fixed and erodible bed are presented. The experiments, conducted at the laboratory of Hydraulics of the Universitat Politecnica de Catalunya (actually in the Prof. Bateman's blue room), were concerned with a transparent tank 2 m long, 0.2 m wide and 0.3 m deep, partly filled with salty water and partly with fresh water, up to a depth of 0.28 m. The salty water, whose density was in the range 1050
NASA Astrophysics Data System (ADS)
Plumlee, G. S.; Casadevall, T. J.; Wibowo, H. T.; Rosenbauer, R. J.; Johnson, C. A.; Breit, G. N.; Hageman, P. L.; Wolf, R. E.; Morman, S. A.
2009-12-01
On May 29, 2006, mud and gases began erupting from a vent 150 meters away from a gas exploration well near Sidoarjo, East Java, Indonesia. The eruption, called the LUSI mud volcano, has continued at rates as high as 160,000 m3 per day. At the request of the United States Department of State, the U.S. Geological Survey (USGS) has been providing technical assistance to the Indonesian Government on the geological and geochemical aspects of the mud eruption. This paper will present analytical results of mud samples collected in Sept. 2007 and Nov. 2008, and interpretive findings based on the analytical results. The 2007 mud sample contains high proportions of particles that could be ingestible by hand-mouth transmission (~98 vol % <250 microns,), inhalable into the upper respiratory tract (~80 vol % <10 microns), and respirable into the lung alveoli (~ 40 vol % <2.5 microns), so the mud and dust from the dried mud could be readily taken up by exposed individuals. Our results confirm those of a previous study that the levels of potentially toxic heavy metals or metalloids in the mud are low. A complex mixture of organic compounds in the mud is likely derived from petroleum source rocks. Although the 2007 mud sample contains several percent iron sulfides, net acid production tests indicate that enough carbonate material is also present to prevent the mud from becoming acid-generating due to weathering and sulfide oxidation in the near-surface environment. Water derived from settling mud deposits may have the potential to adversely affect the quality of surface- or groundwater sources for drinking water, due to high levels of fluoride, nitrate, iron, manganese, aluminum, sulfate, chloride, and total dissolved solids. The very high nitrate levels in the waters contained within the mud may present a source of nutrients that could enhance algal blooms and resulting adverse impacts such as hypoxia in fresh-water and marine ecosystems into which some of the mud is being discharged. In agreement with previous studies, water separated from the 2007 mud sample is compositionally and isotopically compatible with an origin as sedimentary formation water. The iron disulfide fraction of the mud sample is isotopically light, and likely formed by bacterial sulfate reduction during diagenesis of clay-rich rocks from which the mud was derived. A smaller, isotopically heavy monosulfide fraction likely formed later by thermogenic reduction of formation-water sulfate to sulfide and reaction of the resulting sulfide with reactive iron in the mud. Additional linked earth science and public health studies are needed to more fully understand eruption processes, and the potential environmental and health consequences of the erupting mud, waters, and gases, and of the accumulating mud deposits.
Wilber, R. Jude; Milliman, John D.; Halley, Robert B.
1990-01-01
High-resolution seismic profiles and submersible observations along the leeward slope of western Great Bahama Bank show large-scale export of bank-top sediment and rapid progradation of the slope during the Holocene. A wedge-shaped sequence, up to 90 m thick, is present along most of the slope and consists of predominantly aragonite mud derived from the bank since flooding of the platform 6-8 ka. Total sediment volume of the slope sequence is 40%-80% that of Holocene sediment currently retained on the bank. Maximum rates of vertical accumulation and lateral progradation are 11-15 m/ka and 80-110 m/ka, respectively: 10 to 100 times greater than previously known for periplatform muds. Slope deposition of exported mud during sea-level highs appears to have been a major mechanism for the westward progradation of Great Bahama Bank throughout the Quaternary; this may provide a critical modern analogue for ancient progradational margins.
Fragmented Canopies Control the Regimes of Gravity Current Development
NASA Astrophysics Data System (ADS)
Barcelona, Aina; Serra, Teresa; Colomer, Jordi
2018-03-01
Coastal ecosystems (marine littoral regions, wetlands, and deltas) are regions of high biological productivity. However, they are also one of the world's most threatened ecosystems. Wetlands are characterized by aquatic vegetation adapted to high salinity levels and climatic variations. Wetland canopies buffer these hydrodynamic and atmospheric variations and help retain sediment by reducing current velocity during sea storms or runoff after periods of rain. This work focuses on the effect of the presence of a gap (i.e., nonvegetated zone) parallel to the direction of the main current has on the sedimentation and hydrodynamics of a gravity current. The study aims to (1) address the behavior of a gravity current in a vegetated region compared to one without vegetation (i.e., the gap), (2) determine the effect gap size has on how a gravity current evolves, and 3) determine the effect gap sizes have on the sedimentary rates from a gravity current. Laboratory experiments were carried out in a flume using four different sediment concentrations, four different canopy densities (884, 354, 177, and 0 plants·m-2) and three different gap widths (H/2, H, and 1.5H, where H is the height of the water). This work shows that a gravity current's evolution and its sedimentary rates depend on the fractional volume occupied by the vegetation. While current dynamics in experiments with wider gaps are similar to the nonvegetated case, for smaller gaps the dynamics are closer to the fully vegetated case. Nonetheless, the gravity current exhibits the same behavior in both the vegetated region and the gap.
Ahn, J H; Grant, S B
2007-01-01
In-site measurements of particle size spectra were obtained from three offshore cruises to evaluate the physical consequences of increased sediment transport and deposition offshore which was caused by episodic storm runoff water from the Santa Ana River watershed, a highly urbanised coastal watershed in southern California. Of the total annual runoff discharge to the coastal ocean, 89.2% occurred in the 2003/2004 winter season, and 0.22 Mt of sediment mass was transported during the storm events. The runoff plume at surface taken offshore by cross-shore currents progressed rapid aggregation and sedimentation, while the initially high concentration of suspended sediment discharged from the river outlet was dominated by small particles. Vertical profiles of particle size spectra revealed two separated plumes near the river outlet and turbidity plume along the bottom consisted of an abundance of very fine and dense particles. It would appear to support the theory that even if the storm runoff does not carry a high concentration of sediment being capable of generating negative buoyancy, sediment deposition on the shelf might mobilise in dense, fluid mud transported offshore by gravity. In a coastal pollution context, sediment particle size spectra information may offer potentially useful means of characterising particle-associated pollutants for purposes of source tracking and environmental interpretation.
Facies mosaic in a fiord: Carboniferous-Permian Talchir Formation, India
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bose, P.K.; Mukhopadhyay, G.; Bhattacharya, H.N.
1988-01-01
Facies analysis of the basal 37m of the Carboniferous-Permian Talchir Formation is a glacier-fed bedrock trough in Dudhi nala, Bihar, India, provides insight into the pattern of sedimentation of course gravels in a fiord. Rapid transitions between 11 recognized facies, together with their complex organization, random variability in bed thickness, and differences in clast, shape, size, and composition indicate coalescence of fans developed from numerous point sources bordering the elongated trough. Converging slide masses and lodgment tillites on the slopes flanking the trough give way to sediment gravity flow deposits composed of an array of conglomerates (matrix and clast supportedmore » with normal, inverse of absence of grading), attendant turbidite sands, and prodelta mud. The rheology of the in-trough flows ranged from plastic laminar to fluidal turbulent in response to flow from slope to floor of the trough. Rapid calving of icebergs during the onset of deglaciation established a wave regime at the mouth of the trough and deposited cross-stratified sandstone replete with dripstones. The impact of large dripstones landing triggered turbidity currents. Continued rise in water level led to eventual preservation of the fan complex under onlapping wave-built shoal facies that grade into a sequence of upward-thinning hummocky cross-stratified sandstone beds virtually devoid of dripstones.« less
Kindwall-Keller, Tamila L; Ballen, Karen K
2017-09-01
Hematopoietic stem cell transplant (HSCT) is potentially curative for a wide variety of malignant diseases, including acute and leukemias, lymphoma, and myelodysplasia. Choice of a stem cell donor is dependent on donor availability, donor compatibility and health, recipient disease type, and recipient condition. Current sources of stem cell donation for HSCT are matched sibling donors (MSDs), matched unrelated donors (MUDs), 1-antigen mismatched unrelated donors (MMUDs), haploidentical donors (haplo), and umbilical cord blood (UCB) units. Historically, preferred donors for HSCT have been human leukocyte antigen (HLA)-matched sibling donors; however, only about 30% of U.S. patients will have a MSD available. The majority of patients referred for HSCT will require an alternative donor graft: MUD, MMUD, UCB, or haplo. The likelihood of finding a MUD varies depending on the ethnicity of the recipient. White Caucasians of European descent have the greatest chance of finding a MUD. Chances of finding a MUD are significantly less for African-American or Hispanic recipients due to HLA polymorphisms. Therefore, MMUD, UCB, and haplo donor graft sources expand the donor pool for recipients who do not have a MSD or MUD available. Given the variety of different donor stem cell sources available today, nearly every patient who needs an allogeneic HSCT has a potential donor in 2017. All transplant-eligible patients with hematologic malignancies should be evaluated by a transplant center to determine if HSCT is a viable treatment option for their underlying disease process. The goal of this review is to increase the awareness of oncology practitioners to the availability of alternative donor stem cell transplants for patients with hematologic malignancies. Despite new agents, stem cell transplant remains the only curative therapy for many patients with acute and chronic leukemia, myelodysplasia, and lymphoma. Given the variety of different donor stem cell sources available today, nearly every patient who needs an allogeneic stem cell transplant will have a donor. © AlphaMed Press 2017.
NASA Astrophysics Data System (ADS)
Munoz, R.; Caylor, E.; Yost, C. L.; Drake, C.; Ladwig, J. L.; Myrbo, A.; Howes, T.
2014-12-01
Wild rice (Zizania palustris L.) is an aquatic grass with spiritual and subsistence significance to Native people of the Great Lakes region of North America. Mud Lake (Mashkiigwaagamaag), located on the Fond du Lac Band of Lake Superior Chippewa Reservation in Carlton County, Minnesota, USA, once supported an extensive population of wild rice (manoomin). However, early 20th century attempts to ditch and drain surrounding wetlands for landuse intensification severely altered the natural hydrological system that supports wild rice. Fond du Lac Resource Management (FDLRM) technicians are currently working to increase the wild rice population in Mud Lake. As part of these efforts, this phytolith study was undertaken to better understand how wild rice abundance has fluctuated over the past 400 years, with particular emphasis on the 19th and 20th centuries. Phytoliths are microscopic opal silica plant remains that are incorporated into soils and lake sediments after the plant-parts that contain them decay. Wild rice produces phytolith morphotypes that are unequivocally diagnostic. Mud Lake core MNMN-MUD11-1C-1P-1 (46°43'38.39"N, 92°42'2.45"W) was piston cored by LacCore (National Lacustrine Core Facility) and FDLRM technicians on 24 May 2011. Initial core descriptions, multi-sensor core logging, phytolith sampling and phytolith extractions were completed during the summer of 2014 at LacCore. Wild rice phytolith identification and quantification was conducted on twelve samples using brightfield microscopy at 400x magnification. Wild rice phytolith concentration values ranged from 68 to 2,300 phytoliths/cm3. Wild rice accumulation rates ranged from 9 to 383 phytoliths/ cm2/yr, peaking in 1952 AD. Wild rice abundance in Mud Lake appears to be influenced by a complex set of variables that include anthropogenic disturbance, climatic events and aquatic plant community succession.
Origin of lipid biomarkers in mud volcanoes from the Alboran Sea, western Mediterranean
NASA Astrophysics Data System (ADS)
López-Rodríguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruíz, F.; Comas, M.; Sinninghe Damsté, J. S.
2013-11-01
Mud volcanoes (MVs) are the most prominent indicators of active methane/hydrocarbon venting at the seafloor on both passive and active continental margins. Their occurrence in the Western Mediterranean is patent at the West Alboran Basin, where numerous MVs develop overlaying a major sedimentary depocenter containing overpressured shales. Although some of these MVs have been studied, the detailed biogeochemistry of expelled mud so far has not been examined in detail. This work provides the first results on the composition and origin of organic matter, Anaerobic Oxidation of Methane (AOM) processes and general characteristics on MV dynamics using lipid biomarkers as the main tool. Lipid biomarker analysis was performed on MV expelled material (mud breccias) and interbedded hemipelagic sediments from Perejil, Kalinin and Schneider's Heart MVs located in the northwest margin of the Alboran Sea. The n-alkane-distributions and n-alkane-derived indices (CPI and ACL), in combination with the epimerization degree of hopanes (22S/(22S + 22R)) indicate that all studied mud breccia have a similar biomarker composition consisting of mainly thermally immature organic matter with an admixture of petroleum-derived compounds. This concordant composition indicates that common source strata must feed all three studied MVs. The past or present AOM activity was established using lipid biomarkers specific for anaerobic methanotropic archaea (irregular isoprenoids and DGDs) and the depleted carbon isotope composition (δ13C) of crocetane/phytane. The presence of these lipid biomarkers, together with the low amounts of detected GDGTs, is consistent with the dominance of anaerobic methanotrophs of the ANME-2 over ANME-1, at least in mud breccia from Perejil MVs. In contrast, the scarce presence or lack of these AOM-related lipid biomarkers in sediments from Kalinin and Schneider's Heart MVs, suggest no recent active methane seepage has occurred at these sites. Moreover, the observed methane concentrations support the current activity of Perejil MV, and the very low methane seepage activity in Kalinin and Schneider's Heart MVs.
Tiwari, Aseem K; Bhati-Kushwaha, Himakshi; Kukreja, Pooja; Mishra, Vikash C; Tyagi, Neetu; Sharma, Ashish; Raina, Vimarsh
2015-06-01
With an increase in the number of transplants happening globally, hematopoietic stem cells (HSC) transplantation from matched unrelated donor (MUD) has begun. The increasing trend of MUD transplants across countries has been largely facilitated with the conspicuous growth of volunteer HSC donor noted in the last decade i.e. 8 million HSC donors in 2002 to more than 22 million in 2013 registered in 71 member registries of the Bone Marrow Donor Worldwide (BMDW). Some populations of the world are still very poorly represented in these registries. Since, the chances of successful engraftment and disease free survival are directly proportional to the HLA compatibility between the recipient and the prospective donor, the diversity of the HLA system at the antigenic and allelic level and the heterogeneity of HLA data of the registered donors has a bearing on the probability of finding a volunteer unrelated HSC donor for patients from such populations. In the present study 126 patients were identified suffering from hematological diseases requiring MUD transplant. Their HLA typing was performed and search was done using BMDW database. The search results for these Indian patients in the multinational registry as well as in the Indian Registries were analyzed using mean, range, standard deviation and finally evaluated in terms of probability for finding matched donor (MUD). Total Asian population is only 11 % in the BMDW making it difficult to find a MUD for an Asian patient. The current study supports this, experimentally; revealing that the probability of finding an allele match for an Indian patient in the multinational Human Leukocyte Antigen (HLA) registries is 16 % and a dismal 0.008 % in the Indian registries (donors in Indian registries is just 33,678 as compared to 22.5 million in BMDW). This greatly, emphasizes on enhancing the number of Indian donors in Indian and multi-national registries.
NASA Astrophysics Data System (ADS)
Krask, J. L.; Hein, C. J.; Galy, V.; FitzGerald, D.; Henrique de Fontoura Klein, A.
2017-12-01
Whereas millennial-scale variations in climate forcing drives changes in terrestrial processes, which are in turn directly linked to fluvial sediment loads (e.g., weathering and erosion), the impact of decadal- to centennial- scale climate fluctuations on downstream coastal sedimentation patterns and landscape evolution remains unclear. Specifically, the connection between long-term (decades or more) precipitation seasonality and sediment export from river systems has not been established. This study examines the manner in which sub-millennial-scale fluctuations in precipitation over river catchments may be recorded in coastal progradational sedimentary archives. The 5-km wide Tijucas Strandplain (southern Brazil) formed over the last 5800 years through the rapid reworking of sediment discharged from the Tijucas River in a regime of falling sea level. In an overall regime shift from sand- to mud- dominance (linked to a long-term reduction in wave energy caused by bay shoaling) are nearly 70 distinct transitions between shore-parallel sand- and mud- dominated facies. Bulk organic carbon and terrestrial plant-wax fatty acid stable hydrogen (δD) and carbon (δ13C) isotopic measurements from sediments from select sandy and muddy ridges across the plain reveal that these two sedimentological regimes are geochemically distinct. Specifically, waxes from sediments deposited during periods of sandy progradation had δD values, on average, >10 ‰ higher than those from mud-dominated periods, indicating that these sedimentary units reflect different hydroclimatic conditions within the river drainage basin at the time of deposition. Comparison of plant wax isotopic signatures of river, bay, and beach sediments during the current period of mud-dominated progradation reveals a close correlation with earlier periods of mud deposition within the Tijucas Strandplain. Thus, decadal- to centennial- scale sedimentologic transitions within the plain are interpreted to reflect climate-driven changes in mud export rates, as product of modifications in river basin vegetation and soil formation and erosional processes.
2015-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Shallow- Water Mud Acoustics William L. Siegmann...shallow water over mud sediments and of acoustic detection, localization, and classification of objects buried in mud. OBJECTIVES • Develop...including long-range conveyance of information; detection, localization, and classification of objects buried in mud; and improvement of shallow water
46 CFR 128.450 - Liquid-mud systems.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Liquid-mud systems. 128.450 Section 128.450 Shipping...: EQUIPMENT AND SYSTEMS Design Requirements for Specific Systems § 128.450 Liquid-mud systems. (a) Liquid-mud... this chapter. (b) Tanks for oil-based liquid mud must be fitted with tank vents equipped with flame...
Binding of Vapour-Phase Mercury (Hg0) on Chemically Treated Bauxite Residues (Red Mud)
In this study, Hg capture using red mud, seawater-neutralized red mud, and acid-treated red mud is evaluated and compared to other, more conventional sorbent materials. Red mud (also known as bauxite residue) is a by-product of extracting alumina from ground bauxite ore by treati...
A marine dynamic penetrometer for the determination of sea floor geotechnical properties
NASA Astrophysics Data System (ADS)
Stephan, S.; Kaul, N. E.; Villinger, H. W.
2013-12-01
We present a seafloor lance penetration monitoring system: the Lance Insertion Retardation Meter (LIRmeter). The device can be used to infer geotechnical seafloor properties, such as bearing capacity by monitoring the deceleration of a free-fall penetrating lance. The deceleration record can be furthermore used to estimate mean grain size and mud content of the sea floor as well as total penetration depth. The LIRmeter is contained in a pressure vessel (440 x 110 mm) and equipped with accelerometers of different sensitivities to (i) determine sea floor resistance during penetration and (ii) to generate a depth axis. Typically, measurements are carried out in a pogo style fashion to allow a rapid measurement progress during field campaigns. The LIRmeter is intended to determine sea floor properties on the sole basis of deceleration measurements in order to achieve a mechanically and electronically robust system. Data is sampled at a resolution of 16 bit and at a rate of typically 500 Hz for each channel. The device can either be installed in any type of lance i.e. marine heat flow probes, gravity corers, piston corers or can be used in combination with a purpose built lance as a standalone instrument. It has a usable length of four meters, a total weight of 280 kg in air and can be operated up to full ocean depth (6000m). The bearing capacity of the sea floor is a critical factor for marine engineering projects such as burial of marine cables, pipeline laying and foundations. Knowledge of the mud content can provide constraints for the estimation of hydraulic conductivity. The identification of weak zones along a slope can moreover provide vital information for risk assessment studies. Traditionally, frame based, quasi static Cone Penetration Tests (CPT) or sampling methods like gravity coring are used to conduct these types of investigation. In comparison to established but time consuming and rather costly methods, the LIRmeter is intended (i) for near surface investigations and/or (ii) to complement and connect conventional but isolated CPT measurements in a very efficient and rapid way. We show results from measurements in the North Sea, as well as results of laboratory experiments. During sea trials, the LIRmeter was equipped with an additional CPT sensor, which delivered data for cone (tip) resistance, sleeve friction and pore pressure, thus allowing a direct comparison between results of the acceleration measurements and results from conventional CPT sensors. The laboratory measurements were also carried out using both acceleration and tip resistance sensors. Resulting values show a very good agreement between tip resistance calculated from deceleration data and tip resistance from direct laboratory and field measurements. The influence of sediment type (mainly mud content) will be discussed within the context of laboratory measurements.
30 CFR 250.1614 - Mud program.
Code of Federal Regulations, 2011 CFR
2011-07-01
... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Sulphur Operations § 250.1614... shall comply with requirements concerning mud control, mud test and monitoring equipment, mud quantities...
Linking geochemical processes in mud volcanoes with arsenic mobilization driven by organic matter.
Liu, Chia-Chuan; Kar, Sandeep; Jean, Jiin-Shuh; Wang, Chung-Ho; Lee, Yao-Chang; Sracek, Ondra; Li, Zhaohui; Bundschuh, Jochen; Yang, Huai-Jen; Chen, Chien-Yen
2013-11-15
The present study deals with geochemical characterization of mud fluids and sediments collected from Kunshuiping (KSP), Liyushan (LYS), Wushanting (WST), Sinyangnyuhu (SYNH), Hsiaokunshui (HKS) and Yenshuikeng (YSK) mud volcanoes in southwestern Taiwan. Chemical constituents (cations, anions, trace elements, organic carbon, humic acid, and stable isotopes) in both fluids and mud were analyzed to investigate the geochemical processes and spatial variability among the mud volcanoes under consideration. Analytical results suggested that the anoxic mud volcanic fluids are highly saline, implying connate water as the probable source. The isotopic signature indicated that δ(18)O-rich fluids may be associated with silicate and carbonate mineral released through water-rock interaction, along with dehydration of clay minerals. Considerable amounts of arsenic in mud irrespective of fluid composition suggested possible release through biogeochemical processes in the subsurface environment. Sequential extraction of As from the mud indicated that As was mostly present in organic and sulphidic phases, and adsorbed on amorphous Mn oxyhydroxides. Volcanic mud and fluids are rich in organic matter (in terms of organic carbon), and the presence of humic acid in mud has implications for the binding of arsenic. Functional groups of humic acid also showed variable sources of organic matter among the mud volcanoes being examined. Because arsenate concentration in the mud fluids was found to be independent from geochemical factors, it was considered that organic matter may induce arsenic mobilization through an adsorption/desorption mechanism with humic substances under reducing conditions. Organic matter therefore plays a significant role in the mobility of arsenic in mud volcanoes. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sizemore, H. G.; Prettyman, T. H.; De Sanctis, M. C.; Schmidt, B. E.; Hughson, K.; Chilton, H.; Castillo, J. C.; Platz, T.; Schorghofer, N.; Bland, M. T.; Sori, M.; Buczkowski, D.; Byrne, S.; Landis, M. E.; Fu, R.; Ermakov, A.; Raymond, C. A.; Schwartz, S. J.
2017-12-01
Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to have a deep global cryosphere protected by a thin silicate lag. Gravity science along with data collected by Dawn's Framing Camera (FC), Gamma Ray and Neutron Detector (GRaND), and Visible and Infrared Mapping Spectrometer (VIR-MS) during the primary mission at Ceres have confirmed the existence of a global, silicate-rich cryosphere, and suggest the existence of deeper ice, brine, or mud layers. As such, Ceres' surface morphology has characteristics in common with both Mars and the small icy bodies of the outer solar system. We will summarize the evidence for the existence and global extent of the Cerean cryosphere. We will also discuss the range of morphological features that have been linked to subsurface ice, and highlight outstanding science questions.
NASA Astrophysics Data System (ADS)
Hogg, C. A. R.; Huppert, H. E.; Imberger, J.; Dalziel, S. B.
2014-12-01
Dense gravity currents from river inflows feed fluid into confined basins in lakes. Large inflows can influence temperature profiles in the basins. Existing parameterisations of the circulation and mixing of such inflows are often based on the entrainment of ambient fluid into the underflowing gravity currents. However, recent observations have suggested that uni-directional entrainment into a gravity current does not fully describe the transfer between such gravity currents and the ambient water. Laboratory experiments visualised peeling detrainment from the gravity current occurring when the ambient fluid was stratified. A theoretical model of the observed peeling detrainment was developed to predict the temperature profile in the basin. This new model gives a better approximation of the temperature profile observed in the experiments than the pre-existing entraining model. The model can now be developed such that it integrates into operational models of lake basins.
Study on dealkalization and settling performance of red mud.
Luo, Muxi; Qi, Xuejiao; Zhang, Yurui; Ren, Yufei; Tong, Jiacheng; Chen, Zining; Hou, Yiming; Yeerkebai, Nuerxiate; Wang, Hongtao; Feng, Shijin; Li, Fengting
2017-01-01
At present, the dealkalization and comprehensive utilization of red mud is a worldwide problem. Studies on the settling performance and phase transformation of red mud by HCl, CaO, and H 2 O leaching are limited. In this study, the characteristics of red mud were systematically analyzed. The average sizes of graded and initial red mud were 4.11 and 9.20 μm, respectively. X-ray diffraction (XRD), X-ray fluorescence spectra (XRF), and thermogravimetry-differential scanning calorimetry (TG-DSC) results indicated the different mineralogical phases, composition, and thermal behavior. The addition of HCl could neutralize the alkalization in the red mud slurry, and CaO could replace the Na and K. Notably, the pH of the red mud slurry had no obvious change with the increase in water washing times in a certain pH. Interestingly, soluble Al and Fe were not detected in the HCl-red mud and CaO-red mud. In addition, the settling ratio was used to express the settling performance of the red mud slurry. Their interaction mechanisms were proposed, which may include phase transformation and the changing of the size and surface area. The research provided a better understanding of the phase transformation and settling performance in the treatment of red mud by HCl, CaO, and H 2 O leaching.
The use of red mud as an immobiliser for metal/metalloid-contaminated soil: A review.
Hua, Yumei; Heal, Kate V; Friesl-Hanl, Wolfgang
2017-03-05
This review focuses on the applicability of red mud as an amendment for metal/metalloid-contaminated soil. The varying properties of red muds from different sources are presented as they influence the potentially toxic element (PTE) concentration in amended soil. Experiments conducted worldwide from the laboratory to the field scale are screened and the influencing parameters and processes in soils are highlighted. Overall red mud amendment is likely to contribute to lowering the PTE availability in contaminated soil. This is attributed to the high pH, Fe and Al oxide/oxyhydroxide content of red mud, especially hematite, boehmite, gibbsite and cancrinite phases involved in immobilising metals/metalloids. In most cases red mud amendment resulted in a lowering of metal concentrations in plants. Bacterial activity was intensified in red mud-amended contaminated soil, suggesting the toxicity from PTEs was reduced by red mud, as well as indirect effects due to changes in soil properties. Besides positive effects of red mud amendment, negative effects may also appear (e.g. increased mobility of As, Cu) which require site-specific risk assessments. Red mud remediation of metal/metalloid contaminated sites has the potential benefit of reducing red mud storage and associated problems. Copyright © 2016 Elsevier B.V. All rights reserved.
Data on cost analysis of drilling mud displacement during drilling operation.
Okoro, Emeka Emmanuel; Dosunmu, Adewale; Iyuke, Sunny E
2018-08-01
The focus of this research was to present a data article for analyzing the cost of displacing a drilling fluid during the drilling operation. The cost of conventional Spud, KCl and Pseudo Oil base (POBM) muds used in drilling oil and gas wells are compared with that of a Reversible Invert Emulsion Mud. The cost analysis is limited to three sections for optimum and effective Comparison. To optimize drilling operations, it is important that we specify the yardstick by which drilling performance is measured. The most relevant yardstick is the cost per foot drilled. The data have shown that the prices for drilling mud systems are a function of the mud system formulation cost for that particular mud weight and maintenance per day. These costs for different mud systems and depend on the base fluid. The Reversible invert emulsion drilling fluid, eliminates the cost acquired in displacing Pseudo Oil Based mud (POBM) from the well, possible formation damage (permeability impairment) resulting from the use of viscous pill in displacing the POBM from the wellbore, and also eliminates the risk of taking a kick during mud change-over. With this reversible mud system, the costs of special fluids that are rarely applied for the well-completion purpose (cleaning of thick mud filter cake) may be reduced to the barest minimum.
The JPL Mars gravity field, Mars50c, based upon Viking and Mariner 9 Doppler tracking data
NASA Technical Reports Server (NTRS)
Konopliv, Alexander S.; Sjogren, William L.
1995-01-01
This report summarizes the current JPL efforts of generating a Mars gravity field from Viking 1 and 2 and Mariner 9 Doppler tracking data. The Mars 50c solution is a complete gravity field to degree and order 50 with solutions as well for the gravitational mass of Mars, Phobos, and Deimos. The constants and models used to obtain the solution are given and the method for determining the gravity field is presented. The gravity field is compared to the best current gravity GMM1 of Goddard Space Flight Center.
Influence of internal waves on the dispersion and transport of inclined gravity currents
NASA Astrophysics Data System (ADS)
Hogg, C. A. R.; Pietrasz, V. B.; Ouellette, N. T.; Koseff, J. R.
2016-02-01
Brine discharge from desalination facilities presents environmental risks, particularly to benthic organisms. High concentrations of salt and chemical additives, which can be toxic to local ecosystems, are typically mitigated by dilution close to the source. Our laboratory experiments investigate how breaking internal tides can help to dilute gravity currents caused by desalination effluents and direct them away from the benthic layer. In laboratory experiments, internal waves at the pycnocline of an ambient stratification were directed towards a sloping shelf, down which ran a gravity current. The breaking internal waves were seen to increase the proportion of the fluid from the gravity current diverted away from the slope into an intrusion along the pycnocline. In a parametric study, increasing the amplitude of the internal wave was seen to increase the amount of dense fluid in the pycnocline intrusion. The amplitude required to divert the gravity current into the intrusion compares well with an analytical theory that equates the incident energy in the internal wave to the potential energy required to dilute the gravity current. These experimental results suggest that sites of breaking internal waves may be good sites for effluent disposal. Effluent diverted into the intrusion avoids the ecologically sensitive benthic layer.
Feigl, Viktória; Ujaczki, Éva; Vaszita, Emese; Molnár, Mónika
2017-10-01
Red mud can be applied as soil ameliorant to acidic, sandy and micronutrient deficient soils. There are still knowledge gaps regarding the effects of red mud on the soil microbial community. The Biolog EcoPlate technique is a promising tool for community level physiological profiling. This study presents a detailed evaluation of Biolog EcoPlate data from two case studies. In experiment "A" red mud from Ajka (Hungary) was mixed into acidic sandy soil in soil microcosms at 5-50 w/w%. In experiement "B" red mud soil mixture was mixed into low quality subsoil in a field experiment at 5-50 w/w%. According to average well color development, substrate average well color development and substrate richness 5-20% red mud increased the microbial activity of the acidic sandy soil over the short term, but the effect did not last for 10months. Shannon diversity index showed that red mud at up to 20% did not change microbial diversity over the short term, but the diversity decreased by the 10th month. 30-50% red mud had deteriorating effect on the soil microflora. 5-20% red mud soil mixture in the low quality subsoil had a long lasting enhancing effect on the microbial community based on all Biolog EcoPlate parameters. However, 50% red mud soil mixture caused a decrease in diversity and substrate richness. With the Biolog EcoPlate we were able to monitor the changes of the microbial community in red mud affected soils and to assess the amount of red mud and red mud soil mixture applicable for soil treatment in these cases. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Hogg, Charlie; Dalziel, Stuart; Huppert, Herbert; Imberger, Jorg; Department of Applied Mathematics; Theoretical Physics Team; CentreWater Research Team
2014-11-01
Dense gravity currents feed fluid into confined basins in lakes, the oceans and many industrial applications. Existing models of the circulation and mixing in such basins are often based on the currents entraining ambient fluid. However, recent observations have suggested that uni-directional entrainment into a gravity current does not fully describe the mixing in such currents. Laboratory experiments were carried out which visualised peeling detrainment from the gravity current occurring when the ambient fluid was stratified. A theoretical model of the observed peeling detrainment was developed to predict the stratification in the basin. This new model gives a better approximation of the stratification observed in the experiments than the pre-existing entraining model. The model can now be developed such that it integrates into operational models of lakes.
Stratified flows in complex terrain
NASA Astrophysics Data System (ADS)
Retallack, Charles
The focus of this dissertation is the study of stratified atmospheric flows in the presence of complex terrain. Two large-scale field study campaigns were carried out, each with a focus on a specific archetypal terrain. Each field study involved the utilization of remote and in-situ atmospheric monitoring devices to collect experimental data. The first of the two field studies focused on pollution transport mechanisms near an escarpment. The analysis aimed to determine the combined effect of the escarpment and ambient density stratification on the flow and aerosol pollution transport. It was found that under specific atmospheric conditions, the escarpment prompted the channeling, down-mixing, and trapping of aerosol pollutant plumes. The objective of the second field campaign was the study of stratified flows in a mountain valley. Analysis revealed that buoyancy driven katabatic currents originating on the surrounding valley slopes created a scenario in which a down-slope gravity current transitioned into an intrusive gravity current. The intrusive gravity current propagated near the interface of a density stratified lower ambient layer and a non-stratified upper ambient layer. A combination of shallow water theory and energy arguments is used to produce a model for the propagation of a gravity current moving along the interface of a homogeneous ambient layer and a linearly stratified layer. It is found that the gravity current propagating entirely within the homogeneous layer travels at the greatest speed. As the relative density of the gravity current is increased, the gravity current begins to slump below the interface of the two layers and the propagation speed decreases.
Experimental Study on Application of Boron Mud Secondary Resource to Oxidized Pellets Production
NASA Astrophysics Data System (ADS)
Fu, Xiao-Jiao; Chu, Man-Sheng; Zhao, Jia-Qi; Chen, Shuang-Yin; Liu, Zheng-Gen; Wang, Si-Yuan
2017-07-01
In order to realize comprehensive and massive treatment of boron mud secondary resource, fundamental study on boron mud applied to oxidized pellets production as additive was carried out in the paper under laboratory conditions. The effects of boron mud on the performance of oxidized pellets were investigated systemically, and boron mud was combined with other boron-rich material innovatively. The results showed that, within certain limits, boron mud can improve properties of oxidized pellets. The bentonite content decreased to 0.3 % when adding 1.0 % boron mud additive and the pellets met blast furnace requirements. With the combination additive content 0.8 %, bentonite content can be further decreased to 0.2 %, and the pellets properties were better than base pellet. Therefore, it was an effective way to reduce environmental pollution and optimize blast furnace operation by developing boron mud secondary resource as pellets additive.
Acoustical Properties of Mud Sediments
2015-09-30
Acoustical Properties of Mud Sediments Allan D. Pierce Boston University 399 Quaker Meeting House Road P. O. Box 339 East Sandwich, MA 03537...shallow-ocean mud sediments. Other goals are to assess prior data relating to the acoustic properties of mud and to provide guidance in the...development and interpretation of experiments. A related goal is to construct models that will guide inversion techniques for inferring properties of mud
NASA Astrophysics Data System (ADS)
Lesourd, S.; Lesueur, P.; Brun-Cottan, J. C.; Garnaud, S.; Poupinet, N.
2003-09-01
Seasonal variations in the sedimentary regime in the mouth of the Seine river, a macrotidal estuary, are described for a 3-year period. The aim of this study is to characterize and to understand the main governing mechanisms, using data from more than a thousand of superficial sediment grab samples or box cores gathered throughout the study period. Analyses of lithofacies and rheological properties were carried out. The distribution of sediments is governed by seasonal meteorological variations. The surface covered by mud reaches a maximum (40% of the total mouth area) during winter. After the winter, the soft mud deposits are progressively redistributed throughout the whole estuary area and onto the shelf. During the lowest freshwater flow at the end of summer, the fine-grained sediments cover less than 20% of the river mouth area. These seasonal variations mainly depend on the river discharge intensity, but are also linked to wave activity. In the study area, the amount of fine-grained deposits after high river flow periods depends on (1) volume of mud erodable within the estuary, (2) the duration of the flood tidal influx, and (3) the duration preceding the particular annual high river flow. During the last decades, filling of the estuary upstream from Honfleur has led to a downstream shift of the fine-grained sediment deposition area; following this, the present-day mud deposition area is in the open part of the estuary, in the subtidal shallow area. Subsequently, fresh mud deposits undergo intense hydrodynamical and meteorological effects, and are partly reworked by waves and tidal currents effects. In this study, it is shown that the behaviour of suspended matter and of superficial sediments is strongly influenced by short but intense events including high river flows and gales.
NASA Astrophysics Data System (ADS)
Asp, Nils Edvin; Gomes, Vando José Costa; Ogston, Andrea; Borges, José Carlos Corrêa; Nittrouer, Charles Albert
2016-02-01
The tide-dominated eastern sector of the Brazilian Amazonian coast includes large mangrove areas and several estuaries, including the estuary associated with the Urumajó River. There, the dynamics of suspended sediments and delivery mechanisms for mud to the tidal flats and mangroves are complex and were investigated in this study. Four longitudinal measuring campaigns were carried out, encompassing spring/neap tides and dry/rainy seasons. During spring tides, water levels were measured simultaneously at 5 points along the estuary. Currents, salinity, and suspended sediment concentrations (SSCs) were measured over the tidal cycle in a cross section at the middle sector of the estuary. Results show a marked turbidity maximum zone (TMZ) during the rainy season, with a 4-km upstream displacement from neap to spring tide. During dry season, the TMZ was conspicuous only during neap tide and dislocated about 5 km upstream and was substantially less apparent in comparison to that observed during rainy season. The results show that mud is being concentrated in the channel associated with the TMZ especially during the rainy season. At this time, a substantial amount of the mud is washed out from mangroves to the estuarine channel and hydrodynamic/salinity conditions for TMZ formation are optimal. As expected, transport to the mangrove flats is most effective during spring tide and substantially reduced at neap tide, when mangroves are not being flooded. During the dry season, mud is resuspended from the bed in the TMZ sector and is a source of sediment delivered to the tidal flats and mangroves. The seasonal variation of the sediments on the seabed is in agreement with the variation of suspended sediments as well.
ERIC Educational Resources Information Center
Blanck, Harvey F.
2012-01-01
Naturally occurring gravity currents include events such as air flowing through an open front door, a volcanic eruption's pyroclastic flow down a mountainside, and the spread of the Bhopal disaster's methyl isocyanate gas. Gravity currents typically have a small height-to-distance ratio. Plastic models were designed and constructed with a…
Hu, Xiaolong; Du, Hai; Ren, Cong
2016-01-01
Fermentation pit mud, an important reservoir of diverse anaerobic microorganisms, is essential for Chinese strong-aroma liquor production. Pit mud quality, according to its sensory characteristics, can be divided into three grades: degraded, normal, and high quality. However, the relationship between pit mud microbial community and pit mud quality is poorly understood, as are microbial associations within the pit mud ecosystem. Here, microbial communities at these grades were compared using Illumina MiSeq sequencing of the variable region V4 of the 16S rRNA gene. Our results revealed that the pit mud microbial community was correlated with its quality and environmental factors. Species richness, biodiversity, and relative and/or absolute abundances of Clostridia, Clostridium kluyveri, Bacteroidia, and Methanobacteria significantly increased, with corresponding increases in levels of pH, NH4+, and available phosphorus, from degraded to high-quality pit muds, while levels of Lactobacillus, dissolved organic carbon, and lactate significantly decreased, with normal samples in between. Furthermore, 271 pairs of significant and robust correlations (cooccurrence and negative) were identified from 76 genera using network analysis. Thirteen hubs of cooccurrence patterns, mainly under the Clostridia, Bacteroidia, Methanobacteria, and Methanomicrobia, may play important roles in pit mud ecosystem stability, which may be destroyed with rapidly increased levels of lactic acid bacteria (Lactobacillus, Pediococcus, and Streptococcus). This study may help clarify the relationships among microbial community, environmental conditions, and pit mud quality, allow the improvement of pit mud quality by using bioaugmentation and controlling environmental factors, and shed more light on the ecological rules guiding community assembly in pit mud. PMID:26896127
Dewey, Evan B.; Sanchez, Desiree; Johnston, Christopher A.
2015-01-01
SUMMARY Multicellular animals have evolved conserved signaling pathways that translate cell polarity cues into mitotic spindle positioning to control the orientation of cell division within complex tissue structures. These oriented cell divisions are essential for the development of cell diversity and the maintenance of tissue homeostasis. Despite intense efforts, the molecular mechanisms that control spindle orientation remain incompletely defined. Here we describe a role for the Hippo (Hpo) kinase complex in promoting Partner of Inscuteable (Pins)-mediated spindle orientation. Knockdown of Hpo, Salvador (Sav), or Warts (Wts) each result in a partial loss of spindle orientation, a phenotype previously described following loss of the Pins-binding protein Mushroom body defect (Mud). Similar to orthologs spanning yeast to mammals, Wts kinase localizes to mitotic spindle poles, a prominent site of Mud localization. Wts directly phosphorylates Mud in vitro within its C-terminal coiled-coil domain. This Mud coiled-coil domain directly binds the adjacent Pins-binding domain to dampen the Pins/Mud interaction, and Wts-mediated phosphorylation uncouples this intramolecular Mud interaction. Loss of Wts prevents cortical Pins/Mud association without affecting Mud accumulation at spindle poles, suggesting phosphorylation acts as a molecular switch to specifically activate cortical Mud function. Finally, loss of Wts in Drosophila imaginal disc epithelial cells results in diminished cortical Mud and defective planar spindle orientation. Our results provide new insights into the molecular basis for dynamic regulation of the cortical Pins/Mud spindle positioning complex and highlight a novel link with an essential, evolutionarily-conserved cell proliferation pathway. PMID:26592339
Dewey, Evan B; Sanchez, Desiree; Johnston, Christopher A
2015-11-02
Multicellular animals have evolved conserved signaling pathways that translate cell polarity cues into mitotic spindle positioning to control the orientation of cell division within complex tissue structures. These oriented cell divisions are essential for the development of cell diversity and the maintenance of tissue homeostasis. Despite intense efforts, the molecular mechanisms that control spindle orientation remain incompletely defined. Here, we describe a role for the Hippo (Hpo) kinase complex in promoting Partner of Inscuteable (Pins)-mediated spindle orientation. Knockdown of Hpo, Salvador (Sav), or Warts (Wts) each result in a partial loss of spindle orientation, a phenotype previously described following loss of the Pins-binding protein Mushroom body defect (Mud). Similar to orthologs spanning yeast to mammals, Wts kinase localizes to mitotic spindle poles, a prominent site of Mud localization. Wts directly phosphorylates Mud in vitro within its C-terminal coiled-coil domain. This Mud coiled-coil domain directly binds the adjacent Pins-binding domain to dampen the Pins/Mud interaction, and Wts-mediated phosphorylation uncouples this intramolecular Mud interaction. Loss of Wts prevents cortical Pins/Mud association without affecting Mud accumulation at spindle poles, suggesting phosphorylation acts as a molecular switch to specifically activate cortical Mud function. Finally, loss of Wts in Drosophila imaginal disc epithelial cells results in diminished cortical Mud and defective planar spindle orientation. Our results provide new insights into the molecular basis for dynamic regulation of the cortical Pins/Mud spindle positioning complex and highlight a novel link with an essential, evolutionarily conserved cell proliferation pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Golding, Madeleine J.; Huppert, Herbert E.; Neufeld, Jerome A.
2013-03-01
The effects of capillary forces on the propagation of two-phase, constant-flux gravity currents in a porous medium are studied analytically and numerically in an axisymmetric geometry. The fluid within a two-phase current generally only partially saturates the pore space it invades. For long, thin currents, the saturation distribution is set by the vertical balance between gravitational and capillary forces. The capillary pressure and relative permeability of the fluid in the current depend on this saturation. The action of capillary forces reduces the average saturation, thereby decreasing the relative permeability throughout the current. This results in a thicker current, which provides a steeper gradient to drive flow, and a more blunt-nose profile. The relative strength of gravity and capillary forces remains constant within a two-phase gravity current fed by a constant flux and spreading radially, due to mass conservation. For this reason, we use an axisymmetric representation of the framework developed by Golding et al. ["Two-phase gravity currents in porous media," J. Fluid Mech. 678, 248-270 (2011)], 10.1017/jfm.2011.110, to investigate the effect on propagation of varying the magnitude of capillary forces and the pore-size distribution. Scaling analysis indicates that axisymmetric two-phase gravity currents fed by a constant flux propagate like t1/2, similar to their single-phase counterparts [S. Lyle, H. E. Huppert, M. Hallworth, M. Bickle, and A. Chadwick, "Axisymmetric gravity currents in a porous medium," J. Fluid Mech. 543, 293-302 (2005)], 10.1017/S0022112005006713, with the effects of capillary forces encapsulated in the constant of proportionality. As a practical application of our new concepts and quantitative evaluations, we discuss the implications of our results for the process of carbon dioxide (CO2) sequestration, during which gravity currents consisting of supercritical CO2 propagate in rock saturated with aqueous brine. We apply our two-phase model including capillary forces to quantitatively assess seismic images of CO2 spreading at Sleipner underneath the North Sea.
The Onset of Channelling in a Fluidized Mud Layer
NASA Astrophysics Data System (ADS)
Papanicolaou, T.; Tsakiris, A. G.; Billing, B. M.
2012-12-01
Fluidization of a soil occurs when the drag force exerted on the soil grains by upwelling water equals the submerged weight of the soil grains, hence reducing the effective (or contact) stress between the soil grains to zero. In nature, fluidization is commonly encountered in localized portions of highly saturated mud layers found in tidal flats, estuaries and lakes, where upward flow is initiated by significant pore water pressure gradients triggered by wave or tidal action. The water propagates through the fluidized mud layer by forming channels (or vents), carrying the fluidized mud to the surface and forming mud volcano structures. The presence of these fluidization channels alters the mud layer structure with implications on its hydraulic and geotechnical properties, such as the hydraulic conductivity. Despite the importance of these channels, the conditions that lead to their formation and their effects on the mud layer structure still remain poorly documented. The present study couples experimental and theoretical methods aimed at quantifying the conditions, under which fluidization of a saturated mud layer is accompanied by the formation of channels, and assessing the effects of channeling on the mud layer structure. Fluidization and channel formation in a mud layer were reproduced in the laboratory using a carefully designed fluidization column attached to a pressurized vessel (plenum). To eliminate any effects of the material, the mud was produced from pure kaolin clay and deionized water. Local porosity measurements along the mud layer prior, during and after fluidization were conducted using an Americium-241 gamma source placed on a fully automated carriage. Different water inflow rates, q, were applied to the base of the mud layer and the plenum pressure was monitored throughout the experiment. These experiments revealed that for high q values, a single vertical channel formed and erupted at the center of the fluidization column. Instead for low q values, the experiments suggested that a channel network formed within the mud layer leading to the eruption of multiple channels on the mud layer surface. The gamma source measurements captured quantitatively the porosity increase as the channel formed. The experiments were complemented with a theoretical analysis using the two-phase, flow mass and momentum governing equations. This analysis aims to establish a relation between the applied pressure, the fluid velocity and the local porosity of mud during the formation of the channels.
Acute and physical effects of water-based drilling mud in the marine copepod Calanus finmarchicus.
Farkas, Julia; Yvonne Bådsvik, Camilla; Altin, Dag; Nordtug, Trond; Olsen, Anders Johny; Hansen, Bjørn Henrik
2017-01-01
The aim of this study was to investigate impacts of fine particulate fraction of a commonly used barite-containing drilling mud on the pelagic filter feeding copepod Calanus finmarchicus. The results show that the tested drilling mud had a low acute toxicity on C. finmarchicus (LC50 > 320 mg/L) and that the observed toxicity was likely caused by dissolved constituents in the mud and not the particle phase containing the weighting agent barite. Further, animals were exposed to drilling mud at a concentration of 10 mg/L for 168 hr followed by a 100 hr recovery phase. A rapid uptake of drilling mud particles was observed, while the excretion was slow and incomplete even after 100 hr recovery in clean seawater. The uptake of drilling mud particles caused a significant increase in sinking velocity of copepods, indicating that uptake of drilling mud particles affected their buoyancy. Long-term exposure to low concentrations of drilling mud could therefore cause physical effects such as impacts on the animal's buoyancy which may affect the energy budget of the copepods.
Comparison of Copper Scavenging Capacity between Two Different Red Mud Types
Ma, Yingqun; Si, Chunhua; Lin, Chuxia
2012-01-01
A batch experiment was conducted to compare the Cu scavenging capacity between two different red mud types: the first one was a highly basic red mud derived from a combined sintering and Bayer process, and the second one was a seawater-neutralized red mud derived from the Bayer process. The first red mud contained substantial amounts of CaCO3, which, in combination with the high OH− activity, favored the immobilization of water-borne Cu through massive formation of atacamite. In comparison, the seawater-neutralized red mud had a lower pH and was dominated by boehmite, which was likely to play a significant role in Cu adsorption. Overall, it appears that Cu was more tightly retained by the CaCO3-dominated red mud than the boehmite-dominated red mud. It is concluded that the heterogeneity of red mud has marked influences on its capacity to immobilize water-borne Cu and maintain the long-term stability of the immobilized Cu species. The research findings obtained from this study have implications for the development of Cu immobilization technology by using appropriate waste materials generated from the aluminium industry.
The effects of drilling muds on marine invertebrate larvae and adults
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raimondi, P.T.; Barnett, A.M.; Krause, P.R.
1997-06-01
A series of laboratory experiments tested the effects of drilling muds from an active platform off southern California on larvae and adults of marine invertebrates. Red abalone (Haliotis rufescens) were used to determine effects of drilling muds on fertilization, early development, survivorship, and settlement, and experiments on adult brown cup corals (Paracyathus stearnsii) tested effects on adult survivorship, viability, and tissue loss. Exposures to drilling muds did not have an effect on abalone fertilization or early development. However, several exposures to drilling muds resulted in weak, but significant, positive effects of drilling muds on settlement of competent larvae. In contrast,more » settlement of red abalone larvae on natural coralline algal crusts decreased with increasing concentrations of drilling muds. This suggests that drilling muds affect either the abalone`s ability to detect natural settlement inducers, or they affect the inducer itself. Exposure of brown cup corals to concentrations of drilling muds adversely impacted their survivorship and viability. These effects were likely caused by increased tissue mortality of the coral polyps.« less
Antimicrobial Activity of Bacillus Persicus 24-DSM Isolated from Dead Sea Mud.
Al-Karablieh, Nehaya
2017-01-01
Dead Sea is a hypersaline lake with 34% salinity, gains its name due to the absence of any living macroscopic creatures. Despite the extreme hypersaline environment, it is a unique ecosystem for various halophilic microorganisms adapted to this environment. Halophilic microorganisms are known for various potential biotechnological applications, the purpose of the current research is isolation and screening of halophilic bacteria from Dead Sea mud for potential antimicrobial applications. Screening for antagonistic bacteria was conducted by bacterial isolation from Dead Sea mud samples and agar plate antagonistic assay. The potential antagonistic isolates were subjected to biochemical characterization and identification by 16S-rRNA sequencing. Among the collected isolates, four isolates showed potential antagonistic activity against Bacillus subtilis 6633 and Escherichia coli 8739. The most active isolate (24-DSM) was subjected for antagonistic activity and minimal inhibitory concentration against different gram positive and negative bacterial strains after cultivation in different salt concentration media. Results: The results of 16S-rRNA analysis revealed that 24-DSM is very closely related to Bacillus persicus strain B48, which was isolated from hypersaline lake in Iran. Therefore, the isolate 24-DSM is assigned as a new strain of B. persicusi isolated from the Dead Sea mud. B. persicusi 24-DSM showed higher antimicrobial activity, when it was cultivated with saline medium, against all tested bacterial strains, where the most sensitive bacterial strain was Corynebacterium diphtheria 51696.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arnis Judzis
2003-07-01
This document details the progress to date on the ''OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE--A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING'' contract for the quarter starting April 2003 through June 2003. The DOE and TerraTek continue to wait for Novatek on the optimization portion of the testing program (they are completely rebuilding their fluid hammer). Accomplishments included the following: (1) Hughes Christensen has recently expressed interest in the possibility of a program to examine cutter impact testing, which would be useful in a better understanding of the physics of rock impact. Their interest however is notmore » necessarily fluid hammers, but to use the information for drilling bit development. (2) Novatek (cost sharing supplier of tools) has informed the DOE project manager that their tool may not be ready for ''optimization'' testing late summer 2003 (August-September timeframe) as originally anticipated. During 3Q Novatek plans to meet with TerraTek to discuss progress with their tool for 4Q 2003 testing. (3) A task for an addendum to the hammer project related to cutter impact studies was written during 2Q 2003. (4) Smith International internally is upgrading their hammer for the optimization testing phase. One currently known area of improvement is their development program to significantly increase the hammer blow energy.« less
Late Quaternary stratigraphy and depositional history of the Long Island Sound basin
Lewis, Ralph S.; Stone, Janet R.
1991-01-01
Where quiet waters prevail, marine mud generally less than 15 m thick blankets the older deposits of the Basin. Elsewhere, especially in eastern LIS, tidal currents are actively reworking and transporting glacial and postglacial deposits.
Bushart, T J; Cannon, A; Clark, G; Roux, S J
2014-01-01
Spores of the fern Ceratopteris richardii have proven to be a valuable single-cell system for studying gravity responses. The earliest cellular change directed by gravity in these cells is a trans-cell calcium current, which peaks near 10 h after the spores are induced to germinate. This current is needed for gravity-directed axis alignment, and its peak is coincident with the time period when gravity polarises the direction of subsequent nuclear migration and rhizoid growth. Transcriptomic analysis of genes expressed at the 10-h time point revealed several that encode proteins likely to be key components that either drive the current or regulate it. Notable among these is a plasma membrane (PM)-type Ca(2+) ATPase, CrACA1, whose activity pumping Ca(2+) out of cells is regulated by gravity. This report provides an initial characterisation of the structure and expression of this protein, and demonstrates its heterologous function complementing the K616 mutant of yeast, which is deficient in PM-type Ca(2+) pump activity. Gravity-induced changes in the trans-cell Ca(2+) current occur within seconds, a result consistent with the hypothesis that the force of gravity can rapidly alter the post-translational state of the channels and pumps that drive this current across spore cells. This report identifies a transporter likely to be a key driver of the current, CrACA1, and characterises the role of this protein in early germination and gravity-driven polarity fixation through analysis of expression levels, functional complementation and pharmacological treatments. These data, along with newly available transcriptomic data obtained at the 10-h time point, indicate that CrACA1 is present, functional and likely a major contributing component of the trans-cell Ca(2+) efflux. CrACA1 is not necessary for polar axis alignment, but pharmacological perturbations of it disrupt rhizoid development. These data support and help refine the post-translational modification model for gravity responses. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.
2011-01-01
Background Determination of residual activity of insecticides is essential information for the selection of appropriate indoor spraying operation. The present study was undertaken to evaluate the residual effect of three candidate insecticide formulations on different indoor surfaces in order to guide future interventions, in the context of Cameroon and other African countries. Methods The study was conducted in the Ntougou neighbourhood in Yaoundé (capital city of Cameroon). Bendiocarb WP, lambda-cyhalothrin CS and deltamethrin WG were sprayed on the indoor wall surfaces of local cement, wood and mud houses. Their effects on the knockdown and mortality of the Kisumu susceptible strain of Anopheles gambiae s.s were assessed each month from March to September 2009, using the WHO plastic cones test. Knockdown and mortality rates were compared between different surfaces using Chi-square test. A Kaplan-Meir model was used to estimate the time of treatment failure. Results With bendiocarb WP, the knockdown rates were frequently above 98% during 13 weeks after spraying, except on mud walls where it significantly decreased at the 13th week (P < 0.05). With lambda cyhalothrin CS, the knockdown rates remained 100% on wood surfaces during the 26 weeks trial. However, it significantly decreased on concrete and mud surfaces from the 11th (83%) and the 20th (88%) weeks respectively (P < 0.05). With deltamethrin WG, it remained high on concrete surfaces during 26 weeks (> 98%); while it varied between 60 and 100% on wood or mud surfaces. The survival estimates of bendiocarb WP treatments remaining effective in killing An. gambiae s.s. (mortality rate ≥ 80%) was > 13 weeks on cement and wood surfaces and 13 weeks on mud surfaces. Those of lambda-cyhalothrin CS were > 26 weeks on wood surfaces, and 20 weeks on concrete and mud surfaces. By contrast, those of deltamethrin WG were 26 weeks on concrete, 20 weeks on mud surfaces and 15 weeks on wood surfaces. Conclusion Current data suggest variable durations of spray cycles for each product, according to the type of wall surfaces, highlighting the importance of testing candidate products in local context before using them in large scale. PMID:22047173
The diversity of mud volcanoes in the landscape of Azerbaijan
NASA Astrophysics Data System (ADS)
Rashidov, Tofig
2014-05-01
As the natural phenomenon the mud volcanism (mud volcanoes) of Azerbaijan are known from the ancient times. The historical records describing them are since V century. More detail study of this natural phenomenon had started in the second half of XIX century. The term "mud volcano" (or "mud hill") had been given by academician H.W. Abich (1863), more exactly defining this natural phenomenon. All the previous definitions did not give such clear and capacious explanation of it. In comparison with magmatic volcanoes, globally the mud ones are restricted in distribution; they mainly locate within the Alpine-Himalayan, Pacific and Central Asian mobile belts, in more than 30 countries (Columbia, Trinidad Island, Italy, Romania, Ukraine, Georgia, Azerbaijan, Turkmenistan, Iran, Pakistan, Indonesia, Burma, Malaysia, etc.). Besides it, the zones of mud volcanoes development are corresponded to zones of marine accretionary prisms' development. For example, the South-Caspian depression, Barbados Island, Cascadia (N.America), Costa-Rica, Panama, Japan trench. Onshore it is Indonesia, Japan, and Trinidad, Taiwan. The mud volcanism with non-accretionary conditions includes the areas of Black Sea, Alboran Sea, the Gulf of Mexico (Louisiana coast), Salton Sea. But new investigations reveal more new mud volcanoes and in places which were not considered earlier as the traditional places of mud volcanoes development (e.g. West Nile Rive delta). Azerbaijan is the classic region of mud volcanoes development. From over 800 world mud volcanoes there are about 400 onshore and within the South-Caspian basin, which includes the territory of East Azerbaijan (the regions of Shemakha-Gobustan and Low-Kura River, Absheron peninsula), adjacent water area of South Caspian (Baku and Absheron archipelagoes) and SW Turkmenistan and represents an area of great downwarping with thick (over 25 km) sedimentary series. Generally, in the modern relief the mud volcanoes represent more or less large uplifts on surface, often of plane-conical shape, rising for 5 to 400 m and more over the country (for example, mud volcano Toragay, 400 m height). The base diameter is from 100 m to 3-4 km and more. Like the magmatic ones, the mud volcanoes are crowned with crater of convex-plane or deeply-seated shape. In Azerbaijan there are all types of mud volcanoes: active, extinct, buried, submarine, island, abundantly oil seeping. According to their morphology they are defined into cone-shaped, dome-shaped, ridge-shaped, plateau-shaped. The crater shapes are also various: conical, convex-plane, shield-shaped, deeply-seated, caldera-like. The most complete morphological classification was given in "Atlas of mud volcanoes of Azerbaijan" (Yakubov et al., 1971). Recently (Aliyev Ad. et al., 2003) it was proposed a quite new morphological classification of mud volcanoes of Azerbaijan. For the first time the mud volcanic manifestations had been defined. Volcanoes are ranged according to morphological signs, crater shape and type of activity.
Members of the methanotrophic genus Methylomarinum inhabit inland mud pots
Fradet, Danielle T.; Orphan, Victoria J.
2016-01-01
Proteobacteria capable of converting the greenhouse gas methane to biomass, energy, and carbon dioxide represent a small but important sink in global methane inventories. Currently, 23 genera of methane oxidizing (methanotrophic) proteobacteria have been described, although many are represented by only a single validly described species. Here we describe a new methanotrophic isolate that shares phenotypic characteristics and phylogenetic relatedness with the marine methanotroph Methylomarinum vadi. However, the new isolate derives from a terrestrial saline mud pot at the northern terminus of the Eastern Pacific Rise (EPR). This new cultivar expands our knowledge of the ecology of Methylomarinum, ultimately towards a fuller understanding of the role of this genus in global methane cycling. PMID:27478692
Feasibility of Using Dredged Mud for Prepared the Permeable Brick
NASA Astrophysics Data System (ADS)
Zhou, Chaoqun; Cheng, Xiaosu; Zeng, Lingke; Wang, Hui; Chen, Jing
2017-10-01
Through experimental analysis found that the chemical composition of the dredged mud is similar to clay and the dredged mud does not leach heavy metals. Using the dredged mud in the preparation of permeable bricks reduced the quantity of incineration dredged mud buried in landfills, and the exploitation and consumption of natural sandstone. The dredged mud needs to be checked by the validation criteria when the second use, so we used the TCLP test to identify hazardous materials. Its leaching of heavy metals was in line with industry standard. And the basic formula of permeable brick were prepared, its performance was in line with national standards. The use of dredged mud preparing eco-friendly permeable bricks, not only solves the problem of environmental pollution, but also gets some economic and social profit.
Hu, Xiaolong; Du, Hai; Ren, Cong; Xu, Yan
2016-04-01
Fermentation pit mud, an important reservoir of diverse anaerobic microorganisms, is essential for Chinese strong-aroma liquor production. Pit mud quality, according to its sensory characteristics, can be divided into three grades: degraded, normal, and high quality. However, the relationship between pit mud microbial community and pit mud quality is poorly understood, as are microbial associations within the pit mud ecosystem. Here, microbial communities at these grades were compared using Illumina MiSeq sequencing of the variable region V4 of the 16S rRNA gene. Our results revealed that the pit mud microbial community was correlated with its quality and environmental factors. Species richness, biodiversity, and relative and/or absolute abundances of Clostridia,Clostridium kluyveri, Bacteroidia, and Methanobacteria significantly increased, with corresponding increases in levels of pH, NH4 (+), and available phosphorus, from degraded to high-quality pit muds, while levels of Lactobacillus, dissolved organic carbon, and lactate significantly decreased, with normal samples in between. Furthermore, 271 pairs of significant and robust correlations (cooccurrence and negative) were identified from 76 genera using network analysis. Thirteen hubs of cooccurrence patterns, mainly under the Clostridia,Bacteroidia,Methanobacteria, and Methanomicrobia, may play important roles in pit mud ecosystem stability, which may be destroyed with rapidly increased levels of lactic acid bacteria (Lactobacillus,Pediococcus, and Streptococcus). This study may help clarify the relationships among microbial community, environmental conditions, and pit mud quality, allow the improvement of pit mud quality by using bioaugmentation and controlling environmental factors, and shed more light on the ecological rules guiding community assembly in pit mud. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Paraformaldehyde-Resistant Starch-Fermenting Bacteria in “Starch-Base” Drilling Mud
Myers, G. E.
1962-01-01
Starch-fermenting bacteria were found in each of 12 samples of nonfermenting starch-base drilling mud examined. Of the 12 samples, 3 contained very active starch-fermenting gram-positive spore-bearing bacilli closely resembling Bacillus subtilis. Similar active starch-fermenting bacteria were found in fermenting starch-base drilling mud and in corn starch and slough water used to prepare such mud. The active starch-fermenting microorganisms completely hydrolyzed 1% (w/v) corn starch within 24 hr at 37.5 C. The active starch-fermenting bacteria isolated from fermenting drilling mud were capable of surviving 12 hr of continuous exposure to 0.1% (w/w) paraformaldehyde or 1 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, with no diminution in starch-fermenting ability. The same organisms fermented starch after 3 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, but not after 4 hr of exposure. The phenomenon of rapid disappearance of paraformaldehyde from fermenting drilling mud was observed in the laboratory using a modified sodium sulfite test. Paraformaldehyde, initially present in a concentration of 0.192 lb per barrel of mud, completely disappeared in 9 hr at 22 to 23 C. A significant decrease in paraformaldehyde concentration was detected 0.5 hr after preparation of the mud. It is suggested that the presence of relatively high concentrations of ammonia and chloride in the mud may facilitate the disappearance of paraformaldehyde. The failure of 0.1% (w/w) paraformaldehyde to inhibit the strong starch-fermenting microorganisms isolated from fermenting drilling mud, and the rapid disappearance of paraformaldehyde from the mud, explains the fermentation of starch which occurred in this mud, despite the addition of paraformaldehyde. PMID:13936949
Clostridium botulinum in Scottish fish farms and farmed trout.
Burns, G F; Williams, H
1975-02-01
Rainbow trout and specimens of pond mud were collected from three fish farms and examined for the presence of Clostridium botulinum. Two of the farms were constructed with concrete channels and one was mud-bottomed. Cl. botulinum was isolated only from the mud-bottomed farm (24% of muds), and the isolates were all non-proteolytic type B. The implications of the presence of Cl. botulinum spores in the mud of fish farms is discussed.
NASA Astrophysics Data System (ADS)
Liu, Lei; Chen, Hongde; Zhong, Yijiang; Wang, Jun; Xu, Changgui; Chen, Anqing; Du, Xiaofeng
2017-10-01
Sediment gravity flow deposits are common, particularly in sandy formations, but their origin has been a matter of debate and there is no consensus about the classification of such deposits. However, sediment gravity flow sandstones are economically important and have the potential to meet a growing demand in oil and gas exploration, so there is a drive to better understand them. This study focuses on sediment gravity flow deposits identified from well cores in Palaeogene deposits from the Liaodong Bay Depression in Bohai Bay Basin, China. We classify the sediment gravity flow deposits into eight lithofacies using lithological characteristics, grain size, and sedimentary structures, and interpret the associated depositional processes. Based on the scale, spatial distribution, and contact relationships of sediment gravity flow deposits, we defined six types of lithofacies associations (LAs) that reflect transformation processes and depositional morphology: LA1 (unconfined proximal breccia deposits), LA2 (confined channel deposits), LA3 (braided-channel lobe deposits), LA4 (unconfined lobe deposits), LA5 (distal sheet deposits), and LA6 (non-channelized sheet deposits). Finally, we established three depositional models that reflect the sedimentological characteristics and depositional processes of sediment gravity flow deposits: (1) slope-apron gravel-rich depositional model, which involves cohesive debris flows deposited as LA1 and dilute turbidity currents deposited as LA5; (2) non-channelized surge-like turbidity current depositional model, which mainly comprises sandy slumping, suspended load dominated turbidity currents, and dilute turbidity currents deposited as LA5 and LA6; and (3) channelized subaqueous-fan depositional model, which consists of non-cohesive bedload dominated turbidity currents, suspended load dominated turbidity currents, and dilute turbidity currents deposited as LA2-LA5, originating from sustained extrabasinal turbidity currents (hyperpycnal flow). The depositional models may be applicable to oil and gas exploration and production from sediment gravity flow systems in similar lacustrine depositional environments elsewhere.
Liu, Chia-Chuan; Maity, Jyoti Prakash; Jean, Jiin-Shuh; Sracek, Ondra; Kar, Sandeep; Li, Zhaohui; Bundschuh, Jochen; Chen, Chien-Yen; Lu, Hsueh-Yu
2011-01-01
Fluid and mud samples collected from Hsiaokunshui (HKS), Wushanting (WST), Yenshuikeng (YSK), Kunshuiping (KSP), Liyushan (LYS), and Sinyangnyuhu (SYNH) mud volcanoes of southwestern Taiwan were characterized for major ions, humic substances (HS) and trace elements concentrations. The relationship between the release of arsenic (As) and activities of sulfate-reducing bacteria has been assessed to understand relevant geochemical processes in the mud volcanoes. Arsenic (0.02-0.06 mg/L) and humic substances (4.13 × 10(-4) to 1.64 × 10(-3) mM) in the fluids of mud volcanoes showed a positive correlation (r = 0.99, p < 0.05) except in Liyushan mud volcano. Arsenic and iron in mud sediments formed two separate groups i) high As, but low Fe in HKS, WST, and SYNH; and ii) low As, but high Fe in the YSK, KSP, and LYS mud volcanoes. The Eh(S.H.E.) values of the mud volcano liquids were characterized by mild to strongly reducing conditions. The HKS, SYNH, and WST mud volcanoes (near the Chishan Fault) belongs to strong reducing environment (-33 to -116 mV), whereas the LYS, YSK, and KSP mud volcanoes located near the coastal plain are under mild reducing environment (-11 to 172 mV). At low Eh values mud volcanoes, saturation index (SI) values of poorly crystalline phases such as amorphous ferric hydroxide indicate understaturation, whereas saturation is reached in relatively high Eh(S.H.E.) values mud volcanoes. Arsenic contents in sediments are low, presumably due to its release to fluids (As/Fe ratio in YSK, KSP, and LYS sediment: 4.86 × 10(-4)-6.20 × 10(-4)). At low Eh(S.H.E.) values (mild to strong reducing environment), arsenic may co-precipitate with sulfides as a consequence of sulfate reduction (As/Fe ratios in WST, HKS, and SYNH sediments: 0.42-0.69).
Valorisation of waste ilmenite mud in the manufacture of sulphur polymer cement.
Contreras, Manuel; Gázquez, Manuel Jesús; García-Díaz, Irene; Alguacil, Francisco J; López, Félix A; Bolívar, Juan Pedro
2013-10-15
This paper reports the preparation of sulphur polymer cements (SPCs) incorporating waste ilmenite mud for use in concrete construction works. The ilmenite mud raw material and the mud-containing SPCs (IMC-SPCs) were characterised physico-chemically and radiologically. The optimal IMC-SPC mixture had a sulphur/mud ratio (w/w) of 1.05 (mud dose 20 wt%); this cement showed the greatest compressive strength (64 MPa) and the lowest water absorption coefficient (0.4 g cm(-2) at 28 days). Since ilmenite mud is enriched in natural radionuclides, such as radium isotopes (2.0·10(3) Bq kg(-1)(228)Ra and 5.0·10(2) Bq kg(-1)(226)Ra), the IMC-SPCs were subjected to leaching experiments, which showed their environmental impact to be negligible. The activity concentration indices for the different radionuclides in the IMC-SPCs containing 10% and 20% ilmenite mud met the demands of international standards for materials used in the construction of non-residential buildings. Copyright © 2013 Elsevier Ltd. All rights reserved.
Numerical investigation of split flows by gravity currents into two-layered stratified water bodies
NASA Astrophysics Data System (ADS)
Cortés, A.; Wells, M. G.; Fringer, O. B.; Arthur, R. S.; Rueda, F. J.
2015-07-01
The behavior of a two-dimensional (2-D) gravity current impinging upon a density step in a two-layered stratified basin is analyzed using a high-resolution Reynolds-Averaged Navier-Stokes model. The gravity current splits at the density step, and the portion of the buoyancy flux becoming an interflow is largely controlled by the vertical distribution of velocity and density within the gravity current and the magnitude of the density step between the two ambient layers. This is in agreement with recent laboratory observations. The strongest changes in the ambient density profiles occur as a result of the impingement of supercritical currents with strong density contrasts, for which a large portion of the gravity current detaches from the bottom and becomes an interflow. We characterize the current partition process in the simulated experiments using the densimetric Froude number of the current (Fr) across the density step (upstream and downstream). When underflows are formed, more supercritical currents are observed downstream of the density step compared to upstream (Fru < Frd), and thus, stronger mixing of the current with the ambient water downstream. However, when split flows and interflows are formed, smaller Fr values are identified after the current crosses the density step (Fru > Frd), which indicates lower mixing between the current and ambient water after the impingement due to the significant stripping of interfacial material at the density step.
NASA Astrophysics Data System (ADS)
Depreiter, Davy; van Holland, Gijsbert; Lanckriet, Thijs; Beirinckx, Kirsten; Vanlede, Joris; Maris, Tom
2015-04-01
In this presentation, results from different monitoring and research projects (OMES, MONEOS, Flexible Disposal and Marine-Fluvial mud ratio) will be integrated to increase the insight in the trends and relation between mud disposal and the increasing sediment concentrations (SSC) in the Lower Sea Scheldt. In the Scheldt Estuary, major projects have been carried out in the past decade, among which the third deepening of the navigation channel and the opening of the Deurganck dock. Maintenance dredging is carried out to guarantee a minimum navigation depth. A rising trend in the volume of mud dredged in the Lower Sea Scheldt is observed since 2006, the year after the opening of the Deurganck Dock. The trend is explained by increasing mud volumes dredged in this dock and on a nearby sill. This volume culminated in 2011 (4.8 million m³) when the depth of this dock was increased to its design depth. The dredged mud is disposed upstream, quickly to be resuspended. Near the mud disposal location, yearly averaged SSC (measured at 4.5 m above bed) tripled between 2005 and 2011 (108 to 348 mg/L), and SSC peaks increased even stronger. A multivariate regression model indicated a strong correlation between mud disposal volumes and timing and observed SSC. Mud disposal volumes and SSC where somewhat lower again after 2011. The SSC increase raises an alert with regard to the risk for a regime shift towards a hyperturbid system. Increasing SSC may indeed decrease the hydraulic resistance initiating a feedback mechanism that results in further increasing SSC values. It thus appears that more mud is being circulated: the Deurganck dock acts as mud sink, from which the mud is - after dredging and disposal - resuspended. The mud may have different sources: fluvial or marine influx. The increasing SSC might not only be related to the mud disposal, but also to changing tidal characteristics that enhance the influx of marine suspended sediments. To elucidate this, an analysis of the marine fraction in soil and suspended sediments has also been performed.
Code of Federal Regulations, 2013 CFR
2013-04-01
... damages consisting primarily of eroded shoulders, filled ditches and culverts, pavement settlement, mud..., not related to the increased traffic volumes, such as mowing, maintaining drainage, pavement signing... limited in ER reimbursement to the cost of a new facility to current design standards of comparable...
Code of Federal Regulations, 2010 CFR
2010-04-01
... damages consisting primarily of eroded shoulders, filled ditches and culverts, pavement settlement, mud..., not related to the increased traffic volumes, such as mowing, maintaining drainage, pavement signing... limited in ER reimbursement to the cost of a new facility to current design standards of comparable...
Code of Federal Regulations, 2014 CFR
2014-04-01
... damages consisting primarily of eroded shoulders, filled ditches and culverts, pavement settlement, mud..., not related to the increased traffic volumes, such as mowing, maintaining drainage, pavement signing... limited in ER reimbursement to the cost of a new facility to current design standards of comparable...
Code of Federal Regulations, 2012 CFR
2012-04-01
... damages consisting primarily of eroded shoulders, filled ditches and culverts, pavement settlement, mud..., not related to the increased traffic volumes, such as mowing, maintaining drainage, pavement signing... limited in ER reimbursement to the cost of a new facility to current design standards of comparable...
Code of Federal Regulations, 2011 CFR
2011-04-01
... damages consisting primarily of eroded shoulders, filled ditches and culverts, pavement settlement, mud..., not related to the increased traffic volumes, such as mowing, maintaining drainage, pavement signing... limited in ER reimbursement to the cost of a new facility to current design standards of comparable...
Terrestrial Gravity Fluctuations
NASA Astrophysics Data System (ADS)
Harms, Jan
2015-12-01
Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10-23 Hz-1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.
Terrestrial Gravity Fluctuations.
Harms, Jan
2015-01-01
Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10 -23 Hz -1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.
[Observation on eggs of Oncomelania hupensis hupensis with scanning electron microscope].
Xia, Q B; Yuan, Y B; Liu, B; Tan, P P
2001-01-01
To observe the structure of the mud hull packed Oncomelania eggs and the surface structure of colloid membrane called the third grade membrane of eggs. Scanning electron microscopy was used to observe Oncomelania snail eggs with integral mud hull collected from eastern Dongting Lake. The mud hull of eggs was made of unshapen small humification combined with earth granules with a diameter of 2.6-9.2 microns. The mud hull in 60 um thickness was honeycomb-like in shape with many small holes and small folds on the wall. There were many round or irregularly round hollownesses on the inner layer of mud hull that contacts colloid membrane but no hole through mud hull. There were some protein fiber networks covering on the colloid membrane and apophysis. The structure of the mud hull showed that the exchange of matter was maintained between eggs and outside, and the mud hull is of great importance to regulating temperature and moisture for the growth of eggs by preventing hydrosoluble substances from penetrating into eggs. The protein fiber networks act on gluing mud hull and buffering outside power. The dense glue membrane might be a main barricade to prevent pharmaceutical molecules from penetrating into eggs.
Malard, Florent; Milpied, Noel; Blaise, Didier; Chevallier, Patrice; Michallet, Mauricette; Lioure, Bruno; Clément, Laurence; Hicheri, Yosr; Cordonnier, Catherine; Huynh, Anne; Yakoub-Agha, Ibrahim; Peffault de Latour, Regis; Mohty, Mohamad
2015-06-01
This retrospective report compared the 4-year outcomes of allogeneic stem cell transplantation (allo-SCT) in 651 adult patients with acute myeloid leukemia receiving a reduced-intensity (RIC) or nonmyeloablative conditioning (NMA) regimen according to the type of unrelated donors. These were either umbilical cord blood (UCB, n = 205), a 9/10 mismatched unrelated donor (MisMUD, n = 99), or a 10/10 matched unrelated donor (MUD, n = 347) graft. Neutrophil recovery was slower in UCB (74.5% by day 42) compared with MisMUD (94.8%) and MUD (95.6%) (P < .001). There was no significant difference in nonrelapse mortality between UCB and both MUD (hazard ratio [HR], 1.05; 95% confidence interval [CI], .62 to 1.78; P = .85) and MisMUD (HR, 1.58; 95% CI, .88 to 2.83; P = .13) The relapse/progression was similar between UCB and MisMUD (HR, .62; 95% CI, .37 to 1.03; P = .07), but was significantly lower in MUD compared with UCB (HR, .60; 95% CI, .39 to .92; P = .02). The rate of extensive chronic graft-versus-host disease (GVHD) was similar between UCB and both MUD (HR, 2.15; 95% CI, .93 to 4.97; P = .08) and MisMUD (HR, 1.84; 95% CI, .68 to 4.95; P = .23). The rate of severe grade III and IV acute GVHD was significantly increased in MisMUD compared with UCB (HR, 2.61; 95% CI, 1.30 to 5.23; P = .007). There was no significant difference in overall survival between UCB and both MisMUD (HR, .98; 95% CI, .66 to 1.45; P = .92) and MUD (HR, .74; 95% CI, .52 to 1.03; P = .08). These data suggest that in the setting of RIC/NMA, allo-SCT UCB is a valid alternative graft source, with significantly less chronic GVHD, compared with MisMUD, when there is no MUD available or when urgent transplantation is needed. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.
Bedform development in mixed sand-mud: The contrasting role of cohesive forces in flow and bed
NASA Astrophysics Data System (ADS)
Baas, Jaco H.; Davies, Alan G.; Malarkey, Jonathan
2013-01-01
The majority of subaqueous sediment on Earth consists of mixtures of cohesive clay and cohesionless sand and silt, but the role of cohesion on the development and stability of sedimentary bedforms is poorly understood. The results of new laboratory flume experiments on bedform development in cohesive, mixed sand-mud beds are compared with the results of previous experiments in which cohesive forces in high concentration clay flows dominated bedform development. Even though both series of mixed sand-mud experiments were conducted at similar flow velocities, the textural and structural properties of the bedforms were sufficiently different to permit the designation of key criteria for identifying bedform generation under cohesive flows against bedform generation on cohesive substrates. These criteria are essential for improving bedform size predictions in sediment transport modelling in modern sedimentary environments and for the reconstruction of depositional processes in the geological record. The current ripples developing on the cohesive, mixed sand-mud beds, with bed mud fractions of up to 18%, were significantly smaller than equivalent bedforms in noncohesive sand. Moreover, the bedform height showed a stronger inversely proportional relationship with initial bed mud fraction than the bedform wavelength. This is in contrast with the bedforms developing under the cohesive clay flows, which tend to increase in size with increasing suspended clay concentration until the flow turbulence is fully suppressed. Selective removal of clay from the mixed beds, i.e., clay winnowing, was found to be an important process, with 82-100% clay entrained into suspension after 2 h of bedform development. This winnowing process led to the development of a sand-rich armouring layer. This armouring layer is inferred to have protected the underlying mixed sand-mud from prolonged erosion, and in conjunction with strong cohesive forces in the bed may have caused the smaller size of the bedforms. Winnowing was less efficient for the bedforms developing under the cohesive clay flows, where bedforms consisting of muddy sand were more characteristic. The winnowed sand was also found to heal irregularly scoured topography, thus reestablishing classic quasitriangular bedform shapes. In cohesive flows, the bedforms had more variable shapes, and the healing process was confined to lower transitional plug flows in which strong turbulence is only present close to the sediment bed. Furthermore, the bedforms on the cohesive beds tended to form angle-of-repose cross lamination, whereas low angle cross lamination was more common in bedforms under cohesive flows. In general terms, erosional bedforms prevail when cohesive forces in the bed dominate bedform dynamics, whereas depositional bedforms prevail when cohesive forces in the flow dominate bedform dynamics. Empirical relationships between the proportion of cohesive mud in the mixed sand-mud bed and the development rate and size of the bedforms are defined for future use in field and laboratory studies.
The "Mud-volcanoes route" (Emilia Apennines, northern Italy)
NASA Astrophysics Data System (ADS)
Coratza, Paola; Castaldini, Doriano
2016-04-01
In the present paper the "Mud-volcanoes route" (MVR), an itinerary unfolds across the districts of Viano, Sassuolo, Fiorano Modenese and Maranello, in which part of the Emilia mud volcanoes fields are located, is presented. The Mud-volanoes route represents an emotional journey that connects places and excellences through the geological phenomenon of mud volcanoes, known with the local name "Salse". The Mud Volcanoes are created by the surfacing of salt water and mud mixed with gaseous and liquid hydrocarbons along faults and fractures of the ground. The name "Salsa"- from Latin salsus - results from the"salt" content of these muddy waters, ancient heritage of the sea that about a million years ago was occupying the current Po Plain. The "Salse" may take the shape of a cone or a level-pool according to the density of the mud. The Salse of Nirano, in the district of Fiorano Modenese, is one of the most important in Italy and among the most complex in Europe. Less extensive but equally charming and spectacular, are the "Salse" located in the districts of Maranello (locality Puianello), Sassuolo (locality Montegibbio) and Viano (locality Casola Querciola and Regnano). These fascinating lunar landscapes have always attracted the interest of researchers and tourist.The presence on the MVR territory of ancient settlements, Roman furnaces and mansions, fortification systems and castles, besides historic and rural buildings, proves the lasting bond between this land and its men. In these places, where the culture of good food has become a resource, we can find wine cellars, dairy farms and Balsamic vinegar factories that enable us to appreciate unique worldwide products. This land gave also birth to some personalities who created unique worldwide famous values, such as the myth of the Ferrrari, the ceramic industry and the mechatronics. The MVR is represented in a leaflet containing, short explanation, photos and a map in which are located areas with mud volcanoes, castles, archaeological sites, historic and holy buildings and represent an initiative for the promotion of the environment, art, wellness, tastes, technology and talent of the territory of districts of Viano, Sassuolo, Fiorano Modenese and Maranello. The MVR presented in this article is an example of how geology can be a starting point and provide continuity for a journey offering close encounters with our region's science, art, history, culture. This research aimed to transform geomorphological sites into a culturally accessible and shared heritage and therefore into a resource for social and economic development in their own territory. Indeed geological sites are considered as new elements that can catalyse the potentialities of a territory which are often neglected or pass unnoticed. In this way the proposal become an instrument for territorial upgrading, by means of qualified measures on abandoned or secondary areas, thus promoting them to the rank of development models.
Adler, A I; Altman, J
1993-01-27
To investigate an outbreak of gram-negative folliculitis in relation to a common exposure, mud wrestling, and identify risk factors for dermatitis among those who mud wrestled. Case-control study. University of Washington, Seattle. Two college-residence groups of students. Cultures from affected students and from mud similar to that used for wrestling yielded Enterobacteriaceae. The odds ratio associated with mud wrestling was 79.5 (95% confidence interval, 13.9 to 895.4). Increased time spent wrestling was associated with increased risk. Skin trauma during wrestling or immersion in the mud increased the risk of infection (odds ratio, 23.1; 95% confidence interval, 1.7 to 1440.4). Mud wrestling is one cause of pustular follicular dermatitis. Trauma to the skin may be a necessary cofactor for the development of infection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Mud flats. 230.42 Section 230.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING SECTION 404(b)(1... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Mud flats. 230.42 Section 230.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING SECTION 404(b)(1... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Mud flats. 230.42 Section 230.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING SECTION 404(b)(1... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Mud flats. 230.42 Section 230.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING SECTION 404(b)(1... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Mud flats. 230.42 Section 230.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING SECTION 404(b)(1... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal...
30 CFR 250.1614 - Mud program.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Mud program. 250.1614 Section 250.1614 Mineral... OPERATIONS IN THE OUTER CONTINENTAL SHELF Sulphur Operations § 250.1614 Mud program. (a) The quantities, characteristics, use, and testing of drilling mud and the related drilling procedures shall be designed and...
MUD for Learning: Classification and Instruction
ERIC Educational Resources Information Center
Hsieh, Chung-Hsiang; Sun, Chuen-Tsai
2006-01-01
From a constructivist point of view, the importance of MUDs (Multiple User Dungeons) in education is justified based on their community-forming, learning, and role-playing functions. The authors propose a typology for educational MUDs and discuss their individual instructional approaches in order to measure MUD potential in ten-os of…
Rumisha, Cyrus; Huyghe, Filip; Rapanoel, Diary; Mascaux, Nemo; Kochzius, Marc
2017-01-01
The giant mud crab Scylla serrata provides an important source of income and food to coastal communities in East Africa. However, increasing demand and exploitation due to the growing coastal population, export trade, and tourism industry are threatening the sustainability of the wild stock of this species. Because effective management requires a clear understanding of the connectivity among populations, this study was conducted to assess the genetic diversity and connectivity in the East African mangrove crab S. serrata. A section of 535 base pairs of the cytochrome oxidase subunit I (COI) gene and eight microsatellite loci were analysed from 230 tissue samples of giant mud crabs collected from Kenya, Tanzania, Mozambique, Madagascar, and South Africa. Microsatellite genetic diversity (He) ranged between 0.56 and 0.6. The COI sequences showed 57 different haplotypes associated with low nucleotide diversity (current nucleotide diversity = 0.29%). In addition, the current nucleotide diversity was lower than the historical nucleotide diversity, indicating overexploitation or historical bottlenecks in the recent history of the studied population. Considering that the coastal population is growing rapidly, East African countries should promote sustainable fishing practices and sustainable use of mangrove resources to protect mud crabs and other marine fauna from the increasing pressure of exploitation. While microsatellite loci did not show significant genetic differentiation (p > 0.05), COI sequences revealed significant genetic divergence between sites on the East coast of Madagascar (ECM) and sites on the West coast of Madagascar, mainland East Africa, as well as the Seychelles. Since East African countries agreed to achieve the Convention on Biological Diversity (CBD) target to protect over 10% of their marine areas by 2020, the observed pattern of connectivity and the measured genetic diversity can serve to provide useful information for designing networks of marine protected areas.
NASA Technical Reports Server (NTRS)
Van Dresar, N. T.
1992-01-01
A review of technology, history, and current status for pressurized expulsion of cryogenic tankage is presented. Use of tank pressurization to expel cryogenic fluid will continue to be studied for future spacecraft applications over a range of operating conditions in the low-gravity environment. The review examines experimental test results and analytical model development for quiescent and agitated conditions in normal-gravity followed by a discussion of pressurization and expulsion in low-gravity. Validated, 1-D, finite difference codes exist for the prediction of pressurant mass requirements within the range of quiescent normal-gravity test data. To date, the effects of liquid sloshing have been characterized by tests in normal-gravity, but analytical models capable of predicting pressurant gas requirements remain unavailable. Efforts to develop multidimensional modeling capabilities in both normal and low-gravity have recently occurred. Low-gravity cryogenic fluid transfer experiments are needed to obtain low-gravity pressurized expulsion data. This data is required to guide analytical model development and to verify code performance.
NASA Technical Reports Server (NTRS)
Vandresar, N. T.
1992-01-01
A review of technology, history, and current status for pressurized expulsion of cryogenic tankage is presented. Use of tank pressurization to expel cryogenic fluids will continue to be studied for future spacecraft applications over a range of operating conditions in the low-gravity environment. The review examines experimental test results and analytical model development for quiescent and agitated conditions in normal-gravity, followed by a discussion of pressurization and expulsion in low-gravity. Validated, 1-D, finite difference codes exist for the prediction of pressurant mass requirements within the range of quiescent normal-gravity test data. To date, the effects of liquid sloshing have been characterized by tests in normal-gravity, but analytical models capable of predicting pressurant gas requirements remain unavailable. Efforts to develop multidimensional modeling capabilities in both normal and low-gravity have recently occurred. Low-gravity cryogenic fluid transfer experiments are needed to obtain low-gravity pressurized expulsion data. This data is required to guide analytical model development and to verify code performance.
Origin of lipid biomarkers in mud volcanoes from the Alboran Sea, western Mediterranean
NASA Astrophysics Data System (ADS)
López-Rodríguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruíz, F.; Comas, M.
2014-06-01
Mud volcanoes (MVs) are the most prominent indicators of active methane/hydrocarbon venting at the seafloor on both passive and active continental margins. Their occurrence in the western Mediterranean is patent at the West Alboran Basin, where numerous MVs develop overlaying a major sedimentary depocentre containing overpressured shales. Although some of these MVs have been studied, the detailed biogeochemistry of expelled mud so far has not been examined in detail. This work provides the first results on the composition and origin of organic matter, anaerobic oxidation of methane (AOM) processes and general characteristics on MV dynamics using lipid biomarkers as the main tool. Lipid biomarker analysis was performed on MV expelled material (mud breccias) and interbedded hemipelagic sediments from Perejil, Kalinin and Schneider's Heart MVs located in the northwest margin of the Alboran Sea. The n alkane distributions and n alkane-derived indices (CPI and ACL), in combination with the epimerization degree of hopanes (22S/(22S+22R)) indicate that all studied mud breccia have a similar biomarker composition consisting of mainly thermally immature organic matter with an admixture of petroleum-derived compounds. This concordant composition indicates that common source strata must feed all three studied MVs. The past or present AOM activity was established using lipid biomarkers specific for anaerobic methanotrophic archaea (irregular isoprenoids and dialkyl glycerol diethers) and the depleted carbon isotope composition (δ13C) of crocetane/phytane. The presence of these lipid biomarkers, together with the low amounts of detected glycerol dialkyl glycerol tetraethers, is consistent with the dominance of anaerobic methanotrophs of the ANME-2 over ANME-1, at least in mud breccia from Perejil MVs. In contrast, the scarce presence or lack of these AOM-related lipid biomarkers in sediments from Kalinin and Schneider's Heart MVs, suggests that no recent active methane seepage has occurred at these sites. Moreover, the observed methane concentrations support the current activity of Perejil MV, and the very low methane seepage activity in Kalinin and Schneider's Heart MVs.
NASA Astrophysics Data System (ADS)
Krueger, Martin; Straaten, Nontje; Mazzini, Adriano
2015-04-01
The Lusi eruption represents one of the largest ongoing sedimentary hosted geothermal systems. This eruption started in 2006 following to a 6.3 M earthquake that stroke Java Island. Since then it has been spewing boiling mud from a central crater with peaks reaching 180.000 m3 per day. Today an area of about 8 km2 is covered by locally dried mud breccia where a network of hundreds of satellite seeping pools is active. Numerous investigations focused on the study of offshore microbial colonies that commonly thrive at offshore methane seeps and mud volcanoes, however very little has been done for onshore seeping structures. Lusi represents a unique opportunity to complete a comprehensive study of onshore microbial communities fed by the seepage of CH4 and CO2 as well as of heavier liquid hydrocarbons originating from several km below the surface. We conducted a sampling campaign at the Lusi site collecting samples of fresh mud close to the erupting crater using a remote controlled drone. In addition we completed a transect towards outer parts of the crater to collect older, weathered samples for comparison. In all samples active microorganisms were present. The highest activities for CO2 and CH4 production as well as for CH4 oxidation and hydrocarbon degradation were observed in medium-age mud samples collected roughly in the middle of the transect. Rates for aerobic methane oxidation were high, as was the potential of the microbial communities to degrade hydrocarbons (oils, alkanes, BTEX tested). The data suggests a transition of microbial populations from an anaerobic, hydrocarbon-driven metabolism in fresher samples from center or from small seeps to more generalistic, aerobic microbial communities in older, more consolidated sediments. Currently, the microbial communities in the different sediment samples are analyzed using quantitative PCR and T-RFLP combined with MiSeq sequencing. This study represents an initial step to better understand onshore seepage systems and provides an ideal analogue for comparison with the better investigated offshore structures.
Late Glacial and Holocene gravity deposits in the Gulf of Lions deep basin, Western Mediterranean
NASA Astrophysics Data System (ADS)
Dennielou, B.; Bonnel, C.; Sultan, N.; Voisset, M.; Berné, S.; Beaudouin, C.; Guichard, F.; Melki, T.; Méar, Y.; Droz, L.
2003-04-01
Recent investigations in the Gulf of Lions have shown that complex gravity processes and deposits occurred in the deep basin since the last Glacial period. Besides the largest western Mediterranean turbiditic system, Petit-Rhône deep-sea fan (PRDSF), whose built-up started at the end of Pliocene, several sedimentary bodies can be distinguished: (1) The turbiditic Pyreneo-Languedocian ridge (PLR), at the outlet of the Sète canyon network, whose activity is strongly connected to the sea level and the connection of the canyons with the rivers. It surface shows long wave-length sediment waves, probably in relation with the turbiditic overspill. (2) An acoustically chaotic unit, filling the topographic low between the PRDSF and the PLR, the Lower Interlobe Unit. Possible source areas are the Sète canyon and/or the Marti Canyon. (3) An acoustically transparent unit, below the neofan, filling the same topographic low, the Western Transparent Unit, interpreted as a debris-flow. Recent sediment cores have shown that this sedimentary is composed of folded, laminated mud, both in its northern and southern fringes. (4) The Petit-Rhône neofan, a channelized turbiditic lobe resulting from the last avulsion of the Petit-Rhône turbiditic channel and composed of two units. The lower, acoustically chaotic facies unit, corresponding to an initial stage of the avulsion, similar to the HARP facies found on the Amazon fan. The upper, transparent, slightly bedded, channel-levee shaped unit, corresponding to the channelized stage of the avulsion. (5) Up to ten, Deglacial to Holocene, thin, fine sand layers, probably originating from shelf-break sand accumulations, through the Sète canyon network. (6) Giant scours, in the southern, distal part of the neofan, possibly linked to turbiditic overflow from the neo-channel, probably corresponding to channel-lobe transition zone features (Wynn et al. 2002). Recent investigations have shown no evidence of bottom current features.
Toxicity of used drilling fluids to mysids (Mysidopsis bahia)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gaetz, C.T.; Montgomery, R.; Duke, T.W.
1986-01-01
Static, acute toxicity tests were conducted with mysids (Mysidopsis bahia) and 11 used drilling fluids (also called drilling muds) obtained from active drilling platforms in the Gulf of Mexico, U.S.A. Each whole mud was tested, along with three phases of each mud: a liquid phase with all particulate materials removed; a suspended particulate phase composed of soluble and lighter particulate fractions; and a solid phase composed mainly of drill cuttings and rapidly settling particulates. These muds represented seven of the eight generic mud types described by the U.S. Environmental Protection Agency for use on the U.S. Outer Continental Shelf. Themore » toxicity of the 11 muds tested was apparently enhanced by the presence of aromatics. Furthermore, one mud tested repeatedly showed loss of toxicity with time, possibly from volatilization of aromatic fractions. The data demonstrated that aromatics in the drilling fluids affected their toxicity to M. bahia.« less
[Sulphureous mud-bath therapy and changes in blood pressure: observational investigation].
Costantino, M; Marongiu, M B; Russomanno, G; Conti, V; Manzo, V; Filippelli, A
2015-01-01
The chronic arthropathies currently appear to be a major cause of disability with a negative impact on quality of life and health care spending. The mud-bath therapy is a spa treatment that induces benefic effects in chronic rheumatic diseases. It has long been debated on the assumption that the mud-bath spa therapy could have adverse cardiovascular effects which often induce caution and even a contraindication to the use of this treatment in chronic arthropathies associated with cardiovascular alterations such as hypertension. The aim of this observational study was to investigate, in arthrorheumatic subjects, the effects of sulphureous mud-bath cycle on blood pressure and the possible appearance of adverse drug reaction. 169 patients, with age range 42-86 years, suffering by chronic arthropathies were treated with sulphureous mud-bath therapy for 2 weeks. According to the arterial pressure values, measured before the spa treatment, the patients considered were divided in three groups: with normal blood pressure (NOR group); with high blood pressure, after, the latter group was divided in IPET (patients in treatment with antihypertensive drugs) and IPENT (patients not in antihypertensive therapy). The arterial pressure values, maximum and minimum, expressed in mmHg, were detected in the first (T1) - sixth (T6) and twelfth (T12) day of spa treatment. The media arterial pressure values collected before and after T1, before and after T6, before and after T12 , before T1 and after T12 were compared. The data, presented as mean±SD, were compared with the paired Student t test. A p value ≤0.05 was considered significant. The comparison between the mean values detected in pre and post T1, pre and post T6, pre and post T12 have showed that sulphureous mud-bath therapy induced a significant (p<0.05) reduction of arterial blood pressure values in patients suffering of chronic arthropathies with high blood pressure in antihypertensive therapy or not (IPET and IPENT groups); while in patients with normal blood pressure (NOR group) were observed modest reduction at the limit of statistical significance. Similarly, the comparison between the data detected at the end of sulphureous mud-bath therapy (post-T12) vs baseline (pre-T1) have demonstrated: in IPET and IPENT groups a significant (p<0,01) decrease of arterial blood pressure values; in NOR group very small decrease, this reduction is significant (p<0.05) only for maximum arterial pressure value. Were not observed adverse drug reaction. The results of our study, in according with the few data in the literature, evidenced that is possible include the sulphureous mud-bath therapy in interdisciplinary therapeutic p rotocol of patients suffering of chronic arthropathies and arterial hypertension.
A summary of existing and planned experiment hardware for low-gravity fluids research
NASA Technical Reports Server (NTRS)
Hill, Myron E.; Omalley, Terence F.
1991-01-01
An overview is presented of (1) existing ground-based, low gravity research facilities, with examples of hardware capabilities, and (2) existing and planned space-based research facilities, with examples of current and past flight hardware. Low-gravity, ground-based facilities, such as drop towers and aircraft, provide the experimenter with quick turnaround time, easy access to equipment, gravity levels ranging from 10(exp -2) to 10(exp -6) G, and low-gravity durations ranging from 2 to 30 sec. Currently, the only operational space-based facility is the Space Shuttle. The Shuttle's payload bay and middeck facilities are described. Existing and planned low-gravity fluids research facilities are also described with examples of experiments and hardware capabilities.
Safety evaluation of traces of nickel and chrome in cosmetics: The case of Dead Sea mud.
Ma'or, Ze'evi; Halicz, Ludwik; Portugal-Cohen, Meital; Russo, Matteo Zanotti; Robino, Federica; Vanhaecke, Tamara; Rogiers, Vera
2015-12-01
Metal impurities such as nickel and chrome are present in natural ingredients-containing cosmetic products. These traces are unavoidable due to the ubiquitous nature of these elements. Dead Sea mud is a popular natural ingredient of cosmetic products in which nickel and chrome residues are likely to occur. To analyze the potential systemic and local toxicity of Dead Sea mud taking into consideration Dead Sea muds' natural content of nickel and chrome. The following endpoints were evaluated: (Regulation No. 1223/20, 21/12/2009) systemic and (SCCS's Notes of Guidance) local toxicity of topical application of Dead Sea mud; health reports during the last five years of commercial marketing of Dead Sea mud. Following exposure to Dead Sea mud, MoS (margin of safety) calculations for nickel and chrome indicate no toxicological concern for systemic toxicity. Skin sensitization is also not to be expected by exposure of normal healthy skin to Dead Sea mud. Topical application, however, is not recommended for already nickel-or chrome-sensitized persons. As risk assessment of impurities present in cosmetics may be a difficult exercise, the case of Dead Sea mud is taken here as an example of a natural material that may contain traces of unavoidable metals. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Volume requirements for aerated mud drilling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, B.; Rajtar, J.M.
1995-09-01
Aerated mud drilling has been recognized as having many advantages over conventional mud drilling, such ass higher penetration rate, less formation damage, minimized lost circulation, and lower drilling cost. In some areas, the use of aerated mud as a circulating medium for drilling oil and gas wells is becoming an attractive practice. Maintaining an optimum combination of liquid and air flow rates is important in aerated drilling operations. However, most drilling operators are unclear on what constitutes the ``optimum combination of the liquid and air flow rates.`` Guo et al. presented a mathematical approach to determining the flowing bottomhole pressuremore » (BHP) for aerated mud drilling. This paper addresses the use of Guo et al.`s mathematical model to determine liquid and air volume requirements considering wellbore stability, pipe sticking, and formation damage as well as the cuttings-carry capacity of the aerated mud. For a formation-damage-prevention point of view, the liquid fraction in the fluid stream should e as low as possible. However, a sufficient mud flow rate is always required to make the hole stable and to maintain the cuttings-carrying capacity of the aerated mud without injecting much air volume. This paper provides a simple approach to determining the liquid and air volume requirements for aerated mud drilling.« less
Loher, M; Pape, T; Marcon, Y; Römer, M; Wintersteller, P; Praeg, D; Torres, M; Sahling, H; Bohrmann, G
2018-04-19
Submarine mud volcanoes release sediments and gas-rich fluids at the seafloor via deeply-rooted plumbing systems that remain poorly understood. Here the functioning of Venere mud volcano, on the Calabrian accretionary prism in ~1,600 m water depth is investigated, based on multi-parameter hydroacoustic and visual seafloor data obtained using ship-borne methods, ROVs, and AUVs. Two seepage domains are recognized: mud breccia extrusion from a summit, and hydrocarbon venting from peripheral sites, hosting chemosynthetic ecosystems and authigenic carbonates indicative of long-term seepage. Pore fluids in freshly extruded mud breccia (up to 13 °C warmer than background sediments) contained methane concentrations exceeding saturation by 2.7 times and chloride concentrations up to five times lower than ambient seawater. Gas analyses indicate an underlying thermogenic hydrocarbon source with potential admixture of microbial methane during migration along ring faults to the peripheral sites. The gas and pore water analyses point to fluids sourced deep (>3 km) below Venere mud volcano. An upward-branching plumbing system is proposed to account for co-existing mud breccia extrusion and gas seepage via multiple surface vents that influence the distribution of seafloor ecosystems. This model of mud volcanism implies that methane-rich fluids may be released during prolonged phases of moderate activity.
Experiment study of mud to the moving process influent about viscous debris flow along slope
NASA Astrophysics Data System (ADS)
Jun, JiXian; Ying, Liang; Li, Pan Hua; Qiang, OuGuo
2018-01-01
Mud is the main component of viscous debris flow. The physical model experiments of viscous debris flow were carried out through the mixing mud with different density and fixed components of coarse particles. The width, longitudinal movement distance and motion velocity were recorded by video cameras during experiment. Through viscous debris flow physical model experiments, the influence of mud to transverse width, longitudinal movement distance and motion velocity was discussed. The physical model experiment results show that the motion forms change from inviscid particle flow to viscous debris flow and to the whole mass sliding with the increase of mud density; the width and the length along the slope decrease with mud density increasing; the movement process has classified phenomena about viscous debris flow composed by different mud densities: the velocity increases rapidly with time and the change gradient is steady when the density of mud is lower than 1.413g/cm3; the movement process can be divided into two stages when the density of mud is higher than 1.413g/cm3: the movement velocity is lower and the gradient change is small in the initial stage; but in the second stage, the movement velocity increases quickly, and the gradient is higher than the first stage, and with steady value.
Acoustic scattering from mud volcanoes and carbonate mounds.
Holland, Charles W; Weber, Thomas C; Etiope, Giuseppe
2006-12-01
Submarine mud volcanoes occur in many parts of the world's oceans and form an aperture for gas and fluidized mud emission from within the earth's crust. Their characteristics are of considerable interest to the geology, geophysics, geochemistry, and underwater acoustics communities. For the latter, mud volcanoes are of interest in part because they pose a potential source of clutter for active sonar. Close-range (single-interaction) scattering measurements from a mud volcano in the Straits of Sicily show scattering 10-15 dB above the background. Three hypotheses were examined concerning the scattering mechanism: (1) gas entrained in sediment at/near mud volcano, (2) gas bubbles and/or particulates (emitted) in the water column, (3) the carbonate bio-construction covering the mud volcano edifice. The experimental evidence, including visual, acoustic, and nonacoustic sensors, rules out the second hypothesis (at least during the observation time) and suggests that, for this particular mud volcano the dominant mechanism is associated with carbonate chimneys on the mud volcano. In terms of scattering levels, target strengths of 4-14 dB were observed from 800 to 3600 Hz for a monostatic geometry with grazing angles of 3-5 degrees. Similar target strengths were measured for vertically bistatic paths with incident and scattered grazing angles of 3-5 degrees and 33-50 degrees, respectively.
Li, Yuan-Cheng; Min, Xiao-Bo; Ke, Yong; Chai, Li-Yuan; Shi, Mei-Qing; Tang, Chong-Jian; Wang, Qing-Wei; Liang, Yan-Jie; Lei, Jie; Liu, De-Gang
2018-02-15
A new method in which Pb/Zn smelter waste containing arsenic and heavy metals (arsenic sludge), red mud and lime are utilized to prepare red mud-based cementitious material (RCM) is proposed in this study. XRD, SEM, FTIR and unconfined compressive strength (UCS) tests were employed to assess the physicochemical properties of RCM. In addition, ettringite and iron oxide-containing ettringite were used to study the hydration mechanism of RCM. The results show that the UCS of the RCM (red mud+arsenic sludge+lime) was higher than that of the binder (red mud+arsenic sludge). When the mass ratio of m (binder): m (lime) was 94:6 and then maintained 28days at ambient temperature, the UCS reached 12.05MPa. The red mud has potential cementitious characteristics, and the major source of those characteristics was the aluminium oxide. In the red mud-arsenic sludge-lime system, aluminium oxide was effectively activated by lime and gypsum to form complex hydration products. Some of the aluminium in ettringite was replaced by iron to form calcium sulfoferrite hydrate. The BCR and leaching toxicity results show that the leaching concentration was strongly dependent on the chemical speciation of arsenic and the hydration products. Therefore, the investigated red mud and arsenic sludge can be successfully utilized in cement composites to create a red mud-based cementitious material. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Rankin, Arturo L.; Matthies, Larry H.
2010-01-01
Robust mud detection is a critical perception requirement for Unmanned Ground Vehicle (UGV) autonomous offroad navigation. A military UGV stuck in a mud body during a mission may have to be sacrificed or rescued, both of which are unattractive options. There are several characteristics of mud that may be detectable with appropriate UGV-mounted sensors. For example, mud only occurs on the ground surface, is cooler than surrounding dry soil during the daytime under nominal weather conditions, is generally darker than surrounding dry soil in visible imagery, and is highly polarized. However, none of these cues are definitive on their own. Dry soil also occurs on the ground surface, shadows, snow, ice, and water can also be cooler than surrounding dry soil, shadows are also darker than surrounding dry soil in visible imagery, and cars, water, and some vegetation are also highly polarized. Shadows, snow, ice, water, cars, and vegetation can all be disambiguated from mud by using a suite of sensors that span multiple bands in the electromagnetic spectrum. Because there are military operations when it is imperative for UGV's to operate without emitting strong, detectable electromagnetic signals, passive sensors are desirable. JPL has developed a daytime mud detection capability using multiple passive imaging sensors. Cues for mud from multiple passive imaging sensors are fused into a single mud detection image using a rule base, and the resultant mud detection is localized in a terrain map using range data generated from a stereo pair of color cameras.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, M.A.; Dodd, J.R.
1990-06-01
Relatively small, lens-shaped carbonate mud bodies are common features in the Ramp Creek Formation and Harrodsburg Limestone (Mississippian) of southern Indiana and northern Kentucky. The outcrop dimensions of the lenses range from approximately 10 cm thick and 3 m wide to as much as 2 m thick and in excess of 100 m wide; their three-dimensional geometry is unknown. The lens cores consist of dolomitic mudstone that grades laterally and vertically into increasingly more fossiliferous wackestone to grainstone with fenestrate bryozoans and echinoderms being the dominant fossils. The great abundance of fenestrate bryozoan fragments surrounding the lenses suggests that lensmore » evolution was controlled by the trapping of carbonate mud by the baffling action of bryozoans. Wisps of organic material preserved in the lens cores may be remnants of some form of non-calcareous algae that also baffled and trapped carbonate mud. These mud lenses are end members of a spectrum of Mississippian carbonate mud bodies ranging in size from these small lenses to the classical Waulsortian mounds that may be hundreds of meters thick and a kilometer or more broad. All of these carbonate mud bodies may have in part formed by baffling and localizing of carbonate mud by organisms and in part by local production of carbonate mud. The major difference between large and small bodies is the water depth in which each formed. The Ramp Creek-Harrodsburg mud lenses may be miniature Waulsortian mounds that developed at or above fair-weather wave base on a relatively shallow carbonate platform rather than on shelf-to-basin slopes as proposed for the classical Waulsortian mounds.« less
Episodic Deep Fluid Expulsion at Mud Volcanoes in the Kumano Forearc Basin, SE Offshore Japan
NASA Astrophysics Data System (ADS)
Hammerschmidt, S.; Kopf, A.
2014-12-01
Compressional forces at convergent margins govern a variety of processes, most prominently earthquakes, landslides and mud volcanoes in the forearc. Although all seem related to fluid pressure changes, mud volcanoes are not only characterized by expulsion of fluids, but also fluidized mud and clasts that got ripped-up during mud ascension. They hence provide information regarding mobilization depth, diagenetic overprint, and geodynamic pathways. At the Nankai Trough subduction zone, SE offshore Japan, mud volcanism id common and supposed to be related to seismogenic processes. During MARUM Expedition SO-222 with R/V SONNE, mud volcanoes in the Kumano forearc basin were mapped, cored and sampled. By extending the Integrated Ocean Drilling Program (IODP) Kumano transect landwards, 5 new mud volcanoes were identified by multibeam mapping. Cores revealed mud breccia with semi-consolidated silt- to claystone clasts and gaseous fluid escape structures, while the hemipelagic background sediments are characterized by intercalations of turbidites, ash layers and calcareous fossils. Clasts were subject to thin-section analyses, and the cores were sampled for XRD analyses and radiocarbon dating. Clasts showed prominent deformation structures, neomorphism and pores and fractures filled with polycrystalline quartz and/or calcite cement, probably formed during deep burial and early metamorphosis. Illite crystallinity based on XRD measurements varies between 0.24 and 0.38, which implies that the material originates from the Anchizone at depths ≥ 4 km. Radiocarbon dating revealed ages between 4450 and 30300 yr cal. BP, with age reversals occurring not earlier than 17000 yr cal. BP. Radiocarbon dating beneath turbidites and ash layers found at mud volcano #9 points to an episodic occurrence of these earthquake-related features in intervals of ca. 620 yr, while the mud volcano itself remained inactive. In summary, the preliminary results suggest that the mud volcanoes are nurtured from a reservoir within the older part of the accretionary prism, but that mud volcanic activity is less frequent than major earthquakes. Future models will focus on source depth and temperature, and might elucidate the prerequisites for fluid migration and its role in seismogenesis at the Nankai Trough subduction zone.
NASA Astrophysics Data System (ADS)
Seifert, Annedore; Stegmann, Sylvia; Mörz, Tobias; Lange, Matthias; Wever, Thomas; Kopf, Achim
2008-08-01
We present in situ strength and pore-pressure measurements from 57 dynamic cone penetration tests in sediments of Mecklenburg ( n = 51), Eckernförde ( n = 2) and Gelting ( n = 4) bays, western Baltic Sea, characterised by thick mud layers and partially free microbial gas resulting from the degradation of organic material. In Mecklenburg and Eckernförde bays, sediment sampling by nine gravity cores served sedimentological characterisation, analyses of geotechnical properties, and laboratory shear tests. At selected localities, high-resolution echo-sounder profiles were acquired. Our aim was to deploy a dynamic cone penetrometer (CPT) to infer sediment shear strength and cohesion of the sea bottom as a function of fluid saturation. The results show very variable changes in pore pressure and sediment strength during the CPT deployments. The majority of the CPT measurements ( n = 54) show initially negative pore-pressure values during penetration, and a delayed response towards positive pressures thereafter. This so-called type B pore-pressure signal was recorded in all three bays, and is typically found in soft muds with high water contents and undrained shear strengths of 1.6-6.4 kPa. The type B signal is further affected by displacement of sediment and fluid upon penetration of the lance, skin effects during dynamic profiling, enhanced consolidation and strength of individual horizons, the presence of free gas, and a dilatory response of the sediment. In Mecklenburg Bay, the remaining small number of CPT measurements ( n = 3) show a well-defined peak in both pore pressure and cone resistance during penetration, i.e. an initial marked increase which is followed by exponential pore-pressure decay during dissipation. This so-called type A pore-pressure signal is associated with normally consolidated mud, with indurated clay layers showing significantly higher undrained shear strength (up to 19 kPa). In Eckernförde and Gelting bays pore-pressure response type B is exclusively found, while in Mecklenburg Bay types A and B were detected. Despite the striking similarities in incremental density increase and shear strength behaviour with depth, gas occurrence and subtle variations in the coarse-grained fraction cause distinct pore-pressure curves. Gaseous muds interbedded with silty and sandy layers are most common in the three bays, and the potential effect of free gas (i.e. undersaturated pore space) on in situ strength has to be explored further.
Lehoux, Alizée P; Lockwood, Cindy L; Mayes, William M; Stewart, Douglas I; Mortimer, Robert J G; Gruiz, Katalin; Burke, Ian T
2013-10-01
Red mud is highly alkaline (pH 13), saline and can contain elevated concentrations of several potentially toxic elements (e.g. Al, As, Mo and V). Release of up to 1 million m(3) of bauxite residue (red mud) suspension from the Ajka repository, western Hungary, caused large-scale contamination of downstream rivers and floodplains. There is now concern about the potential leaching of toxic metal(loid)s from the red mud as some have enhanced solubility at high pH. This study investigated the impact of red mud addition to three different Hungarian soils with respect to trace element solubility and soil geochemistry. The effectiveness of gypsum amendment for the rehabilitation of red mud-contaminated soils was also examined. Red mud addition to soils caused a pH increase, proportional to red mud addition, of up to 4 pH units (e.g. pH 7 → 11). Increasing red mud addition also led to significant increases in salinity, dissolved organic carbon and aqueous trace element concentrations. However, the response was highly soil specific and one of the soils tested buffered pH to around pH 8.5 even with the highest red mud loading tested (33 % w/w); experiments using this soil also had much lower aqueous Al, As and V concentrations. Gypsum addition to soil/red mud mixtures, even at relatively low concentrations (1 % w/w), was sufficient to buffer experimental pH to 7.5-8.5. This effect was attributed to the reaction of Ca(2+) supplied by the gypsum with OH(-) and carbonate from the red mud to precipitate calcite. The lowered pH enhanced trace element sorption and largely inhibited the release of Al, As and V. Mo concentrations, however, were largely unaffected by gypsum induced pH buffering due to the greater solubility of Mo (as molybdate) at circumneutral pH. Gypsum addition also leads to significantly higher porewater salinities, and column experiments demonstrated that this increase in total dissolved solids persisted even after 25 pore volume replacements. Gypsum addition could therefore provide a cheaper alternative to recovery (dig and dump) for the treatment of red mud-affected soils. The observed inhibition of trace metal release within red mud-affected soils was relatively insensitive to either the percentage of red mud or gypsum present, making the treatment easy to apply. However, there is risk that over-application of gypsum could lead to detrimental long-term increases in soil salinity.
On the Hydrogranular Dynamics of Magmatic Gravity Currents
NASA Astrophysics Data System (ADS)
McIntire, M. Z.; Bergantz, G. W.; Schleicher, J.; Burgisser, A.
2016-12-01
Magmatic processes are generally governed by multi-phase interactions of silicate liquid, crystals, and bubbles. However, the modes of dissipation and the manner that stress is transmitted are poorly understood. We use a model of a simple but widely applicable gravity current as a means to exemplify the hydrogranular dynamics in crystal-rich magmas. Viscous and lubrication forces are of special interest because they have a dual role in dispersal and mixing in a crystal-rich gravity current. For example, lubrication forces provide an initial apparent yield strength by inducing a negative pore pressure as crystals move apart. However, once the gravity current is underway, lubrication forces reduce the dissipation due to collision and frictional contact.The gravity current is initiated by a combination of toppling and sliding along a well-defined granular fault. This produces three distinct regimes: a quasi-static base, an overlying particle hump that translates in a quasi-plastic fashion by grain-passing and rolling until the angle of repose is reached, and a viscous particle current. The current initially forms a leading vortex at the head, but the loss of crystals by sedimentation-assisted granular capture by an upward growing particle front drains energy from the flow. The vortex is soon abandoned, but persists in the reservoir as a fossil feature of orphaned crystals in a smear of previous intercumulate fluid. The kinetic energy of the most active crystals decays in a dual fashion, initially linearly, then parabolically with a near symmetrical increase and loss of kinetic energy.There is very little entrainment and mixing between intercumulate and reservoir fluids from magmatic gravity currents. Only a thin seam of reservoir melt is captured by the base of the flow as it descends across the floor. Hence magmatic gravity currents, while producing modest amounts of crystal sorting, are not effective agents of mixing as lubrication and viscous forces inhibit interpenetration of reservoir fluid.
Life on the edge: African malaria mosquito (Anopheles gambiae s. l.) larvae are amphibious.
Miller, James R; Huang, Juan; Vulule, John; Walker, Edward D
2007-03-01
Anopheles gambiae s.l. is the main vector of malaria in Sub-Saharan Africa. Here, an estimated 1 million people die every year from this disease. Despite considerable research on An. gambiae that increasingly explores sub-organismal phenomena, important facets of the field biology of this deadly insect are yet being discovered. In the current study, we used simple observational tools to reveal that the habitat of larval An. gambiae is not limited within the boundaries of temporary mud puddles, as has been the accepted generalization. Thus, control tactics aimed at immatures must consider zones larger than puddles per se. In fact, eggs are more likely to be found outside than inside puddles. Eggs can develop and larvae can emerge on mud. Larvae are then capable of three distinct modes of terrestrial displacement (two active and one passive), whereby, they can reach standing water. On mud bearing a film of water, larvae actively displace backwards by sinusoidal undulations shown to be only a slight variation of the swimming motor program. On drying mud, larvae switch to a slower and forward form of active locomotion resembling that of a crawling caterpillar. During rains, small larvae may be passively displaced by flowing rainwater so as to be deposited into puddles. These capabilities for being amphibious, along with very rapid growth and development, help explain how An. gambiae thrives in a highly uncertain and often hostile larval environment.
Mud transportation on a steep shelf, Rio de La Plata shelf, Puerto Rico
Grove, K.A.; Pilkey, O.H.; Trumbull, J.V.A.
1982-01-01
Hurricanes David (August 29-30, 1979) and Frederick (September 2-5, 1979) caused major flooding of the Rio de La Plata in northern Puerto Rico. A thin mud layer was deposited across the narrow insular shelf adjacent to the river mouth. Within 5 months, fair-weather shelf-winnowing processes moved the mud layer entirely from the shelf, 0.5 to 2 km to the shelf break at the 50-m contour and beyond. The process of mud movement is termed 'mud hopping.' ?? 1982 A. M. Dowden, Inc.
Efficient retention of mud drives land building on the Mississippi Delta plain
NASA Astrophysics Data System (ADS)
Esposito, Christopher R.; Shen, Zhixiong; Törnqvist, Torbjörn E.; Marshak, Jonathan; White, Christopher
2017-07-01
Many of the world's deltas - home to major population centers - are rapidly degrading due to reduced sediment supply, making these systems less resilient to increasing rates of relative sea-level rise. The Mississippi Delta faces some of the highest rates of wetland loss in the world. As a result, multibillion dollar plans for coastal restoration by means of river diversions are currently nearing implementation. River diversions aim to bring sediment back to the presently sediment-starved delta plain. Within this context, sediment retention efficiency (SRE) is a critical parameter because it dictates the effectiveness of river diversions. Several recent studies have focused on land building along the open coast, showing SREs ranging from 5 to 30 %. Here we measure the SRE of a large relict crevasse splay in an inland, vegetated setting that serves as an appropriate model for river diversions. By comparing the mass fraction of sand in the splay deposit to the estimated sand fraction that entered it during its life cycle, we find that this mud-dominated sediment body has an SRE of ≥ 75 %, i.e., dramatically higher than its counterparts on the open coast. Our results show that transport pathways for mud are critical for delta evolution and that SRE is highly variable across a delta. We conclude that sediment diversions located in settings that are currently still vegetated are likely to be the most effective in mitigating land loss and providing long-term sustainability.
Sedimentation along the Eastern Chenier Plain Coast: Down Drift Impact of a Delta Complex Shift
NASA Technical Reports Server (NTRS)
Huh, Oscar K.; Walker, Nan D.; Moeller, Christopher
2001-01-01
The Mississippi River Chenier Plain is a shore parallel landform (down-drift from the Atchafalaya distributary of the Mississippi River) consisting of an alternating series of transgressive sand-shell ridges and regressive, progradational mudflats. The late 1940s shift of 1/3 of the flow of the Mississippi to the newly developing Atchafalaya delta complex to the west has resulted in injection of the river waters and suspended sediment into the westward flowing currents of the coastal current system. This has reactivated the dormant processes of mud accumulation along this coast. These environmental circumstances have provided the opportunity to: (1) investigate the depositional processes of the prograding, fine grained, mud flat facies of the open Chenier main coast and (2) to test the hypothesis that the impacts of the frequent cold front passages of fall, winter and spring exceed those of the occasional and more localized hurricane in shaping the coast and powering the dominant sedimentary processes. We conducted field investigations with the benefit of multi - scale, time series environmental surveillance by remote sensing systems, including airborne and satellite sensors. These systems provided invaluable new information on areal geomorphic patterns and the behavior of the coastal waters. This is a classic case of weather impacting inner shelf waters and sediments and causing the development of a new landform. It is clear that mud flats of the eastern chenier plain are prograding seaward, as well as progressively growing in a westerly direction.
Measurements in the bottom boundary layer on the Amazon subaqueous delta
Cacchione, D.A.; Drake, D.E.; Kayen, R.W.; Sternberg, R.W.; Kineke, G.C.; Tate, G.B.
1995-01-01
An instrumented bottom tripod (GEOPROBE) recorded flow and suspended sediment data in the bottom boundary layer above the lower foresets of the Amazon subaqueous delta in 65 m mean water depth in February, 1990. After about two weeks of operation the apparent seafloor at the tripod site rapidly elevated over a 14-hour period by about 44 cm. This sudden change, which was detected by an acoustic altimeter and which caused the loss of signals from the lowermost GEOPROBE current and optical sensors, is though to have been caused by the incursion of a dense bottom layer of fluid mud that migrated downslope from shallower sections of the foresets. The fluid-mud migration across the outer part of the foresets, if a repetitive and occasional process in this region, could be a major mechanism for episodic seaward growth of the delta. Current velocity profiles are used to estimate shear velocities, u*, and roughness lengths, zo, during the first two weeks of measurements. -from Authors
Flux and fate of Yangtze River sediment delivered to the East China Sea
NASA Astrophysics Data System (ADS)
Liu, J. P.; Xu, K. H.; Li, A. C.; Milliman, J. D.; Velozzi, D. M.; Xiao, S. B.; Yang, Z. S.
2007-03-01
Numerous cores and dating show the Yangtze River has accumulated about 1.16 × 10 12 t sediment in its delta plain and proximal subaqueous delta during Holocene. High-resolution seismic profiling and coring in the southern East China Sea during 2003 and 2004 cruises has revealed an elongated (˜ 800 km) distal subaqueous mud wedge extending from the Yangtze River mouth southward off the Zhejiang and Fujian coasts into the Taiwan Strait. Overlying what appears to be a transgressive sand layer, this distal clinoform thins offshore, from ˜ 40 m thickness between the 20 and 30 m water depth to < 1-2 m between 60 and 90 m water depth, corresponding to an across shelf distance of less than 100 km. Total volume of this distal mud wedge is about 4.5 × 10 11 m 3, equivalent to ˜ 5.4 × 10 11 t of sediment. Most of the sediment in this mud wedge comes from the Yangtze River, with some input presumably coming from local smaller rivers. Thus, the total Yangtze-derived sediments accumulated in its deltaic system and East China Sea inner shelf have amounted to about 1.7 × 10 12 t. Preliminary analyses suggest this longshore and across-shelf transported clinoform mainly formed in the past 7000 yrs after postglacial sea level reached its mid-Holocene highstand, and after re-intensification of the Chinese longshore current system. Sedimentation accumulation apparently increased around 2000 yrs BP, reflecting the evolution of the Yangtze estuary and increased land erosion due to human activities, such as farming and deforestation. The southward-flowing China Coastal Current, the northward-flowing Taiwan Warm Current, and the Kuroshio Current appear to have played critical roles in transporting and trapping most of Yangtze-derived materials in the inner shelf, and hence preventing the sediment escape into the deep ocean.
A helium-3/helium-4 dilution cryocooler for operation in zero gravity
NASA Technical Reports Server (NTRS)
Hendricks, John B.
1988-01-01
This research effort covered the development of He-3/He-4 dilution cryocooler cycles for use in zero gravity. The dilution cryocooler is currently the method of choice for producing temperatures below 0.3 Kelvin in the laboratory. However, the current dilution cryocooler depends on gravity for their operation, so some modification is required for zero gravity operation. In this effort, we have demonstrated, by analysis, that the zero gravity dilution cryocooler is feasible. We have developed a cycle that uses He-3 circulation, and an alternate cycle that uses superfluid He-4 circulation. The key elements of both cycles were demonstrated experimentally. The development of a true 'zero-gravity' dilution cryocooler is now possible, and should be undertaken in a follow-on effort.
NASA Astrophysics Data System (ADS)
Yoshida, T.; Sato, T.; Oyama, H.
2014-12-01
Methane hydrates in subsea environments near Japan are believed to new natural gas resources. These methane hydrate crystals are very small and existed in the intergranular pores of sandy sediments in sand mud alternate layers. For gas production, several processes for recovering natural gas from the methane hydrate in a sedimentary reservoir have been proposed, but almost all technique are obtain dissociated gas from methane hydrates. When methane hydrates are dissociated, gas and water are existed. These gas and water are flown in pore space of sand mud alternate layers, and there is a possibility that the mud layer is eroded by these flows. It is considered that the mad erosion causes production trouble such as making skins or well instability. In this study, we carried out pore scale numerical simulation to represent mud erosion. This research aims to develop a fundamental simulation method based on LBM (Lattice Boltzmann Method). In the simulation, sand particles are generated numerically in simulation area which is approximately 200x200x200μm3. The periodic boundary condition is used except for mud layers. The water/gas flow in pore space is calculated by LBM, and shear stress distribution is obtained at the position flow interacting mud surface. From this shear stress, we consider that the driving force of mud erosion. As results, mud erosion can be reproduced numerically by adjusting the parameters such as critical shear stress. We confirmed that the simulation using LBM is appropriate for mud erosion.
Radiological characterization of clay mixed red mud in particular as regards its leaching features.
Hegedűs, Miklós; Sas, Zoltán; Tóth-Bodrogi, Edit; Szántó, Tamás; Somlai, János; Kovács, Tibor
2016-10-01
The reuse of industrial by-products such as red mud is of great importance. In the case of the building material industry the reuse of red mud requires a cautious attitude, since the enhanced radionuclide content of red mud can have an effect on human health. The natural radionuclide content of red mud from the Ajka red mud reservoir and the clay sample from a Hungarian brick factory were determined by gamma spectrometry. It was found that maximum 27.8% red mud content can be added to fulfil the conditions of the EU-BSS. The effect of heat treatment was investigated on a red mud-clay mixture and it was found that in the case of radon and thoron exhalation the applied heat reduced remarkably the exhalation capacities. The leaching features of red mud and different mixtures were studied according to the MSZ-21470-50 Hungarian standard, the British CEN/TS 14429 standard and the Tessier sequential extraction method. The Tessier method and the MSZ-21470-50 standard are suitable for the characterization of materials; however, they do not provide enough information for waste deposition purposes. To this end, we propose using the CEN/TS 14429 method, because it is easy to use, and gives detailed information about the material's behaviour under different pH conditions, however, further measurements are necessary. Copyright © 2016 Elsevier Ltd. All rights reserved.
Couplings of gravitational currents with Chern-Simons gravities
NASA Astrophysics Data System (ADS)
Ertem, Ümit; Açık, Özgür
2013-02-01
The coupling of conserved p-brane currents with non-Abelian gauge theories is done consistently by using Chern-Simons forms. Conserved currents localized on p-branes that have a gravitational origin can be constructed from Killing-Yano forms of the underlying spacetime. We propose a generalization of the coupling procedure with Chern-Simons gravities to the case of gravitational conserved currents. In odd dimensions, the field equations of coupled Chern-Simons gravities that describe the local curvature on p-branes are obtained. In special cases of three and five dimensions, the field equations are investigated in detail.
NASA Astrophysics Data System (ADS)
Slack, John F.; Turner, Robert J. W.; Ware, Paul L. G.
1998-05-01
Large submarine mud volcanoes in the abyssal part of the Black Sea south of the Crimean Peninsula are similar in many respects to synsedimentary mud volcanoes in the Mesoproterozoic Belt-Purcell basin. One of the Belt-Purcell mud volcanoes directly underlies the giant Sullivan Pb-Zn-Ag deposit in southeastern British Columbia. Footwall rocks to the Sullivan deposit comprise variably tourmalinized siltstone, conglomerate, and related fragmental rock; local thin pyrrhotite-rich and spessartine-quartz beds are interpreted as Fe and Fe-Mn exhalites, respectively. Analogous Fe- and Mn-rich sediments occur near the abyssal Black Sea mud volcanoes. Massive pyrite crusts and associated carbonate chimneys discovered in relatively shallow waters (˜200 m depth) west of the Crimean Peninsula indicate an active sea-floor hydrothermal system. Subaerial mud volcanoes on the Kerch and Taman Peninsulas (˜100 km north of the abyssal mud volcanoes) contain saline thermal waters that locally have very high B contents (to 915 mg/L). These data suggest that tourmalinites might be forming in or near submarine Black Sea mud volcanoes, where potential may also exist for Sullivan-type Pb-Zn mineralization.
NASA Astrophysics Data System (ADS)
Muraleedharan, K. R.; Dinesh Kumar, P. K.; Prasanna Kumar, S.; Srijith, B.; John, Sebin; Naveen Kumar, K. R.
2017-04-01
Alappuzha mud bank draws special attention among the twenty-mud bank locations reported along the Kerala coast by its remoteness from riverine sources. Among several hypotheses proposed for the formation of mud bank, the subterranean hypothesis was most accepted because of the occurrence of low salinity in the bottom layers. The present study provides evidence to show that occurrence of low salinity waters near the bottom in the mud bank region is an artifact of measuring technique employed for the measurement of salinity. The usual technique of conductivity based salinity determination completely fails in the presence of water laden with high amount of suspended sediment. Laboratory experiments were conducted to determine the response of electrode and conductivity cell sensor types to determine the salinity using a range of suspended sediment in the water column. Actual sediment samples from the mud bank region were utilized for the above studies. Based on field observations and experiments, we conclude that the low salinity was the manifestation of the presence highly turbid fluid mud formation in the mud bank region rather than the influence of fresh water.
Mud Banks along the southwest coast of India are not too muddy for plankton.
Jyothibabu, R; Balachandran, K K; Jagadeesan, L; Karnan, C; Arunpandi, N; Naqvi, S W A; Pandiyarajan, R S
2018-02-07
Considering Alappuzha Mud Bank in the southern Kerala coast as a typical case of biologically productive Mud Banks that form along the southwest coast of India during the Southwest Monsoon (June - September), the present study addresses several pertinent missing links between the physical environment in Mud Banks and their influence on plankton stock. This study showed that very strong coastal upwelling prevails in the entire study domain during the Southwest Monsoon, which manifests itself in the form of significantly cool, hypoxic and nitrate-rich waters surfacing near the coast. The upwelled water persisting throughout the Southwest Monsoon period was found to have fuelled the exceptionally high phytoplankton stock in the entire study area, including the Mud Bank region. Having accepted that Mud Banks are special because of the calm sea surface conditions and relatively high turbidity level in the water column around them, the present study showed that except at points close to the sea bottom, turbidity level in the Alappuzha Mud Bank was below the critical level to inhibit the plankton stock. The suspended sediments that form in the Mud Bank occasionally could be attributed to the disturbance of the bottom fluid muddy layer and their vertical spurts.
Removal of hexavalent chromium by using red mud activated with cetyltrimethylammonium bromide.
Li, Deliang; Ding, Ying; Li, Lingling; Chang, Zhixian; Rao, Zhengyong; Lu, Ling
2015-01-01
The removal of hexavalent chromium [Cr(VI)] from aqueous solution by using red mud activated with cetyltrimethylammonium bromide (CTAB) was studied. The optimum operation parameters, such as CTAB concentration, pH values, contact time, and initial Cr(VI) concentration, were investigated. The best concentration of CTAB for modifying red mud was found to be 0.50% (mCTAB/VHCl,0.6 mol/L). The lower pH (<2) was found to be much more favourable for the removal of Cr(VI). Red mud activated with CTAB can greatly improve the removal ratio of Cr(VI) as high as four times than that of original red mud. Adsorption equilibrium was reached within 30 min under the initial Cr(VI) concentration of 100 mg L(-1). The isotherm data were analysed using Langmuir and Freundlich models. The adsorption of Cr(VI) on activated red mud fitted well to the Langmuir isotherm model, and the maximum adsorption capacity was estimated as 22.20 mg g(-1) (Cr/red mud). The adsorption process could be well described using the pseudo-second-order model. The result shows that activated red mud is a promising agent for low-cost water treatment.
Method and apparatus for optimizing determination of the originating depth of borehole cuttings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mc Auley, J.A.; Eppler, S.G.
1987-11-24
This patent describes a method for determining the arrival at the surface of an identifiable material from a predetermined drilling depth independent of pump stroke rate and intermittent operations during the utilization of at least a drill bit, a positive displacement mud pump and drilling mud during the drilling of a well. The method comprises the steps of: adding identifiable material to the drilling mud as the drilling mud is being pumped downwardly into the well; initiate count of the pump strokes of the positive displacement mud pump as the previous step occurs; observe arrival of the identifiable material atmore » the surface of the earth as the drilling mud exits from the well; observe the accumulated count of the pump strokes of the positive displacement mud pump which occur between step one and step three; subtract, from the accumulated count of the previous step, the number of pump strokes of the positive displacement mud pump required to pump the identifiable material down to the drill bit to establish a number of lag strokes; and utilize the number obtained in the previous step to identify the arrival of drill cuttings from a predetermined depth.« less
Slack, J.F.; Turner, R.J.W.; Ware, P.L.G.
1998-01-01
Large submarine mud volcanoes in the abyssal part of the Black Sea south of the Crimean Peninsula are similar in many respects to synsedimentary mud volcanoes in the Mesoproterozoic Belt-Purcell basin. One of the Belt-Purcell mud volcanoes directly underlies the giant Sullivan Pb-Zn-Ag deposit in southeastern British Columbia. Footwall rocks to the Sullivan deposit comprise variably tourmalinized siltstone, conglomerate, and related fragmental rock; local thin pyrrhotite-rich and spessartine-quartz beds are interpreted as Fe and Fe-Mn exhalites, respectively. Analogous Fe- and Mn-rich sediments occur near the abyssal Black Sea mud volcanoes. Massive pyrite crusts and associated carbonate chimneys discovered in relatively shallow waters (~200 m depth) west of the Crimean Peninsula indicate an active sea-floor-hydrothermal system. Subaerial mud volcanoes on the Kerch and Taman Peninsulas (~100 km north of the abyssal mud volcanoes) contain saline thermal waters that locally have very high B contents (to 915 mg/L). These data suggest that tourmalinites might be forming in or near submarine Black Sea mud volcanoes, where potential may also exist for Sullivan-type Pb-Zn mineralization.
NASA Astrophysics Data System (ADS)
Xu, Kehui; Sanger, Denise; Riekerk, George; Crowe, Stacie; Van Dolah, Robert F.; Wren, P. Ansley; Ma, Yanxia
2014-08-01
Beach nourishment has been a strategy widely used to slow down coastal erosion in many beaches around the world. The dredging of sand at the borrow site, however, can have complicated physical, geological and ecological impacts. Our current knowledge is insufficient to make accurate predictions of sediment infilling in many dredging pits due to lack of detailed sediment data. Two sites in the sandy shoal southeast of Port Royal Sound (PRS) of South Carolina, USA, were sampled 8 times from April 2010 to March 2013; one site (defined as 'borrow site') was 2 km offshore and used as the dredging site for beach nourishment of nearby Hilton Head Island in Beaufort County, South Carolina, and the other site (defined as 'reference site') was 10 km offshore and not directly impacted by the dredging. A total of 184 surficial sediment samples were collected randomly at two sites during 8 sampling periods. Most sediments were fine sand, with an average grain size of 2.3 phi and an organic matter content less than 2%. After the dredging in December 2011-January 2012, sediments at the borrow site became finer, changing from 1.0 phi to 2.3 phi, and carbonate content decreased from 10% to 4%; changes in mud content and organic matter were small. Compared with the reference site, the borrow site experienced larger variations in mud and carbonate content. An additional 228 sub-samples were gathered from small cores collected at 5 fixed stations in the borrow site and 1 fixed station at the reference site 0, 3, 6, 9, and 12 months after the dredging; these down-core sub-samples were divided into 1-cm slices and analyzed using a laser diffraction particle size analyzer. Most cores were uniform vertically and consisted of fine sand with well to moderately well sorting and nearly symmetrical averaged skewness. Based on the analysis of grain size populations, 2 phi- and 3 phi-sized sediments were the most dynamic sand fractions in PRS. Mud deposition on shoals offshore of PRS presumably happens when offshore mud transport is prevalent and there is a following rapid sand accumulation to bury the mud. However, in this borrow site there was very little accumulation of mud. This will allow the site to be used in future nourishment projects presuming no accumulation of mud occurs in the future.
Geochemical recovery of the Torna-Marcal river system after the Ajka red mud spill, Hungary.
Anton, Á D; Klebercz, O; Magyar, Á; Burke, I T; Jarvis, A P; Gruiz, K; Mayes, W M
2014-12-01
The failure of the Ajka red mud depository in October 2010 led to the largest single release of red mud into the surface water environment. This study provides a comparative assessment of stream sediment quality in the Torna-Marcal-Rába catchment between post-disaster surveys (2010) and follow up surveys at an identical suite of 21 locations in 2013. The signature of red mud apparent in initial surveys with high Al, As, Cr, Na, V was only apparent at a small number of sample stations in recent surveys. These constitute <1 km of stream, compared to the >20 km reach of affected sediments in the immediate aftermath of the spill. Concentrations of red mud-derived contaminants are predominately associated with fine fractions of the red mud (<8 μm). This enhances transport out of the system of red mud-derived contaminants and, along with extensive remedial efforts, has substantially limited the within-channel inventory of potentially ecotoxic metals and metalloids.
Calcification-carbonation method for red mud processing.
Li, Ruibing; Zhang, Tingan; Liu, Yan; Lv, Guozhi; Xie, Liqun
2016-10-05
Red mud, the Bayer process residue, is generated from alumina industry and causes environmental problem. In this paper, a novel calcification-carbonation method that utilized a large amount of the Bayer process residue is proposed. Using this method, the red mud was calcified with lime to transform the silicon phase into hydrogarnet, and the alkali in red mud was recovered. Then, the resulting hydrogarnet was decomposed by CO2 carbonation, affording calcium silicate, calcium carbonate, and aluminum hydroxide. Alumina was recovered using an alkaline solution at a low temperature. The effects of the new process were analyzed by thermodynamics analysis and experiments. The extraction efficiency of the alumina and soda obtained from the red mud reached 49.4% and 96.8%, respectively. The new red mud with <0.3% alkali can be used in cement production. Using a combination of this method and cement production, the Bayer process red mud can be completely utilized. Copyright © 2016 Elsevier B.V. All rights reserved.
Resources Management Strategy For Mud Crabs (Scylla spp.) In Pemalang Regency
NASA Astrophysics Data System (ADS)
Purnama Fitri, Aristi Dian; Boesono, Herry; Sabdono, Agus; Adlina, Nadia
2017-02-01
The aim of this research is to develop resources management strategies of mud crab (Scylla spp.) in Pemalang Regency. The method used is descriptive survey in a case study. This research used primary data and secondary data. Primary data were collected through field observations and in-depth interviews with key stakeholders. Secondary data were collected from related publications and documents issued by the competent institutions. SWOT Analysis was used to inventory the strengths, weaknesses, opportunities and threats. TOWS matrix was used to develop an alternative of resources management strategies. SWOT analysis was obtained by 6 alternative strategies that can be applied for optimization of fisheries development in Pemalang Regency. The strategies is the control of mud crab fishing gear, restricted size allowable in mud crab, control of mud crab fishing season, catch monitoring of mud crab, needs a management institutions which ensure the implementation of the regulation, and implementation for mud crab aquaculture. Each alternative strategy can be synergized to optimize the resources development in Pemalang Regency.
Eruption of a deep-sea mud volcano triggers rapid sediment movement.
Feseker, Tomas; Boetius, Antje; Wenzhöfer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R; Camilli, Richard; German, Christopher R; de Beer, Dirk
2014-11-11
Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Håkon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the mud volcano. Four major events triggered rapid sediment uplift of more than a metre in height, substantial lateral flow of muds at average velocities of 0.4 m per day, and significant emissions of methane and CO₂ from the seafloor.
Eruption of a deep-sea mud volcano triggers rapid sediment movement
Feseker, Tomas; Boetius, Antje; Wenzhöfer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R.; Camilli, Richard; German, Christopher R.; de Beer, Dirk
2014-01-01
Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Håkon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the mud volcano. Four major events triggered rapid sediment uplift of more than a metre in height, substantial lateral flow of muds at average velocities of 0.4 m per day, and significant emissions of methane and CO2 from the seafloor. PMID:25384354
NASA Astrophysics Data System (ADS)
Anthony, Edward; Brunier, Guillaume; Hiwat, Micheal; Bilo, Karin
2017-04-01
The 350-km long coast of Suriname is part of a unique system in the world characterized by large-scale muddy sedimentation and chenier development. The mud is organized into discrete banks migrating alongshore under the influence of waves and currents, separated by 'inter-bank' zones, where cheniers commonly form. Braamspunt beach is a fine example of an open-coast chenier between the mouths of the Maroni and the Suriname Rivers. The former is the primary sand source for the beach, whereas the latter, near which the presently subsisting remnant of the beach is situated, forms a downdrift sink zone for this chenier. Satellite images between 1987 and 2016 shows that Braamspunt beach has significantly shortened over this period. This process has resulted from much of the sand supply coming from updrift (the Maroni) being integrated into a chenier driven landward by waves over mangroves and becoming overwhelmed by a mud bank migrating between the Maroni and Suriname Rivers. Two ground (hydrodynamics, GPS) and drone-photogrammetry surveys in 2016 show that Braamspunt beach is characterized by clear-cut longshore morphodynamic variations reflecting between the 'source' and the 'sink' zones. This gradient is related to different updrift (approaching mud bank) and downdrift (approaches to the Suriname estuary) contexts. The northern sector comprised two elements: the leading edge of the mud bank where the existing chenier (former open beach) has been isolated from the sea by mud and fossilized inland, and the 'terrestrial' shoreline junction with the leading edge of the mud bank. The latter segment consisted of a narrow 150 m-long sandy chenier migrating landward as mud has gained ground, resulting in shortening of the beach. As the chenier migrated inland over back-beach stands of Avicennia germinans mangroves, it left in its wake a muddy foreshore with subsisting mangroves that were part of the muddy mangrove-colonized muddy plain. The southern sector also comprised two segments: a narrow, strongly eroding 1.7 km-long reflective beach, and a relatively large, accretionary 0.6 km-long downdrift beach segment that constituted the downdrift sink for sand transferred alongshore. The multi-decadal to recent evolution of Braamspunt beach thus shows a classical chenier beach that depends essentially on sand supply from the Maroni, but transport is not direct and continuous as one would expect on a classical open-ocean beach because the sand from the Maroni source transported alongshore by wave-induced drift is partially sequestered over more or less long periods of time (multi-decadal) by mud banks migrating westward towards Guyana. Sand availability is, thus, neither constant nor perennial on Braamspunt beach. In other words, this chenier beach does not function as a classical through-put source-to-sink (Maroni-Suriname) sediment cell, but as a potentially fragmented temporally and alongshore-variable cell. This has serious implications for the overall sediment budget of the beach and its sustainability. It also implies that sand mining, practised on a large-scale on this beach, which also serves as a major marine turtle-nesting site in Suriname, could endanger the future existence of this chenier beach.
NASA Astrophysics Data System (ADS)
Anthony, Edward J.; Gardel, Antoine; Proisy, Christophe; Fromard, François; Gensac, Erwan; Peron, Christina; Walcker, Romain; Lesourd, Sandric
2013-07-01
The morphology and sediment dynamics of the 1500 km-long coast of South America between the mouths of the Amazon and the Orinoco Rivers are largely dependent on the massive suspended-sediment discharge of the Amazon, part of which is transported alongshore as mud banks. These mud banks have an overwhelming impact on the geology, the geomorphology, the ecology and the economy of this coast. Although numerous field investigations and remote sensing studies have considerably enhanced our understanding of the dynamics of this coast over the last three decades, much still remains to be understood of the unique functional mechanisms and processes driving its evolution. Among the themes that we deem as requiring further attention three come out as fundamental. The first concerns the mechanisms of formation of individual mud banks from mud streaming on the shelf off the mouth of the Amazon. An unknown quantity of the fluid mud generated by offshore estuarine front activity is transported shoreward and progressively forms mud banks on the Amapá coast, Brazil. The volume of each mud bank can contain from the equivalent of the annual mud supply of the Amazon to several times this annual sediment discharge. The mechanisms by which individual banks are generated from the Amazon turbidity maximum are still to be elucidated. Areas of research include regional mesoscale oceanographic conditions and mud supply from the Amazon. The second theme is that of variations in rates of migration of mud banks, which influence patterns of coastal accretion. Research emphasis needs to be placed on the analysis of both regional meteorological-hydrodynamic forcing and distant Atlantic forcing, as well as on the hydrology of the large rivers draining the Guyana Shield. The rivers appear to generate significant offshore deflection of mud banks in transit alongshore, through a hydraulic-groyne effect. This may favour both muddy accretion on the updrift coast and downdrift mud liquefaction with probably lessened muddy deposition. The third theme concerns sand supply by the Guiana Shield rivers. The rare sand deposits are important in providing sites for human settlements and routes and for nesting by marine turtles. The limited presence of sand bodies on this coast may reflect 'mud blanketing', a hypothesis that requires verification through high-resolution seismic analyses of shelf deposits and coring operations. The large Guiana Shield rivers, especially in Surinam and Guyana, have supplied sand for the construction of significant bands of cheniers, probably enhanced by the afore-mentioned downdrift hydraulic-groyne effect on hindered mud deposition. In all the three themes of this future research agenda, two central elements are the sediment input of the rivers of the Amazon basin, starting with the massive mud supply from the Amazon catchment itself, followed by sand inputs by the Guiana Shield rivers and their river-mouth effects on mud banks.
Feasibility study for an innovative industrial red mud utilisation method.
Kounalakis, Petros; Aravossis, Konstantinos; Karayianni, ChS
2016-02-01
Red mud is a high volume industrial waste, and its management poses a unique challenge. For the utilisation of red mud, an economical, energy saving, environmental friendly and widely applicable method has been found. The proposed novel method is purely chemical, and achieves the recovery of all the oxides contained in red mud totally and transforms them into high value added products. The present work shows that an investment in an industrial plant, treating red mud and turning a toxic industrial waste in commercial products, is safe and viable. © The Author(s) 2015.
Non-self-similar viscous gravity currents
NASA Astrophysics Data System (ADS)
Sutherland, Bruce R.; Cote, Kristen; Hong, Youn Sub Dominic; Steverango, Luke; Surma, Chris
2018-03-01
Lock-release experiments are performed focusing upon the evolution of near-pure glycerol flowing into fresh water. If the lock height is sufficiently tall, the current is found to propagate for many lock lengths close to the speed predicted for energy-conserving moderately non-Boussinesq gravity currents. The current then slows to a near stop as the current head ceases to be elevated relative to its tail and the current as a whole forms a wedge shape. By contrast, an experiment of near-pure glycerol advancing under air exhibits the well-known slowing of the current such that the front position increases as a one-fifth power of time. The evolution of a viscous gravity current in water is also qualitatively different from that for a high-Reynolds number gravity current which transitions smoothly from a constant speed to self-similar to viscous regime. The reason a viscous gravity current flowing under water moves initially at near-constant speed is not due to a lubrication layer forming below the current. Rather it is due to the return flow of water into the lock establishing a current with an elevated head that is taller than the viscous boundary layer depth near the current nose. The flow near the top of the head advances to the nose where it comes into contact with the tank bottom. Meanwhile the ambient fluid is pushed up and over the head rather than being drawn underneath it. The front slows rapidly to a near stop as the head height reduces to that comparable to the boundary layer depth underneath the head. The initial speed and entrainment into the current are shown to depend upon the ratio, Rℓ, of the starting current height to the characteristic boundary layer depth. In particular, entrainment via the turbulent shear flow over the head is found to increase the volume by less than 10 % during its evolution if Rℓ≲10 but increases by as much as 100 % for high-Reynolds number gravity currents. A conceptual model is developed that captures the transition from an inertially driven current to its sudden near stop by viscous forces.
NASA Astrophysics Data System (ADS)
Stow, Dorrik A. V.; Shanmugam, Ganapathy
1980-01-01
A comparative study of the sequence of sedimentary structures in ancient and modern fine-grained turbidites is made in three contrasting areas. They are (1) Holocene and Pleistocene deep-sea muds of the Nova Scotian Slope and Rise, (2) Middle Ordovician Sevier Shale of the Valley and Ridge Province of the Southern Appalachians, and (3) Cambro-Ordovician Halifax Slate of the Meguma Group in Nova Scotia. A standard sequence of structures is proposed for fine-grained turbidites. The complete sequence has nine sub-divisions that are here termed T 0 to T 8. "The lower subdivision (T 0) comprises a silt lamina which has a sharp, scoured and load-cast base, internal parallel-lamination and cross-lamination, and a sharp current-lineated or wavy surface with 'fading-ripples' (= Type C etc. …)." (= Type C ripple-drift cross-lamination, Jopling and Walker, 1968). The overlying sequence shows textural and compositional grading through alternating silt and mud laminae. A convolute-laminated sub-division (T 1) is overlain by low-amplitude climbing ripples (T 2), thin regular laminae (T 3), thin indistinct laminae (T 4), and thin wipsy or convolute laminae (T 5). The topmost three divisions, graded mud (T 6), ungraded mud (T 7) and bioturbated mud (T 8), do not have silt laminae but rare patchy silt lenses and silt pseudonodules and a thin zone of micro-burrowing near the upper surface. The proposed sequence is analogous to the Bouma (1962) structural scheme for sandy turbidites and is approximately equivalent to Bouma's (C)DE divisions. The repetition of partial sequences characterizes different parts of the slope/base-of-slope/basin plain environment, and represents deposition from different stages of evolution of a large, muddy, turbidity flow. Microstructural detail and sequence are well preserved in ancient and even slightly metamorphosed sediments. Their recognition is important for determining depositional processes and for palaeoenvironmental interpretation.
NASA Astrophysics Data System (ADS)
Roux, Stanley; Porterfield, D. Marshall; Haque, Aeraj Ul; Bushart, Thomas
The vector of gravity sets the direction of polarized development of single spore cells of the fern Ceratopteris richardii after light initiates their germination. Gravity also sets the direction of a trans-cell calcium current, which enters the cell along its bottom and exits it from its top. The direction of this current predicts the subsequent direction of spore development, and blocking this current with calcium channel blockers randomizes the direction of subsequent development. Recently the laboratory of D. Marshall Porterfield (Purdue University) developed a microchip device that can measure the direction and magnitude of the trans-spore calcium current in real time. Our laboratory in collaboration with Porterfield's recently found that this current inverts rapidly when the cells are turned upside down and that the magnitude of the current rises and falls with the magnitude of the g-force when these cells are tested in parabolic flight on the DC-9 aircraft. We assume that the gravity-directed entry of calcium into these cells is through calcium channels and its exit is through calcium pumps. Here we report our studies of a calcium pump that is highly expressed in the spores during the period when gravity is setting the direction of the calcium current, and we describe pharmacological tests of the relative importance of calcium pumps in maintaining the calcium current and in controlling the direction of subsequent spore development. We found that inhibitors that block the activity of calcium pumps also greatly depress the trans-cell current, but, surprisingly, have little effect on the ability of gravity to set the direction of spore development. These results, in combination with earlier findings, indicate that the gravity-directed opening of calcium channels along the bottom of spore cells plays a more important role in directing subsequent spore development than the activity of calcium pumps, despite the importance of these pumps in maintaining the trans-cell calcium current. Supported by NASA grants NAG2-1586 and NAG10-295 to S. J. R.
Characterization of MUDENG, a novel anti-apoptotic protein
Choi, J-H; Lim, J-B; Wickramanayake, D D; Wagley, Y; Kim, J; Lee, H-C; Seo, H G; Kim, T-H; Oh, J-W
2016-01-01
MUDENG (Mu-2-related death-inducing gene, MuD) is revealed to be involved in cell death signaling. Astrocytes, the major glial cell type in the central nervous system, are a source of brain tumors. In this study, we examined MuD expression and function in human astroglioma cells. Stimulation of U251-MG cells with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resulted in a 40% decrease in cell viability and a 33% decrease in MuD protein levels, although not in MuD mRNA levels. To study the functional relevance of MuD expression, stable transfectants expressing high levels of MuD were generated. Stimulation of these transfectants with TRAIL resulted in enhanced cell survival (77% for stable and 46% for control transfectants). Depletion of MuD led to a marked reduction upon TRAIL stimulation in cell viability (22% in MuD-depleted cells and 54% in control cells). In addition, we observed that MuD depletion increased the susceptibility of the cells to TRAIL by enhancing the cleavage of caspase-3/-9 and BH3-interacting domain death agonist (Bid). A unique 25-kDa fragment of B-cell lymphoma 2 (Bcl-2) lacking BH4 was observed 60–180 min post TRAIL treatment in MuD-depleted cells, suggesting that Bcl-2 is converted from its anti-apoptotic form to the truncated pro-apoptotic form. Importantly, the TRAIL-mediated decrease in cell viability in MuD-depleted cells was abrogated upon Bid depletion, indicating that the role of MuD in apoptotic signaling takes place at the Bid and Bcl-2 junction. MuD localizes predominantly in the endoplasmic reticulum and partly in the mitochondria and its amounts are reduced 6 h post TRAIL stimulation, presumably via caspase-3-mediated MuD cleavage. Collectively, these results suggest that MuD, a novel signaling protein, not only possesses an anti-apoptotic function but may also constitute an important target for the design of ideal candidates for combinatorial treatment strategies for glioma cells. PMID:27136675
NASA Astrophysics Data System (ADS)
Corry-Saavedra, K.; Straub, S. M.; Bolge, L.; Schindlbeck, J. C.; Kutterolf, S.; Woodhead, J. D.
2015-12-01
Fallout tephra in marine sediment provide an excellent archive of explosive arc volcanism that can be directly related to the other parameters of climate change, such as ice volume data, IRD (ice-rafted debris) input, etc. Current studies are based on 'discrete' tephra beds, which are produced by major eruptions and visible with the naked eye. Yet the more common, but less explosive arc eruptions that are more continuous through time produce 'disperse' tephra, which is concealed by the non-volcanic host sediment and invisible to the eye. The proportion of disperse tephra in marine sediments is known to be significant and may be critical in elucidating potential synchronicity between arc volcanism and glacial cycles. We conducted a pilot study in young sediments of IODP Hole 1437B drilled at 31°47.3911'N and 139°01.5788'E at the rear-arc of the Izu Bonin volcanic arc. By means of δ18O (Vautravers, in revision), eleven climatic cycles are recorded in uppermost 120 meter of carbonate mud that is interspersed by cm-thick tephra fallout layers. We selected six tephra layers, ranging from 0.2 to 1.16 million years in age, and sampled those vertically, starting from carbonate mud below the basal contact throughout the typical gradational top into the carbonate mud above. From each tephra bed, volcanic particles (>125 micrometer) were handpicked. All other samples were powdered and leached in buffered acetic acid and hydroxylamine hydrochloride to remove the carbonate and authigenous fraction, respectively. Major and trace element abundances (except for SiO2) from all samples were determined by ICP-MS and ICP-OES methods. Strong binary mixing trends are revealed between the pure tephra end member, and detrital sediment component. The tephra is derived from the Izu Bonin volcanic front and rear-arc, while the sediment component is presumably transported by ocean surface currents from the East China Sea. Our data show that mixing proportions change systematically with sample percentage left after leaching and the stratigraphic position of sample, implying that the composition of the aluminosilicate fraction is an indicator of the percentage of disperse ash present in the carbonate mud. This data leave potential to investigate temporal trends. Our results are currently being refined with radiogenic isotope data.
Comparing the efficacy of mature mud pack and hot pack treatments for knee osteoarthritis.
Sarsan, Ayşe; Akkaya, Nuray; Ozgen, Merih; Yildiz, Necmettin; Atalay, Nilgun Simsir; Ardic, Fusun
2012-01-01
The objective of this study is to compare the efficacy of mature mud pack and hot pack therapies on patients with knee osteoarthritis. This study was designed as a prospective, randomized-controlled, and single-blinded clinical trial. Twenty-seven patients with clinical and radiologic evidence of knee osteoarthritis were randomly assigned into two groups and were treated with mature mud packs (n 15) or hot packs (n=12). Patients were evaluated for pain [based on the visual analog scale (VAS)], function (WOMAC, 6 min walking distance), quality of life [Short Form-36 (SF-36)], and serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and insulin-like growth factor-1 (IGF-1) at baseline, post-treatment, and 3 and 6~months after treatment. The mud pack group shows a significant improvement in VAS, pain, stifness, and physical function domains of WOMAC. The difference between groups of pain and physical activity domains is significant at post-treatment in favor of mud pack. For a 6 min walking distance, mud pack shows significant improvement, and the difference is significant between groups in favor of mud pack at post-treatment and 3 and 6 months after treatment. Mud pack shows significant improvement in the pain subscale of SF-36 at the third month continuing until the sixth month after the treatment. Significant improvements are found for the social function, vitality/energy, physical role disability, and general health subscales of SF-36 in favor of the mud pack compared with the hot pack group at post-treatment. A significant increase is detected for IGF-1 in the mud pack group 3 months after treatment compared with the baseline, and the difference is significant between groups 3 months after the treatment. Mud pack is a favorable option compared with hotpack for pain relief and for the improvement of functional conditions in treating patients with knee osteoarthritis.
Mud Flow Characteristics Occurred in Izuoshima Island, 2013
NASA Astrophysics Data System (ADS)
Takebayashi, H.; Egashira, S.; Fujita, M.
2015-12-01
Landslides and mud flows were occurred in the west part of the Izuoshima Island, Japan on 16 October 2013. The Izuoshima Island is a volcanic island and the land surface is covered by the volcanic ash sediment in 1m depth. Hence, the mud flow with high sediment concentration was formed. The laminar layer is formed in the debris flow from the bed to the fluid surface. On the other hand, the laminar flow is restricted near the bed in the mud flow and the turbulence flow is formed on the laminar flow layer. As a result, the equilibrium slope of the mud flow becomes smaller comparing to the debris flow. In this study, the numerical analysis mud flow model considering the effect of turbulence flow on the equilibrium slope of the mud flow is developed. Subsequently, the model is applied to the mud flow occurred in the Izuoshima Island and discussed the applicability of the model and the flow characteristics of the mud flow. The differences of the horizontal flow areas between the simulated results and the field data are compared and it was found that the outline of the horizontal shape of the flow areas is reproduced well. Furthermore, the horizontal distribution of the erosion and deposition area is reproduced by the numerical analysis well except for the residential area (Kandachi area). Kandachi area is judged as the erosion area by the field observation, but the sediment was deposited in the numerical analysis. It is considered that the 1.5hour heavy rain over 100mm/h after the mud flow makes the discrepancy. The difference of the horizontal distribution of the maximum flow surface elevation between the simulated results and the field data are compared and it was found that the simulated flow depth is overestimated slightly, because of the wider erosion area due to the coarse resolution elevation data. The averaged velocity and the depth of the mud flow was enough large to collapse the houses.
Multiphase modelling of mud volcanoes
NASA Astrophysics Data System (ADS)
Colucci, Simone; de'Michieli Vitturi, Mattia; Clarke, Amanda B.
2015-04-01
Mud volcanism is a worldwide phenomenon, classically considered as the surface expression of piercement structures rooted in deep-seated over-pressured sediments in compressional tectonic settings. The release of fluids at mud volcanoes during repeated explosive episodes has been documented at numerous sites and the outflows resemble the eruption of basaltic magma. As magma, the material erupted from a mud volcano becomes more fluid and degasses while rising and decompressing. The release of those gases from mud volcanism is estimated to be a significant contributor both to fluid flux from the lithosphere to the hydrosphere, and to the atmospheric budget of some greenhouse gases, particularly methane. For these reasons, we simulated the fluid dynamics of mud volcanoes using a newly-developed compressible multiphase and multidimensional transient solver in the OpenFOAM framework, taking into account the multicomponent nature (CH4, CO2, H2O) of the fluid mixture, the gas exsolution during the ascent and the associated changes in the constitutive properties of the phases. The numerical model has been tested with conditions representative of the LUSI, a mud volcano that has been erupting since May 2006 in the densely populated Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industry, farmland, and over 10,000 homes. The activity of LUSI mud volcano has been well documented (Vanderkluysen et al., 2014) and here we present a comparison of observed gas fluxes and mud extrusion rates with the outcomes of numerical simulations. Vanderkluysen, L.; Burton, M. R.; Clarke, A. B.; Hartnett, H. E. & Smekens, J.-F. Composition and flux of explosive gas release at LUSI mud volcano (East Java, Indonesia) Geochem. Geophys. Geosyst., Wiley-Blackwell, 2014, 15, 2932-2946
Gyarmati, Noémi; Kulisch, Ágota; Németh, András; Bergmann, Annamária; Horváth, József; Mándó, Zsuzsanna; Matán, Ágnes; Szakál, Erika; Sasné Péter, Tímea; Szántó, Dóra; Bender, Tamás
2017-03-01
Heat therapy is one of the most popular non-pharmacological treatments for osteoarthritis of the hand. To investigate the therapeutic and chemical effects of Hévíz mud on patients with hand osteoarthritis. We randomly assigned 47 patients with mild-to-moderate hand osteoarthritis to two groups. Patients in group 1 (n=23) received Hévíz mud applied directly to both hands, whereas patients in group 2 (n=24) also received mud to both hands, but nylon gloves separated the skin from the mud. Patients in both groups underwent five 20 minute treatment sessions per week for 3 weeks. The temperature of the mud was 42°C. Outcome measures were Visual Analogue Scale (VAS) scores, hand grip strength, the number of swollen and tender joints of the hand, the duration of morning joint stiffness, Health Assessment Questionnaire score, and EuroQoL Group 5-Dimension Self-Report Questionnaire score. The study parameters were evaluated at baseline, immediately after treatment, and after 16 weeks. Both groups showed improvement in nearly all assessed parameters at the end of treatment and at 16 weeks from the start of treatment. At the week 16 follow-up visit, the patient group directly treated with mud showed significantly better improvement in VAS for II and IV parameters and in swollen joint count in both hands compared to the nylon glove-mud group. Hévíz mud therapy significantly improved objective and subjective parameters in patients with hand osteoarthritis and had a beneficial effect on the patients' quality of life. Further studies are required to evaluate the chemical effects of the mud.
NASA Astrophysics Data System (ADS)
Loher, Markus; Ceramicola, Silvia; Wintersteller, Paul; Meinecke, Gerrit; Sahling, Heiko; Bohrmann, Gerhard
2018-02-01
Submarine mud volcanoes develop through the extrusion of methane-rich fluids and sediments onto the seafloor. The morphology of a mud volcano can record its extrusive history and processes of erosion and deformation affecting it. The study of offshore mud volcano dynamics is limited because only few have been mapped at resolutions that reveal their detailed surface structures. More importantly, rates and volumes of extruded sediment and methane are poorly constrained. The 100 m high twin cones of Venere mud volcano are situated at ˜1,600 m water depth within Squillace Canyon along the Ionian Calabrian margin, Mediterranean Sea. Seafloor bathymetry and backscatter data obtained by a ship-based system and an autonomous underwater vehicle (AUV) allow mapping of mudflow deposits of the mud volcano and bedforms in the surrounding canyon. Repeated surveying by AUV document active mud movement at the western summit in between 2014 and 2016. Through sediment coring and tephrochronology, ages of buried mudflow deposits are determined based on the sedimentation rate and the thickness of overlying hemipelagic sediments. An average extrusion rate of 27,000 m3/yr over the last ˜882 years is estimated. These results support a three-stage evolutionary model of Venere mud volcano since ˜4,000 years ago. It includes the onset of quiescence at the eastern cone (after ˜2,200 years ago), erosive events in Squillace Canyon (prior to ˜882 years ago), and mudflows from the eastern cone (since ˜882 years). This study reveals new interactions between a mud volcano and a canyon in the deep sea.
Effects of mud supply on large-scale estuary morphology and development over centuries to millennia
NASA Astrophysics Data System (ADS)
Braat, Lisanne; van Kessel, Thijs; Leuven, Jasper R. F. W.; Kleinhans, Maarten G.
2017-10-01
Alluvial river estuaries consist largely of sand but are typically flanked by mudflats and salt marshes. The analogy with meandering rivers that are kept narrower than braided rivers by cohesive floodplain formation raises the question of how large-scale estuarine morphology and the late Holocene development of estuaries are affected by cohesive sediment. In this study we combine sand and mud transport processes and study their interaction effects on morphologically modelled estuaries on centennial to millennial timescales. The numerical modelling package Delft3D was applied in 2-DH starting from an idealised convergent estuary. The mixed sediment was modelled with an active layer and storage module with fluxes predicted by the Partheniades-Krone relations for mud and Engelund-Hansen for sand. The model was subjected to a range of idealised boundary conditions of tidal range, river discharge, waves and mud input. The model results show that mud is predominantly stored in mudflats on the side of the estuary. Marine mud supply only influences the mouth of the estuary, whereas fluvial mud is distributed along the whole estuary. Coastal waves stir up mud and remove the tendency to form muddy coastlines and the formation of mudflats in the downstream part of the estuary. Widening continues in estuaries with only sand, while mud supply leads to a narrower constant width and reduced channel and bar dynamics. This self-confinement eventually leads to a dynamic equilibrium in which lateral channel migration and mudflat expansion are balanced on average. However, for higher mud concentrations, higher discharge and low tidal amplitude, the estuary narrows and fills to become a tidal delta.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Icerman, L.; Starkey, A.; Trentman, N.
1981-08-01
Magnetic, gravity, seismic-refraction, and seismic-reflection profiles across the Las Alturas Geothermal Anomaly, New Mexico, are presented. Studies in the Socorro area include the following: seismic measurements of the tertiary fill in the Rio Grande Depression west of Socorro, geothermal data availability for computer simulation in the Socorro Peak KGRA, and ground water circulation in the Socorro Geothermal Area. Regional geothermal exploration in the Truth or Consequences Area includes: geological mapping of the Mud Springs Mountains, hydrogeology of the thermal aquifer, and electrical-resistivity investigation of the geothermal potential. Other studies included are: geothermal exploration with electrical methods near Vado, Chamberino, andmore » Mesquite; a heat-flow study of Dona Ana County; preliminary heat-flow assessment of Southeast Luna County; active fault analysis and radiometric dating of young basalts in southern New Mexico; and evaluation of the geothermal potential of the San Juan Basin in northwestern New Mexico.« less
Evaluation of dredged material proposed for ocean disposal from Shark River Project area
DOE Office of Scientific and Technical Information (OSTI.GOV)
Antrim, L.D.; Gardiner, W.W.; Barrows, E.S.
1996-09-01
The objective of the Shark River Project was to evaluate proposed dredged material to determine its suitability for unconfined ocean disposal at the Mud Dump Site. Tests and analyses were conducted on the Shark River sediments. The evaluation of proposed dredged material consisted of bulk sediment chemical and physical analysis, chemical analyses of dredging site water and elutriate, water-column and benthic acute toxicity tests, and bioaccumulation tests. Individual sediment core samples collected from the Shark River were analyzed for grain size, moisture content, and total organic carbon (TOC). One sediment composite was analyzed for bulk density, specific gravity, metals, chlorinatedmore » pesticides, polychlorinated biphenyl (PCB) congeners, polynuclear aromatic hydrocarbons (PAHs), and 1,4- dichlorobenzene. Dredging site water and elutriate, prepared from suspended-particulate phase (SPP) of the Shark River sediment composite, were analyzed for metals, pesticides, and PCBs. Benthic acute toxicity tests and bioaccumulation tests were performed.« less
Recent performance of the dual-resistivity MWD tool
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wagstaff, J.D.; Grupping, T.I.F.
1990-06-01
This article reports on the dual-resistivity MWD tool, which uses section of the drill collar as electrodes and provides two independent resistivity measurements: a principal well-focused lateral measurement of the current flowing radially from a defined segment of the drill collar and a secondary axial or bit measurement of the current flowing from a defined portion of the lower bottomhole assembly (BHA). In oil-based muds, a single (bit) measurement is made of the current flowing to the formation through the drill bit.
Present Practice of Using Nautical Depth to Manage Navigation Channels in the Presence of Fluid Mud
2017-05-01
material surfaces cannot be interpreted reliably unless other correlating information is developed. Surveying of fluid mud properties. At some locations...depth to manage navigation channels and ports requires a mud property that determines a navigability criteria, a practical method for surveying that...for managing navigation channels, (3) issues related to conducting hydrographic surveying in waterways with fluid mud bottoms, (4) the newest
Feasibility of co-reduction roasting of a saprolitic laterite ore and waste red mud
NASA Astrophysics Data System (ADS)
Wang, Xiao-ping; Sun, Ti-chang; Kou, Jue; Li, Zhao-chun; Tian, Yu
2018-06-01
Large scale utilization is still an urgent problem for waste red mud with a high content of alkaline metal component in the future. Laterite ores especially the saprolitic laterite ore are one refractory nickel resource, the nickel and iron of which can be effectively recovered by direct reduction and magnetic separation. Alkaline metal salts were usually added to enhance reduction of laterite ores. The feasibility of co-reduction roasting of a saprolitic laterite ore and red mud was investigated. Results show that the red mud addition promoted the reduction of the saprolitic laterite ore and the iron ores in the red mud were co-reduced and recovered. By adding 35wt% red mud, the nickel grade and recovery were 4.90wt% and 95.25wt%, and the corresponding iron grade and total recovery were 71.00wt% and 93.77wt%, respectively. The X-ray diffraction (XRD), scanning electron microscopy, and energy dispersive spectroscopy (SEM-EDS) analysis results revealed that red mud addition was helpful to increase the liquid phase and ferronickel grain growth. The chemical compositions "CaO and Na2O" in the red mud replaced FeO to react with SiO2 and MgSiO3 to form augite.
Xu, Hai-Dong; Su, Hong-Jun; Zou, Wei-Bin; Liu, Shan-Shan; Yan, Wen-Rui; Wang, Qian-Qian; Yuan, Li-Li; Chan, Siuming Francis; Yu, Xiao-Qiang; He, Jian-Guo; Weng, Shao-Ping
2015-05-01
Mud crab reovirus (MCRV) is the causative agent of a severe disease in cultured mud crab (Scylla paramamosain), which has caused huge economic losses in China. MCRV is a double-stranded RNA virus with 12 genomic segments. In this paper, SDS-PAGE, mass spectrometry and Western blot analyses revealed that the VP12 protein encoded by S12 gene is a structural protein of MCRV. Immune electron microscopy assay indicated that MCRV VP12 is a component of MCRV outer shell capsid. Yeast two hybrid cDNA library of mud crab was constructed and mud crab voltage-dependent anion-selective channel (mcVDAC) was obtained by MCRV VP12 screening. The full length of mcVDAC was 1180 bp with an open reading frame (ORF) of 849 bp encoding a 282 amino acid protein. The mcVDAC had a constitutive expression pattern in different tissues of mud crab. The interaction between MCRV VP12 and mcVDAC was determined by co-immunoprecipitation assay. The results of this study have provided an insight on the mechanisms of MCRV infection and the interactions between the virus and mud crab. Copyright © 2015 Elsevier Ltd. All rights reserved.
Radiochemical analysis of waters and mud of Euganean spas (Padua)
NASA Astrophysics Data System (ADS)
Cantaluppi, C.; Fasson, A.; Ceccotto, F.; Cianchi, A.; Degetto, S.
2012-04-01
The area around the Euganean Hills (North-East Italy) is concerned with thermal phenomena known and used for therapeutic purposes since ancient times. The thermal waters collected in this area have taken up a natural radionuclides content due to the leaching of hot and permeable deep rocks, with which they come into contact, before their rising to the surface. During the "maturation" process of the mud used for treatment purposes, the thermal waters make happen a complex series of biochemical changes and release a series of chemical species to the mud, resulting, in particular, in an enrichment phenomenon for some radionuclides. In this work, the first radiochemical analysis extended to all the Euganean Thermal District is reported. In particular, chemical analyses of mud, as well as radiochemical analyses of both mud and waters were performed; the enrichment of the radioisotopes in mud used for treatments was also documented. The results show that the 226Ra content in mud, during the "maturation" process, presents an enrichment even of one order of magnitude with respect to the value found in the unprocessed mud. Furthermore, in the same thermal waters, high concentrations of "unsupported" 222Rn have been found, which have shown to be not completely negligible both for people under treatment and particularly for spa workers.
40 CFR 147.2902 - Definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... loss of drilling mud into porous ground, or to prevent water, gas, or other fluid from entering the...: (a)(1) Which supplies any public water system; or (2) Which contains a sufficient quantity of ground water to supply a public water system; and (i) Currently supplies drinking water for human consumption...
NASA Astrophysics Data System (ADS)
Worster, Grae; Huppert, Herbert; Robison, Rosalyn; Nandkishore, Rahul; Rajah, Luke
2008-11-01
We have used simple laboratory experiments with viscous fluids to explore the dynamics of grounding lines between Antarctic marine ice sheets and the freely floating ice shelves into which they develop. Ice sheets are shear-dominated gravity currents, while ice shelves are extensional gravity currents with zero shear to leading order. Though ice sheets have non-Newtonian rheology, fundamental aspects of their flow can be explored using Newtonian fluid mechanics. We have derived a mathematical model of this flow that incorporates a new dynamic boundary condition for the position of the grounding line, where the gravity current loses contact with the solid base. Good agreement between our theoretical predictions and our experimental measurements, made using gravity currents of syrup flowing down a rigid slope into a deep, dense salt solution, gives confidence in the fundamental assumptions of our model, which can be incorporated into shallow-ice models to make important predictions regarding the dynamical stability of marine ice sheets.
The Dead Sea Mud and Salt: A Review of Its Characterization, Contaminants, and Beneficial Effects
NASA Astrophysics Data System (ADS)
Bawab, Abeer Al; Bozeya, Ayat; Abu-Mallouh, Saida; Abu Irmaileh, Basha'er; Daqour, Ismail; Abu-Zurayk, Rund A.
2018-02-01
The Dead Sea has been known for its therapeutic and cosmetic properties. The unique climatic conditions in the Dead Sea area make it a renowned site worldwide for the field of climatotherapy, which is a natural approach for the provision of medications for many human diseases including unusual exclusive salt composition of the water, a special natural mud, thermal mineral springs, solar irradiation, oxygen-rich and bromine-rich haze. This review focuses on the physical, chemical, and biological characteristics of the Dead Sea mud and salts, in addition to their contaminants, allowing this review to serve as a guide to interested researchers to their risks and the importance of treatment. Beneficial effects of Dead Sea mud and salts are discussed in terms of therapy and cosmetics. Additional benefits of both Dead Sea mud and salts are also discussed, such as antimicrobial action of the mud in relation to its therapeutic properties, and the potency of mud and salts to be a good medium for the growth of a halophilic unicellular algae, used for the commercial production of β-carotene Dunaliella.
Aydin, Senar
2016-12-01
The aim of this study was to investigate the usability of magnetic Fe3O4/red mud nanoparticles (NPs) for the removal of organophosphorus pesticides from water samples. The effect of various experimental parameters such as red mud amount in Fe3O4/red mud-NPs, pH, contact time, initial pesticide concentrations and adsorbent dose was studied in order to find the optimum conditions for their removal in a batch process. The Fe3O4/red mud-NPs were characterized by using TGA, SEM, XRD, VSM, and determination of the BET surface area. After the regenerated Fe3O4/red mud-NPs were used three times, the sorption capacity and the magnetic separability were observed to be unaffected. Freundlich model described the sorption process better than Langmuir isotherm and the pseudo second-order kinetic model was determined as the best-fit model. The film diffusion mechanism was found to be a main rate control mechanism. The Fe3O4/red mud-NPs satisfactorily removed the OPPS from real water samples.
Radiological restrictions of using red mud as building material additive.
Gu, Hannian; Wang, Ning; Liu, Shirong
2012-09-01
Red mud remains as residue from the processing of bauxite using different methods. The chemical composition of red mud varies widely with respect to the types of bauxite ore and processing parameters. Red mud samples from Guizhou, China, were investigated using a X-ray fluorescence spectroscope, a quadrupole inductively coupled plasma mass spectrometer and a electron probe micro-analyzer. The results showed that red mud consisted of eight main chemical components--CaO, Al(2)O(3), SiO(2), Fe(2)O(3), TiO(2), Na(2)O, K(2)O and MgO--and dozens of trace elements, including natural radioactive elements, such as uranium and thorium. Gamma spectrometric analysis showed that the values of internal exposure index I (Ra) and external exposure index I (γ) of Guizhou red mud were 1.1-2.4 and 2.3-3.5 respectively. Thus, it should not be used as a main building material indiscriminately. The amount of red mud from Guizhou when it is used for main building materials in China should be less than 28-44%.
Utilization of drilling cuttings with extraction of ground for recultivation of disturbed soils
NASA Astrophysics Data System (ADS)
Gaevaya, E. V.; Bogaychuk, Y. E.; Tarasova, S. S.; Skipin, L. N.; Zakharova, E. V.
2017-10-01
Drilling of wells is connected with formation of the bore mud represented by the drill cutting with waste drilling mud. Bore mud has negative physical-chemical, physical and chemical properties: high content of salts, increased alkalinity, ash structure, soil overcrust, low airing, weak filterability and so on. In case of phosphogypsum adding to the bore mud, pH level decreases from the alkaline (10.5 U) to weakly alkaline 7.6 U, decrease of pH is connected with the influence of phosphogypsum acidity and neutralization of the more mud. Concentration of chloride ions and sulphate ions in reclaimed bore mud was 70±7 and 456±46 correspondingly. Presence of oil products in received soil was 198.0-219.0 mg/kg. When adding phosphogypsum, sand, sorbent and humic formulation «Rostok» to the bore mud, it has shown good germinating ability of cultures- phytomeliorants (93,3%). 100% germinating ability was observed in meadow grass with a height of overground sprouts 10.7 cm, germinating ability of red fescue was 80% with height of overground sprouts 9.6 cm.
Studying molecular changes during gravity perception and response in a single cell.
Cannon, Ashley E; Salmi, Mari L; Bushart, Thomas J; Roux, Stanley J
2015-01-01
Early studies revealed a highly predictable pattern of gravity-directed growth and development in Ceratopteris richardii spores. This makes the spores a valuable model system for the study of how a single cell senses and responds to the force of gravity. Gravity regulates both the direction and magnitude of a trans-cell calcium current in germinating spores, and the orientation of this current predicts the polarization of spore development. Molecular techniques have been developed to evaluate the transcriptomic and proteomic profiles of spores before and after gravity establishes the polarity of their development. Here we describe these techniques, along with protocols for sterilizing the spores, sowing them in a solid or liquid growth media, and evaluating germination.
NASA Astrophysics Data System (ADS)
Um, I. K.; Choi, M. S.
2017-12-01
The central South Sea mud (CSSM) is located between the Heuksan mud belt (HMB) in the Yellow Sea and Korea Strait shelf mud (KSSM) in the East Sea and developed along the eastward transport pathway in the South Sea. Major elements (Al, Fe, Mg, and Ti), trace elements (Li, Cs, Sc, and Rb), and rare earth elements (REEs) in the fine-grained sediments (<15 μm) of thirty-two surface sediment samples on the CSSM were analyzed to determine the fine-grained sediment provenance. The spatial distribution of the analyzed elements showed a clear separation of the western (W-CSSM) and eastern (E-CSSM) regions of the CSSM. Concentrations of Fe, Ti, Mg, Sc, and REEs were higher in the W-CSSM, whereas concentrations of Al, Cs, Li, and Rb were higher in the E-CSSM. The ratios of trace metals ((Cs+Sc)/Li and Rb/Li) can be successfully used as a provenance indicator in the study area but REEs compositions could not be used to track the provenance of fine-grained sediments because of a grain size effect. The mixing relationships of the provenance indicators showed that the fine-grained sediments of the CSSM comprise a mixture of the sediments discharged from the Seomjin River (SRS) and sediments eroded and transported from the Heuksan mud belt (HMBS) area by the Korean coastal current. Sediments originating from the HMB were deposited mostly in the W-CSSM, whereas those from the Seomjin River were deposited mostly in the E-CSSM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mark Krauss
2010-07-01
This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 544, Cellars, Mud Pits, and Oil Spills, identified in the Federal Facility Agreement and Consent Order (FFACO). Corrective Action Unit 544 comprises the following 20 corrective action sites (CASs) located in Areas 2, 7, 9, 10, 12, 19, and 20 of the Nevada Test Site (NTS): • 02-37-08, Cellar & Mud Pit • 02-37-09, Cellar & Mud Pit • 07-09-01, Mud Pit • 09-09-46, U-9itsx20 PS #1A Mud Pit • 10-09-01, Mud Pit • 12-09-03, Mud Pit • 19-09-01, Mudmore » Pits (2) • 19-09-03, Mud Pit • 19-09-04, Mud Pit • 19-25-01, Oil Spill • 19-99-06, Waste Spill • 20-09-01, Mud Pits (2) • 20-09-02, Mud Pit • 20-09-03, Mud Pit • 20-09-04, Mud Pits (2) • 20-09-06, Mud Pit • 20-09-07, Mud Pit • 20-09-10, Mud Pit • 20-25-04, Oil Spills • 20-25-05, Oil Spills This plan provides the methodology for field activities needed to gather the necessary information for closing each CAS. There is sufficient information and process knowledge from historical documentation and investigations of similar sites regarding the expected nature and extent of potential contaminants to recommend closure of CAU 544 using the SAFER process. Using the approach approved for previous mud pit investigations (CAUs 530–535), 14 mud pits have been identified that • are either a single mud pit or a system of mud pits, • are not located in a radiologically posted area, and • have no evident biasing factors based on visual inspections. These 14 mud pits are recommended for no further action (NFA), and further field investigations will not be conducted. For the sites that do not meet the previously approved closure criteria, additional information will be obtained by conducting a field investigation before selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible recommendation for closure of the remaining CASs in CAU 544. This will be presented in a closure report (CR) that will be prepared and submitted to the Nevada Division of Environmental Protection (NDEP) for review and approval. The sites will be investigated based on the data quality objectives (DQOs) developed on April 27, 2010, by representatives of NDEP and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO). The DQO process was used to identify and define the type, amount, and quality of data needed to determine and implement appropriate corrective actions for each CAS in CAU 544. The DQO process developed for this CAU identified the following expected closure options: (1) investigation and confirmation that no contamination exists above the final action levels (FALs) leading to an NFA declaration, (2) characterization of the nature and extent of contamination leading to closure in place with use restrictions, (3) clean closure by remediation and verification, (4) closure in place with use restrictions with no investigation if CASs are in crater areas that have been determined to be unsafe to enter, or (5) NFA if the mud pit CAS meets the criteria established during the CAUs 530–535 SAFER investigation. The following summarizes the SAFER activities that will support the closure of CAU 544: • Perform visual inspection of all CASs. • Perform site preparation activities (e.g., utilities clearances, construction of temporary site exclusion zones). • Removal of easily managed, nonhazardous, and nonradioactive debris, including vegetation (e.g., tumbleweeds), at various CASs that interfere with sampling, if required to inspect soil surface or collect soil sample. • Collect environmental samples from designated target populations (e.g., mud pits, cellars, stained soil) to confirm or disprove the presence of contaminants of concern (COCs) as necessary to supplement existing information. • If no COCs are present at a CAS, establish NFA as the corrective action. • If COCs exist, collect environmental samples from designated target populations (e.g., clean soil adjacent to contaminated soil) and submit for laboratory analyses to define the extent of COC contamination. • If a COC is present at a CAS, either - Establish clean closure as the corrective action. The material to be remediated will be removed, disposed of as waste, and verification samples will be collected from remaining soil, or - Establish closure in place as the corrective action and implement the appropriate use restrictions. • Confirm the preferred closure option is sufficient to protect human health and the environment.« less
Broadband Scattering from Sand and Sand/Mud Sediments with Extensive Environmental Characterization
2015-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Broadband Scattering from Sand and Sand/ Mud Sediments...TERM GOALS To model the effects of volume heterogeneities, both discrete and continuous, in scattering from sand and mud sediments. A better...IMP2 has been used extensively during TREX13 and BayEx14 to measure the porosity in both sand and mud sediments. Analysis of this recent data inspired a
New technology of extracting the amount of rare earth metals from the red mud
NASA Astrophysics Data System (ADS)
Martoyan, G. A.; Karamyan, G. G.; Vardan, G. A.
2016-01-01
The paper outlined the environmental and economic problems associated with red mud - the waste generated in processing of bauxite ore for aluminum production. The chemical analysis of red mud has identified a number of useful elements including rare earth metals. The electromembrane technology of red mud processing with extraction of valuable elements is described. A possible scheme of separation of these metals through electrolysis is also given.
Characterization of a Mud Deposit Offshore of the Patos Lagoon, Southern Brazil
2009-02-01
Journal Article 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Characterization of mud deposit offshore of the Patos lagoon, southern Brazil 5a...deposition of mud on the beach along the shoreface of Rio Grande do Sul, Brazil dramatically influences the normal operations in the littoral zone...Continental Shelf Research journal homepage: www.elsevier.com/locate/csr Characterization of a mud deposit offshore of the Patos Lagoon, southern Brazil
Bioleaching of rare earth and radioactive elements from red mud using Penicillium tricolor RM-10.
Qu, Yang; Lian, Bin
2013-05-01
The aim of this work is to investigate biological leaching of rare earth elements (REEs) and radioactive elements from red mud, and to evaluate the radioactivity of the bioleached red mud used for construction materials. A filamentous, acid-producing fungi named RM-10, identified as Penicillium tricolor, is isolated from red mud. In our bioleaching experiments by using RM-10, a total concentration of 2% (w/v) red mud under one-step bioleaching process was generally found to give the maximum leaching ratios of the REEs and radioactive elements. However, the highest extraction yields are achieved under two-step bioleaching process at 10% (w/v) pulp density. At pulp densities of 2% and 5% (w/v), red mud processed under both one- and two-step bioleaching can meet the radioactivity regulations in China. Copyright © 2013 Elsevier Ltd. All rights reserved.
Mud volcanoes of trinidad as astrobiological analogs for martian environments.
Hosein, Riad; Haque, Shirin; Beckles, Denise M
2014-10-13
Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil's Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region.
Mud Volcanoes of Trinidad as Astrobiological Analogs for Martian Environments
Hosein, Riad; Haque, Shirin; Beckles, Denise M.
2014-01-01
Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil’s Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region. PMID:25370529
“Can LUSI be stopped? - A case study and lessons learned from the relief wells”
NASA Astrophysics Data System (ADS)
Sutrisna, E.
2009-12-01
Since May 2006, in East Java, Indonesia, the LUSI mud volcano has been erupting huge volumes of mixture of predominately mud and water, with little sign of slowing down. It has disrupted social and economic life in this highly populated region. Most geologists believe LUSI is a naturally-occurring mud volcano (MV), like other MV in the Java island of particular interest are the MV along the Watukosek fault, such as, Kalang Anyar, Pulungan, Gunung Anyar, and Socah MV. All of these MV lie in the vicinity of the SSW/NNE trending Watukosek fault that passes through LUSI. The Porong collapse structure is an ancient MV closest to LUSI approx. 7 km away, which on seismic sections demonstrate its complex multi-branching plumbing system. Assuming that the mudflow passed through the wellbore due to an underground blowout, relief wells (RW) were planned to kill the mudflow and carried out in 3 stages, these were: 1. Re-entering the original Banjarpanji-1 (BJP-1) well to obtain accurate survey data so the relief wells could be steered into intersect this original well. 2. Drilling a monitoring well (M-1) to ascertain whether the soil had sufficient strength to support relief wells. 3. Drilling RW-1 and RW-2. Both RW-1 and RW-2 suffered of surface and subsurface problems never achieved their objectives and had to be aborted. Numbers of good lessons were learned from the relief well initiative, such as: 1. No gas or liquid flowed from the wellhead area when it was excavated one month after the eruption started. The wellhead remained intact and totally dead suggesting that the mud flowed to surface through a fault zone or a fracture network instead of up the wellbore. 2. The ‘fish’ in BJP-1 wellbore was found at its original location and not eroded away. This suggests that the mud flow did not pass through the wellbore. 3. The Temperature log showed lower temp. than surface mud temp. The Sonan log response was quiet. These results suggest that there was no near casing mudflow. 4. Dynamic subsurface conditions of the area with shear movement at a depth of 1,100 ft to 1,500 ft. 5. The RW-1 experienced alternate loss and kicks at a depth of around 3,200 ft. as it entered the unstable fault zone and fracture network which likely served as the mud flow conduit. Drilling in the zone of instability around the mudflow conduit cannot be avoided and is full of hazards. 6. The area suffers a dynamic geological condition. The subsidence rate at the rig site of more than 100 cm in a month. The subsidence also had a lateral component. 7. LUSI has multiple mudflow conduits as reflected in the more than 100 gas bubbles currently occurring within a radius of 1.5 km. Although the relief wells did not achieve their intended purpose to stop the mudflow, they allowed the collection of valuable data, all of which suggests that the mudflow did not originate from the BJP-1 wellbore as originally assumed. The use of relief wells to kill the mudflow is a futile attempt since in such complex plumbing system. New conduits or the two dormant mudflow centers along the fault line that appeared at the beginning of LUSI may reactivate if the currently active conduit is blocked. In conclusion, LUSI appears to be another naturally occurring MV that is impossible to kill using relief wells.
NASA Astrophysics Data System (ADS)
Tripsanas, E. K.; Bryant, W. R.; Prior, D. B.
2003-04-01
A large number of Jumbo Piston cores (up to 20 m long), acquired from the continental slope and rise of the Northwest Gulf of Mexico (Bryant Canyon area and eastern Sigsbee Escarpment), have recovered various mass-transport deposits. The main cause of slope instabilities over these areas is oversteepening of the slopes due to the seaward mobilization of the underlying allochthonous salt masses. Cohesive flow deposits were the most common recoveries in the sediment cores. Four types of cohesive flow deposits have been recognized: a) fluid debris flow, b) mud flow, c) mud-matrix dominated debris flow, and d) clast-dominated debris flow deposits. The first type is characterized by its relatively small thickness (less than 1 m), a mud matrix with small (less than 0.5 cm) and soft mud-clasts, and a faint layering. The mud-clasts reveal a normal grading and become more abundant towards the base of each layer. That reveals that their deposition resulted by several successive surges/pulses, developed in the main flow, than the sudden “freezing” of the whole flow. The main difference between mud flow and mud-matrix dominated debris flow deposits is the presence of small to large mud-clasts in the later. Both deposits consist of a chaotic mud-matrix, and a basal shear laminated zone, where the strongest shearing of the flow was exhibited. Convolute laminations, fault-like surfaces, thrust faults, and microfaults are interpreted as occurring during the “freezing” of the flows and/or by adjustments of the rested deposits. Clast-dominated debris flow deposits consist of three zones: a) an upper plug-zone, characterized by large interlocked clasts, b) a mid-zone, of higher reworked, inversely graded clasts, floating in a mud-matrix, and c) a lower shear laminated zone. The structure of the last three cohesive flow deposits indicate that they represent deposition of typical Bingham flows, consisting of an upper plug-zone in which the yield stress is not exceeded and an underlain shearing zone, where the shear stress exceeded the yield strength of the sediments. Mud-matrix, and clast-dominated debris flow deposits are the pervasive ones. Intensely sheared thin layers (5- to 20 cm) with sharp bases, displayed as successive layers at the base of mud/debris flow deposits, or as isolated depositional units interbedded in hemipelagic sediments, are as interesting, as enigmatic. They are interpreted as basal self-lubricating layers, of having high shear stress and pore pressures, over which the mud/debris flows were able to travel for very long distances.
Liu, Shanshan; Chen, Guanxing; Xu, Haidong; Zou, Weibin; Yan, Wenrui; Wang, Qianqian; Deng, Hengwei; Zhang, Heqian; Yu, Guojiao; He, Jianguo; Weng, Shaoping
2017-01-01
Mud crab (Scylla paramamosain) is an economically important marine cultured species in China's coastal area. Mud crab reovirus (MCRV) is the most important pathogen of mud crab, resulting in large economic losses in crab farming. In this paper, next-generation sequencing technology and bioinformatics analysis are used to study transcriptome differences between MCRV-infected mud crab and normal control. A total of 104.3 million clean reads were obtained, including 52.7 million and 51.6 million clean reads from MCRV-infected (CA) and controlled (HA) mud crabs respectively. 81,901, 70,059 and 67,279 unigenes were gained respectively from HA reads, CA reads and HA&CA reads. A total of 32,547 unigenes from HA&CA reads called All-Unigenes were matched to at least one database among Nr, Nt, Swiss-prot, COG, GO and KEGG databases. Among these, 13,039, 20,260 and 11,866 unigenes belonged to the 3, 258 and 25 categories of GO, KEGG pathway, and COG databases, respectively. Solexa/Illumina's DGE platform was also used, and about 13,856 differentially expressed genes (DEGs), including 4444 significantly upregulated and 9412 downregulated DEGs were detected in diseased crabs compared with the control. KEGG pathway analysis revealed that DEGs were obviously enriched in the pathways related to different diseases or infections. This transcriptome analysis provided valuable information on gene functions associated with the response to MCRV in mud crab, as well as detail information for identifying novel genes in the absence of the mud crab genome database. Copyright © 2016. Published by Elsevier Ltd.
Rai, Suchita; Wasewar, Kailas L; Lataye, Dilip H; Mishra, Rajshekhar S; Puttewar, Suresh P; Chaddha, Mukesh J; Mahindiran, P; Mukhopadhyay, Jyoti
2012-09-01
'Red mud' or 'bauxite residue', a waste generated from alumina refinery is highly alkaline in nature with a pH of 10.5-12.5. Red mud poses serious environmental problems such as alkali seepage in ground water and alkaline dust generation. One of the options to make red mud less hazardous and environmentally benign is its neutralization with acid or an acidic waste. Hence, in the present study, neutralization of alkaline red mud was carried out using a highly acidic waste (pickling waste liquor). Pickling waste liquor is a mixture of strong acids used for descaling or cleaning the surfaces in steel making industry. The aim of the study was to look into the feasibility of neutralization process of the two wastes using Taguchi's design of experimental methodology. This would make both the wastes less hazardous and safe for disposal. The effect of slurry solids, volume of pickling liquor, stirring time and temperature on the neutralization process were investigated. The analysis of variance (ANOVA) shows that the volume of the pickling liquor is the most significant parameter followed by quantity of red mud with 69.18% and 18.48% contribution each respectively. Under the optimized parameters, pH value of 7 can be achieved by mixing the two wastes. About 25-30% of the total soda from the red mud is being neutralized and alkalinity is getting reduced by 80-85%. Mineralogy and morphology of the neutralized red mud have also been studied. The data presented will be useful in view of environmental concern of red mud disposal.
Effect of formulation variables on the physical properties and stability of Dead Sea mud masks.
Shahin, Sawsan; Hamed, Saja; Alkhatib, Hatim S
2015-01-01
The physical stability of Dead Sea mud mask formulations under different conditions and their rheological properties were evaluated as a function of the type and level of thickeners, level of the humectant, incorporation of ethanol, and mode of mud treatment. Formulations were evaluated in terms of visual appearance, pH, moisture content, spreadability, extrudability, separation, rate of drying at 32 degrees C, and rheological properties. Prepared mud formulations and over-the-shelf products showed viscoplastic shear thinning behavior; satisfactory rheological behavior was observed with formulations containing a total concentration of thickeners less than 10% (w/w). Casson and Herschel-Bulkley models were found the most suitable to describe the rheological data of the prepared formulations. Thickener incorporation decreased phase separation and improved formulation stability. Bentonite incorporation in the mud prevented color changes during stability studies while glycerin improved spreadability. Addition of 5% (w/w) ethanol improved mud extrudability, slightly increased percent separation, accelerated drying at 32 degrees C, and decreased viscosity and yield stress values. Different mud treatment techniques did not cause a clear behavioral change in the final mud preparation. B10G and K5B5G were labeled as "best formulas" based on having satisfactory physical and aesthetic criteria investigated in this study, while other formulations failed in one or more of the tests we have performed.
Anatomy Of The ‘LuSi’ Mud Eruption, East Java
NASA Astrophysics Data System (ADS)
Tingay, M. R.
2009-12-01
Early in the morning of the 29th of May 2006, hot mud started erupting from the ground in the densely populated Porong District of Sidoarjo, East Java. With initial flow rates of ~5000 cubic meters per day, the mud quickly inundated neighbouring villages. Over two years later and the ‘Lusi’ eruption has increased in strength, expelling over 90 million cubic meters of mud at an average rate of approximately 100000 cubic meters per day. The mud flow has now covered over 700 hectares of land to depths of over 25 meters, engulfing a dozen villages and displacing approximately 40000 people. In addition to the inundated areas, other areas are also at risk from subsidence and distant eruptions of gas. However, efforts to stem the mud flow or monitor its evolution are hampered by our overall lack of knowledge and consensus on the subsurface anatomy of the Lusi mud volcanic system. In particular, the largest and most significant uncertainties are the source of the erupted water (shales versus deep carbonates), the fluid flow pathways (purely fractures versus mixed fracture and wellbore) and disputes over the subsurface geology (nature of deep carbonates, lithology of rocks between shale and carbonates). This study will present and overview of the anatomy of the Lusi mud volcanic system with particular emphasis on these critical uncertainties and their influence on the likely evolution of disaster.
Observations of sediment transport on the Amazon subaqueous delta
Sternberg, R.W.; Cacchione, D.A.; Paulson, B.; Kineke, G.C.; Drake, D.E.
1996-01-01
A 19-day time series of fluid, flow, and suspended-sediment characteristics in the benthic boundary layer is analyzed to identify major sedimentary processes active over the prodelta region of the Amazon subaqueous delta. Measurements were made by the benthic tripod GEOPROBE placed on the seabed in 65 m depth near the base of the deltaic foreset beds from 11 February to 3 March 1990, during the time of rising water and maximum sediment discharge of the Amazon River; and the observations included: hourly measurements of velocity and suspended-sediment concentration at four levels above the seabed; waves and tides; and seabed elevation. Results of the first 14-day period of the time series record indicate that sediment resuspension occurred as a result of tidal currents (91% of the time) and surface gravity waves (46% of the time). Observations of suspended sediment indicated that particle flux in this region is 0.4-2% of the flux measured on the adjacent topset deposits and is directed to the north and landward relative to the Brazilian coast (268??T). Fortnightly variability is strong, with particle fluxes during spring tides five times greater than during neap tides. On the 15th day of the data record, a rapid sedimentation event was documented in which 44 cm of sediment was deposited at the study site over a 14-h period. Evaluation of various mechanisms of mass sediment movement suggests that this event represents downslope migration of fluid muds from the upper foreset beds that were set in motion by boundary shear stresses generated by waves and currents. This transport mechanism appears to occur episodically and may represent a major source of sediment to the lower foreset-bottomset region of the subaqueous delta.
Martínez, Carmen; Gayoso, Jorge; Canals, Carmen; Finel, Hervé; Peggs, Karl; Dominietto, Alida; Castagna, Luca; Afanasyev, Boris; Robinson, Stephen; Blaise, Didier; Corradini, Paolo; Itälä-Remes, Maija; Bermúdez, Arancha; Forcade, Edouard; Russo, Domenico; Potter, Michael; McQuaker, Grant; Yakoub-Agha, Ibrahim; Scheid, Christof; Bloor, Adrian; Montoto, Silvia; Dreger, Peter; Sureda, Anna
2017-10-20
Purpose To compare the outcome of patients with Hodgkin lymphoma who received post-transplantation cyclophosphamide-based haploidentical (HAPLO) allogeneic hematopoietic cell transplantation with the outcome of patients who received conventional HLA-matched sibling donor (SIB) and HLA-matched unrelated donor (MUD). Patients and Methods We retrospectively evaluated 709 adult patients with Hodgkin lymphoma who were registered in the European Society for Blood and Marrow Transplantation database who received HAPLO (n = 98), SIB (n = 338), or MUD (n = 273) transplantation. Results Median follow-up of survivors was 29 months. No differences were observed between groups in the incidence of acute graft-versus-host disease (GVHD). HAPLO was associated with a lower risk of chronic GVHD (26%) compared with MUD (41%; P = .04). Cumulative incidence of nonrelapse mortality at 1 year was 17%, 13%, and 21% in HAPLO, SIB, and MUD, respectively, and corresponding 2-year cumulative incidence of relapse or progression was 39%, 49%, and 32%, respectively. On multivariable analysis, relative to SIB, nonrelapse mortality was similar in HAPLO ( P = .26) and higher in MUD ( P = .003), and risk of relapse was lower in both HAPLO ( P = .047) and MUD ( P < .001). Two-year overall survival and progression-free survival were 67% and 43% for HAPLO, 71% and 38% for SIB, and 62% and 45% for MUD, respectively. There were no significant differences in overall survival or progression-free survival between HAPLO and SIB or MUD. The rate of the composite end point of extensive chronic GVHD and relapse-free survival was significantly better for HAPLO (40%) compared with SIB (28%; P = .049) and similar to MUD (38%; P = .59). Conclusion Post-transplantation cyclophosphamide-based HAPLO transplantation results in similar survival outcomes compared with SIB and MUD, which confirms its suitability when no conventional donor is available. Our results also suggest that HAPLO results in a lower risk of chronic GVHD than MUD transplantation.
NASA Astrophysics Data System (ADS)
Hogg, Charlie A. R.; Dalziel, Stuart B.; Huppert, Herbert E.; Imberger, Jörg
2015-09-01
In many important natural and industrial systems, gravity currents of dense fluid feed basins. Examples include lakes fed by dense rivers and auditoria supplied with cooled air by ventilation systems. As we will show, the entrainment into such buoyancy driven currents can be influenced by viscous forces. Little work, however, has examined this viscous influence and how entrainment varies with the Reynolds number, Re. Using the idea of an entrainment coefficient, E, we derive a mathematical expression for the rise of the front at the top of the dense fluid ponding in a basin, where the horizontal cross-sectional area of the basin varies linearly with depth. We compare this expression to experiments on gravity currents with source Reynolds numbers, Res, covering the broad range 100 < Res < 1500. The form of the observed frontal rises was well approximated by our theory. By fitting the observed frontal rises to the theoretical form with E as the free parameter, we find a linear trend for E(Res) over the range 350 < Res < 1100, which is in the transition to turbulent flow. In the experiments, the entrainment coefficient, E, varied from 4 × 10-5 to 7 × 10-2. These observations show that viscous damping can be a dominant influence on gravity current entrainment in the laboratory and in geophysical flows in this transitional regime.
NASA Astrophysics Data System (ADS)
Wan, Z.; Xu, X.; Wang, X.
2016-12-01
The mud diapir/volcano is an important indicator for gas hydrate exploration, which develops widely in continental slopes. There are many mud diapirs/volcanoes developed in northern South China Sea continental slope. Guangzhou Marine Geological Survey (GMGS) of the Chinese Ministry of Land and Resources targeted mud diapirs/volcanoes and deployed gas hydrate drilling in the Shenhu area. An obvious mud diapir developed below borehole number SH5, and bottom-simulating reflection (BSR) was also detected, but no gas hydrates were found at this borehole. We analyzed the thermal structure of mud diapirs and their relationship to the occurrence of gas hydrates. The in situ temperature at the seafloor is approximately 2.2 2.5oC in the study area. Seafloor heat flow values of SH5 is 71.4mW/m2. Temperature increases rapidly to 17oC from 40 m to 100 m and stays in the range of 17 to 19oC below 100 m. And the thermal conductivity value of SH5 is approximately 1.0 W/m·k from top to bottom. The evolution of the mud diapir/volcanoes can be divided into three stages within a continuous geological process controlling the gas hydrate reservoir. During the late stage, liquid from the mud diapir/volcanoes begins to invade the gas hydrate stability zone . Because of the high unit heat capacity of liquid, the whole temperature field of the surrounding layers increases significantly when the mud diapir/volcanoes pierces upwards. This high heat flow leads to decomposition of the gas hydrates. Therefore, the reason of SH5 did not find gas hydrates may be that the mud diapir had pierced through during the late stage, leading to gas hydrate decomposition, even though there is an obvious BSR. This work was supported by Science and Technology Program of Guangzhou (No. 201607010214) and National Nature Science Foundation of China (No. 91128203,41102077).
Thermal mud maturation: organic matter and biological activity.
Centini, M; Tredici, M R; Biondi, N; Buonocore, A; Maffei Facino, R; Anselmi, C
2015-06-01
Many of the therapeutic and cosmetic treatments offered in spas are centred on mud therapy, to moisturize the skin and prevent skin ageing and rheumatic diseases. Thermal mud is a complex matrix composed of organic and inorganic elements which contribute to its functions. It is a natural product derived from the long mixing of clay and thermal water. During its maturation, organic substances are provided by the microalgae, which develop characteristic of the composition of thermal water. The aim of this study was to identify methods for introducing objective parameters as a basis for characterizing thermal mud and assessing its efficacy. Samples of thermal mud were collected at the Saturnia spa, where there are several sulphureous pools. The maturation of the mud was evaluated by organic component determination using extractive methods and chromatographic analysis (HPLC, GC-MS, SPME). We also studied the radical scavenging activity of mud samples at different stages of maturation, in a homogeneous phase, using several tests (DPPH, ORAC, ABTS). We identified several classes of compounds: saturated and unsaturated fatty acids, hydroxyl acids, dicarboxylic acids, ketoacids, alcohols and others. SPME analysis showed the presence of various hydrocarbons compounds (C(11) -C(17)) and long-chain alcohols (C(12) -C(16)). Six or seven months seemed appropriate to complete the process of maturation, and the main effect of maturation time was the increase of lipids. Six-month mud showed the highest activity. The hydrophilic extract was more active than the lipophilic extract. The results indicate that maturation of thermal mud can be followed on the basis of the changes in its organic composition and antioxidant properties along the time. They also highlight the need to develop reference standards for thermal muds in relation to assess their use for therapeutic and cosmetic purposes. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
NASA Astrophysics Data System (ADS)
Ning, Fulong; Zhang, Keni; Wu, Nengyou; Zhang, Ling; Li, Gang; Jiang, Guosheng; Yu, Yibing; Liu, Li; Qin, Yinghong
2013-06-01
To our knowledge, this study is the first to perform a numerical simulation and analysis of the dynamic behaviour of drilling mud invasion into oceanic gas-hydrate-bearing sediment (GHBS) and to consider the effects of such an invasion on borehole stability and the reliability of well logging. As a case study, the simulation background sets up the conditions of mud temperature over hydrate equilibrium temperature and overbalanced drilling, considering the first Chinese expedition to drill gas hydrate (GMGS-1). The results show that dissociating gas may form secondary hydrates in the sediment around borehole by the combined effects of increased pore pressure (caused by mud invasion and flow resistance), endothermic cooling that accompanies hydrate dissociation compounded by the Joule-Thompson effect and the lagged effect of heat transfer in sediments. The secondary hydrate ring around the borehole may be more highly saturated than the in situ sediment. Mud invasion in GHBS is a dynamic process of thermal, fluid (mud invasion), chemical (hydrate dissociation and reformation) and mechanical couplings. All of these factors interact and influence the pore pressure, flow ability, saturation of fluid and hydrates, mechanical parameters and electrical properties of sediments around the borehole, thereby having a strong effect on borehole stability and the results of well logging. The effect is particularly clear in the borehole SH7 of GMGS-1 project. The borehole collapse and resistivity distortion were observed during practical drilling and wireline logging operations in borehole SH7 of the GMGS-1.mud density (i.e. the corresponding borehole pressure), temperature and salinity have a marked influence on the dynamics of mud invasion and on hydrate stability. Therefore, perhaps well-logging distortion caused by mud invasion, hydrate dissociation and reformation should be considered for identifying and evaluating gas hydrate reservoirs. And some suitable drilling measurements need to be adopted to reduce the risk of well-logging distortion and borehole instability.
NASA Astrophysics Data System (ADS)
Tseng, Y.; Lin, S.; Hsieh, I. C.; Lien, K. L.
2016-12-01
Tsanyao mud volcano is a 400 meters high, 5 kilometers in diameter, a center crater of 50 meters width activing venting mud diapir. The gigantic size of mud volcano indicate massive transportation of material, i.e., gas, fluid, and breccia from deep to the sea floor in building up the mud volcano. The mud volcano is located at the upper slope of the accretionary wedge with a surrounding water depth of about xx m, offshore Southwestern Taiwan. On shore, a series of active mud volcanos also exist in a trend similar to those found offshore. In order to understand sources of gas, fluid, solid materials and the effect of gas migration and associate authigenic mineral formation, we have obtained multibeam bathymetry, water column echo sounding, together with sediment XRD and SEM and pore water composition of methane, sulfide, sulfate, chloride, potassium, lithium, boron, and water O-18 at the study mud volcano. We have observed more than 30 flares around the main cone within a perimeter of 10 square miles. δ13C values of methane in the pore water ranged from -30 to -50 ‰. The lower C13 ratios, together with high C2+/C1 ratios demonstrated that vent gas is mostly thermogenic in origin. Higher thermal gradient and water temperature indicated that cone top is unfavorable for gas-hydrate formation, however, gas hydrate may exist at a deeper part of the mud volcano system. High concentration of sulfide presence right near the sulfate-methane interface, a result of anoxic methane oxidation. However, low concentrations of pyrite in sediments indicated that AOM did not favor pyrite formation at depth. In addition, abundant siderite were found in the sediments collected in the mud volcano cone. Rapid consumption of sulfate through AOM reaction generated a condition favor the siderite fomation, instead of the typical pyrite formation commonly observed.
NASA Astrophysics Data System (ADS)
Tuckness, D. G.; Jost, B.
1995-08-01
Current knowledge of the lunar gravity field is presented. The various methods used in determining these gravity fields are investigated and analyzed. It will be shown that weaknesses exist in the current models of the lunar gravity field. The dominant part of this weakness is caused by the lack of lunar tracking data information (farside, polar areas), which makes modeling the total lunar potential difficult. Comparisons of the various lunar models reveal an agreement in the low-order coefficients of the Legendre polynomials expansions. However, substantial differences in the models can exist in the higher-order harmonics. The main purpose of this study is to assess today's lunar gravity field models for use in tomorrow's lunar mission designs and operations.
2015-09-30
We aim at understanding the impact of tidal , seasonal, and mesoscale variability of the internal wave field and how it influences the surface waves ...Interaction of Surface Gravity Waves with Nonlinear Internal Gravity Waves Lian Shen St. Anthony Falls Laboratory and Department of Mechanical...on studying surface gravity wave evolution and spectrum in the presence of surface currents caused by strongly nonlinear internal solitary waves
NASA Astrophysics Data System (ADS)
Yilbas, Bekir Sami.; Ali, Haider; Khaled, Mazen M.; Al-Aqeeli, Nasser; Abu-Dheir, Numan; Varanasi, Kripa K.
2015-10-01
Recent developments in climate change have increased the frequency of dust storms in the Middle East. Dust storms significantly influence the performances of solar energy harvesting systems, particularly (photovoltaic) PV systems. The characteristics of the dust and the mud formed from this dust are examined using various analytical tools, including optical, scanning electron, and atomic force microscopies, X-ray diffraction, energy spectroscopy, and Fourier transform infrared spectroscopy. The adhesion, cohesion and frictional forces present during the removal of dry mud from the glass surface are determined using a microtribometer. Alkali and alkaline earth metal compounds in the dust dissolve in water to form a chemically active solution at the glass surface. This solution modifies the texture of the glass surface, thereby increasing the microhardness and decreasing the transmittance of the incident optical radiation. The force required to remove the dry mud from the glass surface is high due to the cohesive forces that result from the dried mud solution at the interface between the mud and the glass. The ability altering the characteristics of the glass surface could address the dust/mud-related limitations of protective surfaces and has implications for efficiency enhancements in solar energy systems.
Fonslow, Bryan R.; Niessen, Sherry M.; Singh, Meha; Wong, Catherine C.; Xu, Tao; Carvalho, Paulo C.; Choi, Jeong; Park, Sung Kyu; Yates, John R.
2012-01-01
Herein we report the characterization and optimization of single-step inline enrichment of phosphopeptides directly from small amounts of whole cell and tissue lysates (100 – 500 μg) using a hydroxyapatite (HAP) microcolumn and Multidimensional Protein Identification Technology (MudPIT). In comparison to a triplicate HILIC-IMAC phosphopeptide enrichment study, ~80% of the phosphopeptides identified using HAP-MudPIT were unique. Similarly, analysis of the consensus phosphorylation motifs between the two enrichment methods illustrates the complementarity of calcium-and iron-based enrichment methods and the higher sensitivity and selectivity of HAP-MudPIT for acidic motifs. We demonstrate how the identification of more multiply phosphorylated peptides from HAP-MudPIT can be used to quantify phosphorylation cooperativity. Through optimization of HAP-MudPIT on a whole cell lysate we routinely achieved identification and quantification of ca. 1000 phosphopeptides from a ~1 hr enrichment and 12 hr MudPIT analysis on small quantities of material. Finally, we applied this optimized method to identify phosphorylation sites from a mass-limited mouse brain region, the amygdala (200 – 500 μg), identifying up to 4000 phosphopeptides per run. PMID:22509746
Yilbas, Bekir Sami; Ali, Haider; Khaled, Mazen M; Al-Aqeeli, Nasser; Abu-Dheir, Numan; Varanasi, Kripa K
2015-10-30
Recent developments in climate change have increased the frequency of dust storms in the Middle East. Dust storms significantly influence the performances of solar energy harvesting systems, particularly (photovoltaic) PV systems. The characteristics of the dust and the mud formed from this dust are examined using various analytical tools, including optical, scanning electron, and atomic force microscopies, X-ray diffraction, energy spectroscopy, and Fourier transform infrared spectroscopy. The adhesion, cohesion and frictional forces present during the removal of dry mud from the glass surface are determined using a microtribometer. Alkali and alkaline earth metal compounds in the dust dissolve in water to form a chemically active solution at the glass surface. This solution modifies the texture of the glass surface, thereby increasing the microhardness and decreasing the transmittance of the incident optical radiation. The force required to remove the dry mud from the glass surface is high due to the cohesive forces that result from the dried mud solution at the interface between the mud and the glass. The ability altering the characteristics of the glass surface could address the dust/mud-related limitations of protective surfaces and has implications for efficiency enhancements in solar energy systems.
Martian mud volcanism: Terrestrial analogs and implications for formational scenarios
Skinner, J.A.; Mazzini, A.
2009-01-01
The geology of Mars and the stratigraphic characteristics of its uppermost crust (mega-regolith) suggest that some of the pervasively-occurring pitted cones, mounds, and flows may have formed through processes akin to terrestrial mud volcanism. A comparison of terrestrial mud volcanism suggests that equivalent Martian processes likely required discrete sedimentary depocenters, volatile-enriched strata, buried rheological instabilities, and a mechanism of destabilization to initiate subsurface flow. We outline five formational scenarios whereby Martian mud volcanism might have occurred: (A) rapid deposition of sediments, (B) volcano-induced destabilization, (C) tectonic shortening, (D) long-term, load-induced subsidence, and (E) seismic shaking. We describe locations within and around the Martian northern plains that broadly fit the geological context of these scenarios and which contain mud volcano-like landforms. We compare terrestrial and Martian satellite images and examine the geological settings of mud volcano provinces on Earth in order to describe potential target areas for piercement structures on Mars. Our comparisons help to evaluate not only the role of water as a functional component of geological processes on Mars but also how Martian mud volcanoes could provide samples of otherwise inaccessible strata, some of which could contain astrobiological evidence.
New mud system produces solids-free, reusable water
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-02-01
The Corpus Christi, Texas, based Cameron Equipment Co., Inc., has developed a closed-loop mud treating system that removes solids from water-based systems and leaves the separated fluid clean and chemical free enough to be re-used directly on the rig. The system has been successfully applied by a Gulf of Mexico operator in areas where zero discharge is required. The alternative mud conditions program offered by the developers is called the Cameron Fluid Recycling System. Designed for closed-loop water-based fluids, the system is a new method of removing solids from normally discharged fluids such as drilling mud, waste and wash water,more » or any other water-based fluid that contains undesirable solids. The patented method efficiently produces end products that are (1) dry solids; and (2) essentially 100% solids-free fluid that can be re-used in the same mud system. All excess drilling mud, and all wash water that would normally go to the reserve pit or a cuttings barge are collected in a tank. Recycled fluid is compatible with the mud system fluid, no harmful chemicals are used, and pH is not altered.« less
Comparative study of the thermal properties of mud and peat solutions applied in clinical practice.
Beer, A M; Grozeva, A; Sagorchev, P; Lukanov, J
2003-11-01
Different peloids as e.g. mud and peat have been traditionally used for therapeutic purposes successfully, especially of there thermal actions. It was the aim of the experimental study to compare the thermal properties of two peloids, mud and peat, with a view to assessing their thermal effects when they are applied in clinical practice. The studies were carried out using peat of the marsh type of peats (Hochmoor), and curative Pomorie (Bulgaria) mud. As important parameters were determined the specific thermal capacity at constant pressure (Cp), the density of solutions (rho), the cooling rate (m), the coefficient of temperature transfer (a) of solutions and the coefficient of thermal conductivity (lambda) of solutions of peat and curative mud, compared to water bath. The comparative studies of the thermal properties of water and water solutions of peat and curative mud show that the thermal effect of the water bath is substantially smaller than that of the peat and mud applications. This difference is due to a greater extent to the high values of the dynamic viscosity, not allowing cooling by convection and protecting the surface of the skin upon applications of peloid solutions with a higher temperature.
Bushart, Thomas J; Cannon, Ashley E; Ul Haque, Aeraj; San Miguel, Phillip; Mostajeran, Kathy; Clark, Gregory B; Porterfield, D Marshall; Roux, Stanley J
2013-01-01
Gravity regulates the magnitude and direction of a trans-cell calcium current in germinating spores of Ceratopteris richardii. Blocking this current with nifedipine blocks the spore's downward polarity alignment, a polarization that is fixed by gravity ∼10 h after light induces the spores to germinate. RNA-seq analysis at 10 h was used to identify genes potentially important for the gravity response. The data set will be valuable for other developmental and phylogenetic studies. De novo Newbler assembly of 958 527 reads from Roche 454 sequencing was executed. The sequences were identified and analyzed using in silico methods. The roles of endomembrane Ca(2+)-ATPase pumps and apyrases in the gravity response were further tested using pharmacological agents. Transcripts related to calcium signaling and ethylene biosynthesis were identified as notable constituents of the transcriptome. Inhibiting the activity of endomembrane Ca(2+)-ATPase pumps with 2,5-di-(t-butyl)-1,4-hydroquinone diminished the trans-cell current, but increased the orientation of the polar axis to gravity. The effects of applied nucleotides and purinoceptor antagonists gave novel evidence implicating extracellular nucleotides as regulators of the gravity response in these fern spores. In addition to revealing general features of the transcriptome of germinating spores, the results highlight a number of calcium-responsive and light-receptive transcripts. Pharmacologic assays indicate endomembrane Ca(2+)-ATPases and extracellular nucleotides may play regulatory roles in the gravity response of Ceratopteris spores.
Mud Volcanoes - Analogs to Martian Cones and Domes (by the Thousands!)
NASA Technical Reports Server (NTRS)
Allen, Carlton C.; Oehler, Dorothy
2010-01-01
Mud volcanoes are mounds formed by low temperature slurries of gas, liquid, sediments and rock that erupt to the surface from depths of meters to kilometers. They are common on Earth, with estimates of thousands onshore and tens of thousands offshore. Mud volcanoes occur in basins with rapidly-deposited accumulations of fine-grained sediments. Such settings are ideal for concentration and preservation of organic materials, and mud volcanoes typically occur in sedimentary basins that are rich in organic biosignatures. Domes and cones, cited as possible mud volcanoes by previous authors, are common on the northern plains of Mars. Our analysis of selected regions in southern Acidalia Planitia has revealed over 18,000 such features, and we estimate that more than 40,000 occur across the area. These domes and cones strongly resemble terrestrial mud volcanoes in size, shape, morphology, associated flow structures and geologic setting. Geologic and mineralogic arguments rule out alternative formation mechanisms involving lava, ice and impacts. We are studying terrestrial mud volcanoes from onshore and submarine locations. The largest concentration of onshore features is in Azerbaijan, near the western edge of the Caspian Sea. These features are typically hundreds of meters to several kilometers in diameter, and tens to hundreds of meters in height. Satellite images show spatial densities of 20 to 40 eruptive centers per 1000 square km. Many of the features remain active, and fresh mud flows as long as several kilometers are common. A large field of submarine mud volcanoes is located in the Gulf of Cadiz, off the Atlantic coasts of Morocco and Spain. High-resolution sonar bathymetry reveals numerous km-scale mud volcanoes, hundreds of meters in height. Seismic profiles demonstrate that the mud erupts from depths of several hundred meters. These submarine mud volcanoes are the closest morphologic analogs yet found to the features in Acidalia Planitia. We are also conducting laboratory analyses of surface samples collected from mud volcanoes in Azerbaijan, Taiwan and Japan. X-ray diffraction, visible / near infrared reflectance spectroscopy and Raman spectroscopy show that the samples are dominated by mixed-layer smectite clays, along with quartz, calcite and pyrite. Thin section analysis by optical and scanning electron microscopy confirms the mineral identifications. These samples also contain chemical and morphological biosignatures, including common microfossils, with evidence of partial replacement by pyrite. The bulk samples contain approximately 1 wt% total organic carbon and 0.4 mg / gm volatile hydrocarbons. The thousands of features in Acidalia Planitia cited as analogous to terrestrial mud volcanoes clearly represent an important element in the sedimentary record of Mars. Their location, in the distal depocenter for massive Hesperian-age floods, suggests that they contain fine-grained sediments from a large catchment area in the martian highlands. We have proposed these features as a new class of exploration target that can provide access to minimally-altered material from significant depth. By analogy to terrestrial mud volcanoes, these features may also be excellent sites for the sampling martian organics and subsurface microbial life, if such exist or ever existed.
Rassulova, M A; Siziakova, L A; Aĭrapetova, N S
2009-01-01
The influence of application of naftalan and therapeutic muds on clinical and roentgenological parameters, external respiration function, biochemical and immunological characteristics of the inflammatory process was studied in 82 patients presenting with protracted pneumonia and compared with the outcome of therapy using no physical factors. The application of naftalan and therapeutic muds was shown to reduce activity of inflammatory processes, improve airway patency and the state ofbronchial mucosa. Naftalan produced better therapeutic effect than muds.
Particle Image Velocimetry Study of Density Current Fronts
ERIC Educational Resources Information Center
Martin, Juan Ezequiel
2009-01-01
Gravity currents are flows that occur when a horizontal density difference causes fluid to move under the action of gravity; density currents are a particular case, for which the scalar causing the density difference is conserved. Flows with a strong effect of the horizontal density difference, even if only partially driven by it--such as the…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alan Black; Arnis Judzis
2003-01-01
Progress during current reporting year 2002 by quarter--Progress during Q1 2002: (1) In accordance to Task 7.0 (D. No.2 Technical Publications) TerraTek, NETL, and the Industry Contributors successfully presented a paper detailing Phase 1 testing results at the February 2002 IADC/SPE Drilling Conference, a prestigious venue for presenting DOE and private sector drilling technology advances. The full reference is as follows: IADC/SPE 74540 ''World's First Benchmarking of Drilling Mud Hammer Performance at Depth Conditions'' authored by Gordon A. Tibbitts, TerraTek; Roy C. Long, US Department of Energy, Brian E. Miller, BP America, Inc.; Arnis Judzis, TerraTek; and Alan D. Black,more » TerraTek. Gordon Tibbitts, TerraTek, will presented the well-attended paper in February of 2002. The full text of the Mud Hammer paper was included in the last quarterly report. (2) The Phase 2 project planning meeting (Task 6) was held at ExxonMobil's Houston Greenspoint offices on February 22, 2002. In attendance were representatives from TerraTek, DOE, BP, ExxonMobil, PDVSA, Novatek, and SDS Digger Tools. (3) PDVSA has joined the advisory board to this DOE mud hammer project. PDVSA's commitment of cash and in-kind contributions were reported during the last quarter. (4) Strong Industry support remains for the DOE project. Both Andergauge and Smith Tools have expressed an interest in participating in the ''optimization'' phase of the program. The potential for increased testing with additional Industry cash support was discussed at the planning meeting in February 2002. Progress during Q2 2002: (1) Presentation material was provided to the DOE/NETL project manager (Dr. John Rogers) for the DOE exhibit at the 2002 Offshore Technology Conference. (2) Two meeting at Smith International and one at Andergauge in Houston were held to investigate their interest in joining the Mud Hammer Performance study. (3) SDS Digger Tools (Task 3 Benchmarking participant) apparently has not negotiated a commercial deal with Halliburton on the supply of fluid hammers to the oil and gas business. (4) TerraTek is awaiting progress by Novatek (a DOE contractor) on the redesign and development of their next hammer tool. Their delay will require an extension to TerraTek's contracted program. (5) Smith International has sufficient interest in the program to start engineering and chroming of collars for testing at TerraTek. (6) Shell's Brian Tarr has agreed to join the Industry Advisory Group for the DOE project. The addition of Brian Tarr is welcomed as he has numerous years of experience with the Novatek tool and was involved in the early tests in Europe while with Mobil Oil. (7) Conoco's field trial of the Smith fluid hammer for an application in Vietnam was organized and has contributed to the increased interest in their tool. Progress during Q3 2002: (1) Smith International agreed to participate in the DOE Mud Hammer program. (2) Smith International chromed collars for upcoming benchmark tests at TerraTek, now scheduled for 4Q 2002. (3) ConocoPhillips had a field trial of the Smith fluid hammer offshore Vietnam. The hammer functioned properly, though the well encountered hole conditions and reaming problems. ConocoPhillips plan another field trial as a result. (4) DOE/NETL extended the contract for the fluid hammer program to allow Novatek to ''optimize'' their much delayed tool to 2003 and to allow Smith International to add ''benchmarking'' tests in light of SDS Digger Tools' current financial inability to participate. (5) ConocoPhillips joined the Industry Advisors for the mud hammer program. Progress during Q4 2002: (1) Smith International participated in the DOE Mud Hammer program through full scale benchmarking testing during the week of 4 November 2003. (2) TerraTek acknowledges Smith International, BP America, PDVSA, and ConocoPhillips for cost-sharing the Smith benchmarking tests allowing extension of the contract to add to the benchmarking testing program. (3) Following the benchmark testing of the Smith International hammer, representatives from DOE/NETL, TerraTek, Smith International and PDVSA met at TerraTek in Salt Lake City to review observations, performance and views on the optimization step for 2003. (4) The December 2002 issue of Journal of Petroleum Technology (Society of Petroleum Engineers) highlighted the DOE fluid hammer testing program and reviewed last years paper on the benchmark performance of the SDS Digger and Novatek hammers. (5) TerraTek's Sid Green presented a technical review for DOE/NETL personnel in Morgantown on ''Impact Rock Breakage'' and its importance on improving fluid hammer performance. Much discussion has taken place on the issues surrounding mud hammer performance at depth conditions.« less
Study of the marine environment of the northern Gulf of California
NASA Technical Reports Server (NTRS)
Hendrickson, J. R. (Principal Investigator)
1972-01-01
The author has identified the following significant results. Preliminary analysis of the first three months of ERTS-1 imagery have revealed that the MSS images have particular utility for study of turbidity patterns, current phenomena, and bathymetry throughout the test area. Early indications are that well defined spatial distributions of turbidity exist in the northern Gulf of California, and that for any one point in time, these distributions vary with depth. From a single set of images, as many as 3 turbidity maps may be generated, each indicating a vertical spatial relationship of the turbidity masses. The spatial distribution of turbidity masses depend partially upon the coincident currents. In the band of deepest penetration, a map can be gathered which roughly corresponds to the bathymetry of the area. The extreme tides in the northern Gulf of California result in vast areas which can be classified as intertidal mud flats. Information on the amount of exposure at the varying tidal states is important in analysis of these mud flat areas as nursery ground for Mexican commercial fisheries.
Occupational exposure to airborne contaminants during offshore oil drilling.
Kirkhus, Niels E; Thomassen, Yngvar; Ulvestad, Bente; Woldbæk, Torill; Ellingsen, Dag G
2015-07-01
The aim was to study exposure to airborne contaminants in oil drillers during ordinary work. Personal samples were collected among 65 drill floor workers on four stationary and six moveable rigs in the Norwegian offshore sector. Air concentrations of drilling mud were determined based on measurements of the non-volatile mud components Ca and Fe. The median air concentration of mud was 140 μg m(-3). Median air concentrations of oil mist (180 μg m(-3)), oil vapour (14 mg m(-3)) and organic carbon (46 μg m(-3)) were also measured. All contaminants were detected in all work areas (drill floor, shaker area, mud pits, pump room, other areas). The highest air concentrations were measured in the shaker area, but the differences in air concentrations between working areas were moderate. Oil mist and oil vapour concentrations were statistically higher on moveable rigs than on stationary rigs, but after adjusting for differences in mud temperature the differences between rig types were no longer of statistical significance. Statistically significant positive associations were found between mud temperature and the concentrations of oil mist (Spearman's R = 0.46) and oil vapour (0.39), and between viscosity of base oil and oil mist concentrations. Use of pressure washers was associated with higher air concentrations of mud. A series of 18 parallel stationary samples showed a high and statistically significant association between concentrations of organic carbon and oil mist (r = 0.98). This study shows that workers are exposed to airborne non-volatilized mud components. Air concentrations of volatile mud components like oil mist and oil vapour were low, but were present in all the studied working areas.
Triggering and dynamic evolution of the LUSI mud volcano, Indonesia
NASA Astrophysics Data System (ADS)
Mazzini, A.; Svensen, H.; Akhmanov, G. G.; Aloisi, G.; Planke, S.; Malthe-Sørenssen, A.; Istadi, B.
2007-09-01
Mud volcanoes are geologically important manifestations of vertical fluid flow and mud eruption in sedimentary basins worldwide. Their formation is predominantly ascribed to release of overpressure from clay- and organic-rich sediments, leading to impressive build-up of mud mountains in submarine and subaerial settings. Here we report on a newly born mud volcano appearing close to an active magmatic complex in a backarc sedimentary basin in Indonesia. The location of the mud volcano close to magmatic volcanoes results in a high background temperature gradient that triggers mineralogical transformations and geochemical reactions at shallow depth. The eruption of 100 °C mud and gas that started the 29th of May 2006 flooded a large area within the Sidoarjo village in Northeast Java. Thousands of people have so far been evacuated due to the mud flood hazards from the eruption. Since the initial eruption, the flow rate escalated from 5000 to 120,000 m 3/d during the first eleven weeks. Then the erupted volume started to pulsate between almost zero and 120,000 m 3/d in the period August 14 to September 10, whereas it increased dramatically following swarms of earthquakes in September, before reaching almost 180,000 m 3/d in December 2006. Sampling and observations were completed during two fieldwork campaigns on the site. The eruption of boiling water is accompanied by mud, aqueous vapour, CO 2 and CH 4. Based on geochemical and field results, we propose a mechanism where the eruptions started following the 27th of May earthquake due to fracturing and accompanied depressurization of > 100 °C pore fluids from > 1700 m depth. This resulted in the formation of a quasi-hydrothermal system with a geyser-like surface expression and with an activity influenced by the regional seismicity.
Zhou, Y-F; Haynes, R J; Naidu, R
2012-05-01
This study aims to examine whether addition of immobilising agents to a sandy, alkaline (pH = 8.1) soil, which had been contaminated with Pb and Zn by airborne particles from a Pb/Zn smelter, would substantially reduce metal bioavailability. The effectiveness of five waste materials (blast furnace (BF) slag, alum water treatment (WT) sludge, red mud, sugar mill mud and green waste compost) as metal immobilising agents was evaluated by incubating them with a contaminated soil for a period of 12 months at rates of 5% and 10% (w/w), after which, Rhodes grass was grown in the soils in a greenhouse study. Additions of WT sludge, BF slag and red mud reduced CaCl(2), CH(3)COOH, HCl and EDTA-extractable Zn but compost and mill mud had no appreciable immobilising effects. Additions of all amendments reduced levels of CaCl(2), CH(3)COOH and HCl-extractable Pb although concentrations of EDTA-extractable Pb remained unchanged. A sequential extraction procedure showed that additions of mill mud and compost increased the percentage of total Pb and Zn present in the oxidisable fraction whilst additions of the other materials increased the percentage present in the residual fraction. Rhodes grass yields were promoted greatly by additions of red mud, compost and particularly mill mud, and yields were negatively correlated with tissue Pb concentrations and extractable Pb. Red mud was the most effective material for lowering extractable Pb and Zn levels simultaneously while mill mud and compost were notably effective for Pb. A field evaluation in the study area is justified.
Corinaldesi, Cinzia; Dell'Anno, Antonio; Danovaro, Roberto
2012-06-01
Mud volcanoes are geological structures in the oceans that have key roles in the functioning of the global ecosystem. Information on the dynamics of benthic viruses and their interactions with prokaryotes in mud volcano ecosystems is still completely lacking. We investigated the impact of viral infection on the mortality and assemblage structure of benthic prokaryotes of five mud volcanoes in the Mediterranean Sea. Mud volcano sediments promote high rates of viral production (1.65-7.89 × 10(9) viruses g(-1) d(-1)), viral-induced prokaryotic mortality (VIPM) (33% cells killed per day) and heterotrophic prokaryotic production (3.0-8.3 μgC g(-1) d(-1)) when compared with sediments outside the mud volcano area. The viral shunt (that is, the microbial biomass converted into dissolved organic matter as a result of viral infection, and thus diverted away from higher trophic levels) provides 49 mgC m(-2) d(-1), thus fuelling the metabolism of uninfected prokaryotes and contributing to the total C budget. Bacteria are the dominant components of prokaryotic assemblages in surface sediments of mud volcanoes, whereas archaea dominate the subsurface sediment layers. Multivariate multiple regression analyses show that prokaryotic assemblage composition is not only dependant on the geochemical features and processes of mud volcano ecosystems but also on synergistic interactions between bottom-up (that is, trophic resources) and top-down (that is, VIPM) controlling factors. Overall, these findings highlight the significant role of the viral shunt in sustaining the metabolism of prokaryotes and shaping their assemblage structure in mud volcano sediments, and they provide new clues for our understanding of the functioning of cold-seep ecosystems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guliyev, I.A.; Aliyev, A.A.; Rahmanov, R.R.
Azerbaijan is a classic region for the study of mud volcanism. Of the 700 mud volcanoes known in the world, 220 are in Azerbaijan. These are of great interest, not least in relation to oil and gas exploration since they give information on subsurface sediments beyond the reach of drilling. Mud volcanoes are clearly visible on satellite images. They are confined to structural lineaments and associated fractures. Changes in the morphology of some mud volcanoes post-eruption can be detected from a series of images pre-dating and post-dating eruptions. Mud volcanoes are notable for gradients of temperature that are by anmore » order of magnitude or a factor of 102 greater than the temperature gradients established elsewhere. The gases of mud volcanoes consist mainly of methane (95-100%). There are small amounts of C{sub 2-6}, CO{sub 2}, N{sub 2}, He and Ar. The isotopic composition of carbon (ICC) within the methane varies from -61.29. to -35.W{close_quotes} which is isotopically heavier than the methane from producing fields. The ICC of the CO{sub 2} has a very wide range (from -49.6% to +23.1%), indicating several sources of its formation. The isotopically superheavy CO{sub 2} (+5%) is especially interesting. Oils from mud volcanoes are typically severely biodegraded. Their ICC ranges from -24.76% to -28.2%. A relationship between {partial_derivative}{sup l3}C of oils and ages of accumulations has been established. Waters of mud volcanoes are lightly mineralised, containing chiefly bicarbonates and sodium. The hydrogen composition of the water is abnormally heavy. Ejected rocks from mud volcanoes range in age from Cretaceous - Pliocene. Their study suggests that deeply buried reservoirs maintain good poroperm characteristics because of relatively little catagenesis.« less
Corinaldesi, Cinzia; Dell'Anno, Antonio; Danovaro, Roberto
2012-01-01
Mud volcanoes are geological structures in the oceans that have key roles in the functioning of the global ecosystem. Information on the dynamics of benthic viruses and their interactions with prokaryotes in mud volcano ecosystems is still completely lacking. We investigated the impact of viral infection on the mortality and assemblage structure of benthic prokaryotes of five mud volcanoes in the Mediterranean Sea. Mud volcano sediments promote high rates of viral production (1.65–7.89 × 109 viruses g−1 d−1), viral-induced prokaryotic mortality (VIPM) (33% cells killed per day) and heterotrophic prokaryotic production (3.0–8.3 μgC g−1 d−1) when compared with sediments outside the mud volcano area. The viral shunt (that is, the microbial biomass converted into dissolved organic matter as a result of viral infection, and thus diverted away from higher trophic levels) provides 49 mgC m−2 d−1, thus fuelling the metabolism of uninfected prokaryotes and contributing to the total C budget. Bacteria are the dominant components of prokaryotic assemblages in surface sediments of mud volcanoes, whereas archaea dominate the subsurface sediment layers. Multivariate multiple regression analyses show that prokaryotic assemblage composition is not only dependant on the geochemical features and processes of mud volcano ecosystems but also on synergistic interactions between bottom-up (that is, trophic resources) and top-down (that is, VIPM) controlling factors. Overall, these findings highlight the significant role of the viral shunt in sustaining the metabolism of prokaryotes and shaping their assemblage structure in mud volcano sediments, and they provide new clues for our understanding of the functioning of cold-seep ecosystems. PMID:22170423
NASA Astrophysics Data System (ADS)
Çelik Karakaya, Muazzez; Karakaya, Necati
2013-04-01
The study conducted on peloid used spas in İzmir city region (western part of Turkey) included the investigation of the mineralogical, physico-chemical and geochemical properties of the three types of peloid samples in order to assess the suitability of the material for healing- aesthetic-related purposes. In situ formed muds in lagoons near the Aegean Sea (named as first group) and inner swamp muds (second group) unprocessed and raw have been using therapy and thermal baths. Mud and hot springs at around the Aegean Sea have been popular since ancient times for the treatment of rheumatic diseases, musculoskeletal disorders in the region. The mineralogical characteristics of the thermal muds are in accordance with the geological origin of the material and water sources. Mineralogic composition, mineral content and morphologic properties of the samples were determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM-EDS). Chemical composition of the muds and thermal waters were determined by ICP-EAS and ICP-MS. Both of the sediment is fine- to medium size-grained and composed mostly of clay minerals, partially quartz, feldspar, carbonates, and halite, and rarely gypsum. The mineralogic composition of the muds controls the physico-chemical properties of the muds. Anion e.g., Cl, Br, and SO4, contents the thermal waters of the first group is extremely different and so the springs contain a high level of sodium chloride, magnesium sulphate, and calcium bicarbonate. The water temperature is 45 oC with a pH of 6.95 and electrical conductivity (EC) is 4.5 mS/lt in the first group while 71 oC with a pH 6.58 and EC is 2.52 mS/lt in the second ones. However, major and some of the trace element concentration of the mud samples are nearly similar, As, Cd, Cu, Hg, Ni, Sb, Se, T and Zn content of the first group is exceptionally lower than the second ones. And the hazardous element concentrations are extremely higher than the pharmaceutical clay in the second group peloids and also in thermal water, the element concentrations is not acceptable limits for peloids and waters. The element concentration is sourced from active fault system and low temperature precious metal deposits in the area which is widespread the thermal water circulated in. The anion contents of the water are related to sea water interaction. BET surface areas, plasticity, adsorbing, abrasiveness, hygroscopic water and cooling kinetics the characteristics both of the muds are nearly similar. However, cation exchange capacity and viscosity properties of the second group muds are better than the second, the physico-chemical properties both of the mud material are in acceptable level to some extent. Nevertheless, the appropriate characteristics of the second group muds when compared to some commercial used mud for medicinal and aesthetic purposes, if the hazardous element concentrations regulated.
Aluminium leaching from red mud by filamentous fungi.
Urík, Martin; Bujdoš, Marek; Milová-Žiaková, Barbora; Mikušová, Petra; Slovák, Marek; Matúš, Peter
2015-11-01
This contribution investigates the efficient and environmentally friendly aluminium leaching from red mud (bauxite residue) by 17 species of filamentous fungi. Bioleaching experiments were examined in batch cultures with the red mud in static, 7-day cultivation. The most efficient fungal strains in aluminium bioleaching were Penicillium crustosum G-140 and Aspergillus niger G-10. The A. niger G-10 strain was capable to extract up to approximately 141 mg·L(-1) of aluminium from 0.2 g dry weight red mud. Chemical leaching with organic acids mixture, prepared according to A. niger G-10 strain's respective fungal excretion during cultivation, proved that organic acids significantly contribute to aluminium solubilization from red mud. Copyright © 2015 Elsevier Inc. All rights reserved.
Gravity data from the Sierra Vista Subwatershed, Upper San Pedro Basin, Arizona
Kennedy, Jeffrey R.
2015-01-01
This report (1) summarizes changes to the Sierra Vista Subwatershed regional time-lapse gravity network with respect to station locations and (2) presents 2014 and 2015 gravity measurements and gravity values at each station. A prior gravity network, established between 2000 and 2005, was revised in 2014 to cover a larger number of stations over a smaller geographic area in order to decrease measurement and interpolation uncertainty. The network currently consists of 59 gravity stations, including 14 absolute-gravity stations. Following above-average rainfall during summer 2014, gravity increased at all but one of the absolute-gravity stations that were observed in both June 2014 and January 2015. This increase in gravity indicates increased groundwater storage in the aquifer and (or) unsaturated zone as a result of rainfall and infiltration.
Ye, Jie; Hu, Andong; Ren, Guoping; Zhou, Ting; Zhang, Guangming; Zhou, Shungui
2018-01-01
The role of red mud in the improvement of methanogenesis during sludge anaerobic digestion was innovatively investigated in this study. The results demonstrated that the addition of 20g/L red mud resulted in a 35.5% increase in methane accumulation. Red mud effectively promoted the hydrolysis-acidification of organic compounds in the sludge, which resulted in the increase of protein, polysaccharide, and VFAs by 5.1-94.5%. The activities of key enzymes were improved by 41.4-257.3%. Electrochemical measurements presented direct evidence that the electrical conductivity was significantly improved with red mud. More conductive magnetite was formed during the secondary mineralization after Fe(III) reduction by Fe (III)-reducing genes such as Clostridiaceae and Ruminococcaceae. The higher conductivity enhanced the electron transfer between the syntrophic bacteria (Geobacteraceae) and methanogens (Methanosaeta and Methanosarcina), and then improved the methanogenesis. This research provides a novel perspective on the synergism between sludge and red mud for methane production. Copyright © 2017 Elsevier Ltd. All rights reserved.
Yilbas, Bekir Sami; Ali, Haider; Al-Aqeeli, Naseer; Khaled, Mazen M; Said, Syed; Abu-Dheir, Numan; Merah, Necar; Youcef-Toumi, Kamal; Varanasi, Kripa K
2016-04-14
Owing to recent climate changes, dust storms are increasingly common, particularly in the Middle East region. Dust accumulation and subsequent mud formation on solid surfaces in humid environments typically have adverse effects on surface properties such as optical transmittance, surface texture, and microhardness. This is usually because the mud, which contains alkaline and ionic species, adheres strongly to the surface, often through chemical bonds, and is therefore difficult to remove. In this study, environmental dust and the after-effects of mud formed on a polycarbonate sheet, which is commonly used as a protective glass in photovoltaic cells. Ionic compounds (OH(-)) are shown to significantly affect the optical, mechanical, and textural characteristics of the polycarbonate surface, and to increase the adhesion work required to remove the dry mud from the polycarbonate surface upon drying. Such ability to modify characteristics of the polycarbonate surface could address the dust/mud-related limitations of superhydrophobic surfaces.
Yilbas, Bekir Sami.; Ali, Haider; Al-Aqeeli, Naseer; Khaled, Mazen M.; Said, Syed; Abu-Dheir, Numan; Merah, Necar; Youcef-Toumi, Kamal; Varanasi, Kripa K.
2016-01-01
Owing to recent climate changes, dust storms are increasingly common, particularly in the Middle East region. Dust accumulation and subsequent mud formation on solid surfaces in humid environments typically have adverse effects on surface properties such as optical transmittance, surface texture, and microhardness. This is usually because the mud, which contains alkaline and ionic species, adheres strongly to the surface, often through chemical bonds, and is therefore difficult to remove. In this study, environmental dust and the after-effects of mud formed on a polycarbonate sheet, which is commonly used as a protective glass in photovoltaic cells. Ionic compounds (OH−) are shown to significantly affect the optical, mechanical, and textural characteristics of the polycarbonate surface, and to increase the adhesion work required to remove the dry mud from the polycarbonate surface upon drying. Such ability to modify characteristics of the polycarbonate surface could address the dust/mud-related limitations of superhydrophobic surfaces. PMID:27076199
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lagunova, I.A.
A characteristic feature of the products of mud-volcano activity in the Kerch-Taman region is their high boron content. Distribution of boron in waters of mud volcanoes is characterized by restriction of anomalously high concentrations of boron to mud volcanoes actively operating at the present time in general, and to the most active period of operation of the individual volcano; there is a direct correlation between boron and the hydrocarbonate ion (r/sub B//HCO/sub 3// = 0.5), and between boron and carbon dioxide from the mud-volcano gases (r/sub B//CO/sub 2// = 0.4). The correlation is lacking between boron and mineralization, and betweenmore » boron and chlorine, the correlation is close to inverse. A spatial connection between areas of development of mud volcanism and belts of boron mineralization has been established. Anomalously high boron concentrations in the products of mud volcanism in the Kerch-Taman region are part of the overall increased boron capacity of the Crimea and the Caucasus, which has been controlled by recent magmatic activity.« less
Durability of Bricks Coated with Red mud Based Geopolymer Paste
NASA Astrophysics Data System (ADS)
Singh, Smita; Basavanagowda, S. N.; Aswath, M. U.; Ranganath, R. V.
2016-09-01
The present study is undertaken to assess the durability of concrete blocks coated with red mud - fly ash based geopolymer paste. Concrete blocks of size 200 x 200 x 100mm were coated with geopolymer paste synthesized by varying the percentages of red mud and fly ash. Uncoated concrete blocks were also tested for the durability for comparison. In thermal resistance test, the blocks were subjected to 600°C for an hour whereas in acid resistance test, they were kept in 5% sulphuric acid solution for 4 weeks. The specimens were thereafter studied for surface degradation, strength loss and weight loss. Pastes with red mud percentage greater than 50% developed lot of shrinkage cracks. The blocks coated with 30% and 50% red mud paste showed better durability than the other blocks. The use of blocks coated with red mud - fly ash geopolymer paste improves the aesthetics, eliminates the use of plaster and improves the durability of the structure.
Elastomers in mud motors for oil field applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hendrik, J.
1997-08-01
Mud motors, the most frequently used downhole drilling motors in modern drilling systems, are described in their application and function. The elastomeric liner in a mud motor acts as a huge continuous seal. Important properties of elastomers such as chemical resistance, fatigue resistance, mechanical strength, abrasion resistance, bonding to steel and processability are discussed. Advantages and disadvantages of NBR, HNBR, FKM, TFEP, and EPDM elastomers for mud motor applications are briefly described. The importance of drilling fluids and their physical and chemical impact on motor elastomers are described. Drilling fluids are categorized in: oil based-, synthetic-, and water based. Resultsmore » of compatibility tests in the different drilling muds of the presented categories demonstrate the complexity of elastomer development. Elastomers with an equally good performance in all drilling muds are not available. Future developments and improvements are directed towards higher chemical resistance at higher service temperatures. This will be possible only with improved elastomer-to-metal bonding, increased mechanical and better dynamic properties.« less
Superconducting gravity gradiometer and a test of inverse square law
NASA Technical Reports Server (NTRS)
Moody, M. V.; Paik, Ho Jung
1989-01-01
The equivalence principle prohibits the distinction of gravity from acceleration by a local measurement. However, by making a differential measurement of acceleration over a baseline, platform accelerations can be cancelled and gravity gradients detected. In an in-line superconducting gravity gradiometer, this differencing is accomplished with two spring-mass accelerometers in which the proof masses are confined to motion in a single degree of freedom and are coupled together by superconducting circuits. Platform motions appear as common mode accelerations and are cancelled by adjusting the ratio of two persistent currents in the sensing circuit. The sensing circuit is connected to a commercial SQUID amplifier to sense changes in the persistent currents generated by differential accelerations, i.e., gravity gradients. A three-axis gravity gradiometer is formed by mounting six accelerometers on the faces of a precision cube, with the accelerometers on opposite faces of the cube forming one of three in-line gradiometers. A dedicated satellite mission for mapping the earth's gravity field is an important one. Additional scientific goals are a test of the inverse square law to a part in 10(exp 10) at 100 km, and a test of the Lense-Thirring effect by detecting the relativistic gravity magnetic terms in the gravity gradient tensor for the earth.
Lockwood, Cindy L; Stewart, Douglas I; Mortimer, Robert J G; Mayes, William M; Jarvis, Adam P; Gruiz, Katalin; Burke, Ian T
2015-07-01
Red mud is a highly alkaline (pH >12) waste product from bauxite ore processing. The red mud spill at Ajka, Hungary, in 2010 released 1 million m(3) of caustic red mud into the surrounding area with devastating results. Aerobic and anaerobic batch experiments and solid phase extraction techniques were used to assess the impact of red mud addition on the mobility of Cu and Ni in soils from near the Ajka spill site. Red mud addition increases aqueous dissolved organic carbon (DOC) concentrations due to soil alkalisation, and this led to increased mobility of Cu and Ni complexed to organic matter. With Ajka soils, more Cu was mobilised by contact with red mud than Ni, despite a higher overall Ni concentration in the solid phase. This is most probably because Cu has a higher affinity to form complexes with organic matter than Ni. In aerobic experiments, contact with the atmosphere reduced soil pH via carbonation reactions, and this reduced organic matter dissolution and thereby lowered Cu/Ni mobility. These data show that the mixing of red mud into organic rich soils is an area of concern, as there is a potential to mobilise Cu and Ni as organically bound complexes, via soil alkalisation. This could be especially problematic in locations where anaerobic conditions can prevail, such as wetland areas contaminated by the spill.
NASA Astrophysics Data System (ADS)
Clark, F. R.; McKee, B. A.; Duncan, D. D.
2002-12-01
Particulate and dissolved phases of a suite of metals and radionuclides were analyzed in fluid mud samples collected during a time series. This time series was taken during the passage of a winter storm on the Atchafalaya Shelf off the coast of Louisiana. The shelf receives an estimated 30% of the flow of the Mississippi River from its distributary, the Atchafalaya River. This input contributes a high sediment load to the shelf. Frequent winter storms provide shear stress to resuspend sediments and form fluid mud. Samples of fluid mud and overlying water were collected every two hours for 56 hours. Meteorological data as well as turbidity measurements by OBS were collected throughout the study. Bottom sediments were also collected before and after the time series. Partitioning effects were investigated on Be7, Th234, and Pb210 by gamma spectroscopy. These effects were also studied on several redox-sensitive metals, including Fe, Mn, Mo, Te, Re, U, Al, Ti, and V by ICP-MS analysis. Preliminary results indicate a rapid establishment of reducing conditions in fluid mud immediately overlying the seabed. These conditions persist until the suspended sediments in the fluid mud settle, and the fluid mud dissipates. The recurrence of storm front passages and their subsequent fluid mud formation cause repeated cycling from oxic to suboxic conditions in these coastal bottom waters. This redox cycling could potentially alter the fates of redox-sensitive metals, especially those associated with metal oxide carrier phases.
Lime-mud layers in high-energy tidal channels: A record of hurricane deposition
NASA Astrophysics Data System (ADS)
Shinn, Eugene A.; Steinen, Randolph P.; Dill, Robert F.; Major, Richard
1993-07-01
During or immediately following the transit of Hurricane Andrew (August 23-24, 1992) across the northern part of the Great Bahama Bank, thin laminated beds of carbonate mud were deposited in high-energy subtidal channels (4 m depth) through the ooid shoals of south Cat Cay and Joulters Cays. During our reconnaissance seven weeks later, we observed lime-mud beds exposed in the troughs of submarine oolite dunes and ripples. The mud layers were underlain and locally covered by ooid sand. The mud beds were lenticular and up to 5 cm thick. Their bases cast the underlying rippled surface. The layers were composed of soft silt- and sand-sized pellets and peloids and in some areas contained freshly preserved Thalassia blades and other organic debris along planes of lamination. The beds had a gelatinous consistency and locally had been penetrated by burrowers and plants. Layers of lime mud had also settled on bioturbated, plant-stabilized flats and in lagoonal settings but were quickly reworked and made unrecognizable by the burrowing of organisms. Thicker, more cohesive (and therefore older) mud beds and angular mud fragments associated with ooids from Joulters Cays have similar characteristics but lack fresh plant fragments. We infer that these older beds were similarly deposited and thus record the passage of previous hurricanes or tropical storms. Storm layers are preserved within channel sediments because migrating ooids prevent attack by the burrowing activity off organisms.
Limitations of microbial hydrocarbon degradation at the Amon Mud Volcano (Nile Deep Sea Fan)
NASA Astrophysics Data System (ADS)
Felden, J.; Lichtschlag, A.; Wenzhöfer, F.; de Beer, D.; Feseker, T.; Pop Ristova, P.; de Lange, G.; Boetius, A.
2013-01-01
The Amon mud volcano (MV), located at 1250 m water depth on the Nile Deep Sea Fan, is known for its active emission of methane and non-methane hydrocarbons into the hydrosphere. Previous investigations showed a low efficiency of hydrocarbon-degrading anaerobic microbial communities inhabiting the Amon MV center in the presence of sulphate and hydrocarbons in the seeping subsurface fluids. By comparing spatial and temporal patterns of in situ biogeochemical fluxes, temperature gradients, pore water composition and microbial activities over three years, we investigated why the activity of anaerobic hydrocarbon degraders can be low despite high energy supplies. We found that the central dome of the Amon MV, as well as a lateral mud flow at its base, showed signs of recent exposure of hot subsurface muds lacking active hydrocarbon degrading communities. In these highly disturbed areas, anaerobic degradation of methane was less than 2% of the methane flux. Rather high oxygen consumption rates compared to low sulphide production suggest a faster development of more rapidly growing aerobic hydrocarbon degraders in highly disturbed areas. In contrast, the more stabilized muds surrounding the central gas and fluid conduits hosted active anaerobic hydrocarbon-degrading microbial communities. Furthermore, within three years, cell numbers and hydrocarbon degrading activity increased at the gas-seeping sites. The low microbial activity in the hydrocarbon-vented areas of Amon mud volcano is thus a consequence of kinetic limitations by heat and mud expulsion, whereas most of the outer mud volcano area is limited by hydrocarbon transport.
The report of the Gravity Field Workshop
NASA Astrophysics Data System (ADS)
Smith, D. E.
1982-04-01
A Gravity Field Workshop was convened to review the actions which could be taken prior to a GRAVSAT mission to improve the Earth's gravity field model. This review focused on the potential improvements in the Earth's gravity field which could be obtained using the current satellite and surface gravity data base. In particular, actions to improve the quality of the gravity field determination through refined measurement corrections, selected data augmentation and a more accurate reprocessing of the data were considered. In addition, recommendations were formulated which define actions which NASA should take to develop the necessary theoretical and computation techniques for gravity model determination and to use these approaches to improve the accuracy of the Earth's gravity model.
Assessing Possible Improvements in NATO’s Non-Strategic Nuclear Deterrence Forces
2017-12-01
QUESTION Currently, the only U.S. nuclear weapon based in Europe is the B-61 gravity bomb . The B-61 could be delivered by U.S. and Allied fighter-bomber...currently consists of only air-delivered B-61 gravity bombs . This thesis therefore addresses a little- studied topic of growing importance. Literature on...Postgraduate School, 1989), 53–4, http://hdl.handle.net/10945/29008. 6 would not be possible when using DCA to deliver a B-61 gravity bomb
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mud Slough. 117.177 Section 117.177 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements California § 117.177 Mud Slough. The draw of the Union Pacific...
The Mud Center: Recapturing Childhood.
ERIC Educational Resources Information Center
Jensen, Becky J.; Bullard, Julie A.
2002-01-01
Describes a Montana child development center's creation of an area in which children could enjoy messy, creative, sensory experiences playing with mud and a wide variety of outdoor props. Discusses how mud play contributed to young children's emerging interests and provided opportunities for expressing creativity, enhancing fine motor skills, and…
Teaching Ecological Interactions with Mud Dauber Nests.
ERIC Educational Resources Information Center
Matthews, Robert W.
1997-01-01
Describes the use of mud dauber wasp nests in laboratory activities in ecology and behavior and life science classes. Provides students with an opportunity to develop and practice basic skills including dissection, identification, observation, measurement, and communication. Discusses the life of mud daubers, obtaining and storing nests,…
NASA Astrophysics Data System (ADS)
La Rocca, Michele; Adduce, Claudia; Sciortino, Giampiero; Pinzon, Allen Bateman
2008-10-01
The dynamics of a three-dimensional gravity current is investigated by both laboratory experiments and numerical simulations. The experiments take place in a rectangular tank, which is divided into two square reservoirs with a wall containing a sliding gate of width b. The two reservoirs are filled to the same height H, one with salt water and the other with fresh water. The gravity current starts its evolution as soon as the sliding gate is manually opened. Experiments are conducted with either smooth or rough surface on the bottom of the tank. The bottom roughness is created by gluing sediment material of different diameters to the surface. Five diameter values for the surface roughness and two salinity conditions for the fluid are investigated. The mathematical model is based on shallow-water theory together with the single-layer approximation, so that the model is strictly hyperbolic and can be put into conservative form. Consequently, a finite-volume-based numerical algorithm can be applied. The Godunov formulation is used together with Roe's approximate Riemann solver. Comparisons between the numerical and experimental results show satisfactory agreement. The behavior of the gravity current is quite unusual and cannot be interpreted using the usual model framework adopted for two-dimensional and axisymmetric gravity currents. Two main phases are apparent in the gravity current evolution; during the first phase the front velocity increases, and during the second phase the front velocity decreases and the dimensionless results, relative to the different densities, collapse onto the same curve. A systematic discrepancy is seen between the numerical and experimental results, mainly during the first phase of the gravity current evolution. This discrepancy is attributed to the limits of the mathematical formulation, in particular, the neglect of entrainment in the mathematical model. An interesting result arises from the influence of the bottom surface roughness; it both reduces the front velocity during the second phase of motion and attenuates the differences between the experimental and numerical front velocities during the first phase of motion.
NASA Astrophysics Data System (ADS)
Azhikodan, Gubash; Yokoyama, Katsuhide
2018-03-01
The erosion and deposition dynamics of fine sediment in a highly turbid estuarine channel were successfully surveyed during the period from August 29 to September 12, 2009 using an echo sounder in combination with a high-resolution acoustic Doppler current profiler. Field measurements were conducted focusing on the tide driven dynamics of suspended sediment concentration (SSC), and fluid mud at the upstream of the macrotidal Chikugo river estuary during semidiurnal and fortnightly tidal cycles. Morphological evolution was observed especially during the spring tide over a period of two weeks. The elevation of the channel bed was stable during neap tide, but it underwent fluctuations when the spring tide occurred owing to the increase in the velocity and shear stress. Two days of time lag were observed between the maximum SSC and peak tidal flow, which resulted in the asymmetry between neap-to-spring and spring-to-neap transitions. During the spring tide, a hysteresis loop was observed between shear stress and SSC, and its direction was different during flood and ebb tides. Although both fine sediments and flocs were dominant during flood tides, only fine sediments were noticed during ebb tides. Hence, the net elevation change in the bed was positive, and sedimentation took place during the semilunar tidal cycle. Finally, a bed of consolidated mud was deposited on the initial bed, and the height of the channel bed increased by 0.9 m during the two-week period. The observed hysteretic effect between shear stress and SSC during the spring tides, and the asymmetrical neap-spring-neap tidal cycle influenced the near-bed sediment dynamics of the channel, and led to the formation of a fluid mud layer at the bottom of the river.
A sediment-dispersal model for the South Texas continental shelf, northwest Gulf of Mexico
Shideler, G.L.
1978-01-01
Textural-distribution patterns of sea-floor sediments on the South Texas continental shelf between Matagorda Bay and the U.S.-Mexico international boundary were evaluated as part of a regional environmental-studies program. Sediment textural gradients support a conceptual model for the regional sediment-dispersal system, which is characterized by both net offshore transport and net south-trending coastwise transport components on a wind-dominated shelf. Coastwise transport results in the net southward migration of both palimpsest sandy mud composing the ancestral Brazos-Colorado delta flank in the northern sector, and modern mud composing the central sector; these migrating sediments are encroaching southward onto immobile relict muddy sands composing the ancestral Rio Grande delta in the southern sector. In the proposed model, the suspension transport of modern silt-enriched mud derived mainly from coastal sources is the dominant dispersal mechanism. Net offshore transport is attributed both to diffusion, and to the advective ebb-tide discharge of turbid lagoonal-estuarine waters from coastal inlets. Net southward transport is attributed mainly to advection by seasonally residual coastwise drift currents reflecting a winter-dominated hydraulic regime. Frequent winter storms characterized by relatively high-speed northerly winds that accompany the passage of cold fronts appear to be dominant regional dispersal agents. ?? 1978.
ADCP measurements of gravity currents in the Chicago River, Illinois
Garcia, C.M.; Oberg, K.; Garcia, M.H.
2007-01-01
A unique set of observations of stratified flow phenomena in the Chicago River was made using an upward-looking acoustic Doppler current profiler (ADCP) during the period November 20, 2003 to February 1, 2004. Water density differences between the Chicago River and its North Branch (NB) seem to be responsible for the development of gravity currents. With the objective of characterizing the occurrence, frequency, and evolution of such currents, the ADCP was configured to continuously collect high-resolution water velocity and echo intensity profiles in the Chicago River at Columbus Drive. During the observation period, 28 gravity current events were identified, lasting a total of 77% of the time. Sixteen of these events were generated by underflows from the NB and 12 of these events were generated by overflows from the NB. On average, the duration of the underflow and overflow events was 52.3 and 42.1 h, respectively. A detailed analysis of one underflow event, which started on January 7, 2004, and lasted about 65h, was performed. This is the first time that ADCP technology has been used to continuously monitor gravity currents in a river. ?? 2007 ASCE.
Lobe-cleft instability in the buoyant gravity current generated by estuarine outflow
NASA Astrophysics Data System (ADS)
Horner-Devine, Alexander R.; Chickadel, C. Chris
2017-05-01
Gravity currents represent a broad class of geophysical flows including turbidity currents, powder avalanches, pyroclastic flows, sea breeze fronts, haboobs, and river plumes. A defining feature in many gravity currents is the formation of three-dimensional lobes and clefts along the front and researchers have sought to understand these ubiquitous geophysical structures for decades. The prevailing explanation is based largely on early laboratory and numerical model experiments at much smaller scales, which concluded that lobes and clefts are generated due to hydrostatic instability exclusively in currents propagating over a nonslip boundary. Recent studies suggest that frontal dynamics change as the flow scale increases, but no measurements have been made that sufficiently resolve the flow structure in full-scale geophysical flows. Here we use thermal infrared and acoustic imaging of a river plume to reveal the three-dimensional structure of lobes and clefts formed in a geophysical gravity current front. The observed lobes and clefts are generated at the front in the absence of a nonslip boundary, contradicting the prevailing explanation. The observed flow structure is consistent with an alternative formation mechanism, which predicts that the lobe scale is inherited from subsurface vortex structures.
Titanium leaching from red mud by diluted sulfuric acid at atmospheric pressure.
Agatzini-Leonardou, S; Oustadakis, P; Tsakiridis, P E; Markopoulos, Ch
2008-09-15
Laboratory-scale research has focused on the recovery of titanium from red mud, which is obtained from bauxite during the Bayer process for alumina production. The leaching process is based on the extraction of this element with diluted sulfuric acid from red mud under atmospheric conditions and without using any preliminary treatment. Statistical design and analysis of experiments were used, in order to determine the main effects and interactions of the leaching process factors, which were: acid normality, temperature and solid to liquid ratio. The titanium recovery efficiency on the basis of red mud weight reached 64.5%. The characterization of the initial red mud, as well as this of the leached residues was carried out by X-ray diffraction, TG-DTA and scanning electron microscopy.
Development of new test procedures for measuring fine and coarse aggregates specific gravity.
DOT National Transportation Integrated Search
2009-09-01
The objective of the research is to develop and evaluate new test methods at determining the specific gravity and absorption of both fine and coarse aggregates. Current methods at determining the specific gravity and absorption of fine and coarse agg...
Novel microbial communities of the Haakon Mosby mud volcano and their role as a methane sink.
Niemann, Helge; Lösekann, Tina; de Beer, Dirk; Elvert, Marcus; Nadalig, Thierry; Knittel, Katrin; Amann, Rudolf; Sauter, Eberhard J; Schlüter, Michael; Klages, Michael; Foucher, Jean Paul; Boetius, Antje
2006-10-19
Mud volcanism is an important natural source of the greenhouse gas methane to the hydrosphere and atmosphere. Recent investigations show that the number of active submarine mud volcanoes might be much higher than anticipated (for example, see refs 3-5), and that gas emitted from deep-sea seeps might reach the upper mixed ocean. Unfortunately, global methane emission from active submarine mud volcanoes cannot be quantified because their number and gas release are unknown. It is also unclear how efficiently methane-oxidizing microorganisms remove methane. Here we investigate the methane-emitting Haakon Mosby Mud Volcano (HMMV, Barents Sea, 72 degrees N, 14 degrees 44' E; 1,250 m water depth) to provide quantitative estimates of the in situ composition, distribution and activity of methanotrophs in relation to gas emission. The HMMV hosts three key communities: aerobic methanotrophic bacteria (Methylococcales), anaerobic methanotrophic archaea (ANME-2) thriving below siboglinid tubeworms, and a previously undescribed clade of archaea (ANME-3) associated with bacterial mats. We found that the upward flow of sulphate- and oxygen-free mud volcano fluids restricts the availability of these electron acceptors for methane oxidation, and hence the habitat range of methanotrophs. This mechanism limits the capacity of the microbial methane filter at active marine mud volcanoes to <40% of the total flux.
Effect of strong acids on red mud structural and fluoride adsorption properties.
Liang, Wentao; Couperthwaite, Sara J; Kaur, Gurkiran; Yan, Cheng; Johnstone, Dean W; Millar, Graeme J
2014-06-01
The removal of fluoride using red mud has been improved by acidifying red mud with hydrochloric, nitric and sulphuric acid. The acidification of red mud causes sodalite and cancrinite phases to dissociate, confirmed by the release of sodium and aluminium into solution as well as the disappearance of sodalite bands and peaks in infrared and X-ray diffraction data. The dissolution of these mineral phases increases the amount of available iron and aluminium oxide/hydroxide sites that are accessible for the adsorption of fluoride. However, concentrated acids have a negative effect on adsorption due to the dissolution of these iron and aluminium oxide/hydroxide sites. The removal of fluoride is dependent on the charge of iron and aluminium oxide/hydroxides on the surface of red mud. Acidifying red mud with hydrochloric, nitric and sulphuric acid resulted in surface sites of the form ≡SOH2(+) and ≡SOH. Optimum removal is obtained when the majority of surface sites are in the form ≡SOH2(+) as the substitution of a fluoride ion does not cause a significant increase in pH. This investigation shows the importance of having a low and consistent pH for the removal of fluoride from aqueous solutions using red mud. Copyright © 2014 Elsevier Inc. All rights reserved.
Capping hazardous red mud using acidic soil with an embedded layer of zeolite for plant growth.
Ma, Yingqun; Si, Chunhua; Lin, Chuxia
2014-01-01
A nearly three-year microcosm experiment was conducted to test the effectiveness of capping red mud using acidic soil with an embedded layer of zeolite in sustaining the growth of a grass species. This 'sandwich-structured' design allowed self-sustaining growth of the plants under rain-fed conditions no matter whether the underlying red mud was neutralized or not. During the initial stage, the plants grew better when the red mud was not neutralized with MgCl2 probably due to pH rise in the root zone. Neutralization of red mud led to salinization and pH decrease in the root zone. However, the difference in plant growth performance between these scenarios became less remarkable over time due to gradual improvement of soil conditions in the neutralized scenarios. Continuous leaching of soluble salts and alkali by rainwater extended the root zone to the red mud layer. As a result of vegetative production, soil organic matter rapidly accumulated. This, combined with increase in pH and decrease in salinity, markedly facilitated microbial activities and consequently improved the supply of nutrients. This study provides abasis for field-scale experimental design that will have implications for effectively establishing vegetative cover in red mud disposal sites to control dust hazards.
Automatic mouse ultrasound detector (A-MUD): A new tool for processing rodent vocalizations.
Zala, Sarah M; Reitschmidt, Doris; Noll, Anton; Balazs, Peter; Penn, Dustin J
2017-01-01
House mice (Mus musculus) emit complex ultrasonic vocalizations (USVs) during social and sexual interactions, which have features similar to bird song (i.e., they are composed of several different types of syllables, uttered in succession over time to form a pattern of sequences). Manually processing complex vocalization data is time-consuming and potentially subjective, and therefore, we developed an algorithm that automatically detects mouse ultrasonic vocalizations (Automatic Mouse Ultrasound Detector or A-MUD). A-MUD is a script that runs on STx acoustic software (S_TOOLS-STx version 4.2.2), which is free for scientific use. This algorithm improved the efficiency of processing USV files, as it was 4-12 times faster than manual segmentation, depending upon the size of the file. We evaluated A-MUD error rates using manually segmented sound files as a 'gold standard' reference, and compared them to a commercially available program. A-MUD had lower error rates than the commercial software, as it detected significantly more correct positives, and fewer false positives and false negatives. The errors generated by A-MUD were mainly false negatives, rather than false positives. This study is the first to systematically compare error rates for automatic ultrasonic vocalization detection methods, and A-MUD and subsequent versions will be made available for the scientific community.
Biological properties of mud extracts derived from various spa resorts.
Spilioti, Eliana; Vargiami, Margarita; Letsiou, Sophia; Gardikis, Konstantinos; Sygouni, Varvara; Koutsoukos, Petros; Chinou, Ioanna; Kassi, Eva; Moutsatsou, Paraskevi
2017-08-01
Spa resorts are known for thousands of years for their healing properties and have been empirically used for the treatment of many inflammatory conditions. Mud is one of the most often used natural materials for preventive, healing and cosmetic reasons and although it has been used since the antiquity, little light has been shed on its physical, chemical and biological properties. In this study we examined the effect of mud extracts on the expression of adhesion molecules (CAMs) by endothelial cells as well as their effects on monocyte adhesion to activated endothelial cells. Most of mud extracts inhibited the expression of VCAM-1 by endothelial cells and reduced monocyte adhesion to activated endothelial cells, indicating a potent anti-inflammatory activity. Furthermore, the mud extracts were tested for their antimicrobial activity; however, most of them appeared inactive against S. aureus and S. epidermidis. One of the mud extracts (showing the best stabilization features) increased significantly the expression of genes involved in cell protection, longevity and hydration of human keratinocytes, such as, collagen 6A1, forkhead box O3, sirtuin-1, superoxide dismutase 1 and aquaporin-3. The present study reveals that mud exerts important beneficial effects including anti-inflammatory and anti-aging activity as well as moisturizing effects, implicating important cosmeceutical applications.
Characterization of red mud-epoxy intumescent char using surface imaging and micro analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arogundade, A. I., E-mail: ajiunolorioba@gmail.com; Megat-Yusoff, P. S. M., E-mail: puteris@petronas.com.my; Faiz, A.
In this study, red mud (RM), an oxide waste was proposed as reinforcing, synergistic filler for the traditional epoxy intumescent coating (IC). 5.5 wt% of acid-modified and unmodified red mud were introduced into the basic intumescent formulation of ammonium polyphosphate (APP), pentaerythritol (PER) and melamine (MEL). In order to predict effect of modification on its suitability, Field emission electron scanning microscopy and Fourier transform infra red were used to obtain detailed characteristics such as the cell size, pore distribution, homogeneity and chemical composition of the red mud-epoxy carbonaceous char. Both acid-modified and unmodified RM-filled ICs produced chars with smaller andmore » more closely packed cells compared to chars from the unfilled coating. Both coating types had hard carbonaceous metal phosphate coverings that could act as heat barriers. The unmodified red mud was found to be antagonistic to the intumescent action with an expansion of only 2 times the initial thickness. The leached, low iron-red mud produced an expansion of 15 times the initial thickness, but possessed a hollow interior. From these findings, it may be deduced that while acid leaching of red mud may improve intumescent expansion, it would be necessary to optimize the percent filler loading to improve residual mass.« less
Lazar, Cassandre Sara; Parkes, R John; Cragg, Barry A; L'Haridon, Stéphane; Toffin, Laurent
2011-08-01
Submarine mud volcanoes are a significant source of methane to the atmosphere. The Napoli mud volcano, situated in the brine-impacted Olimpi Area of the Eastern Mediterranean Sea, emits mainly biogenic methane particularly at the centre of the mud volcano. Temperature gradients support the suggestion that Napoli is a cold mud volcano with moderate fluid flow rates. Biogeochemical and molecular genetic analyses were carried out to assess the methanogenic activity rates, pathways and diversity in the hypersaline sediments of the centre of the Napoli mud volcano. Methylotrophic methanogenesis was the only significant methanogenic pathway in the shallow sediments (0-40 cm) but was also measured throughout the sediment core, confirming that methylotrophic methanogens could be well adapted to hypersaline environments. Hydrogenotrophic methanogenesis was the dominant pathway below 50 cm; however, low rates of acetoclastic methanogenesis were also present, even in sediment layers with the highest salinity, showing that these methanogens can thrive in this extreme environment. PCR-DGGE and methyl coenzyme M reductase gene libraries detected sequences affiliated with anaerobic methanotrophs (mainly ANME-1) as well as Methanococcoides methanogens. Results show that the hypersaline conditions in the centre of the Napoli mud volcano influence active biogenic methane fluxes and methanogenic/methylotrophic diversity. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.
Yilbas, Bekir Sami.; Ali, Haider; Khaled, Mazen M.; Al-Aqeeli, Nasser; Abu-Dheir, Numan; Varanasi, Kripa K.
2015-01-01
Recent developments in climate change have increased the frequency of dust storms in the Middle East. Dust storms significantly influence the performances of solar energy harvesting systems, particularly (photovoltaic) PV systems. The characteristics of the dust and the mud formed from this dust are examined using various analytical tools, including optical, scanning electron, and atomic force microscopies, X-ray diffraction, energy spectroscopy, and Fourier transform infrared spectroscopy. The adhesion, cohesion and frictional forces present during the removal of dry mud from the glass surface are determined using a microtribometer. Alkali and alkaline earth metal compounds in the dust dissolve in water to form a chemically active solution at the glass surface. This solution modifies the texture of the glass surface, thereby increasing the microhardness and decreasing the transmittance of the incident optical radiation. The force required to remove the dry mud from the glass surface is high due to the cohesive forces that result from the dried mud solution at the interface between the mud and the glass. The ability altering the characteristics of the glass surface could address the dust/mud-related limitations of protective surfaces and has implications for efficiency enhancements in solar energy systems. PMID:26514102
Source Signature of Sr Isotopes in Fluids Emitting From Mud volcanoes in Taiwan
NASA Astrophysics Data System (ADS)
Chung, C.; You, C.; Chao, H.
2003-12-01
Located at the boundary between the Philippine Sea Plate and the Asia Continental Plate, abundance of mud volcanoes were erupted on land in Taiwan. According to their occurrences and associated tectonic settings, these mud volcanoes were classified into four groupies. The group (I) mud volcanoes are located in the western coastal plane, whereas group (II) and (III) are situated near the Kutinkung anticline axis and the Chishan fault respectively. The group (IV) mud volcanoes are discovered at the Coastal Range. Although there are numerous studies focused on morphology, possible fluid migration paths and sources are poorly understood. We have collected and analyzed major ions and Sr isotopic ratios in fluids separated from various mud volcanoes in Taiwan. Chemical contents of these fluids were measured by IC and the emitted gasses were analyzed by GC. The Sr concentrations in these fluids were determined using AA and the isotopic compositions were analyzed by TIMS. The dominated ions in fluids are Na and Cl which account for 98% of dissolved materials. All fluids show similar Na/Cl ratios(0.7-0.8), slightly higher than seawater but each group has unique Sr isotopic signature. Waters expelled from group I mud volcanoes featured with low salinity and high Sr isotopic ratios ranged from 0.71150 to 0.71175. Groups II and III were outcroped in the Kutinkung formation but show distinctive chemical compositions. Group II fluids have four times Cl concentrations(358-522mM) compared with those of group III(85-162mM). The latter fluids appear to be more radiogenic(0.71012- 0.71075) indicating possible influence due to water-rock interactions. Low 87Sr/86Sr(0.70692-0.70939) is typical characteristic of mud volcano fluids in group IV where large Mg and K depletion were discovered, suggesting effects due to sediment diagenetic processes. The chemical compositions of mud volcano associated gasses show similar distribution pattern. The major gas constituents in mud volcano zones II and III are methane(>80%), air(1-10%) and carbon dioxide(1-5%). Gases collected from zone IV display significantly higher air content(5-20%) with low carbon dioxide(<0.2%). These results are useful for gaining a better understanding of mud volcano fluid sources.
Jones, B E H; Haynes, R J; Phillips, I R
2012-03-01
The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated mud had a marked depressive effect on both top and root growth. The significant positive effect of compost was attributed to substantial inputs of K and marked reductions in the Na/K ratio in soil solution while the depressive effect of RMC was attributed to its greater alkalinity and consequently higher concentrations of HCO(3)(-) in solution. Copyright © 2011 Elsevier Ltd. All rights reserved.
Experimental Evidence that Abrasion of Carbonate Sand is a Significant Source of Carbonate Mud
NASA Astrophysics Data System (ADS)
Trower, L.; Kivrak, L.; Lamb, M. P.; Fischer, W. W.
2017-12-01
Carbonate mud is a major sedimentary component of modern and ancient tropical carbonate environments, yet its enigmatic origin remains debated. Early views on the origin of carbonate mud considered the abrasion of carbonate sand during sediment transport as a possible mechanism. In recent decades, however, prevailing thought has generally settled on a binary explanation: 1) precipitation of aragonite needles within the water column, and 2) post-mortem dispersal of biological aragonite, in particular from algae, and perhaps aided by fish. To test these different hypotheses, we designed a model and a set of laboratory experiments to quantify the rates of mud production associated with sediment transport. We adapted a recent model of ooid abrasion rate to predict the rate of mud production by abrasion of carbonate sand as a function of grain size and sediment transport mode. This model predicts large mud production rates, ranging from 103 to 104 g CaCO3/m2/yr for typical grain sizes and transport conditions. These rate estimates are at least one order of magnitude more rapid than the 102 g CaCO3/m2/yr estimates for other mechanisms like algal biomineralization, indicating that abrasion could produce much larger mud fluxes per area as other mechanisms. We tested these estimates using wet abrasion mill experiments; these experiments generated mud through mechanical abrasion of both ooid and skeletal carbonate sand for grain sizes ranging from 250 µm to >1000 µm over a range of sediment transport modes. Experiments were run in artificial seawater, including a series of controls demonstrating that no mud was produced via homogenous nucleation and precipitation in the absence of sand. Our experimental rates match the model predictions well, although we observed small systematic differences in rates between abrasion ooid sand and skeletal carbonate sand that likely stems from innate differences in grain angularity. Electron microscopy of the experimental products revealed aragonite needles 1-3 µm in length identical to those described in carbonate mud from a range of modern environments. Our results suggest that abrasion during bed load and suspended load transport of carbonate sand, even over small areas, is likely a significant potential source of carbonate mud in both modern and ancient carbonate environments.
NASA Astrophysics Data System (ADS)
Serrano, Oscar; Lavery, Paul S.; Duarte, Carlos M.; Kendrick, Gary A.; Calafat, Antoni; York, Paul H.; Steven, Andy; Macreadie, Peter I.
2016-09-01
The emerging field of blue carbon science is seeking cost-effective ways to estimate the organic carbon content of soils that are bound by coastal vegetated ecosystems. Organic carbon (Corg) content in terrestrial soils and marine sediments has been correlated with mud content (i.e., silt and clay, particle sizes < 63 µm), however, empirical tests of this theory are lacking for coastal vegetated ecosystems. Here, we compiled data (n = 1345) on the relationship between Corg and mud contents in seagrass ecosystems (79 cores) and adjacent bare sediments (21 cores) to address whether mud can be used to predict soil Corg content. We also combined these data with the δ13C signatures of the soil Corg to understand the sources of Corg stores. The results showed that mud is positively correlated with soil Corg content only when the contribution of seagrass-derived Corg to the sedimentary Corg pool is relatively low, such as in small and fast-growing meadows of the genera Zostera, Halodule and Halophila, and in bare sediments adjacent to seagrass ecosystems. In large and long-living seagrass meadows of the genera Posidonia and Amphibolis there was a lack of, or poor relationship between mud and soil Corg content, related to a higher contribution of seagrass-derived Corg to the sedimentary Corg pool in these meadows. The relatively high soil Corg contents with relatively low mud contents (e.g., mud-Corg saturation) in bare sediments and Zostera, Halodule and Halophila meadows was related to significant allochthonous inputs of terrestrial organic matter, while higher contribution of seagrass detritus in Amphibolis and Posidonia meadows disrupted the correlation expected between soil Corg and mud contents. This study shows that mud is not a universal proxy for blue carbon content in seagrass ecosystems, and therefore should not be applied generally across all seagrass habitats. Mud content can only be used as a proxy to estimate soil Corg content for scaling up purposes when opportunistic and/or low biomass seagrass species (i.e., Zostera, Halodule and Halophila) are present (explaining 34 to 91 % of variability), and in bare sediments (explaining 78 % of the variability). The results obtained could enable robust scaling up exercises at a low cost as part of blue carbon stock assessments.
NASA Astrophysics Data System (ADS)
Coratza, Paola; Albarello, Dario; Cipriani, Anna; Cantucci, Barbara; Castaldini, Doriano; Conventi, Marzia; Dadomo, Andrea; De Nardo, Maria Teresa; Macini, Paolo; Martinelli, Giovanni; Mesini, Ezio; Papazzoni, Cesare Andrea; Quartieri, Simona; Ricci, Tullio; Santagata, Tommaso; Sciarra, Alessandra; Vezzalini, Giovanna
2017-04-01
Mud volcanoes are emissions of cold mud due to the ascent to the surface of salty and muddy waters mixed with gaseous (methane) and, in minor part, fluid hydrocarbons (petroleum veils) along faults and fractures. In the Northern Apennines mud volcanoes are closely linked to the active tectonic compression associated with thrusts of regional importance. They are mostly cone-shaped and show variable geometry and size, ranging from one to few metres, and are located in 19 sites in the northwestern part of the Apennines. Particularly noteworthy is the Nirano mud volcano field, located in the Fiorano Modenese district, which, with a surface area of approximately 75,000 m2, is one of the best developed and largest mud volcano field of the entire Italian territory and among the largest in Europe; it is thus protected as natural reserve (Salse di Nirano) since 1982. The Nirano mud volcanoes are found at the bottom of an elliptical depression, interpreted as a collapse-like structure (caldera) that may have developed in response to the deflation of a shallow mud chamber triggered by several ejections and evacuation of fluid sediments. There are several individual or multiple cones within the field of the mud volcanoes of Nirano, with a rather discontinuous activity; apparatuses become dormant or even extinct whereas new vents can appear in other spots. In the research here presented about 50 vents have been mapped and few of them appeared in May 2016. The mud volcanoes of the region have been known since a long time and have always aroused great interest due to their outstanding scenic value, and, in the past the mud volcano emissions have been used in many ways. Beside their cultural value, the mud volcanoes of the study area represent a tourist attractiveness as testified by the increasing number of visitors (e.g. about 70,000 visitors in 2015 in the Salse di Nirano Natural Reserve). Numerous initiatives, targeted at various potential users, have been developed in the last decades. In particular, tourist environmental maps, geotourism maps, books in hard copy and digital format, videos, virtual flights, multimedia and audio CDs have been implemented. Although the hazard from mud volcanoes is generally low, sometimes they may lead to sudden and violent eruptions and isolated casualties have been reported. Very notable case in this regard is the event that occurred in September 2014 in the Natural Reserve of Macalube di Aragona in Sicily where a mud volcano erupted, with an ejection of mud up to about 20 m above the ground and causing the burial of two children killing them. When a given geological site acquires a tourism value, it is necessary to assess the possible natural hazard processes which might threaten the safety of visitors. In particular, fast-occurring processes might directly involve tourists in proximity of the site of interest or along access roads and footpaths. In this context, multidisciplinary research, aiming at analysing the causes and understanding triggering mechanisms of paroxysmal and dangerous phenomena in the Natural Reserve of Nirano, are in progress, funded by the Fiorano municipality. The research team is composed by experts of different disciplines (geology, geomorphology, geophysics, geochemistry, palaeontology, mineralogy, topography) from different institutions. The first results of the multidisciplinary research here presented seem to confirm that no significant and dangerous phenomena can affect visitors along the pathways of the Reserve.
Gravity-directed calcium current in germinating spores of Ceratopteris richardii
NASA Technical Reports Server (NTRS)
Chatterjee, A.; Porterfield, D. M.; Smith, P. S.; Roux, S. J.
2000-01-01
Gravity directs the early polar development in single cells of Ceratopteris richardii Brogn. It acts over a limited period of time during which it irreversibly determines the axis of the spore cell's development. A self-referencing calcium selective electrode was utilized to record the net movement of calcium across the cell membrane at different positions around the periphery of the spore during the period in which gravity orients the polarity of the spore. A movement of calcium into the cell along the bottom and out of the cell along the top was detected. This movement was specific, polarized, and strongest in a direction that opposed the vector of gravity. Treatment with nifedipine, a calcium-channel blocker, diminished the calcium current and caused the cell to lose its responsiveness to the orienting influence of gravity. Results shown suggest that calcium plays a crucial role in the ability of a single cell to respond to gravity and in the subsequent establishment of its polarity.
Application of medical X-ray computed tomography in the study of cold-water carbonate mounds
NASA Astrophysics Data System (ADS)
de Mol, L.; Pirlet, H.; van Rooij, D.; Blamart, D.; Cnudde, V.; Duyck, P.; Houbrechts, H.; Jacobs, P.; Henriet, J.-P.; Dufresne 169 Shipboard Party, The Marion
2009-04-01
During the R/V Marion Dufresne 169 'MiCROSYSTEMS' cruise (July 2008) to the El Arraiche mud volcano field in the Gulf of Cadiz cold-water coral mounds were targeted. Four on-mound gravity cores, with a total length of 17.5 m, were obtained for sedimentological and palaeoceanographic analyses in order to unveil the history of the uppermost meters of these cold-water coral build-ups. In parallel, four on-mound cores were taken on approximately the same location for microbiological and biogeochemical analyses. By comparing and correlating both results, more information can be revealed about the processes acting in the dead coral rubble fields which cover these mounds. Computed X-ray tomography (CT) was used for the identification and quantification of the corals inside the gravity cores. Furthermore, this technique is also useful for the investigation of sedimentological features, i.e. bioturbation, porosity, laminations... In this study, cores were scanned using a medical CT scanner on a relative high resolution which allows the three-dimensional visualization of the corals and sedimentological features. Slices were taken every 3 mm with an overlap of 1 mm. Based on these data it was possible to delineate different "CT" facies within the cores. On one hand there are intervals with a high amount of corals and on the other hand zones with a very low amount of corals or even no corals at all. In the first case two different facies can be distinguished: one facies with clearly recognizable, well preserved corals, and the second facies with crushed coral fragments. In both facies the corals are embedded in a homogenous matrix. Different facies could also be defined in the intervals containing little or no corals. For example, a homogenous facies with bioturbations and/or cracks. Also an important observation is the presence of pyrite which appears in all cores at a certain depth. Sometimes the pyrite could be observed in bioturbations or inside the corals. Besides that also the percentage of corals in these gravity cores were quantified using the "Morpho+" software, which was developed at the UGCT (Centre for X-ray Tomography, Ghent University, Belgium). Based on these results, a clear difference can be noticed between the four mounds. On Conger cliff, corals were only observed in the upper 34 cm while in the other locations corals can be found throughout the entire core with significant variations in the amount of corals. Finally, it was possible to identify different species of cold-water corals, namely Lophelia pertusa, Madrepora oculata, Desmophyllum cristagalli and Dendrophyllia. In conjunction with dating and palaeoenvironmental analyses of the corals and the sediment matrix, this can yield valuable information about the build-up of these cold-water coral mounds in the El Arraiche mud volcano field and the palaeoenvironmental characteristics at the time the corals were living.
Thermosyphon Flooding in Reduced Gravity Environments
NASA Technical Reports Server (NTRS)
Gibson, Marc Andrew
2013-01-01
An innovative experiment to study the thermosyphon flooding limits was designed and flown on aparabolic flight campaign to achieve the Reduced Gravity Environments (RGE) needed to obtainempirical data for analysis. Current correlation models of Faghri and Tien and Chung do not agreewith the data. A new model is presented that predicts the flooding limits for thermosyphons inearths gravity and lunar gravity with a 95 confidence level of +- 5W.
NASA Astrophysics Data System (ADS)
Gensac, Erwan; Martinez, Jean-Michel; Vantrepotte, Vincent; Anthony, Edward J.
2016-04-01
Fine-grained sediments supplied to the Ocean by the Amazon River and their transport under the influence of continental and oceanic forcing drives the geomorphic change along the 1500 km-long coast northward to the Orinoco River delta. The aim of this study is to give an encompassing view of the sediment dynamics in the shallow coastal waters from the Amazon River mouth to the Capes region (northern part of the Amapa region of Brazil and eastern part of French Guiana), where large mud banks are formed. Mud banks are the overarching features in the dynamics of the Amazon-Orinoco coast. They start migrating northward in the Capes region. Suspended Particulate Matter (SPM) concentrations were calculated from satellite products (MODIS Aqua and Terra) acquired over the period 2000-2013. The Census-X11 decomposition method used to discriminate short-term, seasonal and long-term time components of the SPM variability has rendered possible a robust analysis of the impact of continental and oceanic forcing. Continental forcing agents considered are the Amazon River water discharge, SPM concentration and sediment discharge. Oceanic forcing comprises modelled data of wind speed and direction, wave height and direction, and currents. A 150 km-long area of accretion is detected at Cabo Norte that may be linked with a reported increase in the river's sediment discharge concurrent with the satellite data study period. We also assess the rate of mud bank migration north of Cabo Norte, and highlight its variability. Although we confirm a 2 km y-1 migration rate, in agreement with other authors, we show that this velocity may be up to 5 km y-1 along the Cabo Orange region, and we highlight the effect of water discharge by major rivers debouching on this coastal mud belt in modulating such rates. Finally, we propose a refined sediment transport pattern map of the region based on our results and of previous studies in the area such as the AMASSEDS programme, and discuss the relationship between sediment transport and accumulation patterns and the coastal geomorphology of this region.
NASA Astrophysics Data System (ADS)
Simoes Correa, Thiago Barreto
Scleractinian cold-water corals are widely distributed in seaways and basins of the North Atlantic Ocean, including the Straits of Florida. These corals can form extensive biogenic mounds, which are biodiversity hotspots in the deep ocean. The processes that lead to the genesis of such cold-water coral mounds and control their distribution and morphology are poorly understood. This work uses an innovative mapping approach that combines 130 km 2 of high resolution geophysical and oceanographic data collected using an Autonomous Underwater Vehicle (AUV) from five cold-water coral habitats in the Straits of Florida. These AUV data, together with ground-truthing observations from eleven submersible dives, are used to investigate fine-scale mound parameters and their relationships with environmental factors. Based on these datasets, automated methods are developed for extracting and analyzing mound morphometrics and coral cover. These analyses reveal that mound density is 14 mound/km 2 for the three surveyed sites on the toe-of-slope of Great Bahama Bank (GBB); this density is higher than previously documented (0.3 mound/km 2) in nearby mound fields. Morphometric analyses further indicate that mounds vary significantly in size, from a meter to up to 110 m in relief, and 81 to 600,000 m2 in footprint area. In addition to individual mounds, cold-water corals also develop in some areas as elongated low-relief ridges that are up to 25 m high and 2000 m long. These ridges cover approximately 60 and 70% of the mapped seafloor from the sites at the center of the Straits and at the base of the Miami Terrace, respectively. Morphometrics and current data analyses across the five surveyed fields indicate that mounds and ridges are not in alignment with the dominant current directions. These findings contradict previous studies that described streamlined mounds parallel to the northward Florida Current. In contrast, this study shows that the sites dominated by coral ridges are influenced by unidirectional flowing current, whereas the mounds on the GBB slope are influenced by tidal current regime. The GBB mounds also experience higher sedimentation rates relative to the sites away from the GBB slope. Sub-surface data document partially or completely buried mounds on the GBB sites. The sediments burying mounds are off-bank material transported downslope by mass gravity flow. Mass gravity transport creates complex slope architecture on the toe-of-slope of GBB, with canyons, slump scars, and gravity flow deposits. Cold-water corals use all three of these features as location for colonization. Coral mounds growing on such pre-existing topography keep up with off-bank sedimentation. In contrast, away from the GBB slope, off-bank sedimentation is absent and coral ridges grow independently of antecedent topography. In the sediment-starved Miami Terrace site, coral ridge initiation is related to a cemented mid-Miocene unconformity. In the center of the Straits, coral ridges and knobs develop over an unconsolidated sand sheet at the tail of the Pourtales drift. Coral features at the Miami Terrace and center of the Straits have intricate morphologies, including waveform and chevron-like ridges, which result from asymmetrical coral growth. Dense coral frameworks and living coral colonies grow preferentially on the current-facing ridge sides in order to optimize food particle capture, whereas coral rubble and mud-sized sediments accumulate in the ridge leesides. Finally, this study provides a method using solely acoustic data for discriminating habitats in which cold-water corals are actively growing. Results from this method can guide future research on and management of cold-water coral ecosystems. Taken together, spatial quantitative analyses of the large-scale, high-resolution integrated surveys indicate that cold-water coral habitats in the Straits of Florida: (1) are significantly more diverse and abundant than previously thought, and (2) can be influenced in their distribution and development by current regime, sedimentation, and/or antecedent topography.
Barthod, J; Rumpel, C; Calabi-Floody, M; Mora, M-L; Bolan, N S; Dignac, M-F
2018-09-15
Alkaline industrial wastes such as red mud and fly ash are produced in large quantities. They may be recycled as bulking agent during composting and vermicomposting, converting organic waste into soil amendments or plant growth media. The aim of this study was to assess the microbial parameters, greenhouse gas emissions and nutrient availability during composting and vermicomposting of household waste with red mud and fly ash 15% (dry weight). CO 2 , CH 4 and N 2 O emissions were monitored during 6 months in controlled laboratory conditions and microbial biomass and phospholipid acids, N and P availability were analysed in the end-products. Higher CO 2 emissions were observed during vermicomposting compared to composting. These emissions were decreased by red mud addition, while fly ash had no effect. Nitrate (NO 3 -N) content of the end-products were more affected by worms than by alkaline materials, while higher ammonium (NH 4 -N) contents were recorded for composts than vermicomposts. Red mud vermicompost showed higher soluble P proportion than red mud compost, suggesting that worm presence can counterbalance P adsorption to the inorganic matrix. Final composts produced with red mud showed no harmful heavy metal concentrations. Adding worms during composting thus improved the product nutrient availability and did not increase metal toxicity. From a practical point of view, this study suggests that for carbon stabilisation and end-product quality, the addition of red mud during composting should be accompanied by worm addition to counterbalance negative effects on nutrient availability. Copyright © 2018. Published by Elsevier Ltd.
Li, Hui; Liu, Yan; Zhou, Yaoyu; Zhang, Jiachao; Mao, Qiming; Yang, Yuan; Huang, Hongli; Liu, Zhaohui; Peng, Qinghui; Luo, Lin
2018-06-04
Highly effective, economical, and replicable ways of Cd-polluted paddy field remediation (in situ) are urgently needed. In this work, a yearlong field experiment (both early and late rice) was conducted to investigate the effects of red mud based passivator [red mud, diatomite, and lime (5:3:2)] on remediation of an acidic Cd-polluted paddy field in Hunan Province. Compared with the control, the addition of red mud based passivator in the early and late rice reduced Cd concentration in each part of the rice plant (with the most significant decrease rate of 59.18% and 72.11% for brown rice in the early rice and late rice seasons respectively). The effect of Cd reduction in the rice plant was persistent in the next growing season. The addition of red mud based passivator also reduced the exchangeable fraction of Cd in the soil and converted the exchangeable fraction into other unavailable fractions. This study demonstrated that the pH in acidic soil increased after the application of red mud based passivator. Furthermore, red mud based passivator had no effect on the concentrations of Olsen-K, Alkaline-N, Olsen-P in the soil, but increased rice grain yield. Overall, the results of this study indicated that the red mud based passivator at 0.6 kg m -2 could be a recommendation for Cd-polluted acidic paddy soil stabilization, and it would be a suitable method for remediation of Cd-polluted acidic paddy soil. Copyright © 2018 Elsevier B.V. All rights reserved.
Struchtemeyer, Christopher G.; Davis, James P.; Elshahed, Mostafa S.
2011-01-01
The Barnett Shale in north central Texas contains natural gas generated by high temperatures (120 to 150°C) during the Mississippian Period (300 to 350 million years ago). In spite of the thermogenic origin of this gas, biogenic sulfide production and microbiologically induced corrosion have been observed at several natural gas wells in this formation. It was hypothesized that microorganisms in drilling muds were responsible for these deleterious effects. Here we collected drilling water and drilling mud samples from seven wells in the Barnett Shale during the drilling process. Using quantitative real-time PCR and microbial enumerations, we show that the addition of mud components to drilling water increased total bacterial numbers, as well as the numbers of culturable aerobic heterotrophs, acid producers, and sulfate reducers. The addition of sterile drilling muds to microcosms that contained drilling water stimulated sulfide production. Pyrosequencing-based phylogenetic surveys of the microbial communities in drilling waters and drilling muds showed a marked transition from typical freshwater communities to less diverse communities dominated by Firmicutes and Gammaproteobacteria. The community shifts observed reflected changes in temperature, pH, oxygen availability, and concentrations of sulfate, sulfonate, and carbon additives associated with the mud formulation process. Finally, several of the phylotypes observed in drilling muds belonged to lineages that were thought to be indigenous to marine and terrestrial fossil fuel formations. Our results suggest a possible alternative exogenous origin of such phylotypes via enrichment and introduction to oil and natural gas reservoirs during the drilling process. PMID:21602366
Struchtemeyer, Christopher G; Davis, James P; Elshahed, Mostafa S
2011-07-01
The Barnett Shale in north central Texas contains natural gas generated by high temperatures (120 to 150°C) during the Mississippian Period (300 to 350 million years ago). In spite of the thermogenic origin of this gas, biogenic sulfide production and microbiologically induced corrosion have been observed at several natural gas wells in this formation. It was hypothesized that microorganisms in drilling muds were responsible for these deleterious effects. Here we collected drilling water and drilling mud samples from seven wells in the Barnett Shale during the drilling process. Using quantitative real-time PCR and microbial enumerations, we show that the addition of mud components to drilling water increased total bacterial numbers, as well as the numbers of culturable aerobic heterotrophs, acid producers, and sulfate reducers. The addition of sterile drilling muds to microcosms that contained drilling water stimulated sulfide production. Pyrosequencing-based phylogenetic surveys of the microbial communities in drilling waters and drilling muds showed a marked transition from typical freshwater communities to less diverse communities dominated by Firmicutes and Gammaproteobacteria. The community shifts observed reflected changes in temperature, pH, oxygen availability, and concentrations of sulfate, sulfonate, and carbon additives associated with the mud formulation process. Finally, several of the phylotypes observed in drilling muds belonged to lineages that were thought to be indigenous to marine and terrestrial fossil fuel formations. Our results suggest a possible alternative exogenous origin of such phylotypes via enrichment and introduction to oil and natural gas reservoirs during the drilling process.
The main objective of the feasibility study described here was to test the hypothesis that properly plugged wells are effectively sealed by drilling mud. In The process of testing the hypothesis, evidence about dynamics of building mud cake on the wellbore-face was obtained, as ...
76 FR 61295 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-04
..., in the same column, in the ninth entry ``Tributary 11'' should read ``West Mud Creek Tributary 11... ``Tributary B'' should read ``West Mud Creek Tributary B''. 12. On the same page, in the same section, in the same table, in the same column, in the eleventh entry ``Tributary M-1'' should read ``West Mud Creek...
Clueless Newbies in the MUDs: An Introduction to Multiple-User Environments.
ERIC Educational Resources Information Center
LeNoir, W. David
1998-01-01
Describes Multiple-User Dungeons (MUDs), multiple-user computer programs that allow participants to interact with others in "real time" exchanges. Discusses their potential in the writing classroom and beyond, and notes their potential for faculty development activities. Offers a list of Internet resources, some actual MUD addresses, and other…
Programming for Fun: MUDs as a Context for Collaborative Learning.
ERIC Educational Resources Information Center
Bruckman, Amy
Multi-User Dungeons (MUDs), are text-based virtual reality environments in which participants separated by great physical distances can communicate and collaborate in programming. Most MUDs started out as adventure games but are quickly being adapted for more "serious" endeavors. This paper presents a case study of the experiences of a…
Shi, Jing; Zhang, Longteng; Lei, Yutian; Shen, Huixing; Yu, Xunpei; Luo, Yongkang
2018-06-15
An iTRAQ-based strategy was applied to investigate proteome changes in mud shrimp during long-term frozen storage under different conditions. A total of 226 proteins was identified as differential abundance proteins (DAPs) in mud shrimp from two frozen treatment groups (-20 °C and -40 °C) compared with the fresh control group. The proteome changes in mud shrimp muscle stored under -20 °C was much greater than that under -40 °C. Correlation analysis between DAPs and quality traits of mud shrimp muscle showed that 12 proteins were correlated closely with color (L ∗ , a ∗ , and b ∗ value) and texture (hardness, elasticity, and chewiness). Bioinformatic analysis revealed that most of these proteins were involved in protein structure, metabolic enzymes, and protein turnover. Among them, several proteins might be potential protein markers for color, and some proteins are good candidate predictors for textural properties of mud shrimp muscle. Copyright © 2018 Elsevier Ltd. All rights reserved.
Pilot-Scale Test of Dephosphorization in Steelmaking Using Red Mud-Based Flux
NASA Astrophysics Data System (ADS)
Li, Fengshan; Zhang, Yanling; Guo, Zhancheng
2017-09-01
Bayer red mud is characterized by its highly oxidizing nature and high alkalinity. It can act as an ideal flux and dephosphorizer in steelmaking. In this study, pilot-scale tests applying the Bayer red mud-based flux in steelmaking have been conducted in a 200-kg, medium-frequency induction furnace. Good slag fluidity and no rephosphorization phenomena are observed. High dephosphorization rates ( 90%) and low final [P] (<0.02%) are obtained in the situation of high [C] of 2.0-3.0%, which are of great importance for the production of clean steel. The P2O5 content in the P-rich phase in the red mud-based slag can reach as high as 34.05 wt.%, far higher than the 6.73 wt.% in ordinary industrial slag. This suggests that the Al2O3, TiO2 in Bayer red mud can enhance the solid solubility of phosphorus in the P-rich phase. The data obtained are important for promoting the large-scale application of red mud in steelmaking.
Ocean dynamics studies. [of current-wave interactions
NASA Technical Reports Server (NTRS)
1974-01-01
Both the theoretical and experimental investigations into current-wave interactions are discussed. The following three problems were studied: (1) the dispersive relation of a random gravity-capillary wave field; (2) the changes of the statistical properties of surface waves under the influence of currents; and (3) the interaction of capillary-gravity with the nonuniform currents. Wave current interaction was measured and the feasibility of using such measurements for remote sensing of surface currents was considered. A laser probe was developed to measure the surface statistics, and the possibility of using current-wave interaction as a means of current measurement was demonstrated.
Hydration kinetics of cementitious materials composed of red mud and coal gangue
NASA Astrophysics Data System (ADS)
Zhang, Na; Li, Hong-xu; Liu, Xiao-ming
2016-10-01
To elucidate the intrinsic reaction mechanism of cementitious materials composed of red mud and coal gangue (RGC), the hydration kinetics of these cementitious materials at 20°C was investigated on the basis of the Krstulović-Dabić model. An isothermal calorimeter was used to characterize the hydration heat evolution. The results show that the hydration of RGC is controlled by the processes of nucleation and crystal growth (NG), interaction at phase boundaries (I), and diffusion (D) in order, and the pozzolanic reactions of slag and compound-activated red mud-coal gangue are mainly controlled by the I process. Slag accelerates the clinker hydration during NG process, whereas the compound-activated red mud-coal gangue retards the hydration of RGC and the time required for I process increases with increasing dosage of red mud-coal gangue in RGC.
2018-06-11
This image from NASA's Mars Reconnaissance Orbiter (MRO) shows a hill with a central crater. Such features have been interpreted as both mud volcanoes (really a sedimentary structure) and as actual volcanoes (the erupting lava kind). They occur on the floor of Valles Marineris below a closed topographic contour that could have held a lake, and the compaction of wet sediments may have created mud volcanoes. The fracture pattern of the bright flow unit surrounding the hill resembles mud cracks. However, there have also been observations from the CRISM instrument interpreted as high-temperature minerals, suggesting actual volcanism, although not necessarily at this location. Fine layers in the hill are consistent with either volcanism or mud flows. Either way, this activity is relatively recent in geologic time and may mark habitable subsurface environments. https://photojournal.jpl.nasa.gov/catalog/PIA22514
NASA Astrophysics Data System (ADS)
Tran, Duc; Kuprenas, Rachel; Strom, Kyle
2018-04-01
Modeling the size and settling velocity of sediment under the influence of flocculation is crucial for the accurate prediction of mud movement and deposition in sediment transport modeling of environments such as agricultural streams, large coastal rivers, estuaries, river plumes, and turbidity currents. Yet, collecting accurate and high resolution data on mud flocs is difficult. As a result, models that account for the influence of flocculation on mud settling velocity are based on sparse data that often present non-congruent relationship in floc properties with basic influencers of flocculations such as suspended sediment concentration. This study examines the influence of suspended sediment concentration on floc size populations within a turbulent suspension. Specifically, the work investigates: (1) the relationship between the equilibrium floc size and suspended sediment concentration under conditions of steady concentration and turbulent shearing; and (2) the speed at which mature flocs adapt to an unsteady drop in the concentration when turbulent shear is constant. Two sets of experiments were used to investigate the target processes. All work was conducted in laboratory mixing tanks using a floc camera and a newly developed image acquisition method. The new method allows for direct imaging and sizing of flocs within turbulent suspensions of clay in concentrations ranging from 15 to 400 mg/L, so that no transfer of the sample to another settling column or imaging tank is needed. The primary conclusions from the two sets of experiments are: (1) that the equilibrium floc size in an energetic turbulent suspension is linearly and positively related to concentration over the range of C = 50 to 400 mg/L, yet with a smaller-than-expected slope based on previous data and models from low-energy environments; and (2) that floc sizes decrease quickly (with a time lag on the order of 1-15 min) to time-varying decreases in concentration at turbulent shearing of G = 50s-1 . Overall the data illustrate that equilibrium floc size is a positive function of concentration, but that the rate of increase is weaker than expected. The data also suggest that approximating the size or settling velocity of some muds with a simple equilibrium model might be appropriate if the time steps of interest are on the order of 10 min or larger. The data also shows the importance of calibrating historic mud settling velocity equations for accurate predictions.
Propellant Mass Gauging: Database of Vehicle Applications and Research and Development Studies
NASA Technical Reports Server (NTRS)
Dodge, Franklin T.
2008-01-01
Gauging the mass of propellants in a tank in low gravity is not a straightforward task because of the uncertainty of the liquid configuration in the tank and the possibility of there being more than one ullage bubble. Several concepts for such a low-gravity gauging system have been proposed, and breadboard or flight-like versions have been tested in normal gravity or even in low gravity, but at present, a flight-proven reliable gauging system is not available. NASA desired a database of the gauging techniques used in current and past vehicles during ascent or under settled conditions, and during short coasting (unpowered) periods, for both cryogenic and storable propellants. Past and current research and development efforts on gauging systems that are believed to be applicable in low-gravity conditions were also desired. This report documents the results of that survey.
History of Artificial Gravity. Chapter 3
NASA Technical Reports Server (NTRS)
Clement, Gilles; Bukley, Angie; Paloski, William
2006-01-01
This chapter reviews the past and current projects on artificial gravity during space missions. The idea of a rotating wheel-like space station providing artificial gravity goes back in the writings of Tsiolkovsky, Noordung, and Wernher von Braun. Its most famous fictional representation is in the film 2001: A Space Odyssey, which also depicts spin-generated artificial gravity aboard a space station and a spaceship bound for Jupiter. The O Neill-type space colony provides another classic illustration of this technique. A more realistic approach to rotating the space station is to provide astronauts with a smaller centrifuge contained within a spacecraft. The astronauts would go into it for a workout, and get their gravity therapeutic dose for a certain period of time, daily or a few times a week. This simpler concept is current being tested during ground-based studies in several laboratories around the world.
Milačič, Radmila; Zuliani, Tea; Ščančar, Janez
2012-06-01
Aluminum (Al) is mostly produced from bauxite ore, which contains up to 70% of Al(2)O(3) (alumina). Before alumina is refined to aluminum metal, it is purified by hot alkaline extraction. As a waste by-product red mud is formed. Due to its high alkalinity and large quantities, it represents a severe disposal problem. In Kidričevo (Slovenia), red mud was washed with water before disposal, and after drying, covered with soil. In Ajka (Hungary), the red mud slurry was collected directly in a containment structure, which burst caused a major accident in October 2010. In the present work the environmental impact of toxic elements in red mud from Kidričevo and Ajka were evaluated by applying a sequential extraction procedure and speciation analysis. The predominant red mud fraction was the insoluble residue; nevertheless, environmental concern was focused on the highly mobile water-soluble fraction of Al and Cr. Al in the water-soluble Ajka mud fraction was present exclusively in form of toxic [Al(OH)(4)](-), while Cr existed in its toxic hexavalent form. Comparative assessment to red mud from Kidričevo (Slovenia) with a lower alkalinity (pH 9) with that from Ajka demonstrated significantly lower Al solubility and the presence of only trace amounts of Cr(VI), confirming that disposal of neutralized mud is environmentally much more acceptable and carries a smaller risk of ecological accidents. Since during the Ajka accident huge amounts of biologically available Al and moderate Cr(VI) concentrations were released into the terrestrial and aquatic environments, monitoring of Al and Cr(VI) set free during remedial actions at the contaminated site is essential. Particular care should be taken to minimize the risk of release of soluble Al species and Cr(VI) into water supplies and surface waters. Copyright © 2012 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mielke, Eckehard W.
Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four-form F and F = dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed.
Support vector machine multiuser receiver for DS-CDMA signals in multipath channels.
Chen, S; Samingan, A K; Hanzo, L
2001-01-01
The problem of constructing an adaptive multiuser detector (MUD) is considered for direct sequence code division multiple access (DS-CDMA) signals transmitted through multipath channels. The emerging learning technique, called support vector machines (SVM), is proposed as a method of obtaining a nonlinear MUD from a relatively small training data block. Computer simulation is used to study this SVM MUD, and the results show that it can closely match the performance of the optimal Bayesian one-shot detector. Comparisons with an adaptive radial basis function (RBF) MUD trained by an unsupervised clustering algorithm are discussed.
Influence of drilling operations on drilling mud gas monitoring during IODP Exp. 338 and 348
NASA Astrophysics Data System (ADS)
Hammerschmidt, Sebastian; Toczko, Sean; Kubo, Yusuke; Wiersberg, Thomas; Fuchida, Shigeshi; Kopf, Achim; Hirose, Takehiro; Saffer, Demian; Tobin, Harold; Expedition 348 Scientists, the
2014-05-01
The history of scientific ocean drilling has developed some new techniques and technologies for drilling science, dynamic positioning being one of the most famous. However, while industry has developed newer tools and techniques, only some of these have been used in scientific ocean drilling. The introduction of riser-drilling, which recirculates the drilling mud and returns to the platform solids and gases from the formation, to the International Ocean Drilling Program (IODP) through the launch of the Japan Agency of Marine Earth-Science and Technology (JAMSTEC) riser-drilling vessel D/V Chikyu, has made some of these techniques available to science. IODP Expedition 319 (NanTroSEIZE Stage 2: riser/riserless observatory) was the first such attempt, and among the tools and techniques used was drilling mud gas analysis. While industry regularly conducts drilling mud gas logging for safety concerns and reservoir evaluation, science is more interested in other components (e.g He, 222Rn) that are beyond the scope of typical mud logging services. Drilling mud gas logging simply examines the gases released into the drilling mud as part of the drilling process; the bit breaks and grinds the formation, releasing any trapped gases. These then circulate within the "closed circuit" mud-flow back to the drilling rig, where a degasser extracts these gases and passes them on to a dedicated mud gas logging unit. The unit contains gas chromatographs, mass spectrometers, spectral analyzers, radon gas analyzers, and a methane carbon isotope analyzer. Data are collected and stored in a database, together with several drilling parameters (rate of penetration, mud density, etc.). This initial attempt was further refined during IODP Expeditions 337 (Deep Coalbed Biosphere off Shimokita), 338 (NanTroSEIZE Stage 3: NanTroSEIZE Plate Boundary Deep Riser 2) and finally 348 (NanTroSEIZE Stage 3: NanTroSEIZE Plate Boundary Deep Riser 3). Although still in its development stage for scientific application, this technique can provide a valuable suite of measurements to complement more traditional IODP shipboard measurements. Here we present unpublished data from IODP Expeditions 338 and 348, penetrating the Nankai Accretionary wedge to 3058.5 meters below seafloor. Increasing mud density decreased degasser efficiency, especially for higher hydrocarbons. Blurring of the relative variations in total gas by depth was observed, and confirmed with comparison to headspace gas concentrations from the cored interval. Theoretically, overpressured zones in the formation can be identified through C2/C3 ratios, but these ratios are highly affected by changing drilling parameters. Proper mud gas evaluations will need to carefully consider the effects of variable drilling parameters when designing experiments and interpreting the data.
Quasilocal conserved charges in a covariant theory of gravity.
Kim, Wontae; Kulkarni, Shailesh; Yi, Sang-Heon
2013-08-23
In any generally covariant theory of gravity, we show the relationship between the linearized asymptotically conserved current and its nonlinear completion through the identically conserved current. Our formulation for conserved charges is based on the Lagrangian description, and so completely covariant. By using this result, we give a prescription to define quasilocal conserved charges in any higher derivative gravity. As applications of our approach, we demonstrate the angular momentum invariance along the radial direction of black holes and reproduce more efficiently the linearized potential on the asymptotic anti-de Sitter space.
Paleocurrents in the Charlie-Gibbs Fracture Zone during the Late Quaternary
NASA Astrophysics Data System (ADS)
Bashirova, L. D.; Dorokhova, E.; Sivkov, V.; Andersen, N.; Kuleshova, L. A.; Matul, A.
2017-12-01
The sedimentary processes prevailing in the Charlie-Gibbs Fracture Zone (CGFZ) are gravity flows. They rework pelagic sediments and contourites, and hereby mask the paleoceanographic information partly. The aim of this work is to study sediments of the AMK-4515 core taken in eastern part of the CGFZ. The sediment core AMK-4515 (52°03.14" N, 29°00.12" W; 370 cm length, water depth 3590 m) is located in the southern valley of the CGFZ. This natural deep corridor is influenced by both the westward Iceland-Scotland Overflow Water and underlying counterflow from the Newfoundland Basin. An alternation of the calcareous silty clays and hemipelagic clayey muds in the studied section indicates similarity between our core and long cores taking from CGFZ. A sharp facies shift was found at 80 cm depth in the investigated core. Only the upper section (0-80 cm) is valid for paleoreconstruction. Planktonic foraminiferal distribution and sea-surface temperature (SST) derived from these allow for tracing the PF and NAC latitudinal migrations during investigated period. So-called sortable silt mean size (SS) was used as proxy for reconstruction of bottom current intensity. The age model is based on δ18O and AMS 14C dating, as well as ice-rafted debris (IRD) counts and CaCO3 content. Stratigraphic subdivision of this section allows to allocate 2 marine isotope stages (MIS) covering the last 27 ka. We refer sediments below this level (80-370 cm) to upper part of turbidite, which was formed as a result of massive slide in the southern channel of the CGFZ. Sandy particles were deposited first, underlying silts and clays. This short-term event occurred so quickly that pelagic sedimentation played no role and was not reflected in the grain size distributions. There is evidence for the significant role of gravity flows in sedimentation in the southern channel of the CGFZ. According to our data, the massive sediment slide occurred in the CGFZ about 27 ka. The authors are grateful to RSF (grant No.14-50-00095) for financial support of analytical studies. Absolute datings were obtained with support from the IKBFU 5-100 Russian academic excellence project.
Molecular Simulation Study on Modification Mechanism of Red Mud Modified Asphalt
NASA Astrophysics Data System (ADS)
Tao, FU; Hui-ming, BAO; xing-xing, Duan
2017-12-01
This article used red mud, the aluminum industrial wastes, as modified asphalt material, through the study of the routine test of modified asphalt properties, and the micro test of electron microscope scanning, infrared spectrum and differential scanning calorimetry analysis etc. to discuss its performance and modification mechanism . The test results show that after mixing red mud, asphalt’s penetration index and 15 °C ductility reduced, softening point enhanced, thus the temperature sensitivity and high temperature stability of asphalt improved; Red mud after mixing the matrix asphalt, can form a uniform, stable and matrix asphalt blending system, and improve the asphalt’s thermal stability. Using molecular simulation technology to analyze the asphalt with the temperature change of energy and find in the process of asphalt melting, the largest is the key to influence on bituminous, and van der waals energy is small. It concludes that red mud -modified asphalt material is mainly controlled by bond energy, in order to obtain its favorable property of modification mechanism, red mud of senior activation and molecular bond energy of asphalt is needed to be enhanced.The results of molecular simulation show that the main component of hematite in red mud is the most adsorbed in the asphalt, the asphaltene is the second, the colloid is the worst, but the adsorption capacity of the colloid is the highest.
Mehryar, Esmaeil; Bi, Jinhua
2016-01-01
To enhance the codigestion of degradation and improve biomethane production potential, sugarcane bagasse and filter mud were pretreated by sodium hydroxide NaOH 1 N at 100°C for 15, 30, and 45 minutes, respectively. Biomethane generation from 1-liter batch reactor was studied at mesophilic temperature (37 ± 1)°C, solid concentrations of 6%, and five levels of mixing proportion with and without pretreatment. The results demonstrate that codigestion of filter mud with bagasse produces more biomethane than fermentation of filter mud as single substrate; even codigested substrate composition presented a better balance of nutrients (C/N ratio of 24.70) when codigestion ratio between filter mud and bagasse was 25 : 75 in comparison to filter mud as single substrate (C/N ratio 9.68). All the pretreatments tested led to solubilization of the organic matter, with a maximum lignin reduction of 86.27% and cumulative yield of biomethane (195.8 mL·gVS−1, digestion of pretreated bagasse as single substrate) obtained after 45 minutes of cooking by NaOH 1 N at 100°C. Under this pretreatment condition, significant increase in cumulative methane yield was observed (126.2 mL·gVS−1) at codigestion ratio of 25 : 75 between filter mud and bagasse by increase of 81.20% from untreated composition. PMID:27738635
Liu, Yanju; Naidu, Ravi; Ming, Hui; Dharmarajan, Rajarathnam; Du, Jianhua
2016-06-01
Extremely large amounts of red mud (bauxite residue) are generated globally every year from alumina refining industries, which are being disposed of on engineered landfills. The objective of this study is to investigate the effects of thermal treatments on red mud for development of utilisation strategies. Thermal treatments of red mud samples and their characterisations were investigated under inert (N2) and oxidative (air) conditions with and without sawdust addition at 200-600°C. After calcination, the resulting samples were analysed using thermogravimetric-infrared spectroscopy (TG-IR) for functional group transformations, thermogravimetric analysis (TGA) for thermal loss profiles and X-ray diffraction (XRD) for mineral transformations. The characterisation results showed that in N2 environment, boehmite in red mud was transferred to transition alumina at around 400°C while losing water from structural components. The addition of sawdust for incubation and calcination of red mud in air increased the surface area, whereas that in nitrogen atmosphere lead to reduction of hematite to magnetite at around 500°C. The incorporated carbon materials played a major role in increasing the surface area especially for pore size less than 2.5 nm. This treated red mud with altered mineral composition and improved properties for binding contaminants can be used for environmental remediation and in the process of metal recovery such as iron. © The Author(s) 2016.
Talha, Zahir; Ding, Weimin; Mehryar, Esmaeil; Hassan, Muhammad; Bi, Jinhua
2016-01-01
To enhance the codigestion of degradation and improve biomethane production potential, sugarcane bagasse and filter mud were pretreated by sodium hydroxide NaOH 1 N at 100°C for 15, 30, and 45 minutes, respectively. Biomethane generation from 1-liter batch reactor was studied at mesophilic temperature (37 ± 1)°C, solid concentrations of 6%, and five levels of mixing proportion with and without pretreatment. The results demonstrate that codigestion of filter mud with bagasse produces more biomethane than fermentation of filter mud as single substrate; even codigested substrate composition presented a better balance of nutrients (C/N ratio of 24.70) when codigestion ratio between filter mud and bagasse was 25 : 75 in comparison to filter mud as single substrate (C/N ratio 9.68). All the pretreatments tested led to solubilization of the organic matter, with a maximum lignin reduction of 86.27% and cumulative yield of biomethane (195.8 mL·gVS -1 , digestion of pretreated bagasse as single substrate) obtained after 45 minutes of cooking by NaOH 1 N at 100°C. Under this pretreatment condition, significant increase in cumulative methane yield was observed (126.2 mL·gVS -1 ) at codigestion ratio of 25 : 75 between filter mud and bagasse by increase of 81.20% from untreated composition.
Experimental Study of Goaf Filling Materials Based on Red Mud
NASA Astrophysics Data System (ADS)
Mu, Mangen; Gao, Xiaozhen; Guo, Taoming; Hu, Xinping
2018-01-01
Red mud as soild waste is difficult to treatment. Goaf filling materials can make a large use of red mud. By the experimental study,we find that the red mud, fly ash, ground slag and desulfida-tion gypsum can be used to make goaf filling materials based on the principle of alkali excitation and metalion stability.Through the control variable method, we find that the optimal proportion of goaf filling materials based on red mud is red mud 55%, fly ash 30%, cement 7.5%, fly ash 2.5%, desulfurization gypsum 5%, admixture 1%, and water solid ratio=1:1.2.The 28days final material strength was 2.0 MPa,which achives the technical specification requirements.Through the test of SEM, XRD and IR, it is indicated that the strength formation of goaf filling material based on red mud is from the unformed linking hydration products of amorphous alkali excitation system. With curing time from 3 to 7 days, the unformed linking hydration products grown a lot of vitreous hydration products. When hydration reaction basicly finished after 28 days, the hydration products have developed into a large volume of massive vitreous with an extremely dense structure. The Ca2SiO3 mineral phase is significantly reduced, which is participate in hydration reactions. The decrease of Ca2SiO3 indicates that the Si-O bond in the system have been ruptured and reorganized.
Automatic mouse ultrasound detector (A-MUD): A new tool for processing rodent vocalizations
Reitschmidt, Doris; Noll, Anton; Balazs, Peter; Penn, Dustin J.
2017-01-01
House mice (Mus musculus) emit complex ultrasonic vocalizations (USVs) during social and sexual interactions, which have features similar to bird song (i.e., they are composed of several different types of syllables, uttered in succession over time to form a pattern of sequences). Manually processing complex vocalization data is time-consuming and potentially subjective, and therefore, we developed an algorithm that automatically detects mouse ultrasonic vocalizations (Automatic Mouse Ultrasound Detector or A-MUD). A-MUD is a script that runs on STx acoustic software (S_TOOLS-STx version 4.2.2), which is free for scientific use. This algorithm improved the efficiency of processing USV files, as it was 4–12 times faster than manual segmentation, depending upon the size of the file. We evaluated A-MUD error rates using manually segmented sound files as a ‘gold standard’ reference, and compared them to a commercially available program. A-MUD had lower error rates than the commercial software, as it detected significantly more correct positives, and fewer false positives and false negatives. The errors generated by A-MUD were mainly false negatives, rather than false positives. This study is the first to systematically compare error rates for automatic ultrasonic vocalization detection methods, and A-MUD and subsequent versions will be made available for the scientific community. PMID:28727808
^4He experiments near T_λ with a heat current and reduced gravity in a low-gravity simulator
NASA Astrophysics Data System (ADS)
Liu, Yuanming; Larson, Melora; Israelsson, Ulf
1998-03-01
Conventional ground-based helium experiments experience limitations due to a variation of the superfluid transition temperature (T_λ) caused by the gravity-induced hydrostatic pressure in a ^4He sample cell. A low-gravity simulator consisting a high field superconducting magnet has been built in our laboratory and the preliminary measurements demonstrated a reduction of gravity in the sample cell. (Melora Larson, Feng-Chuan Liu, and Ulf Israelsson, Czech. J. of Phys. 46, 179 (1996).) We report our latest improvements on the simulator and measurements with a new sample cell which had copper end plates, Vepsel sidewalls, and sidewall probes. The measurements showed that gravity can be canceled with a field-field gradient product of 20.7 T^2/cm (or B=15.5 Tesla), in excellent agreement with the theoretical prediction. The measurements also revealed that the boundary resistance between the thermometers and liquid helium increased from 1.6 cm^2 K/W at zero field to 2.0 cm^2 K/W at B=13.8 Tesla. The preliminary dynamic measurements near T_λ with a heat current and reduced gravity will also be presented. This research was supported by NASA.
Glacimarine Sedimentary Processes and Deposits at Fjord-Terminating Tidewater Glacier Margins
NASA Astrophysics Data System (ADS)
Streuff, K.; O'Cofaigh, C.; Lloyd, J. M.; Noormets, R.; Nielsen, T.; Kuijpers, A.
2016-12-01
Many fjords along Arctic coasts are influenced by tidewater glaciers, some of them fast-flowing ice sheet outlets. Such glaciers provide important links between terrestrial and marine environments, and, due to their susceptibility to climatic and oceanographic changes, have undergone a complex history of advance and retreat since the last glacial maximum (LGM). Although a growing body of evidence has led to a better understanding of the deglacial dynamics of individual glaciers since the LGM, their overall Holocene glacimarine processes and associated sedimentary and geomorphological products often remain poorly understood. This study addresses this through a detailed analysis of sediment cores, swath bathymetric and sub-bottom profiler data collected from seven fjords in Spitsbergen and west Greenland. The sediment cores preserve a complex set of lithofacies, which include laminated and massive muds in ice-proximal, and bioturbated mud in more ice-distal settings, diamicton in iceberg-dominated areas and massive sand occurring as lenses, laminae and thick beds. These facies record the interplay of three main glacimarine processes, suspension settling, iceberg rafting and sediment gravity flows, and collectively emphasise the dominance of glacial meltwater delivery to sedimentation in high Arctic fjords. The seafloor geomorphology in the fjords shows a range of landforms that include glacial lineations associated with fast ice-flow, terminal moraines and debris lobes marking former maximum glacier extents, and small transverse moraines formed during deglaciation by glaciotectonic deformation at the grounding line and crevasse-squeezing. Additional landforms such as iceberg ploughmarks, submarine channels, pockmarks, and debris lobes formed during or after deglaciation by iceberg calving, erosion by meltwater, and sediment reworking. We present here a new model for sedimentary and geomorphological processes in front of contemporary tidewater glaciers, which integrates our findings with those from Alaska, Canada, and east Greenland.
Theoretical model of gravitational perturbation of current collector axisymmetric flow field
NASA Astrophysics Data System (ADS)
Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.
1989-03-01
Some designs of liquid metal collectors in homopolar motors and generators are essentially rotating liquid metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. The role of gravity in modifying this ejection instability is investigated. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical current collector ejection values neglecting gravity effects. The derivation of the mathematical model which determines the perturbation of the liquid metal base flow due to gravitational effects is documented. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector. A rederivation of the hydrodynamic instability threshold of a liquid metal current collector is presented.
Theoretical model of gravitational perturbation of current collector axisymmetric flow field
NASA Astrophysics Data System (ADS)
Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.
1990-05-01
Some designs of liquid-metal current collectors in homopolar motors and generators are essentially rotating liquid-metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. An investigation at David Taylor Research Center is being performed to understand the role of gravity in modifying this ejection instability. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical-current-collector ejection values neglecting gravity effects. The purpose of this paper is to document the derivation of the mathematical model which determines the perturbation of the liquid-metal base flow due to gravitational effects. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid-flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector.
Influence of heterogeneity on second-kind self-similar solutions for viscous gravity currents
Zheng, Zhong; Christov, Ivan C.; Stone, Howard A.
2014-05-01
We report experimental, theoretical and numerical results on the effects of horizontal heterogeneities on the propagation of viscous gravity currents. We use two geometries to highlight these effects: (a) a horizontal channel (or crack) whose gap thickness varies as a power-law function of the streamwise coordinate; (b) a heterogeneous porous medium whose permeability and porosity have power-law variations. We demonstrate that two types of self-similar behaviours emerge as a result of horizontal heterogeneity: (a) a first-kind self-similar solution is found using dimensional analysis (scaling) for viscous gravity currents that propagate away from the origin (a point of zero permeability); (b)more » a second-kind self-similar solution is found using a phase-plane analysis for viscous gravity currents that propagate toward the origin. These theoretical predictions, obtained using the ideas of self-similar intermediate asymptotics, are compared with experimental results and numerical solutions of the governing partial differential equation developed under the lubrication approximation. All three results are found to be in good agreement.« less
Low Reynolds number suspension gravity currents.
Saha, Sandeep; Salin, Dominique; Talon, Laurent
2013-08-01
The extension of a gravity current in a lock-exchange problem, proceeds as square root of time in the viscous-buoyancy phase, where there is a balance between gravitational and viscous forces. In the presence of particles however, this scenario is drastically altered, because sedimentation reduces the motive gravitational force and introduces a finite distance and time at which the gravity current halts. We investigate the spreading of low Reynolds number suspension gravity currents using a novel approach based on the Lattice-Boltzmann (LB) method. The suspension is modeled as a continuous medium with a concentration-dependent viscosity. The settling of particles is simulated using a drift flux function approach that enables us to capture sudden discontinuities in particle concentration that travel as kinematic shock waves. Thereafter a numerical investigation of lock-exchange flows between pure fluids of unequal viscosity, reveals the existence of wall layers which reduce the spreading rate substantially compared to the lubrication theory prediction. In suspension gravity currents, we observe that the settling of particles leads to the formation of two additional fronts: a horizontal front near the top that descends vertically and a sediment layer at the bottom which aggrandises due to deposition of particles. Three phases are identified in the spreading process: the final corresponding to the mutual approach of the two horizontal fronts while the laterally advancing front halts indicating that the suspension current stops even before all the particles have settled. The first two regimes represent a constant and a decreasing spreading rate respectively. Finally we conduct experiments to substantiate the conclusions of our numerical and theoretical investigation.
NASA Astrophysics Data System (ADS)
Thomas, Adam; Holley, Rachel; Burren, Richard; Meikle, Chris; Shilston, David
2010-03-01
The Lampur Sidoarjo mud volcano (Java, Indonesia), colloquially called LUSI, first appeared in May 2006. Its cause, whether the result of natural or anthropogenic activities (or a combination of both), is still being debated within the academic, engineering and political communities.The mud volcano expels up to 150,000 m3 of mud per day; and over time, this large volume of mud has had a major environmental and economic impact on the region. The mud flow from LUSI has now covered 6 km2 to depths some tens of metres, displacing approximately 30,000 residents; and continues to threaten local communities, businesses and industry. With such a large volume of mud being expelled each day it is inevitable (as with onshore oil and gas production fields) that there will be some ground surface movement and instability issues at the mud source (the main vent), and in the vicinity of the mud volcano footprint.Due to the dynamic ground surface conditions, engineers and academics alike have found it difficult to reliably monitor ground surface movements within the effected region using conventional surveying techniques. Consequently, engineers responsible for the risk assessment of ground surface instabilities within the proximity of LUSI have called upon the use of satellite interferometry to continually monitor the hazard.The Advanced Land Observing Satellite (ALOS), launched on 24th January 2006, carries onboard an L- band Synthetic Aperture Radar (SAR) instrument called PALSAR (Phased Array type L-band Synthetic Aperture Radar). In contrast to established C-band (5.6cm wavelength) SAR instruments onboard ERS-1 & -2, Envisat, Radarsat-1, and the recently launched Radarsat-2 satellite, PALSAR's (L-band/23.8cm wavelength) instrument presents a number of advantages, including the ability to map larger-scale ground motions, over relatively short timeframes, in tropical environments, without suffering as significantly from signal decorrelation associated with C-band imagery.This paper presents the results of a 2-year ALOS PALSAR Differential Interferometric (DifSAR) monitoring campaign across the LUSI mud volcano. DifSAR processing was applied to a sequence of images acquired on a 3 to 6-month basis between May 2006 and May 2008. The results highlight the capability of ALOS PALSAR in detecting decimetres of coherent ground subsidence to assist engineers in their analysis of the structure, dynamics and overall stability of the mud volcano and the surrounding region.
Turbulent structures in cylindrical density currents in a rotating frame of reference
NASA Astrophysics Data System (ADS)
Salinas, Jorge S.; Cantero, Mariano I.; Dari, Enzo A.; Bonometti, Thomas
2018-06-01
Gravity currents are flows generated by the action of gravity on fluids with different densities. In some geophysical applications, modeling such flows makes it necessary to account for rotating effects, modifying the dynamics of the flow. While previous works on rotating stratified flows focused on currents of large Coriolis number, the present work focuses on flows with small Coriolis numbers (i.e. moderate-to-large Rossby numbers). In this work, cylindrical rotating gravity currents are investigated by means of highly resolved simulations. A brief analysis of the mean flow evolution to the final state is presented to provide a complete picture of the flow dynamics. The numerical results, showing the well-known oscillatory behavior of the flow (inertial waves) and a final state lens shape (geostrophic adjustment), are in good agreement with experimental observations and theoretical models. The turbulent structures in the flow are visualized and described using, among others, a stereoscopic visualization and videos as supplementary material. In particular, the structure of the lobes and clefts at the front of the current is presented in association to local turbulent structures. In rotating gravity currents, the vortices observed at the lobes front are not of hairpin type but are rather of Kelvin-Helmholtz type.
A comparative study of mud-like and coralliform calcium carbonate gallbladder stones.
Ma, Rui-Hong; Luo, Xiao-Bing; Wang, Xiao-Feng; Qiao, Tie; Huang, Hai-Yi; Zhong, Hai-Qiang
2017-07-01
To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO 3 ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p < .05). The analytic results of FTIR spectroscopy showed that 95.7% (89/93) of the mud-like gallbladder stones were CaCO 3 stones, and mainly aragonite; while all of the coralliform stones were CaCO 3 stones, and mainly calcite (p < .05). Meanwhile, microscopic examination indicated that the detection rate of Clonorchis sinensis eggs in mud-like CaCO 3 stones was lower than that in coralliform CaCO 3 stones (p < .05), and that in aragonite CaCO 3 stones was lower than that in calcite CaCO 3 stones(p < .05). Mud-like CaCO 3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO 3 stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO 3 stones. © 2017 Wiley Periodicals, Inc.
Wave climate, sediment supply and the depth of the sand-mud transition: A global survey
George, D.A.; Hill, P.S.
2008-01-01
The influences of wave climate and sediment supply on the depths of sand-mud transitions (hSMT) are investigated. Depths of sand-mud transitions (SMT) are based on published granulometric data from surface samples gathered from 14 sites in different wave-dominated coastal environments with fluvial input, including high energy (Columbia, Eel, Russian, San Lorenzo, Copper, and Nepean rivers), moderate energy (Ebro, Nile, Santa Clara, Tseng-wen and Kao-ping rivers), and low energy (Po, Pescara and Tronto rivers) regimes. Geometric mean diameter (GMD) and mud percent are compiled from samples along shore-normal transects, and significant correlation is found between these two textural descriptors. Nominally, the SMT is defined as the transition from GMD > 63????m to 25% mud. This dual definition is applied to the 14 systems, and hSMT is tabulated for each system. Correlation is found between hSMT and the depth at which wave-induced bottom shear stress equals the critical erosion shear stress of the largest mud particles and also between hSMT and significant wave height. Lack of correlation between hSMT and sediment load of nearby rivers indicates either that the influence of sediment supply on depth of the sand-mud transition is small or is not adequately represented in this study. Shelf width and slope do not correlate with residuals from a formalized linear relationship between hSMT and significant wave height. The relationship between hSMT and wave climate is useful for calibration of numerical models of erosion and deposition in wave-dominated coastal environments, for prediction of seabed properties in remote or inaccessible areas, and for reconstruction of paleodepth based on facies changes from sand to mud in ancient rocks. ?? 2008.
Szpecht, Dawid; Gorczyńska, Ewa; Kałwak, Krzysztof; Owoc-Lempach, Joanna; Choma, Marta; Styczyński, Jan; Goździk, Jolanta; Dłużniewska, Agnieszka; Wysocki, Mariusz; Kowalczyk, Jerzy R; Chybicka, Alicja; Pieczonka, Anna; Wachowiak, Jacek
2012-06-01
In the study, 48 children with severe acquired aplastic anemia (SAA) transplanted from matched sibling donor (MSD) between 1991 and 2009, and 38 children with SAA transplanted from matched unrelated donor (MUD) between 2000 and 2009 were evaluated. Engraftment was achieved in 45 (93.75 %) patients after MSD-hematopoietic stem cell transplantation (HSCT) and in 33 (86.8 %) after MUD-HSCT. Transplant-related mortality rate after MSD-HSCT was 8 %, while 37 % after MUD-HSCT. After MSD-HSCT 44 (91.7 %) patients are alive for 1-216 months (median: 85 months), while after MUD-HSCT 24 (63.2 %) patients for 1-84 months (median: 16 months). The 5-year probability of event-free survival after MSD-HSCT and MUD-HSCT was 87 and 53 %, respectively, while 5 years of overall survival was 91 and 64 %, respectively. It was concluded that MSD-HSCT as the first line treatment for children with SAA is a safe therapeutic approach with a low rate of treatment failures and excellent outcome. Results of MUD-HSCT in pediatric patients with SAA who failed to respond to immunosuppressive therapy are still inferior than those of MSD-HSCT. Treatment failures of MUD-HSCT are mainly related to infectious complications and graft failure. It seems, however, that HLA-matching of unrelated donors at allelic level along with early MUD-HSCT after FCA (FLUDA, low-dose cyclophosphamide, and anti-thymocyte globulin) conditioning, perhaps using lower Thymoglobulin dose could enable further improvement of long-term results in children with SAA who lack MSD.
The effects of the Yogyakarta earthquake at LUSI mud volcano, Indonesia
NASA Astrophysics Data System (ADS)
Lupi, M.; Saenger, E. H.; Fuchs, F.; Miller, S. A.
2013-12-01
The M6.3 Yogyakarta earthquake shook Central Java on May 27th, 2006. Forty seven hours later, hot mud outburst at the surface near Sidoarjo, approximately 250 km from the earthquake epicentre. The mud eruption continued and originated LUSI, the youngest mud volcanic system on earth. Since the beginning of the eruption, approximately 30,000 people lost their homes and 13 people died due to the mud flooding. The causes that initiated the eruption are still debated and are based on different geological observations. The earthquake-triggering hypothesis is supported by the evidence that at the time of the earthquake ongoing drilling operations experienced a loss of the drilling mud downhole. In addition, the eruption of the mud began only 47 hours after the Yogyakarta earthquake and the mud reached the surface at different locations aligned along the Watukosek fault, a strike-slip fault upon which LUSI resides. Moreover, the Yogyakarta earthquake also affected the volcanic activity of Mt. Semeru, located as far as Lusi from the epicentre of the earthquake. However, the drilling-triggering hypothesis points out that the earthquake was too far from LUSI for inducing relevant stress changes at depth and highlight how upwelling fluids that reached the surface first emerged only 200 m far from the drilling rig that was operative at the time. Hence, was LUSI triggered by the earthquake or by drilling operations? We conducted a seismic wave propagation study on a geological model based on vp, vs, and density values for the different lithologies and seismic profiles of the crust beneath LUSI. Our analysis shows compelling evidence for the effects produced by the passage of seismic waves through the geological formations and highlights the importance of the overall geological structure that focused and reflected incoming seismic energy.
Cellular immune responses and phagocytic activity of fishes exposed to pollution of volcano mud.
Risjani, Yenny; Yunianta; Couteau, Jerome; Minier, Christophe
2014-05-01
Since May 29, 2006, a mud volcano in the Brantas Delta of the Sidoarjo district has emitted mud that has inundated nearby villages. Pollution in this area has been implicated in detrimental effects on fish health. In fishes, leukocyte and phagocytic cells play a vital role in body defenses. We report for the first time the effect of "LUSI" volcano mud on the immune systems of fish in the Brantas Delta. The aim of this study was to find biomarkers to allow the evaluation of the effects of volcanic mud and anthropogenic pollution on fish health in the Brantas Delta. The study took places at the Brantas Delta, which was polluted by volcano mud, and at reference sites in Karangkates and Pasuruan. Leukocyte numbers were determined using a Neubauer hemocytometer and a light microscope. Differential leukocyte counts were determined using blood smears stained with May Grunwald-Giemsa, providing neutrophil, lymphocyte and monocyte counts. Macrophages were taken from fish kidney, and their phagocytic activity was measured. In vitro analyses revealed that leukocyte and differential leukocyte counts (DLC) were higher in Channa striata and Chanos chanos caught from the polluted area. Macrophage numbers were higher in Oreochromis mossambicus than in the other species, indicating that this species is more sensitive to pollution. In areas close to volcanic mud eruption, all specimens had lower phagocytic activity. Our results show that immune cells were changed and phagocytic activity was reduced in the polluted area indicating cytotoxicity and alteration of the innate immune system in fishes exposed to LUSI volcano mud and anthropogenic pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.
Source tracking of prokaryotic communities in fermented grain of Chinese strong-flavor liquor.
Wang, Xueshan; Du, Hai; Xu, Yan
2017-03-06
The fermentation process of Chinese strong-flavor liquor involves numerous microbes originating from Daqu and pit mud. Daqu is the starter of fermentation, and pit mud acts as another source of inoculum of microbes in the liquor-making process. However, the contribution of microbes in pit mud and Daqu to fermented grain, and the sources of microbes in fermented grain are still waiting to be defined clearly. In this study, prokaryotic communities in fermented grain, pit mud and Daqu were identified via next generation sequencing of the V4 region of 16S rRNA gene. Principal-coordinate analysis indicated that Daqu had stronger influence on the prokaryotic communities in fermented grain at the prophase of fermentation, but pit mud influenced the fermented grain continuously during the whole fermentation process. Totally, 299 genera were detected in all fermented grain, pit mud and Daqu samples. Among them, 204 genera were detected in 3days' fermented grain. Ten genera (Lactobacillus, Leuconostoc, Staphylococcus, Gluconobacter, Acetobacter, Petrimonas, Clostridium, Ruminococcus, Methanobacterium and Methanobrevibacter) were dominant, and accounted for 84.31%-87.13% relative abundance of the total prokaryotic community in fermented grain. Venn analysis indicated Daqu was the main source of strict aerobes and facultative aerobes, which took up over 74% of prokaryotic communities in fermented grain. Conversely, pit mud was the sustained-release source of anaerobes, which accounted for over 14% of prokaryotic communities in fermented grain. In addition, part of anaerobes originated from both Daqu and pit mud. This study could help track the source of prokaryotic communities in fermented grain, and improve the quality and controllability in liquor production. Copyright © 2017 Elsevier B.V. All rights reserved.
Liu, Hua; Zeng, Chao; Gao, Shu-guang; Yang, Tuo; Luo, Wei; Li, Yu-sheng; Xiong, Yi-lin; Sun, Jin-peng; Lei, Guang-hua
2013-10-01
A meta-analysis was conducted to examine the effect of mud therapy on pain relief in patients with knee osteoarthritis (OA). A detailed search of PubMed®/MEDLINE® was undertaken to identify randomized controlled trials and prospective comparative studies published before 9 March 2013 that compared mud therapy with control group treatments in patients with knee OA. A quantitative meta-analysis of seven studies (410 patients) was performed. There was a significant difference between the groups in the visual analogue scale pain score (standardized mean difference [SMD] -0.73) and Western Ontario and McMaster Universities Osteoarthritis Index pain score (SMD -0.30), with differences in favour of mud therapy. Mud therapy is a favourable option for pain relief in patients with knee OA. Additional high-quality randomized controlled trials need to be conducted to explore this issue further and to confirm this conclusion.
Radioactivity of peat mud used in therapy.
Karpińska, Maria; Mnich, Krystian; Kapała, Jacek; Bielawska, Agnieszka; Kulesza, Grzegorz; Mnich, Stanisław
2016-02-01
The aim of the study was to determine the contents of natural and artificial isotopes in peat mud and to estimate the radiation dose absorbed via skin in patients during standard peat mud treatment. The analysis included 37 samples collected from 8 spas in Poland. The measurements of isotope concentration activity were conducted with the use of gamma spectrometry methods. The skin dose in a standard peat mud bath therapy is approximately 300 nSv. The effective dose of such therapy is considered to be 22 nSv. The doses absorbed during peat mud therapy are 5 orders of magnitude lower than effective annual dose absorbed from the natural radiation background by a statistical Pole (3.5 mSv). Neither therapeutic nor harmful effect is probable in case of such a small dose of ionising radiation. Copyright © 2015 Elsevier Ltd. All rights reserved.
Red mud application in construction industry: review of benefits and possibilities
NASA Astrophysics Data System (ADS)
Lima, M. S. S.; Thives, L. P.; Haritonovs, V.; Bajars, K.
2017-10-01
Red mud is a waste originated in the processing of bauxite into aluminium, which properties of high alkalinity make it cumulatively stored, occupying increasing deforested areas. Annually, it is estimated that approximately 117 million tons of red mud are generated in the world, with no prospect of use, what represents an imminent risk of pollution prone to contamination. Nevertheless, environmental liabilities caused by red mud affect not only the environment, but also the companies responsible for the waste, which will be subject to highest fee payments. Although there are studies that prove the feasibility of using this solid waste in the constitution of ceramic materials, there are no large-scale applications. This study seeks to evaluate the possibilities of red mud application in construction industry, focusing into two main areas: cement production/ceramic material and road construction. Backgrounds from other researchers were taken into consideration and analysed according environmental, economic and technical feasibilities.
The wister mud pot lineament: Southeastward extension or abandoned strand of the San Andreas fault?
Lynch, D.K.; Hudnut, K.W.
2008-01-01
We present the results of a survey of mud pots in the Wister Unit of the Imperial Wildlife Area. Thirty-three mud pots, pot clusters, or related geothermal vents (hundreds of pots in all) were identified, and most were found to cluster along a northwest-trending line that is more or less coincident with the postulated Sand Hills fault. An extrapolation of the trace of the San Andreas fault southeastward from its accepted terminus north of Bombay Beach very nearly coincides with the mud pot lineament and may represent a surface manifestation of the San Andreas fault southeast of the Salton Sea. Additionally, a recent survey of vents near Mullet Island in the Salton Sea revealed eight areas along a northwest-striking line where gas was bubbling up through the water and in two cases hot mud and water were being violently ejected.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Powell, E.N.; Kendall, J.J. Jr.; Connor, S.J.
1984-09-01
During most offshore drilling operations, drilling muds are routinely discharged into surrounding waters. Because corals are relatively sensitive to many environmental perturbations and can be adversely affected by offshore drilling operations, the effects of drilling muds on corals have received considerable attention. Because drilling muds are discharged intermittently, only periodic exposures of short duration should impact nearby coral reefs. To fully assess the impact of a drilling mud discharge on corals requires an assessment of the capacity for corals to recover from short-term exposure. The purpose of this study was to assess the relative toxicity of a number of mudsmore » that were slated for marine disposal for the coral Acropora cervicornis after a 48-hr recovery period. Calcification rate and free amino acid pool were investigated.« less
Treatment of a mud pit by bioremediation.
Avdalović, Jelena; Đurić, Aleksandra; Miletić, Srdjan; Ilić, Mila; Milić, Jelena; Vrvić, Miroslav M
2016-08-01
The mud generated from oil and natural gas drilling, presents a considerable ecological problem. There are still insufficient remedies for the removal and minimization of these very stable emulsions. Existing technologies that are in use, more or less successfully, treat about 20% of generated waste drilling mud, while the rest is temporarily deposited in so-called mud pits. This study investigated in situ bioremediation of a mud pit. The bioremediation technology used in this case was based on the use of naturally occurring microorganisms, isolated from the contaminated site, which were capable of using the contaminating substances as nutrients. The bioremediation was stimulated through repeated inoculation with a zymogenous microbial consortium, along with mixing, watering and biostimulation. Application of these bioremediation techniques reduced the concentration of total petroleum hydrocarbons from 32.2 to 1.5 g kg(-1) (95% degradation) during six months of treatment. © The Author(s) 2016.
NASA Technical Reports Server (NTRS)
Unuvar, C.; Fredrick, D.; Anselmi-Tamburini, U.; Manerbino, A.; Guigne, J. Y.; Munir, Z. A.; Shaw, B. D.
2004-01-01
Combustion synthesis (CS) generally involves mixing reactants together (e.g., metal powders) and igniting the mixture. Typically, a reaction wave will pass through the sample. In field activated combustion synthesis (FACS), the addition of an electric field has a marked effect on the dynamics of wave propagation and on the nature, composition, and homogeneity of the product as well as capillary flow, mass-transport in porous media, and Marangoni flows, which are influenced by gravity. The objective is to understand the role of an electric field in CS reactions under conditions where gravity-related effects are suppressed or altered. The systems being studied are Ti+Al and Ti+3Al. Two different ignition orientations have been used to observe effects of gravity when one of the reactants becomes molten. This consequentially influences the position and concentration of the electric current, which in turn influences the entire process. Experiments have also been performed in microgravity conditions. This process has been named Microgravity Field Activated Combustion Synthesis (MFACS). Effects of gravity have been demonstrated, where the reaction wave temperature and velocity demonstrate considerable differences besides the changes of combustion mechanisms with the different high currents applied. Also the threshold for the formation of a stable reaction wave is increased under zero gravity conditions. Electric current was also utilized with a chemical oven technique, where inserts of aluminum with minute amounts of tungsten and tantalum were used to allow observation of effects of settling of the higher density solid particles in liquid aluminum at the present temperature profile and wave velocity of the reaction.
NASA Astrophysics Data System (ADS)
Dai, Albert; Wu, Ching-Sen
2018-02-01
High-resolution simulations of unstable cylindrical gravity currents when wandering and splitting motions occur in a rotating system are reported. In this study, our attention is focused on the situation of unstable rotating cylindrical gravity currents when the ratio of Coriolis to inertia forces is larger, namely, 0.5 ≤ C ≤ 2.0, in comparison to the stable ones when C ≤ 0.3 as investigated previously by the authors. The simulations reproduce the major features of the unstable rotating cylindrical gravity currents observed in the laboratory, i.e., vortex-wandering or vortex-splitting following the contraction-relaxation motion, and good agreement is found when compared with the experimental results on the outrush radius of the advancing front and on the number of bulges. Furthermore, the simulations provide energy budget information which could not be attained in the laboratory. After the heavy fluid is released, the heavy fluid collapses and a contraction-relaxation motion is at work for approximately 2-3 revolutions of the system. During the contraction-relaxation motion of the heavy fluid, the unstable rotating cylindrical gravity currents behave similar to the stable ones. Towards the end of the contraction-relaxation motion, the dissipation rate in the system reaches a local minimum and a quasi-geostrophic equilibrium state is reached. After the quasi-geostrophic equilibrium state, vortex-wandering or vortex-splitting may occur depending on the ratio of Coriolis to inertia forces. The vortex-splitting process begins with non-axisymmetric bulges and, as the bulges grow, the kinetic energy increases at the expense of decreasing potential energy in the system. The completion of vortex-splitting is accompanied by a local maximum of dissipation rate and a local maximum of kinetic energy in the system. A striking feature of the unstable rotating cylindrical gravity currents is the persistent upwelling and downwelling motions, which are observed for both the vortex-wandering and vortex-splitting motions and were not previously documented for such flows. Depending on the Reynolds number, the bulges around the circumference of the unstable rotating cylindrical gravity currents may or may not develop into cutoff distinct circulations. The number of bulges is seen to be dependent on the ratio of Coriolis to inertia forces but independent of the Reynolds number for the range of Reynolds number considered in this study.
Dynamics of flexural gravity waves: from sea ice to Hawking radiation and analogue gravity
NASA Astrophysics Data System (ADS)
Das, S.; Sahoo, T.; Meylan, M. H.
2018-01-01
The propagation of flexural gravity waves, routinely used to model wave interaction with sea ice, is studied, including the effect of compression and current. A number of significant and surprising properties are shown to exist. The occurrence of blocking above a critical value of compression is illustrated. This is analogous to propagation of surface gravity waves in the presence of opposing current and light wave propagation in the curved space-time near a black hole, therefore providing a novel system for studying analogue gravity. Between the blocking and buckling limit of the compressive force, the dispersion relation possesses three positive real roots, contrary to an earlier observation of having a single positive real root. Negative energy waves, in which the phase and group velocity point in opposite directions, are also shown to exist. In the presence of an opposing current and certain critical ranges of compressive force, the second blocking point shifts from the positive to the negative branch of the dispersion relation. Such a shift is known as the Hawking effect from the analogous behaviour in the theory of relativity which leads to Hawking radiation. The theory we develop is illustrated with simulations of linear waves in the time domain.
Dynamics of flexural gravity waves: from sea ice to Hawking radiation and analogue gravity.
Das, S; Sahoo, T; Meylan, M H
2018-01-01
The propagation of flexural gravity waves, routinely used to model wave interaction with sea ice, is studied, including the effect of compression and current. A number of significant and surprising properties are shown to exist. The occurrence of blocking above a critical value of compression is illustrated. This is analogous to propagation of surface gravity waves in the presence of opposing current and light wave propagation in the curved space-time near a black hole, therefore providing a novel system for studying analogue gravity. Between the blocking and buckling limit of the compressive force, the dispersion relation possesses three positive real roots, contrary to an earlier observation of having a single positive real root. Negative energy waves, in which the phase and group velocity point in opposite directions, are also shown to exist. In the presence of an opposing current and certain critical ranges of compressive force, the second blocking point shifts from the positive to the negative branch of the dispersion relation. Such a shift is known as the Hawking effect from the analogous behaviour in the theory of relativity which leads to Hawking radiation. The theory we develop is illustrated with simulations of linear waves in the time domain.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roemer, P.; Downhour, R. Jr.
1970-06-30
A drilling mud additive prepared from farinaceous material contains relatively high gluten and fat contents and has between 30 and 40% water soluble solids on a dry basis. The product is particularly useful in rotary drilling as an additive to the drilling mud to inhibit water loss. The key to achieving the desired product is pretreatment of the raw flour and control of moisture. (2 claims)
30 CFR 250.1722 - If I install a subsea protective device, what requirements must I meet?
Code of Federal Regulations, 2010 CFR
2010-07-01
... protective covering, the casing stub or mud line suspension equipment, or the trawl, and a discussion of any... subsea wellheads, casing stubs, mud line suspensions, or other obstructions in water depths less than 300... reveals that a casing stub or mud line suspension is no longer properly protected, or if the trawl does...
THE "MUD VOLCANO," A STINKY THERMAL FEATURE ON THE GRAND ...
THE "MUD VOLCANO," A STINKY THERMAL FEATURE ON THE GRAND LOOP ROAD. ACIDIC HOT SPRINGS HAVE REDUCED THE UNDERLYING LAVA TO A FINE CLAY, PRODUCING AN AREA OF BOILING MUD. THE ODOR OF ROTTEN EGGS IS FROM HYDROGEN SULFIDE GAS. - Grand Loop Road, Forming circuit between Mammoth Hot Springs, Norris Junction, Madison Junction, Old Faithful, Mammoth, Park County, WY
Mud Volcanoes as Exploration Targets on Mars
NASA Technical Reports Server (NTRS)
Allen, Carlton C.; Oehler, Dorothy Z.
2010-01-01
Tens of thousands of high-albedo mounds occur across the southern part of the Acidalia impact basin on Mars. These structures have geologic, physical, mineralogic, and morphologic characteristics consistent with an origin from a sedimentary process similar to terrestrial mud volcanism. The potential for mud volcanism in the Northern Plains of Mars has been recognized for some time, with candidate mud volcanoes reported from Utopia, Isidis, northern Borealis, Scandia, and the Chryse-Acidalia region. We have proposed that the profusion of mounds in Acidalia is a consequence of this basin's unique geologic setting as the depocenter for the tune fraction of sediments delivered by the outflow channels from the highlands.
Bosveld, Floris; Ainslie, Anna; Bellaïche, Yohanns
2017-10-15
Centrosomes nucleate microtubules and are tightly coupled to the bipolar spindle to ensure genome integrity, cell division orientation and centrosome segregation. While the mechanisms of centrosome-dependent microtubule nucleation and bipolar spindle assembly have been the focus of numerous works, less is known about the mechanisms ensuring the centrosome-spindle coupling. The conserved NuMA protein (Mud in Drosophila ) is best known for its role in spindle orientation. Here, we analyzed the role of Mud and two of its interactors, Asp and Dynein, in the regulation of centrosome numbers in Drosophila epithelial cells. We found that Dynein and Mud mainly initiate centrosome-spindle coupling prior to nuclear envelope breakdown (NEB) by promoting correct centrosome positioning or separation, while Asp acts largely independently of Dynein and Mud to maintain centrosome-spindle coupling. Failure in the centrosome-spindle coupling leads to mis-segregation of the two centrosomes into one daughter cell, resulting in cells with supernumerary centrosomes during subsequent divisions. Altogether, we propose that Dynein, Mud and Asp operate sequentially during the cell cycle to ensure efficient centrosome-spindle coupling in mitosis, thereby preventing centrosome mis-segregation to maintain centrosome number. © 2017. Published by The Company of Biologists Ltd.
Liu, Yanju; Naidu, Ravendra; Ming, Hui
2013-03-15
The surface electrochemical properties of red mud (bauxite residue) from different alumina refineries in Australia and China were studied by electrophoresis and measuring surface charge density obtained from acid/base potentiometric titrations. The electrophoretic properties were measured from zeta potentials obtained in the presence of 0.01 and 0.001 M KNO(3) over a wide pH range (3.5-10) by titration. The isoelectric point (IEP) values were found to vary from 6.35 to 8.70 for the red mud samples. Further investigation into the surface charge density of one sample (RRM) by acid/base potentiometric titration showed similar results for pH(PZC) with pH(IEP) obtained from electrokinetic measurements. The pH(IEP) determined from zeta potential measurements can be used as a characteristic property of red mud. The minerals contained in red mud contributed to the different values of pH(IEP) of samples obtained from different refineries. Different relationships of pH(IEP) with Al/Fe and Al/Si ratios (molar basis) were also found for different red mud samples. Copyright © 2012 Elsevier Inc. All rights reserved.
Effects of mud sedimentation on lugworm ecosystem engineering
NASA Astrophysics Data System (ADS)
Montserrat, F.; Suykerbuyk, W.; Al-Busaidi, R.; Bouma, T. J.; van der Wal, D.; Herman, P. M. J.
2011-01-01
Benthic ecosystem engineering organisms attenuate hydrodynamic or biogeochemical stress to ameliorate living conditions. Bioturbating infauna, like the lugworm Arenicola marina, determine intertidal process dynamics by maintaining the sediment oxygenated and sandy. Maintaining the permeability of the surrounding sediment enables them to pump water through the interstitial spaces, greatly increasing the oxygen availability. In a field experiment, both lugworm presence and siltation regime were manipulated to investigate to what extent lugworms are able to cope with sedimentation of increasing mud percentage and how this would affect its ecosystem engineering. Fluorescent tracers were added to experimentally deposited mud to visualise bioturbation effects on fine sediment fractions. Lugworm densities were not affected by an increasing mud percentage in experimentally deposited sediment. Negative effects are expected to occur under deposition with significantly higher mud percentages. Surface chlorophyll a content was a function of experimental mud percentage, with no effect of lugworm bioturbation. Surface roughness and sediment permeability clearly increased by lugworm presence, whereas sediment erosion threshold was not significantly affected by lugworms. The general idea that A. marina removes fine sediment fractions from the bed could not be confirmed. Rather, the main ecosystem engineering effect of A. marina is hydraulic destabilisation of the sediment matrix.
NASA Astrophysics Data System (ADS)
Forsberg, R.; Olesen, A. V.; Barnes, D.; Ingalls, S. E.; Minter, C. F.; Presicci, M. R.
2017-12-01
An accurate coastal geoid model is important for determination of near-shore ocean dynamic topography and currents, as well as for land GPS surveys and global geopotential models. Since many coastal regions across the globe are regions of intense development and coastal protection projects, precise geoid models at cm-level accuracy are essential. The only way to secure cm-geoid accuracies across coastal regions is to acquire more marine gravity data; here airborne gravity is the obvious method of choice due to the uniform accuracy, and the ability to provide a seamless geoid accuracy across the coastline. Current practice for gravity and geoid models, such as EGM2008 and many national projects, is to complement land gravity data with satellite radar altimetry at sea, a procedure which can give large errors in regions close to the coast. To quantify the coastal errors in satellite gravity, we compare results of a large set of recent airborne gravity surveys, acquired across a range of coastal zones globally from polar to equatorial regions, and quantify the errors as a function of distance from the coast line for a number of different global altimetry gravity solutions. We find that accuracy in satellite altimetry solutions depend very much on the availability of gravity data along the coast-near land regions in the underlying reference fields (e.g., EGM2008), with satellite gravity accuracy in the near-shore zone ranging from anywhere between 5 to 20 mGal r.m.s., with occasional large outliers; we also show how these errors may typically propagate into coastal geoid errors of 5-10 cm r.m.s. or more. This highlight the need for airborne (land) gravity surveys to be extended at least 20-30 km offshore, especially for regions of insufficient marine gravity coverage; we give examples of a few such recent surveys and associated marine geoid impacts.
Kazak, Omer; Eker, Yasin Ramazan; Akin, Ilker; Bingol, Haluk; Tor, Ali
2017-10-01
This study reports the eco-friendly preparation of a novel composite material consisting of red mud and carbon spheres, denoted as red mud@C composite, and its application for the removal of 2,4-dichlorophenoxyacetic acid herbicide (2,4-D) from aqueous solution. The preparation route has a green approach because it follows the low-energy consuming one-step hydrothermal process by using starch as a renewable carbon precursor and red mud as a waste from aluminum production industry. Characterization of the red mud@C composite was performed by FT-IR, TGA, SEM, TEM, BET, XRD, and Raman microscopy analyses. The batch adsorption studies revealed that the red mud@C composite has higher 2,4-D adsorption efficiency than those of the red mud and the naked carbon spheres. The maximum removal at initial pH of 3.0 is explained by considering the pKa of 2,4-D and pH of point of zero charge (pH pzc ) of the composite material. The adsorption equilibrium time was 60 min, which followed the pseudo-second-order kinetic model together with intra-particle diffusion model. The isotherm analysis indicated that Freundlich isotherm model better represented the adsorption data, with isotherm parameters of k [15.849 (mg/g) (mg/L) -1/n ] and n (2.985). The prepared composite is reusable at least 5 cycles of adsorption-desorption with no significant decrease in the adsorption capacity.
Dead Sea mud packs for chronic low back pain.
Abu-Shakra, Mahmoud; Mayer, Amit; Friger, Michael; Harari, Marco
2014-09-01
Low back pain (LBP) is chronic disease without a curative therapy. Alternative and complementary therapies are widely used in the management of this condition. To evaluate the efficacy of home application of Dead Sea mud compresses to the back of patients with chronic LBP. Forty-six consecutive patients suffering from chronic LBP were recruited. All patients were followed at the Soroka University Rheumatic Diseases Unit. The patients were randomized into two groups: one group was treated with mineral-rich mud compresses, and the other with mineral-depleted compresses. Mud compresses were applied five times a week for 3 consecutive weeks. The primary outcome was the patient's assessment of the overall back pain severity. The score of the Ronald & Morris questionnaire served as a secondary outcome. Forty-four patients completed the therapy and the follow-up assessments: 32 were treated with real mud packs and 12 used the mineral-depleted packs. A significant decrease in intensity of pain, as described by the patients, was observed only in the treatment group. In this group, clinical improvement was clearly seen at completion of therapy and was sustained a month later. Significant improvement in the scores of the Roland & Morris questionnaire was observed in both groups. The data suggest that pain severity was reduced in patients treated with mineral-rich mud compresses compared with those treated with mineral-depleted compresses. Whether this modest effect is the result of a "true" mud effect or other causes can not be determined in this study.
NASA Astrophysics Data System (ADS)
Benachour, Elhadj; Draoui, Belkacem; Imine, Baachir; Hasnat, Mohammed; Rahmani, Lakhdar
2016-03-01
The thermal behavior of the buildings is a current problem which arouses the interest of many researchers. Indeed, the control of the loads of air conditioning or heating requires a thorough knowledge. Since the thermal quality of the buildings in the Maghreb is there generally very insufficient in particular in the Sahara of Algeria, the insulation proved that it is a very important parameter to minimize the thermal diffusion process inside on all when the insulator is a local material as the Mud which is in our region with a significant amount and almost free quantity. This work presents a study of numerical simulation aiming at the role and the influence of the insulation by the mud Reduced like a local material to the town of Bechar located at the south west of Algeria, or one is interested in a comparative study for pursued these goals. In this context, an analogy was used for the functions which are discretized by the finite difference method and integrated in the Fluent code which is based on the finite volume method. The validation of this procedure was confirmed while comparing some results. The results are presented in the form of distributions of the isotherms, the streamlines, local and average Nusselt of which the goal to study the influence on comfort.
Universality of quantum gravity corrections.
Das, Saurya; Vagenas, Elias C
2008-11-28
We show that the existence of a minimum measurable length and the related generalized uncertainty principle (GUP), predicted by theories of quantum gravity, influence all quantum Hamiltonians. Thus, they predict quantum gravity corrections to various quantum phenomena. We compute such corrections to the Lamb shift, the Landau levels, and the tunneling current in a scanning tunneling microscope. We show that these corrections can be interpreted in two ways: (a) either that they are exceedingly small, beyond the reach of current experiments, or (b) that they predict upper bounds on the quantum gravity parameter in the GUP, compatible with experiments at the electroweak scale. Thus, more accurate measurements in the future should either be able to test these predictions, or further tighten the above bounds and predict an intermediate length scale between the electroweak and the Planck scale.
Cytochalasin D does not inhibit gravitropism in roots
NASA Technical Reports Server (NTRS)
Staves, M. P.; Wayne, R.; Leopold, A. C.
1997-01-01
It is generally thought that sedimenting plastids are responsible for gravity sensing in higher plants. We directly tested the model generated by the current statolith hypothesis that the gravity sensing that leads to gravitropism results from an interaction between the plastids and actin microfilaments. We find that the primary roots of rice, corn, and cress undergo normal gravitropism and growth even when exposed to cytochalasin D, a disruptor of actin microfilaments. These results indicate that an interaction between amyloplasts and the actin cytoskeleton is not critical for gravity sensing in higher plants and weaken the current statolith hypothesis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bohner, Bíborka; Endrődi, Balázs; Tóth, Ágota, E-mail: atoth@chem.u-szeged.hu
The precipitation reaction of calcium oxalate is studied experimentally in the presence of spatial gradients by controlled flow of calcium into oxalate solution. The density difference between the reactants leads to strong convection in the form of a gravity current that drives the spatiotemporal pattern formation. The phase diagram of the system is constructed, the evolving precipitate patterns are analyzed and quantitatively characterized by their diameters and the average height of the gravity flow. The compact structures of calcium oxalate monohydrate produced at low flow rates are replaced by the thermodynamically unstable calcium oxalate dihydrate favored in the presence ofmore » a strong gravity current.« less
30 CFR 250.1721 - If I temporarily abandon a well that I plan to re-enter, what must I do?
Code of Federal Regulations, 2010 CFR
2010-07-01
... or cement plug must be no more than 1,000 feet below the mud line. MMS may consider approving..., or other obstructions that extend above the mud line according to U.S. Coast Guard (USCG) requirements; and (f) Except in water depths greater than 300 feet, protect subsea wellheads, casing stubs, mud...
Lin, Feng-Jiau; Liu, Yuan; Sha, Zhongli; Tsang, Ling Ming; Chu, Ka Hou; Chan, Tin-Yam; Liu, Ruiyu; Cui, Zhaoxia
2012-11-16
The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further evidences for the divergence between the two mud shrimp infraorders, Gebiidea and Axiidea, corroborating previous molecular phylogeny and justifying their infraordinal status. Mitochondrial genome sequences appear to be promising markers for resolving phylogenetic issues concerning decapod crustaceans that warrant further investigations and our present study has also provided further information concerning the mt genome evolution of the Decapoda.
[Situation and assessment of heavy metal pollution in river and mud in one city in Henan Province].
Xi, Jingzhuan; Li, Cuimei; Wang, Shouying; Jiang, Zhigang; Zhang, Miaomiao; Han, Guangliang
2010-11-01
To study the heavy metal contamination status in river water and mud in the suburb of a city in Henan Province. Typical sampling method is used to select a farmland irrigation river of the suburb of a city. Use the atomic absorption spectrophotometry, and measure the heavy metal cadmium (Cd), copper (Cu), lead (Pb) in the river water samples and mud samples by graphite furnace method and flame method, respectively. The results of water were compared with GB 3838-2002, Environmental Quality Standards for Surface Water, and GB 5084-2005, Standards for Irrigation Water Quality. The results of mud were compared with national soil background value. The contents of Cu and Cd in the river samples do not exceed the standard, and that of Pb is 3 to 6 times higher than the standard. According to the single factor pollution index method, the single factor pollution indice of Cu, and Cd in the river are less than 0.2 and are of clean level, while that of Pb reaches 6.84, indicating the Pb pollution in river water is severe. Cu in mud is more than 4 times of the soil background value, and that of Cd is more than 69 times of the soil background value, and that of Pb is more than 2 times of the soil background value. The single item pollution index indicates, in mud, the pollution index of Pb is 2.5, medium level pollution. The pollution indice of Cu and Cd in mud are more than 3, is severe pollution, and the Cd pollution is especially heavy, and the single pollution index reaches 67.76. The comprehensive pollution indice of the river and the mud are 5.346 and 84.115, respectively, indicating that both are at heavy pollution level. The main pollution source of the river originates from Pb, and that of the mud is from Cd and it is required to take measure and control as early as possible.
2012-01-01
Background The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. Results We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Conclusions Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further evidences for the divergence between the two mud shrimp infraorders, Gebiidea and Axiidea, corroborating previous molecular phylogeny and justifying their infraordinal status. Mitochondrial genome sequences appear to be promising markers for resolving phylogenetic issues concerning decapod crustaceans that warrant further investigations and our present study has also provided further information concerning the mt genome evolution of the Decapoda. PMID:23153176
New Views of Earth's Gravity Field from GRACE
NASA Technical Reports Server (NTRS)
2003-01-01
[figure removed for brevity, see original site] [figure removed for brevity, see original site] Map 1Map 2Gravity and the Earth's Shape Gravity is the force that is responsible for the weight of an object and is determined by how the material that makes up the Earth is distributed throughout the Earth. Because gravity changes over the surface of the Earth, the weight of an object changes along with it. One can define standard gravity as the value of gravity for an perfectly smooth 'idealized' Earth, and the gravity 'anomaly' is a measure of how actual gravity deviates from this standard. Gravity reflects the Earth's surface topography to a high degree and is associated with features that most people are familiar with such as large mountains and deep ocean trenches.Progress in Measuring the Earth's Gravity Field Through GRACE Prior to GRACE, the Earth's gravity field was determined using measurements of varying quality from different satellites and of incomplete coverage. Consequently the accuracy and resolution of the gravity field were limited. As is shown in Figure 1, the long wavelength components of the gravity field determined from satellite tracking were limited to a resolution of approximately 700 km. At shorter wavelengths, the errors were too large to be useful. Only broad geophysical features of the Earth's structure could be detected (see map 1).In contrast, GRACE, by itself, has provided accurate gravity information with a resolution of 200 km. Now, much more detail is clearly evident in the Earth's geophysical features (see map 2). High resolution features detected by GRACE that are representative of geophysical phenomena include the Tonga/Kermadec region (a zone where one tectonic plate slides under another), the Himalayan/Tibetan Plateau region (an area of uplift due to colliding plates), and the mid-Atlantic ridge (an active spreading center in the middle of the Atlantic ocean where new crust is being created). Future GRACE gravity models are expected to increase the resolution further. The second figure confirms that the Grace data is global, homogeneous and highly accurate. These are all properties that have been sought for gravity model development. [figure removed for brevity, see original site] Ocean Circulation Measurements from Grace The arrows in the three data sets in Figure 3 depict ocean currents off the East Coast of the United States, 1,000 meters (approximately 3,280 feet) beneath the surface. The top panel is obtained from the GRACE geoid, satellite altimetry and ship measurements of temperature and salt. The bottom panel is computed in the same manner as the top one, except that the best geoid prior to GRACE is used instead of the GRACE geoid. The middle panel shows direct measurement of those currents by floats deployed from ships. Notice that the current arrows in the Gulf Stream extension, East and slightly South of Washington DC, point eastward, toward Europe, in the two upper panels, but in the opposite direction in the lower panel. Colors indicate the strength of the ocean current, with red being strongest and blue-green weakest. Areas in white have no available data.The Gulf Stream region of the North Atlantic is among the best studied in the world's oceans, with a significant quantity of high-quality data available on it as a result of shipborne instrument measurements. In less well studied regions, the new information provided by GRACE, together with satellite altimetry, will increase our knowledge of ocean circulation.NASA Astrophysics Data System (ADS)
Kelly, R. W.; Chalk, C.; Dorrell, R. M.; Peakall, J.; Burns, A. D.; Keevil, G. M.; Thomas, R. E.; Williams, G.
2016-12-01
In the natural environment, gravity currents transport large volumes of sediment great distances and are often considered one of the most important mechanisms for sediment transport in ocean basins. Deposits from many individual submarine gravity currents, turbidites, ultimately form submarine fan systems. These are the largest sedimentary systems on the planet and contain valuable hydrocarbon reserves. Moreover, the impact of these currents on submarine technologies and seafloor infrastructure can be devastating and therefore they are of significant interest to a wide range of industries. Here we present experimental, numerical and theoretical models of time-averaged turbulent shear stresses, i.e. Reynolds stresses. Reynolds stresses can be conceptually parameterised by an eddy viscosity parameter that relates chaotic fluid motion to diffusive type processes. As such, it is a useful parameter for indicating the extent of internal mixing and is used extensively in both numerical and analytical modelling of both open-channel and gravity driven flows. However, a lack of knowledge of the turbulent structure of gravity currents limits many hydro- and morphodynamic models. High resolution 3-dimensional experimental velocity data, gathered using acoustic Doppler profiling velocimetry, enabled direct calculation of stresses and eddy viscosity. Comparison of experimental data to CFD and analytical models allowed the testing of eddy viscosity-based turbulent mixing models. The calculated eddy viscosity profile is parabolic in nature in both the upper and lower shear layers. However, an apparent breakdown in the Boussinesq hypothesis (used to calculate the eddy viscosity and upon which many numerical models are based) is observed in the region of the current around the velocity maximum. With the use of accompanying density data it is suggested that the effect of stratification on eddy viscosity is significant and alternative formulations may be required.
Helium-4 Experiments near T-lambda in a Low-Gravity Simulator
NASA Technical Reports Server (NTRS)
Liu, Yuanming; Larson, Melora; Israelsson, Ulf
2000-01-01
We report our studies of gravity cancellation in a liquid helium sample cell along the lambda-line using a low-gravity simulator facility. The simulator consists of a superconducting magnet capable of producing B(delta-B/delta-z) = 22squareT)/cm. We have verified experimentally that the simulator can cancel gravity to about 0.01g in a cylindrical sample volume of 0.5 cm in diameter and 0.5 cm in height. This allows us to approach more closely the superfluid transition without entering the normal-superfluid two phase region induced by gravity. We also present the measurements of T-c(Q,P): depression of the superfluid transition temperature by a heat current(Q) along the lambda-line (P). The results are consistent with the Renormalization-group theory calculation. Measurements of thermal expansion coefficient in a heat current will also be discussed. The work has been carried out by JPL, California Institute of Technology under contract to NASA.
Multi-scale mass movements: example of the Nile deep-sea fan (NDSF)
NASA Astrophysics Data System (ADS)
Loncke, L.; Droz, L.; Bellaiche, G.; Gaullier, V.; Mascle, J.; Migeon, S.
2003-04-01
The almost 90 000 km2 NDSF, fed by one of the major river in the world, has been nearly entirely surveyed by swath bathymetry and back-scatter imagery during the last four years. Seismic-reflection and 3-5 kHz profiles, and in some places, high resolution data were collected. Some profiles have been provided by BP-Egypt. Using this set of data, we have conducted a multi-scale regional synthesis which stresses the importance of gravity processes in the edification and evolution of this major deep turbidite system. Gravity processes range from regional gravity-driven spreading and gliding of the Plio-Pleistocene sediments above the Messinian mobile evaporites, to huge collapses of large areas of the upper continental slope as well as very localized levee destabilizations and related avulsion mechanisms. The Eastern - tectonized - area of the NDSF is characterized by lens-shaped transparent bodies, likely indicating debris-flow deposits, settled at crestal graben flanks, themselves generated by reactive diapir rise. Debris flows are probably triggered by local readjustments of salt-related tectonic features destabilizing their sedimentary cover. In contrast, within the poorly deformed Western part of the NDSF, we mainly observe recent slumping and gliding phenomenons, incising the upper slope where salt layers are absent. These slumps and glidings evolved downslope to large debris flows. Some of them exhibit volumes up to 1900 km3 and are covered by recent stacked channel-levees units. Smaller scale debris-flows are inter-fingered within these constructional units and led to numerous channel migrations and avulsions, characterized by typical HARP's seismic facies. Recent sedimentary destabilizations seem to be associated with gas seeping or under-compacted mud ascents: in the Central NDSF, the association between pock-marks (or mounds) and destabilizated masses suggest the existence of gas hydrates. Given the variety of processes (either triggered by tectonics, sedimentary overloading, sea-level fluctations, or fluids) and scales of the identified destabilizations, the NDSF appears as an excellent natural laboratory to study mass movement processes.
Improving Realism in Reduced Gravity Simulators
NASA Technical Reports Server (NTRS)
Cowley, Matthew; Harvil, Lauren; Clowers, Kurt; Clark, Timothy; Rajulu, Sudhakar
2010-01-01
Since man was first determined to walk on the moon, simulating the lunar environment became a priority. Providing an accurate reduced gravity environment is crucial for astronaut training and hardware testing. This presentation will follow the development of reduced gravity simulators to a final comparison of environments between the currently used systems. During the Apollo program era, multiple systems were built and tested, with several NASA centers having their own unique device. These systems ranged from marionette-like suspension devices where the subject laid on his side, to pneumatically driven offloading harnesses, to parabolic flights. However, only token comparisons, if any, were made between systems. Parabolic flight allows the entire body to fall at the same rate, giving an excellent simulation of reduced gravity as far as the biomechanics and physical perceptions are concerned. While the effects are accurate, there is limited workspace, limited time, and high cost associated with these tests. With all mechanical offload systems only the parts of the body that are actively offloaded feel any reduced gravity effects. The rest of the body still feels the full effect of gravity. The Partial Gravity System (Pogo) is the current ground-based offload system used to training and testing at the NASA Johnson Space Center. The Pogo is a pneumatic type system that allows for offloaded motion in the z-axis and free movement in the x-axis, but has limited motion in the y-axis. The pneumatic system itself is limited by cylinder stroke length and response time. The Active Response Gravity Offload System (ARGOS) is a next generation groundbased offload system, currently in development, that is based on modern robotic manufacturing lines. This system is projected to provide more z-axis travel and full freedom in both the x and y-axes. Current characterization tests are underway to determine how the ground-based offloading systems perform, how they compare to parabolic flights, and which of the systems is preferable for specific uses. These tests were conducted with six degree of freedom robots and manual inputs. Initial results show a definitive difference in abilities of the two offload systems.
Organic chemical composition of mud from the LUSI mud volcano, Sidoarjo, East Java, Indonesia
NASA Astrophysics Data System (ADS)
Rosenbauer, R. J.; Campbell, P.; Lam, A.
2009-12-01
Sidoarjo, East Java, Indonesia is the site of LUSI, a terrestrial mud volcano that has been erupting since May 29, 2006. In response to a U.S. Department of State request, the U.S. Geological Survey has been assisting the Indonesian Government to describe the geological and geochemical aspects and potential health risk of the mud eruption. We report here on the organic chemical composition of the mud. Organic chemical analyses were carried out by gas chromatography/mass spectroscopy following organic extraction by microwave-assisted solvent extraction and compound fractionation by adsorption chromatography. There is a petroliferous component in the mud that is fresh, immature, and nonbiodegraded. There is a complete suite of n-alkanes with a bell-shaped pattern typical of fresh petroleum with a Cmax around C20. The alkane content ranges from 0.12 to 1.01 mg/kg dry mud. The presence of certain hopanes (i.e. 17 α,21β(H)-30-norhopane and 17α,21β(H)-hopane) is also indicative of the presence of oil. The proportions of other biomarker compounds (pristane/phytane = 2.4) and the dominance of the C27 sterane (5α(H),14α(H),17α(H)-chlolestane) suggest that oil formed under oxic conditions and has a likely coastal marine or terrigenous source. The presence of oleanane indicates a Cretaceous or younger age for the petrogenic material. These geochemical parameters are consistent with Indonesian oil derived from Tertiary marlstone source rocks that contained kerogen deposited under oxic conditions, probably the upper Miocene Klasafet Formation. Polycyclic aromatic hydrocarbons (PAHs) are present and range in content from 0.1 to 2.2 mg/kg dry mud. The low molecular weight (LMW) PAHs, in particular, naphthalene and methyl-naphthalene are dominant except for perylene which is ubiquitous in the environment. The presence of both parent and higher homologue PAHs indicate a petrogenic rather than combustion source. PAHs are known carcinogens but toxicity data in sediments are sparse and often qualitative, depending on the PAH matrix and thus bioavailability. The distribution and content of PAHs measured in the LUSI mud do exceed USEPA recommended interim sediment quality criteria. In addition, judging sediment toxicity on the basis of single PAH compounds risks underestimating effects because mixtures of PAHs tend to aggregate toxicity. Further studies are needed to determine whether or not PAHs are present in levels that exceed soil remediation or aquatic guidelines. The mud contains low levels (tens of ppb) of the higher plant sterols including stigmasterol and β-sitosterol. Also, 22-dehydrocholesterol (generally ascribed to algal material) is present at 39 ppb. These compounds are derived from natural sources, are non-hazardous, and were likely entrained in the mud during ascent to the surface or mixed with the mud post-eruption. The organic compounds identified to date will exhibit a variety of environmental behaviors and effects. Some compounds will volatilize and photo-oxidize or biodegrade relatively quickly (i.e. n-alkanes), and are relatively nontoxic. LMW PAHs are sparingly soluble in water but heavier PAHs will likely persist in the environment and represent potential toxicity to biota because PAHs are bio-accumulative. But the overall toxicity of the mud appears low.
Surface singularities in Eddington-inspired Born-Infeld gravity.
Pani, Paolo; Sotiriou, Thomas P
2012-12-21
Eddington-inspired Born-Infeld gravity was recently proposed as an alternative to general relativity that offers a resolution of spacetime singularities. The theory differs from Einstein's gravity only inside matter due to nondynamical degrees of freedom, and it is compatible with all current observations. We show that the theory is reminiscent of Palatini f(R) gravity and that it shares the same pathologies, such as curvature singularities at the surface of polytropic stars and unacceptable Newtonian limit. This casts serious doubt on its viability.
Erosion properties of cohesive sediments in the Colorado River in Grand Canyon
Akahori, R.; Schmeeckle, M.W.; Topping, D.J.; Melis, T.S.
2008-01-01
Cohesive sediment deposits characterized by a high fraction of mud (silt plus clay) significantly affect the morphology and ecosystem of rivers. Potentially cohesive sediment samples were collected from deposits in the Colorado River in Marble and Grand Canyons. The erosion velocities of these samples were measured in a laboratory flume under varying boundary shear stresses. The non-dimensional boundary shear stress at which erosion commenced showed a systematic deviation from that of non-cohesive sediments at mud fractions greater than 0.2. An empirical relation for the boundary shear stress threshold of erosion as a function of mud fraction was proposed. The mass erosion rate was modelled using the Ariathurai-Partheniades equation. The erosion rate parameter of this equation was found to be a strong function of mud fraction. Under similar boundary shear stress and sediment supply conditions in the Colorado River, cohesive lateral eddy deposits formed of mud fractions in excess of 0.2 will erode less rapidly than non-cohesive deposits. Copyright ?? 2008 John Wiley & Sons, Ltd.
Karpińska, Maria; Kapała, Jacek; Raciborska, Agnieszka; Kulesza, Grzegorz; Milewska, Anna; Mnich, Stanisław
2017-08-01
In this work were identified and measured the activity of radioactive isotopes present in medicinal preparations from peat mud and estimated the doses obtained from them during therapy. Radioactivity of 22 preparations from peat mud and 20 water samples from water of the North-East region of Poland was studied. The median of the total activity was 24.8 Bq kg -1 . Total maximal isotope activity was observed in the Iwonicka Cube 146 Bq kg -1 while considerable amounts of isotopes were found in the Kolobrzeska Peat Mud Paste 112 Bq kg -1 . The doses obtained during therapy were within the range of 11 nSv-13 μSv depending on extracts of medicinal preparations from peat mud. The probability that such a small dose would stimulate biological effects is low. However, some clinicians believe that one of the possible therapeutic mechanisms in the treatment of rheumatoid disorders is the induction of immune response by ionising radiation.
Biostratinomic processes for the development of mud-cast logs in Carboniferous and Holocene swamps
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gastaldo, R.A.; Demko, T.M.; Liu, Yuejin
1989-08-01
Prostrate trees are common features of fossil forest litters, and are frequently preserved as mud-casts. Specimens of Carboniferous mud-cast trees and a mud-filled incipient cast of a Holocene Taxodium have been investigated to determine the biostratinomic processes responsible for their formation. These processes are complex. Hollowing of tree trunks may take place during life or by degradation after death. Once the trunk has fallen, the hollow cavity is supported by surrounding wood and/or bark tissues and acts as a conduit for sediment-laden waters. Leaf litter may be preserved on bedding surfaces. The infilling sequence of horizontal, parallel bedded, fine-grained sedimentmore » is deposited from suspended load during multiple overbank flooding events. These results differ from experimentally produced pith casts in which the sediment grain size is of fine sand. In Holocene specimens, alluvial mud within the log may provide a substrate for infaunal invertebrates. No evidence of infaunal burrowing in Carboniferous analogues exists.« less
NASA Astrophysics Data System (ADS)
Hogg, C. A. R.; Pietrasz, V. B.; Ouellette, N. T.; Koseff, J. R.
2015-12-01
Desalination of seawater offers a source of potable water in arid regions and during drought. However, hypersaline discharge from desalination facilities presents environmental risks, particularly to benthic organisms. The risks posed by salt levels and chemical additives, which can be toxic to local ecosystems, are typically mitigated by ensuring high levels of dilution close to the source. We report on laboratory flume experiments examining how internal waves at the pycnocline of a layered ambient density stratification influence the transport of hypersaline effluent moving as a gravity current down the slope. We found that some of the hypersaline fluid from the gravity current was diverted away from the slope into an intrusion along the pycnocline. A parametric study investigated how varying the energy of the internal wave altered the amount of dense fluid that was diverted into the pycnocline intrusion. The results are compared to an analytical framework that compares the incident energy in the internal wave to potential energy used in diluting the gravity current. These results are significant for desalination effluents because fluid diverted into the intrusion avoids the ecologically sensitive benthic layer and disperses more quickly than if it had continued to propagate along the bed.
Turbulent Mixing in Gravity Currents with Transverse Shear
NASA Astrophysics Data System (ADS)
White, Brian; Helfrich, Karl; Scotti, Alberto
2010-11-01
A parallel flow with horizontal shear and horizontal density gradient undergoes an intensification of the shear by gravitational tilting and stretching, rapidly breaking down into turbulence. Such flows have the potential for substantial mixing in estuaries and the coastal ocean. We present high-resolution numerical results for the mixing efficiency of these flows, which can be viewed as gravity currents with transverse shear, and contrast them with the well-studied case of stably stratified, homogeneous turbulence (uniform vertical density and velocity gradients). For a sheared gravity current, the buoyancy flux, turbulent Reynolds stress, and dissipation are well out of equilibrium. The total kinetic energy first increases as potential energy is transferred to the gravity current, but rapidly decays once turbulence sets in. Despite the non-equilibrium character, mixing efficiencies are slightly higher but qualitatively similar to homogeneous stratified turbulence. Efficiency decreases in the highly energetic regime where the dissipation rate is large compared with viscosity and stratification, ɛ/(νN^2)>100, further declining as turbulence decays and kinetic energy dissipation dominates the buoyancy flux. In general, the mixing rate, parameterized by a turbulent eddy diffusivity, increases with the strength of the transverse shear.
Gravity Field Characterization around Small Bodies
NASA Astrophysics Data System (ADS)
Takahashi, Yu
A small body rendezvous mission requires accurate gravity field characterization for safe, accurate navigation purposes. However, the current techniques of gravity field modeling around small bodies are not achieved to the level of satisfaction. This thesis will address how the process of current gravity field characterization can be made more robust for future small body missions. First we perform the covariance analysis around small bodies via multiple slow flybys. Flyby characterization requires less laborious scheduling than its orbit counterpart, simultaneously reducing the risk of impact into the asteroid's surface. It will be shown that the level of initial characterization that can occur with this approach is no less than the orbit approach. Next, we apply the same technique of gravity field characterization to estimate the spin state of 4179 Touatis, which is a near-Earth asteroid in close to 4:1 resonance with the Earth. The data accumulated from 1992-2008 are processed in a least-squares filter to predict Toutatis' orientation during the 2012 apparition. The center-of-mass offset and the moments of inertia estimated thereof can be used to constrain the internal density distribution within the body. Then, the spin state estimation is developed to a generalized method to estimate the internal density distribution within a small body. The density distribution is estimated from the orbit determination solution of the gravitational coefficients. It will be shown that the surface gravity field reconstructed from the estimated density distribution yields higher accuracy than the conventional gravity field models. Finally, we will investigate two types of relatively unknown gravity fields, namely the interior gravity field and interior spherical Bessel gravity field, in order to investigate how accurately the surface gravity field can be mapped out for proximity operations purposes. It will be shown that these formulations compute the surface gravity field with unprecedented accuracy for a well-chosen set of parametric settings, both regionally and globally.
Mud Volcanoes - A New Class of Sites for Geological and Astrobiological Exploration of Mars
NASA Technical Reports Server (NTRS)
Allen, C.C.; Oehler, D.Z.; Baker, D.M.
2009-01-01
Mud volcanoes provide a unique low-temperature window into the Earth s subsurface - including the deep biosphere - and may prove to be significant sources of atmospheric methane. The identification of analogous features on Mars would provide an important new class of sites for geological and astrobiological exploration. We report new work suggesting that features in Acidalia Planitia are most consistent with their being mud volcanoes.
Recycling of red muds with the extraction of metals and special additions to cement
NASA Astrophysics Data System (ADS)
Zinoveev, D. V.; Diubanov, V. G.; Shutova, A. V.; Ziniaeva, M. V.
2015-01-01
The liquid-phase reduction of iron oxides from red mud is experimentally studied. It is shown that, in addition to a metal, a slag suitable for utilization in the construction industry can be produced as a result of pyrometallurgical processing of red mud. Portland cement is shown to be produced from this slag with mineral additions and a high-aluminate expansion addition to cement.
The biomechanics of burrowing and boring.
Dorgan, Kelly M
2015-01-15
Burrowers and borers are ecosystem engineers that alter their physical environments through bioturbation, bioirrigation and bioerosion. The mechanisms of moving through solid substrata by burrowing or boring depend on the mechanical properties of the medium and the size and morphology of the organism. For burrowing animals, mud differs mechanically from sand; in mud, sediment grains are suspended in an organic matrix that fails by fracture. Macrofauna extend burrows through this elastic mud by fracture. Sand is granular and non-cohesive, enabling grains to more easily move relative to each other, and macrofaunal burrowers use fluidization or plastic rearrangement of grains. In both sand and mud, peristaltic movements apply normal forces and reduce shear. Excavation and localized grain compaction are mechanisms that plastically deform sediments and are effective in both mud and sand, with bulk excavation being used by larger organisms and localized compaction by smaller organisms. Mechanical boring of hard substrata is an extreme form of excavation in which no compaction of burrow walls occurs and grains are abraded with rigid, hard structures. Chemical boring involves secretion to dissolve or soften generally carbonate substrata. Despite substantial differences in the mechanics of the media, similar burrowing behaviors are effective in mud and sand. © 2015. Published by The Company of Biologists Ltd.
Tuffaceous Mud is a Volumetrically Important Volcaniclastic Facies of Reararc Submarine Volcanism
NASA Astrophysics Data System (ADS)
Gill, J. B.; Bongiolo, E.; Miyazaki, T.; Hamelin, C.; Jutzeler, M.
2016-12-01
Unexpectedly, about 2/3 of the 1806 m of rock drilled during IODP Exp 350 on the flank of an Upper Miocene andesitic seamount in the Izu reararc was tuffaceous mud and tuffaceous mudstone that accumulated at high carbonate-free sedimentation rates (60-120 m/MY). This rate is several times faster than at adjacent sites in the forearc or incoming plate. Most tuffaceous muds contain <1% <2 mm-sized fragments of glass shards and plag±cpx crystals. Most muds are dacitic in bulk composition on an anhydrous, carbonate-free basis. They are intercalated with thin ash or tuff beds. The trace element and Sr-Nd-Hf-Pb isotope geochemistry of carbonate-free tuffaceous mud and mudstone indicates that >70% and often >90% of them consist of local volcanic materials that range from basalt to rhyolite. Most exceptions were deposited during Pleistocene glacial intervals. Consequently, tuffaceous mud is an important submarine volcaniclastic facies destined to become shale or slate in the geological record while retaining geochemical information about its provenance. Even though the drill site was <10 km from the summit of a 2-km-high and at times subaerially exposed seamount, and the sedimentation rate exceeded that in the adjacent forearc, tuffaceous mud was the principal reararc volcaniclastic facies. To explain this fine grain size, we infer that much of the submarine volcanism was explosive despite water depths approaching 2 km. The resulting very fine glass quickly becomes clay or is too small to be recognized in thin section or smear slides, and can be sampled only in sediment cores.
WU, LI-TZY; WOODY, GEORGE E.; YANG, CHONGMING; PAN, JENG-JONG; REEVE, BRYCE B.; BLAZER, DAN G.
2012-01-01
While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N=37,897), DSM-IV criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators–multiple causes (MIMIC) approaches. Among 6,917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation=0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups. PMID:22351489
Potential risks of the residue from Samarco's mine dam burst (Bento Rodrigues, Brazil).
Segura, Fabiana Roberta; Nunes, Emilene Arusievicz; Paniz, Fernanda Pollo; Paulelli, Ana Carolina Cavalheiro; Rodrigues, Gabriela Braga; Braga, Gilberto Úbida Leite; Dos Reis Pedreira Filho, Walter; Barbosa, Fernando; Cerchiaro, Giselle; Silva, Fábio Ferreira; Batista, Bruno Lemos
2016-11-01
On November 5th, 2015, Samarco's iron mine dam - called Fundão - spilled 50-60 million m 3 of mud into Gualaxo do Norte, a river that belongs to Rio Doce Basin. Approximately 15 km 2 were flooded along the rivers Gualaxo do Norte, Carmo and Doce, reaching the Atlantic Ocean on November 22nd, 2015. Six days after, our group collected mud, soil and water samples in Bento Rodrigues (Minas Gerais, Brazil), which was the first impacted area. Overall, the results, water samples - potable and surface water from river - presented chemical elements concentration according to Brazilian environmental legislations, except silver concentration in surface water that ranged from 1.5 to 1087 μg L -1 . In addition, water mud-containing presented Fe and Mn concentrations approximately 4-fold higher than the maximum limit for water bodies quality assessment, according to Brazilian laws. Mud particle size ranged from 1 to 200 μm. SEM-EDS spot provided us some semi quantitative data. Leaching/extraction tests suggested that Ba, Pb, As, Sr, Fe, Mn and Al have high potential mobilization from mud to water. Low microbial diversity in mud samples compared to background soil samples. Toxicological bioassays (HepG2 and Allium cepa) indicated potential risks of cytotoxicity and DNA damage in mud and soil samples used in both assays. The present study provides preliminary information aiming to collaborate to the development of future works for monitoring and risk assessment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Surveying a supercoil domain by using the gamma delta resolution system in Salmonella typhimurium.
Higgins, N P; Yang, X; Fu, Q; Roth, J R
1996-01-01
A genetic system was developed to investigate the supercoil structure of bacterial chromosomes. New res-carrying transposons were derived from MudI1734 (MudJr1 and MudJr2) and Tn10 (Tn10dGn). The MudJr1 and MudJr2 elements each have a res site in opposite orientation so that when paired with a Tn10dGn element in the same chromosome, one MudJr res site will be ordered as a direct repeat. Deletion formation was studied in a nonessential region (approximately 100 kb) that extends from the his operon through the cob operon. Strains with a MudJr insertion in the cobT gene at the 5' end of the cob operon plus a Tn10dGn insertion positioned either clockwise or counterclockwise from cobT were exposed to a burst of RES protein. Following a pulse of resolvase expression, deletion formation was monitored by scoring the loss of the Lac+ phenotype or by loss of tetracycline resistance. In exponentially growing populations, deletion products appeared quickly in some cells (in 10 min) but also occurred more than an hour after RES induction. The frequency of deletion (y) diminished with increasing distance (x) between res sites. Results from 15 deletion intervals fit the exponential equation y = 120 . 10(-0.02x). We found that res sites can be plectonemically interwound over long distances ( > 100 kb) and that barriers to supercoil diffusion are placed stochastically within the 43- to 45-min region of the chromosome. PMID:8631670
Tao, Yong; Li, Jiabao; Rui, Junpeng; Xu, Zhancheng; Zhou, Yan; Hu, Xiaohong; Wang, Xiang; Liu, Menghua; Li, Daping; Li, Xiangzhen
2014-04-01
Chinese strong-flavored liquor (CSFL) accounts for more than 70% of all Chinese liquor production. Microbes in pit mud play key roles in the fermentation cellar for the CSFL production. However, microbial diversity, community structure, and cellar-age-related changes in pit mud are poorly understood. Here, we investigated the prokaryotic community structure and diversity in pit-mud samples with different cellar ages (1, 10, 25, and 50 years) using the pyrosequencing technique. Results indicated that prokaryotic diversity increased with cellar age until the age reached 25 years and that prokaryotic community structure changed significantly between three cellar ages (1, 10, and 25 years). Significant correlations between prokaryotic communities and environmental variables (pH, NH4(+), lactic acid, butyric acid, and caproic acid) were observed. Overall, our study results suggested that the long-term brewing operation shapes unique prokaryotic community structure and diversity as well as pit-mud chemistry. We have proposed a three-phase model to characterize the changes of pit-mud prokaryotic communities. (i) Phase I is an initial domestication period. Pit mud is characterized by abundant Lactobacillus and high lactic acid and low pH levels. (ii) Phase II is a transition period. While Lactobacillus abundance decreases dramatically, that of Bacteroidetes and methanogens increases. (iii) Phase III is a relative mature period. The prokaryotic community shows the highest diversity and capability to produce more caproic acid as a precursor for synthesis of ethyl caproate, the main flavor component in CSFL. This research provides scientific evidence to support the practical experience that old fermentation cellars produce high-quality liquor.
Oldale, Robert N.
1989-01-01
Glaciomarine mud in the Gulf of Maine, characterized by rhythmic seismic layers that mimic the morphology of the underlying surface, is composed of subequal amounts of silt and clay, variable amounts of sand, and sparse gravel-sized clasts. The mud is Wisconsinan in age and was deposited during the retreat of the last ice sheet. A beginning date of 38 ka, proposed by King and Fader (1986) in their chronology of the last deglaciation, is considered too old. An alternative chronology, more consistent with the continental record to the west, is proposed here. ln this interpretation, deposition ofglaciomarine mud began about 18 ka when the late Wisconsinan ice retreated from Georges Bank, Great South Channel, and Northeast Channel and ended around 11 ka, when meltwater ceased to enter the Gulf of Maine. Basal-till melt-out from an ice shelf and bergs as the source of the glaciomarine mud, also proposed by King and Fader (1986), is thought to be inconsistent with the volume, widespread rhythmic bedding, and low stone content of the deposit. More likely the source of the glaciomarine mud was rock-flour-laden meltwater that entered the sea along the grounding line of a calving glacier or by way of subaerial meltwater streams. The rock flour was then dispersed by sediment plumes and was deposited when the sediment fell to the sea floor, aided by flocculation and biological agglutination. Rhythmic layers within the glaciomarine mud could represent annual cyclic sedimentation (varves) or cyclic events of lesser duration.
Rotating gravity currents. Part 1. Energy loss theory
NASA Astrophysics Data System (ADS)
Martin, J. R.; Lane-Serff, G. F.
2005-01-01
A comprehensive energy loss theory for gravity currents in rotating rectangular channels is presented. The model is an extension of the non-rotating energy loss theory of Benjamin (J. Fluid Mech. vol. 31, 1968, p. 209) and the steady-state dissipationless theory of rotating gravity currents of Hacker (PhD thesis, 1996). The theory assumes the fluid is inviscid, there is no shear within the current, and the Boussinesq approximation is made. Dissipation is introduced using a simple method. A head loss term is introduced into the Bernoulli equation and it is assumed that the energy loss is uniform across the stream. Conservation of momentum, volume flux and potential vorticity between upstream and downstream locations is then considered. By allowing for energy dissipation, results are obtained for channels of arbitrary depth and width (relative to the current). The results match those from earlier workers in the two limits of (i) zero rotation (but including dissipation) and (ii) zero dissipation (but including rotation). Three types of flow are identified as the effect of rotation increases, characterized in terms of the location of the outcropping interface between the gravity current and the ambient fluid on the channel boundaries. The parameters for transitions between these cases are quantified, as is the detailed behaviour of the flow in all cases. In particular, the speed of the current can be predicted for any given channel depth and width. As the channel depth increases, the predicted Froude number tends to surd 2, as for non-rotating flows.
NASA Astrophysics Data System (ADS)
Görlitz, Marco; Abratis, Michael; Wiersberg, Thomas
2014-05-01
Online monitoring and sampling of drill mud gas (OLGA) was conducted during standard rotary drilling and core drilling of the INFLUINS borehole EF-FB 1/12 to gain information on the composition of gases and their distribution at depth within the Thuringian Syncline (Germany). The method can help to identify areas of enhanced permeability and/or porosity, open fractures, and other strata associated with gases at depth. The gas-loaded drill mud was continuously degassed in a modified gas-water separator, which was installed in the mud ditch in close distance to the drill mud outlet. The extracted gas phase was pumped in a nearby field laboratory for continuous on-line analysis. First information on the gas composition (H2, He, N2, O2, CO2, CH4, Ar, Kr) was available only few minutes after gas extraction. More than 40 gas samples were taken from the gas line during drilling and pumping tests for further laboratory studies. Enhanced concentration of methane, helium, hydrogen and carbon dioxide were detected in drill mud when the drill hole encountered gas-rich strata. Down to a depth of 620 m, the drill mud contained maximum concentration of 55 ppmv He, 1400 ppmv of CH4, 400 ppmv of hydrogen and 1.1 vol-% of CO2. The drilling mud gas composition is linked with the drilled strata. Buntsandstein and Muschelkalk show different formation gas composition and are therefore hydraulically separated. Except for helium, the overall abundance of formation gases in drilling mud is relatively low. We therefore consider the INFLUINS borehole to be dry. The correlation between hydrogen and helium and the relatively high helium abundance rules out any artificial origin of hydrogen and suggest a radiolytic origin of hydrogen. Values CH4/(C2H6/C3H8)
Güngen, Gonca; Ardic, Fusun; Fındıkoğlu, Gülin; Rota, Simin
2012-05-01
The aim of this study was to evaluate the efficacy of treatment with mud pack in knee osteoarthritis (OA) and to determine whether mud pack effects serum levels of YKL-40 and high-sensitivity C-reactive protein (hsCRP) which are reported to be biological markers for articular damage or inflammation in patients with OA. Forty-four patients with the diagnosis of knee OA assigned into two groups were treated with local natural mineral-rich mud pack or hot pack. Treatments were applied for 6 days a week for 2 weeks as a total of 12 sessions. Patients were assessed at baseline, post-treatment, and 3 months after the treatment. VAS, range of motion, 15-m walking time, WOMAC index, Nottingham Health Profile, serum YKL-40, and hsCRP levels were the outcome measures. Pain intensity and joint stiffness decreased in both groups at all follow-ups. Physical activity status was found to persist for 3 months after treatment only in mud pack group. Serum mean YKL-40 and hsCRP levels of the patients were higher compared to healthy control group. Serum YKL-40 level increased significantly only in hot pack group 3 months after the treatment (P < 0.017). No significant change was observed in hsCRP levels in both groups during the whole follow-up periods (P > 0.05). Mud pack and hot pack therapy were both demonstrated to be effective in symptomatic treatment of knee OA until the end of the 2-week treatment period, whereas only mud pack therapy was shown to be effective in functional status over time. In the hot pack group, increased serum YKL-40 level 3 months after the treatment might indicate persistence of cartilage degradation. Maintenance of YKL-40 level in mud pack therapy seems to slow down the progression of knee OA.
Huang, Wen-Shu; Duan, Li-Peng; Huang, Bei; Wang, Ke-Jian; Zhang, Cai-Liang; Jia, Qin-Qin; Nie, Pin; Wang, Tiehui
2016-03-01
The macrophage migration inhibitory factor (MIF) family, consisting of MIF and D-dopachrome tautomerase (DDT) in vertebrates, is evolutionarily ancient and has been found across Kingdoms including vertebrates, invertebrates, plants and bacteria. The mammalian MIF family are chemokines at the top of the inflammatory cascade in combating infections. They also possess enzymatic activities, e.g. DDT catalysis results in the production of 5,6-dihydroxyindole (DHI), a precursor of eumelanin. MIF-like genes are widely distributed, but DDT-like genes have only been described in vertebrates and a nematode. In this report, we cloned a DDT-like gene, for the first time in arthropods, and a second MIF in mud crab. The mud crab MIF family have a three exon/two intron structure as seen in vertebrates. The identification of a DDT-like gene in mud crab and other arthropods suggests that the separation of MIF and DDT preceded the divergence of protostomes and deuterostomes. The MIF family is differentially expressed in tissues of adults and during embryonic development and early life. The high level expression of the MIF family in immune tissues, such as intestine and hepatopancreas, suggests an important role in mud crab innate immunity. Mud crab DDT is highly expressed in early embryos, in megalops and crablets and this coincides with the requirement for melanisation in egg chorion tanning and cuticular hardening in arthropods, suggesting a potential novel role of DDT in melanogenesis via its tautomerase activity to produce DHI in mud crab. The clarification of the presence of both MIF and DDT in this report paves the way for further investigation of their functional roles in immunity and in melanogenesis in mud crab and other arthropods. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Toyos, María H.; Medialdea, Teresa; León, Ricardo; Somoza, Luis; González, Francisco Javier; Meléndez, Nieves
2016-06-01
High-resolution single channel and multichannel seismic reflection profiles and multibeam bathymetric and backscatter data collected during several cruises over the period 1999 to 2007 have enabled characterising not only the seabed morphology but also the subsurface structural elements of the Yuma, Ginsburg, Jesús Baraza and Tasyo mud volcanoes (MVs) in the Gulf of Cádiz at 1,050-1,250 m water depth. These MVs vary strongly in morphology and size. The data reveal elongated cone-shaped edifices, rimmed depressions, and scarps interpreted as flank failures developed by collapse, faulting, compaction and gravitational processes. MV architecture is characterised by both extrusive and intrusive complexes, comprising stacked edifices (including seabed cones and up to four buried bicones) underlain by chaotic vertical zones and downward-tapering cones suggesting feeder systems. These intrusive structures represent the upper layer of the feeder system linking the fluid mud sources with the constructional edifices. The overall architecture is interpreted to be the result of successive events of mud extrusion and outbuilding alternating with periods of dormancy. Each mud extrusion phase is connected with the development of an edifice, represented by a seabed cone or a buried bicone. In all four MVs, the stacked edifices and the intrusive complexes penetrate Late Miocene-Quaternary units and are rooted in the Gulf of Cádiz wedge emplaced during the late Tortonian. Major phases of mud extrusion and outbuilding took place since the Late Pliocene, even though in the Yuma and Jesús Baraza MVs mud volcanism started in the Late Miocene shortly after the emplacement of the Gulf of Cádiz wedge. This study shows that fluid venting in the eastern sector of the Gulf of Cádiz promoted the outbuilding of large long-lived mud volcanoes active since the Late Miocene, and which have been reactivated repeatedly until recent times.
New mud gas monitoring system aboard D/V Chikyu
NASA Astrophysics Data System (ADS)
Kubo, Yusuke; Inagaki, Fumio; Eguchi, Nobuhisa; Igarashi, Chiaki
2013-04-01
Mud gas logging has been commonly used in oil industry and continental scientific drilling to detect mainly hydrocarbon gases from the reservoir formation. Quick analysis of the gas provides almost real-time information which is critical to evaluate the formation and, in particular, safety of drilling operation. Furthermore, mud gas monitoring complements the lack of core or fluid samples particularly in a deep hole, and strengthen interpretations of geophysical logs. In scientific ocean drilling, on the other hand, mud gas monitoring was unavailable in riserless drilling through the history of DSDP and ODP, until riser drilling was first carried out in 2009 by D/V Chikyu. In IODP Exp 319, GFZ installed the same system with that used in continental drilling aboard Chikyu. High methane concentrations are clearly correlated with increased wood content in the cuttings. The system installation was, however, temporary and gas separator was moved during the expedition for a technical reason. In 2011, new mud gas monitoring system was installed aboard Chikyu and was used for the first time in Exp 337. The gas separator was placed on a newly branched bypass mud flow line, and the gas sample was sent to analysis unit equipped with methane carbon isotope analyzer in addition to mass spectrometer and gas chromatograph. The data from the analytical instruments is converted to depth profiles by calculating the lag effects due to mud circulation. Exp 337 was carried out from July 26 to Sep 30, 2011, at offshore Shimokita peninsula, northeast Japan, targeting deep sub-seafloor biosphere in and around coal bed. Data from the hole C0020A, which was drilled to 2466 mbsf with riser drilling, provided insights into bio-geochemical process through the depth of the hole. In this presentation, we show the design of Chikyu's new mud gas monitoring system, with preliminary data from Exp 337.
Genesis of mud volcano fluids in the Gulf of Cadiz - A novel model approach
NASA Astrophysics Data System (ADS)
Schmidt, Christopher; Burwicz, Ewa; Hensen, Christian; Martínez-Loriente, Sara; Wallmann, Klaus; Gràcia, Eulàlia
2017-04-01
Mud volcanism and fluid seepage are common phenomena on the continental margin in the Gulf of Cadiz, North East Atlantic Ocean. Over the past 2 decades more than 50 mud volcanoes have been discovered and investigated interdisciplinarily. Mud volcano fluids emanating at these sites are sourced at great depths and migration is often mediated by strike slip faults in a seismically active region. The geochemical signals of the mud volcano fluids are affected by widespread various processes such as clay mineral dehydration, but also the recrystallization of ancient carbonate rocks and the alteration of oceanic crust have been suggested (Hensen et al., 2015). We developed a novel fully-coupled, basin-scale, reaction-transport model with an adaptive numerical mesh to simulate the fluid genesis in this region. An advantage of this model is the coupling of a realistic geophysical and geochemical approach, considering a growing sediment column over time together with instant compaction of sediments as well as diffusion and advection of dissolved pore water species and chemical reactions. In this proof of concept study, we looked at various scenarios to identify the processes of fluid genesis for 4 mud volcanoes, representing combinations in different subsurface settings. We can reproduce the fluid signatures (chloride, strontium, 87Sr/86Sr) of all mud volcanoes. Furthermore, we can give additional evidence that alteration of oceanic crust by fluid flow is a likely process affecting the fluid composition. Hensen, C., Scholz, F., Nuzzo, M., Valadares, V., Gràcia, E., Terrinha, P., Liebetrau, V., Kaul, N., Silva, S., Martínez-Loriente, S., Bartolome, R., Piñero, E., Magalhães, V. H., Schmidt, M., Weise, S. M., Cunha, M., Hilario, A., Perea, H., Rovelli, L., and Lackschewitz, K., 2015, Strike-slip faults mediate the rise of crustal-derived fluids and mud volcanism in the deep sea: Geology, v. 43, no. 4, p. 339-342.
Chenier Development within a Prograding Strandplain Complex
NASA Astrophysics Data System (ADS)
FitzGerald, D.; Hein, C. J.; Georgiou, I. Y.
2017-12-01
Strandplains dominate the southern coast of Brazil due to abundant shelf and local sediment and falling sea-level (2-4 m) during the past 6 ka. These plains are composed chiefly of swash-aligned sandy beach and dune ridges deposited in bedrock-framed embayments 2-5 km wide and 3-10 km long. The Tijucas Strandplain developed in a more sheltered and deeply embayed setting fronted by long peninsulas and bedrock islands, which reduce ocean wave energy. The Tijucas River bisects the plain and has provided the primary source of sediment to produce a Holocene basinal fill composed of a seaward-thickening bay mud sequence (10-16 m thick). Long-term gradual shoaling of the basin and attendant lessening wave energy produced upper strandplain foreshore and beach units that transition from landward 8-m thick sand sections to a 3-4-m thick mud unit along the present-day shoreline. The gradual lateral change of the morpho-sedimentary character of the plain is likely a product of climate-induced changes in sediment composition and supply and/or wave regime. For example, the mid-plain is defined by a series of abrupt alterations between sand-dominated beach ridges and mixed sand-and-mud cheniers. This area contains at least four chenier complexes consisting of closely spaced (25-40 m apart) 50-75 m wide ridges composed of 3-4 m thick shelly sand underlain and separated by a cohesive basin-fill clay. The seaward portion of the plain has two sandy chenier ridges each 1 m high and <3 m thick, separated by 100 m of consolidated mud with rare sand beds. Ground-penetrating radar sections show ridges contain numerous seaward-sloping beds having variable dips and multiple truncations, resulting from repeated erosional and depositional events. Expansive, thin (<50 cm) sand sheets composed of flat-lying to shallowly landward-dipping internal radar reflections extend landward from most chenier ridges that overtop inter-ridge mud. The present beach comprises the most current developing chenier. Recent storm-induced landward transport of a thin, sandy overwash fan mimics the proposed mechanism for earlier ridge-swale development. Finally, a future chenier is forming 1 km offshore where breaking waves concentrate sand. Between these two sand deposits is a shallow (< 3 m) muddy region where cores and surface samples indicate an absence of sand.
Submarine glaciated landscapes of central and northern British Columbia, Canada
NASA Astrophysics Data System (ADS)
Shaw, John; Lintern, Gwyn
2015-04-01
Recent systematic multibeam sonar mapping and ground-truthing surveys in the fjords and coastal waters of central and northern British Columbia, Canada, provide information on glacial processes associated with the Cordilleran Ice Sheet, and also on postglacial processes that have strongly modified the glacial terrain. During the last glacial maximum, ice covered the Coast Range, except for nunataks. Convergent streamlined glacial landforms in the Strait of Georgia testify to a strong flow of ice towards the southeast, between Vancouver Island and the mainland. During ice retreat, thick deposits of acoustically stratified glaciomarine mud were deposited in glacially over deepened basins. Retreat through the Douglas Channel fjord system was punctuated by still stands, resulting in a series of submarine moraines. Postglacial processes have created a suite of landforms that mask the primary glacial terrain: 1) Fjord floors host thick deposits of acoustically transparent postglacial mud with highly variable distribution: banks up to 80-m thick are commonly adjacent to erosional zones with glaciomarine mud exposed at the seafloor; 2) In this region of high precipitation and snowpack melt, numerous cone-shaped Holocene fan deltas developed on the fjord sidewalls transport coarse sediment to the fjord floors. Larger deltas are developed at fjord heads, notably at Kitimat and Kildala; 3) Submarine slope failures in this tectonically active area have resulted in a suite of mass transport deposits on sidewalls and fjord floors. The very large submarine slope failures at Camano Sound and KitKat Inlet occurred on the steep, rear facets of large transverse moraines, and involved the failure of glaciomarine sediment that moved into deeper basins, perhaps as a retrogressive failure. The ages of these events are unknown, although the presence of postglacial mud in the slide scar at Caamano suggests that the event at that location occurred in the late glacial or early Holocene. Also, sub-bottom profiling shows that some mass transport deposits apparent on the multibeam imagery are not recent, and are blanketed by postglacial mud. Thus, submarine slope failure has been occurring throughout postglacial time; 4) Large, detached bedrock blocks on the fjord sidewall are currently being investigated with a view to understanding their rates of movement. They are provisionally interpreted as creep features, similar to terrestrial sackung.
NASA Astrophysics Data System (ADS)
Perry, C. T.; Beavington-Penney, S. J.
2005-02-01
Seagrass beds have been widely recognised as playing an important role in influencing carbonate sediment facies development. This reflects their role not only as facilitators of fine sediment settling and stabilisation, but also as substrates for epiphytic organisms that, after death, contribute skeletal carbonate to the sediment substrate. In low latitude (reef-related) settings, epiphytic carbonate production rates are often high and this, in combination with the trapping of carbonate mud produced by a range of associated calcareous algal species, typically results in the development of carbonate mud-rich facies. Whilst such environments, and their associated sediment substrates, have been widely documented, studies of seagrass facies in marginal (sub-tropical/warm temperate) marine settings have not been conducted from a sedimentological perspective. This study determines rates of epiphytic carbonate production on two seagrass species Thalassodendron ciliatum and Thalassia hemprichii, and examines seagrass sediment facies from a sub-tropical reef-related environment in southern Mozambique. Dense seagrass beds colonise primarily siliciclastic sediment substrates and are characterised by low rates of epiphytic carbonate production (mean: 43.9 g CaCO 3 m -2 year -1 for T. ciliatum, and 33.4 g CaCO 3 m -2 year -1 for T. hemprichii). Epiphytic encrusters are dominated by thin, monostromatic layers of the crustose coralline red algae Hydrolithon farinosum, along with rotaliid smaller benthic foraminifera (including Asterorotalia cf. gaimardi and Spirillina sp.) and the soritid Peneroplis sp., as well as rare encrusting acervulinid foraminifera, serpulids and bryozoans. Epiphytic calcium carbonate production rates are therefore low and this is reflected in the low (<15%) carbonate content of the seagrass sediments, as well as the low (<1%) sediment fine (<63 μm size fraction) content. This study suggests that mud-rich sediment facies do not necessarily develop in conjunction with seagrass beds and that mud-poor facies may develop in some seagrass-colonised environments. At these sites (sub-tropical and siliciclastic-sediment dominated) this is suggested to reflect both the low levels of epiphytic and benthic algal carbonate mud production as well as a net outflux of fine-grained sediment due to tidal current-induced sediment resuspension. In keeping with carbonate facies generally there are thus likely to be latitude and environment-related shifts in the composition and character of seagrass related sediment facies.
Gravity Perception in a Cladoceran-zooplankter: Anatomy of Antennal Socket Setae of Daphnia Magna
NASA Technical Reports Server (NTRS)
Meyers, D. G.
1985-01-01
Night orientation in Daphnia magna was recently associated with setae on the basal socket of the swimming antennae. Daphnids are suspected of maintaining nocturnal equilibrium by monitoring the gravity vector through upward setal deflections caused by sinking between antennal swimming strokes. Setae appear to be hydrodynamic rheoceptors that sense the gravity vector indirectly by mechanoreceptivity to the direction and velocity of water currents. Neuroanatomical stains have revealed cell bodies at the base of the setal shafts, dendritic connections through to the distal ends of the shafts, and axonal tracts around the antennal socket connecting with an additional cell body and continuing toward the brain. These anatomical observations combined with previous scanning electron microscopy studies suggest that the setae are similar to mechanoreceptors and propreceptors used by higher crustaceans to sense water currents and gravity, and maintained balance.
A seismic reflection velocity study of a Mississippian mud-mound in the Illinois basin
NASA Astrophysics Data System (ADS)
Ranaweera, Chamila Kumari
Two mud-mounds have been reported in the Ullin limestone near, but not in, the Aden oil field in Hamilton County, Illinois. One mud-mound is in the Broughton oil field of Hamilton County 25 miles to the south of Aden. The second mud-mound is in the Johnsonville oil field in Wayne County 20 miles to the north of Aden. Seismic reflection profiles were shot in 2012 adjacent to the Aden oil field to evaluate the oil prospects and to investigate the possibility of detecting Mississippian mud-mounds near the Aden field. A feature on one of the seismic profiles was interpreted to be a mud-mound or carbonate buildup. A well drilled at the location of this interpreted structure provided digital geophysical logs and geological logs used to refine the interpretation of the seismic profiles. Geological data from the new well at Aden, in the form of drill cuttings, have been used to essentially confirm the existence of a mud-mound in the Ullin limestone at a depth of 4300 feet. Geophysical well logs from the new well near Aden were used to create 1-D computer models and synthetic seismograms for comparison to the seismic data. The reflection seismic method is widely used to aid interpreting subsurface geology. Processing seismic data is an important step in the method as a properly processed seismic section can give a better image of the subsurface geology whereas a poorly processed section could mislead the interpretation. Seismic reflections will be more accurately depicted with careful determination of seismic velocities and by carefully choosing the processing steps and parameters. Various data processing steps have been applied and parameters refined to produce improved stacked seismic records. The resulting seismic records from the Aden field area indicate a seismic response similar to what is expected from a carbonate mud-mound. One-dimensional synthetic seismograms were created using the available sonic and density logs from the well drilled near the Aden seismic lines. The 1-D synthetics were used by Cory Cantrell of Royal Drilling and Producing Company to identify various reflections on the seismic records. Seismic data was compared with the modeled synthetic seismograms to identify what appears to be a carbonate mud-mound within the Aden study area. No mud-mounds have been previously found in the Aden oil field. Average and interval velocities obtained from the geophysical logs from the wells drilled in the Aden area was compared with the same type of well velocities from the Broughton known mud-mound area to observe the significance of velocity variation related to the un-known mud-mound in the Aden study area. The results of the velocity study shows a similar trends in the wells from both areas and are higher at the bottom of the wells. Another approach was used to observe the variation of root mean square velocities calculated from the sonic log from the well velocity from the Aden area and the stacking velocities obtained from the seismic data adjacent to the well.
Morphodynamic rotation of an embayed sandy beach in a mud-dominated setting
NASA Astrophysics Data System (ADS)
Brunier, Guillaume; Anthony, Edward; Gardel, Antoine; Millet, Bertrand; Fleury, Jules; Dussouillez, Philippe
2016-04-01
The morphodynamics of beaches between bedrock headlands along the muddy French Guiana coast in South America are controlled by rotation induced by the alongshore migration of mud banks from the mouths of the Amazon River. As they migrate alongshore, these mud banks generate changes in shore-incident wave angles, resulting in reversals in longshore drift. A poor appreciation of the problems caused by this process has resulted in the past in damages to the highly urbanized sea-fronts on these beaches, including erosion and flooding. This work enhances our understanding of this rather unusual type of mud-induced rotation based on surveys of the 4 km-long Montjoly beach near Cayenne, in French Guiana, in the course of an approaching mud bank between October 2013 and October 2014. Our method was based on innovative high-resolution topographic surveys from airborne Structure-from-Motion (SfM) photogrammetry over the beach in October 2013, March 2014 and October 2014. We produced digital surface models (DSM) with a resolution of 10 cm/pixel and an accuracy less than 10 cm from RTK-GPS measurements. We further measured incident wave heights from pressure sensors and conducted a bathymetric survey of the nearshore zone in October 2014. We also modelled high-tide wave propagation over the bathymetry using the REF/DIF v2.5 model. The results show the transfer of sand from the northern part of beach to the south between October 2013 and March 2014. The October 2013 DSM shows a reflective beach in the north indicative of erosion, with a narrow 50 m-wide upper beach. The southern sector was smoother and up to 90 m-wide. Between October 2013 and March 2014, the beach rotated under the influence of a mud bank, with a 30-m retreat of the berm in the north and an advance of 40 m in the south. We quantified a loss of ≈66,000 m³ of sand in the north and a gain of ≈22,000 m³ in the south over this six-month period. The October 2014 DSM shows minor morphological changes, thus indicating the end of the rotation around March 2014 and the beginning of a phase of nearshore mud-bounding of the beach as the mud bank migrated westward. The bathymetric survey showed a 2 m-high and 100 m-wide mud bar in the nearshore zone that dissipated wave energy. Hydrodynamic monitoring between March and October 2014 confirmed this low wave-energy regime (Hs < 0.5 m) compared to a more energetic regime in the neighbouring Montabo Bay beach (Hs up to 1.5 m) located downdrift of the mud bank. The REF/DIF model confirmed the strong wave energy dissipation over the mud bar. Our study highlights the rapidity and intensity of the morphodynamic changes these beaches can undergo in a muddy context, and the need for continuous and accurate monitoring in order to assess the erosion hazard caused by rotation. Keywords: Beach rotation; Mud banks; aerial SFM photogrammetry; bathymetric monitoring; hydrodynamic modelling; REF/DIF model.
Alpha-Particle Gas-Pressure Sensor
NASA Technical Reports Server (NTRS)
Buehler, M. C.; Bell, L. D.; Hecht, M. H.
1996-01-01
An approximate model was developed to establish design curves for the saturation region and a more complete model developed to characterize the current-voltage curves for an alpha-particle pressure sensor. A simple two-parameter current-voltage expression was developed to describe the dependence of the ion current on pressure. The parameters are the saturation-current pressure coefficient and mu/D, the ion mobility/diffusion coefficient. The sensor is useful in the pressure range between 0.1 and 1000 mb using a 1 - mu Ci(241) Am source. Experimental results, taken between 1 and up to 200 mb, show the sensor operates with an anode voltage of 5 V and a sensitivity of 20 fA/mb in nitrogen.
IODP Expedition 366 Reveals Widespread Seamount Subduction Effects in the Mariana Forearc
NASA Astrophysics Data System (ADS)
Fryer, P. B.; Wheat, C. G.; Williams, T.
2017-12-01
Numerous studies of the subduction of seamounts at accretionary convergent plate margins show considerable vertical tectonic deformation in the forearc region. This includes embayment of the trench axis, steepening of the inner trench slope, the creation of troughs in the wake of the seamount track beneath the forearc sediment wedge, but hypotheses regarding the seismogenic consequences of these processes are frequently at odds. In the nonaccretionary Mariana convergent plate margin, it is clear that ridges crosscut the entire forearc region in commensurate dimensions with thicker areas of subducting Pacific plate. Furthermore, to-date deep-sea drilling results on ODP Legs 125 and 195 and on IODP Expedition 366 recovered seamount materials from 5 serpentinite mud volcanoes over a 640 km along-strike distance, within 90 km west of the trench axis, and from 13 to 19 km depth to slab. The location of the serpentinite mud volcanoes is always associated with fault lineaments. The faulting creates the conduits for eruption of mixtures of fluids from the subduction channel and fault gouge from both the subduction channel and the forearc lithosphere. Cores from IODP 366 confirm that seamount subduction and deformation is a temporally and spatially pervasive process on the Mariana forearc. The new findings provide windows on a continuum of the evolution of plate and seamount subduction from the trench to nearly 20 km depth within the subduction channel. Cased boreholes were deployed at the summits of three active serpentinite mud volcanoes (Yinazao (Blue Moon), Asùt Tesoro (Big Blue), and Fantangisña (Celestial) Seamounts) during Expedition 366. These, plus the existing borehole observatory at ODP Site 1200C on the active summit of Conical Seamount provide a means to monitor processes of subduction related to serpentinite mud volcanism of the Mariana forearc. Such drilling results and borehole observations impact current paradigms of lithospheric deformation, mass cycling, and physical conditions within the subduction channel.
NASA Astrophysics Data System (ADS)
Wang, Shuhong; Zhang, Nan; Chen, Han; Li, Liang; Yan, Wen
2014-10-01
The grain size as well as some major and trace elements, including rare earth element (REE), for 273 surface sediment samples collected from the continental shelf of the northern South China Sea were analyzed in this study. The sediment types are mainly sandy silt and silt, making up 60% of the whole samples, and secondly are mud, sandy mud, muddy sand and silty sand, making up 28% of the whole samples, based on grain-size in which the Folk's classification was used. The total REE content (ΣREE) show a wide variation from 21 ppm to 244 ppm with an average value of 155 ppm, which similar to the average ΣREE of the China loess, but much different from that in deep-sea clay, showing a significant terrigenous succession. The REE contents in different sediment types vary greatly, mainly enriching in silt, sandy silt, mud and sandy mud. The REE distribution contours parallel to the coastal, presenting like strips and their contents gradually reduce with increasing distance from the coast. The high content of the western Pearl River Mouth, Shang/Xiachuan Islands and Hailing Bay might be regarded to the coastal current developed from the east to the west along to the Pearl River Mouth in the northern South China Sea. But the chondrite-normalized REE patterns in various sediment types have no difference, basically same as those of coastal rivers and upper crust. They all show relative enrichments in light rare earth element (LREE), noticeable negative Eu anomaly and no Ce anomaly, indicating that those sediments are terrigenous sediments and from the same source region. Further analysis suggest that the sedimentary environment in the study area is relatively stable and granite widely distributed in the South China mainland is the main source of REE, which are transported mainly by the Pearl River. The late diagenesis has little effect on the REE.
Combustion and fires in low gravity
NASA Technical Reports Server (NTRS)
Friedman, Robert
1994-01-01
Fire safety always receives priority attention in NASA mission designs and operations, with emphasis on fire prevention and material acceptance standards. Recently, interest in spacecraft fire-safety research and development has increased because improved understanding of the significant differences between low-gravity and normal-gravity combustion suggests that present fire-safety techniques may be inadequate or, at best, non-optimal; and the complex and permanent orbital operations in Space Station Freedom demand a higher level of safety standards and practices. This presentation outlines current practices and problems in fire prevention and detection for spacecraft, specifically the Space Station Freedom's fire protection. Also addressed are current practices and problems in fire extinguishment for spacecraft.
Flow-driven pattern formation in the calcium-oxalate system.
Bohner, Bíborka; Endrődi, Balázs; Horváth, Dezső; Tóth, Ágota
2016-04-28
The precipitation reaction of calcium oxalate is studied experimentally in the presence of spatial gradients by controlled flow of calcium into oxalate solution. The density difference between the reactants leads to strong convection in the form of a gravity current that drives the spatiotemporal pattern formation. The phase diagram of the system is constructed, the evolving precipitate patterns are analyzed and quantitatively characterized by their diameters and the average height of the gravity flow. The compact structures of calcium oxalate monohydrate produced at low flow rates are replaced by the thermodynamically unstable calcium oxalate dihydrate favored in the presence of a strong gravity current.
Bone loss and human adaptation to lunar gravity
NASA Technical Reports Server (NTRS)
Keller, T. S.; Strauss, A. M.
1992-01-01
Long-duration space missions and establishment of permanently manned bases on the Moon and Mars are currently being planned. The weightless environment of space and the low-gravity environments of the Moon and Mars pose an unknown challenge to human habitability and survivability. Of particular concern in the medical research community today is the effect of less than Earth gravity on the human skeleton, since the limits, if any, of human endurance in low-gravity environments are unknown. This paper provides theoretical predictions on bone loss and skeletal adaptation to lunar and other nonterrestrial-gravity environments based upon the experimentally derived relationship, density approximately (mass x gravity)(exp 1/8). The predictions are compared to skeletal changes reported during bed rest, immobilization, certrifugation, and spaceflight. Countermeasures to reduce bone losses in fractional gravity are also discussed.
Study on shearing force and impact force of a volcanic mud flow on Mt. Sakurajima
Yoshinobu Taniguchi
1991-01-01
Two kinds of shearing stress meters (type A and type B) were set on the channel bottom in the Arimura River and the Mochiki River on Mt. Sakurajima. Volcanic mud flows take place there about 100 times a year. The results of the surveys demonstrated that the actual shearing force of a volcanic mud flow on Mt. Sakurajima was from 0.46 to 2.50 kgf/cm2...
A novel approach in red mud neutralization using cow dung.
Patel, Sucharita; Pal, Bhatu Kumar; Patel, Raj Kishore
2018-05-01
In this study, cow dung was identified as a neutralizing agent for red mud (RM). Present research estimated a significant reduction in pH value of red mud (10 g) from 10.28 to 8.15 and reduction in alkalinity of ~148 mg/L from ~488 mg/L by adding 80 g of cow dung in 40 days of anaerobic condition. XRD results exhibit a high intensity of quartz and found new compound, the calcium carbide. The acid neutralizing capacity (ANC) of NRM reduces to ~0.87 from ~1.506 mol H + /kg. Based on the resultant research, present study proposes cow dung as an efficient neutralizing agent for reducing the pH and alkalinity in the red mud.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matthews, Patrick
2006-09-01
In 2001, the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA/NSO) remediated six areas associated with Amchitka mud pit release sites located on Amchitka Island, Alaska. This included the construction of seven closure caps. To ensure the integrity and effectiveness of remedial action, the mud pit sites are to be inspected every five years as part of DOE's long-term monitoring and surveillance program. In August of 2006, the closure caps were inspected in accordance with the ''Post-Closure Monitoring and Inspection Plan for Amchitka Island Mud Pit Release Sites'' (Rev. 0, November 2005). This post-closure monitoring report provides themore » 2006 cap inspection results.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Valysaev, B.M.; Erokhin, V.E.; Grinchenko, Y.I.
A study has been made of the isotopic composition of the carbon in methane and carbon dioxide, as well as hydrogen in the methane, in the gases of mud volcanoes, for all main mud volcano areas in the USSR. The isotopic composition of carbon and hydrogen in methane shows that the gases resemble those of oil and gas deposits, while carbon dioxide of these volcanoes has a heavier isotopic composition with a greater presence of ''ultraheavy'' carbon dioxide. By the chemical and isotopic composition of gases, Azerbaidzhan and South Sakhalin types of mud volcano gases have been identified, as wellmore » as Bulganak subtypes and Akhtala and Kobystan varieties. Correlations are seen between the isotopic composition of gases and the geological build of mud volcano areas.« less
Effects of pore pressure and mud filtration on drilling rates in a permeable sandstone
DOE Office of Scientific and Technical Information (OSTI.GOV)
Black, A.D.; DiBona, B.; Sandstrom, J.
1983-10-01
During laboratory drilling tests in a permeable sandstone, the effects of pore pressure and mud filtration on penetration rates were measured. Four water-base muds were used to drill four saturated sandstone samples. The drilling tests were conducted at constant borehole pressure with different back pressures maintained on the filtrate flowing from the bottom of the sandstone samples. Bit weight was also varied. Filtration rates were measured while drilling and with the bit off bottom and mud circulating. Penetration rates were found to be related to the difference between the filtration rates measured while drilling and circulating. There was no observedmore » correlation between standard API filtration measurements and penetration rate.« less
Effects of pore pressure and mud filtration on drilling rates in a permeable sandstone
DOE Office of Scientific and Technical Information (OSTI.GOV)
Black, A.D.; Dearing, H.L.; DiBona, B.G.
1985-09-01
During laboratory drilling tests in a permeable sandstone, the effects of pore pressure and mud filtration on penetration rates were measured. Four water-based muds were used to drill four saturated sandstone samples. The drilling tests were conducted at constant borehole pressure while different backpressures were maintained on the filtrate flowing from the bottom of the sandstone samples. Bit weight was varied also. Filtration rates were measured while circulating mud during drilling and with the bit off bottom. Penetration rates were found to be related qualitatively to the difference between the filtration rates measured while drilling and circulating. There was nomore » observed correlation between standard API filtration measurements and penetration rate.« less
NASA Astrophysics Data System (ADS)
Francisco, E. P.; Espath, L. F. R.; Laizet, S.; Silvestrini, J. H.
2018-01-01
Three-dimensional highly resolved Direct Numerical Simulations (DNS) of particle-laden gravity currents are presented for the lock-exchange problem in an original basin configuration, similar to delta formation in lakes. For this numerical study, we focus on gravity currents over a flat bed for which density differences are small enough for the Boussinesq approximation to be valid. The concentration of particles is described in an Eulerian fashion by using a transport equation combined with the incompressible Navier-Stokes equations, with the possibility of particles deposition but no erosion nor re-suspension. The focus of this study is on the influence of the Reynolds number and settling velocity on the development of the current which can freely evolve in the streamwise and spanwise direction. It is shown that the settling velocity has a strong influence on the spatial extent of the current, the sedimentation rate, the suspended mass and the shape of the lobe-and-cleft structures while the Reynolds number is mainly affecting the size and number of vortical structures at the front of the current, and the energy budget.
Jones, Benjamin E H; Haynes, Richard J; Phillips, Ian R
2011-02-01
In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tone of alumina produced, about 2 tones of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation. Samples of freshly deposited residue sand were collected from Alcoa's Kwinana refinery. Samples were treated with phosphogypsum (2% v/v), incubated, and leached. A laboratory experiment was then set up in which the two organic wastes were applied at 0 or the equivalent to 60 tones ha(-1) in combination with residue mud added at rates of 0%, 10% and 20% v/v. Samples were incubated for 8 weeks, after which, key chemical, physical and microbial properties of the residue sand were measured along with seed germination. Additions of residue mud increased exchangeable Na(+), ESP and the pH, and HCO (3) (-) and Na(+) concentrations in saturation paste extracts. Additions of biosolids and poultry manure increased concentrations of extractable P, NH (4) (+) , K, Mg, Cu, Zn, Mn and Fe. Addition of residue mud, in combination with organic wastes, caused a marked decrease in macroporosity and a concomitant increase in mesoporosity, available water holding capacity and the quantity of water held at field capacity. With increasing residue mud additions, the percentage of sample present as sand particles (<1 mm diameter) decreased, and the percentage present in aggregated form (>2 mm diameter) increased; greatest aggregation occurred where a combination of residue mud and poultry manure were added. Stability of aggregates, as measured by wet sieving, was greatest where poultry manure was applied. Although total organic C and soluble organic C were greater in biosolids than poultry manure treatments, the reverse was the case for microbial biomass C and basal respiration. In the biosolids and poultry manure treatments, increasing residue mud additions tended to increase soluble C, microbial biomass C and basal respiration. Germination index of watercress was highest in control samples and reduced by additions of biosolids and poultry manure which was attributed to the high EC and possibly high extractable P and NH (4) (+) . The concurrent addition of residue mud and organic wastes can improve chemical, microbial and particularly physical properties of residue sand. Future research should include neutralisation of the mud (e.g. with gypsum) and subsequent leaching to remove salts originating from both the mud and organic wastes.
Wang, Hubiao; Wu, Lin; Chai, Hua; Xiao, Yaofei; Hsu, Houtse; Wang, Yong
2017-08-10
The variation of a marine gravity anomaly reference map is one of the important factors that affect the location accuracy of INS/Gravity integrated navigation systems in underwater navigation. In this study, based on marine gravity anomaly reference maps, new characteristic parameters of the gravity anomaly were constructed. Those characteristic values were calculated for 13 zones (105°-145° E, 0°-40° N) in the Western Pacific area, and simulation experiments of gravity matching-aided navigation were run. The influence of gravity variations on the accuracy of gravity matching-aided navigation was analyzed, and location accuracy of gravity matching in different zones was determined. Studies indicate that the new parameters may better characterize the marine gravity anomaly. Given the precision of current gravimeters and the resolution and accuracy of reference maps, the location accuracy of gravity matching in China's Western Pacific area is ~1.0-4.0 nautical miles (n miles). In particular, accuracy in regions around the South China Sea and Sulu Sea was the highest, better than 1.5 n miles. The gravity characteristic parameters identified herein and characteristic values calculated in various zones provide a reference for the selection of navigation area and planning of sailing routes under conditions requiring certain navigational accuracy.
Wang, Hubiao; Chai, Hua; Xiao, Yaofei; Hsu, Houtse; Wang, Yong
2017-01-01
The variation of a marine gravity anomaly reference map is one of the important factors that affect the location accuracy of INS/Gravity integrated navigation systems in underwater navigation. In this study, based on marine gravity anomaly reference maps, new characteristic parameters of the gravity anomaly were constructed. Those characteristic values were calculated for 13 zones (105°–145° E, 0°–40° N) in the Western Pacific area, and simulation experiments of gravity matching-aided navigation were run. The influence of gravity variations on the accuracy of gravity matching-aided navigation was analyzed, and location accuracy of gravity matching in different zones was determined. Studies indicate that the new parameters may better characterize the marine gravity anomaly. Given the precision of current gravimeters and the resolution and accuracy of reference maps, the location accuracy of gravity matching in China’s Western Pacific area is ~1.0–4.0 nautical miles (n miles). In particular, accuracy in regions around the South China Sea and Sulu Sea was the highest, better than 1.5 n miles. The gravity characteristic parameters identified herein and characteristic values calculated in various zones provide a reference for the selection of navigation area and planning of sailing routes under conditions requiring certain navigational accuracy. PMID:28796158
A study of inter-particle bonds in dry bauxite waste resulting in atmospheric aerosols
NASA Astrophysics Data System (ADS)
Wagh, Arun S.; Thompson, Bentley
1988-02-01
Bauxite and Alumina production are one of the main activities of several third world countries such as Jamaica, Brazil, India, Guinea, eastern European countries such as Hungary and Rumania and advanced countries such as Australia, West Germany, Japan and the United States. The mining operations lead to dust pollution, but the refining of bauxite to alumina yield large amounts of highly caustic sludge waste, called "Red Mud". Millions of tons of the waste produced in every country are stored in containment dams or natural valleys. This leads to ground water pollution, destruction of plant and bird life and is hazardous to human settlement in earthquake prone regions like Jamaica. As a result several companies have been looking into dry mud stacking which involves thickening the mud in the refining plants and sprying it on the slopes to sun dry it. Typically it involves a drying field of about two hundred acres, which could act as a potential source of caustic dust. In Jamaica one company has started disposing of the mud in this way. The aerosol formation from such areas depends mainly on the integrity of the top dry layers. Presently this is done by studying the approximate parameters such as the friability of the mud. However, following the recent advances in powder technology it has been possible for us to develop an instrument to study the average interparticle forces between the red mud particles. The instrument is based on the principle of a tensometer and a split cell is used to load specimens. A load cell is used to measure the force and a chart recorder is used for plotting separation and the force. The present study reports elemental composition of the dust and its health hazards. It also reports the physical measurement of the average interparticle force as a function of their separation in the Jamaican mud. The effect of ultraviolet radiation on the strength of the material is studied to see the effect of sun-drying of the waste. The five-fold increase in tensile strength indicates that laterisation process is responsible for this phenomenon in Jamaican red mud. The study is crucial to the development of dust free mud stacking by the proper modifications in the process technology. Finally, such a case study is general enough in the characterisation of other sources of aerosols.
Cosmic history of chameleonic dark matter in F (R ) gravity
NASA Astrophysics Data System (ADS)
Katsuragawa, Taishi; Matsuzaki, Shinya
2018-03-01
We study the cosmic history of the scalaron in F (R ) gravity with constructing the time evolution of the cosmic environment and discuss the chameleonic dark matter based on the chameleon mechanism in the early and current Universe. We then find that the scalaron can be a dark matter. We also propose an interesting possibility that the F (R ) gravity can address the coincidence problem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gordon Tibbitts; Arnis Judzis
2002-04-01
This document details the progress to date on the OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE--A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING contract for the quarter starting January 2002 through March 2002. Accomplishments include the following: In accordance to Task 7.0 (D. No.2 Technical Publications) TerraTek, NETL, and the Industry Contributors successfully presented a paper detailing Phase 1 testing results at the February 2002 IADC/SPE Drilling Conference, a prestigious venue for presenting DOE and private sector drilling technology advances. The full reference is as follows: (1) IADC/SPE 74540 ''World's First Benchmarking of Drilling Mud Hammer Performance atmore » Depth Conditions'' authored by Gordon A. Tibbitts, TerraTek; Roy C. Long, US Department of Energy, Brian E. Miller, BP America, Inc.; Arnis Judzis, TerraTek; and Alan D. Black, TerraTek. Gordon Tibbitts, TerraTek, will presented the well-attended paper in February of 2002. The full text of the Mud Hammer paper was included in the last quarterly report. (2) The Phase 2 project planning meeting (Task 6) was held at ExxonMobil's Houston Greenspoint offices on February 22, 2002. In attendance were representatives from TerraTek, DOE, BP, ExxonMobil, PDVSA, Novatek, and SDS Digger Tools. (3) PDVSA has joined the advisory board to this DOE mud hammer project. PDVSA's commitment of cash and in-kind contributions were reported during the last quarter. (4) Strong Industry support remains for the DOE project. Both Andergauge and Smith Tools have expressed an interest in participating in the ''optimization'' phase of the program. The potential for increased testing with additional Industry cash support was discussed at the planning meeting in February 2002.« less
Quantitative X-ray Diffraction (QXRD) analysis for revealing thermal transformations of red mud.
Liao, Chang-Zhong; Zeng, Lingmin; Shih, Kaimin
2015-07-01
Red mud is a worldwide environmental problem, and many authorities are trying to find an economic solution for its beneficial application or/and safe disposal. Ceramic production is one of the potential waste-to-resource strategies for using red mud as a raw material. Before implementing such a strategy, an unambiguous understanding of the reaction behavior of red mud under thermal conditions is essential. In this study, the phase compositions and transformation processes were revealed for the Pingguo red mud (PRM) heat-treated at different sintering temperatures. Hematite, perovskite, andradite, cancrinite, kaolinite, diaspore, gibbsite and calcite phases were observed in the samples. However, unlike those red mud samples from the other regions, no TiO2 (rutile or anatase) or quartz were observed. Titanium was found to exist mainly in perovskite and andradite while the iron mainly existed in hematite and andradite. A new silico-ferrite of calcium and aluminum (SFCA) phase was found in samples treated at temperatures above 1100°C, and two possible formation pathways for SFCA were suggested. This is the first SFCA phase to be reported in thermally treated red mud, and this finding may turn PRM waste into a material resource for the iron-making industry. Titanium was found to be enriched in the perovskite phase after 1200°C thermal treatment, and this observation indicated a potential strategy for the recovery of titanium from PRM. In addition to noting these various resource recovery opportunities, this is also the first study to quantitatively summarize the reaction details of PRM phase transformations at various temperatures. Copyright © 2015 Elsevier Ltd. All rights reserved.
Mechanism of red mud combined with Fenton's reagent in sewage sludge conditioning.
Zhang, Hao; Yang, Jiakuan; Yu, Wenbo; Luo, Sen; Peng, Li; Shen, Xingxing; Shi, Yafei; Zhang, Shinan; Song, Jian; Ye, Nan; Li, Ye; Yang, Changzhu; Liang, Sha
2014-08-01
Red mud was evaluated as an alternative skeleton builder combined with Fenton's reagent in sewage sludge conditioning. The results show that red mud combined with Fenton's reagent showed good conditioning capability with the pH of the filtrate close to neutrality, indicating that red mud acted as a neutralizer as well as a skeleton builder when jointly used with Fenton's reagent. Through response surface methodology (RSM), the optimal dosages of Fe(2+), H2O2 and red mud were proposed as 31.9, 33.7 and 275.1 mg/g DS (dry solids), respectively. The mechanism of the composite conditioner could be illuminated as follows: (1) extracellular polymeric substances (EPS), including loosely bound EPS and tightly bound EPS, were degraded into dissolved organics, e.g., proteins and polysaccharides; (2) bound water was released and converted into free water due to the degradation of EPS; and (3) morphology of the conditioned sludge exhibited a porous structure in contrast with the compact structure of raw sludge, and the addition of red mud formed new mineral phases and a rigid lattice structure in sludge, allowing the outflow of free water. Thus, sludge dewatering performance was effectively improved. The economic assessment for a wastewater treatment plant of 370,000 equivalent inhabitants confirms that using red mud conditioning, combined with Fenton's reagent, leads to a saving of approximately 411,000 USD/y or 50.8 USD/t DS comparing with using lime and ordinary Portland cement combined with Fenton's reagent, and approximately 612,000 USD/y or 75.5 USD/t DS comparing with the traditional treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.
Tao, Yong; Li, Jiabao; Rui, Junpeng; Xu, Zhancheng; Zhou, Yan; Hu, Xiaohong; Wang, Xiang; Liu, Menghua; Li, Daping
2014-01-01
Chinese strong-flavored liquor (CSFL) accounts for more than 70% of all Chinese liquor production. Microbes in pit mud play key roles in the fermentation cellar for the CSFL production. However, microbial diversity, community structure, and cellar-age-related changes in pit mud are poorly understood. Here, we investigated the prokaryotic community structure and diversity in pit-mud samples with different cellar ages (1, 10, 25, and 50 years) using the pyrosequencing technique. Results indicated that prokaryotic diversity increased with cellar age until the age reached 25 years and that prokaryotic community structure changed significantly between three cellar ages (1, 10, and 25 years). Significant correlations between prokaryotic communities and environmental variables (pH, NH4+, lactic acid, butyric acid, and caproic acid) were observed. Overall, our study results suggested that the long-term brewing operation shapes unique prokaryotic community structure and diversity as well as pit-mud chemistry. We have proposed a three-phase model to characterize the changes of pit-mud prokaryotic communities. (i) Phase I is an initial domestication period. Pit mud is characterized by abundant Lactobacillus and high lactic acid and low pH levels. (ii) Phase II is a transition period. While Lactobacillus abundance decreases dramatically, that of Bacteroidetes and methanogens increases. (iii) Phase III is a relative mature period. The prokaryotic community shows the highest diversity and capability to produce more caproic acid as a precursor for synthesis of ethyl caproate, the main flavor component in CSFL. This research provides scientific evidence to support the practical experience that old fermentation cellars produce high-quality liquor. PMID:24487528
Shen, Yuan; Cao, Min-Jie; Cai, Qiu-Feng; Su, Wen-Jin; Yu, Hui-Lin; Ruan, Wei-Wei; Liu, Guang-Ming
2011-05-01
Although crustaceans have been reported to be one of the most common causes of IgE-mediated allergic reactions, there are no reports about the characterization and identification of arginine kinase (AK) from the mud crab (Scylla serrata) as allergen. In the present study, the purification, molecular cloning, expression and immunological analyses of the IgE allergen AK from the mud crab were investigated. The results showed that cloned DNA fragments of AK from the mud crab had open reading frames of 1021 bp, predicted to encode proteins with 356 amino acid residues. Sequence alignment revealed that mud crab AK shares high homology with other crustacean species. Mud crab AK gene was further recombined with the vector of pGEX-4T-3 and expressed in Escherichia coli BL 21. 2-D electrophoresis suggested that native AK (nAK) and recombinant AK (rAK) shared the same molecular weight of 40 kDa, and the pI is 6.5 and 6.3, respectively. The nAK and rAK were further confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Immunoblotting analysis and colloidal gold immunochromatographic assay (GICA) using sera from subjects with crustacean allergy confirmed that the nAK and rAK reacted positively with these sera, indicating AK is a specific allergen of mud crab. Both of purified nAK and rAK reacted positively with sera from subjects with crustacean allergy in immunoblotting and GICA analysis, indicating AK is a common allergen of mud crab. In vitro expressed AK is proposed as a source of the protein for immunological or clinical studies. Copyright © 2011 Society of Chemical Industry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
King, D.T. Jr.
1990-05-01
Tournasian-early Visean mud mounds (i.e., Waulsortian and Waulsortian-like mounds) are unlike other carbonate buildups in the stratigraphic record because they lack an identifiable frame-building organism. Waulsortian mounds are comprised mainly of carbonate mud; Waulsortian-like mounds are mud-rich and contain a significant percent of skeletal grains, especially crinoids and bryozoa. This study has revealed that all of the reported Waulsortian and Waulsortian-like mounds developed in low paleolatitudes either on the southern shelf margin of the Laurussian paleocontinent or in the Laurussian interior seaway. Waulsortian and Waulsortian-like mounds are specifically not present in low-latitude regions of other paleocontinents. As Tournasian-early Visean carbonatemore » deposition was widespread in the range of 30{degree}N to 10{degree}S, the very restricted paleogeographic distribution of Waulsortian and Waulsortian-like mound locations suggests a mechanism or set of conditions that effectively limited the distribution of mud mounds. Considering the Tournasian-early Visean distribution of paleocontinents and the principles that govern the movement of modern hurricanes, tropical storms, and winter storms, the tracts of hurricanes, tropical storms, and winter storms probably crossed all main submerged paleocontinental areas except the southern Laurussian shelf margin and the Laurussian interior seaway, the two areas where mud mounds developed. The lack of storm energy in these two large areas of Laurussia provided long-term stability and thus enhanced the growth prospects of the frame-deficient Waulsortian and Waulsortian-like mud mounds. Lack of extensive periodic wave reworking and other storm-induced devastation helps to account for enigmatic features such as general mound symmetry, great size, high depositional relief (as much as 220 m), and side steepness (as steep as 50{degree}).« less
Experimental Study of Sand Production and Mud Erosion Phenomena for Sand Mud Alternate Layer
NASA Astrophysics Data System (ADS)
Oyama, H.; Sato, T.
2014-12-01
Methane hydrates are crystalline, ice-like compounds under specific thermodynamic conditions. The existence of methane hydrates is confirmed in the Nankai Trough, an offshore area of Japan. Japan's Methane Hydrate Research and Development Program (MH21) has been under way at this area. In the early 2013, the world's first intentional gas production attempt from marine gas hydrate deposits was tried and accomplished in the Daini Atumi Knoll area of the Eastern Nankai Trough. For gas production, depressurization method has been considered as a promising gas production technique from methane hydrate reservoirs. However, considering of continuous gas production over a long period, there is still something to clarify. The methane hydrate crystals are very small and existed in the intergranular pores of sandy layer of turbidite sediments. When the intergranular methane hydrates will be dissociated, it is considered that dissociated gas and water flow will cause sand production and mud erosion phenomena of turbidite sediments. The production of framework sands into a well is one of the problems plaguing the gas because of its adverse effects on well productivity and equipment. If the eroded mud is accumulated in the pore space of sand, skin is generated and permeability becomes lower. In addition, mud erosion has a negative effect for the well stability. This research presents an experimental study to understand sand production and mud erosion phenomena for sand mud alternate layer. The aims of this study are to understand these phenomena and clarify driving forces. In our experiments, we used an artificial sedimentary core and performed experiments under various conditions. As the results, the driving forces of these phenomena are not dissociation gas flow but water flow through pore.
Chae, Seong Chun; Kwon, Young Hyun; Min, Kyung Il; Kim, Hyung Soo; Kim, Nam-Jin; Kim, Jun-Ran; Son, Bong Gi; Ahn, Young-Joon
2014-07-01
Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae.
Comparison of health service use among veterans with methamphetamine versus alcohol use disorders.
Morasco, Benjamin J; OʼNeil, Maya E; Duckart, Jonathan P; Ganzini, Linda
2014-01-01
Methamphetamine use disorders (MUD) are associated with severe health effects and psychiatric comorbidities, but little is known about the health care utilization of patients with MUD. The goal of this study was to describe health service use among veterans with MUD relative to a group of veterans with an alcohol use disorder (AUD). Using Veterans Affairs (VA) administrative data, we identified 718 patients who were diagnosed with MUD and had confirmatory drug testing. Data were compared with those of 744 patients who had diagnoses of an AUD also with confirmatory testing. We examined diagnoses and medical utilization for 5 years after their index date. Patients with MUD and laboratory-confirmed recent use were younger and more likely to be diagnosed with a mood disorder, posttraumatic stress disorder, and a psychotic-spectrum disorder (all P values < 0.05). After statistical controls, patients with MUD were more likely to have an inpatient hospitalization (80% vs 70%, odds ratio [OR] = 1.8; 95% confidence interval [CI] = 1.4-2.3), discharge from an inpatient admission against medical advice (23.4% vs 8.3%, OR = 2.6, 95% CI = 1.9-3.7), receive care at 3 or more VA medical centers (13.1% vs 5.4%, OR = 2.3, 95% CI = 1.5-3.5), have a behavioral flag in the medical record (5.6% vs 1.1%, OR = 4.6, 95% CI = 2.1-10.6), and have more total missed appointments in the 5-year study period (M = 33.1 vs M = 23.5, P < 0.001). Among veterans with substance use disorders, those with MUD and laboratory-confirmed recent use have additional behavioral, health care utilization, and psychiatric characteristics that need to be considered in developing programs of care.
NASA Astrophysics Data System (ADS)
Antonielli, Benedetta; Monserrat, Oriol; Bonini, Marco; Righini, Gaia; Sani, Federico; Luzi, Guido; Feyzullayev, Akper A.; Aliyev, Chingiz S.
2014-12-01
Mud volcanism is a process that leads to the extrusion of subsurface mud, fragments of country rocks, saline waters and gases. This mechanism is typically linked to hydrocarbon traps, and the extrusion of this material builds up a variety of conical edifices with a similar morphology to those of magmatic volcanoes, though smaller in size. The Differential Interferometry Synthetic Aperture Radar (DInSAR) technique has been used to investigate the ground deformation related to the activity of the mud volcanoes of Azerbaijan. The analysis of a set of wrapped and unwrapped interferograms, selected according to their coherence, allowed the detection of significant superficial deformation related to the activity of four mud volcanoes. The ground displacement patterns observed during the period spanning from October 2003 to November 2005 are dominated by uplift, which reach a cumulative value of up to 20 and 10 cm at the Ayaz-Akhtarma and Khara-Zira Island mud volcanoes, respectively. However, some sectors of the mud volcano edifices are affected by subsidence, which might correspond to deflation zones that coexist with the inflation zones characterized by the dominant uplift. Important deformation events, caused by fluid pressure and volume variations, have been observed both (1) in connection with main eruptive events in the form of pre-eruptive uplift, and (2) in the form of short-lived deformation pulses that interrupt a period of quiescence. Both deformation patterns show important similarities to those identified in some magmatic systems. The pre-eruptive uplift has been observed in many magmatic volcanoes as a consequence of magma intrusion or hydrothermal fluid injection. Moreover, discrete short-duration pulses of deformation are also experienced by magmatic volcanoes and are repeated over time as multiple inflation and deflation events.
Riding gravity away from doomsday
NASA Astrophysics Data System (ADS)
Sen, Ashoke
2015-09-01
The discovery that most of the energy density in the universe is stored in the form of dark energy has profound consequences for our future. In particular, our current limited understanding of quantum theory of gravity indicates that some time in the future, our universe will undergo a phase transition that will destroy us and everything else around us instantaneously. However, the laws of gravity also suggest a way out — some of our descendants could survive this catastrophe by riding gravity away from the danger. This paper describes the tale of this escape from doomsday.
Einstein-Yang-Mills-Dirac systems from the discretized Kaluza-Klein theory
NASA Astrophysics Data System (ADS)
Wali, Kameshwar; Viet, Nguyen Ali
2017-01-01
A unified theory of the non-Abelian gauge interactions with gravity in the framework of a discretized Kaluza-Klein theory is constructed with a modified Dirac operator and wedge product. All the couplings of chiral spinors to the non-Abelian gauge fields emerge naturally as components of the coupling of the chiral spinors in the generalized gravity together with some new interactions. In particular, the currently prevailing gravity-QCD quark and gravity-electroweak-quark and lepton models are shown to follow as special cases of the general framework.
1944-03-01
Scope 1 II AUTHORITY 1 2. Directives 1 III PREVIOUS INVESTIGATION 1 3 . Summary 1 IV PRES {T INVESTIGATION 2 4. Purpose of Tests 2 5. Tests Conducted... 3 V DISCUSSION 3 6. Importanc-? of Tosts 3 7. The Low Pressure Tire 3 8. Mud Conditions 4 9. Factors Influencing laud Porformanco 4 10. Reasons for...data on general service durability, which is * deemed satisfactory, are included in the report. 3 . The report concludes that mud performance of those
Testing of Compounds for Efficacy against Schistosomiasis.
1986-07-22
4); 2) a petri dish containing a centrally placed mud mound, blue-green aglae ( Nostoc muscorum) and water Is used for rearing young snails and...maintaining both pre-exposed and exposed snails (5); 3) a petri dish containing small amounts of blue-green algae ( Nostoc muscoru), mud and water is used...25-27 C. 4. Food. Blue-green algae ( Nostoc muscorum) grown in petri dishes with mud (5) is used exclusively as the food source. C. Breedin A
Estimation of bioavailability of metals from drilling mud barite.
Neff, Jerry M
2008-04-01
Drilling mud and associated drill cuttings are the largest volume wastes associated with drilling of oil and gas wells and often are discharged to the ocean from offshore drilling platforms. Barite (BaSO4) often is added as a weighting agent to drilling muds to counteract pressure in the geologic formations being drilled, preventing a blowout. Some commercial drilling mud barites contain elevated (compared to marine sediments) concentrations of several metals. The metals, if bioavailable, may harm the local marine ecosystem. The bioavailable fraction of metals is the fraction that dissolves from the nearly insoluble, solid barite into seawater or sediment porewater. Barite-seawater and barite-porewater distribution coefficients (Kd) were calculated for determining the predicted environmental concentration (PEC; the bioavailable fraction) of metals from drilling mud barite in the water column and sediments, respectively. Values for Kdbarite-seawater and Kdbarite-porewater were calculated for barium, cadmium, chromium, copper, mercury, lead, and zinc in different grades of barite. Log Kdbarite-seawater values were higher (solubility was lower) for metals in the produced water plume than log Kdbarite-porewater values for metals in sediments. The most soluble metals were cadmium and zinc and the least soluble were mercury and copper. Log Kd values can be used with data on concentrations of metals in barite and of barite in the drilling mud-cuttings plume and in bottom sediments to calculate PECseawater and PECsediment.
Composites based on PET and red mud residues as catalyst for organic removal from water.
Bento, Natálya I; Santos, Patrícia S C; de Souza, Talita E; Oliveira, Luiz C A; Castro, Cínthia S
2016-08-15
In this study, we obtained a composite based on carbon/iron oxide from red mud and PET (poly(ethylene terephthalate)) wastes by mechanical mixture (10, 15 and 20wt.% of PET powder/red mud) followed by a controlled thermal treatment at 400°C under air. XRD analyses revealed that the α-Fe2O3 is the main phase formed from red mud. TPR analyses showed that the iron oxide present in the composites undergoes reduction at lower temperature to form Fe(2+) species present in Fe3O4, indicating that the iron oxide in the composite can exhibit greater reactivity in the catalytic processes compared to the original red mud. In fact, catalytic tests showed that the composites presented higher capacity to remove methylene blue dye (MB), presenting about 90% of removal after 24h of reaction. The MB removal was also monitored by mass spectrometer with ionization via electrospray (ESI-MS), which demonstrated the occurrence of the oxidation process, showing the formation of MB oxidation products. The stability of the composites was confirmed after four reuse cycles. The results seem to indicate that PET carbon deposited over the iron oxide from red mud promotes adsorption of the contaminant allowing its contact with the iron atoms and their consequent reaction. Copyright © 2016 Elsevier B.V. All rights reserved.
Oil Palm Empty Fruit Bunch (OPEFB) Fiber as Lost Circulation Material (LCM) in Water Based Mud (WBM)
NASA Astrophysics Data System (ADS)
Ghazali, N. A.; Sauki, A.; Abu Bakar, N. F.; Mohamed, S.
2018-05-01
Lost Circulation Material (LCM) is an additive used to prevent lost of mud to the formation as a results from natural or induced fractured during drilling operation. Losses of mud could give great impact to the oil industry as it increases mud cost and rig time. The objective of this research was to investigate the effect of size and concentration of Oil Palm Empty Fruit Bunch (OPEFB) as LCM in water based mud (WBM). Several important properties of WBM rheology after adding the OPEFB namely plastic viscosity, apparent viscosity, yield point and gel strength were characterized. The sizes of OPEFB added into the WBM were 150μm, 250μm, 500μm and 1000μm while the concentration of OPEFB used were 5g, 10g, 15g and 20g in 350 mL of WBM. Results indicated that the plastic viscosity and apparent viscosity increased with increasing of the OPEFB concentrations. On the other hand, the plastic viscosity and apparent viscosity decreased with increasing sizes of OPEFB. Yield point increased as the concentration and size of OPEFB increases. This study indicated that OPEFB was effective to be used as LCM for size of 150μm and concentration of 15g whereby it produced least amount of filtrate volume as well as good control in mud rheology.
NASA Astrophysics Data System (ADS)
Alissianto, Y. R.; Sandriani, Z. A.; Rahardja, B. S.; Agustono; Rozi
2018-04-01
High market demand of mud crab (Scylla serrata) encourages farmers to increase the production of mud crab. However, mud crab can not synthesize essential amino acids, so it is necessary to supply essential amino acids such as lysine and methionine in the diet. This study aims to determine the effect of lysine and methionine on feeds to increase growth and retention of mud crabs (Scylla serrata). In this study the amount of lysine amino acid and methionine added to the trash fish diet were: P0 (0: 0%); P1 (0.75: 0.75%); P2 (1: 1%); P3 (1.25: 1.25%); P4 (1.5: 1.5%) with the ratio of lysine and methionine 1: 1. The parameters observed in this study were Survival Rate (SR), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR), Efficiency Feed (EF), protein retention and energy retention. The results of the 35-day maintenance study showed significant differences (P <0.05) against Specific Growth Rate (SGR), Feed Conversion Ratio (FCR), Efficiency Feed (EF), protein retention and no significant effect (P> 0.05) on energy retention and Survival Rate (SR) on mud crab. The best results in this study were found in P4 treatment with addition of lysine amino acids and methionine (1.5: 1.5%).
Clinical and anti-aging effect of mud-bathing therapy for patients with fibromyalgia.
Maeda, Toyoki; Kudo, Yoshihiro; Horiuchi, Takahiko; Makino, Naoki
2017-12-06
Spa bathing is known as a medical treatment for certain diseases causing chronic pains. Spa water contains mineral components which lower the specific heat of the water, resulting in a higher efficiency to warm body-core temperature. This phenomenon yields pain-relieving effect for rheumatoid arthritis, low back pain, sciatic neuralgia, fibromyalgia, etc. Here we introduce medical and biological effects of mud-spa-bathing therapy for fibromyalgia other than pain relief, the changes of blood examination data, and the telomere length of circulating leukocytes. The enrolled 7 patients with fibromyalgia syndrome were hospitalized and were subject to daily mud bathing at 40 °C for 10 min for about a month. Then, their subjective pain was reduced to about a quarter in average. They also showed lowered serum triglyceride and C-reactive protein level, maintaining the levels of aspartate transaminase and creatine phosphokinase, and increases of the red blood cell count, the serum albumin level, and the serum LDL-cholesterol level in comparison with cases without mud-bathing therapy, suggesting that mud bathing prevents inflammation and muscle atrophy and improves nutritional condition in fibromyalgia. In addition, the analysis of telomere length of peripheral leukocytes revealed a trend of negative correlation between telomere shortening and laboratory data change of hemoglobin and serum albumin. These telomeric changes can be explained hypothetically by an effect of mud bathing extending life-span of circulating leukocytes.
NASA Astrophysics Data System (ADS)
Gong, Zheng; Li, Haibing; Tang, Lijun; Lao, Changling; Zhang, Lei; Li, Li
2017-05-01
We investigated the real time drilling mud gas of the Wenchuan earthquake Fault Scientific Drilling Hole-1 and their responses to 3918 small-moderate aftershocks happened in the Longmenshan fault zone. Gas profiles for Ar, CH4, He, 222Rn, CO2, H2, N2, O2 are obtained. Seismic wave amplitude, energy density and static strain are calculated to evaluate their power of influence to the drilling site. Mud gases two hours before and after each earthquake are carefully analyzed. In total, 25 aftershocks have major mud gas response, the mud gas concentrations vary dramatically immediately or minutes after the earthquakes. Different gas species respond to earthquakes in different manners according to local lithology encountered during the drill. The gas variations are likely controlled by dynamic stress changes, rather than static stress changes. They have the seismic energy density between 10-5 and 1.0 J/m3 whereas the static strain are mostly less than 10-8. We suggest that the limitation of the gas sources and the high hydraulic diffusivity of the newly ruptured fault zone could have inhibited the drilling mud gas behaviors, they are only able to respond to a small portion of the aftershocks. This work is important for the understanding of earthquake related hydrological changes.
Limitations of microbial hydrocarbon degradation at the Amon mud volcano (Nile deep-sea fan)
NASA Astrophysics Data System (ADS)
Felden, J.; Lichtschlag, A.; Wenzhöfer, F.; de Beer, D.; Feseker, T.; Pop Ristova, P.; de Lange, G.; Boetius, A.
2013-05-01
The Amon mud volcano (MV), located at 1250 m water depth on the Nile deep-sea fan, is known for its active emission of methane and non-methane hydrocarbons into the hydrosphere. Previous investigations showed a low efficiency of hydrocarbon-degrading anaerobic microbial communities inhabiting the Amon MV center in the presence of sulfate and hydrocarbons in the seeping subsurface fluids. By comparing spatial and temporal patterns of in situ biogeochemical fluxes, temperature gradients, pore water composition, and microbial activities over 3 yr, we investigated why the activity of anaerobic hydrocarbon degraders can be low despite high energy supplies. We found that the central dome of the Amon MV, as well as a lateral mud flow at its base, showed signs of recent exposure of hot subsurface muds lacking active hydrocarbon degrading communities. In these highly disturbed areas, anaerobic degradation of methane was less than 2% of the methane flux. Rather high oxygen consumption rates compared to low sulfide production suggest a faster development of more rapidly growing aerobic hydrocarbon degraders in highly disturbed areas. In contrast, the more stabilized muds surrounding the central gas and fluid conduits hosted active anaerobic hydrocarbon-degrading microbial communities. The low microbial activity in the hydrocarbon-vented areas of Amon MV is thus a consequence of kinetic limitations by heat and mud expulsion, whereas most of the outer MV area is limited by hydrocarbon transport.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arnis Judzis
2003-01-01
This document details the progress to date on the ''OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE -- A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING'' contract for the quarter starting October 2002 through December 2002. Even though we are awaiting the optimization portion of the testing program, accomplishments included the following: (1) Smith International participated in the DOE Mud Hammer program through full scale benchmarking testing during the week of 4 November 2003. (2) TerraTek acknowledges Smith International, BP America, PDVSA, and ConocoPhillips for cost-sharing the Smith benchmarking tests allowing extension of the contract to add to themore » benchmarking testing program. (3) Following the benchmark testing of the Smith International hammer, representatives from DOE/NETL, TerraTek, Smith International and PDVSA met at TerraTek in Salt Lake City to review observations, performance and views on the optimization step for 2003. (4) The December 2002 issue of Journal of Petroleum Technology (Society of Petroleum Engineers) highlighted the DOE fluid hammer testing program and reviewed last years paper on the benchmark performance of the SDS Digger and Novatek hammers. (5) TerraTek's Sid Green presented a technical review for DOE/NETL personnel in Morgantown on ''Impact Rock Breakage'' and its importance on improving fluid hammer performance. Much discussion has taken place on the issues surrounding mud hammer performance at depth conditions.« less
Symons, William O.; Sumner, Esther J.; Paull, Charles K.; Cartigny, Matthieu J.B.; Xu, Jingping; Maier, Katherine L.; Lorenson, Thomas; Talling, Peter J.
2017-01-01
Submarine turbidity currents create some of the largest sediment accumulations on Earth, yet there are few direct measurements of these flows. Instead, most of our understanding of turbidity currents results from analyzing their deposits in the sedimentary record. However, the lack of direct flow measurements means that there is considerable debate regarding how to interpret flow properties from ancient deposits. This novel study combines detailed flow monitoring with unusually precisely located cores at different heights, and multiple locations, within the Monterey submarine canyon, offshore California, USA. Dating demonstrates that the cores include the time interval that flows were monitored in the canyon, albeit individual layers cannot be tied to specific flows. There is good correlation between grain sizes collected by traps within the flow and grain sizes measured in cores from similar heights on the canyon walls. Synthesis of flow and deposit data suggests that turbidity currents sourced from the upper reaches of Monterey Canyon comprise three flow phases. Initially, a thin (38–50 m) powerful flow in the upper canyon can transport, tilt, and break the most proximal moorings and deposit chaotic sands and gravel on the canyon floor. The initially thin flow front then thickens and deposits interbedded sands and silty muds on the canyon walls as much as 62 m above the canyon floor. Finally, the flow thickens along its length, thus lofting silty mud and depositing it at greater altitudes than the previous deposits and in excess of 70 m altitude.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phelps, J.; Hoopingarner, J.
Effective techniques have been developed from work on dozens of North Sea Wells to minimize the amount of oil-based mud discharged to the sea while maintaining acceptable levels of solids. Pressure to reduce pollution during the course of drilling prompted the development of these techniques. They involve personnel and optimization of mud system and procedures. Case histories demonstrate that regulations may be met with economical techniques using existing technology. The benefits of low solids content are widely known, and are a key part of any successful mud program. Good solids control should result in lower mud costs and better drillingmore » performance. Operators have specified high-performance shakers to accomplish this and have revised their mud programs with lower and lower allowable drilled solids percentages. This will pay off in certain areas. But with the U.K. Department of Energy regulations requiring cuttings oil discharge content (CODC) to be less than 150 g of oil/kg of dry solids discharge that went into effect Jan. 1, 1989, oil-loss control has a higher profile in the U.K. sector of the North Sea.« less
A double-regulated oncolytic adenovirus with improved safety for adenocarcinoma therapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wei, Na; Fan, Jun Kai; Gu, Jin Fa
2009-10-16
Safety and efficiency are equally important to be considered in developing oncolytic adenovirus. Previously, we have reported that ZD55, an oncolytic adenovirus with the deletion of E1B-55K gene, exhibited potent antitumor activity. In this study, to improve the safety of ZD55, we utilized MUC1 promoter to replace the native promoter of E1A on the basis of ZD55, and generated a double-regulated adenovirus, named MUD55. Our data demonstrated that the expression of early and late genes of MUD55 was both reduced in MUC1-negative cells, resulting in its stricter glandular-tumor selective progeny production. The cytopathic effect of MUD55 was about 10-fold lowermore » than mono-regulated adenovirus ZD55 or Ad.MUC1 in normal cells and not obviously attenuated in glandular tumor cells. Moreover, MUD55 showed the least liver toxicity when administrated by intravenous injection in nude mice. These results indicate that MUD55 could be a promising candidate for the treatment of adenocarcinoma.« less
NASA Astrophysics Data System (ADS)
Gaevaya, E. V.; Bogaychuk, Y. E.; Tarasova, S. S.; Skipin, L. N.; Zaharova, E. V.
2017-10-01
The article considers the results of studies of the chemical and granulometric content and the factor of bore mud filtration in the process of its utilization. When the phosphogypsum is added, hydrophysical properties of the bore mud improve. At the same time, gradation of soil from the water-proof to weakly permeable takes place. This phenomenon is connected with recovery of filterability at the expense of ion-exchange reaction and a decrease of the silt fraction content in the bore mud. During the adding of phosphogypsum in the bore mud, pH decreased and made up 7.6-7.8 U. The decrease of the concentration of chloride-ions and sulphate-ions took place at the expense of replacement of Na+ by cations of Ca2+ that contributed to the formation of the water-stable structure with good filterability. The content of total forms of heavy metals in man-induced soil was lower than MAC (APC) for the loams. Man-induced soil has a V class of danger for the surrounding environment.
NASA Astrophysics Data System (ADS)
Shchepetkina, Alina; Gingras, Murray K.; Zonneveld, John-Paul; Pemberton, S. George
2016-03-01
The study provides a detailed description of mud-dominated sedimentary fabrics and their application for the rock record within the inner estuary to the fluvial zone of the Petitcodiac River estuary, New Brunswick, Canada. Sedimentological characteristics and facies distributions of the clay- and silt-rich deposits are reported. The inner estuary is characterized by thick accumulations of interbedded silt and silty clay on intertidal banks that flank the tidally influenced channel. The most common sedimentary structures observed are parallel and wavy lamination, small-scale soft-sediment deformation with microfaults, and clay and silt current ripples. The tidal channel contains sandy silt and clayey silt with planar lamination, massive and convolute bedding. The fluvio-tidal transition zone is represented by interbedded trough cross-stratified sand and gravel beds with planar laminated to massive silty mud. The riverine, non-tidal reach of the estuary is characterized by massive, planar tabular and trough cross-stratified gravel-bed deposits. The absence of bioturbation within the inner estuary to the fluvio-tidal transition zone can be explained by the following factors: low water salinities (0-5 ppt), amplified tide and current speeds, and high concentrations of flocculated material in the water body. Notably, downstream in the middle and outer estuary, bioturbation is seasonally pervasive: in those locales the sedimentary conditions are similar, but salinity is higher. In this study, the sedimentological (i.e., grain size, bedding characters, sedimentary structures) differences between the tidal estuary and the fluvial setting are substantial, and those changes occur over only a few hundred meters. This suggests that the widely used concept of an extensive fluvio-tidal transition zone and its depositional character may not be a geographically significant component of fluvial or estuary deposits, which can go unnoticed in the study of the ancient rocks.