33 CFR 165.1199 - Security Zones; Military Ocean Terminal Concord (MOTCO), Concord, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zones; Military Ocean... Coast Guard District § 165.1199 Security Zones; Military Ocean Terminal Concord (MOTCO), Concord..., extending from the surface to the sea floor, within 500 yards of the three Military Ocean Terminal Concord...

33 CFR 165.1199 - Security Zones; Military Ocean Terminal Concord (MOTCO), Concord, California.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zones; Military Ocean... Coast Guard District § 165.1199 Security Zones; Military Ocean Terminal Concord (MOTCO), Concord..., extending from the surface to the sea floor, within 500 yards of the three Military Ocean Terminal Concord...

33 CFR 165.1199 - Security Zones; Military Ocean Terminal Concord (MOTCO), Concord, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Security Zones; Military Ocean... Coast Guard District § 165.1199 Security Zones; Military Ocean Terminal Concord (MOTCO), Concord..., extending from the surface to the sea floor, within 500 yards of the three Military Ocean Terminal Concord...

33 CFR 165.1199 - Security Zones; Military Ocean Terminal Concord (MOTCO), Concord, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Security Zones; Military Ocean... Coast Guard District § 165.1199 Security Zones; Military Ocean Terminal Concord (MOTCO), Concord..., extending from the surface to the sea floor, within 500 yards of the three Military Ocean Terminal Concord...

33 CFR 165.1199 - Security Zones; Military Ocean Terminal Concord (MOTCO), Concord, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Security Zones; Military Ocean... Coast Guard District § 165.1199 Security Zones; Military Ocean Terminal Concord (MOTCO), Concord..., extending from the surface to the sea floor, within 500 yards of the three Military Ocean Terminal Concord...

33 CFR 165.1156 - Safety Zone; Offshore Marine Terminal, El Segundo, CA.

Code of Federal Regulations, 2014 CFR

2014-07-01

... § 165.1156 Safety Zone; Offshore Marine Terminal, El Segundo, CA. (a) Location. The following area is a safety zone: All waters of Santa Monica Bay, from surface to bottom, enclosed by a line beginning at... Terminal, El Segundo, CA. 165.1156 Section 165.1156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

33 CFR 165.1156 - Safety Zone; Offshore Marine Terminal, El Segundo, CA.

Code of Federal Regulations, 2013 CFR

2013-07-01

... § 165.1156 Safety Zone; Offshore Marine Terminal, El Segundo, CA. (a) Location. The following area is a safety zone: All waters of Santa Monica Bay, from surface to bottom, enclosed by a line beginning at... Terminal, El Segundo, CA. 165.1156 Section 165.1156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

33 CFR 165.1156 - Safety Zone; Offshore Marine Terminal, El Segundo, CA.

Code of Federal Regulations, 2011 CFR

2011-07-01

... § 165.1156 Safety Zone; Offshore Marine Terminal, El Segundo, CA. (a) Location. The following area is a safety zone: All waters of Santa Monica Bay, from surface to bottom, enclosed by a line beginning at... Terminal, El Segundo, CA. 165.1156 Section 165.1156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

33 CFR 165.1156 - Safety Zone; Offshore Marine Terminal, El Segundo, CA.

Code of Federal Regulations, 2012 CFR

2012-07-01

... § 165.1156 Safety Zone; Offshore Marine Terminal, El Segundo, CA. (a) Location. The following area is a safety zone: All waters of Santa Monica Bay, from surface to bottom, enclosed by a line beginning at... Terminal, El Segundo, CA. 165.1156 Section 165.1156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

78 FR 7336 - Safety Zone; Alaska Marine Highway System Port Valdez Ferry Terminal, Port Valdez; Valdez, AK

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

... 1625-AA00 Safety Zone; Alaska Marine Highway System Port Valdez Ferry Terminal, Port Valdez; Valdez, AK... Alaska Marine Highway System (AMHS) Port Valdez Ferry Terminal. The purpose of the safety zone is to... Security Delegation No. 0170.1. A representative of the Alaska Marine Highway System requested that the...

Gas centrifuge purge method

DOEpatents

Theurich, Gordon R.

1976-01-01

1. In a method of separating isotopes in a high speed gas centrifuge wherein a vertically oriented cylindrical rotor bowl is adapted to rotate about its axis within an evacuated chamber, and wherein an annular molecular pump having an intake end and a discharge end encircles the uppermost portion of said rotor bowl, said molecular pump being attached along its periphery in a leak-tight manner to said evacuated chamber, and wherein end cap closure means are affixed to the upper end of said rotor bowl, and a process gas withdrawal and insertion system enters said bowl through said end cap closure means, said evacuated chamber, molecular pump and end cap defining an upper zone at the discharge end of said molecular pump, said evacuated chamber, molecular pump and rotor bowl defining a lower annular zone at the intake end of said molecular pump, a method for removing gases from said upper and lower zones during centrifuge operation with a minimum loss of process gas from said rotor bowl, comprising, in combination: continuously measuring the pressure in said upper zone, pumping gas from said lower zone from the time the pressure in said upper zone equals a first preselected value until the pressure in said upper zone is equal to a second preselected value, said first preselected value being greater than said second preselected value, and continuously pumping gas from said upper zone from the time the pressure in said upper zone equals a third preselected value until the pressure in said upper zone is equal to a fourth preselected value, said third preselected value being greater than said first, second and fourth preselected values.

3D seismic reflection imaging of nearly amagmatic oceanic lithosphere at the ultra-slow spreading Southwest Indian Ridge

NASA Astrophysics Data System (ADS)

Momoh, E. I.; Cannat, M.; Singh, S. C.; Watremez, L.; Leroy, S. D.

2016-12-01

Ultra-slow spreading ridges (< 10 mm/yr half-spreading rate), are characterized by a variety of mode accretion, from purely magmatic to nearly amagmatic. With the prevalence of mantle-derived peridotites and sparse volcanism on the seafloor, the easternmost portion of the ultra-slow spreading Southwest Indian Ridge (SWIR) at 64°E represents a melt-poor end-member in the global ridge system. Mantle-derived peridotites there are proposed to have been exhumed along the footwall of detachment faults (Cannat et al, 2006; Sauter et al, 2013). However, the geometry and structural styles of detachments at depth are conjectural. We show the first 3D seismic reflection images of nearly amagmatic axial oceanic lithosphere in this region. The results are from 3D processing of 2D seismic data acquired during the SISMOSMOOTH 2014 cruise along 100 m-spaced profiles in a 1.8 km wide by 24 km long box spanning the axial valley and a part of its elevated northern wall. Wide-angle tomography results from Ocean bottom Seismometer (OBS) line are used to provide a velocity structure of the crust and correlate the MCS reflection images. We image 4 classes of reflectors. The first class occurs in 2 parts as south-dipping events and can be followed in the cross-line of the survey area. The upper part terminates on the northern slope of the massif. The lower part occurs as an isolated event until half of the width of the survey area after which it appears as a continuation of the upper part. This class of reflectors may be due to the damage zone of the active axial detachment fault. The second class of reflectors occurs as north-dipping events. They extend 1 km in the cross-line. They can be interpreted as fractured zones, zones of localized serpentinization or as dikes. The third class of reflectors occurs as sub-horizontal events at depth and seems to serve as the termination of the proposed dikes/fractured zones. On the OBS result, this reflector mimics the 7.5 km/s velocity contour in some areas and < 0.5 s TWT. It is unclear if the depths are coincident. The fourth class of reflectors occurs as shallow intra-crustal reflectors 0.2 - 1 s TWT below the seafloor which does not maintain a consistent character across the survey area. We envisage that they may be associated with zones of localized serpentinization, intrusive melt or fractured zones in the axial valley.

Cadaveric Assessment of Lip Injections: Locating the Serious Threats.

PubMed

Tansatit, Tanvaa; Apinuntrum, Prawit; Phetudom, Thavorn

2017-04-01

Lip augmentation could be a possible cause of blindness following filler injections. This study evaluated the risk by simulating clinical scenarios of marginal injections to the upper and lower lips and then evaluated the risk of vascular injuries. A 22G cannula was inserted bilaterally along the wet-dry junction of the upper and lower lip margins in fifteen cadavers, and then both lips were dissected to verify possible injuries to the superior and inferior labial arteries. The position of the labial arteries in the vermilion zone was documented to determine the appropriate injection technique. In the marginal injections to the lips, arterial injuries occurred at the medial segment of the vermilion zone of both the upper and lower lips, at the terminal part of the labial arteries or a distal branch. Considering arterial anatomy, the upper lip has a higher chance of arterial injury than the lower lip. The cannula should not be inserted in the submucosa as it is recommended to evert the vermilion because both the superior and inferior labial arteries are located in the submucosa of the medial and middle segments of the vermilion in all specimens. Awareness of the possibility of vascular injury is necessary during injections of the medial segments of the vermilion of the lips. Vermilion border and marginal injections are recommended for safe and effective lip augmentation. Deep injection around the oral commissure and submucosal injection of the medial and middle segments of the vermilion zone are prohibited because of the high risk of arterial injury. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Architecture of the Distal Piedmont-Ligurian Rifted Margin in NW Italy: Hints for a Flip of the Rift System Polarity

NASA Astrophysics Data System (ADS)

Decarlis, Alessandro; Beltrando, Marco; Manatschal, Gianreto; Ferrando, Simona; Carosi, Rodolfo

2017-11-01

The Alpine Tethys rifted margins were generated by a Mesozoic polyphase magma-poor rifting leading to the opening of the Piedmont-Ligurian "Ocean." This latter developed through different phases of rifting that terminated with the exhumation of subcontinental mantle along an extensional detachment system. At the onset of simple shear detachment faulting, two margin types were generated: an upper and a lower plate corresponding to the hanging wall and footwall of the final detachment system, respectively. The two margin architectures were markedly different and characterized by a specific asymmetry. In this study the detailed analysis of the Adriatic margin, exposed in the Serie dei Laghi, Ivrea-Verbano, and Canavese Zone, enabled to recognize the diagnostic elements of an upper plate rifted margin. This thesis contrasts with the classic interpretation of the Southalpine units, previously compared with the adjacent fossil margin preserved in the Austroalpine nappes and considered as part of a lower plate. The proposed scenario suggests the segmentation and flip of the Alpine rifting system along strike and the passage from a lower to an upper plate. Following this interpretation, the European and Southern Adria margins are coevally developed upper plate margins, respectively resting NE and SW of a major transform zone that accommodates a flip in the polarity of the rift system. This new explanation has important implications for the study of the pre-Alpine rift-related structures, for the comprehension of their role during the reactivation of the margin and for the paleogeographic evolution of the Alpine orogen.

Terminal zone glacial sediment transfer at a temperate overdeepened glacier system

NASA Astrophysics Data System (ADS)

Swift, D. A.; Cook, S. J.; Graham, D. J.; Midgley, N. G.; Fallick, A. E.; Storrar, R.; Toubes Rodrigo, M.; Evans, D. J. A.

2018-01-01

Continuity of sediment transfer through glacial systems is essential to maintain subglacial bedrock erosion, yet transfer at temperate glaciers with overdeepened beds, where subglacial fluvial sediment transport should be greatly limited by adverse slopes, remains poorly understood. Complex multiple transfer processes in temperate overdeepened systems has been indicated by the presence of large frontal moraine systems, supraglacial debris of mixed transport origin, thick basal ice sequences, and englacial thrusts and eskers. At Svínafellsjökull, thrusts comprising decimetre-thick debris-rich bands of stratified facies ice of basal origin, with a coarser size distribution and higher clast content than that observed in basal ice layers, contribute substantially to the transfer of subglacial material in the terminal zone. Entrainment and transfer of material occurs by simple shear along the upper surface of bands and by strain-induced deformation of stratified and firnified glacier ice below. Thrust material includes rounded and well-rounded clasts that are also striated, indicating that fluvial bedload is deposited as subglacial channels approach the overdeepening and then entrained along thrusts. Substantial transfer also occurs within basal ice, with facies type and debris content dependent on the hydrological connectedness of the adverse slope. A process model of transfer at glaciers with terminal overdeepenings is proposed, in which the geometry of the overdeepening influences spatial patterns of ice deformation, hydrology, and basal ice formation. We conclude that the significance of thrusting in maintaining sediment transfer continuity has likely been overlooked by glacier sediment budgets and glacial landscape evolution studies.

Imaging the Alaskan subduction zone with joint inversion of ambient noise and teleseismic surface waves

NASA Astrophysics Data System (ADS)

Martin-Short, R.; Allen, R. M.; Porritt, R.

2017-12-01

Alaska consists of a complex arrangement of terranes of various geological affinities, mostof which have been accreted to the margin of North America over the last 200Myr. Today,the southern margin of Alaska is a site of active subduction, displaying a myriad ofenigmatic tectonic features. These include transition from compressional to strike-slipdominated deformation, accretion of the over-thickened Yakutat terrane, termination ofAleutian arc magnetism and the Wrangell Volcanic Field, whose magma source remainsdebated. The ongoing deployment of Transportable Array (TA) seismometers across Alaskaprovides an unprecedented opportunity to image these features in detail and learn moreabout the tectonic history of the region. Here we present a three dimensional model ofshear wave (Vsv) velocity beneath Alaska constructed using joint inversion of phasevelocity maps derived from ambient noise and teleseismic surface wave tomography. Thismodel possesses good resolution from the upper crust to about 150km depth, thuscomplementing recent body wave models of the region, which lack resolution above 100km.In the upper crust, we are able to distinguish major sedimentary basins and the cores ofmountain belts. At mid-crustal depths, we see a sharp velocity contrast across the Denalifault, suggesting that it marks a significant step in crustal thickness. In the mantle wedgeabove the subducting Yakutat terrane we observe a high velocity anomaly that may berelated to paucity of volcanism in this region. At greater depths, we image the subductingPacific-Yakutat slab as an elongate, high velocity anomaly that terminates abruptly at 145ºW, slightly further east than suggested by the Wadati-Benioff zone alone. There is alarge, low velocity anomaly beneath the Wrangell Volcanic Field, hinting that magmatismhere may be related to mantle upwelling around the slab edge.

Vertical oxygen minimum zone oscillations since 20 ka in Santa Barbara Basin: A benthic foraminiferal community perspective

NASA Astrophysics Data System (ADS)

Moffitt, Sarah E.; Hill, Tessa M.; Ohkushi, Kenichi; Kennett, James P.; Behl, Richard J.

2014-01-01

we present a history of deoxygenation of upper intermediate waters during the last deglaciation from Santa Barbara Basin (SBB), based on quantitative analyses of benthic foraminiferal assemblages, from a new shallow piston core above basin sill depth (MV0811-15JC, 418 m), and previously described sequences in the deeper basin (MD02-2504, 481 m and MD02-2503, 570 m). We document a 152 m depth transect of benthic foraminiferal assemblages to extract changing community structure (density, diversity, and evenness) and improve paleoenvironmental interpretation of late Quaternary vertical oscillations in the upper boundary of the oxygen minimum zone (OMZ). Close interaction between changes in open margin OMZ and that of the restricted SBB is documented using these quantitative techniques. MV0811-15JC, while being unlaminated, contains strongly hypoxic foraminiferal assemblages (including species Bolivina tumida and Nonionella stella), coeval with preserved sediment laminations in the deeper cores. Last Glacial Maximum (LGM) assemblages across this transect contained oxic fauna and high diversity. At 14.7 ka, glacial termination IA, hypoxic benthic fauna appeared across the transect, recording hypoxic waters (<0.5 ml L-1) < 300 m from the ocean surface. Bølling/Allerød (B/A) assemblages uniquely stand out in the record, exhibited by low density, diversity, and evenness, and taxonomic composition reflecting extreme and stressful hypoxia and methane-rich environments. Younger Dryas assemblages were diverse and composed of oxic fauna, similar to LGM assemblages. Termination IB initiated another deoxygenation shift, followed by OMZ-associated faunal and density patterns. This analysis strengthens the quantitative assessment of oxygen concentrations involved in deglacial OMZ change and reveals the unexpected, remarkable shallowness of OMZ influence during the B/A.

Ground-water quality of the Upper Floridan Aquifer near an abandoned manufactured gas plant in Albany, Georgia

USGS Publications Warehouse

Chapman, M.J.

1993-01-01

Manufactured gas plants produced gas for heating and lighting in the United States from as early as 1816 into the 1960's. By-products including, but not limited to, oil residues and tar, were generated during the gas-manufacturing process. Organic compounds (hydrocarbons) were detected in water in the upper water-bearing zone of the Upper Floridan aquifer near an abandoned manufactured gas plant (MGP) in Albany, Georgia, during an earlier investigation in 1990. Chemical analyses of ground-water samples collected from five existing monitoring wells in 1991 verify the presence of hydrocarbons and metals in the upper water-beating zone of the Upper Floridan aquifer. One well was drilled into the lower water-beating zone of the Upper Floridan aquifer in 1991 for water-quality sampling and water-level monitoring. Analyses of ground water sampled from this well did not show evidence of benzene, toluene, xylene, napthalene, acenaphthlene, or other related compounds detected in the upper water-bearing zone in the study area. Low concentrations of tetrachloroethane, trichloromethane, and l,2-cisdichloroethene were detected in a water sample from the deeper well; however, these compounds were not detected in the upper water-bearing zone in the study area. Inorganic constituent concentrations also were substantially lower in the deeper well. Overall, ground water sampled from the lower water-bearing zone had lower specific conductance and alkalinity; and lower concentrations of dissolved solids, iron, and manganese compared to ground water sampled from the upper water-bearing zone. Water levels for the upper and lower water-bearing zones were similar throughout the study period.

DETAIL VIEW OF WINCHING ENGINE LOCATED AT THE UPPER TRAM ...

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

DETAIL VIEW OF WINCHING ENGINE LOCATED AT THE UPPER TRAM TERMINAL, LOOKING NORTHEAST. THE CABLE FROM THIS ENGINE LEADS DOWN INTO THE DEEP RAVINE IN FRONT OF THE UPPER TRAM TERMINAL. IT WAS PROBABLY USED TO DRAG MATERIALS UP TOWARD THE TERMINAL WHEN THE TERMINAL WAS BEING CONSTRUCTED, OR IN TIMES OF TRAMWAY BREAKDOWN. THE DRIVE ENGINE IS IN THE BACKGROUND. TWO LONG OPERATING LEVERS FOR THE ENGINE ARE IN THE CENTER FOREGROUND. AN EXTRA SPOOL OF CABLE IS ON THE GROUND TO THE RIGHT OF THE ENGINE. A WATER PIPELINE STRETCHES ACROSS THE SLOPE IN THE BACKGROUND, CARRYING WATER TO THE UPPER MINES. SEE CA-291-37 FOR IDENTICAL B&W NEGATIVE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

DETAIL VIEW OF WINCHING ENGINE LOCATED AT THE UPPER TRAM ...

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

DETAIL VIEW OF WINCHING ENGINE LOCATED AT THE UPPER TRAM TERMINAL LOOKING NORTHEAST. THE CABLE FROM THIS ENGINE LEADS DOWN INTO THE DEEP RAVINE IN FRONT OF THE UPPER TRAM TERMINAL. IT WAS PROBABLY USED TO DRAG MATERIALS UP TOWARD THE TERMINAL WHEN THE TERMINAL WAS BEING CONSTRUCTED, OR IN TIMES OF TRAMWAY BREAK DOWN. THE DRIVE ENGINE IS IN THE BACKGROUND. TWO LONG OPERATING LEVERS FOR THE ENGINE ARE IN THE CENTER FOREGROUND. AN EXTRA SPOOL OF CABLE IS ON THE GROUND TO THE RIGHT OF THE ENGINE. A WATER PIPELINE STRETCHES ACROSS THE SLOPE IN THE BACKGROUND, CARRYING WATER TO THE UPPER MINES. SEE CA-291-52 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

33 CFR 165.1710 - Port Valdez and Valdez Narrows, Valdez, Alaska-security zones.

Code of Federal Regulations, 2010 CFR

2010-07-01

... following areas are security zones: (1) Trans-Alaska Pipeline (TAPS) Valdez Terminal complex (Terminal), Valdez, Alaska and TAPS tank vessels. All waters enclosed within a line beginning on the southern... TAPS tank vessel maneuvering to approach, moor, unmoor or depart the TAPS Terminal or transiting...

The Western Tauern Window (Eastern Alps): Timing and Interplay of Folds and Sinistral Shear Zones as Result of South-Alpine Indentation

NASA Astrophysics Data System (ADS)

Schneider, Susanne; Rosenberg, Claudio; Hammerschmidt, Konrad

2010-05-01

The Tauern Window (TW) is the only domain within the Eastern Alps where deep crustal, Tertiary metamorphic rocks were exhumed to surface. The window is bounded by large-scale faults, partly considered to be responsible for its exhumation (e.g., Selverstone 1988, Fügenschuh 1997), and it is also cross cut internally by large-scale shear zones, whose significance in terms of type and timing of deformation, exhumation, and large-scale kinematic links is the subject of our investigation. These shear zones (Ahorn, Olperer, Greiner, Ahrntal) are widespread throughout the western TW, from the mm- to the km-scale. They are sinistral and located in the steep limbs of upright antiforms, forming a mylonitic foliation, that strikes parallel to the axial planes of these upright folds. We present new structural and geochronological data, obtained by in-situ dating of microstructurally defined syn- and postkinematic grains, to constrain the duration and termination of folding and sinistral shearing. Previous dating suggested initiation of shearing contemporaneous to nappe stacking between 32-and 30Ma, ongoing until 15Ma (Glodny et al., 2008). However, the fabric of the dated grains was not related to deformation phases defined from structural overprinting relationships, and the classical separation technique did not allow to separate synkinematic from pre- and post- kinematic grains. The northern margin of the western TW is pervasively overprinted by the Ahorn Shear Zone (Rosenberg & Schneider 2008), which shows S-side up kinematic indicators in addition to the sinistral ones, and a pronounced southward increase in metamorphic grade from lower greenschist facies to amphibolite facies conditions, within 2km. Phengites of the mylonitic foliation dated with the Rb/Sr in-situ technique, yield formation ages of 14-24Ma . The southern margin of the western TW is overprinted by the sinistral Ahrntal Fault (Schneider et al. 2009), which cuts discordantly several nappes from the Zentralgneiss to the Upper Austroalpine units. Within the Upper Penninic nappes N-side up kinematic indicators occur, in addition to the sinistral ones. Newly formed biotites of Zentralgneiss rocks have been dated with the Rb/Sr technique (Kitzig et al. 2009), yielding 18-20Ma for their formation during sinistral deformation. Fine-grained phengites from the axial plane foliation of the upright folds were dated with the K/Ar method, yielding 14-17Ma. Ar/Ar in-situ LA analyses of sinistral mylonites (Ahorn, Olperer and Greiner) yield formation ages of syn-kinematic phengites between 24-12Ma. These grains are overgrown by post-kinematic phengites of 12-9Ma. Northeast of the western TW, sinistral shear is accommodated by the brittle sinistral SEMP Fault system, whose activity has been dated to 17Ma (Peresson & Decker 1997). Several sinistral shear zones (Ahorn, Greiner, Ahrntal) of the western TW may coalesce into the SEMP Fault (e.g., Linzer et al., 2002). In the west, the Ahorn Shear Zone terminates nearly 10km east of the Brenner Fault, into a NW-striking fold belt. The Ahrntal Fault continues into the Jaufen Fault, which merges with the brittle sinistral Giudicarie Fault. Motion along the Giudicarie Fault initiated in the Miocene (Stipp et al., 2004), or already in the Oligocene (Müller et al 2001). Based on these results, a temporal, kinematic and geometric continuity between sinistral shearing along the Giudicarie Fault, along the SEMP Fault, and throughout the western TW, can be assessed. The sinistral shear zones of the western TW are kinematically linked to upright folds, hence to crustal thickening. Upright folding and sinistral shearing were active since 24Ma and terminated at 12Ma. In summary, the sinistral displacements of the Giudicarie System appear to be partitioned into upright folds and sinistral, transpressive shear zones in the western Tauern Window, both of which contribute to its exhumation. The coalescence of the sinistral shear zones into the SEMP Fault System coincides with the eastern termination of the ENE-striking upright folds, possibly indicating transfer of shortening into a strike-slip displacement. Therefore, the western TW as a whole, represents a Miocene, sinistral transpressive belt, accommodating sinistral displacements associated with South-Alpine indentation by folding and sinistral shearing, and transferring these into sinistral movements associated with lateral escape along the SEMP System, until 12 Ma.

Paleoceanographic insights on recent oxygen minimum zone expansion: lessons for modern oceanography.

PubMed

Moffitt, Sarah E; Moffitt, Russell A; Sauthoff, Wilson; Davis, Catherine V; Hewett, Kathryn; Hill, Tessa M

2015-01-01

Climate-driven Oxygen Minimum Zone (OMZ) expansions in the geologic record provide an opportunity to characterize the spatial and temporal scales of OMZ change. Here we investigate OMZ expansion through the global-scale warming event of the most recent deglaciation (18-11 ka), an event with clear relevance to understanding modern anthropogenic climate change. Deglacial marine sediment records were compiled to quantify the vertical extent, intensity, surface area and volume impingements of hypoxic waters upon continental margins. By integrating sediment records (183-2,309 meters below sea level; mbsl) containing one or more geochemical, sedimentary or microfossil oxygenation proxies integrated with analyses of eustatic sea level rise, we reconstruct the timing, depth and intensity of seafloor hypoxia. The maximum vertical OMZ extent during the deglaciation was variable by region: Subarctic Pacific (~600-2,900 mbsl), California Current (~330-1,500 mbsl), Mexico Margin (~330-830 mbsl), and the Humboldt Current and Equatorial Pacific (~110-3,100 mbsl). The timing of OMZ expansion is regionally coherent but not globally synchronous. Subarctic Pacific and California Current continental margins exhibit tight correlation to the oscillations of Northern Hemisphere deglacial events (Termination IA, Bølling-Allerød, Younger Dryas and Termination IB). Southern regions (Mexico Margin and the Equatorial Pacific and Humboldt Current) exhibit hypoxia expansion prior to Termination IA (~14.7 ka), and no regional oxygenation oscillations. Our analyses provide new evidence for the geographically and vertically extensive expansion of OMZs, and the extreme compression of upper-ocean oxygenated ecosystems during the geologically recent deglaciation.

Paleoceanographic Insights on Recent Oxygen Minimum Zone Expansion: Lessons for Modern Oceanography

PubMed Central

Moffitt, Sarah E.; Moffitt, Russell A.; Sauthoff, Wilson; Davis, Catherine V.; Hewett, Kathryn; Hill, Tessa M.

2015-01-01

Climate-driven Oxygen Minimum Zone (OMZ) expansions in the geologic record provide an opportunity to characterize the spatial and temporal scales of OMZ change. Here we investigate OMZ expansion through the global-scale warming event of the most recent deglaciation (18-11 ka), an event with clear relevance to understanding modern anthropogenic climate change. Deglacial marine sediment records were compiled to quantify the vertical extent, intensity, surface area and volume impingements of hypoxic waters upon continental margins. By integrating sediment records (183-2,309 meters below sea level; mbsl) containing one or more geochemical, sedimentary or microfossil oxygenation proxies integrated with analyses of eustatic sea level rise, we reconstruct the timing, depth and intensity of seafloor hypoxia. The maximum vertical OMZ extent during the deglaciation was variable by region: Subarctic Pacific (~600-2,900 mbsl), California Current (~330-1,500 mbsl), Mexico Margin (~330-830 mbsl), and the Humboldt Current and Equatorial Pacific (~110-3,100 mbsl). The timing of OMZ expansion is regionally coherent but not globally synchronous. Subarctic Pacific and California Current continental margins exhibit tight correlation to the oscillations of Northern Hemisphere deglacial events (Termination IA, Bølling-Allerød, Younger Dryas and Termination IB). Southern regions (Mexico Margin and the Equatorial Pacific and Humboldt Current) exhibit hypoxia expansion prior to Termination IA (~14.7 ka), and no regional oxygenation oscillations. Our analyses provide new evidence for the geographically and vertically extensive expansion of OMZs, and the extreme compression of upper-ocean oxygenated ecosystems during the geologically recent deglaciation. PMID:25629508

Capillary zone electrophoresis-mass spectrometer interface

DOEpatents

D`Silva, A.

1996-08-06

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conductors is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer. 1 fig.

Capillary zone electrophoresis-mass spectrometer interface

DOEpatents

D'Silva, Arthur

1996-08-06

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conducts is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer.

Rapid Grain Size Reduction in the Upper Mantle at a Plate Boundary

NASA Astrophysics Data System (ADS)

Kidder, S. B.; Scott, J.; Prior, D. J.; Lubicich, E. J.

2017-12-01

A few spinel peridotite xenoliths found near the Alpine Fault, New Zealand, exhibit a mylonitic texture and, locally, an extremely fine 30 micron grain size. The harzburgite xenoliths were emplaced in a 200 km-long elongate dike zone interpreted as a gigantic tension fracture or Reidel shear associated with Alpine Fault initiation 25 Ma. The presence of thin ( 1 mm) ultramylonite zones with px-ol phase mixing and fine grain sizes, minimal crustal-scale strain associated with the dike swarm, and the absence of mylonites at four of the five xenolith localities associated with the dike swarm indicate that upper mantle deformation was highly localized. Strings of small, recrystallized grains (planes in 3D) are found in the interiors of olivine porphyroclasts. In some cases, bands 1-2 grains thick are traced from the edges of olivine grains and terminate in their interiors. Thicker zones of recrystallized grains are also observed crossing olivine porphyroclasts without apparent offset of the unrecrystallized remnants of the porphyroclasts. We suggest a brittle-plastic origin for these features since the traditional recrystallization mechanisms associated with dislocation creep require much more strain than occurred within these porphyroclasts. Analogous microstructures in quartz and feldspar in mid-crust deformation zones are attributed to brittle-plastic processes. We hypothesize that such fine-grained zones were the precursors of the observed, higher-strain ultramylonite zones. Given the size of the new grains preserved in the porphyroclasts ( 100 micron) and a moho temperature > 650°C, grain growth calculations indicate that the observed brittle-plastic deformation occurred <10,000 yrs. prior to eruption. It is likely then that either brittle-plastic deformation was coeval with the ductile shearing occurring in the ultramylonite bands, or possibly, if deformation can be separated into brittle-plastic (early) and ductile (later) phases, that the entire localization process was very rapid (<10,000 yrs). In either case we interpret that semi-brittle deformation was a key process responsible for rapid localization in this initiating plate-scale mantle shear zone.

Development of a large volume of eruptible mush in the upper Wooley Creek batholith, Klamath Mountains, California: evidence from bulk rock, mineral analyses and textural observations

NASA Astrophysics Data System (ADS)

Coint, N.; Barnes, C. G.; Barnes, M. A.; Yoshinobu, A. S.

2012-12-01

The modalities of development of large volumes of mush in the middle to upper crust capable of erupting have been debated over the past few years. The existence of crystal-rich ignimbrites in the volcanic record indicate that eruptive products do not necessarily correspond to evacuation of the residual magma but that the mush itself can be drained during eruptive events. In this study we present a plutonic example of a large magma batch that evolved by fractional crystallization at a hundred km3 scale: the upper zone of the Wooley Creek batholith (WCb). The WCb is an intrusive complex emplaced over less than 3 m.y. (Kevin Chamberlain, personal communication). The upper zone grades upward from quartz diorite (53 wt% SiO2) to granite (70 wt% SiO2). Hornblende from the central and upper zone have rare earth element patterns that are parallel to one another and with REE concentrations and negative Eu anomalies that decrease from core to rim. The similarities of hornblende REE patterns throughout both the central and upper zones of the system (160 km2 of exposed area) suggest that hornblende crystallized from a magma batch of fairly homogeneous composition. Thus, upward changes in bulk composition between rocks at the bottom and the top of this unit result from varying mineral proportions, with more subhedral plagioclase and hornblende at the bottom and more anhedral to euhedral quartz and interstitial to poikilitic K-feldspar at the top. Two possible explanations are considered: 1) more felsic batches of magma were emplaced at the top of the system and more mafic ones were restricted to the bottom, 2) the upper zone acquired its upward compositional zoning through melt percolation, with the less dense felsic melt ponding at the roof of the system. In the first case, the similarity of hornblende REE patterns throughout the upper zone cannot be explained. Therefore, we favor the second explanation, which is also supported by the lack of sharp contacts in the upper zone. Individual magma batches in the central zone contain hornblende of similar composition as in the upper zone and are interpreted as a preserved part of the feeder system of the latter. Therefore the magma in both the central and upper WCb was already fairly homogeneous when it arrived at the level of emplacement. Dacitic to rhyodacitic roof dikes with30-40% phenocrysts of hornblende and plagioclase with compositions similar to those found in the central and upper zones indicate that the mush was once eruptible. The presence of quartz phenocrysts, which are only found in the uppermost portion of the upper zone, show that 'eruption' occurred after the development of the broad zoning of the upper zone and after more evolved melt had collected at the top of an underlying mush. This study introduces new tools to study magmatic reservoir evolution. The combination of bulk rock and mineral data allows assessment of the extent of mineral-melt separation and identification of the composition of a potential parental magma(s). These data can ideally be used to delimit the size of magma batches and constrain the scale of their chemical/physical connectivity.

33 CFR 165.502 - Safety and Security Zone; Cove Point Liquefied Natural Gas Terminal, Chesapeake Bay, Maryland.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zone; Cove Point Liquefied Natural Gas Terminal, Chesapeake Bay, Maryland. 165.502 Section 165.502 Navigation and... Areas Fifth Coast Guard District § 165.502 Safety and Security Zone; Cove Point Liquefied Natural Gas...

33 CFR 165.502 - Safety and Security Zone; Cove Point Liquefied Natural Gas Terminal, Chesapeake Bay, Maryland.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety and Security Zone; Cove Point Liquefied Natural Gas Terminal, Chesapeake Bay, Maryland. 165.502 Section 165.502 Navigation and... Areas Fifth Coast Guard District § 165.502 Safety and Security Zone; Cove Point Liquefied Natural Gas...

76 FR 47540 - Voluntary Termination of Subzone Status; Chrysler Group, LLC, Newark, DE

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-05

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1775] Voluntary Termination of Subzone Status; Chrysler Group, LLC, Newark, DE Pursuant to its authority under the Foreign-Trade Zones Act of June 18, 1934, as amended (19 U.S.C. 81a-81u), the Foreign-Trade Zones Board (the Board) adopts the...

Iron Isotope Fractionation in the Bushveld Igneous Complex Provide Insight into Fractional Crystallization

NASA Astrophysics Data System (ADS)

Rios, K. L.; Feineman, M. D.; Bybee, G. M.

2016-12-01

Dated at 2.056 Ga and encompassing an estimated 65,000 km2 in surface area and 650,000 km3 in volume the Bushveld Igneous Complex in South Africa contains the largest and most unique layered mafic intrusion in the world. It contains 80-90% of the world's minable platinum group elements. Scientists are interested in understanding the origin of this intrusion due to its massive size, unique assemblage of minerals, and strongly zoned stratigraphy. Iron isotopes may help us to understand the roles of partial mantle melting and fractional crystallization in magma genesis and differentiation. For example, it may be possible to determine what role fractional crystallization of oxides and sulfides played in the formation of the Rustenburg Layered Suite (RLS) by comparing δ56Fe in samples from the Lower, Critical, Main and Upper Zones. The use of MC-ICPMS has made it more routine to study the fractionation of stable iron isotopes in natural systems; however, this technique has only been applied in a few studies of the RLS, mostly restricted to the Upper Main and Upper Zones. In this study δ56Fe was determined in Upper Zone magnetite, Critical Zone chromitite and Critical Zone sulfides using MC-ICP-MS. Previous research has shown that early crystallizing mafic phases incorporate the lighter 54Fe isotope leaving a residual magma with a higher δ56Fe value. Therefore, if the Upper Zone magma represents a high-degree differentiate of the parental Bushveld magma, then magmas from the Upper Zone would be expected to have a higher δ56Fe than magmas contributing to the Lower, Critical and Main Zones. The results of this experiment were indeed consistent with this hypothesis. The δ56Fe values recorded for the three sample types were: magnetite 0.19 ±0.03‰; sulfides -0.45 ±0.03‰ to -0.81 ±0.03‰; and chromitite 0.03 ±0.05‰. The sulfides of the Critical Zone are isotopically lighter than would be predicted based on equilibrium sulfide-melt fractionation, if the parental melt of the Critical Zone were in equilibrium with previously published whole rock data for Upper Zone. This is consistent with interpretations of the Upper Zone as a high degree differentiate of the Bushveld Parental Magma.

Geologic setting, sedimentary architecture, and paragenesis of the Mesoproterozoic sediment-hosted Sheep Creek Cu-Co-Ag deposit, Helena embayment, Montana

USGS Publications Warehouse

Graham, Garth; Hitzman, Murray W.; Zieg, Jerry

2012-01-01

The northern margin of the Helena Embayment contains extensive syngenetic to diagenetic massive pyrite horizons that extend over 25 km along the Volcano Valley-Buttress fault zone and extend up to 8 km basinward (south) within the Mesoproterozoic Newland Formation. The Sheep Creek Cu-Co deposit occurs within a structural block along a bend in the fault system, where replacement-style chalcopyrite mineralization is spatially associated mostly with the two stratigraphically lowest massive pyrite zones. These mineralized pyritic horizons are intercalated with debris flows derived from synsedimentary movement along the Volcano Valley-Buttress fault zone. Cominco American Inc. delineated a geologic resource of 4.5 Mt at 2.5% Cu and 0.1% Co in the upper sulfide zone and 4 Mt at 4% Cu within the lower sulfide zone. More recently, Tintina Resources Inc. has delineated an inferred resource of 8.48 Mt at 2.96% Cu, 0.12% Co, and 16.4 g/t Ag in the upper sulfide zone. The more intact upper sulfide zone displays significant thickness variations along strike thought to represent formation in at least three separate subbasins. The largest accumulation of mineralized sulfide in the upper zone occurs as an N-S–trending body that thickens southward from the generally E trending Volcano Valley Fault and probably occupies a paleograben controlled by normal faults in the hanging wall of the Volcano Valley Fault. Early microcrystalline to framboidal pyrite was accompanied by abundant and local barite deposition in the upper and lower sulfide zones, respectively. The sulfide bodies underwent intense (lower sulfide zone) to localized (upper sulfide zone) recrystallization and overprinting by coarser-grained pyrite and minor marcasite that is intergrown with and replaces dolomite. Silicification and paragenetically late chalcopyrite, along with minor tennantite in the upper sulfide zone, replaces fine-grained pyrite, barite, and carbonate. The restriction of chalcopyrite to inferred synsedimentary E- and northerly trending faults and absence of definitive zonation with respect to the Laramide Volcano Valley Fault in the lower sulfide zone suggest a diagenetic age related to basin development for the Sheep Creek Cu-Co-Ag deposit.

Palynology of late Middle Pennsylvanian coal beds in the Appalachian Basin

USGS Publications Warehouse

Eble, C.F.

2002-01-01

Fossil spores and pollen have long been recognized as valuable tools for identifying and correlating coal beds. This paper describes the palynology of late Middle Pennsylvanian coal beds in the Appalachian Basin with emphasis on forms that assist both intra- and interbasinal coal bed correlation. Stratigraphically important palynomorphs that originate in late Middle Pennsylvanian strata include Torispora securis, Murospora kosankei, Triquitrites minutus, Cadiospora magna, Mooreisporites inusitatus, and Schopfites dimorphus. Taxa that terminate in the late Middle Pennsylvanian include Radiizonates difformis, Densosporites annulatus, Dictyotriletes bireticulatus, Vestispora magna, and Savitrisporites nux. Species of Lycospora, Cirratriradites, Vestispora, and Thymospora, as well as Granasporites medius, Triquitrites sculptilis, and T. securis and their respective ranges slightly higher, in earliest Late Pennsylvanian age strata. Late Middle Pennsylvanian and earliest Late Pennsylvanian strata in the Appalachian Basin correlate with the Radiizonates difformis (RD), Mooreisporites inusitatus (MI), Schopfites colchesterensis-S. dimorphus (CP), and Lycospora granulata-Granasporites medius (GM) spore assemblage zones of the Eastern Interior, or Illinois Basin. In the Western Interior Basin, these strata correlate with the middle-upper portion of the Torispora securis-Laevigatosporites globosus (SG) and lower half of the Thymospora pseudothiessenii-Schopfites dimorphus (PD) assemblage zones. In western Europe, late Middle Pennsylvanian and earliest Late Pennsylvanian strata correlate with the middle-upper portion of the Torispora securis-T. laevigata (SL) and the middle part of the Thymospora obscura-T. thiessenii (OT) spore assemblage zones. Allegheny Formation coal beds also correlate with the Torispora securis (X) and Thymospora obscura (XI) spore assemblages, which were developed for coal beds in Great Britain. ?? 2002 Elsevier Science B.V. All rights reserved.

Hydrogeology of the surficial aquifer in the vicinity of a former landfill, Naval Submarine Base Kings Bay, Camden County, Georgia

USGS Publications Warehouse

Leeth, David C.

1999-01-01

Neogene and Quaternary sediments constitute the surficial aquifer beneath the study area; in descending order from youngest to oldest these include-the Quaternary undifferentiated surficial sand and Satilla Formation; the Pliocene(?) Cypresshead Formation; and the middle Miocene Coosawhatchie Formation. Beneath the surficial aquifer, the upper Brunswick aquifer consists of part of the lower Miocene Marks Head Formation. The surficial aquifer is divided into three water-bearing zones on the basis of lithologic and geophysical properties of sediments, hydraulic-head differences between zones, and differences in ground-water chemistry. The shallowest zone-the water-table zone-consists of medium to fine sand and clayey sand and is present from land surface to a depth of about 77 feet. Below the water-table zone, the confined upper water-bearing zone consists of medium to very coarse sand and is present from a depth of about 110 to 132 feet. Beneath the upper water-bearing zone, the confined lower water-bearing zone consists of coarse sand and very fine gravel and is present from a depth of about 195 to 237 feet. Hydraulic separation is suggested by differences in water chemistry between the water-table zone and upper water-bearing zone. The sodium chloride type water in the water-table zone differs from the calcium bicarbonate type water in the upper water-bearing zone. Hydraulic separation also is indicated by hydraulic head differences of more than 6.5 feet between the water-table zone and the upper water-bearing zone. Continuous and synoptic water-level measurements in the water-table zone, from October 1995 to April 1997, indicate the presence of a water-table high beneath and adjacent to the former landfill-the surface of which varies about 5 feet with time because of recharge and discharge. Water-level data from clustered wells also suggest that restriction of vertical ground-water flow begins to occur at an altitude of about 5 to 10 feet below sea level (35 to 40 feet below land surface) in the water-table zone because of the increasing clay content of the Cypresshead Formation.

Relic magma chamber structures preserved within the Mesozoic North Atlantic crust?

USGS Publications Warehouse

McCarthy, J.; Mutter, J.C.; Morton, J.L.; Sleep, Norman H.; Thompson, G.A.

1988-01-01

The North Atlantic Transect seismic reflection data, collected southwest of Bermuda, have been reinterpreted following post-stack migration and reveal two major intracrustal reflections. The shallower of these two events, located ~1 s below the igneous basement, is a subhorizontal, undulating surface that in some places is continuous for as much as 10 km. This upper crustal reflection corresponds to the intermittently sharp contact between the sheeted dikes and the underlying isotropic gabbro. A second set of lower crustal reflections, dipping ~20??-40?? eastward, is also prominent on the migrated profile and terminates downdip against the subhorizontal reflection Moho. Their presence may be ascribed to mafic-ultramafic cumulate layers frozen into the oceanic crust at the time of formation at the paleo-spreading center. The gradual thinning in the crust approaching the fracture zones is shown to be more complex than was originally inferred. An intepretation advocating crustal thickening in this narrow zone is proposed as an alternative to the crustal-thinning model of Mutter and others. -from Authors

Convectively driven PCR thermal-cycling

DOEpatents

Benett, William J.; Richards, James B.; Milanovich, Fred P.

2003-07-01

A polymerase chain reaction system provides an upper temperature zone and a lower temperature zone in a fluid sample. Channels set up convection cells in the fluid sample and move the fluid sample repeatedly through the upper and lower temperature zone creating thermal cycling.

33 CFR 165.T08-0315 - Safety Zone; Upper Mississippi River, Mile 183.0 to 183.5.

Code of Federal Regulations, 2012 CFR

2012-07-01

... River, Mile 183.0 to 183.5. 165.T08-0315 Section 165.T08-0315 Navigation and Navigable Waters COAST... Guard District § 165.T08-0315 Safety Zone; Upper Mississippi River, Mile 183.0 to 183.5. (a) Location. The following area is a safety zone: All waters of the Upper Mississippi River, mile 183.0 to 183.5...

77 FR 24459 - Voluntary Termination of Foreign-Trade Subzone 9D, Maui Pineapple Company, Ltd., Kahului, Maui, HI

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-24

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1821] Voluntary Termination of Foreign-Trade Subzone 9D, Maui Pineapple Company, Ltd., Kahului, Maui, HI Pursuant to its authority under the Foreign-Trade Zones Act of June 18, 1934, as amended (19 U.S.C. 81a-81u), and the Foreign-Trade Zones...

Structure and Evolution of the Forearc-Arc Crust Along the Tonga-Kermadec Subduction System from Integrated Geophysical Data

NASA Astrophysics Data System (ADS)

Funnell, M.; Peirce, C.; Robinson, A. H.; Watts, A. B.; Grevemeyer, I.

2016-12-01

Variations in tectonic forces and inputs to subduction systems generate, alter, and deform overriding crustal material. Although these processes are recorded in the crustal structure of volcanic arcs and their backarcs, the continuous nature of plate convergence superimposes subsequent episodes of crustal evolution on older features. Seismic imaging at modern subduction zones enhances our understanding of forearc development and variations in present-day deformation caused by inherited structures. In 2011 a set of multichannel and wide-angle seismic profiles imaged the forearc-arc crust and upper mantle structure along the 2700 km-long NNE-SSW trending Tonga-Kermadec subduction zone. The Tonga forearc region exhibits an 100 km-wide, 2 km high bathymetric elevation, with a 3 km-thick upper and mid-crust (Vp <6 km s-1), and a lower-crustal ridge 30 km wide comprising velocities up to 7.4 km s-1 that characterize an extinct Eocene ( 50 Ma) arc. By contrast, the active arc is <10 km wide and exhibits lower-crustal velocities below 7.0 km s-1, most likely representing intermediate compositions. This structural change suggests significant evolution, alteration, and modification of the overriding crust since the onset of subduction at this margin. Gravity anomaly modelling suggests that the extinct arc within the Tonga forearc region comprises relatively dense mafic-ultrabasic material that extends south beneath the Kermadec forearc and terminates at 32°S. The apparent southern termination of the extinct arc coincides with the partitioning of morphological features at 32°S, including a 10-km westward-step of the active arc and a 1.5 km deeper backarc to the south. We propose that tectonic partitioning about the 32°S boundary is the result of variations in the inherited crustal structure, which is divided by the presence and absence, to the north and south respectively, of the extinct volcanic arc.

Propagation of back-arc extension in the arc of the southern New Hebrides Subduction Zone (South West Pacific) and possible relation to subduction initiation.

NASA Astrophysics Data System (ADS)

Fabre, M.; Patriat, M.; Collot, J.; Danyushevsky, L. V.; Meffre, S.; Falloon, T.; Rouillard, P.; Pelletier, B.; Roach, M. J.; Fournier, M.

2015-12-01

Geophysical data acquired during three expeditions of the R/V Southern Surveyor allows us to characterize the deformation of the upper plate at the southern termination of the New Hebrides subduction zone where it bends 90° eastward along the Hunter Ridge. As shown by GPS measurements and earthquake slip vectors systematically orthogonal to the trench, this 90° bend does not mark a transition from subduction to strike slip as usually observed at subduction termination. Here the convergence direction remains continuously orthogonal to the trench notwithstanding its bend. Multibeam bathymetric data acquired in the North Fiji Basin reveals active deformation and fragmentation of the upper plate. It shows the southward propagation of a N-S back-arc spreading ridge into the pre-existing volcanic arc, and the connection of the southern end of the spreading axis with an oblique active rift in the active arc. Ultimately the active arc lithosphere is sheared as spreading progressively supersedes rifting. Consequently to such incursion of back-arc basin extension into the arc, peeled off and drifted pieces of arc crust are progressively isolated into the back-arc basin. Another consequence is that the New Hebrides arc is split in two distinct microplates, which move independently relative to the lower plate, and thereby define two different subduction systems. We suggest arc fragmentation could be a consequence of the incipient collision of the Loyalty Ridge with the New Hebrides Arc. We further speculate that this kinematic change could have resulted, less than two million year ago, in the initiation of a new subduction orthogonal to the New Hebrides Subduction possibly along the paleo STEP fault. In this geodynamic setting, with an oceanic lithosphere subducting beneath a sheared volcanic arc, a particularly wide range of primitive subduction-related magmas have been produced including adakites, island arc tholeiites, back-arc basin basalts, and medium-K subduction-related lavas.

TOP VIEW OF UPPER TRAM TERMINAL, PRIMARY ORE BIN, AND ...

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

TOP VIEW OF UPPER TRAM TERMINAL, PRIMARY ORE BIN, AND ORE CHUTE,LOOKING SOUTHWEST. TRAM MACHINERY AND GEARS ARE AT LOWER CENTER. A SMALL ELECTRIC MOTOR AT THE REAR LEFT OF THE TERMINAL PROBABLY WAS ADDED AFTER THE ORIGINAL CONSTRUCTION. THE MOVING CABLE OF THE TRAM WAS DRIVEN BY THESE GEARS AND THE LARGE WHEEL UNDERNEATH (SEE CA-291-31 FOR DETAIL). EMPTY TRAM BUCKETS CAME IN FROM THE LEFT, SWINGING AROUND TO THE CHUTES FROM THE ORE BIN TO BE LOADED FOR THE TRIP DOWN TO THE MILL (SEE CA-291-35 FOR DETAIL). THE BREAK OVER TOWER CAN BE SEEN IN THE DISTANCE AT TOP LEFT. THE SUPPORT TOWER BETWEEN THE UPPER TERMINAL AND THE BREAK OVER TOWER IS COLLAPSED. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

What electrical measurements can say about changes in fault systems.

PubMed Central

Madden, T R; Mackie, R L

1996-01-01

Earthquake zones in the upper crust are usually more conductive than the surrounding rocks, and electrical geophysical measurements can be used to map these zones. Magnetotelluric (MT) measurements across fault zones that are parallel to the coast and not too far away can also give some important information about the lower crustal zone. This is because the long-period electric currents coming from the ocean gradually leak into the mantle, but the lower crust is usually very resistive and very little leakage takes place. If a lower crustal zone is less resistive it will be a leakage zone, and this can be seen because the MT phase will change as the ocean currents leave the upper crust. The San Andreas Fault is parallel to the ocean boundary and close enough to have a lot of extra ocean currents crossing the zone. The Loma Prieta zone, after the earthquake, showed a lot of ocean electric current leakage, suggesting that the lower crust under the fault zone was much more conductive than normal. It is hard to believe that water, which is responsible for the conductivity, had time to get into the lower crustal zone, so it was probably always there, but not well connected. If this is true, then the poorly connected water would be at a pressure close to the rock pressure, and it may play a role in modifying the fluid pressure in the upper crust fault zone. We also have telluric measurements across the San Andreas Fault near Palmdale from 1979 to 1990, and beginning in 1985 we saw changes in the telluric signals on the fault zone and east of the fault zone compared with the signals west of the fault zone. These measurements were probably seeing a better connection of the lower crust fluids taking place, and this may result in a fluid flow from the lower crust to the upper crust. This could be a factor in changing the strength of the upper crust fault zone. PMID:11607664

Integrated seismic model of the crust and upper mantle of the Trans-European Suture zone between the Precambrian craton and Phanerozoic terranes in Central Europe

NASA Astrophysics Data System (ADS)

Wilde-Piórko, Monika; Świeczak, Marzena; Grad, Marek; Majdański, Mariusz

2010-01-01

The structure and evolution of the Trans-European Suture zone (TESZ), contact between Precambrian Europe to the northeast and Phanerozoic terranes to the southwest is one of the main tectonic questions in Europe. The knowledge of the crustal structure, lithosphere-asthenosphere boundary and mantle transition zone between two seismic discontinuities at depths "410" and "660" km, is one of the most important issues to understand the Earth's dynamics. To create a mantle model of the TESZ and surroundings we used different seismic data collected along the 950 km long POLONAISE'97 profile P4. Previous results of 2-D ray-tracing and P-wave travel time modelling and new results of P-wave travel time residuals methods and receiver function sections provide facts about the seismic structure from the surface down to 900 km depth. In the TESZ a large basin, about 125 km wide, is filled with sedimentary strata (Vp < 6.0 km s - 1 ) to about 20 km depth. This basin is asymmetric with its northeast margin being most abrupt. The crystalline crust under this basin is only about 20 km thick today indicating that the lithosphere of Baltica was either thinned drastically or terminated along the northeast margin of the basin. The East European craton (EEC) has a ~ 45 km thick three-layered crust. The crust of the accreted terranes to the southwest is relatively thin (~ 30 km) and similar to that found in other non-cratonal areas of Western Europe. The lower crust is relatively fast (Vp > 7.0 km s - 1 ) along most of the P4 profile. However, lower values to the southwest may indicate the termination of Baltica. High velocity (~ 8.35 km s - 1 ) uppermost mantle lies beneath the Avalonia/Variscan terranes, and may be due to rifting and/or subduction. The seismic lithosphere thickness for the EEC is about 200 km, while it is only 90 km in the Palaeozoic platform (PP). The mantle transition zone is shallower and about 30 km thicker under the EEC, which could be due to thermal conditions (lower temperature) and/or the presence of water and FeO. The result of this paper is a new compiled and integrated seismic velocity model, available in digital form down to 900 km depth ( http://www.igf.fuw.edu.pl/p4-mantle), which can be used as a preliminary model of the crust and upper mantle in the TESZ area in Central Europe.

77 FR 28255 - Safety Zone; Upper Mississippi River, Mile 183.0 to 183.5

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-14

...-AA00 Safety Zone; Upper Mississippi River, Mile 183.0 to 183.5 AGENCY: Coast Guard, DHS. ACTION... Upper Mississippi River, from mile 183.0 to mile 183.5, in the vicinity of the Merchants Bridge and... Merchants Bridge in the vicinity of mile 183.0 to 183.5 on the Upper Mississippi River. After initial...

78 FR 46258 - Safety Zone; Upper Mississippi River, Mile 662.8 to 663.9

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-31

...-AA00 Safety Zone; Upper Mississippi River, Mile 662.8 to 663.9 AGENCY: Coast Guard, DHS. ACTION... Upper Mississippi River, from mile 662.8 to 663.9, extending the entire width of the river. This safety... mile 662.8 to 663.9 on the Upper Mississippi River. Anticipated traffic on the river presents safety...

76 FR 36316 - Safety Zone; Upper Mississippi River, Mile 180.0 to 179.0

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-22

...-AA00 Safety Zone; Upper Mississippi River, Mile 180.0 to 179.0 AGENCY: Coast Guard, DHS. ACTION... Upper Mississippi River, from Mile 180.0 to 179.0, extending the entire width of the river. This safety... combat capabilities between Mile 180.0 and 179.0 on the Upper Mississippi River. This event presents...

Three Skin Zones in the Asian Upper Eyelid Pertaining to the Asian Blepharoplasty.

PubMed

Choi, Yeop; Kang, Hyun Gu; Nam, Yong Seok

2017-06-01

Natural looking double fold is an essential and aesthetically pleasing masterpiece in Asian blepharoplasty. This study aims to emphasize the 3 skin zone concept in the Asian upper blepharoplasty. The authors examined the anterior lamella of each skin zone microscopically by performing 31 double-eyelid surgeries and 11 infrabrow lifts. Characteristics of dermal components, subcutaneous tissue, and outer fascia of OOM (OFOOM) at each skin zone were documented. The authors evaluated the vertical scales of each skin zone in young and aged Asian patients who visited the first author's clinic for the primary or secondary upper blepharoplasty with ×3.5 magnifying surgical loupe. The thickness of OOM had no difference among zones 1, 2, and 3. The skin and subdermal tissue had varying characteristics according to its skin zone. At zone 1, it seemed that only thin skin was on the OOM. The anterior lamella of zone 2 seemed to consist of skin, white fascia (OFOOM) including a venous network, and OOM in a gross field. At zone 3, thick skin, thick subcutaneous fatty layer, and OOM were magnified. The OFOOM of zone 3 was not significantly identified due to a sticky adherence with OOM. At the point of vertical scales of skin zone, good eyelids have lower zone 3 ratio and higher zones 1 and 2 ratio with qualified topographic condition. The authors classified the Asian upper eyelid as with 3 skin zones. Based on its anatomical investigation, the authors can afford anthropometric data and supplemental theory for the creation of aesthetic folds.

The occurrence of the Complexiopollis-Atlantopollis zone (Palynomorphs) in the Eagle Ford Group (Upper Cretaceous) of Texas

USGS Publications Warehouse

Christopher, Raymond A.

1982-01-01

The Lower and lower Upper Cretaceous palynological zones defined in the Atlantic Coastal Plain Province and which occur in the eastern Gulf Coastal Plain Province are characterized by a paucity of marine invertebrate fossils. As a result, correlation of these zones with European and provincial stages, as well as with other microfossil and megafossil zones is tenuous. However, an examination of a complete section of the Eagle Ford Group and adjacent strata in Texas reveals that: 1) the upper part of the Woodbine Formation and the Tarrant Formation of the overlying Eagle Ford Group represent a biostratigraphic interval that is absent in the Atlantic and eastern Gulf Coastal Plain Provinces; 2) the Complexiopollis-Atlantopollis Zone (zone IV of some authors) occurs within the Britton Formation (Eagle Ford Group), and is equivalent to the upper part of the Rotalipora cushmani-greenhornensis Subzone (planktic foraminifers) and possibly to the Sciponoceras gracile Zone (ammonites); 3) the Arcadia Park Formation (Eagle Ford Group) contains a mixed assemblage of palynomorphs that includes guides to both the Complexiopollis-Atlantopollis and the overlying Complexiopollis exigua-Santalacites minor Zones, suggesting that biostratigraphic equivalents of the Arcadia Park Formation are not represented in the Atlantic and eastern Gulf Coastal Plain Provinces; and 4) in the basal part of the Austin Chalk of Texas, only one guide palynomorph to the Complexiopollis-Atlantopollis Zone was recognized, but guides to the Complexiopollis exigua-Santalacites minor Zone are present. The Tuscaloosa Group of the eastern Gulf Coastal Plain appears to be biostratigraphically equivalent to the Complexiopollis-Atlantopollis Zone, and therefore correlative with the middle to upper part of the Britton Formation of the Eagle Ford Group.

Terminator assembly for a floating structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu, H.; Hall, J.E.

1987-10-20

A terminator assembly is described for use in mooring a floating surface to the floor of a body of water. The floating structure has has an upper support and a lower support, comprising: a hawsepipe extending downwardly from adjacent the upper support and supported by the lower support, a tension member extending downwardly from adjacent the upper support through the hawsepipe and the lower support. The tension member has a lower end adapted for connection to the floor of the body of water. Locking means connected to an upper portion of the tension member for maintaining the tension member inmore » tension by acting upon an upper portion of the hawsepipe without transferring primary tension load forces to the upper support.« less

Hermetically sealed electrical feedthrough for high temperature secondary cells

DOEpatents

Knoedler, R.; Nelson, P.A.; Shimotake, H.; Battles, J.E.

1983-07-26

A passthrough seal is disclosed for electrically isolating the terminal in a lithium/metal sulfide cell from the structural cell housing. The seal has spaced upper and lower insulator rings fitted snuggly between the terminal and an annularly disposed upstanding wall, and outwardly of a powdered insulator also confined between the upstanding wall and terminal. The adjacent surfaces of the upper insulator ring and the respective upstanding wall and terminal are conically tapered, diverging in the axial direction away from the cell interior, and a sealing ring is located between each pair of the adjacent surfaces. The components are sized so that upon appropriate movement of the upper insulator ring toward the lower insulator ring the powdered insulator and sealing rings are each compressed to a high degree. This compacts the powdered insulator thereby rendering the same highly impervious and moreover fuses the sealing rings to and between the adjacent surfaces. The upper and lower insulator rings might be formed of beryllium oxide and/or alumina, the powdered insulator might be formed of boron nitride, and the sealing rings might be formed of aluminum.

Hermetically sealed electrical feedthrough for high temperature secondary cells

DOEpatents

Knoedler, Reinhard; Nelson, Paul A.; Shimotake, Hiroshi; Battles, James E.

1985-01-01

A passthrough seal is disclosed for electrically isolating the terminal in a lithium/metal sulfide cell from the structural cell housing. The seal has spaced upper and lower insulator rings fitted snuggly between the terminal and an annularly disposed upstanding wall, and outwardly of a powdered insulator also confined between the upstanding wall and terminal. The adjacent surfaces of the upper insulator ring and the respective upstanding wall and terminal are conically tapered, diverging in the axial direction away from the cell interior, and a sealing ring is located between each pair of the adjacent surfaces. The components are sized so that upon appropriate movement of the upper insulator ring toward the lower insulator ring the powdered insulator and sealing rings are each compressed to a high degree. This compacts the powdered insulator thereby rendering the same highly impervious and moreover fuses the sealing rings to and between the adjacent surfaces. The upper and lower insulator rings might be formed of beryllium oxide and/or alumina, the powdered insulator might be formed of boron nitride, and the sealing rings might be formed of aluminum.

76 FR 77901 - Safety Zone; Upper Mississippi River, Mile 389.4 to 403.1

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-15

...-AA00 Safety Zone; Upper Mississippi River, Mile 389.4 to 403.1 AGENCY: Coast Guard, DHS. ACTION... Upper Mississippi River, from Mile 389.4 to 403.1, extending the entire width of the river located on... 389.4 to 403.1 on the Upper Mississippi River. Under 5 U.S.C. 553(d)(3), the Coast Guard finds that...

A revision of the Norian Conchostracan Zonation in North America and its implications for Late Triassic North American tectonic history

USGS Publications Warehouse

Weems, Robert E.; Lucas, Spencer G.

2015-01-01

Collections of Upper Triassic (Norian) conchostracans from the upper Cumnock and lower Sanford formations (North Carolina), Bull Run Formation (Virginia), Gettysburg Formation (Pennsylvania), Passaic Formation (New Jersey), Blomidon Formation (Nova Scotia), and Redonda Formation (New Mexico) have significantly expanded our knowledge of the Norian conchostracan faunas in these units. These collections show that the temporal and spatial distribution of Norian conchostracans in North America is more complex and more environmentally controlled than previously thought. The new collections require a revision and simplification of the published conchostracan zonation for this interval. The revised zonation, based almost entirely on evolution within the lineage of the conchostracan genus Shipingia, consists of five zones: the Shipingia weemsi-Euestheria buravasi zone (Lacian), the Shipingia mcdonaldi zone (lower Alaunian), the Shipingia hebaozhaiensis zone (upper Alaunian), the Shipingia olseni zone (lower and middle Sevatian), and the Shipingia gerbachmanni zone (upper Sevatian). A new species of Norian conchostracan, Wannerestheria kozuri, is described from the Groveton Member of the Bull Run Formation (Virginia). Two new members (Plum Run and Fairfield members) are named in the Gettysburg Formation (Gettysburg Basin, Maryland and Pennsylvania). The distribution of upper Carnian and Norian strata in the Fundy, Newark, Gettysburg, and Culpeper basins indicates that there was a significant, previously undetected tectonic reorganization within these basins that occurred around the Carnian-Norian boundary. The presence of an upper Norian-lower Rhaetian unconformity within the Newark Supergroup is reaffirmed. A re-evaluation of the conchostracan record from the Redonda Formation of the Chinle Group in New Mexico indicates that the four conchostracan-bearing lacustrine beds in this unit are part of only a single, consistently recognizable conchostracan zone, which we here designate as the Shipingia gerbachmanni zone.

Modification of the ionosphere near the terminator due to the passage of a strong tropical cyclone through the large Island

NASA Astrophysics Data System (ADS)

Belyaev, G.; Boychev, B.; Kostin, V.; Trushkina, E.; Ovcharenko, O.

2015-03-01

Earlier by the authors according to the Intercosmos Bulgaria-1300 and Cosmos-1809 satellite data it's been shown that the ionosphere is modified above the tropical cyclones (TC). Local perturbations of the plasma density, the appearance of the electric fields and the development of ELF-VLF zone of turbulence were observed. These effects were due to the injection of up stream of neutral particles from TC. In this paper the data of the Cosmos-1809 satellite when tropical cyclone Harry (1989) passed through the island of New Caledonia was examined. Influence of evening and morning terminators on the structure of the ionosphere from TC was discussed. It is detected: 1 - the appearance of latitude belt (up to 5000km) of structured perturbations in the night ionosphere; 2 - simulation in the illuminated ionosphere of periodic oscillation of the electric field with a scale ~ 400 km, passing beyond plasma pause. Model for the formation above TC in the lower ionosphere vertical submerged jet that injects neutral particles of different varieties into the upper ionosphere on ballistic trajectories was proposed. Changing of the ionization of neutral particles near the terminator and the deviation of the jet under the interaction of the TC with the island are confirmed in the proposed model.

Meteoric calcite cementation: diagenetic response to relative fall in sea-level and effect on porosity and permeability, Las Negras area, southeastern Spain

NASA Astrophysics Data System (ADS)

Li, Zhaoqi; Goldstein, Robert H.; Franseen, Evan K.

2017-03-01

A dolomitized Upper Miocene carbonate system in southeast Spain contains extensive upper and lower zones of calcite cementation that cut across the stratigraphy. Cement textures including isopachous and circumgranular, which are consistent with phreatic-zone cementation. Cements in the upper cemented zone are non-luminescent, whereas those in the lower cemented zone exhibit multiple bands of luminescent and non-luminescent cements. In the upper cemented zone, isotopic data show two meteoric calcite lines (MCL) with mean δ18O at - 5.1‰ and - 5.8‰ VPDB, whereas no clear MCL is defined in the lower cemented zone where mean δ18O for calcite cement is at - 6.7‰ VPDB. δ13C values in both cement zones are predominantly negative, ranging from - 10 to + 2‰ VPDB, suggestive of carbon from soil gas or decayed organics. Measurements of Tm ice in primary fluid inclusions yield a mode of 0.0 °C in both zones, indicating calcite cementation from fresh water. These two zones define the positions of two different paleo-water tables that formed during a relative sea-level fall and erosional downcutting during the Plio-Pleistocene. The upper cemented zone pre-dated the lower cemented zone on the basis of known relative sea-level history. Meteoric calcite cementation reduced porosity and permeability, but measured values are inconsistent with simple filling of open pore space. Each texture, boundstone, grainstone, packstone, wackestone, produces a different relationship between percent calcite cement and porosity/permeability. Distribution of cements may be predictable on the basis of known sea-level history, and the effect of the cementation can be incorporated into subsurface geomodels by defining surfaces of rock boundaries that separate cemented zones from uncemented zones, and applying texture-specific relationships among cementation, porosity and permeability.

Study on 3-D velocity structure of crust and upper mantle in Sichuan-yunnan region, China

USGS Publications Warehouse

Wang, C.; Mooney, W.D.; Wang, X.; Wu, J.; Lou, H.; Wang, F.

2002-01-01

Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others appear the characteristic of tectonic boundary, indicating that the faults litely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the Sichuan-Yunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the Indian and the Asian plates. The crustal velocity in the Sichuan-Yunnan rhombic block generally shows normal.value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below.

Rayleigh and S wave tomography constraints on subduction termination and lithospheric foundering in central California

USGS Publications Warehouse

Jiang, Chengxin; Schmandt, Brandon; Hansen, Steven M.; Dougherty, Sara L.; Clayton, Robert W.; Farrell, Jamie; Lin, Fan-Chi

2018-01-01

The crust and upper mantle structure of central California have been modified by subduction termination, growth of the San Andreas plate boundary fault system, and small-scale upper mantle convection since the early Miocene. Here we investigate the contributions of these processes to the creation of the Isabella Anomaly, which is a high seismic velocity volume in the upper mantle. There are two types of hypotheses for its origin. One is that it is the foundered mafic lower crust and mantle lithosphere of the southern Sierra Nevada batholith. The alternative suggests that it is a fossil slab connected to the Monterey microplate. A dense broadband seismic transect was deployed from the coast to the western Sierra Nevada to fill in the least sampled areas above the Isabella Anomaly, and regional-scale Rayleigh and S wave tomography are used to evaluate the two hypotheses. New shear velocity (Vs) tomography images a high-velocity anomaly beneath coastal California that is sub-horizontal at depths of ∼40–80 km. East of the San Andreas Fault a continuous extension of the high-velocity anomaly dips east and is located beneath the Sierra Nevada at ∼150–200 km depth. The western position of the Isabella Anomaly in the uppermost mantle is inconsistent with earlier interpretations that the Isabella Anomaly is connected to actively foundering foothills lower crust. Based on the new Vs images, we interpret that the Isabella Anomaly is not the dense destabilized root of the Sierra Nevada, but rather a remnant of Miocene subduction termination that is translating north beneath the central San Andreas Fault. Our results support the occurrence of localized lithospheric foundering beneath the high elevation eastern Sierra Nevada, where we find a lower crustal low Vs layer consistent with a small amount of partial melt. The high elevations relative to crust thickness and lower crustal low Vs zone are consistent with geological inferences that lithospheric foundering drove uplift and a ∼3–4 Ma pulse of basaltic magmatism.

Rayleigh and S wave tomography constraints on subduction termination and lithospheric foundering in central California

NASA Astrophysics Data System (ADS)

Jiang, Chengxin; Schmandt, Brandon; Hansen, Steven M.; Dougherty, Sara L.; Clayton, Robert W.; Farrell, Jamie; Lin, Fan-Chi

2018-04-01

The crust and upper mantle structure of central California have been modified by subduction termination, growth of the San Andreas plate boundary fault system, and small-scale upper mantle convection since the early Miocene. Here we investigate the contributions of these processes to the creation of the Isabella Anomaly, which is a high seismic velocity volume in the upper mantle. There are two types of hypotheses for its origin. One is that it is the foundered mafic lower crust and mantle lithosphere of the southern Sierra Nevada batholith. The alternative suggests that it is a fossil slab connected to the Monterey microplate. A dense broadband seismic transect was deployed from the coast to the western Sierra Nevada to fill in the least sampled areas above the Isabella Anomaly, and regional-scale Rayleigh and S wave tomography are used to evaluate the two hypotheses. New shear velocity (Vs) tomography images a high-velocity anomaly beneath coastal California that is sub-horizontal at depths of ∼40-80 km. East of the San Andreas Fault a continuous extension of the high-velocity anomaly dips east and is located beneath the Sierra Nevada at ∼150-200 km depth. The western position of the Isabella Anomaly in the uppermost mantle is inconsistent with earlier interpretations that the Isabella Anomaly is connected to actively foundering foothills lower crust. Based on the new Vs images, we interpret that the Isabella Anomaly is not the dense destabilized root of the Sierra Nevada, but rather a remnant of Miocene subduction termination that is translating north beneath the central San Andreas Fault. Our results support the occurrence of localized lithospheric foundering beneath the high elevation eastern Sierra Nevada, where we find a lower crustal low Vs layer consistent with a small amount of partial melt. The high elevations relative to crust thickness and lower crustal low Vs zone are consistent with geological inferences that lithospheric foundering drove uplift and a ∼3-4 Ma pulse of basaltic magmatism.

Three-dimensional analysis of vestibular efferent neurons innervating semicircular canals of the gerbil

NASA Technical Reports Server (NTRS)

Purcell, I. M.; Perachio, A. A.

1997-01-01

Anterograde labeling techniques were used to examine peripheral innervation patterns of vestibular efferent neurons in the crista ampullares of the gerbil. Vestibular efferent neurons were labeled by extracellular injections of biocytin or biotinylated dextran amine into the contralateral or ipsilateral dorsal subgroup of efferent cell bodies (group e) located dorsolateral to the facial nerve genu. Anterogradely labeled efferent terminal field varicosities consist mainly of boutons en passant with fewer of the terminal type. The bouton swellings are located predominately in apposition to the basolateral borders of the afferent calyces and type II hair cells, but several boutons were identified close to the hair cell apical border on both types. Three-dimensional reconstruction and morphological analysis of the terminal fields from these cells located in the sensory neuroepithelium of the anterior, horizontal, and posterior cristae were performed. We show that efferent neurons densely innervate each end organ in widespread terminal fields. Subepithelial bifurcations of parent axons were minimal, with extensive collateralization occurring after the axons penetrated the basement membrane of the neuroepithelium. Axonal branching ranged between the 6th and 27th orders and terminal field collecting area far exceeds that of the peripheral terminals of primary afferent neurons. The terminal fields of the efferent neurons display three morphologically heterogeneous types: central, peripheral, and planum. All cell types possess terminal fields displaying a high degree of anisotropy with orientations typically parallel to or within +/-45 degrees of the longitudinal axis if the crista. Terminal fields of the central and planum zones predominately project medially toward the transverse axis from the more laterally located penetration of the basement membrane by the parent axon. Peripheral zone terminal fields extend predominately toward the planum semilunatum. The innervation areas of efferent terminal fields display a trend from smallest to largest for the central, peripheral, and planum types, respectively. Neurons that innervate the central zone of the crista do not extend into the peripheral or planum regions. Conversely, those neurons with terminal fields in the peripheral or planum regions do not innervate the central zone of the sensory neuroepithelium. The central zone of the crista is innervated preferentially by efferent neurons with cell bodies located in the ipsilateral group e. The peripheral and planum zones of the crista are innervated preferentially by efferent neurons with cell bodies located in the contralateral group e. A model incorporating our anatomic observations is presented describing an ipsilateral closed-loop feedback between ipsilateral efferent neurons and the periphery and an open-loop feed-forward innervation from contralateral efferent neurons. A possible role for the vestibular efferent neurons in the modulation of semicircular canal afferent response dynamics is proposed.

Radial Anisotropy in the Mantle Transition Zone and Its Implications

NASA Astrophysics Data System (ADS)

Chang, S. J.; Ferreira, A. M.

2016-12-01

Seismic anisotropy is a useful tool to investigate mantle flow, mantle convection, and the presence of melts in mantle, since it provides information on the direction of mantle flow or the orientation of melts by combining it with laboratory results in mineral physics. Although the uppermost and lowermost mantle with strong anisotropy have been well studied, anisotropic properties of the mantle transition zone is still enigmatic. We use a recent global radially anisotropic model, SGLOBE-rani, to examine the patterns of radial anisotropy in the mantle transition zone. Strong faster SV velocity anomalies are found in the upper transition zone beneath subduction zones in the western Pacific, which decrease with depth, thereby nearly isotropic in the lower transition zone. This may imply that the origin for the anisotropy is the lattice-preferred orientation of wadsleyite, the dominant anisotropic mineral in the upper transition zone. The water content in the upper transition zone may be inferred from radial anisotropy because of the report that anisotropic intensity depends on the water content in wadsleyite.

Extra- and intramuscular nerve supply of the muscles of the anterior antebrachial compartment: applications for selective neurotomy and for botulinum toxin injection.

PubMed

Lepage, D; Parratte, B; Tatu, L; Vuiller, F; Monnier, G

2005-12-01

Hypertonia of the upper limb due to spasticity causes pronation of the forearm and flexion of wrist and fingers. Nowadays this spasticity is often treated with injections of botulinum toxin and sometimes with selective fascicular neurotomy. To correctly perform this microsurgical technique, it is necessary to get precise knowledge of the extramuscular nerve branching in order to be better able to select the motor branches which supply the muscles involved in spasticity. The same knowledge is required for botulinum toxin injections which must be made as near as possible to the zones where intramuscular nerve endings are the densest, which is also where neuromuscular junctions are the most numerous. Thus, it is necessary to better know these zones, but their knowledge remains today imprecise. The muscles of the anterior compartment of 30 forearms were dissected, first macroscopically, then microscopically, to study the extra- and intramuscular nerve supply and the distribution of terminal nerve ramifications. The results were then linked to surface topographical landmarks to indicate the precise location of motor branches for each muscle with the aim of proposing appropriate surgical approaches for selective neurotomies. Then for each muscle, the zones with the highest density of nerve endings were divided into segments, thus determining the optimal zones for botulinim toxin injections.

77 FR 40518 - Swim Events in the Captain of the Port New York Zone; Hudson River, East River, Upper New York...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-10

... 1625-AA00 Swim Events in the Captain of the Port New York Zone; Hudson River, East River, Upper New York Bay, Lower New York Bay; New York, NY ACTION: Final rule. SUMMARY: The Coast Guard is establishing seven temporary safety zones for swim events within the Captain of the Port (COTP) New York Zone. These...

Replication landscape of the human genome

PubMed Central

Petryk, Nataliya; Kahli, Malik; d'Aubenton-Carafa, Yves; Jaszczyszyn, Yan; Shen, Yimin; Silvain, Maud; Thermes, Claude; Chen, Chun-Long; Hyrien, Olivier

2016-01-01

Despite intense investigation, human replication origins and termini remain elusive. Existing data have shown strong discrepancies. Here we sequenced highly purified Okazaki fragments from two cell types and, for the first time, quantitated replication fork directionality and delineated initiation and termination zones genome-wide. Replication initiates stochastically, primarily within non-transcribed, broad (up to 150 kb) zones that often abut transcribed genes, and terminates dispersively between them. Replication fork progression is significantly co-oriented with the transcription. Initiation and termination zones are frequently contiguous, sometimes separated by regions of unidirectional replication. Initiation zones are enriched in open chromatin and enhancer marks, even when not flanked by genes, and often border ‘topologically associating domains' (TADs). Initiation zones are enriched in origin recognition complex (ORC)-binding sites and better align to origins previously mapped using bubble-trap than λ-exonuclease. This novel panorama of replication reveals how chromatin and transcription modulate the initiation process to create cell-type-specific replication programs. PMID:26751768

78 FR 12716 - Expansion of Foreign-Trade Zone 49 Newark/Elizabeth, New Jersey

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-25

... that would terminate authority on February 28, 2018 for Site 13 if no activity has occurred under FTZ... terminate authority where no activity has occurred under FTZ procedures by February 28, 2018. Signed at... Administration, Alternate Chairman, Foreign-Trade Zones Board. Attest: Andrew McGilvray, Executive Secretary. [FR...

Vitrification of waste with conitnuous filling and sequential melting

DOEpatents

Powell, James R.; Reich, Morris

2001-09-04

A method of filling a canister with vitrified waste starting with a waste, such as high-level radioactive waste, that is cooler than its melting point. Waste is added incrementally to a canister forming a column of waste capable of being separated into an upper zone and a lower zone. The minimum height of the column is defined such that the waste in the lower zone can be dried and melted while maintaining the waste in the upper zone below its melting point. The maximum height of the column is such that the upper zone remains porous enough to permit evolved gases from the lower zone to flow through the upper zone and out of the canister. Heat is applied to the waste in the lower zone to first dry then to raise and maintain its temperature to a target temperature above the melting point of the waste. Then the heat is applied to a new lower zone above the melted waste and the process of adding, drying and melting the waste continues upward in the canister until the entire canister is filled and the entire contents are melted and maintained at the target temperature for the desired period. Cooling of the melted waste takes place incrementally from the bottom of the canister to the top, or across the entire canister surface area, forming a vitrified product.

System and method for producing metallic iron

DOEpatents

Bleifuss, Rodney L; Englund, David J; Iwasaki, Iwao; Fosnacht, Donald R; Brandon, Mark M; True, Bradford G

2013-09-17

A hearth furnace for producing metallic iron material has a furnace housing having a drying/preheat zone, a conversion zone, a fusion zone, and optionally a cooling zone, the conversion zone is between the drying/preheat zone and the fusion zone. A moving hearth is positioned within the furnace housing. A hood or separation barrier within at least a portion of the conversion zone, fusion zone or both separates the fusion zone into an upper region and a lower region with the lower region adjacent the hearth and the upper region adjacent the lower region and spaced from the hearth. An injector introduces a gaseous reductant into the lower region adjacent the hearth. A combustion region may be formed above the hood or separation barrier.

Oyster-bioimmured ammonites from the Upper Albian of Annopol, Poland: stratigraphic and palaeobiogeographic implications

NASA Astrophysics Data System (ADS)

Machalski, Marcin; Kennedy, William J.

2013-12-01

Machalski, M. and Kennedy, W.J. 2013. Oyster-bioimmured ammonites from the Upper Albian of Annopol, Poland: stratigraphic and palaeobiogeographic implications. Acta Geologica Polonica, 63 (4), 545-554. Warszawa. Ammonites Mortoniceras (Subschloenbachia) sp. are preserved as attachment scars on the oyster shells from the topmost portion of the Albian succession at Annopol, Poland. These oyster-bioimmured ammonites show a closest affinity to the representatives of Mortoniceras (Subschloenbachia) characteristic of the upper Upper Albian Mortoniceras perinflatum Zone. No ammonites indicative of the uppermost Albian-lowermost Cenomanian Praeschloenbachia briacensis Zone are recorded. Thus, the hiatus at the Albian-Cenomanian boundary at Annopol embraces the latter zone. The presence (and dominance) of Mortoniceras in the upper Upper Albian ammonite assemblage of Annopol suggests that the representatives of this Tethyan genus could migrate into the epicratonic areas of Poland directly from the Tethyan Realm, via the Lwow (Lviv) region.

47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

Code of Federal Regulations, 2011 CFR

2011-10-01

... safety coordinator. (1) The description must include, at a minimum; (i) The frequency or frequencies on... 47 Telecommunication 2 2011-10-01 2011-10-01 false Upper 700 MHz commercial and public safety... Rules for WCS § 27.303 Upper 700 MHz commercial and public safety coordination zone. (a) General. CMRS...

Quartz crystal growth

DOEpatents

Baughman, Richard J.

1992-01-01

A process for growing single crystals from an amorphous substance that can undergo phase transformation to the crystalline state in an appropriate solvent. The process is carried out in an autoclave having a lower dissolution zone and an upper crystallization zone between which a temperature differential (.DELTA.T) is maintained at all times. The apparatus loaded with the substance, solvent, and seed crystals is heated slowly maintaining a very low .DELTA.T between the warmer lower zone and cooler upper zone until the amorphous substance is transformed to the crystalline state in the lower zone. The heating rate is then increased to maintain a large .DELTA.T sufficient to increase material transport between the zones and rapid crystallization. .alpha.-Quartz single crystal can thus be made from fused quartz in caustic solvent by heating to 350.degree. C. stepwise with a .DELTA.T of 0.25.degree.-3.degree. C., increasing the .DELTA.T to about 50.degree. C. after the fused quartz has crystallized, and maintaining these conditions until crystal growth in the upper zone is completed.

Finite-frequency wave propagation through outer rise fault zones and seismic measurements of upper mantle hydration

USGS Publications Warehouse

Miller, Nathaniel; Lizarralde, Daniel

2016-01-01

Effects of serpentine-filled fault zones on seismic wave propagation in the upper mantle at the outer rise of subduction zones are evaluated using acoustic wave propagation models. Modeled wave speeds depend on azimuth, with slowest speeds in the fault-normal direction. Propagation is fastest along faults, but, for fault widths on the order of the seismic wavelength, apparent wave speeds in this direction depend on frequency. For the 5–12 Hz Pn arrivals used in tomographic studies, joint-parallel wavefronts are slowed by joints. This delay can account for the slowing seen in tomographic images of the outer rise upper mantle. At the Middle America Trench, confining serpentine to fault zones, as opposed to a uniform distribution, reduces estimates of bulk upper mantle hydration from ~3.5 wt % to as low as 0.33 wt % H2O.

Perfusion scintigraphy and patient selection for lung volume reduction surgery.

PubMed

Chandra, Divay; Lipson, David A; Hoffman, Eric A; Hansen-Flaschen, John; Sciurba, Frank C; Decamp, Malcolm M; Reilly, John J; Washko, George R

2010-10-01

It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). To study the role of perfusion scintigraphy in patient selection for LVRS. We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non-high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non-upper lobe-predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Among 284 of 1,045 patients with upper lobe-predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe-predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non-upper lobe-predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe-predominant emphysema when there is low rather than high perfusion to the upper lung.

Evidence for long-lived subduction of an ancient tectonic plate beneath the southern Indian Ocean: Ancient Slab Beneath the Indian Ocean

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simmons, N. A.; Myers, S. C.; Johannesson, G.

In this study, ancient subducted tectonic plates have been observed in past seismic images of the mantle beneath North America and Eurasia, and it is likely that other ancient slab structures have remained largely hidden, particularly in the seismic-data-limited regions beneath the vast oceans in the Southern Hemisphere. Here we present a new global tomographic image, which shows a slab-like structure beneath the southern Indian Ocean with coherency from the upper mantle to the core-mantle boundary region—a feature that has never been identified. We postulate that the structure is an ancient tectonic plate that sank into the mantle along anmore » extensive intraoceanic subduction zone that migrated southwestward across the ancient Tethys Ocean in the Mesozoic Era. Slab material still trapped in the transition zone is positioned near the edge of East Gondwana at 140 Ma suggesting that subduction terminated near the margin of the ancient continent prior to breakup and subsequent dispersal of its subcontinents.« less

Evidence for long-lived subduction of an ancient tectonic plate beneath the southern Indian Ocean: Ancient Slab Beneath the Indian Ocean

DOE PAGES

Simmons, N. A.; Myers, S. C.; Johannesson, G.; ...

2015-11-14

In this study, ancient subducted tectonic plates have been observed in past seismic images of the mantle beneath North America and Eurasia, and it is likely that other ancient slab structures have remained largely hidden, particularly in the seismic-data-limited regions beneath the vast oceans in the Southern Hemisphere. Here we present a new global tomographic image, which shows a slab-like structure beneath the southern Indian Ocean with coherency from the upper mantle to the core-mantle boundary region—a feature that has never been identified. We postulate that the structure is an ancient tectonic plate that sank into the mantle along anmore » extensive intraoceanic subduction zone that migrated southwestward across the ancient Tethys Ocean in the Mesozoic Era. Slab material still trapped in the transition zone is positioned near the edge of East Gondwana at 140 Ma suggesting that subduction terminated near the margin of the ancient continent prior to breakup and subsequent dispersal of its subcontinents.« less

A low-angle detachment fault revealed: Three-dimensional images of the S-reflector fault zone along the Galicia passive margin

NASA Astrophysics Data System (ADS)

Schuba, C. Nur; Gray, Gary G.; Morgan, Julia K.; Sawyer, Dale S.; Shillington, Donna J.; Reston, Tim J.; Bull, Jonathan M.; Jordan, Brian E.

2018-06-01

A new 3-D seismic reflection volume over the Galicia margin continent-ocean transition zone provides an unprecedented view of the prominent S-reflector detachment fault that underlies the outer part of the margin. This volume images the fault's structure from breakaway to termination. The filtered time-structure map of the S-reflector shows coherent corrugations parallel to the expected paleo-extension directions with an average azimuth of 107°. These corrugations maintain their orientations, wavelengths and amplitudes where overlying faults sole into the S-reflector, suggesting that the parts of the detachment fault containing multiple crustal blocks may have slipped as discrete units during its late stages. Another interface above the S-reflector, here named S‧, is identified and interpreted as the upper boundary of the fault zone associated with the detachment fault. This layer, named the S-interval, thickens by tens of meters from SE to NW in the direction of transport. Localized thick accumulations also occur near overlying fault intersections, suggesting either non-uniform fault rock production, or redistribution of fault rock during slip. These observations have important implications for understanding how detachment faults form and evolve over time. 3-D seismic reflection imaging has enabled unique insights into fault slip history, fault rock production and redistribution.

77 FR 53769 - Safety Zone; Liberty to Freedom Swims, Liberty Island, Upper Bay and Hudson River, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-04

... 1625-AA00 Safety Zone; Liberty to Freedom Swims, Liberty Island, Upper Bay and Hudson River, NY AGENCY... September 5, 2012 and September 15, 2012 Liberty to Freedom swim events. This temporary safety zone is necessary to protect the maritime public and event participants from the hazards associated with swim events...

Fault pattern at the northern end of the Death Valley - Furnace Creek fault zone, California and Nevada

NASA Technical Reports Server (NTRS)

Liggett, M. A. (Principal Investigator); Childs, J. F.

1974-01-01

The author has identified the following significant results. The pattern of faulting associated with the termination of the Death Valley-Furnace Creek Fault Zone in northern Fish Lake Valley, Nevada was studied in ERTS-1 MSS color composite imagery and color IR U-2 photography. Imagery analysis was supported by field reconnaissance and low altitude aerial photography. The northwest-trending right-lateral Death Valley-Furnace Creek Fault Zone changes northward to a complex pattern of discontinuous dip slip and strike slip faults. This fault pattern terminates to the north against an east-northeast trending zone herein called the Montgomery Fault Zone. No evidence for continuation of the Death Valley-Furnace Creek Fault Zone is recognized north of the Montgomery Fault Zone. Penecontemporaneous displacement in the Death Valley-Furnace Creek Fault Zone, the complex transitional zone, and the Montgomery Fault Zone suggests that the systems are genetically related. Mercury mineralization appears to have been localized along faults recognizable in ERTS-1 imagery within the transitional zone and the Montgomery Fault Zone.

An object-oriented model of the cardiopulmonary system with emphasis on the gravity effect.

PubMed

Chuong Ngo; Herranz, Silvia Briones; Misgeld, Berno; Vollmer, Thomas; Leonhardt, Steffen

2016-08-01

We introduce a novel comprehensive model of the cardiopulmonary system with emphasis on perfusion and ventilation distribution along the vertical thorax axis under the gravity effect. By using an object-oriented environment, the complex physiological system can be represented by a network of electrical, lumped-element compartments. The lungs are divided into three zones: upper, middle, and lower zone. Blood flow increases with the distance from the apex to the base of the lungs. The upper zone is characterized by a complete collapse of the pulmonary capillary vasculature; thus, there is no flow in this zone. The second zone has a "waterfall effect" where the blood flow is determined by the difference between the pulmonary-arterial and alveolar pressures. At resting position, the upper lobes of the lungs are more expanded than the middle and lower lobes. However, during spontaneous breathing, ventilation is nonuniform with more air entering the lower lobes than the middle and upper lobes. A simulative model of the complete system is developed which shows results in good agreement with the literature.

The Daptocephalus Assemblage Zone (Lopingian), South Africa: A proposed biostratigraphy based on a new compilation of stratigraphic ranges

NASA Astrophysics Data System (ADS)

Viglietti, Pia A.; Smith, Roger M. H.; Angielczyk, Kenneth D.; Kammerer, Christian F.; Fröbisch, Jörg; Rubidge, Bruce S.

2016-01-01

The Dicynodon Assemblage Zone (DiAZ) of South Africa's Karoo Basin is one of the eight biostratigraphic zones of the Beaufort Group. It spans the uppermost Permian strata (Balfour, Teekloof, and Normandien formations) and traditionally has been considered to terminate with the disappearance of Dicynodon lacerticeps at the Permo-Triassic Boundary. We demonstrate that the three index fossils currently used to define the Dicynodon Assemblage Zone (Dicynodon lacerticeps, Theriognathus microps, and Procynosuchus delaharpeae) have first appearance datums (FADs) below its traditionally recognized lower boundary and have ranges mostly restricted to the lower portion of the biozone, well below the Permo-Triassic Boundary. We propose re-establishing Daptocephalus leoniceps as an index fossil for this stratigraphic interval, and reinstating the name Daptocephalus Assemblage Zone (DaAZ) for this unit. Furthermore, the FAD of Lystrosaurus maccaigi in the uppermost reaches of the biozone calls for the establishment of a two-fold subdivision of the current Dicynodon Assemblage Zone. The biostratigraphic utility of Da. leoniceps and other South African dicynodontoids outside of the Karoo Basin is limited due to basinal endemism at the species level and varying temporal ranges of dicynodontoids globally. Therefore, we recommend their use only for correlation within the Karoo Basin at this time. Revision of the stratigraphic ranges of all late Permian tetrapods does not reveal a significant change in faunal diversity between the lower and upper DaAZ. However, the last appearance datums of the abundant taxa Di. lacerticeps, T. microps, P. delaharpeae, and Diictodon feliceps occur below the three extinction phases associated with the end-Permian mass extinction event. Due to northward attenuation of the strata, however, the stratigraphic position of the extinction phases may need to be reconsidered.

Bacterioplankton Populations within the Oxygen Minimum Zone of the Sargasso Sea

NASA Astrophysics Data System (ADS)

Schuler, G.; Parsons, R. J.; Johnson, R. J.

2016-02-01

Oxygen minimum zones are present throughout the world's oceans, and occur at depths between 200 to 1000m. Heterotrophic bacteria reduce the dissolved oxygen within this layer through respiration, while metabolizing falling particles. This report studied the bacterioplankton in the oxygen minimum zone at the BATS (Bermuda Atlantic Times-series Study) site from July 2014 until November 2014. Total bacterioplankton populations were enumerated through direct counts. In the transitional zone (400m-800m) of the oxygen minimum zone, a secondary bacterioplankton peak formed. This study used FISH (Fluorescent in situ hybridization) and CARD-FISH (Catalyzed Reporter Deposition-Fluorescent in situ hybridization) to enumerate specific bacterial and archaeal taxa. Crenarchaeota (including Thaumarchaeota) increased in abundance within the upper oxycline. Thaumarchaeota have the ammonia monooxygenase gene that oxidizes ammonium into nitrite in low oxygen conditions. Amplification of the amoA gene confirmed that ammonia oxidizing archaea (AOA) were present within the OMZ. Using Terminal Restriction Fragment Length Polymorphism (T-RFLP), the bacterial community structure showed high similarity based depth zones (0-80m, 160-600m, and 800-4500m). Niskin experiments determined that water collected at 800m had an exponential increase in bacterioplankton over time. While experimental design did not allow for oxygen levels to be maintained, the bacterioplankton community was predominantly bacteria with eubacteria positive cells making up 89.3% of the of the total bacterioplankton community by day 34. Improvements to the experimental design are required to determine which specific bacterial taxa caused this increase at 800m. This study suggests that there are factors other than oxygen influencing bacterioplankton populations at the BATS site, and more analysis is needed once the BATS data is available to determine the key drivers of bacterioplankton dynamics within the BATS OMZ.

System and method for producing metallic iron

DOEpatents

Bleifuss, Rodney L [Grand Rapids, MN; Englund, David J [Bovey, MN; Iwasaki, Iwao [Grand Rapids, MN; Fosnacht, Donald R [Hermantown, MN; Brandon, Mark M [Charlotte, NC; True, Bradford G [Charlotte, NC

2012-01-17

A hearth furnace 10 for producing metallic iron material has a furnace housing 11 having a drying/preheat zone 12, a conversion zone 13, a fusion zone 14, and optionally a cooling zone 15, the conversion zone 13 is between the drying/preheat zone 12 and the fusion zone 14. A moving hearth 20 is positioned within the furnace housing 11. A hood or separation barrier 30 within at least a portion of the conversion zone 13, fusion zone 14 or both separates the fusion zone 14 into an upper region and a lower region with the lower region adjacent the hearth 20 and the upper region adjacent the lower region and spaced from the hearth 20. An injector introduces a gaseous reductant into the lower region adjacent the hearth 20. A combustion region may be formed above the hood or separation barrier.

Superstructure high efficiency photovoltaics

NASA Technical Reports Server (NTRS)

Wagner, M.; So, L. C.; Leburton, J. P.

1987-01-01

A novel class of photovoltaic cascade structures is introduced which features multijunction upper subcells. These superstructure high efficiency photovoltaics (SHEP's) exhibit enhanced upper subcell spectral response because of the additional junctions which serve to reduce bulk recombination losses by decreasing the mean collection distance for photogenerated minority carriers. Two possible electrical configurations were studied and compared: a three-terminal scheme that allows both subcells to be operated at their individual maximum power points and a two-terminal configuration with an intercell ohmic contact for series interconnection. The three-terminal devices were found to be superior both in terms of beginning-of-life expectancy and radiation tolerance. Realistic simulations of three-terminal AlGaAs/GaAs SHEP's show that one sun AMO efficiencies in excess of 26 percent are possible.

Hydrogeologic framework and geochemistry of the intermediate aquifer system in parts of Charlotte, De Soto, and Sarasota counties, Florida

USGS Publications Warehouse

Torres, A.E.; Sacks, L.A.; Yobbi, D.K.; Knochenmus, L.A.; Katz, B.G.

2001-01-01

The hydrogeologic framework underlying the 600-square-mile study area in Charlotte, De Soto, and Sarasota Counties, Florida, consists of the surficial aquifer system, the intermediate aquifer system, and the Upper Floridan aquifer. The hydrogeologic framework and the geochemical processes controlling ground-water composition were evaluated for the study area. Particular emphasis was given to the analysis of hydrogeologic and geochemical data for the intermediate aquifer system. Flow regimes are not well understood in the intermediate aquifer system; therefore, hydrogeologic and geochemical information were used to evaluate connections between permeable zones within the intermediate aquifer system and between overlying and underlying aquifer systems. Knowledge of these connections will ultimately help to protect ground-water quality in the intermediate aquifer system. The hydrogeology was interpreted from lithologic and geophysical logs, water levels, hydraulic properties, and water quality from six separate well sites. Water-quality samples were collected from wells located along six ground-water flow paths and finished at different depth intervals. The selection of flow paths was based on current potentiometric-surface maps. Ground-water samples were analyzed for major ions; field parameters (temperature, pH, specific conductance, and alkalinity); stable isotopes (deuterium, oxygen-18, and carbon-13); and radioactive isotopes (tritium and carbon-14). The surficial aquifer system is the uppermost aquifer, is unconfined, relatively thin, and consists of unconsolidated sand, shell, and limestone. The intermediate aquifer system underlies the surficial aquifer system and is composed of clastic sediments interbedded with carbonate rocks. The intermediate aquifer system is divided into three permeable zones, the Tamiami/Peace River zone (PZ1), the Upper Arcadia zone (PZ2), and the Lower Arcadia zone (PZ3). The Tamiami/Peace River zone (PZ1) is the uppermost zone and is the thinnest and generally, the least productive zone in the intermediate aquifer system. The Upper Arcadia zone (PZ2) is the middle zone and productivity is generally higher than the overlying permeable zone. The Lower Arcadia zone (PZ3) is the lowermost permeable zone and is the most productive zone in the intermediate aquifer system. The intermediate aquifer system is underlain by the Upper Floridan aquifer, which consists of a thick, stratified sequence of limestone and dolomite. The Upper Floridan aquifer is the most productive aquifer in the study area; however, its use is generally restricted because of poor water quality. Interbedded clays and fine-grained clastics separate the aquifer systems and permeable zones. The hydraulic properties of the three aquifer systems are spatially variable. Estimated trans-missivity and horizontal hydraulic conductivity varies from 752 to 32,900 feet squared per day and from 33 to 1,490 feet per day, respectively, for the surficial aquifer system; from 47 to 5,420 feet squared per day and from 2 to 102 feet per day, respectively, for the Tamiami/Peace River zone (PZ1); from 258 to 24,633 feet squared per day and from 2 to 14 feet per day, respectively, for the Upper Arcadia zone (PZ2); from 766 to 44,900 feet squared per day and from 10 to 201 feet per day, respectively, for the Lower Arcadia zone (PZ3); and from 2,350 to 7,640 feet squared per day and from 10 to 41 feet per day, respectively, for the Upper Floridan aquifer. Confining units separating the aquifer systems have leakance coefficients estimated to range from 2.3 x 10-5 to 5.6 x 10-3 feet per day per foot. Strata composing the confining unit separating the Upper Floridan aquifer from the intermediate aquifer system are substantially more permeable than confining units separating the permeable zones in the intermediate aquifer system or separating the surficial aquifer and intermediate aquifer systems. In Charlotte, Sarasota, and western De Soto Counties, hydraulic

Modelling reaction front formation and oscillatory behaviour in a contaminant plume

NASA Astrophysics Data System (ADS)

Cribbin, Laura; Fowler, Andrew; Mitchell, Sarah; Winstanley, Henry

2013-04-01

Groundwater contamination is a concern in all industrialised countries that suffer countless spills and leaks of various contaminants. Often, the contaminated groundwater forms a plume that, under the influences of regional groundwater flow, could eventually migrate to streams or wells. This can have catastrophic consequences for human health and local wildlife. The process known as bioremediation removes pollutants in the contaminated groundwater through bacterial reactions. Microorganisms can transform the contaminant into less harmful metabolic products. It is important to be able to predict whether such bioremediation will be sufficient for the safe clean-up of a plume before it reaches wells or lakes. Borehole data from a contaminant plume which resulted from spillage at a coal carbonisation plant in Mansfield, England is the motivation behind modelling the properties of a contaminant plume. In the upper part of the plume, oxygen is consumed and a nitrate spike forms. Deep inside the plume, nitrate is depleted and oscillations of organic carbon and ammonium concentration profiles are observed. While there are various numerical models that predict the evolution of a contaminant plume, we aim to create a simplified model that captures the fundamental characteristics of the plume while being comparable in accuracy to the detailed numerical models that currently exist. To model the transport of a contaminant, we consider the redox reactions that occur in groundwater systems. These reactions deplete the contaminant while creating zones of dominant terminal electron accepting processes throughout the plume. The contaminant is depleted by a series of terminal electron acceptors, the order of which is typically oxygen, nitrate, manganese, iron, sulphate and carbon dioxide. We describe a reaction front, characteristic of a redox zone, by means of rapid reaction and slow diffusion. This aids in describing the depletion of oxygen in the upper part of the plume. To describe the oscillatory behaviour of the reactant concentrations deeper in the plume, we employ the dynamics of competing bacterial populations. We show that the oscillatory behaviour, characteristic of competing populations, can describe the oscillations observed among the reactants.

Cyclic flow underground coal gasification process

DOEpatents

Bissett, Larry A.

1978-01-01

The present invention is directed to a method of in situ coal gasification for providing the product gas with an enriched concentration of carbon monoxide. The method is practiced by establishing a pair of combustion zones in spaced-apart boreholes within a subterranean coal bed and then cyclically terminating the combustion in the first of the two zones to establish a forward burn in the coal bed so that while an exothermic reaction is occurring in the second combustion zone to provide CO.sub.2 -laden product gas, an endothermic CO-forming reaction is occurring in the first combustion zone between the CO.sub.2 -laden gas percolating thereinto and the hot carbon in the wall defining the first combustion zone to increase the concentration of CO in the product gas. When the endothermic reaction slows to a selected activity the roles of the combustion zones are reversed by re-establishing an exothermic combustion reaction in the first zone and terminating the combustion in the second zone.

75 FR 42690 - Reorganization of Foreign-Trade Zone 121 Under Alternative Site Framework Capital District, New York

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

..., FTZ 121's existing Sites 1, 2 and 3, and new Sites 5 and 6 would be categorized as magnet sites... general-purpose zone project, to a five-year ASF sunset provision for magnet sites that would terminate... ASF sunset provision that would terminate authority for magnet Site 5 if not activated by June 30...

Summary of hydrologic testing of the Floridan aquifer system at Fort Stewart, Georgia

USGS Publications Warehouse

Gonthier, Gerard

2011-01-01

Flowmeter surveys at the study site indicate several permeable zones within the Floridan aquifer system. The Upper Floridan aquifer is composed of two water-bearing zones-the upper zone and the lower zone. The upper zone extends from 520 to 650 feet below land surface, contributes 96 percent of the total flow, and is more permeable than the lower zone, which extends from 650 to 705 feet below land surface and contributes the remaining 4 percent of the flow. The Lower Floridan aquifer consists of three zones at depths of 912-947, 1,090-1,139, and 1,211-1,250 feet below land surface that are inter-layered with three less-permeable zones. The Lower Floridan confining unit includes a permeable zone that extends from 793 to 822 feet below land surface. Horizontal hydraulic conductivity values of the Lower Floridan confining unit derived from slug tests within four packer-isolated intervals were from 2 to 20 feet per day, with a high value of 70 feet per day obtained for one of the intervals. Aquifer testing, using analytical techniques and model simulation, indicated the Upper Floridan aquifer had a transmissivity of about 100,000 feet squared per day, and the Lower Floridan aquifer had a transmissivity of 7,000 feet squared per day. Flowmeter surveys, slug tests within packer-isolated intervals, and parameter-estimation results indicate that the hydraulic properties of the Lower Floridan confining unit are similar to those of the Lower Floridan aquifer. Water-level data, for each aquifer test, were filtered for external influences such as barometric pressure, earth-tide effects, and long-term trends to enable detection of small water-level responses to aquifer-test pumping of less than 1 foot. During a 72-hour aquifer test of the Lower Floridan aquifer, a drawdown response of 0.3 to 0.4 foot was observed in two Upper Floridan aquifer wells, one of which was more than 1 mile away from the pumped well.

75 FR 53963 - Iron Mask Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

...-long upper dam made of either zoned earth and rockfill or concrete-face earth and rockfill; (2) a 50-foot-high, 950-foot-long earth-filled upper saddle dike A; (3) a 20-foot-high, 400-foot-long earth-filled upper saddle dike B; (4) a 40-foot-high, 6,559-foot-long lower embankment made of zoned earth or...

Upper Cretaceous planktonic stratigraphy of the Göynük composite section, western Tethys (Bolu province, Turkey)

NASA Astrophysics Data System (ADS)

Wolfgring, Erik; Liu, Shasha; Wagreich, Michael; Böhm, Katharina; Omer Yilmaz, Ismail

2017-04-01

Upper Cretaceous strata exposed at Göynük (Mudurnu-Göynük basin, Bolu Province, Northwestern Anatolia, Turkey) provide a composite geological record from the Upper Santonian to the Maastrichtian. Deposits in this area originate from the Sakarya continent, therefore, a western Tethyan palaeogeographic setting with a palaeolatitude of a bit less than 30 degrees north can be reconstructed. Grey shales and clayey marls are exposed at Göynük and do frequently show volcanic intercalations in the oldest parts of the section, while the uppermost layers depict a more complete deeper-marine record. The pelagic palaeoenvironment, microfossil indicators point towards a distal slope setting, at the Göynük section comprises rich low-latitude planktonic foraminiferal and calcareous nannoplankton assemblages. Benthic foraminifera are scarce, however, some biostratigraphically indicative taxa were recovered. The three sections sampled for this study reveal a composite record from the Campanian Contusotruncana plummerae planktonic foraminifera Zone to the Maastrichtian Racemiguembelina fruticosa planktonic foraminifera Zone. The oldest sub section („GK-section") yields the „mid" Campanian Contusotruncana plummerae or Globotruncana ventricosa Zones and is followed by the „GC-section". The oldest strata in latter record the C. plummerae Zone, the Radotruncana calcarata Zone, Globotruncanita havanensis as well as the Globotruncana aegyptiaca Zone and are overlain by the youngest section examined in this study ("GS -section"). In the latter, we recognize the G. aegyptiaca Zone in the lowermost part, the upper Campanian/lower Maastrichtian Gansserina gansseri Zone, and the Maastrichtian Racemiguembelina fruticosa Zone. Nannofossil standard zones UC15b to UC18 are recorded within the composite section. The planktonic foraminiferal assemblages assessed in the Göynük area feature a well preserved, diverse plankton record that can be correlated to other western Tethyan sections from the Upper Cretaceous. Especially the Austrian Alpine sections (i.e. Northern Calcareous Alps and Ultrahelvetics) show similar environmental and palaeolatitudinal settings and feature a well established biostratigraphical and cyclostratigraphic record. Comparing the multi-proxy record assessed in these sections to the biostratigraphic data from the Göynük region provides useful insights into planktonic foraminiferal palaeoecology and the multistratigraphic high-resolution correlation in the Upper Cretaceous Tethyan realm.

Paleontology and physical stratigraphy of the USGS-Pregnall No. 1 core (DOR-208), Dorchester County, South Carolina

USGS Publications Warehouse

Edwards, L.E.; Bybell, L.M.; Gohn, G.S.; Frederiksen, N.O.

1997-01-01

Pregnall No. 1, a 346-ft-deep corehole in northern Dorchester County, South Carolina, recovered sediments of late Paleocene, middle and late Eocene, and late Oligocene age. The core bottomed in the Chicora Member of the Williamsburg Formation (Black Mingo Group) of late Paleocene age (calcareous nannofossil Zones NP 7/8 (?) and NP 9). The Chicora (346 to 258 ft depth) consists of two contrasting lithologic units, a lower siliciclastic section of terrigenous sand, silt, and clay, and an upper carbonate section of moldic pelecypod limestone. The Chicora is overlain unconformably by the middle Eocene Moultrie Member of the Santee Limestone (Orangeburg Group). The Moultrie (258.0 to 189.4 ft) consists primarily of bryozoan-pelecypod-peloid packstones and grainstones, which are assigned to calcareous nannofossil Zone NP 16. Unconformably above the Moultrie are the locally shelly, microfossiliferous limestones of the Cross Member of the Santee Limestone (Orangeburg Group), which are assigned to middle Eocene Zone NP 17 and upper Eocene Zone NP 18. The Cross Member (189.4 to 90.9 ft) is unconformably overlain by a very thin, basal section of the upper Eocene Harleyville Formation (Cooper Group). The thin Harleyville section consists of fossiliferous limestone, primarily pelecypod-foraminifer-peloid packstones (90.9 to 85.8 ft), and is assigned to Zone NP 18, although samples from thicker Harleyville sections in the region typically are assigned to upper Eocene Zone NP 19/20. The Harleyville is overlain unconformably by the upper Oligocene Ashley Formation (Cooper Group). The Ashley Formation (85.8 to 30.0 ft) consists of a relatively homogeneous section of calcareous, microfossiliferous, silty and sandy clays assigned to Zones NP 24 and NP 25 (?). Neogene and (or) Quaternary deposits present in the upper 30 ft of the Pregnall section are assigned provisionally to an unnamed unit (30 to 22 ft) and to the Waccamaw Formation(?)(22 to 0 ft).

Earth Observations taken by the Expedition 27 Crew

NASA Image and Video Library

2011-04-12

ISS027-E-012224 (12 April 2011) --- Sunset over western South America is featured in this image photographed by an Expedition 27 crew member on the International Space Station. Crew members onboard the space station see, on average, sixteen sunrises and sunsets during a 24-hour orbital period. Each changeover between day and night on the ground is marked by the terminator, or line separating the sunlit side of Earth from the side in darkness. While the terminator is conceptualized as a hard boundary?and is frequently presented as such in graphics and visualizations?in reality the boundary between light and dark is diffuse due to scattering of light by Earth?s atmosphere. This zone of diffuse lighting is experienced as dusk or twilight on the ground ? while the sun is no longer visible, some illumination is still present due to light scattering over the local horizon. The terminator is visible in this photograph trending across the image from lower left to upper right. This panoramic view across central South America, looking towards the northeast, was acquired at approximately 7:37 p.m. local time. Layers of Earth?s atmosphere, colored bright white to deep blue, are visible extending across the horizon (or limb). The highest cloud tops have a reddish glow from the direct light of the setting sun while lower clouds are in twilight. The Salar de Coipasa, a large salt lake in Bolivia, is dimly visible on the night side of the terminator. The salar provides a geographic reference point that allows the location and viewing orientation of the image to be determined.

Chloride Concentration in Water from the Upper Permeable Zone of the Tertiary Limestone Aquifer System, Southeastern United States

USGS Publications Warehouse

Sprinkle, Craig L.

1982-01-01

INTRODUCTION The tertiary limestone aquifer system of the southeastern United States is a sequence of carbonate rocks referred to as the Floridan aquifer in Florida and the principal artesian aquifer in Georgia, Alabama, and South Carolina. More than 3 billion gallons of water are pumped daily from the limestone aquifer; and the system is the principal source of municipal, industrial, and agricultural water supply in south Georgia and most of Florida. The aquifer system includes units of Paleocene to early Miocene age that combine to form a continuous carbonate sequence that is hydraulically connected in varying degrees. In a small area near Brunswick, Ga., a thin sequence of rocks of Late Cretaceous age is part of the system. In and directly downdip from much of the outcrop area, the system consists of one continuous permeable unit. Further downdip the aquifer system generally consists of two major permeable zones separated by a less-permeable unit of highly variable hydraulic properties (very leaky to virtually nonleaky). Conditions for the system vary from unconfined to confined depending upon whether the argillaceous Miocene and younger rocks that form the upper confining unit have been removed by erosion. This report is one of a series of preliminary products depicting the hydrogeologic framework, water chemistry, and hydrology of the aquifer system. The map shows the distribution of chloride ions in water from the upper permeable zone of the limestone aquifer system. The upper permeable zone consists of several formations, primarily the Tampa, Suwannee, Ocala, and Avon Park Limestones (Miller 1981a, b). Chloride concentrations of water within the upper permeable zone vary from nearly zero in recharge areas to many thousands of milligrams per liter (mg/L) in coastal discharge areas. Where the aquifer system discharges into the sea, the upper permeable zone contains increasing amounts of seawater. In these areas, wells that fully penetrate the upper permeable zone will yield water with chloride concentrations that approach that of seawater, about 19500 mg/L.

Processing α-mercuric iodide by zone refining

NASA Astrophysics Data System (ADS)

Burger, A.; Morgan, S. H.; Henderson, D. O.; Biao, Y.; Zhang, K.; Silberman, E.; Nason, D.; van den Berg, L.; Ortale-Baccash, C.; Cross, E.

1993-03-01

An investigation is being conducted on zone refining α-mercuric iodide. Analytical studies using differential scanning calorimetry and anion chromatography indicate that impurities are accumulated mainly at the end where zone travel terminates. Early results indicate that single crystals can be readily grown from zone-refined material.

Asymptotic study of pulsating evolution of overdriven and CJ detonation with a chain-branching kinetics model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Short, Mark; Chliquete, Carlos

2011-01-20

The pulsating dynamics of gaseous detonations with a model two-step chain-branching kinetic mechanism are studied both numerically and asymptotically. The model studied here was also used in [4], [3] and [2] and mimics the attributes of some chain-branching reaction mechanisms. Specifically, the model comprises a chain-initiationlbranching zone with an Arrhenius temperature-sensitive rate behind the detonation shock where fuel is converted into chain-radical with no heat release. This is followed by a chain-termination zone having a temperature insensitive rate where the exothermic heat of reaction is released. The lengths of these two zones depend on the relative rates of each stage.more » It was determined in [4] and [3] via asymptotic and numerical analysis that the ratio of the length of the chain-branching zone to that of the chain-initation zone relative to the size of the von Neumann state scaled activation energy in the chain initiation/branching zone has a primary influence of the stability of one-dimensional pulsating instability behavior for this model. In [2], the notion of a specific stability parameter related to this ratio was proposed that determines the boundary between stable and unstable waves. In [4], a slow-time varying asymptotic study was conducted of pulsating instability of Chapman-Jouguet (CJ) detonations with the above two-step rate model, assuming a large activation energy for the chain-initiation zone and a chain-termination zone longer than the chain-initiation zone. Deviations D{sub n}{sup (1)} ({tau}) of the detonation velocity from Chapman-Jouguet were of the order of the non-dimensional activation energy. Solutions were sought for a pulsation timescale of the order of the non-dimensional activation energy times the particle transit time through the induction zone. On this time-scale, the evolution of the chain-initation zone is quasi-steady. In [4], a time-dependent non-linear evolution equation for D{sub n}{sup (1)} ({tau}) was then constructed via a perturbation procedure for cases where the ratio of the length of the chain-termination zone to chain-initiation zone was less than the non-dimensional activation energy. To leading order, the steady CJ detonation was found to be unstable; higher-order corrections lead to the construction of a stability limit between stable and unsteady pulsating solutions. One conclusion from this study is that for a stability limit to occur at leading order, the period of pulsation of the detonation must occur on the time scale of particle passage through the longer chain-termination zone, while the length of the chain-termination zone must be of order of the non-dimensional activation energy longer than the chain-initiation zone. The relevance of these suggested scalings was verified via numerical solutions of the full Euler system in [3], and formed the basis of the stability parameter criteria suggested in [2]. In the following, we formulate an asymptotic study based on these new suggested scales, studying the implications for describing pulsating behavior in gaseous chain-branching detonations. Specifically, we find that the chain-induction zone structure is the same as that studied in [4]. However, the study of unsteady evolution in the chain-termination region is now governed by a set of asymptotically derived nonlinear POEs. Equations for the linear stablity behavior of this set of POE's is obtained, while the nonlinear POEs are solved numerically using a shock-attached, shock-fitting method developed by Henrick et aJ. [1]. The results thus far show that the stability threshold calculated using the new ratio of the chain-termination zone length to that of the chain-initiation zone yields a marked improvement over [2]. Additionally, solutions will be compared with predictions obtained from the solution of the full Euler system. Finally, the evolution equation previously derived in [4] has been generalized to consider both arbitrary reaction orders and any degree of overdrive.« less

Silurian and Devonian in Vietnam—Stratigraphy and facies

NASA Astrophysics Data System (ADS)

Thanh, Tống Duy; Phương, Tạ Hoàng; Janvier, Philippe; Hùng, Nguyễn Hữu; Cúc, Nguyễn Thị Thu; Dương, Nguyễn Thùy

2013-09-01

Silurian and Devonian deposits in Viet Nam are present in several zones and regions, including Quang Ninh, East Bac Bo, and West Bac Bo Zones of the Bac Bo Region, the Dien Bien-Nghe An and Binh Tri Thien Zones of the Viet-Lao Region, and the South Trung Bo, and Western Nam Bo Zones of the South Viet Nam Region (Fig. 1). The main lithological features and faunal composition of the Silurian and Devonian Units in all these zones are briefly described. The Silurian consists of deep-water deposits of the upper parts of the Co To and Tan Mai Formations in the Quang Ninh Zone, the upper parts of the Phu Ngu Formation in the East Bac Bo Zone and the upper parts of the Long Dai and Song Ca Formations in the Viet-Lao Region. Shallow water facies Silurian units containing benthic faunas are more widely distributed, including the upper part of the Sinh Vinh and Bo Hieng Formations in the West Bac Bo Zone, the Kien An Formation in the Quang Ninh Zone, and, in the Viet-Lao Region, the Dai Giang Formation and the upper part of the Tay Trang Formation. No Lower and Middle Devonian deposits indicate deep water facies, but they are characterized by different shallow water facies. Continental to near shore, deltaic facies characterize the Lower Devonian Song Cau Group in the East Bac Bo Zone, the Van Canh Formation in the Quang Ninh Zone, and the A Choc Formation in the Binh Tri Thien Zone. Similar facies also occur in the Givetian Do Son Formation of the Quang Ninh Zone, and the Tan Lap Formation in the East Bac Bo Zone, and consist of coarse terrigenous deposits—cross-bedded conglomerates, sandstone, etc. Most Devonian units are characterized by shallow marine shelf facies. Carbonate and terrigenous-carbonate facies dominate, and terrigenous facies occur in the Lower and Middle Devonian sections in some areas only. The deep-water-like facies is characteriztic for some Upper Devonian formations in the Bac Bo (Bang Ca and Toc Tat Formations) and Viet-Lao Regions (Thien Nhan and Xom Nha Formations). These formations contain cherty shale or siliceous limestone, and fossils consist of conodonts, but there are also brachiopods and other benthos. They were possibly deposited in a deep water environment on the slope of the continental shelf. Most Devonian units distributed in the North and the Central Viet Nam consist of self shallow water sediments, and apparently they were deposited in a passive marginal marine environment. The coarse clastic continental or subcontinental deposits are distributed only in some areas of the East Bac Bo and of the Quang Ninh zones of the Bac Bo Region, and in the south of the Binh Tri Thien Zone. This situation suggests the influence of the Caledonian movement at the end of the Silurian period that called the Guangxi movement in South China.

Perfusion Scintigraphy and Patient Selection for Lung Volume Reduction Surgery

PubMed Central

Chandra, Divay; Lipson, David A.; Hoffman, Eric A.; Hansen-Flaschen, John; Sciurba, Frank C.; DeCamp, Malcolm M.; Reilly, John J.; Washko, George R.

2010-01-01

Rationale: It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). Objectives: To study the role of perfusion scintigraphy in patient selection for LVRS. Methods: We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non–high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non–upper lobe–predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Measurements and Main Results: Among 284 of 1,045 patients with upper lobe–predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe–predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non–upper lobe–predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Conclusions: Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe–predominant emphysema when there is low rather than high perfusion to the upper lung. PMID:20538961

Lithostratigraphy, biostratigraphy and chemostratigraphy of Upper Cretaceous sediments from southern Tanzania: Tanzania drilling project sites 21-26

NASA Astrophysics Data System (ADS)

Jiménez Berrocoso, Álvaro; MacLeod, Kenneth G.; Huber, Brian T.; Lees, Jacqueline A.; Wendler, Ines; Bown, Paul R.; Mweneinda, Amina K.; Isaza Londoño, Carolina; Singano, Joyce M.

2010-04-01

The 2007 drilling season by the Tanzania drilling project (TDP) reveals a much more expanded Upper Cretaceous sequence than was recognized previously in the Lindi region of southern Tanzania. This TDP expedition targeted recovery of excellently preserved microfossils (foraminifera and calcareous nannofossils) for Late Cretaceous paleoclimatic, paleoceanographic and biostratigraphic studies. A total of 501.17 m of core was drilled at six Upper Cretaceous sites (TDP Sites 21, 22, 23, 24, 24B and 26) and a thin Miocene-Pleistocene section (TDP Site 25). Microfossil preservation at all these sites is good to excellent, with foraminifera often showing glassy shells and consistently good preservation of small and delicate nannofossil taxa. In addition to adding to our knowledge of the subsurface geology, new surface exposures were mapped and the geological map of the region is revised herein. TDP Sites 24, 24B and 26 collectively span the upper Albian to lower-middle Turonian (planktonic foraminiferal Planomalina buxtorfi- Whiteinella archaeocretacea Zones and calcareous nannofossil zones UC0a-UC8a). The bottom of TDP Site 21 is barren, but the rest of the section represents the uppermost Cenomanian-Coniacian ( W. archaeocretacea- Dicarinella concavata Zones and nannofossil zones UC5c-UC10). Bulk organic δ 13C data suggest recovery of part of Ocean Anoxic Event 2 (OAE2) from these four sites. In the upper part of this interval, the lower Turonian nannofossil zones UC6a-7 are characterized by a low-diversity nannoflora that may be related to OAE2 surface-water conditions. TDP Site 22 presents a 122-m-thick, lower-middle Turonian ( W. archaeocretacea- Helvetoglobotruncana helvetica Zones) sequence that includes the nannofossil zones UC6a(-7?), but invariable isotopic curves. Further, a lower to upper Campanian ( Globotruncana ventricosa- Radotruncana calcarata Zones and nannofossil subzones UC15b TP-UC15d TP) succession was drilled at TDP Site 23. Lithologies of the new sites include thin units of gray, medium to coarse sandstones, separating much thicker intervals of dark claystones with organic-rich laminated parts, irregular silty to fine sandstone partings, and rare inoceramid and ammonite debris. These lithofacies are interpreted to have been deposited in outer shelf and upper slope settings and indicate relatively stable sedimentary conditions during most of the Late Cretaceous on the Tanzanian margin.

2. TERMINAL ROOM, SHOP LEVEL INTERIOR, SHOWING MEZZANINE LEVEL CABLE ...

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

2. TERMINAL ROOM, SHOP LEVEL INTERIOR, SHOWING MEZZANINE LEVEL CABLE RACK AT UPPER RIGHT. Looking north. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

Code of Federal Regulations, 2012 CFR

2012-10-01

... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

Code of Federal Regulations, 2014 CFR

2014-10-01

... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

Code of Federal Regulations, 2013 CFR

2013-10-01

... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

Hydrogeology and the distribution of salinity in the Floridan aquifer system, Palm Beach County, Florida

USGS Publications Warehouse

Reese, R.S.; Memberg, S.J.

2000-01-01

The virtually untapped Floridan aquifer system is considered to be a supplemental source of water for public use in the highly populated coastal area of Palm Beach County. A recent study was conducted to delineate the distribution of salinity in relation to the local hydrogeology and assess the potential processes that might control (or have affected) the distribution of salinity in the Floridan aquifer system. The Floridan aquifer system in the study area consists of the Upper Floridan aquifer, middle confining unit, and Lower Floridan aquifer and ranges in age from Paleocene to Oligocene. Included at its top is part of a lowermost Hawthorn Group unit referred to as the basal Hawthorn unit. The thickness of this basal unit is variable, ranging from about 30 to 355 feet; areas where this unit is thick were paleotopographic lows during deposition of the unit. The uppermost permeable zones in the Upper Floridan aquifer occur in close association with an unconformity at the base of the Hawthorn Group; however, the highest of these zones can be up in the basal unit. A dolomite unit of Eocene age generally marks the top of the Lower Floridan aquifer, but the top of this dolomite unit has a considerable altitude range: from about 1,200 to 2,300 feet below sea level. Additionally, where the dolomite unit is thick, its top is high and the middle confining unit of the Floridan aquifer system, as normally defined, probably is not present. An upper zone of brackish water and a lower zone of water with salinity similar to that of seawater (saline-water zone) are present in the Floridan aquifer system. The brackish-water and saline-water zones are separated by a transition zone (typically 100 to 200 feet thick) in which salinity rapidly increases with depth. The transition zone was defined by using a salinity of 10,000 mg/L (milligrams per liter) of dissolved-solids concentration (about 5,240 mg/L of chloride concentration) at its top and 35,000 mg/L of dissolved-solids concentration (about 18,900 mg/L of chloride concentration) at its base. The base of the brackish-water zone and the top of the saline-water zone were approximately determined mostly by means of resistivity geophysical logs. The base of the brackish-water zone in the study area ranges from about 1,600 feet below sea level near the coast to almost 2,200 feet below sea level in extreme southwestern Palm Beach County. In an area that is peripheral to Lake Okeechobee, the boundary unexpectedly rises to perhaps as shallow as 1,800 feet below sea level. In an upper interval of the brackish-water zone within the Upper Floridan aquifer, chloride concentration of water ranges from 490 to 8,000 mg/L. Chloride concentration correlates with the altitude of the basal contact of the Hawthorn Group, with concentration increasing as the altitude of this contact decreases. Several areas of anomalous salinity where chloride concentration in this upper interval is greater than 3,000 mg/L occur near the coast. In most of these areas, salinity was found to decrease with depth from the upper interval to a lower interval within the brackish-water zone: a reversal of the normal salinity trend within the zone. These areas are also characterized by an anomalously low altitude of the base of the brackish-water zone, and a much greater thickness of the transition zone than normal. These anomalies could be the result of seawater preferentially invading zones of higher permeability in the Upper Floridan aquifer during Pleistocene high stands of sea level and incomplete flushing of this high salinity water by the present-day flow system.

Seismic Tomography of the Arabian-Eurasian Collision Zone and Surrounding Areas

DTIC Science & Technology

2010-05-20

zone. The crustal models correlate well with geologic and tectonic features. The upper mantle tomograms show the images of the subducted Neotethys...We first obtain Pn and Sn velocities using local and regional arrival time data. Second, we obtain the 3-D crustal P and S velocity models...teleseismic tomography provides a high-resolution, 3-D P-wave velocity model for the crust, upper mantle, and the transition zone. The crustal models

A viscoplastic shear-zone model for episodic slow slip events in oceanic subduction zones

NASA Astrophysics Data System (ADS)

Yin, A.; Meng, L.

2016-12-01

Episodic slow slip events occur widely along oceanic subduction zones at the brittle-ductile transition depths ( 20-50 km). Although efforts have been devoted to unravel their mechanical origins, it remains unclear about the physical controls on the wide range of their recurrence intervals and slip durations. In this study we present a simple mechanical model that attempts to account for the observed temporal evolution of slow slip events. In our model we assume that slow slip events occur in a viscoplastic shear zone (i.e., Bingham material), which has an upper static and a lower dynamic plastic yield strength. We further assume that the hanging wall deformation is approximated as an elastic spring. We envision the shear zone to be initially locked during forward/landward motion but is subsequently unlocked when the elastic and gravity-induced stress exceeds the static yield strength of the shear zone. This leads to backward/trenchward motion damped by viscous shear-zone deformation. As the elastic spring progressively loosens, the hanging wall velocity evolves with time and the viscous shear stress eventually reaches the dynamic yield strength. This is followed by the termination of the trenchward motion when the elastic stress is balanced by the dynamic yield strength of the shear zone and the gravity. In order to account for the zig-saw slip-history pattern of typical repeated slow slip events, we assume that the shear zone progressively strengthens after each slow slip cycle, possibly caused by dilatancy as commonly assumed or by progressive fault healing through solution-transport mechanisms. We quantify our conceptual model by obtaining simple analytical solutions. Our model results suggest that the duration of the landward motion increases with the down-dip length and the static yield strength of the shear zone, but decreases with the ambient loading velocity and the elastic modulus of the hanging wall. The duration of the backward/trenchward motion depends on the thickness, viscosity, and dynamic yield strength of the shear zone. Our model predicts a linear increase in slip with time during the landward motion and an exponential decrease in slip magnitude during the trenchward motion.

Abrupt Upper-Plate Tilting Upon Slab-Transition-Zone Collision

NASA Astrophysics Data System (ADS)

Crameri, F.; Lithgow-Bertelloni, C. R.

2017-12-01

During its sinking, the remnant of a surface plate crosses and interacts with multiple boundaries in Earth's interior. The most-prominent dynamic interaction arises at the upper-mantle transition zone where the sinking plate is strongly affected by the higher-viscosity lower mantle. Within our numerical model, we unravel, for the first time, that this very collision of the sinking slab with the transition zone induces a sudden, dramatic downward tilt of the upper plate towards the subduction trench. The slab-transition zone collision sets parts of the higher-viscosity lower mantle in motion. Naturally, this then induces an overall larger return flow cell that, at its onset, tilts the upper plate abruptly by around 0.05 degrees and over around 10 Millions of years. Such a significant and abrupt variation in surface topography should be clearly visible in temporal geologic records of large-scale surface elevation and might explain continental-wide tilting as observed in Australia since the Eocene or North America during the Phanerozoic. Unravelling this crucial mantle-lithosphere interaction was possible thanks to state-of-the-art numerical modelling (powered by StagYY; Tackley 2008, PEPI) and post-processing (powered by StagLab; www.fabiocrameri.ch/software). The new model that is introduced here to study the dynamically self-consistent temporal evolution of subduction features accurate subduction-zone topography, robust single-sided plate sinking, stronger plates close to laboratory values, an upper-mantle phase transition and, crucially, simple continents at a free surface. A novel, fully-automated post-processing includes physical model diagnostics like slab geometry, mantle flow pattern, upper-plate tilt angle and trench location.

Method of operating a coal gasifier

DOEpatents

Blaskowski, Henry J.

1979-01-01

A method of operating an entrained flow coal gasifier which comprises the steps of firing coal at two levels in a combustion zone with near stoichiometric air, removing molten ash from the combustion zone, conveying combustion products upwardly from the combustion zone through a reduction zone, injecting additional coal into the combustion products in the reduction zone and gasifying at least a portion of the coal to form low BTU gas, conveying the gas to a point of use, including also reducing gasifier output by modifying the ratio of air to coal supplied to the upper level of the combustion zone so that the ratio becomes increasingly substoichiometric thereby extending the gasification of coal from the reduction zone into the upper level of the combustion zone, and maintaining the lower level of coal in the combustion zone at near stoichiometric conditions so as to provide sufficient heat to maintain effective slagging conditions.

Geology, hydrology, and water quality of the Tracy-Dos Palos area, San Joaquin Valley, California

USGS Publications Warehouse

Hotchkiss, W.R.; Balding, G.O.

1971-01-01

The Tracy-Dos Palos area includes about 1,800 square miles on the northwest side of the San Joaquin Valley. The Tulare Formation of Pliocene and Pleistocene age, terrace deposits of Pleistocene age, and alluvium and flood-basin deposits of Pleistocene and Holocene age constitute the fresh ground-water reservoir Pre-Tertiary and Tertiary sedimentary and crystalline rocks, undifferentiated, underlie the valley and yield saline water. Hydrologically most important, the Tulare Formation is divided into a lower water-bearing zone confined by the Corcoran Clay Member and an upper zone that is confined, semiconfined, and unconfined in different parts of the area. Alluvium and flood-basin deposits are included in the upper zone. Surficial alluvium and flood-basin deposits contain a shallow water-bearing zone. Lower zone wells were flowing in 1908, but subsequent irrigation development caused head declines and land subsidence. Overdraft in both zones ended in 1951 with import of surface water. Bicarbonate water flows into the area from the Sierra Nevada and Diablo Range. Diablo Range water is higher in sulfate, chloride, and dissolved solids. Upper zone water averages between 400 and 1,200 mg/l (milligrams per liter) dissolved solids and water hardness generally exceeds 180 mg/l as calcium carbonate. Nitrate, fluoride, iron, and boron occur in excessive concentrations in water from some wells. Dissolved constituents in lower zone water generally are sodium chloride and sodium sulfate with higher dissolved solids concentration than water from the upper zone. The foothills of the Diablo Range provide favorable conditions for artificial recharge, but shallow water problems plague about 50 percent of the area and artificial recharge is undesirable at this time.

Planktonic foraminifers and radiolarians from the Coniacian-santonian deposits of the Mt. Ak-Kaya, Crimean Mountains, Ukraine

NASA Astrophysics Data System (ADS)

Korchagin, O. A.; Bragina, L. G.; Bragin, N. Yu.

2012-02-01

The first data on the distribution of planktonic foraminifers and radiolarians in the Mt. Ak-Kaya section, the central Crimean Mountains, are considered. According to the analyzed distribution of foraminifers, the Upper Cretaceous deposits of the section are subdivided into three biostratigraphic units: the Marginotruncana austinensis-Globotruncana desioi (presumably upper Coniacian), Sigalia carpatica (uppermost Coniacian-lower Santonian), and Contusotruncana fornicata-Marginotruncana marginata (upper Santonian) beds. Subdivisions substantiated by distribution of radiolarians are the Alievium praegallowayi-Crucella plana (upper Coniacian-lower Santonian), Alievium gallowayi-Crucella espartoensis (the upper Santonian excluding its uppermost part), and Dictyocephalus (Dictyocryphalus) (?) legumen-Spongosaturninus parvulus (the uppermost Santonian) beds. The Contusotruncana fornicata-Marginotruncana marginata Beds are concurrent to the middle part of the Marsupites laevigatus Zone coupled with the Marsupites testudinarius Zone (the uppermost Santonian). The Alievium gallowayi-Crucella espartoensis Beds are correlative with the upper part of the Alievium gallowayi Zone in the Californian radiolarian zonation. The cooccurring assemblages of planktonic foraminifers and radiolarians provide a possibility to correlate the Coniacian-Santonian deposits within the Crimea-Caucasus region.

Hazardous Waste Cleanup: Military Ocean Terminal in Bayonne, New Jersey

EPA Pesticide Factsheets

The Military Ocean Terminal Bayonne (MOTBY) is a 652 acre, approximately 1/3-mile wide, 2-mile long, manmade peninsula that extends into the upper New York Harbor. It is located on Port Terminal Road adjacent to (west of) the City of Bayonne. Site use as

Results of coalbed-methane drilling, Mylan Park, Monongalia County, West Virginia: Chapter G.3 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Ruppert, Leslie F.; Fedorko, Nick; Warwick, Peter D.; Grady, William C.; Britton, James Q.; Schuller, William A.; Crangle, Robert D.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

High-pressure carbon-dioxide adsorption isotherms were measured on composite coal samples of the Upper Kittanning coal bed and the Middle Kittanning and Clarion coal zones. Assuming that the reservoir pressure in the Mylan Park coals is equivalent to the normal hydrostatic pressure, the estimated maximum carbon-dioxide adsorption pressures range from a low of about 300 pounds per square inch (lb/in2 ) in coals from the Clarion coal zone to 500 lb/in2 for coals from the Upper Kittanning coal bed. The estimated maximum methane adsorption isotherms show that the coals from the Upper Kittanning coal bed and the Middle Kittanning coal zone are undersaturated in methane, but coals from the Clarion coal zone are close to saturation.

Upper crustal structure beneath East Java from ambient noise tomography: A preliminary result

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martha, Agustya Adi; Graduate Research on Earthquakes and Active Tectonics, Institut Teknologi Bandung, Bandung; Widiyantoro, Sri

East Java has a fairly complex geological structure. Physiographically East Java can be divided into three zones, i.e. the Southern Mountains zone in the southern part, the Kendeng zone in the middle part, and the Rembang zone in the northern part. Most of the seismic hazards in this region are due to processes in the upper crust. In this study, the Ambient Noise Tomography (ANT) method is used to image the upper crustal structure beneath East Java. We have used seismic waveform data recorded by 8Meteorological, Climatological and Geophysical Agency (BMKG) stationary seismographic stations and 16 portable seismographs installed formore » 2 to 8 weeks. The data were processed to obtain waveforms fromnoise cross-correlation between pairs of seismographic stations. Our preliminary results indicate that the Kendeng zone, an area of low gravity anomaly, is associated with a low velocity zone. On the other hand, the southern mountain range, which has a high gravity anomaly, is related to a high velocity anomaly as shown by our tomographic images.« less

Hydrogeology, water quality, and water-supply potential of the Lower Floridan Aquifer, coastal Georgia, 1999-2002

USGS Publications Warehouse

Falls, W. Fred; Harrelson, Larry G.; Conlon, Kevin J.; Petkewich, Matthew D.

2005-01-01

The hydrogeology and water quality of the upper permeable and Fernandina permeable zones of the Lower Floridan aquifer were studied at seven sites in the 24-county study area encompassed by the Georgia Coastal Sound Science Initiative. Although substantially less than the Upper Floridan aquifer in coastal Georgia, transmissivities for the Lower Floridan aquifer are in the same range as other water-supply aquifers in Georgia and South Carolina and could meet the needs of public drinking-water supply. Water of the upper permeable zone of the Lower Floridan aquifer exceeds the Federal secondary drinking-water standards for sulfate and total dissolved solids at most coastal Georgia sites and the Federal secondary drinking-water standard for chloride at the Shellman Bluff site. The top of the Lower Floridan aquifer correlates within 50 feet of the previously reported top, except at the St Simons Island site where the top is more than 80 feet higher. Based on the hydrogeologic characteristics, the seven sites are divided into the northern sites at Shellman Bluff, Richmond Hill, Pembroke, and Pineora; and southern sites at St Marys, Brunswick, and St Simons Island. At the northern sites, the Lower Floridan aquifer does not include the Fernandina permeable zone, is thinner than the overlying Upper Floridan aquifer, and consists of only strata of the middle Eocene Avon Park Formation. Transmissivities in the Lower Floridan aquifer are 8,300 feet squared per day at Richmond Hill and 6,000 feet squared per day at Shellman Bluff, generally one tenth the transmissivity of the Upper Floridan aquifer at these sites. At the southern sites, the upper permeable zone of the Lower Floridan aquifer is thicker than the Upper Floridan aquifer and consists of porous limestone and dolomite interbedded with nonporous strata of the middle Eocene Avon Park and early Eocene Oldsmar Formations. Transmissivities for the upper permeable zone of the Lower Floridan aquifer are 500 feet squared per day at the St Simons Island site and 13,000 feet squared per day at the St Marys site. The Lower Floridan aquifer at the Brunswick and St Marys sites includes the Fernandina permeable zone, which consists of saltwater-bearing dolomite. Hydrographs of Coastal Sound Science Initiative wells and other nearby wells open to the Upper Floridan aquifer, and the upper permeable and Fernandina permeable zones of the Lower Floridan aquifer have similar trends. Water levels in wells open to the Upper and Lower Floridan aquifers are below land surface at the northern sites and the St Simons Island site, and above land surface at the Brunswick and St Marys sites, as of January 1, 2004. Freshwater is present in the Lower Floridan aquifer at Pineora, Pembroke, and St Marys, and from 1,259 to 1,648 feet below land surface at Brunswick. Slightly saline water is present in the Lower Floridan aquifer at Richmond Hill, Shellman Bluff, St Simons Island, and from 1,679 to 1,970 feet below land surface in well 34H495 at Brunswick. The upper permeable zone of the Lower Floridan aquifer contains bicarbonate water at the Pembroke site, sulfate-bicarbonate water at the Brunswick site, and sulfate water at the St Simons Island, Shellman Bluff, St Marys, and Richmond Hill sites. The bicarbonate, sulfate-bicarbonate, and sulfate waters are saturated relative to calcite and dolomite, and undersaturated with gypsum and anhydrite. The Fernandina permeable zone in well 34H495 includes moderately saline water, very saline water, and brine. The Fernandina permeable zone of the Lower Floridan aquifer beneath downtown Brunswick contains chloride water that is slightly undersaturated to saturated with gypsum and anhydrite. Concentrations of total dissolved solids, sulfate, and chloride exceeded the Federal secondary drinking-water standards. The chloride-contaminated plumes beneath downtown Brunswick would require at least a 12- to 20-percent contribution of very saline water from the Fernandi

Imaging the crustal magma sources beneath Mauna Loa and Kilauea volcanoes, Hawaii

USGS Publications Warehouse

Okubo, Paul G.; Benz, Harley M.; Chouet, Bernard A.

1997-01-01

Three-dimensional seismic P-wave traveltime tomography is used to image the magma sources beneath Mauna Loa and Kilauea volcanoes, Hawaii. High-velocity bodies (>6.4 km/s) in the upper 9 km of the crust beneath the summits and rift zones of the volcanoes correlate with zones of high magnetic intensities and are interpreted as solidified gabbro-ultramafic cumulates from which the surface volcanism is derived. The proximity of these high-velocity features to the rift zones is consistent with a ridge-spreading model of the volcanic flank. Southeast of the Hilina fault zone, along the south flank of Kilauea, low-velocity material (<6.0 km/s) is observed extending to depths of 9–11 km, indicating that the Hilina fault may extend possibly as deep as the basal decollement. Along the southeast flank of Mauna Loa, a similar low-velocity zone associated with the Kaoiki fault zone is observed extending to depths of 6–8 km. These two upper crustal low-velocity zones suggest common stages in the evolution of the Hawaiian shield volcanoes in which these fault systems are formed as a result of upper crustal deformation in response to magma injection within the volcanic edifice.

The NH2-terminal and COOH-terminal fragments of dentin matrix protein 1 (DMP1) localize differently in the compartments of dentin and growth plate of bone.

PubMed

Maciejewska, Izabela; Cowan, Cameron; Svoboda, Kathy; Butler, William T; D'Souza, Rena; Qin, Chunlin

2009-02-01

Multiple studies have shown that dentin matrix protein 1 (DMP1) is essential for bone and dentin mineralization. After post-translational proteolytic cleavage, DMP1 exists within the extracellular matrix of bone and dentin as an NH2-terminal fragment, a COOH-terminal fragment, and the proteoglycan form of the NH2-terminal fragment (DMP1-PG). To begin to assess the biological function of each fragment, we evaluated the distribution of both fragments in the rat tooth and bone using antibodies specific to the NH2-terminal and COOH-terminal regions of DMP1 and confocal microscopy. In rat first molar organs, the NH2-terminal fragment localized to predentin, whereas the COOH-terminal fragment was mainly restricted to mineralized dentin. In the growth plate of bone, the NH2-terminal fragment appeared in the proliferation and hypertrophic zones, whereas the COOH-terminal fragment occupied the ossification zone. Forster resonance energy transfer analysis showed colocalization of both fragments of DMP1 in odontoblasts and predentin, as well as hypertrophic chondrocytes within the growth plates of bone. The biochemical analysis of bovine teeth showed that predentin is rich in DMP1-PG, whereas mineralized dentin primarily contains the COOH-terminal fragment. We conclude that the differential patterns of expression of NH2-terminal and COOH-terminal fragments of DMP1 reflect their potentially distinct roles in the biomineralization of dentin and bone matrices.

Hanging canyons of Haida Gwaii, British Columbia, Canada: Fault-control on submarine canyon geomorphology along active continental margins

NASA Astrophysics Data System (ADS)

Harris, Peter T.; Barrie, J. Vaughn; Conway, Kim W.; Greene, H. Gary

2014-06-01

Faulting commonly influences the geomorphology of submarine canyons that occur on active continental margins. Here, we examine the geomorphology of canyons located on the continental margin off Haida Gwaii, British Columbia, that are truncated on the mid-slope (1200-1400 m water depth) by the Queen Charlotte Fault Zone (QCFZ). The QCFZ is an oblique strike-slip fault zone that has rates of lateral motion of around 50-60 mm/yr and a small convergent component equal to about 3 mm/yr. Slow subduction along the Cascadia Subduction Zone has accreted a prism of marine sediment against the lower slope (1500-3500 m water depth), forming the Queen Charlotte Terrace, which blocks the mouths of submarine canyons formed on the upper slope (200-1400 m water depth). Consequently, canyons along this margin are short (4-8 km in length), closely spaced (around 800 m), and terminate uniformly along the 1400 m isobath, coinciding with the primary fault trend of the QCFZ. Vertical displacement along the fault has resulted in hanging canyons occurring locally. The Haida Gwaii canyons are compared and contrasted with the Sur Canyon system, located to the south of Monterey Bay, California, on a transform margin, which is not blocked by any accretionary prism, and where canyons thus extend to 4000 m depth, across the full breadth of the slope.

OVERVIEW OF UPPER TRAM TERMINAL, TRAM TRESTLE, AND PRIMARY ORE ...

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

OVERVIEW OF UPPER TRAM TERMINAL, TRAM TRESTLE, AND PRIMARY ORE BIN, LOOKING NORTHEAST. REMAINS OF A BLACKSMITH'S FORGE AND WORK CAN BE SEEN JUST BELOW THE ORE BIN (SEE CA-291-32 FOR DETAIL). ROCK FOUNDATIONS LOCATED JUST ABOVE THE ORE BIN AND ALONG THE FIRST RIDGELINE ARE TENT PADS. SEE CA-291-24 FOR IDENTICAL B&W NEGATIVE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

OVERVIEW OF UPPER TRAM TERMINAL, TRAM TRESTLE, AND PRIMARY ORE ...

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

OVERVIEW OF UPPER TRAM TERMINAL, TRAM TRESTLE, AND PRIMARY ORE BIN, LOOKING NORTHEAST. REMAINS OF A BLACKSMITH'S FORGE AND WORK CAN BE SEEN JUST BELOW THE ORE BIN (SEE CA-291-32 FOR DETAIL). ROCK FOUNDATIONS LOCATED JUST ABOVE THE ORE BIN AND ALONG THE FIRST RIDGELINE ARE TENT PADS. SEE CA-291-49 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

77 FR 52681 - Reorganization and Expansion of Foreign-Trade Zone 87 Lake Charles, LA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-30

... Foreign-Trade Zone 87 Lake Charles, LA Pursuant to its authority under the Foreign-Trade Zones Act of June 18, 1934, as amended (19 U.S.C. 81a-81u), the Foreign-Trade Zones Board (the Board) adopts the following Order: Whereas, the Lake Charles Harbor & Terminal District, grantee of Foreign-Trade Zone 87...

Multiscale Architecture of a Subduction Complex and Insight into Large-scale Material Movement in Subduction Systems

NASA Astrophysics Data System (ADS)

Wakabayashi, J.

2014-12-01

The >1000 km by >100 km Franciscan complex of California records >100 Ma of subduction history that terminated with conversion to a transform margin. It affords an ideal natural laboratory to study the rock record of subduction-interface and related processes exhumed from 10-70 km. The Franciscan comprises coherent and block-in-matrix (mélange) units forming a nappe stack that youngs structurally downward in accretion age, indicating progressive subduction accretion. Gaps in accretion ages indicate periods of non-accretion or subduction erosion. The Franciscan comprises siliciclastic trench fill rocks, with lesser volcanic and pelagic rocks and serpentinite derived from the downgoing plate, as well as serpentinite and felsic-intermediate igneous blocks derived as detritus from the upper plate. The Franciscan records subduction, accretion, and metamorphism (including HP), spanning an extended period of subduction, rather than a single event superimposed on pre-formed stratigraphy. Melanges (serpentinite and siliciclastic matrix) with exotic blocks, that include high-grade metamorphic blocks, and felsic-intermediate igneous blocks from the upper plate, are mostly/entirely of sedimentary origin, whereas block-in-matrix rocks formed by tectonism lack exotic blocks and comprise disrupted ocean plate stratigraphy. Mélanges with exotic blocks are interbedded with coherent sandstones. Many blocks-in-melange record two HP burial events followed by surface exposure, and some record three. Paleomegathrust horizons, separating nappes accreted at different times, appear restricted to narrow fault zones of <100's of m thickness, and <50 m in best constrained cases; these zones lack exotic blocks. Large-scale displacements, whether paleomegathrust horizons, shortening within accreted nappes, or exhumation structures, are accommodated by discrete faults or narrow shear zones, rather than by significant penetrative strain. Exhumation of Franciscan HP units, both coherent and mélange, was accommodated by significant extension of the overlying plate, and possibly extension within the subduction complex, with cross-sectional extrusion, and like subduction burial, took place at different times.

33 CFR 165.T0704 - Safety Zone: Savannah River, Savannah, Georgia.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: Savannah River....T0704 Safety Zone: Savannah River, Savannah, Georgia. (a) Location. The following area is a safety zone: Two hundred foot radius around Garden City Terminal, approximate position 32 degrees 8 minutes, N, 81...

Can compliant fault zones be used to measure absolute stresses in the upper crust?

NASA Astrophysics Data System (ADS)

Hearn, E. H.; Fialko, Y.

2009-04-01

Geodetic and seismic observations reveal long-lived zones with reduced elastic moduli along active crustal faults. These fault zones localize strain from nearby earthquakes, consistent with the response of a compliant, elastic layer. Fault zone trapped wave studies documented a small reduction in P and S wave velocities along the Johnson Valley Fault caused by the 1999 Hector Mine earthquake. This reduction presumably perturbed a permanent compliant structure associated with the fault. The inferred changes in the fault zone compliance may produce a measurable deformation in response to background (tectonic) stresses. This deformation should have the same sense as the background stress, rather than the coseismic stress change. Here we investigate how the observed deformation of compliant zones in the Mojave Desert can be used to constrain the fault zone structure and stresses in the upper crust. We find that gravitational contraction of the coseismically softened zones should cause centimeters of coseismic subsidence of both the compliant zones and the surrounding region, unless the compliant fault zones are shallow and narrow, or essentially incompressible. We prefer the latter interpretation because profiles of line of sight displacements across compliant zones cannot be fit by a narrow, shallow compliant zone. Strain of the Camp Rock and Pinto Mountain fault zones during the Hector Mine and Landers earthquakes suggests that background deviatoric stresses are broadly consistent with Mohr-Coulomb theory in the Mojave upper crust (with μ ≥ 0.7). Large uncertainties in Mojave compliant zone properties and geometry preclude more precise estimates of crustal stresses in this region. With improved imaging of the geometry and elastic properties of compliant zones, and with precise measurements of their strain in response to future earthquakes, the modeling approach we describe here may eventually provide robust estimates of absolute crustal stress.

Meta-omic signatures of microbial metal and nitrogen cycling in marine oxygen minimum zones

PubMed Central

Glass, Jennifer B.; Kretz, Cecilia B.; Ganesh, Sangita; Ranjan, Piyush; Seston, Sherry L.; Buck, Kristen N.; Landing, William M.; Morton, Peter L.; Moffett, James W.; Giovannoni, Stephen J.; Vergin, Kevin L.; Stewart, Frank J.

2015-01-01

Iron (Fe) and copper (Cu) are essential cofactors for microbial metalloenzymes, but little is known about the metalloenyzme inventory of anaerobic marine microbial communities despite their importance to the nitrogen cycle. We compared dissolved O2, NO3−, NO2−, Fe and Cu concentrations with nucleic acid sequences encoding Fe and Cu-binding proteins in 21 metagenomes and 9 metatranscriptomes from Eastern Tropical North and South Pacific oxygen minimum zones and 7 metagenomes from the Bermuda Atlantic Time-series Station. Dissolved Fe concentrations increased sharply at upper oxic-anoxic transition zones, with the highest Fe:Cu molar ratio (1.8) occurring at the anoxic core of the Eastern Tropical North Pacific oxygen minimum zone and matching the predicted maximum ratio based on data from diverse ocean sites. The relative abundance of genes encoding Fe-binding proteins was negatively correlated with O2, driven by significant increases in genes encoding Fe-proteins involved in dissimilatory nitrogen metabolisms under anoxia. Transcripts encoding cytochrome c oxidase, the Fe- and Cu-containing terminal reductase in aerobic respiration, were positively correlated with O2 content. A comparison of the taxonomy of genes encoding Fe- and Cu-binding vs. bulk proteins in OMZs revealed that Planctomycetes represented a higher percentage of Fe genes while Thaumarchaeota represented a higher percentage of Cu genes, particularly at oxyclines. These results are broadly consistent with higher relative abundance of genes encoding Fe-proteins in the genome of a marine planctomycete vs. higher relative abundance of genes encoding Cu-proteins in the genome of a marine thaumarchaeote. These findings highlight the importance of metalloenzymes for microbial processes in oxygen minimum zones and suggest preferential Cu use in oxic habitats with Cu > Fe vs. preferential Fe use in anoxic niches with Fe > Cu. PMID:26441925

Meta-omic signatures of microbial metal and nitrogen cycling in marine oxygen minimum zones.

PubMed

Glass, Jennifer B; Kretz, Cecilia B; Ganesh, Sangita; Ranjan, Piyush; Seston, Sherry L; Buck, Kristen N; Landing, William M; Morton, Peter L; Moffett, James W; Giovannoni, Stephen J; Vergin, Kevin L; Stewart, Frank J

2015-01-01

Iron (Fe) and copper (Cu) are essential cofactors for microbial metalloenzymes, but little is known about the metalloenyzme inventory of anaerobic marine microbial communities despite their importance to the nitrogen cycle. We compared dissolved O2, NO[Formula: see text], NO[Formula: see text], Fe and Cu concentrations with nucleic acid sequences encoding Fe and Cu-binding proteins in 21 metagenomes and 9 metatranscriptomes from Eastern Tropical North and South Pacific oxygen minimum zones and 7 metagenomes from the Bermuda Atlantic Time-series Station. Dissolved Fe concentrations increased sharply at upper oxic-anoxic transition zones, with the highest Fe:Cu molar ratio (1.8) occurring at the anoxic core of the Eastern Tropical North Pacific oxygen minimum zone and matching the predicted maximum ratio based on data from diverse ocean sites. The relative abundance of genes encoding Fe-binding proteins was negatively correlated with O2, driven by significant increases in genes encoding Fe-proteins involved in dissimilatory nitrogen metabolisms under anoxia. Transcripts encoding cytochrome c oxidase, the Fe- and Cu-containing terminal reductase in aerobic respiration, were positively correlated with O2 content. A comparison of the taxonomy of genes encoding Fe- and Cu-binding vs. bulk proteins in OMZs revealed that Planctomycetes represented a higher percentage of Fe genes while Thaumarchaeota represented a higher percentage of Cu genes, particularly at oxyclines. These results are broadly consistent with higher relative abundance of genes encoding Fe-proteins in the genome of a marine planctomycete vs. higher relative abundance of genes encoding Cu-proteins in the genome of a marine thaumarchaeote. These findings highlight the importance of metalloenzymes for microbial processes in oxygen minimum zones and suggest preferential Cu use in oxic habitats with Cu > Fe vs. preferential Fe use in anoxic niches with Fe > Cu.

78 FR 74009 - Safety Zone; Nike Fireworks, Upper New York Bay, Ellis Island, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-10

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2013-0962] Safety Zone; Nike Fireworks, Upper New York Bay, Ellis Island, NY AGENCY: Coast Guard, DHS. ACTION: Notice of... published in the Federal Register on November 9, 2011 (76 FR 69614). [[Page 74010

Evolution of crustal stress, pressure and temperature around shear zones during orogenic wedge formation: a 2D thermo-mechanical numerical study

NASA Astrophysics Data System (ADS)

Markus Schmalholz, Stefan; Jaquet, Yoann

2016-04-01

We study the formation of an orogenic wedge during lithospheric shortening with 2D numerical simulations. We consider a viscoelastoplastic rheology, thermo-mechanical coupling by shear heating and temperature-dependent viscosities, gravity and erosion. In the initial model configuration there is either a lateral temperature variation at the model base or a lateral variation in crustal thickness to generate slight stress variations during lithospheric shortening. These stress variations can trigger the formation of shear zones which are caused by thermal softening associated with shear heating. We do not apply any kind of strain softening, such as reduction of friction angle with progressive plastic strain. The first major shear zone that appears during shortening crosscuts the entire crust and initiates the asymmetric subduction/underthrusting of mainly the mechanically strong lower crust. After some deformation, the first shear zone in the upper crust is abandoned, the deformation propagates towards the foreland and a new shear zone forms only in the upper crust. The shear zone propagation occurs several times where new shear zones form in the upper crust and the mechanically strong top of the lower crust acts as detachment horizon. We calculate the magnitudes of the maximal and minimal principal stresses and of the mean stress (or dynamic pressure), and we record also the temperature for several marker points in the upper and lower crust. We analyse the evolution of stresses and temperature with burial depth and time. Deviatoric stresses (half the differential stress) in the upper crust are up to 200 MPa and associated shear heating in shear zones ranges between 40 - 80 °C. Lower crustal rocks remain either at the base of the orogenic wedge at depths of around 50 km or are subducted to depths of up to 120 km, depending on their position when the first shear zone formed. Largest deviatotric stresses in the strong part of the lower crust are about 1000 MPa and maximal shear heating in shear zones is approximately 200 °C. Marker points can migrate through the main shear zone in the lower crust which remains active throughout lithospheric shortening. Some pressure-temperature paths show an anti-clockwise evolution. The impact of various model parameters on the results is discussed as well as applications of the results to geological data.

Vesicular komatiites, 3.5-Ga Komati Formation, Barberton Greenstone Belt, South Africa: inflation of submarine lavas and origin of spinifex zones

NASA Astrophysics Data System (ADS)

Dann, Jesse

2001-08-01

Komatiites of the 3.5-Ga Komati Formation are ultramafic lavas (>23% MgO) erupted in a submarine, lava plain environment. Newly discovered vesicular komatiites have vesicular upper crusts disrupted by synvolcanic structures that are similar to inflation-related structures of modern lava flows. Detailed outcrop maps reveal flows with upper vesicular zones, 2-15 m thick, which were (1) rotated by differential inflation, (2) intruded by dikes from the interior of the flow, (3) extended, forming a flooded graben, and/or (4) entirely engulfed. The largest inflated structure is a tumulus with 20 m of surface relief, which was covered by a compound flow unit of spinifex flow lobes. The lava that inflated and rotated the upper vesicular crust did not vesiculate, but crystallized as a thick spinifex zone with fist-size skeletal olivine. Instead of representing rapidly cooled lava, the spinifex zone cooled slowly beneath an insulating upper crust during inflation. Overpressure of the inflating lava may have inhibited vesiculation. This work describes the oldest vesicular komatiites known, illustrates the first field evidence for inflated structures in komatiite flows, proposes a new factor in the development of spinifex zones, and concludes that the inflation model is useful for understanding the evolution of komatiite submarine flow fields.

Trace fossils and sedimentology of a Late Cretaceous Progradational Barrier Island sequence: Bearpaw and Horseshoe Canyon Formations, Dorothy, Alberta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saunders, T.D.; Pemberton, A.G.; Ranger, M.J.

A well-exposed example of a regressive barrier island succession crops out in the Alberta badlands along the Red Deer River Valley. In the most landward (northwestern) corner of the study area, only shallow-water and subaerial deposits are represented and are dominated by tidal inlet related facies. Seaward (southeast), water depth increases and the succession is typified by open-marine beach to offshore-related facies arranged in coarsening-upward progradational sequence. Detailed sedimentologic and ichnologic analyses of this sequence have allowed for its division into three distinct environmental zones (lower, middle, and upper). The lower zone comprises a laterally diverse assemblage of storm-influenced, lowermore » shoreface through offshore deposits. Outcrop in the northeast is dominated by thick beds of hummocky and/or swaley cross-stratified storm sand. In the southeast, storm events have only minor influence. This lower zone contains a wide diversity of well-preserved trace fossils whose distribution appears to have been influenced by gradients in wave energy, bottom stagnation, and the interplay of storm and fair-weather processes. The middle zone records deposition across an upper shoreface environment. Here, horizontal to low-angle bedding predominates, with interspersed sets of small- and large-scale cross-bedding increasing toward the top. A characteristic feature of the upper part of this zone is the lack of biogenic structures suggesting deposition in an exposed high-energy surf zone. The upper zone records intertidal to supratidal progradation of the shoreline complex. Planar-laminated sandstone forms a distinct foreshore interval above which rhizoliths and organic material become increasingly abundant, marking transition to the backshore. A significant feature of this zone is the occurrence of an intensely bioturbated interval toward the top of the foreshore.« less

Monolithic tandem solar cell

DOEpatents

Wanlass, Mark W.

1991-01-01

A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, and (c) a second photoactive subcell on the first subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. The solar cell can be provided as a two-terminal device or a three-terminal device.

Emplacement model of obsidian-rhyolite magma deduced from complete internal section of the Akaishiyama lava, Shirataki, northern Hokkaido, Japan

NASA Astrophysics Data System (ADS)

Wada, K.; Sano, K.

2016-12-01

Simultaneously explosive and effusive eruptions of silicic magmas has shed light on the vesiculation and outgassing history of ascending magmas in the conduit and emplacement model of obsidian-rhyolite lavas (Castro et al., 2014; Shipper et al, 2013). As well as the knowledge of newly erupted products such as 2008-2009 Chaitén and 2011-2012 Cordón Caule eruptions, field and micro-textural evidences of well-exposed internal structure of obsidian-rhyolite lava leads to reveal eruption processes of silicic magmas. The Shirataki monogenetic volcano field, 2.2 million year age, northern Hokkaido, Japan, contains many outcrops of obsidian and vesiculated rhyolite zones (SiO2=76.7-77.4 wt.%). Among their outcrops, Akaishiyama lava shows good exposures of internal sections from the top to the bottom along the Kyukasawa valley with thickness of about 190 meters, showing the symmetrical structure comprising a upper clastic zone (UCZ; 5m thick), an upper dense obsidian zone (UDO; 15m), an upper banded obsidian zone (UBO; 70-80m), a central rhyolite zone (CR; 65m), a lower banded obsidian zone (LBO; 15m), a lower dense obsidian zone (LDO; 20m), and a lower clastic zone (LCZ; 3m). The upper banded obsidian zone is characterized by existence of spherulite concentration layers with tuffisite veins and rhyolite enclaves. Spherulites consisting of albite, cristobalaite and obsidian glass, are clustered in the dense obsidian. Tuffisite veins show brecciated obsidians in tuffaceous matrix, showing an outgassing path during the emplacement of obsidian lava. Perpendicular dip of spherulite parallel rows indicates the banded zone itself was the domain of vent area. From the observation of these occurrences in the internal section and rock texture, we show the qualitative formation model of Shirataki obsidian-rhyolite lava.

Clarinet (CLA-1), a novel active zone protein required for synaptic vesicle clustering and release

PubMed Central

Nelson, Jessica; Richmond, Janet E; Colón-Ramos, Daniel A; Shen, Kang

2017-01-01

Active zone proteins cluster synaptic vesicles at presynaptic terminals and coordinate their release. In forward genetic screens, we isolated a novel Caenorhabditis elegans active zone gene, clarinet (cla-1). cla-1 mutants exhibit defects in synaptic vesicle clustering, active zone structure and synapse number. As a result, they have reduced spontaneous vesicle release and increased synaptic depression. cla-1 mutants show defects in vesicle distribution near the presynaptic dense projection, with fewer undocked vesicles contacting the dense projection and more docked vesicles at the plasma membrane. cla-1 encodes three isoforms containing common C-terminal PDZ and C2 domains with homology to vertebrate active zone proteins Piccolo and RIM. The C-termini of all isoforms localize to the active zone. Specific loss of the ~9000 amino acid long isoform results in vesicle clustering defects and increased synaptic depression. Our data indicate that specific isoforms of clarinet serve distinct functions, regulating synapse development, vesicle clustering and release. PMID:29160205

Ichthyofauna as bioindicator of environmental quality in an industrial district in the amazon estuary, Brazil.

PubMed

Viana, A P; Lucena Frédou, F

2014-05-01

The objective of the present study was to describe the ecological status of ichthyofauna in an industrial district (Pará river, Amazon estuary), through the use of different environmental descriptors. To evaluate the impacts of the industrial area and cargo terminal, three areas were considered: Zone 1 (maximum impact), Zone 2 (median impact) and Zone 3 (low impact). A total of 77 species were captured. Differences in the composition of the ichthyofauna were recorded between Zones and environments (main channel and tidal channel). The ecological indices revealed clear evidence of the impact of the industrial hub and cargo terminal on the fish communities. In Zone 1, there was a reduction in the number of feeding groups (in the main channel) and larger fish and the Shannon diversity index and Margalef's richness were also significantly lower. The multivariate analysis separated the different Zones clearly into three groups, indicating marked differences in the levels of contamination in the different parts of the study area.

Rheological structure of the lithosphere in plate boundary strike-slip fault zones

NASA Astrophysics Data System (ADS)

Chatzaras, Vasileios; Tikoff, Basil; Kruckenberg, Seth C.; Newman, Julie; Titus, Sarah J.; Withers, Anthony C.; Drury, Martyn R.

2016-04-01

How well constrained is the rheological structure of the lithosphere in plate boundary strike-slip fault systems? Further, how do lithospheric layers, with rheologically distinct behaviors, interact within the strike-slip fault zones? To address these questions, we present rheological observations from the mantle sections of two lithospheric-scale, strike-slip fault zones. Xenoliths from ˜40 km depth (970-1100 ° C) beneath the San Andreas fault system (SAF) provide critical constraints on the mechanical stratification of the lithosphere in this continental transform fault. Samples from the Bogota Peninsula shear zone (BPSZ, New Caledonia), which is an exhumed oceanic transform fault, provide insights on lateral variations in mantle strength and viscosity across the fault zone at a depth corresponding to deformation temperatures of ˜900 ° C. Olivine recrystallized grain size piezometry suggests that the shear stress in the SAF upper mantle is 5-9 MPa and in the BPSZ is 4-10 MPa. Thus, the mantle strength in both fault zones is comparable to the crustal strength (˜10 MPa) of seismogenic strike-slip faults in the SAF system. Across the BPSZ, shear stress increases from 4 MPa in the surrounding rocks to 10 MPa in the mylonites, which comprise the core of the shear zone. Further, the BPSZ is characterized by at least one order of magnitude difference in the viscosity between the mylonites (1018 Paṡs) and the surrounding rocks (1019 Paṡs). Mantle viscosity in both the BPSZ mylonites and the SAF (7.0ṡ1018-3.1ṡ1020 Paṡs) is relatively low. To explain our observations from these two strike-slip fault zones, we propose the "lithospheric feedback" model in which the upper crust and lithospheric mantle act together as an integrated system. Mantle flow controls displacement and the upper crust controls the stress magnitude in the system. Our stress data combined with data that are now available for the middle and lower crustal sections of other transcurrent fault systems support the prediction for constant shear strength (˜10 MPa) throughout the lithosphere; the stress magnitude is controlled by the shear strength of the upper crustal faults. Fault rupture in the upper crust induces displacement rate loading of the upper mantle, which in turn, causes strain localization in the mantle shear zone beneath the strike-slip fault. Such forced localization leads to higher stresses and strain rates in the shear zone compared to the surrounding rocks. Low mantle viscosity within the shear zone is critical for facilitating mantle flow, which induces widespread crustal deformation and displacement loading. The lithospheric feedback model suggests that strike-slip fault zones are not mechanically stratified in terms of shear stress, and that it is the time-dependent interaction of the different lithospheric layers - rather than their relative strengths - that governs the rheological behavior of the plate boundary, strike-slip fault zones.

Adhesive Bubble Removal Method and Apparatus for Fiber Optic Applications

NASA Technical Reports Server (NTRS)

Kolasinski, John R. (Inventor)

2001-01-01

An assembly for supporting a fiber optic termination or connector in a centrifuge and comprising a cylindrical body member having a top portion adapted to receive the ferrule body portion of a fiber optic termination or connector and a bottom portion for receiving a cylindrical piston/sealing unit is presented. The piston portion of the piston/sealing unit includes a compressible tip which is adapted to a butt up against the outer end of the ferrule body portion of the fiber optic termination or connector. A cylindrical end cap fits over the upper end of the body member for holding the fiber optic termination in place on the body member and causing a seal to be formed between the termination or connector and the upper portion of the body member adjacent the compressible tip of the plunger. The parts, when fitted together, are placed in a centrifuge which is operated for a predetermined spin cycle, so as to cause any bubbles in the uncured liquid adhesive to be vented outwardly from the termination through the end cap. Subsequent removal of the fiber optic termination or connector from the centrifuge and assembly is "bubble free" and ready to be joined with an optical fiber which is inserted in the ferrule end of the termination or connector.

Adhesive bubble removal method and apparatus for fiber applications

NASA Technical Reports Server (NTRS)

Kolasinski, John R. (Inventor)

2005-01-01

An assembly for supporting a fiber optic termination or connector in a centrifuge and comprising a cylindrical body member having a top portion adapted to receive the ferrule body portion of a fiber optic termination or connector and a bottom portion for receiving a cylindrical piston/sealing unit. The piston portion of the piston/sealing unit includes a compressible tip which is adapted to a butt up against the outer end of the ferrule body portion of the fiber optic termination or connector. A cylindrical end cap fits over the upper end of the body member for holding the fiber optic termination in place on the body member and causing a seal to be formed between the termination or connector and the upper portion of the body member adjacent the compressible tip of the plunger. The parts, when fitted together, are placed in a centrifuge which is operated for a predetermined spin cycle, so as to cause any bubbles in the uncured liquid adhesive to be vented outwardly from the termination through the end cap. Subsequent removal of the fiber optic termination or connector from the centrifuge and assembly is bubble free and ready to be joined with an optical fiber which is inserted in the ferrule end of the termination or connector.

Application of the Vienna Classification for Crohn's disease to a single clinician database of 877 patients.

PubMed

Freeman, H J

2001-02-01

An international working party at the World Congress of Gastroenterology held in Vienna, Austria from September 6 to 11, 1998 defined a classification for Crohn's disease based on patient age at diagnosis (eg, less than 40 years of age, 40 years of age or older), disease location (eg, terminal ileum, colon, ileocolon or upper gastrointestinal tract) and behaviour (eg, stricturing, penetrating). Disease location in the upper gastrointestinal tract was defined by disease being present proximal to the terminal ileum, regardless of terminal ileal or colon involvement. A 20-year, single clinician database of 877 patients from a university campus hospital was used, and comprised 492 women (56.1%) and 385 men (43.9%). Of these patients, 740 (84.4%) were diagnosed before age 40 years and 137 (15.6%) were diagnosed by 40 years of age or older. Disease was located in the terminal ileum alone in 222 patients (25.3%), colon alone in 238 patients (27.2%) and ileocolon in 304 patients (34.6%). Another 113 patients (13.1%) had disease in the upper gastrointestinal tract, usually with disease also in the terminal ileum (23 patients), colon (12 patients) or ileocolon (71 patients). Only seven of 877 patients had disease located in the upper gastrointestinal tract alone with no distal disease. Disease behaviour could be classified as nonstricturing and nonpenetrating in 256 patients (29.2%), stricturing in 294 patients (33.6%) and penetrating in 327 patients (37.2%). Of the 877 patients with Crohn's disease, 837 were white, 38 were Asian and two were black. In this tertiary care setting of a single clinician practice in a Canadian teaching hospital at the University of British Columbia, Crohn's disease predominantly affects women, and young adults with a high rate of stricturing and penetrating complications.

Modelling seasonal meltwater forcing of the velocity of land-terminating margins of the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Koziol, Conrad P.; Arnold, Neil

2018-03-01

Surface runoff at the margin of the Greenland Ice Sheet (GrIS) drains to the ice-sheet bed, leading to enhanced summer ice flow. Ice velocities show a pattern of early summer acceleration followed by mid-summer deceleration due to evolution of the subglacial hydrology system in response to meltwater forcing. Modelling the integrated hydrological-ice dynamics system to reproduce measured velocities at the ice margin remains a key challenge for validating the present understanding of the system and constraining the impact of increasing surface runoff rates on dynamic ice mass loss from the GrIS. Here we show that a multi-component model incorporating supraglacial, subglacial, and ice dynamic components applied to a land-terminating catchment in western Greenland produces modelled velocities which are in reasonable agreement with those observed in GPS records for three melt seasons of varying melt intensities. This provides numerical support for the hypothesis that the subglacial system develops analogously to alpine glaciers and supports recent model formulations capturing the transition between distributed and channelized states. The model shows the growth of efficient conduit-based drainage up-glacier from the ice sheet margin, which develops more extensively, and further inland, as melt intensity increases. This suggests current trends of decadal-timescale slowdown of ice velocities in the ablation zone may continue in the near future. The model results also show a strong scaling between average summer velocities and melt season intensity, particularly in the upper ablation area. Assuming winter velocities are not impacted by channelization, our model suggests an upper bound of a 25 % increase in annual surface velocities as surface melt increases to 4 × present levels.

Geophysical constraints on geodynamic processes at convergent margins: A global perspective

NASA Astrophysics Data System (ADS)

Artemieva, Irina; Thybo, Hans; Shulgin, Alexey

2016-04-01

Convergent margins, being the boundaries between colliding lithospheric plates, form the most disastrous areas in the world due to intensive, strong seismicity and volcanism. We review global geophysical data in order to illustrate the effects of the plate tectonic processes at convergent margins on the crustal and upper mantle structure, seismicity, and geometry of subducting slab. We present global maps of free-air and Bouguer gravity anomalies, heat flow, seismicity, seismic Vs anomalies in the upper mantle, and plate convergence rate, as well as 20 profiles across different convergent margins. A global analysis of these data for three types of convergent margins, formed by ocean-ocean, ocean-continent, and continent-continent collisions, allows us to recognize the following patterns. (1) Plate convergence rate depends on the type of convergent margins and it is significantly larger when, at least, one of the plates is oceanic. However, the oldest oceanic plate in the Pacific ocean has the smallest convergence rate. (2) The presence of an oceanic plate is, in general, required for generation of high-magnitude (M N 8.0) earthquakes and for generating intermediate and deep seismicity along the convergent margins. When oceanic slabs subduct beneath a continent, a gap in the seismogenic zone exists at depths between ca. 250 km and 500 km. Given that the seismogenic zone terminates at ca. 200 km depth in case of continent-continent collision, we propose oceanic origin of subducting slabs beneath the Zagros, the Pamir, and the Vrancea zone. (3) Dip angle of the subducting slab in continent-ocean collision does not correlate neither with the age of subducting oceanic slab, nor with the convergence rate. For ocean-ocean subduction, clear trends are recognized: steeply dipping slabs are characteristic of young subducting plates and of oceanic plates with high convergence rate, with slab rotation towards a near-vertical dip angle at depths below ca. 500 km at very high convergence rate. (4) Local isostasy is not satisfied at the convergent margins as evidenced by strong free air gravity anomalies of positive and negative signs. However, near-isostatic equilibrium may exist in broad zones of distributed deformation such as Tibet. (5) No systematic patterns are recognized in heat flow data due to strong heterogeneity of measured values which are strongly affected by hydrothermal circulation, magmatic activity, crustal faulting, horizontal heat transfer, and also due to low number of heat flow measurements across many margins. (6) Low upper mantle Vs seismic velocities beneath the convergent margins are restricted to the upper 150 km and may be related to mantle wedge melting which is confined to shallow mantle levels. Artemieva, I.M., Thybo, H., and Shulgin, A., 2015. Geophysical constraints on geodynamic processes at convergent margins: A global perspective. Gondwana Research, http://dx.doi.org/10.1016/j.gr.2015.06.010

7 CFR 25.607 - Suspension or termination of grant funds.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Suspension or termination of grant funds. 25.607 Section 25.607 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES AND ENTERPRISE COMMUNITIES Round II and Round IIS Grants § 25.607 Suspension or termination of grant funds. (a) Grants under...

7 CFR 25.607 - Suspension or termination of grant funds.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 1 2012-01-01 2012-01-01 false Suspension or termination of grant funds. 25.607 Section 25.607 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES AND ENTERPRISE COMMUNITIES Round II and Round IIS Grants § 25.607 Suspension or termination of grant funds. (a) Grants under...

7 CFR 25.607 - Suspension or termination of grant funds.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 1 2014-01-01 2014-01-01 false Suspension or termination of grant funds. 25.607 Section 25.607 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES AND ENTERPRISE COMMUNITIES Round II and Round IIS Grants § 25.607 Suspension or termination of grant funds. (a) Grants under...

7 CFR 25.607 - Suspension or termination of grant funds.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Suspension or termination of grant funds. 25.607 Section 25.607 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES AND ENTERPRISE COMMUNITIES Round II and Round IIS Grants § 25.607 Suspension or termination of grant funds. (a) Grants under...

7 CFR 25.607 - Suspension or termination of grant funds.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 1 2011-01-01 2011-01-01 false Suspension or termination of grant funds. 25.607 Section 25.607 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES AND ENTERPRISE COMMUNITIES Round II and Round IIS Grants § 25.607 Suspension or termination of grant funds. (a) Grants under...

49 CFR 372.223 - Consolidated governments.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Consolidated governments. 372.223 Section 372.223... ZONES, AND TERMINAL AREAS Commercial Zones § 372.223 Consolidated governments. The zone adjacent to, and commercially a part of a consolidated government within which transportation by motor vehicle, in interstate or...

49 CFR 372.223 - Consolidated governments.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Consolidated governments. 372.223 Section 372.223... ZONES, AND TERMINAL AREAS Commercial Zones § 372.223 Consolidated governments. The zone adjacent to, and commercially a part of a consolidated government within which transportation by motor vehicle, in interstate or...

49 CFR 372.223 - Consolidated governments.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Consolidated governments. 372.223 Section 372.223... ZONES, AND TERMINAL AREAS Commercial Zones § 372.223 Consolidated governments. The zone adjacent to, and commercially a part of a consolidated government within which transportation by motor vehicle, in interstate or...

49 CFR 372.223 - Consolidated governments.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Consolidated governments. 372.223 Section 372.223... ZONES, AND TERMINAL AREAS Commercial Zones § 372.223 Consolidated governments. The zone adjacent to, and commercially a part of a consolidated government within which transportation by motor vehicle, in interstate or...

49 CFR 372.223 - Consolidated governments.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Consolidated governments. 372.223 Section 372.223... ZONES, AND TERMINAL AREAS Commercial Zones § 372.223 Consolidated governments. The zone adjacent to, and commercially a part of a consolidated government within which transportation by motor vehicle, in interstate or...

Tethyan calpionellids in the Neuquén Basin (Argentine Andes), their significance in defining the Jurassic/Cretaceous boundary and pathways for Tethyan-Eastern Pacific connections

NASA Astrophysics Data System (ADS)

López-Martínez, Rafael; Aguirre-Urreta, Beatriz; Lescano, Marina; Concheyro, Andrea; Vennari, Verónica; Ramos, Victor A.

2017-10-01

The study of calpionellid distribution in the well-documented Las Loicas section of the Vaca Muerta Formation in the Neuquén Basin, Argentine Andes, allows the recognition of the upper part of the Crassicollaria Zone and the lower part of Calpionella Zone across the Jurassic/Cretaceous boundary. The Crassicollaria Zone, Colomi Subzone (Upper Tithonian) is composed of Calpionella alpina Lorenz, Crassicollaria colomi Doben, Crassicollaria parvula Remane, Crassicollaria massutiniana (Colom), Crassicollaria brevis Remane, Tintinnopsella remanei (Borza) and Tintinnopsella carpathica (Murgeanu and Filipescu). The Calpionella Zone, Alpina Subzone (Lower Berriasian) is indicated by the explosion of the small and globular form of Calpionella alpina dominating over very scarce Crassicollaria massutiniana. The FAD of Nannoconus wintereri can be clearly correlated with the upper part of Crassicollaria Zone and the FAD of Nannoconus kamptneri minor with the Calpionella Zone. Additional studies are necessary to establish a more detailed calpionellid biozonation and its correlation with other fossil groups. The present work confirms similar calpionellid bioevents in westernmost Tethys (Cuba and Mexico) and the Andean region, strengthening the Paleo-Pacific-Tethyan connections through the Hispanic Corridor already known from other fossil groups.

The Yudomian of Siberia, Vendian and Ediacaran systems of the International stratigraphic scale

NASA Astrophysics Data System (ADS)

Khomentovsky, V. V.

2008-12-01

In Russia, the terminal Neoproterozoic formally includes the Vendian of western part of the East European platform and the concurrent Yudoma Group of Siberia. As is shown in this work, the designated subdivisions correspond in the stratotypes only to the upper, Yudomian Series of the Vendian. In the Siberian platform, the Ust-Yudoma and Aim horizons of the Yudomian are tightly interrelated. The lower of them, bearing remains of Ediacaran Fauna, represents the Ediacarian Stage, whereas the upper one containing small-shelled fossils (SSF) corresponds to the Nemakit-Daldynian Stage divided into the trisulcatus and antiqua superregional zones. In more complete sections of the platform periphery, sediments of these subdivisions conformably rest on siliciclastic succession that should be ranked as basal subdivision of the Yudomian. The succession is concurrent to the Laplandian Stage of the East European platform. According to geochronological dates obtained recently, the Yudomian Series spans interval of 600-540 Ma. In the East European platform, the Upper Vendian (Yudomian) begins with the Laplandian basal tillites of synonymous stage. In the west of the platform, tillites are dated at 600 Ma like the Upper Vendian base in Siberia. The next Ediacarian Stage of the East European platform is stratigraphic equivalent of the Redkino Horizon, while summary range of the Kotlin and Rovno horizons is concurrent to that of the Nemakit-Daldynian Stage. The Vendian of Russia is conformably overlain by the Tommotian Stage of the Lower Cambrian. Intense pre-Vendian events constrained distribution areas of the Lower Vendian sediments in Russia. The Lower Vendian deposits of the East European platform are most representative and well studied in the central Urals, where they are attributed to the Serebryanka Group. In Siberia, separate subdivisions representing the Lower Vendian are the Maastakh Formation of the Olenek Uplift, two lower members of the Ushakovka Formation in the Baikal region, and the Taseeva Group of the Yenisei Range. Chronological interval of the Lower Vendian corresponds to 650-600 Ma. The Marinoan Glaciation dated in Australia at 650-635 Ma is concurrent to basal part of the pre-Yudomian interval of the Vendian in Russia, whereas the Laplandian Tillite and Gaskiers Glaciation (600-580 Ma) correspond to onset of the Yudomian Epoch. The new Ediacaran System (Knoll et al., 2004) legalized in the International Neoproterozoic scale is close in range to the entire Vendian (635-544 Ma), although without basal beds (Marinoan Tillite) it deprives the terminal Neoproterozoic of its original sense. Inferiority of the system consists also in its indivisibility into stages. Hence, it is clear that the Vendian System subdivided in detail in Russia should be retained in the rank of terminal system of the Precambrian, one of the basic in general scale of the Neoproterozoic.

Transition from strike-slip faulting to oblique subduction: active tectonics at the Puysegur Margin, South New Zealand

NASA Astrophysics Data System (ADS)

Lamarche, Geoffroy; Lebrun, Jean-Frédéric

2000-01-01

South of New Zealand the Pacific-Australia (PAC-AUS) plate boundary runs along the intracontinental Alpine Fault, the Puysegur subduction front and the intraoceanic Puysegur Fault. The Puysegur Fault is located along Puysegur Ridge, which terminates at ca. 47°S against the continental Puysegur Bank in a complex zone of deformation called the Snares Zone. At Puysegur Trench, the Australian Plate subducts beneath Puysegur Bank and the Fiordland Massif. East of Fiordland and Puysegur Bank, the Moonlight Fault System (MFS) represents the Eocene strike-slip plate boundary. Interpretation of seafloor morphology and seismic reflection profiles acquired over Puysegur Bank and the Snares Zone allows study of the transition from intraoceanic strike-slip faulting along the Puysegur Ridge to oblique subduction at the Puysegur Trench and to better understand the genetic link between the Puysegur Fault and the MFS. Seafloor morphology is interpreted from a bathymetric dataset compiled from swath bathymetry data acquired during the 1993 Geodynz survey, and single beam echo soundings acquired by the NZ Royal Navy. The Snares Zone is the key transition zone from strike-slip faulting to subduction. It divides into three sectors, namely East, NW and SW sectors. A conspicuous 3600 m-deep trough (the Snares Trough) separates the NW and East sectors. The East sector is characterised by the NE termination of Puysegur Ridge into right-stepping en echelon ridges that accommodate a change of strike from the Puysegur Fault to the MFS. Between 48°S and 47°S, in the NW sector and the Snares Trough, a series of transpressional faults splay northwards from the Puysegur Fault. Between 49°50'S and 48°S, thrusts develop progressively at Puysegur Trench into a decollement. North of 48°S the Snares Trough develops between two splays of the Puysegur Fault, indicating superficial extension associated with the subsidence of Puysegur Ridge. Seismic reflection profiles and bathymetric maps show a series of transpressional faults that splay northwards across the Snares Fault, and terminate at the top of the Puysegur trench slope. Between ca. 48°S and 46°30'S, the relative plate motion appears to be distributed over the Puysegur subduction zone and the strike-slip faults located on the edge of the upper plate. Conversely, north of ca. 46°S, a lack of active strike-slip faulting along the MFS and across most of Puysegur Bank indicates that the subduction in the northern part of Puysegur Trench accounts for most of the oblique convergence. Hence, active transpression in the Snares fault zone indicates that the relative PAC-AUS plate motion is transferred from strike-slip faulting along the Puysegur Fault to subduction at Puysegur Trench. The progressive transition from thrusts at Puysegur Trench and strike-slip faulting at the Puysegur Fault to oblique subduction at Puysegur Trench suggests that the subduction interface progressively developed from a western shallow splay of the Puysegur Fault. It implies that the transfer fault links the subduction interface at depth. A tectonic sliver is identified between Puysegur Trench and the Puysegur Fault. Its northwards motion relative to the Pacific Plate implies that is might collide with Puysegur Bank.

Geohydrology and evaluation of water-resource potential of the upper Floridan Aquifer in the Albany area, southwestern Georgia

USGS Publications Warehouse

Torak, L.J.; Davis, G.S.; Strain, G.A.; Herndon, J.G.

1993-01-01

In the Albany area of southwestern Georgia, the Upper Floridan aquifer lies entirely within the Dougherty Plain district of the Coastal Plain physiographic province, and consists of the Ocala Limestone of late Eocene age. The aquifer is divided throughout most of the study area into an upper and a lower lithologic unit, which creates an upper and a lower water-bearing zone. The lower waterbearing zone consists of alternating layers of sandy limestone and medium-brown, recrystallized dolomitic limestone, and ranges in thickness from about 50 ft to 100 ft. It is highly fractured and exhibits well-developed permeability by solution features that are responsible for transmitting most of the ground water in the aquifer. Transmissivity of the lower water-bearing zone ranges from about 90,000 to 178,000 ft2/d. The upper water-bearing zone is a finely crystallized-to-oolitic, locally dolomitic limestone having an average thickness of about 60 ft. Transmissivities are considerably less in the upper water-bearing zone than in the lower water-bearing zone. The Upper Floridan aquifer is overlain by about 20-120 ft of undifferentiated overburden consisting of fine-to-coarse quartz sand and noncalcareous clay. A clay zone about 10-30 ft thick may be continuous throughout the southwestern part of the Albany area and, where present, causes confinement of the Upper Floridan aquifer and creates perched ground water after periods of heavy rainfall. The Upper Floridan aquifer is confined below by the Lisbon Formation, a mostly dolomitic limestone that contains trace amounts of glauconite. The Lisbon Formation is at least 50 ft thick in the study area and acts as an impermeable base to the Upper Floridan aquifer. The quality of ground water in the Upper Floridan aquifer is suitable for most uses; wells generally yield water of the hard, calcium-bicarbonate type that meets the U.S. Environmental Protection Agency's Primary or Secondary Drinking-Water Regulations. The water-resource potential of the Upper Floridan aquifer was evaluated by compiling results of drilling and aquifer testing in the study area, and by conducting computer simulations of the ground-water flow system under the seasonally low conditions of November 1985, and under conditions of pumping within a 12-mi 2 area located southwest of Albany. Results of test drilling, aquifer testing, and water-quality analyses indicate that, in the area southwest of Albany, geohydrologic conditions in the Upper Floridan aquifer, undifferentiated overburden, and Lisbon Formation were favorable for the aquifer to provide a large quantity of water without having adverse effects on the groundwater system. The confinement of the Upper Floridan aquifer by the undifferentiated overburden and the rural setting of the area of potential development decrease the likelihood that chemical constituents will enter the aquifer during development of the ground-water resources. Computer simulations of ground-water flow in the Upper Floridan aquifer, incorporating conditions for regional flow across model boundaries, leakage from rivers and other surface-water features, and vertical leakage from the undifferentiated overburden, were conducted by using a finite-element model for ground-water flow in two dimensions. Comparison of computed and measured water levels in the Upper Floridan aquifer for November 1985 at 74 locations indicated that computed water levels generally were within 5 ft of the measured values, which is the accuracy to which measured water levels were known. Water-level altitudes ranged from about 260 ft to 130 ft above sea level in the study area during calibration. Aquifer discharge to the Flint River downstream from the Lake Worth dam was computed by the calibrated model to be about 1 billion gallons per day; about 300 million gallons per day (Mgal/d) greater than was measured for similar lowflow conditions. The excess computed discharge was attributed partially to stream withdrawals for

49 CFR 372.235 - New York, NY.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false New York, NY. 372.235 Section 372.235... ZONES, AND TERMINAL AREAS Commercial Zones § 372.235 New York, NY. The zone adjacent to, and commercially a part of, New York, NY, within which transportation by motor vehicle, in interstate or foreign...

76 FR 70704 - Foreign-Trade Zone 87-Lake Charles, LA; Application for Reorganization/Expansion

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... Charles, LA; Application for Reorganization/Expansion An application has been submitted to the Foreign-Trade Zones Board (the Board) by the Lake Charles Harbor & Terminal District, grantee of FTZ 87, requesting authority to reorganize and expand the zone in Lake Charles. The application was submitted...

Meiofauna as descriptor of tourism-induced changes at sandy beaches.

PubMed

Gheskiere, Tom; Vincx, Magda; Weslawski, Jan Marcin; Scapini, Felicita; Degraer, Steven

2005-08-01

Tourism has long been considered as a 'clean industry' with almost no negative effects on the environment. This study demonstrated, in two different coastal systems (Mediterranean and Baltic), that tourism related activities are particularly affecting the sandy beach meio- and nematofauna in the upper beach zone, the specific ecotone in which many meiofauna species from both the marine and the terrestrial environment congregate. Tourist upper beaches are characterized by a lower % total organic matter (%TOM), lower densities, lower diversities (absence of Insecta, Harpacticoida, Oligochaeta, terrestrial nematodes and marine Ironidae nematodes) and higher community stress compared to nearby non-tourist locations. The %TOM was found to be the single most important factor for the observed differences in meiofauna assemblage structure at tourist versus non-tourist beaches in both the Mediterranean and the Baltic region. The free-living nematode assemblages from tourist upper zones depart significantly from expectations based on random selections from the regional nematode species pool. Furthermore upper zone assemblages are characterised by a low species diversity consisting of taxonomically closely related nematode species with r-strategist features. Generally, faunal differences between tourist and non-tourist beaches are decreasing towards the lower beach zones.

78 FR 53426 - Expansion of Foreign-Trade Zone 84; Houston, Texas

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-29

..., and further subject to sunset provisions that would terminate authority on August 31, 2018, for Sites... Commerce for Import Administration, Alternate Chairman, Foreign-Trade Zones Board. ATTEST: Andrew McGilvray...

Zone separator for multiple zone vessels

DOEpatents

Jones, John B.

1983-02-01

A solids-gas contact vessel, having two vertically disposed distinct reaction zones, includes a dynamic seal passing solids from an upper to a lower zone and maintaining a gas seal against the transfer of the separate treating gases from one zone to the other, and including a stream of sealing fluid at the seal.

The Lindi Formation (upper Albian-Coniacian) and Tanzania Drilling Project Sites 36-40 (Lower Cretaceous to Paleogene): Lithostratigraphy, biostratigraphy and chemostratigraphy

NASA Astrophysics Data System (ADS)

Jiménez Berrocoso, Álvaro; Huber, Brian T.; MacLeod, Kenneth G.; Petrizzo, Maria Rose; Lees, Jacqueline A.; Wendler, Ines; Coxall, Helen; Mweneinda, Amina K.; Falzoni, Francesca; Birch, Heather; Haynes, Shannon J.; Bown, Paul R.; Robinson, Stuart A.; Singano, Joyce M.

2015-01-01

The 2009 Tanzania Drilling Project (TDP) expedition to southeastern Tanzania cored a total of 572.3 m of sediments at six new mid-Cretaceous to mid-Paleocene boreholes (TDP Sites 36, 37, 38, 39, 40A, 40B). Added to the sites drilled in 2007 and 2008, the new boreholes confirm the common excellent preservation of planktonic and benthic foraminifera and calcareous nannofossils from core samples that will be used for biostratigraphy, evolutionary studies, paleoceanography and climatic reconstructions from the Tanzanian margin, with implications elsewhere. The new sites verify the presence of a relatively expanded Upper Cretaceous succession in the region that has allowed a new stratigraphic unit, named here as the Lindi Formation (Fm), to be formally defined. The Lindi Fm (upper Albian to Coniacian), extending ∼120 km between Kilwa and Lindi, comprises a 335-m-thick, outer-shelf to upper-slope unit, consisting of dark gray claystone and siltstone interbeds, common finely-laminated intervals, minor cm-thick sandstones and up to 2.6% organic carbon in the Turonian. A subsurface, composite stratotype section is proposed for the Lindi Fm, with a gradational top boundary with the overlying Nangurukuru Fm (Santonian to Maastrichtian) and a sharp bottom contact with underlying upper Albian sandstones. The section cored at TDP Sites 36 and 38 belongs to the Lindi Fm and are of lower to middle Turonian age (planktonic foraminifera Whiteinella archaeocretacea to Helvetoglobotruncana helvetica Zones and nannofossils subzones UC6b ± UC7). The lower portion of TDP Site 39 (uppermost part of the Lindi Fm) is assigned to the lower to upper Coniacian (planktonic foraminifera Dicarinella concavata Zone and nannofossils zone UC 10), while the remaining part of this site is attributed to the Coniacian-Santonian transition and younger Santonian (planktonic foraminifera D. asymetrica Zone and upper part of nannofossils zone UC10). TDP Site 37 recovered relatively expanded (150 m thick), monotonous calcareous claystones from the lower to upper Maastrichtian (planktonic foraminifera Pseudoguembelina palpebra to Abathomphalus mayaroensis Zones and nannofossils zones UC19 to UC20aTP) that were separated by a hiatus and/or a faulted contact from overlying brecciated carbonates of the Selandian (middle Paleocene: PF Zone P3 and nannofossil zone NP5). The lower portion of TDP Sites 40A and 40B recovered sandstones and conglomerates barren of microfossils. Their overlying parts were assigned to incomplete sections of the nannofossil zones NC6A to NC8 (uppermost Barremian to lower Albian). Benthic foraminiferal assemblages allowed the Barremian to lower Aptian to be identified in TDP Sites 40A and 40B, while the upper Aptian to middle Albian (Hedbergella trocoidea to Ticinella primula Zones) were assigned using planktonic foraminifera. Cores recovered at TDP 39 (Coniacian-Santonian) and at TDP Sites 40A and 40B (Barremian-middle Albian) represent the first time that these two intervals have been continuously cored and publicly documented in Tanzania. Bulk sediment isotope records generated for the new sites show lower δ18Ocarb values in the Turonian and Santonian (∼-3.5‰ to -5‰) than in the Maastrichtian (∼-3‰), a situation consistent with extreme global warmth in the older intervals and cooling toward the end of the Cretaceous. Also, similar to Turonian sites from previous TDP expeditions, a negative δ13Corg excursion was detected across the W. archaeocretacea-H. helvetica boundary of TDP Site 36 (close to, but above, the Cenomanian-Turonian boundary). This excursion probably responded to local processes in the region, but it is unknown whether they were related to the recovery phase from Ocean Anoxic Event 2.

Upper Tithonian ammonites (Himalayitidae Spath, 1925 and Neocomitidae Salfeld, 1921) from Charens (Drôme, France)

NASA Astrophysics Data System (ADS)

Frau, Camille; Bulot, Luc G.; Wimbledon, William A. P.; Ifrim, Christina

2016-12-01

This contribution focuses on the Perisphinctoidea ammonite taxa from the Upper Tithonian at Charens (Drôme, south-east France). Emphasis is laid on five genera that belong to the families Himalayitidae and Neocomitidae. We document the precise vertical range of the index-species Micracanthoceras microcanthum, and a comparative ontogenetic- biometric analysis sheds new light on its range of variation and dimorphism as compared to the bestknown Spanish populations. As herein understood, the lower boundary of the M. microcanthum Zone (base of the Upper Tithonian) is fixed at the FAD of its index species. The faunal assemblages and species distribution of the P. andreaei Zone are rather similar to those described at the key-section of Le Chouet as confirmed by the co-occurrence of the genera Protacanthodiscus, Boughdiriella and Pratumidiscus. New palaeontological evidence supports the view that the basal Neocomitidae Busnardoiceras busnardoi was derived from Protacanthodiscus andreaei in the upper part of the P. andreaei Zone.

Cold seeps and splay faults on Nankai margin

NASA Astrophysics Data System (ADS)

Henry, P.; Ashi, J.; Tsunogai, U.; Toki, T.; Kuramoto, S.; Kinoshita, M.; Lallemant, S. J.

2003-04-01

Cold seeps (bacterial mats, specific fauna, authigenic carbonates) are common on the Nankai margin and considered as evidence for seepage of methane bearing fluids. Camera and submersible surveys performed over the years have shown that cold seeps are generally associated with active faults. One question is whether part of the fluids expelled originate from the seismogenic zone and migrate along splay faults to the seafloor. The localisation of most cold seeps on the hanging wall of major thrusts may, however, be interpreted in various ways: (a) footwall compaction and diffuse flow (b) fluid channelling along the fault zone at depths and diffuse flow near the seafloor (c) erosion and channelling along permeable strata. In 2002, new observations and sampling were performed with submersible and ROV (1) on major thrusts along the boundary between the Kumano forearc basin domain and the accretionary wedge domain, (2) on a fault affecting the forearc (Kodaiba fault), (3) on mud volcanoes in the Kumano basin. In area (1) tsunami and seismic inversions indicate that the targeted thrusts are in the slip zone of the To-Nankai 1944 earthquakes. In this area, the largest seep zone, continuous over at least 2 km, coincides with the termination of a thrust trace, indicating local fluid channelling along the edge of the fault zone. Kodaiba fault is part of another splay fault system, which has both thrusting and strike-slip components and terminates westward into an en-echelon fold system. Strong seepage activity with abundant carbonates was found on a fold at the fault termination. One mud volcano, rooted in one of the en-echelon fold, has exceptionally high seepage activity compared with the others and thick carbonate crusts. These observations suggest that fluid expulsion along fault zones is most active at fault terminations and may be enhanced during fault initiation. Preliminary geochemical results indicate signatures differ between seep sites and suggests that the two fault systems tap in different sources.

Three-dimensional velocity structure of crust and upper mantle in southwestern China and its tectonic implications

USGS Publications Warehouse

Wang, Chun-Yong; Chan, W.W.; Mooney, W.D.

2003-01-01

Using P and S arrival times from 4625 local and regional earthquakes recorded at 174 seismic stations and associated geophysical investigations, this paper presents a three-dimensional crustal and upper mantle velocity structure of southwestern China (21??-34??N, 97??-105??E). Southwestern China lies in the transition zone between the uplifted Tibetan plateau to the west and the Yangtze continental platform to the east. In the upper crust a positive velocity anomaly exists in the Sichuan Basin, whereas a large-scale negative velocity anomaly exists in the western Sichuan Plateau, consistent with the upper crustal structure under the southern Tibetan plateau. The boundary between these two anomaly zones is the Longmen Shan Fault. The negative velocity anomalies at 50-km depth in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with temperature and composition variations in the upper mantle. The Red River Fault is the boundary between the positive and negative velocity anomalies at 50-km depth. The overall features of the crustal and the upper mantle structures in southwestern China are a low average velocity, large crustal thickness variations, the existence of a high-conductivity layer in the crust or/and upper mantle, and a high heat flow value. All these features are closely related to the collision between the Indian and the Asian plates.

Quantifying Morphological Parameters of the Terminal Branching Units in a Mouse Lung by Phase Contrast Synchrotron Radiation Computed Tomography

PubMed Central

Hwang, Jeongeun; Kim, Miju; Kim, Seunghwan; Lee, Jinwon

2013-01-01

An effective technique of phase contrast synchrotron radiation computed tomography was established for the quantitative analysis of the microstructures in the respiratory zone of a mouse lung. Heitzman’s method was adopted for the whole-lung sample preparation, and Canny’s edge detector was used for locating the air-tissue boundaries. This technique revealed detailed morphology of the respiratory zone components, including terminal bronchioles and alveolar sacs, with sufficiently high resolution of 1.74 µm isotropic voxel size. The technique enabled visual inspection of the respiratory zone components and comprehension of their relative positions in three dimensions. To check the method’s feasibility for quantitative imaging, morphological parameters such as diameter, surface area and volume were measured and analyzed for sixteen randomly selected terminal branching units, each consisting of a terminal bronchiole and a pair of succeeding alveolar sacs. The four types of asymmetry ratios concerning alveolar sac mouth diameter, alveolar sac surface area, and alveolar sac volume are measured. This is the first ever finding of the asymmetry ratio for the terminal bronchioles and alveolar sacs, and it is noteworthy that an appreciable degree of branching asymmetry was observed among the alveolar sacs at the terminal end of the airway tree, despite the number of samples was small yet. The series of efficient techniques developed and confirmed in this study, from sample preparation to quantification, is expected to contribute to a wider and exacter application of phase contrast synchrotron radiation computed tomography to a variety of studies. PMID:23704918

Characterization and depositional and evolutionary history of the Apollo 17 deep drill core

NASA Technical Reports Server (NTRS)

Morris, R. V.; Lauer, H. V., Jr.; Gose, W. A.

1979-01-01

With a depth resolution of about 0.5 cm, the stratigraphy of the approximately 3 m Apollo 17 deep drill core by measurement of the total FeO concentration is characterized along with the FMR surface exposure (maturity) index Is/FeO, the metallic iron concentration Fe-vsm, and the FMR linewidth delta-H. For stratigraphic characterization, the first two parameters are the most important. Most of the core is characterized by a FeO concentration of approximately 15.5 wt. %; there is a more mafic zone in the upper approximately 75 cm where the maximum FeO concentration is approximately 18.5 wt. %, and a more felsic zone between approximately 225 and 260 cm where the minimum FeO concentration is approximately 14.0%. As indicated by Is/FeO, most of the soil in the core is submature to mature; the only immature zone is located between approximately 20 and 60 cm and is one of the most distinctive features in the core. A two stage model for the depositional and evolutionary history of the Apollo 17 deep drill core is proposed: (1) deposition by one event approximately 110 m.y. ago or deposition by a sequence of closely spaced events initating a maximum of approximately 200 m.y. ago and terminating approximately 110 m.y. ago, (2) in situ reworking (gardening) to a depth of approximately 26 cm in the period between approximately 110 m.y. ago and the present day.

The ambient acoustic environment in Laguna San Ignacio, Baja California Sur, Mexico.

PubMed

Seger, Kerri D; Thode, Aaron M; Swartz, Steven L; Urbán, Jorge R

2015-11-01

Each winter gray whales (Eschrichtius robustus) breed and calve in Laguna San Ignacio, Mexico, where a robust, yet regulated, whale-watching industry exists. Baseline acoustic environments in LSI's three zones were monitored between 2008 and 2013, in anticipation of a new road being paved that will potentially increase tourist activity to this relatively isolated location. These zones differ in levels of both gray whale usage and tourist activity. Ambient sound level distributions were computed in terms of percentiles of power spectral densities. While these distributions are consistent across years within each zone, inter-zone differences are substantial. The acoustic environment in the upper zone is dominated by snapping shrimp that display a crepuscular cycle. Snapping shrimp also affect the middle zone, but tourist boat transits contribute to noise distributions during daylight hours. The lower zone has three source contributors to its acoustic environment: snapping shrimp, boats, and croaker fish. As suggested from earlier studies, a 300 Hz noise minimum exists in both the middle and lower zones of the lagoon, but not in the upper zone.

Altitude effects on technology and productivity of small bovine farms (milk meat) in Veracruz (Gulf of Mexico).

PubMed

Ruíz-Guevara, C; De León-González, F; Soriano-Robles, R; Pérez-Carrera, A L; García-Hernández, L A

2018-03-01

The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15-22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.

Microbial abundance in the deep subsurface of the Chesapeake Bay impact crater: Relationship to lithology and impact processes

USGS Publications Warehouse

Cockell, Charles S.; Gronstal, Aaron L.; Voytek, Mary A.; Kirshtein, Julie D.; Finster, Kai; Sanford, Ward E.; Glamoclija, Mihaela; Gohn, Gregroy S.; Powars, David S.; Horton, J. Wright

2009-01-01

Asteroid and comet impact events are known to cause profound disruption to surface ecosystems. The aseptic collection of samples throughout a 1.76-km-deep set of cores recovered from the deep subsurface of the Chesapeake Bay impact structure has allowed the study of the subsurface biosphere in a region disrupted by an impactor. Microbiological enumerations suggest the presence of three major microbiological zones. The upper zone (127–867 m) is characterized by a logarithmic decline in microbial abundance from the surface through the postimpact section of Miocene to Upper Eocene marine sediments and across the transition into the upper layers of the impact tsunami resurge sediments and sediment megablocks. In the middle zone (867–1397 m) microbial abundances are below detection. This zone is predominantly quartz sand, primarily composed of boulders and blocks, and it may have been mostly sterilized by the thermal pulse delivered during impact. No samples were collected from the large granite block (1096–1371 m). The lowest zone (below 1397 m) of increasing microbial abundance coincides with a region of heavily impact-fractured, hydraulically conductive suevite and fractured schist. These zones correspond to lithologies influenced by impact processes. Our results yield insights into the influence of impacts on the deep subsurface biosphere.

Sequence-Stratigraphic Analysis of the Regional Observation Monitoring Program (ROMP) 29A Test Corehole and Its Relation to Carbonate Porosity and Regional Transmissivity in the Floridan Aquifer System, Highlands County, Florida

USGS Publications Warehouse

Ward, W. C.; Cunningham, K.J.; Renken, R.A.; Wacker, M.A.; Carlson, J.I.

2003-01-01

An analysis was made to describe and interpret the lithology of a part of the Upper Floridan aquifer penetrated by the Regional Observation Monitoring Program (ROMP) 29A test corehole in Highlands County, Florida. This information was integrated into a one-dimensional hydrostratigraphic model that delineates candidate flow zones and confining units in the context of sequence stratigraphy. Results from this test corehole will serve as a starting point to build a robust three-dimensional sequence-stratigraphic framework of the Floridan aquifer system. The ROMP 29A test corehole penetrated the Avon Park Formation, Ocala Limestone, Suwannee Limestone, and Hawthorn Group of middle Eocene to Pliocene age. The part of the Avon Park Formation penetrated in the ROMP 29A test corehole contains two composite depositional sequences. A transgressive systems tract and a highstand systems tract were interpreted for the upper composite sequence; however, only a highstand systems tract was interpreted for the lower composite sequence of the deeper Avon Park stratigraphic section. The composite depositional sequences are composed of at least five high-frequency depositional sequences. These sequences contain high-frequency cycle sets that are an amalgamation of vertically stacked high-frequency cycles. Three types of high-frequency cycles have been identified in the Avon Park Formation: peritidal, shallow subtidal, and deeper subtidal high-frequency cycles. The vertical distribution of carbonate-rock diffuse flow zones within the Avon Park Formation is heterogeneous. Porous vuggy intervals are less than 10 feet, and most are much thinner. The volumetric arrangement of the diffuse flow zones shows that most occur in the highstand systems tract of the lower composite sequence of the Avon Park Formation as compared to the upper composite sequence, which contains both a backstepping transgressive systems tract and a prograding highstand systems tract. Although the porous and permeable layers are not thick, some intervals may exhibit lateral continuity because of their deposition on a broad low-relief ramp. A thick interval of thin vuggy zones and open faults forms thin conduit flow zones mixed with relatively thicker carbonate-rock diffuse flow zones between a depth of 1,070 and 1,244 feet below land surface (bottom of the test corehole). This interval is the most transmissive part of the Avon Park Formation penetrated in the ROMP 29A test corehole and is included in the highstand systems tract of the lower composite sequence. The Ocala Limestone is considered to be a semiconfining unit and contains three depositional sequences penetrated by the ROMP 29A test corehole. Deposited within deeper subtidal depositional cycles, no zones of enhanced porosity and permeability are expected in the Ocala Limestone. A thin erosional remnant of the shallow marine Suwannee Limestone overlies the Ocala Limestone, and permeability seems to be comparatively low because moldic porosity is poorly connected. Rocks that comprise the lower Hawthorn Group, Suwannee Limestone, and Ocala Limestone form a permeable upper zone of the Upper Floridan aquifer, and rocks of the lower Ocala Limestone and Avon Park Formation form a permeable lower zone of the Upper Floridan aquifer. On the basis of a preliminary analysis of transmissivity estimates for wells located north of Lake Okeechobee, spatial relations among groups of relatively high and low transmissivity values within the upper zone are evident. Upper zone transmissivity is generally less than 10,000 feet squared per day in areas located south of a line that extends through Charlotte, Sarasota, DeSoto, Highlands, Polk, Osceola, Okeechobee, and St. Lucie Counties. Transmissivity patterns within the lower zone of the Avon Park Formation cannot be regionally assessed because insufficient data over a wide areal extent have not been compiled.

78 FR 14963 - Foreign-Trade Subzone 38A; Termination of Review of Application for Expansion; BMW Manufacturing...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-08

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 43-2011] Foreign-Trade Subzone 38A; Termination of Review of Application for Expansion; BMW Manufacturing Co., LLC (Motor Vehicles); Greer, South Carolina Notice is hereby given of termination of review of an application submitted by the South Carolina State Ports Authority, grantee of FTZ...

A Bayesian method to quantify azimuthal anisotropy model uncertainties: application to global azimuthal anisotropy in the upper mantle and transition zone

NASA Astrophysics Data System (ADS)

Yuan, K.; Beghein, C.

2018-04-01

Seismic anisotropy is a powerful tool to constrain mantle deformation, but its existence in the deep upper mantle and topmost lower mantle is still uncertain. Recent results from higher mode Rayleigh waves have, however, revealed the presence of 1 per cent azimuthal anisotropy between 300 and 800 km depth, and changes in azimuthal anisotropy across the mantle transition zone boundaries. This has important consequences for our understanding of mantle convection patterns and deformation of deep mantle material. Here, we propose a Bayesian method to model depth variations in azimuthal anisotropy and to obtain quantitative uncertainties on the fast seismic direction and anisotropy amplitude from phase velocity dispersion maps. We applied this new method to existing global fundamental and higher mode Rayleigh wave phase velocity maps to assess the likelihood of azimuthal anisotropy in the deep upper mantle and to determine whether previously detected changes in anisotropy at the transition zone boundaries are robustly constrained by those data. Our results confirm that deep upper-mantle azimuthal anisotropy is favoured and well constrained by the higher mode data employed. The fast seismic directions are in agreement with our previously published model. The data favour a model characterized, on average, by changes in azimuthal anisotropy at the top and bottom of the transition zone. However, this change in fast axes is not a global feature as there are regions of the model where the azimuthal anisotropy direction is unlikely to change across depths in the deep upper mantle. We were, however, unable to detect any clear pattern or connection with surface tectonics. Future studies will be needed to further improve the lateral resolution of this type of model at transition zone depths.

Higher species richness of octocorals in the upper mesophotic zone in Eilat (Gulf of Aqaba) compared to shallower reef zones

NASA Astrophysics Data System (ADS)

Shoham, Erez; Benayahu, Yehuda

2017-03-01

Mesophotic coral-reef ecosystems (MCEs), which comprise the light-dependent communities of corals and other organisms found at depths between 30 and 150 m, have received very little study to date. However, current technological advances, such as remotely operated vehicles and closed-circuit rebreather diving, now enable their thorough investigation. Following the reef-building stony corals, octocorals are the second most common benthic component on many shallow reefs and a major component on deep reefs, the Red Sea included. This study is the first to examine octocoral community features on upper MCEs based on species-level identification and to compare them with the shallower reef zones. The study was carried out at Eilat (Gulf of Aqaba, northern Red Sea), comparing octocoral communities at two mesophotic reefs (30-45 m) and two shallow reef zones (reef flat and upper fore-reef) by belt transects. A total of 30 octocoral species were identified, with higher species richness on the upper MCEs compared to the shallower reefs. Although the MCEs were found to host a higher number of species than the shallower reefs, both featured a similar diversity. Each reef zone revealed a unique octocoral species composition and distinct community structure, with only 16% of the species shared by both the MCEs and the shallower reefs. This study has revealed an almost exclusive dominance of zooxanthellate species at the studied upper MCE reefs, thus indicating an adequate light regime for photosynthesis there. The findings should encourage similar studies on other reefs, aimed at understanding the spatiotemporal features and ecological role of octocorals in reef ecosystems down to the deepest limit of the MCEs.

76 FR 67379 - Importation of Dracaena Plants From Costa Rica

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-01

... rooting zone for plants produced by air layering) to the farthest terminal growing point. Paragraph (y)(2... the soil line (or top of the rooting zone for plants produced by air layering) to the farthest...

Geology of Paleozoic Rocks in the Upper Colorado River Basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, Excluding the San Juan Basin

USGS Publications Warehouse

Geldon, Arthur L.

2003-01-01

The geology of the Paleozoic rocks in the Upper Colorado River Basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, was studied as part of the U.S. Geological Survey's Regional Aquifer-System Analysis Program to provide support for hydrogeological interpretations. The study area is segmented by numerous uplifts and basins caused by folding and faulting that have recurred repeatedly from Precambrian to Cenozoic time. Paleozoic rocks in the study area are 0-18,000 feet thick. They are underlain by Precambrian igneous, metamorphic, and sedimentary rocks and are overlain in most of the area by Triassic formations composed mostly of shale. The overlying Mesozoic and Tertiary rocks are 0-27,000 feet thick. All Paleozoic systems except the Silurian are represented in the region. The Paleozoic rocks are divisible into 11 hydrogeologic units. The basal hydrogeologic unit consisting of Paleozoic rocks, the Flathead aquifer, predominantly is composed of Lower to Upper Cambrian sandstone and quartzite. The aquifer is 0-800 feet thick and is overlain gradationally to unconformably by formations of Cambrian to Mississippian age. The Gros Ventre confining unit consists of Middle to Upper Cambrian shale with subordinate carbonate rocks and sandstone. The confining unit is 0-1,100 feet thick and is overlain gradationally to unconformably by formations of Cambrian to Mississippian age. The Bighom aquifer consists of Middle Cambrian to Upper Ordovician limestone and dolomite with subordinate shale and sandstone. The aquifer is 0-3,000 feet thick and is overlain unconformably by Devonian and Mississipplan rocks. The Elbert-Parting confining unit consists of Lower Devonian to Lower Mississippian limestone, dolomite, sandstone, quartzite, shale, and anhydrite. It is 0-700 feet thick and is overlain conformably to unconformably by Upper Devonian and Mississippian rocks. The Madison aquifer consists of two zones of distinctly different lithology. The lower (Redwall-Leadville) zone is 0-2,500 feet thick and is composed almost entirely of Upper Devonian to Upper Mississippian limestone, dolomite, and chert. The overlying (Darwin-Humbug) zone is 0-800 feet thick and consists of Upper Mississippian limestone, dolomite, sandstone, shale, gypsum, and solution breccia. The Madison aquifer is overlain conformably by Upper Mississippian and Pennsylvanian rocks. The Madison aquifer in most areas is overlain by Upper Mississippian to Middle Pennsylvanian rocks of the Four Comers confining unit. The lower part of this confining unit, the Belden-Molas subunit, consists of as much as 4,300 feet of shale with subordinate carbonate rocks, sandstone, and minor gypsum. The upper part of the confining unit, the Paradox-Eagle Valley subunit, in most places consists of as much as 9,700 feet of interbedded limestone, dolomite, shale, sandstone, gypsum, anhydrite, and halite. Locally, the evaporitic rocks are deformed into diapirs as much as 15,000 feet thick. The Four Corners confining unit is overlain gradationally to disconformably by Pennsylvanian rocks. The uppermost Paleozoic rocks comprise the Canyonlands aquifer, which is composed of three zones with distinctly different lithologies. The basal (Cutler-Maroon) zone consists of as much as 16,500 feet of Lower Pennsylvanian to Lower Permian sandstone, conglomerate, shale, limestone, dolomite, and gypsum. The middle (Weber-De Chelly) zone consists of as much as 4,000 feet of Middle Pennsylvanian to Lower Permian quartz sandstone with minor carbonate rocks and shale. The upper (Park City-State Bridge) zone consists of as much as 800 feet of Lower to Upper Permian limestone, dolomite, shale, sandstone, phosphorite, chert, and gypsum. The Canyonlands aquifer is overlain disconformably to unconformably by formations of Triassic and Jurassic age.

Auxin efflux facilitator and auxin dynamism responsible for the gravity-regulated development of peg in cucumber seedlings

NASA Astrophysics Data System (ADS)

Takahashi, Hideyuki; Watanabe, Chiaki; Fujii, Nobuharu; Miyazawa, Yutaka

Cucumber seedlings develop a protuberance, peg, by which seed coats are pulled out just af-ter germination. The peg is usually formed on the lower side of the transition zone between hypocotyl and root of the seedlings grown in a horizontal position. Our previous spaceflight experiment showed that unilateral positioning of a peg in cucumber seedlings occurred due to its suppression on the upper side of the transition zone because seedlings grown in microgravity developed a peg on each side of the transition zone. We also showed that auxin was a major factor responsible for peg development. There was a redistribution of auxin in the gravistimu-lated transition zone, decreasing IAA level on the upper side, and IAA application induced a peg on both lower and upper sides of the transition zone. In addition, peg was released from its suppression in the seedlings treated with inhibitors of auxin efflux. Namely, two pegs devel-oped in the TIBA-treated seedlings even when they were grown in a horizontal position. These results imply that a reduction of auxin level due to its efflux is required for the suppression of peg development on the upper side of the transition zone in a horizontal position. To under-stand molecular mechanism underlying the negative control of morphogenesis by graviresponse in cucumber seedlings, we isolated cDNAs of auxin efflux facilitators, CsPINs, from cucumber and examined the expressions of their proteins, in relation to the redistribution of endogenous auxin and peg development. We isolated six cDNAs of PIN homologues CsPIN1 to CsPIN6 from cucumber. By immunohistochemical study using some of their anti-bodies, we revealed that CsPIN1 was localized in endodermis, vascular tissue and pith around the transition zone of cucumber seedlings. In cucumber seedlings grown in a vertical position with radicles pointing down, CsPIN1 in endodermal cells was mainly localized on the plasma membrane neighboring vascular bundle but not on the plasma membrane next to the cortex. This CsPIN1 localization could play a role in transporting auxin from cortex to vascular bundle. In both vascular and pith tissues, CsPIN1 was localized on the bottom plasma membrane of the cells, which could allow auxin to move toward the roots. In the seedlings grown in a horizontal position, endoder-mal cells situated above the vascular bundle localized CsPIN1 on the lower plasma membrane, whereas the polarized localization of CsPIN1 in endodermal cells situated below the vascular bundle became less clear. This differential expression of CsPIN1 in the endodermis commenced within 30 min after gravistimulation. We measured endogenous IAA contents in the transi-tion zone of the 24-hour-old seedlings. In the longitudinally halved transition zone of seedlings grown in a horizontal position, free IAA content was significantly lowered in the upper side, compared to that of the lower side or either side of the transition zone in a vertical position. When 24-hour-old seedlings grown in a vertical position were gravistimulated by reorienting them to the horizontal, free IAA in the lower side of the transition zone increased by 30 min after gravistimulation and eventually decreased to the control level by 180 min after gravistim-ulation. IAA content in the upper side of the transition zone did not change much and was comparable to that in the vertical transition zone during 180 min after gravistimulation. Thus, it appears that gravistimulation causes an immediate increase of IAA level in the lower side and its eventual decrease in the upper side of the transition zone. The gravity-induced changes in CsPIN1 localization in endodermal cells could be involved in auxin redistribution that leads to unilateral positioning of a peg in cucumber seedlings.

Microstructural evidence for northeastward movement on the Chocolate Mountains fault zone, southeastern California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simpson, C.

1990-01-10

Microstructural analysis of rocks from the Chocolate Mountains fault zone, Gavilan Hills area, southeastern California, show unequivocal evidence for northeast directed transport of the upper plate gneisses over lower plate Orocopia schists. Samples were taken from transects through the fault zone. Prefaulting fabrics in upper plate gneisses show a strong component of northeast directed rotational deformation under lower amphibolite facies conditions. In contrast, prefaulting lower plate Orocopia schists show strongly coaxial fabrics (minimum stretch value of 2.2) formed at greenschist grade. Mylonitic fabrics associated with the Chocolate Mountains fault are predominantly northeast directed shear bands that are unidirectional (northeastward) inmore » the gneisses but bi-directional in the schists, suggesting a significant component of nonrotational deformation occurred in the Orocopia schists during and after emplacement of the upper plate. The kinematic findings are in agreement with Dillon et al. (1989), who found that the vergence of asymmetrical folds within the fault zone indicates overthrusting to the northeast, toward the craton, in this region. The available evidence favors a single protracted northeastward movement on the Chocolate Mountains fault zone with temperatures waning as deformation proceeded.« less

Proterozoic crustal boundary in the southern part of the Illinois Basin

USGS Publications Warehouse

Heigold, P.C.; Kolata, Dennis R.

1993-01-01

Recently acquired COCORP and proprietary seismic reflection data in the southern part of the Illinois Basin, combined with other geological and geophysical data, indicate that a WNW-trending Proterozoic terrane boundary (40 km wide) lies within basement. The boundary is characterized by the termination of subhorizontal Proterozoic reflectors and associated diffraction patterns along a line coinciding with the major magnetic lineament in this region (South Central Magnetic Lineament). North of the boundary, where reflectors thought to represent a sequence of layered Proterozoic rocks in the upper crust are widespread and as much as 11 km thick, total magnetic intensity values are relatively high, suggesting layers of rock with high magnetic susceptibility. To the south, the Proterozoic rocks are acoustically transparent on seismic reflection sections and total magnetic intensity values are relatively low. Moreover, relatively high Bouguer gravity anomaly values to the south may be caused by a dense, altered, lower crustal layer similar to that interpreted from deep seismic refraction studies to underlie the northern Mississippi Embayment. The boundary lies along the projected trend of the northern margin of the Early Proterozoic Central Plains orogen and we suggest that it marks the convergent margin of this orogen. Reactivation of the boundary and the associated zone of weakness during late Paleozoic times apparently resulted in structural deformation in the southern part of the Illinois Basin, including movement along the Cottage Grove Fault System and Ste. Genevieve Fault Zone and igneous activity at Hicks Dome. In addition to the role played by this crustal boundary in the evolution of the Illinois Basin, its location between the Wabash Valley Seismic Zone to the northeast and the New Madrid Seismic Zone to the southwest may be a significant factor in present-day seismicity. ?? 1993.

Invaginating Structures in Mammalian Synapses

PubMed Central

Petralia, Ronald S.; Wang, Ya-Xian; Mattson, Mark P.; Yao, Pamela J.

2018-01-01

Invaginating structures at chemical synapses in the mammalian nervous system exist in presynaptic axon terminals, postsynaptic spines or dendrites, and glial processes. These invaginating structures can be divided into three categories. The first category includes slender protrusions invaginating into axonal terminals, postsynaptic spines, or glial processes. Best known examples of this category are spinules extending from postsynaptic spines into presynaptic terminals in forebrain synapses. Another example of this category are protrusions from inhibitory presynaptic terminals invaginating into postsynaptic neuronal somas. Regardless of the direction and location, the invaginating structures of the first category do not have synaptic active zones within the invagination. The second category includes postsynaptic spines invaginating into presynaptic terminals, whereas the third category includes presynaptic terminals invaginating into postsynaptic spines or dendrites. Unlike the first category, the second and third categories have active zones within the invagination. An example of the second category are mossy terminal synapses of the hippocampal CA3 region, in which enlarged spine-like structures invaginate partly or entirely into mossy terminals. An example of the third category is the neuromuscular junction (NMJ) where substantial invaginations of the presynaptic terminals invaginate into the muscle fibers. In the retina, rod and cone synapses have invaginating processes from horizontal and bipolar cells. Because horizontal cells act both as post and presynaptic structures, their invaginating processes represent both the second and third category. These invaginating structures likely play broad yet specialized roles in modulating neuronal cell signaling. PMID:29674962

Cascade solar cell having conductive interconnects

DOEpatents

Borden, Peter G.; Saxena, Ram R.

1982-10-26

Direct ohmic contact between the cells in an epitaxially grown cascade solar cell is obtained by means of conductive interconnects formed through grooves etched intermittently in the upper cell. The base of the upper cell is directly connected by the conductive interconnects to the emitter of the bottom cell. The conductive interconnects preferably terminate on a ledge formed in the base of the upper cell.

New biostratigraphic data on an Upper Hauterivian–Upper Barremian ammonite assemblage from the Dolomites (Southern Alps, Italy)

PubMed Central

Lukeneder, Alexander

2012-01-01

A biostratigraphic subdivision, based on ammonites, is proposed for the Lower Cretaceous pelagic to hemipelagic succession of the Puez area (Southern Alps, Italy). Abundant ammonites enable recognition of recently established Mediterranean ammonite zones from the upper Hauterivian Balearites balearis Zone (Crioceratites krenkeli Subzone) to the upper Barremian Gerhardtia sartousiana Zone (Gerhardtia sartousiana Subzone). Ammonites are restricted to the lowermost part of the Puez Formation, the Puez Limestone Member (ca. 50 m; marly limestones; Hauterivian–Barremian). Numerous ammonite specimens are documented for the first time from the Southern Alps (e.g., Dolomites). Ammonite abundances are clearly linked to sea-level changes from Late Hauterivian to mid Late Barremian times. Abundance and diversity peaks occur during phases of high sea-level pulses and the corresponding maximum flooding surfaces (P. mortilleti/P. picteti and G. sartousiana zones). The ammonite composition of the Puez Formation sheds light on the Early Cretaceous palaeobiogeography of the Dolomites. It also highlights the palaeoenvironmental evolution of basins and plateaus and provides insights into the faunal composition and distribution within the investigated interval. The intermittent palaeogeographic situation of the Puez locality during the Early Cretaceous serves as a key for understanding Mediterranean ammonite distribution. PMID:27087716

The upper-mantle transition zone beneath the Chile-Argentina flat subduction zone

NASA Astrophysics Data System (ADS)

Bagdo, Paula; Bonatto, Luciana; Badi, Gabriela; Piromallo, Claudia

2016-04-01

The main objective of the present work is the study of the upper mantle structure of the western margin of South America (between 26°S and 36°S) within an area known as the Chile-Argentina flat subduction zone. For this purpose, we use teleseismic records from temporary broad band seismic stations that resulted from different seismic experiments carried out in South America. This area is characterized by on-going orogenic processes and complex subduction history that have profoundly affected the underlying mantle structure. The detection and characterization of the upper mantle seismic discontinuities are useful to understand subduction processes and the dynamics of mantle convection; this is due to the fact that they mark changes in mantle composition or phase changes in mantle minerals that respond differently to the disturbances caused by mantle convection. The discontinuities at a depth of 410 km and 660 km, generally associated to phase changes in olivine, vary in width and depth as a result of compositional and temperature anomalies. As a consequence, these discontinuities are an essential tool to study the thermal and compositional structure of the mantle. Here, we analyze the upper-mantle transition zone discontinuities at a depth of 410 km and 660 km as seen from Pds seismic phases beneath the Argentina-Chile flat subduction.

Glutenite bodies sequence division of the upper Es4 in northern Minfeng zone of Dongying Sag, Bohai Bay Basin, China

NASA Astrophysics Data System (ADS)

Shao, Xupeng

2017-04-01

Glutenite bodies are widely developed in northern Minfeng zone of Dongying Sag. Their litho-electric relationship is not clear. In addition, as the conventional sequence stratigraphic research method drawbacks of involving too many subjective human factors, it has limited deepening of the regional sequence stratigraphic research. The wavelet transform technique based on logging data and the time-frequency analysis technique based on seismic data have advantages of dividing sequence stratigraphy quantitatively comparing with the conventional methods. Under the basis of the conventional sequence research method, this paper used the above techniques to divide the fourth-order sequence of the upper Es4 in northern Minfeng zone of Dongying Sag. The research shows that the wavelet transform technique based on logging data and the time-frequency analysis technique based on seismic data are essentially consistent, both of which divide sequence stratigraphy quantitatively in the frequency domain; wavelet transform technique has high resolutions. It is suitable for areas with wells. The seismic time-frequency analysis technique has wide applicability, but a low resolution. Both of the techniques should be combined; the upper Es4 in northern Minfeng zone of Dongying Sag is a complete set of third-order sequence, which can be further subdivided into 5 fourth-order sequences that has the depositional characteristics of fine-upward sequence in granularity. Key words: Dongying sag, northern Minfeng zone, wavelet transform technique, time-frequency analysis technique ,the upper Es4, sequence stratigraphy

33 CFR 165.1708 - Tongass Narrows, Ketchikan, Alaska-Safety Zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

...°39′40″ W used to conduct fireworks displays. (b) Effective date. The safety zone becomes effective on July 3 each year at 10 p.m. ADT. It terminates at the conclusion of the fireworks display at... fireworks display is postponed because of inclement weather, the date and duration of the safety zone will...

Middle Triassic molluscan fossils of biostratigraphic significance from the Humboldt Range, northwestern Nevada

USGS Publications Warehouse

Silberling, Norman J.; Nichols, K.M.

1982-01-01

Cephalopods and bivalves of the genus Daonella occur at certain levels throughout the Middle Triassic section in the Humboldt Range, northwestern Nevada. These fossiliferous strata are assigned to the Fossil Hill Member and upper member of the Prida Formation, which here forms the oldest part of the Star Peak Group. The distribution and abundance of fossils within the section is uneven, partly because of original depositional patterns within the dominantly calcareous succession and partly because of diagenetic secondary dolomitization and hydrothermal metamorphism in parts of the range.Lower and middle Anisian fossil localities are restricted to the northern part of the range and are scattered, so that only three demonstrably distinct stratigraphic levels are represented. Cephalopods from these localities are characteristic of the Caurus Zone and typify the lower and upper parts of the Hyatti Zone, a new zonal unit whose faunas have affinity with those from the older parts of the Varium Zone in Canada.The upper Anisian and lowermost Ladinian, as exposed in the vicinity of Fossil Hill in the southern part of the range, are extremely fossiliferous. Cephalopod and Daonella shells form a major component of many of the limestone interbeds in the calcareous fine-grained clastic section here. Stratigraphically controlled bedrock collections representing at least 20 successive levels have been made from the Fossil Hill area, which is the type locality for the Rotelliformis, Meeki, and Occidentalis Zones of the upper Anisian and the Subasperum Zone of the lower Ladinian. Above the Subasperum Zone fossils are again scarce; upper Ladinian faunas representing the Daonella lommeli beds occur at only a few places in the upper member of the Prida Formation.Although unevenly fossiliferous, the succession of Middle Triassic cephalopod and Daonella faunas in the Humboldt Range is one of the most complete of any known in the world. Newly collected faunas from this succession provide the basis for revising the classic monograph on Middle Triassic marine invertebrates of North America published in 1914 by J. P. Smith and based largely on stratigraphically uncontrolled collections from the Humboldt Range. Taxonomic treatment of these collections, old and new, from the Humboldt Range provides the documentation necessary to establish this Middle Triassic succession as a biostratigraphic standard of reference.Of the 68 species of ammonites described or discussed, 4 are from the lower Anisian, 20 from the middle Anisian, 39 from the upper Anisian, 4 from the lower Ladinian, and 1 from the upper Ladinian. A few additional ammonite species from other localities in Nevada are also treated in order to clarify their morphologic characteristics and stratigraphic occurrence. Other elements in the Middle Triassic molluscan faunas of the Humboldt Range comprise five species of nautiloids and three of coleoids from the middle and upper Anisian parts of the section. Eight more or less stratigraphically restricted species of Daonella occur in the upper Anisian and Ladinian.

15 CFR 923.81 - Requests for amendments.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management... and appropriate, including a discussion of the following factors, as relevant; changes in coastal zone...

15 CFR 923.81 - Requests for amendments.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management... and appropriate, including a discussion of the following factors, as relevant; changes in coastal zone...

Conventional and technical diving surveys reveal elevated biomass and differing fish community composition from shallow and upper mesophotic zones of a remote United States coral reef.

PubMed

Muñoz, Roldan C; Buckel, Christine A; Whitfield, Paula E; Viehman, Shay; Clark, Randy; Taylor, J Christopher; Degan, Brian P; Hickerson, Emma L

2017-01-01

The world's coral reefs appear to be in a global decline, yet most previous research on coral reefs has taken place at depths shallower than 30 m. Mesophotic coral ecosystem (depths deeper than ~30 m) studies have revealed extensive, productive habitats and rich communities. Despite recent advances, mesophotic coral ecosystems remain understudied due to challenges with sampling at deeper depths. The few previous studies of mesophotic coral ecosystems have shown variation across locations in depth-specific species composition and assemblage shifts, potentially a response to differences in habitat or light availability/water clarity. This study utilized scuba to examine fish and benthic communities from shallow and upper mesophotic (to 45 m) zones of Flower Garden Banks National Marine Sanctuary (FGBNMS, 28°0'N; 93°50'W) from 2010-2012. Dominant planktivores were ubiquitous in shallow and upper mesophotic habitats, and comparisons with previous shallow research suggest this community distribution has persisted for over 30 years. Planktivores were abundant in shallow low-relief habitats on the periphery of the coral reef, and some of these sites that contained habitat transitioning from high to low relief supported high biomass of benthic predators. These peripheral sites at FGBNMS may be important for the trophic transfer of oceanic energy to the benthic coral reef. Distinct differences between upper mesophotic and shallow communities were also observed. These included greater overall fish (as well as apex predator) biomass in the upper mesophotic, differences in apex predator community composition between depth zones, and greater percent cover of algae, rubble, sand, and sponges in the upper mesophotic. Greater fish biomass in the upper mesophotic and similar fish community composition between depth zones provide preliminary support that upper mesophotic habitats at FGBNMS have the capacity to serve as refugia for the shallow-water reefs. Diving surveys of the upper mesophotic and shallow-water coral reef have revealed valuable information concerning the reef fish community in the northern Gulf of Mexico, with implications for the conservation of apex predators, oceanic coral reefs, and the future management of FGBNMS.

Conventional and technical diving surveys reveal elevated biomass and differing fish community composition from shallow and upper mesophotic zones of a remote United States coral reef

PubMed Central

Buckel, Christine A.; Whitfield, Paula E.; Viehman, Shay; Clark, Randy; Taylor, J. Christopher; Degan, Brian P.; Hickerson, Emma L.

2017-01-01

The world’s coral reefs appear to be in a global decline, yet most previous research on coral reefs has taken place at depths shallower than 30 m. Mesophotic coral ecosystem (depths deeper than ~30 m) studies have revealed extensive, productive habitats and rich communities. Despite recent advances, mesophotic coral ecosystems remain understudied due to challenges with sampling at deeper depths. The few previous studies of mesophotic coral ecosystems have shown variation across locations in depth-specific species composition and assemblage shifts, potentially a response to differences in habitat or light availability/water clarity. This study utilized scuba to examine fish and benthic communities from shallow and upper mesophotic (to 45 m) zones of Flower Garden Banks National Marine Sanctuary (FGBNMS, 28°0ʹN; 93°50ʹW) from 2010–2012. Dominant planktivores were ubiquitous in shallow and upper mesophotic habitats, and comparisons with previous shallow research suggest this community distribution has persisted for over 30 years. Planktivores were abundant in shallow low-relief habitats on the periphery of the coral reef, and some of these sites that contained habitat transitioning from high to low relief supported high biomass of benthic predators. These peripheral sites at FGBNMS may be important for the trophic transfer of oceanic energy to the benthic coral reef. Distinct differences between upper mesophotic and shallow communities were also observed. These included greater overall fish (as well as apex predator) biomass in the upper mesophotic, differences in apex predator community composition between depth zones, and greater percent cover of algae, rubble, sand, and sponges in the upper mesophotic. Greater fish biomass in the upper mesophotic and similar fish community composition between depth zones provide preliminary support that upper mesophotic habitats at FGBNMS have the capacity to serve as refugia for the shallow-water reefs. Diving surveys of the upper mesophotic and shallow-water coral reef have revealed valuable information concerning the reef fish community in the northern Gulf of Mexico, with implications for the conservation of apex predators, oceanic coral reefs, and the future management of FGBNMS. PMID:29161314

Evaluation of the fuselage lap joint fatigue and terminating action repair

NASA Technical Reports Server (NTRS)

Samavedam, Gopal; Thomson, Douglas; Jeong, David Y.

1994-01-01

Terminating action is a remedial repair which entails the replacement of shear head countersunk rivets with universal head rivets which have a larger shank diameter. The procedure was developed to eliminate the risk of widespread fatigue damage (WFD) in the upper rivet row of a fuselage lap joint. A test and evaluation program has been conducted by Foster-Miller, Inc. (FMI) to evaluate the terminating action repair of the upper rivet row of a commercial aircraft fuselage lap splice. Two full scale fatigue tests were conducted on fuselage panels using the growth of fatigue cracks in the lap joint. The second test was performed to evaluate the effectiveness of the terminating action repair. In both tests, cyclic pressurization loading was applied to the panels while crack propagation was recorded at all rivet locations at regular intervals to generate detailed data on conditions of fatigue crack initiation, ligament link-up, and fuselage fracture. This program demonstrated that the terminating action repair substantially increases the fatigue life of a fuselage panel structure and effectively eliminates the occurrence of cracking in the upper rivet row of the lap joint. While high cycle crack growth was recorded in the middle rivet row during the second test, failure was not imminent when the test was terminated after cycling to well beyond the service life. The program also demonstrated that the initiation, propagation, and linkup of WFD in full-scale fuselage structures can be simulated and quantitatively studied in the laboratory. This paper presents an overview of the testing program and provides a detailed discussion of the data analysis and results. Crack distribution and propagation rates and directions as well as frequency of cracking are presented for both tests. The progression of damage to linkup of adjacent cracks and to eventual overall panel failure is discussed. In addition, an assessment of the effectiveness of the terminating action repair and the occurrence of cracking in the middle rivet row is provided, and conclusions of practical interest are drawn.

Spatial Distribution of Seismic Anisotropy in the Crust in the Northeast Front Zone of Tibetan Plateau

NASA Astrophysics Data System (ADS)

Gao, Y.; Wang, Q.; SHI, Y.

2017-12-01

There are orogenic belts and strong deformation in northeastern zone of Tibetan Plateau. The media in crust and in the upper mantle are seismic anisotropic there. This study uses seismic records by permanent seismic stations and portable seismic arrays, and adopts analysis techniques on body waves to obtain spatial anisotropic distribution in northeastern front zone of Tibetan Plateau. With seismic records of small local earthquakes, we study shear-wave splitting in the upper crust. The polarization of fast shear wave (PFS) can be obtained, and PFS is considered parallel to the strike of the cracks, as well as the direction of maximum horizontal compressive stress. However, the result shows the strong influence from tectonics, such as faults. It suggests multiple-influence including stress and fault. Spatial distribution of seismic anisotropy in study zone presents the effect in short range. PFS at the station on the strike-slip fault is quite different to PFS at station just hundreds of meters away from the fault. With seismic records of teleseismic waveforms, we obtained seismic anisotropy in the whole crust by receiver functions. The PFS directions from Pms receiver functions show consistency, generally in WNW. The time-delay of slow S phases is significant. With seismic records of SKS, PKS and SKKS phases, we can detect seismic anisotropy in the upper mantle by splitting analysis. The fast directions of these phases also show consistency, generally in WNW, similar to those of receiver functions, but larger time-delays. It suggests significant seismic anisotropy in the crust and crustal deformation is coherent to that in the upper mantle.Seismic anisotropy in the upper crust, in the whole crust and in the upper mantle are discussed both in difference and tectonic implications [Grateful to the support by NSFC Project 41474032].

33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

Code of Federal Regulations, 2011 CFR

2011-07-01

... the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. (a...

33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

Code of Federal Regulations, 2014 CFR

2014-07-01

... the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. (a...

33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

Code of Federal Regulations, 2010 CFR

2010-07-01

... the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. (a...

33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

Code of Federal Regulations, 2012 CFR

2012-07-01

... the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. (a...

33 CFR 334.1050 - Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of...

Code of Federal Regulations, 2013 CFR

2013-07-01

... the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1050 Oakland Outer Harbor adjacent to the Military Ocean Terminal, Bay Area, Pier No. 8 (Port of Oakland Berth No. 10); restricted area. (a...

EHF (28/19 GHz) personal communications satellite terminal development

NASA Technical Reports Server (NTRS)

Pike, Corey

1991-01-01

The concept of communicating on a personal basis using a small terminal has been investigated globally from many different applications and technology perspectives. Applications range from terrestrial handheld communicators for paging, cellular, zone voice/data networks, etc., to satellite terminals of pocket dimensions for voice/low speed data or similar terminals using larger antennas for VSAT, news gathering (30 cm), and video (1.2 m). A brief status of some developments in the satellite personal communications at CRC will be presented.

Fracture properties from tight reservoir outcrop analogues with application to geothermal exploration

NASA Astrophysics Data System (ADS)

Philipp, Sonja L.; Reyer, Dorothea; Afsar, Filiz; Bauer, Johanna F.; Meier, Silke; Reinecker, John

2015-04-01

In geothermal reservoirs, similar to other tight reservoirs, fluid flow may be intensely affected by fracture systems, in particular those associated with fault zones. When active (slipping) the fault core, that is, the inner part of a fault zone, which commonly consists of breccia or gouge, can suddenly develop high permeability. Fault cores of inactive fault zones, however, may have low permeabilities and even act as flow barriers. In the outer part of a fault zone, the damage zone, permeability depends mainly on the fracture properties, that is, the geometry (orientation, aperture, density, connectivity, etc.) of the fault-associated fracture system. Mineral vein networks in damage zones of deeply eroded fault zones in palaeogeothermal fields demonstrate their permeability. In geothermal exploration, particularly for hydrothermal reservoirs, the orientation of fault zones in relation to the current stress field as well as their internal structure, in particular the properties of the associated fracture system, must be known as accurately as possible for wellpath planning and reservoir engineering. Here we present results of detailed field studies and numerical models of fault zones and associated fracture systems in palaeogeo¬thermal fields and host rocks for geothermal reservoirs from various stratigraphies, lithologies and tectonic settings: (1) 74 fault zones in three coastal sections of Upper Triassic and Lower Jurassic age (mudstones and limestone-marl alternations) in the Bristol Channel Basin, UK. (2) 58 fault zones in 22 outcrops from Upper Carboniferous to Upper Cretaceous in the Northwest German Basin (siliciclastic, carbonate and volcanic rocks); and (3) 16 fault zones in 9 outcrops in Lower Permian to Middle Triassic (mainly sandstone and limestone) in the Upper Rhine Graben shoulders. Whereas (1) represent palaeogeothermal fields with mineral veins, (2) and (3) are outcrop analogues of reservoir horizons from geothermal exploration. In the study areas of palaeo¬geothermal fields in the Bristol Channel (1), all mineral veins, most of which are extension fractures, are of calcite. They are clearly associated with the faults and indicate that geothermal water was transported along the then-active faults into the host rocks with evidence of injection as hydrofractures. Layers with contrasting mechanical properties (in particular, stiffnesses), however, acted as stress barriers and lead to fracture arrest. Along some faults, veins propagated through the barriers along faults to shallower levels. In the Northwest German Basin (2) there are pronounced differences between normal-fault zones in carbonate and clastic rocks. Only in carbonate rocks clear damage zones occur, characterized by increased fracture frequencies and high amounts of fractures with large apertures. On the Upper Rhine Graben shoulders (3) damage zones in Triassic Muschelkalk limestones are well developed; fault cores are narrow and comprise breccia, clay smear, host rock lenses and mineralization. A large fault zone in Triassic Bunter sandstone shows a clearly developed fault core with fault gouge, slip zones, deformation bands and host rock lenses, a transition zone with mostly disturbed layering and highest fracture frequency, and a damage zone. The latter damage zone is compared to the damage zone of a large Bunter sandstone fault zone currently explored for geothermal energy production. The numerical models focus on stress field development, fracture propagation and associated permeability changes. These studies contribute to the understanding of the hydromechanical behaviour of fault zones and related fluid transport in fractured reservoirs complementing predictions based on geophysical measurements. Eventually we aim at classifying and quantifying fracture system properties in fault zones to improve exploration and exploitation of geothermal reservoirs. Acknowledgements The authors appreciate the support of 'Niedersächsisches Ministerium für Wissen¬schaft und Kultur' and 'Baker Hughes' within the gebo research project (http://www.gebo-nds.de), the Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMU; FKZ: 0325302, AuGE) and the Deutsche Forschungsgemeinschaft. GeoEnergy GmbH, Karlsruhe, is thanked for explorational data.

Hair-cell counts and afferent innervation patterns in the cristae ampullares of the squirrel monkey with a comparison to the chinchilla

NASA Technical Reports Server (NTRS)

Fernandez, C.; Lysakowski, A.; Goldberg, J. M.

1995-01-01

1. The numbers of type I and type II hair cells were estimated by dissector techniques applied to semithin, stained sections of the horizontal, superior, and posterior cristae in the squirrel monkey and the chinchilla. 2. The crista in each species was divided into concentrically arranged central, intermediate, and peripheral zones of equal areas. The three zones can be distinguished by the sizes of individual hair cells and calyx endings, by the density of hair cells, and by the relative frequency of calyx endings innervating single or multiple type I hair cells. 3. In the monkey crista, type I hair cells outnumber type II hair cells by a ratio of almost 3:1. The ratio decreases from 4-5:1 in the central and intermediate zones to under 2:1 in the peripheral zone. For the chinchilla, the ratio is near 1:1 for the entire crista and decreases only slightly between the central and peripheral zones. 4. Nerve fibers supplying the cristae in the squirrel monkey were labeled by extracellular injections of horseradish peroxidase (HRP) into the vestibular nerve. Peripheral terminations of individual fibers were reconstructed and related to the zones of the cristae they innervated and to the sizes of their parent axons. Results were similar for the horizontal, superior, and posterior cristae. 5. Axons seldom bifurcate below the neuroepithelium. Most fibers begin branching shortly after crossing the basement membrane. Their terminal arbors are compact, usually extending no more than 50-100 microns from the parent exon. A small number of long intraepithelial fibers enter the intermediate and peripheral zones of the cristae near its base, then run unbranched for long distances through the neuroepithelium to reach the central zone. 6. There are three classes of afferent fibers innervating the monkey crista. Calyx fibers terminate exclusively on type I hair cells, and bouton fibers end only on type II hair cells. Dimorphic fibers provide a mixed innervation, including calyx endings to type I hair cells and bouton endings to type II hair cells. Long intraepithelial fibers are calyx and dimorphic units, whose terminal fields are similar to those of other fibers. The central zone is innervated by calyx and dimorphic fibers; the peripheral zone, by bouton and dimorphic fibers; and the intermediate zone, by all three kinds of fibers. Internal (axon) diameters are largest for calyx fibers and smallest for bouton fibers. Of the entire sample of 286 labeled fibers, 52% were dimorphic units, 40% were calyx units, and 8% were bouton units.(ABSTRACT TRUNCATED AT 400 WORDS).

Burnable absorber arrangement for fuel bundle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crowther, R.L.; Townsend, D.B.

1986-12-16

This patent describes a boiling water reactor core whose operation is characterized by a substantial proportion of steam voids with concomitantly reduced moderation toward the top of the core when the reactor is in its hot operating condition. The reduced moderation leads to slower burnup and greater conversion ratio in an upper core region so that when the reactor is in its cold shut down condition the resulting relatively increased moderation in the upper core region is accompanied by a reactivity profile that peaks in the upper core region. A fuel assembly is described comprising; a component of fissile materialmore » distributed over a substantial axial extent of the fuel assembly; and a component of neutron absorbing material having an axial distribution characterized by an enhancement in an axial zone of the fuel assembly, designated the cold shutdown control zone, corresponding to at least a portion of the axial region of the core when the cold shutdown reactivity peaks. The aggregate amount of neutron absorbing material in the cold shutdown zone of the fuel assembly is greater than the aggregate amount of neutron absorbing material in the axial zones of the fuel assembly immediately above and immediately below the cold shutdown control zone whereby the cold shutdown reactivity peak is reduced relative to the cold shutdown reactivity in the zones immediately above and immediately below the cold shutdown control zone. The cold shutdown zone has an axial extent measured from the bottom of the fuel assembly in the range between 68-88 percent of the height of the fissile material in the fuel assembly.« less

How many upper Eocene microspherule layers: More than we thought

NASA Technical Reports Server (NTRS)

Hazel, Joseph E.

1988-01-01

The scientific controversy over the origin of upper Eocene tektites, microtektites and other microspherules cannot be logically resolved until it is determined just how many events are involved. The microspherule-bearing beds in marine sediments have been dated using standard biozonal techniques. Although a powerful stratigraphic tool, zonal biostratigraph has its limitations. One is that if an event, such as a microspherule occurrence, is observed to occur in a zone at one locality and then a similar event observed in the same zone at another locality, it still may be unwarranted to conclude that these events exactly correlate. To be in a zone a sample only need be between the fossil events that define the zone boundaries. It is often very difficult to accurately determine where within a zone one might be. Further, the zone defining events do not everywhere occur at the same points in time. That is, the ranges of the defining taxa are not always filled. Thus, the length of time represented by a zone (but not, of course, its chronozone) can vary from place to place. These problems can be offset by use of chronostratigraphic modelling techniques such as Graphic Correlation. This technique was used to build a Cretaceous and Cenozoic model containing fossil, magnetopolarity, and other events. The scale of the model can be demonstrated to be linear with time. This model was used to determine the chronostratigraphic position of upper Eocene microspherule layers.

76 FR 80886 - Reorganization of Foreign-Trade Zone 277 Under Alternative Site Framework; Western Maricopa...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-27

... magnet sites; Whereas, notice inviting public comment was given in the Federal Register (76 FR 30906, 05...-purpose zone project, and to a five-year ASF sunset provision for magnet sites that would terminate...

Local extirpations and regional declines of endemic upper beach invertebrates in southern California

NASA Astrophysics Data System (ADS)

Hubbard, D. M.; Dugan, J. E.; Schooler, N. K.; Viola, S. M.

2014-10-01

Along the world's highly valued and populous coastlines, the upper intertidal zones of sandy beach ecosystems and the biodiversity that these zones support are increasingly threatened by impacts of human activities, coastal development, erosion, and climate change. The upper zones of beaches typically support invertebrates with restricted distributions and dispersal, making them particularly vulnerable to habitat loss and fragmentation. We hypothesized that disproportionate loss or degradation of these zones in the last century has resulted in declines of upper shore macroinvertebrates in southern California. We identified a suite of potentially vulnerable endemic upper beach invertebrates with direct development, low dispersal and late reproduction. Based on the availability of printed sources and museum specimens, we investigated historical changes in distribution and abundance of two intertidal isopod species (Tylos punctatus, Alloniscus perconvexus) in southern California. Populations of these isopods have been extirpated at numerous historically occupied sites: T. punctatus from 16 sites (57% decrease), and A. perconvexus from 14 sites (64% decrease). During the same period, we found evidence of only five colonization events. In addition, the northern range limit of the southern species, T. punctatus, moved south by 31 km (8% of range on California mainland) since 1971. Abundances of T. punctatus have declined on the mainland coast; only three recently sampled populations had abundances >7000 individuals m-1. For A. perconvexus populations, abundances >100 individuals m-1 now appear to be limited to the northern part of the study area. Our results show that numerous local extirpations of isopod populations have resulted in regional declines and in greatly reduced population connectivity in several major littoral cells of southern California. Two of the six major littoral cells (Santa Barbara and Zuma) in the area currently support 74% of the remaining isopod populations. These isopods persist primarily on relatively remote, ungroomed, unarmored beaches with restricted vehicle access and minimal management activity. These predominantly narrow, bluff-backed beaches also support species-rich upper beach assemblages, suggesting these isopods can be useful indicators of biodiversity. The high extirpation rates of isopod populations on the southern California mainland over the last century provide a compelling example of the vulnerability of upper beach invertebrates to coastal urbanization. Climate change and sea level rise will exert further pressures on upper beach zones and biota in southern California and globally. In the absence of rapid implementation of effective conservation strategies, our results suggest many upper intertidal invertebrate species are at risk.

Evidence for an upper mantle low velocity zone beneath the southern Basin and Range-Colorado Plateau transition zone

USGS Publications Warehouse

Benz, H.M.; McCarthy, J.

1994-01-01

A 370-km-long seismic refraction/wide-angle reflection profile recorded during the Pacific to Arizona Crustal Experiment (PACE) detected an upper mantle P-wave low-velocity zone (LVZ) in the depth range 40 to 55 km beneath the Basin and Range in southern Arizona. Interpretation of seismic data places constraints on the sub-crustal lithosphere of the southern Basin and Range Province, which is important in light of the active tectonics of the region and the unknown role of the sub-crustal lithosphere in the development of the western United States. Forward travel time and synthetic seismogram techniques are used to model this shallow upper mantle LVZ. Modeling results show that the LVZ is defined by a 5% velocity decrease relative to a Pn velocity of 7.95 km s−1, suggesting either a ∼3–5% mafic partial melt or high-temperature, sub-solidus peridotite.

Seismicity in the platform regions of Ukraine in the zones of anomalous electrical conductivity

NASA Astrophysics Data System (ADS)

Kushnir, A. N.; Kulik, S. N.; Burakhovich, T. K.

2013-05-01

It is established for the first time that there are several regions in Ukraine, in which the earthquakes occurring within platform territory are correlated to the anomalous conductive structures in the Earth's crust and upper mantle. These regions are identified as (1) Donbass and the eastern part of the Dnieper-Donetsk Depression (DDD); (2) eastern margin of the Ingulets-Krivoi Rog suture zone in the area of the Krivoi Rog-Kremenchug fault zone; (3) the western part of the Cis-Azov megablock; (4) the western boundary of the Ukrainian Shield and its slope; (5) North Dobruja and Pre-Dobrujan Depression. The reconstructed tree-dimensional (3D) geoelectrical models of the Earth's crust and upper mantle feature anomalously low values of electric resistivity. The earthquake sources in the platform areas of Ukraine are localized above the top and in the upper parts of the crustal anomalies of electrical conductivity.

Paleogeographic implications of an erosional remnant of Paleogene rocks southwest of the Sur-Nacimiento Fault Zone, southern Coast Ranges, California

USGS Publications Warehouse

Vedder, J.G.; McLean, H.; Stanley, R.G.; Wiley, T.J.

1991-01-01

A small tract of heretofore-unrecognized Paleogene rocks lies about 30 km northeast of Santa Maria and 1 km southwest of the Sur-Nacimiento fault zone near upper Pine Creek. This poorly exposed assemblage of rocks is less than 50 m thick, lies unconformably on regionally distributed Upper Cretaceous submarine-fan deposits, and consists of three units: fossiliferous lower Eocene mudstone, Oligocene(?) conglomerate, and basaltic andesite that has a radiometric age of 26.6 ?? 0.5 Ma. Both the sedimentary and igneous constituents in the Paleogene sequence are unlike those of known sequences on either side of the Sur-Nacimiento fault zone. The Paleogene sedimentary rocks near upper Pine Creek presumably are remnants of formerly widespread early Eocene bathyal deposits and locally distributed Oligocene(?) fluvial deposits southwest of the fault zone. The 26.6 Ma basaltic andesite, however, may not have extended much beyond its present outcrops. An episode of Oligocene(?) displacement is required by the contrast in thicknesses, depositional patterns, and paleobathymetry of the juxtaposed rock sequences. -from Authors

The pectinate zone is stiff and the arcuate zone determines passive basilar membrane mechanics in the gerbil

NASA Astrophysics Data System (ADS)

Xia, Hongyi; Steele, Charles R.; Puria, Sunil

2018-05-01

The gerbil basilar membrane (BM) differs from other mammalian BMs in that the lower collagen-fiber layer of the pectinate zone (PZ) forms an arch, the upper fiber layer is flat, and ground substance separates the two layers. The role of this arch has been unknown, but can be elucidated by models. In the standard simple beam model (SBM), the upper and lower collagen-fiber layers of the BM are represented as a single layer in both the PZ and the arcuate zone (AZ). In our new arch-beam model (ABM), the upper fiber layer is flat, the lower layer forms an arch in the PZ, and the two layers combine to form the flat portion of the BM in the AZ. This design is incorporated into a 3D finite-element tapered-box model of the cochlea with viscous fluid. We find in the model that the PZ rotates as a rigid body, so its specific properties have little influence, while the AZ thickness and collagen volume fraction primarily determine passive BM mechanics.

Crystal accumulation and compositional trends in a calc-alkaline batholith: implications for correlation of plutonic and volcanic rocks

NASA Astrophysics Data System (ADS)

Barnes, C. G.; Coint, N.

2013-12-01

The Wooley Creek batholith is a tilted, calc-alkaline intrusive complex in the Klamath Mountain province, California, that can be divided into two main zones: lower (~159.2 × 0.2 Ma) and upper (~158.2 × 0.3 Ma), separated by a central transition zone. The lower zone consists of multiple intrusive units of gabbro through tonalite, with minor mafic synplutonic dikes and intrusive melagabbro and pyroxenite. Major and trace element data plot in two groups: a mafic group that encompasses pyroxenite to diorite, and a tonalitic group. For each group, Mg/Fe in augite was used to determine the approximate composition of equilibrium melt and then major element mass balance was used to calculate proportions of cumulate phases and melt. For the mafic group, no single parental magma can be identified, which is consistent with assembly via many magma batches. However, the most mafic rocks were derived from basaltic andesite magmas and represent 30 to 100% cumulate augite + opx × plagioclase × olivine. Interstitial melt in the tonalitic group was dacitic, and mass balance indicates from 30 to 80% cumulate pyroxenes + plagioclase × accessory apatite and Fe-Ti oxides. The parental magma was probably silicic andesite. The upper zone varies gradationally from structurally low quartz diorite to uppermost granite. Upper zone magmas ';leaked' to form dacitic to rhyodacitic ';roof dikes'. Previous work (Coint et al., Geosphere, in press) showed that the upper zone formed from an approximately homogeneous magma body and that compositional variation was related to upward percolation of melt. Mass balance supports this interpretation and indicates that (1) the parental magmas were andesitic, (2) structurally low rocks are 15 to 65 % cumulate hornblende + plagioclase × pyroxene, and (3) high-level granite and granodiorite are the fractionated products of this accumulation. These results show that the upper zone is a good example of fractional crystallization within a moderate-sized magma body (≥ 160 km3) in which both cumulates and differentiates are readily identified. In contrast, differentiates related to lower-zone cumulate rocks are rare, presumably because they intruded higher crustal levels and/or erupted. We conclude that compositional trends of lower-zone rocks are dominated by crystal accumulation and do not accurately reflect magmatic evolution owing to loss of differentiated magmas. If this process is common in such plutons, then the use of bulk-rock compositions to identify consanguineous plutonic and volcanic rocks will be difficult, at best.

Validation of Body Volume Acquisition by Using Elliptical Zone Method.

PubMed

Chiu, C-Y; Pease, D L; Fawkner, S; Sanders, R H

2016-12-01

The elliptical zone method (E-Zone) can be used to obtain reliable body volume data including total body volume and segmental volumes with inexpensive and portable equipment. The purpose of this research was to assess the accuracy of body volume data obtained from E-Zone by comparing them with those acquired from the 3D photonic scanning method (3DPS). 17 male participants with diverse somatotypes were recruited. Each participant was scanned twice on the same day by a 3D whole-body scanner and photographed twice for the E-Zone analysis. The body volume data acquired from 3DPS was regarded as the reference against which the accuracy of the E-Zone was assessed. The relative technical error of measurement (TEM) of total body volume estimations was around 3% for E-Zone. E-Zone can estimate the segmental volumes of upper torso, lower torso, thigh, shank, upper arm and lower arm accurately (relative TEM<10%) but the accuracy for small segments including the neck, hand and foot were poor. In summary, E-Zone provides a reliable, inexpensive, portable, and simple method to obtain reasonable estimates of total body volume and to indicate segmental volume distribution. © Georg Thieme Verlag KG Stuttgart · New York.

Aerobic Microbial Respiration in Oceanic Oxygen Minimum Zones

NASA Astrophysics Data System (ADS)

Kalvelage, Tim; Lavik, Gaute; Jensen, Marlene M.; Revsbech, Niels Peter; Schunck, Harald; Loescher, Carolin; Desai, Dhwani K.; LaRoche, Julie; Schmitz-Streit, Ruth; Kuypers, Marcel M. M.

2014-05-01

In the oxygen minimum zones (OMZs) of the tropical oceans, sluggish ventilation combined with strong microbial respiration of sinking organic matter results in the depletion of oxygen (O2). When O2 concentrations drop below ~5 µmol/L, organic matter is generally assumed to be respired with nitrate, ultimately leading to the loss of fixed inorganic nitrogen via anammox and denitrification. However, direct measurements of microbial O2 consumption at low O2 levels are - apart from a single experiment conducted in the OMZ off Peru - so far lacking. At the same time, consistently observed active aerobic ammonium and nitrite oxidation at non-detectable O2 concentrations (<1 µmol/L) in all major OMZs, suggests aerobic microorganisms, likely including heterotrophs, to be well adapted to near-anoxic conditions. Consequently, microaerobic (≤5 µmol/L) remineralization of organic matter, and thus release of ammonium, in low- O2 environments might be significantly underestimated at present. Here we present extensive measurements of microbial O2 consumption in OMZ waters, combined with highly sensitive O2 (STOX) measurements and meta-omic functional gene analyses. Short-term incubation experiments with labelled O2 (18-18O2) carried out in the Namibian and Peruvian OMZ, revealed persistent aerobic microbial activity at depths with non-detectable concentrations of O2 (≤50 nmol/L). In accordance, examination of metagenomes and metatranscriptomes from Chilean and Peruvian OMZ waters identified genes encoding for terminal respiratory oxidases with high O2 affinities as well as their expression by diverse microbial communities. Oxygen consumption was particularly enhanced near the upper OMZ boundaries and could mostly (~80%) be assigned to heterotrophic microbial activity. Compared to previously identified anaerobic microbial processes, microaerobic organic matter respiration was the dominant remineralization pathway and source of ammonium (~90%) in the upper Namibian and Peruvian OMZ. Our results reconcile so-far existing mismatches between ammonium sources and sinks in OMZs, and may help to improve biogeochemical modelling of the effects of future ocean de-oxygenation on aerobic and anaerobic organic matter remineralization in these zones.

Widespread imaging of the lower crust, Moho, and upper mantle from Rayleigh waves: A comparison of the Cascadia and Aleutian-Alaska subduction zones

NASA Astrophysics Data System (ADS)

Haney, M. M.; Tsai, V. C.; Ward, K. M.

2016-12-01

Recently, Haney and Tsai (2015) developed a new approach to Rayleigh-wave inversion based on assumptions that are similar to those used in the formulation of the Dix equation in reflection seismology. Here we apply the Dix technique to Rayleigh-wave phase-velocity maps by Ekstrom (2013) and Ward (2015) of the contiguous US and Alaska, respectively, at periods between 12 and 45 s. We refine the initial Dix result with subsequent nonlinear inversion to estimate Moho depth together with shear-wave velocity of the lower crust and upper mantle. In the contiguous US, the Moho we image agrees well with recent receiver function studies. There is an apparent deepening of the Moho to the west of the Cascades volcanic chain that we interpret as the waveguide interface transitioning to the slab due to the continental Moho becoming transparent above the mantle forearc. This feature abruptly terminates at the southern extent of the Cascadia subduction zone. We compare the depths of this "apparent Moho" with published estimates of the depth to the Juan de Fuca Plate since, owing to the paucity of tectonic earthquakes, the Slab1.0 model is not defined in Cascadia. Our result in Alaska is the first regional Moho map derived explicitly from seismic waves. We find that crustal thickness is generally correlated with topography, with thicker crust beneath mountain ranges in southern Alaska. North of the Denali Fault, the Moho is smoother than to the south and located at typical depths of 30-35 km. There are also indications that the waveguide interface we solve for beneath Prince William Sound is actually the subducting slab instead of the continental Moho. The slab structure beneath Prince William Sound extends further east than the Pacific slab represented in the Slab1.0 model. Using the limited number of broadband seismometers in the Aleutian Islands, we obtain preliminary estimates for the crustal structure beneath the western portion of the Aleutian-Alaska subduction zone.

Least-cost control of agricultural nutrient contributions to the Gulf of Mexico hypoxic zone

USDA-ARS?s Scientific Manuscript database

In 2007, the hypoxic zone in the Gulf of Mexico, measuring 20,720 km**2, was one of the two largest reported since measurement of the zone began in 1985. The extent of the hypoxic zone is related to nitrogen and phosphorous loadings originating on agricultural fields in the upper Midwest. This stud...

Comparative velocity structure of active Hawaiian volcanoes from 3-D onshore-offshore seismic tomography

USGS Publications Warehouse

Park, J.; Morgan, J.K.; Zelt, C.A.; Okubo, P.G.; Peters, L.; Benesh, N.

2007-01-01

We present a 3-D P-wave velocity model of the combined subaerial and submarine portions of the southeastern part of the Island of Hawaii, based on first-arrival seismic tomography of marine airgun shots recorded by the onland seismic network. Our model shows that high-velocity materials (6.5-7.0??km/s) lie beneath Kilauea's summit, Koae fault zone, and the upper Southwest Rift Zone (SWRZ) and upper and middle East Rift Zone (ERZ), indicative of magma cumulates within the volcanic edifice. A separate high-velocity body of 6.5-6.9??km/s within Kilauea's lower ERZ and upper Puna Ridge suggests a distinct body of magma cumulates, possibly connected to the summit magma cumulates at depth. The two cumulate bodies within Kilauea's ERZ may have undergone separate ductile flow seaward, influencing the submarine morphology of Kilauea's south flank. Low velocities (5.0-6.3??km/s) seaward of Kilauea's Hilina fault zone, and along Mauna Loa's seaward facing Kao'iki fault zone, are attributed to thick piles of volcaniclastic sediments deposited on the submarine flanks. Loihi seamount shows high-velocity anomalies beneath the summit and along the rift zones, similar to the interpreted magma cumulates below Mauna Loa and Kilauea volcanoes, and a low-velocity anomaly beneath the oceanic crust, probably indicative of melt within the upper mantle. Around Kilauea's submarine flank, a high-velocity anomaly beneath the outer bench suggests the presence of an ancient seamount that may obstruct outward spreading of the flank. Mauna Loa's southeast flank is also marked by a large, anomalously high-velocity feature (7.0-7.4??km/s), interpreted to define an inactive, buried volcanic rift zone, which might provide a new explanation for the westward migration of Mauna Loa's current SWRZ and the growth of Kilauea's SWRZ. ?? 2007 Elsevier B.V. All rights reserved.

Method of making high breakdown voltage semiconductor device

DOEpatents

Arthur, Stephen D.; Temple, Victor A. K.

1990-01-01

A semiconductor device having at least one P-N junction and a multiple-zone junction termination extension (JTE) region which uniformly merges with the reverse blocking junction is disclosed. The blocking junction is graded into multiple zones of lower concentration dopant adjacent termination to facilitate merging of the JTE to the blocking junction and placing of the JTE at or near the high field point of the blocking junction. Preferably, the JTE region substantially overlaps the graded blocking junction region. A novel device fabrication method is also provided which eliminates the prior art step of separately diffusing the JTE region.

Presynaptic Active Zone Density during Development and Synaptic Plasticity.

PubMed

Clarke, Gwenaëlle L; Chen, Jie; Nishimune, Hiroshi

2012-01-01

Neural circuits transmit information through synapses, and the efficiency of synaptic transmission is closely related to the density of presynaptic active zones, where synaptic vesicles are released. The goal of this review is to highlight recent insights into the molecular mechanisms that control the number of active zones per presynaptic terminal (active zone density) during developmental and stimulus-dependent changes in synaptic efficacy. At the neuromuscular junctions (NMJs), the active zone density is preserved across species, remains constant during development, and is the same between synapses with different activities. However, the NMJ active zones are not always stable, as exemplified by the change in active zone density during acute experimental manipulation or as a result of aging. Therefore, a mechanism must exist to maintain its density. In the central nervous system (CNS), active zones have restricted maximal size, exist in multiple numbers in larger presynaptic terminals, and maintain a constant density during development. These findings suggest that active zone density in the CNS is also controlled. However, in contrast to the NMJ, active zone density in the CNS can also be increased, as observed in hippocampal synapses in response to synaptic plasticity. Although the numbers of known active zone proteins and protein interactions have increased, less is known about the mechanism that controls the number or spacing of active zones. The following molecules are known to control active zone density and will be discussed herein: extracellular matrix laminins and voltage-dependent calcium channels, amyloid precursor proteins, the small GTPase Rab3, an endocytosis mechanism including synaptojanin, cytoskeleton protein spectrins and β-adducin, and a presynaptic web including spectrins. The molecular mechanisms that organize the active zone density are just beginning to be elucidated.

Presynaptic Active Zone Density during Development and Synaptic Plasticity

PubMed Central

Clarke, Gwenaëlle L.; Chen, Jie; Nishimune, Hiroshi

2012-01-01

Neural circuits transmit information through synapses, and the efficiency of synaptic transmission is closely related to the density of presynaptic active zones, where synaptic vesicles are released. The goal of this review is to highlight recent insights into the molecular mechanisms that control the number of active zones per presynaptic terminal (active zone density) during developmental and stimulus-dependent changes in synaptic efficacy. At the neuromuscular junctions (NMJs), the active zone density is preserved across species, remains constant during development, and is the same between synapses with different activities. However, the NMJ active zones are not always stable, as exemplified by the change in active zone density during acute experimental manipulation or as a result of aging. Therefore, a mechanism must exist to maintain its density. In the central nervous system (CNS), active zones have restricted maximal size, exist in multiple numbers in larger presynaptic terminals, and maintain a constant density during development. These findings suggest that active zone density in the CNS is also controlled. However, in contrast to the NMJ, active zone density in the CNS can also be increased, as observed in hippocampal synapses in response to synaptic plasticity. Although the numbers of known active zone proteins and protein interactions have increased, less is known about the mechanism that controls the number or spacing of active zones. The following molecules are known to control active zone density and will be discussed herein: extracellular matrix laminins and voltage-dependent calcium channels, amyloid precursor proteins, the small GTPase Rab3, an endocytosis mechanism including synaptojanin, cytoskeleton protein spectrins and β-adducin, and a presynaptic web including spectrins. The molecular mechanisms that organize the active zone density are just beginning to be elucidated. PMID:22438837

A deep crustal fluid channel into the San Andreas Fault system near Parkfield, California

USGS Publications Warehouse

Becken, M.; Ritter, O.; Park, S.K.; Bedrosian, P.A.; Weckmann, U.; Weber, M.

2008-01-01

Magnetotelluric (MT) data from 66 sites along a 45-km-long profile across the San Andreas Fault (SAF) were inverted to obtain the 2-D electrical resistivity structure of the crust near the San Andreas Fault Observatory at Depth (SAFOD). The most intriguing feature of the resistivity model is a steeply dipping upper crustal high-conductivity zone flanking the seismically defined SAF to the NE, that widens into the lower crust and appears to be connected to a broad conductivity anomaly in the upper mantle. Hypothesis tests of the inversion model suggest that upper and lower crustal and upper-mantle anomalies may be interconnected. We speculate that the high conductivities are caused by fluids and may represent a deep-rooted channel for crustal and/or mantle fluid ascent. Based on the chemical analysis of well waters, it was previously suggested that fluids can enter the brittle regime of the SAF system from the lower crust and mantle. At high pressures, these fluids can contribute to fault-weakening at seismogenic depths. These geochemical studies predicted the existence of a deep fluid source and a permeable pathway through the crust. Our resistivity model images a conductive pathway, which penetrates the entire crust, in agreement with the geochemical interpretation. However, the resistivity model also shows that the upper crustal branch of the high-conductivity zone is located NE of the seismically defined SAF, suggesting that the SAF does not itself act as a major fluid pathway. This interpretation is supported by both, the location of the upper crustal high-conductivity zone and recent studies within the SAFOD main hole, which indicate that pore pressures within the core of the SAF zone are not anomalously high, that mantle-derived fluids are minor constituents to the fault-zone fluid composition and that both the volume of mantle fluids and the fluid pressure increase to the NE of the SAF. We further infer from the MT model that the resistive Salinian block basement to the SW of the SAFOD represents an isolated body, being 5-8km wide and reaching to depths >7km, in agreement with aeromagnetic data. This body is separated from a massive block of Salinian crust farther to the SW. The NE terminus of resistive Salinian crust has a spatial relationship with a near-vertical zone of increased seismic reflectivity ???15km SW of the SAF and likely represents a deep-reaching fault zone. ?? 2008 The Authors Journal compilation ?? 2008 RAS.

Summary of hydrologic testing of the Floridan aquifer system at Hunter Army Airfield, Chatham County, Georgia

USGS Publications Warehouse

Williams, Lester J.

2010-01-01

A 1,168-foot deep test well was completed at Hunter Army Airfield in the summer of 2009 to investigate the potential of using the Lower Floridan aquifer as a source of water supply to satisfy increased needs as a result of base expansion and increased troop levels. The U.S. Geological Survey conducted hydrologic testing at the test site including flowmeter surveys, packer-slug tests, and aquifer tests of the Upper and Lower Floridan aquifers. Flowmeter surveys were completed at different stages of well construction to determine the depth and yield of water-bearing zones and to identify confining beds that separate the main producing aquifers. During a survey when the borehole was open to both the upper and lower aquifers, five water-bearing zones in the Upper Floridan aquifer supplied 83.5 percent of the total pumpage, and five water-bearing zones in the Lower Floridan aquifer supplied the remaining 16.5 percent. An upward gradient was indicated from the ambient flowmeter survey: 7.6 gallons per minute of groundwater was detected entering the borehole between 750 and 1,069 feet below land surface, then moved upward, and exited the borehole into lower-head zones between 333 and 527 feet below land surface. During a survey of the completed Lower Floridan well, six distinct water-producing zones were identified; one 17-foot-thick zone at 768-785 feet below land surface yielded 47.9 percent of the total pumpage while the remaining five zones yielded between 2 and 15 percent each. The thickness and hydrologic properties of the confining unit separating the Upper and Lower Floridan aquifers were determined from packer tests and flowmeter surveys. This confining unit, which is composed of rocks of Middle Eocene age, is approximately 160 feet thick with horizontal hydraulic conductivities determined from four slug tests to range from 0.2 to 3 feet per day. Results of two separate slug tests within the middle confining unit were both 2 feet per day. Aquifer testing indicated the Upper Floridan aquifer had a transmissivity of 40,000 feet squared per day, and the Lower Floridan aquifer had a transmissivity of 10,000 feet squared per day. An aquifer test conducted on the combined aquifer system, when the test well was open from 333 to 1,112 feet, gave a transmissivity of 50,000 feet squared per day. Additionally, during the 72-hour test of the Lower Floridan aquifer, a drawdown response was observed in the Upper Floridan aquifer wells.

49 CFR 372.221 - Twin Cities.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Twin Cities. 372.221 Section 372.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... ZONES, AND TERMINAL AREAS Commercial Zones § 372.221 Twin Cities. For the purpose of determining...

49 CFR 372.221 - Twin Cities.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Twin Cities. 372.221 Section 372.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... ZONES, AND TERMINAL AREAS Commercial Zones § 372.221 Twin Cities. For the purpose of determining...

49 CFR 372.221 - Twin Cities.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Twin Cities. 372.221 Section 372.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... ZONES, AND TERMINAL AREAS Commercial Zones § 372.221 Twin Cities. For the purpose of determining...

78 FR 76594 - Reorganization and Expansion of Foreign-Trade Zone 146 Under Alternative Site Framework Lawrence...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-18

... and 2 would be categorized as magnet sites, and the grantee proposes an initial usage-driven site... the zone, to a five-year ASF sunset provision for magnet sites that would terminate authority for...

77 FR 32929 - Grant of Authority; Establishment of a Foreign-Trade Zone Under the Alternative Site Framework...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-04

... be categorized as magnet sites; Whereas, notice inviting public comment has been given in the Federal...-purpose zone project, and to an ASF sunset provision for magnet sites that would terminate authority for...

78 FR 52759 - Expansion of Foreign-Trade Zone 75 Under Alternative Site Framework; Phoenix, Arizona

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-26

..., docketed 12-07-2012) for authority to expand the zone under the ASF to include an additional magnet site...-year ASF sunset provision for magnet sites that would terminate authority for Site 9 if not activated...

Triggering effect of mining at different horizons in the rock mass with excavations. Mathematical modeling

NASA Astrophysics Data System (ADS)

Eremin, M. O.; Makarov, P. V.

2017-12-01

On the basis of a quite simple structural model of rock mass, containing coal seams on two horizons, coal mining is numerically modeled. A finite difference numerical technique is applied. At first, mining starts at the upper horizon and then moves to the lower horizon. It is shown that a mining process at the lower horizon has a significant triggering influence on the growth of damage zones in the roof and floor at the upper horizon. The features of spatiotemporal migration of deformation activity are studied numerically. Foci of large-scale fracture are located at the boundary of the seismic silence zone and the zone where the deformation activity migrates. This boundary has an additional characteristic: the maximum gradient of rock pressure is observed in this zone.

Three-dimensional mapping of extrusive layer at the East Pacific Rise 9°50'N

NASA Astrophysics Data System (ADS)

Marjanovic, M.; Stopin, A.; Plessix, R. E.; Singh, S. C.

2017-12-01

The East Pacific Rise (EPR) is one of the most active portion of Mid-Ocean Ridge system along which 6 km thick oceanic crust has been forming. The upper part of thus formed crust is represented by basalts (layer 2A) and dikes (layer 2B). In velocity models, the layer 2A/2B boundary is characterized by a velocity gradient, which is attributed to change in porosity. The geologic nature of the gradient is debated, with the two prevailing explanations: lithological contact between basalts and dikes, or alteration front due to hydrothermal circulation. In addition, 2D seismic sections suggested rapid thickening of the topmost layer within a few km from the ridge axis. Due to limited information on the upper crustal velocities it has been unclear if this observation is due to physical thickening of the extrusive layer or it is a result of downward propagating, hydrothermally driven, cracking front. To add some of the missing constrains, we apply elastic 3D full waveform inversion technique to 3D seismic dataset collected at the EPR. The final 3D velocity model of the upper crust covers area 44x55 km2, and is obtained after 15, multiparameter inversions of low frequencies. The layer 2A/2B boundary is clearly identified in the resulting model as the base of high velocity gradient and can be followed throughout the entire area included in the inversion; consistency in character of the gradient zone and distinct velocity anomaly near active hydrothermal discharge zones, where the most of the alteration is expected to take place, argue that this boundary is predominantly lithological and that the layer 2A thickening is due to emplacement of lava off the innermost axial zone. The transition from thin (150-200 m) to thick (300-550 m) layer 2A occurs within a narrow band around the ridge axis (0.5-2.5 km). This band is wider between 9º48-53', and highly asymmetric, with almost vertical side on the Pacific and gentle dipping side on the Cocos Plate, terminating at the contact with ridge parallel, inward facing faults. Beyond the faults, layer 2A attains almost constant thickness. By combining the available observables and results of our analyses we suggest that the emplacement of extrusives, variation in their thickness, and rate of dike subsidence are predominantly controlled by tectono-magmatic features and processes operating near the ridge axis.

The Devils Mountain Fault zone: An active Cascadia upper plate zone of deformation, Pacific Northwest of North America

NASA Astrophysics Data System (ADS)

Barrie, J. Vaughn; Greene, H. Gary

2018-02-01

The Devils Mountain Fault Zone (DMFZ) extends east to west from Washington State to just south of Victoria, British Columbia, in the northern Strait of Juan de Fuca of Canada and the USA. Recently collected geophysical data were used to map this fault zone in detail, which show the main fault trace, and associated primary and secondary (conjugate) strands, and extensive northeast-southwest oriented folding that occurs within a 6 km wide deformation zone. The fault zone has been active in the Holocene as seen in the offset and disrupted upper Quaternary strata, seafloor displacement, and deformation within sediment cores taken close to the seafloor expression of the faults. Data suggest that the present DMFZ and the re-activated Leech River Fault may be part of the same fault system. Based on the length and previously estimated slip rates of the fault zone in Washington State, the DMFZ appears to have the potential of producing a strong earthquake, perhaps as large as magnitude 7.5 or greater, within 2 km of the city of Victoria.

Preliminary appraisal of the geohydrologic aspects of drainage wells, Orlando area, central Florida

USGS Publications Warehouse

Kimrey, Joel O.

1978-01-01

The Floridan aquifer contains two highly transmissive cavernous zones in the Orlando area: an upper producing zone about 150-600 feet below land surface; and a lower producing zone about 1,100-1,500 feet below land surface. Natural head differences are downward and there is hydraulic connection between the two producing zones. Drainage wells are finished open-end into the upper producing zone and emplace surface waters directly into that zone by gravity. Quantitatively, their use constitutes an effective method of artificial recharge. Their negative aspects relate to the probably poor, but unknown, quality of the recharge water. Caution is suggested in drawing definite and final conclusions on the overall geohydrologic and environmental effects of drainage wells prior to the collection and interpretation of a considerable quantity of new data. Though few ground-water pollution problems have been documented to date, the potential for such pollution should be seriously considered in light of the prob-able continuing need to use drainage wells; the probable volumes and quality of water involved; and the hydraulic relations between the two producing zones.

Cretaceous planktic foraminiferal biostratigraphy of the Calera Limestone, Northern California, USA

USGS Publications Warehouse

Sliter, W.V.

1999-01-01

The Calera Limestone is the largest, most stratigraphically extensive limestone unit of oceanic character included in the Franciscan Complex of northern California. The aim of this paper is to place the Calera Limestone at its type locality (Rockaway Beach, Pacifica) in a high-resolution biostratigraphy utilizing planktic foraminifers studied in thin section. A section, about 110 m-thick, was measured from the middle thrust slice exposed by quarrying on the southwest side of Calera Hill at Pacifica Quarry. Lithologically, the section is divided in two units; a lower unit with 73 m of black to dark-grey limestone, black chert and tuff, and an upper unit with 36.8 m of light-grey limestone and medium-grey chert. Two prominent black-shale layers rich in organic carbon occur 11 m below the top of the lower black unit and at the boundary with overlying light-grey unit, yielding a total organic content (TOC) of 4.7% and 1.8% t.w., respectively. The fossiliferous Calera Limestone section measured at Pacifica Quarry, from the lower black shale, contains eleven zones and three subzones that span approximately 26 m.y. from the early Aptian to the late Cenomanian. The zones indentified range from the Globigerinelloides blowi Zone to the Dicarinella algeriana Subzone of the Rotalipora cushmani Zone. Within this biostratigraphic interval, the Ticinella bejaouaensis and Hedbergella planispira Zones at the Aptian/Albian boundary are missing as are the Rotalipora subticinensis Subzone of the Biticinella breggiensis Zone and the overlying Rotalipora ticinensis Zone in the late Albian owing both to low-angle thrust faulting and to unconformities. The abundance and preservation of planktic foraminifers are poor in the lower part and improve only within the upper G. algerianus Zone. The faunal relationship indicate that the lower black shale occurs in the upper part of the G. blowi Zone and correlates with the Selli Event recognized at global scale in the early Aptian. The upper black shale occurs at or near the boundary between the G. ferreolensis and G. algerianus Zone in the late Aptian. This black layer, or Thalmann Event as named here, seems to represent the sedimentary expression, at the scale of Permanente Terrane, of a global perturbation of the carbon cycle.

Sandbox Simulations of the Evolution of a Subduction Wedge following Subduction Initiation

NASA Astrophysics Data System (ADS)

Brandon, M. T.; Ma, K. F.; DeWolf, W.

2012-12-01

Subduction wedges at accreting subduction zones are bounded by a landward dipping pro-shear zone (= subduction thrust) and a seaward-dipping retro-shear zone in the overriding plate. For the Cascadia subduction zone, the surface trace of the retro-shear zone corresponds to the east side of the Coast Ranges of Oregon and Washington and the Insular Mountains of Vancouver Island. This coastal high or forearc high shows clear evidence of long-term uplift and erosion along its entire length, indicating that it is an active part of the Cascadia subduction wedge. The question addressed here is what controls the location of the retro-shear zone? In the popular double-sided wedge model of Willet et al (Geology 1993), the retro-shear zone remains pinned to the S point, which is interpreted to represent where the upper-plate Moho intersects the subduction zone. For this interpretation, the relatively strong mantle is considered to operate as a flat backstop. That model, however. is somewhat artificial in that the two plates collide in a symmetric fashion with equal crustal thicknesses on both sides. Using sandbox experiments, we explore a more realistic configuration where the upper and lower plate are separated by a gentle dipping (10 degree) pro-shear zone, to simulate the initial asymmetric geometry of the subduction thrust immediately after initiation of subduction. The entire lithosphere must fail along some plane for subduction to begin and this failure plane must dip in the direction of subduction. Thus, the initial geometry of the overriding plate is better approximated as a tapered wedge than as a layer of uniform thickness, as represented in the Willett et al models. We demonstrate this model using time-lapse movies of a sand wedge above a mylar subducting plate. We use particle image velocimetry (PIV) to show the evolution of strain and structure within the overriding plate. Material accreted to the tapered end of the overriding plate drives deformation and causes the retro-shear zone to propagate rearward with time. The main conclusion is that the rearward propagation will cease only when 1) the retro shear zone reaches the S point (i.e. the mantle cutoff in the upper plate) or 2) the erosion outflux from the subduction wedge matches the accretionary influx. Given the location of the upper plate Moho at Cascadia, it seems that erosion is the control factor in pinning the retro shear zone there.

Tectonic and Structural Controls of Geothermal Activity in the Great Basin Region, Western USA

NASA Astrophysics Data System (ADS)

Faulds, J. E.; Hinz, N.; Kreemer, C. W.

2012-12-01

We are conducting a thorough inventory of structural settings of geothermal systems (>400 total) in the extensional to transtensional Great Basin region of the western USA. Most of the geothermal systems in this region are not related to upper crustal magmatism and thus regional tectonic and local structural controls are the most critical factors controlling the locations of the geothermal activity. A system of NW-striking dextral faults known as the Walker Lane accommodates ~20% of the North American-Pacific plate motion in the western Great Basin and is intimately linked to N- to NNE-striking normal fault systems throughout the region. Overall, geothermal systems are concentrated in areas with the highest strain rates within or proximal to the eastern and western margins of the Great Basin, with the high temperature systems clustering in transtensional areas of highest strain rate in the northwestern Great Basin. Enhanced extension in the northwestern Great Basin probably results from the northwestward termination of the Walker Lane and the concomitant transfer of dextral shear into west-northwest directed extension, thus producing a broad transtensional region. The capacity of geothermal power plants also correlates with strain rates, with the largest (hundreds of megawatts) along the Walker Lane or San Andreas fault system, where strain rates range from 10-100 nanostrain/yr to 1,000 nanostrain/yr, respectively. Lesser systems (tens of megawatts) reside in the Basin and Range (outside the Walker Lane), where local strain rates are typically < 10 nanostrain/yr. Of the 250+ geothermal fields catalogued, step-overs or relay ramps in normal fault zones serve as the most favorable setting, hosting ~32% of the systems. Such areas have multiple, overlapping fault strands, increased fracture density, and thus enhanced permeability. Other common settings include a) intersections between normal faults and strike-slip or oblique-slip faults (27%), where multiple minor faults connect major structures and fluids can flow readily through highly fractured, dilational quadrants, and b) normal fault terminations or tip-lines (22%), where horse-tailing generates closely-spaced faults and increased permeability. Other settings include accommodation zones (i.e., belts of intermeshing, oppositely dipping normal faults; 8%), major range-front faults (5-6%), and pull-aparts in strike-slip faults (4%). In addition, Quaternary faults lie within or near most systems. The relative scarcity of geothermal systems along displacement-maxima of major normal faults may be due to reduced permeability in thick zones of clay gouge and periodic release of stress in major earthquakes. Step-overs, terminations, intersections, and accommodation zones correspond to long-term, critically stressed areas, where fluid pathways are more likely to remain open in networks of closely-spaced, breccia-dominated fractures. These findings may help guide future exploration efforts, especially for blind geothermal systems, which probably comprise the bulk of the geothermal resources in the Great Basin.

The effect of potassium on exocytosis of transmitter at the frog neuromuscular junction.

PubMed Central

Ceccarelli, B; Fesce, R; Grohovaz, F; Haimann, C

1988-01-01

1. Electrophysiology and morphology have been combined to investigate the time course of the exocytosis of quanta of neurotransmitter induced by elevated concentrations of K+ at the frog neuromuscular junction. 2. Replicas of freeze-fractured resting nerve terminals fixed in the presence of 20 mM-K+ showed images of fusion of synaptic vesicles with the presynaptic axolemma which were closely associated with the active zones. After 1 min in 20 nM-K+ fusions appeared also outside the active zones, and by 5 min they became uniformly distributed over the presynaptic membrane. 3. The average total density of fusions was not significantly different at the various times examined since it decreased at the active zones while it increased over the rest of the membrane. 4. Resting terminals fixed in 20 mM-K+ released 33,000-45,000 quanta after the addition of fixative; terminals stimulated by 20 mM-K+ for 1-5 min released 50,000-100,000 quanta during fixation. The fixative potentiated K+-induced transmitter release. 5. Fusions were uniformly distributed in terminals pre-incubated for 5 min in 20 mM-K+ without added Ca2+, stimulated by adding Ca2+ for 30 s, and then fixed. Conversely, after 5 min stimulation in hypertonic Ringer solution fusions remained predominantly located near the active zones. A similar distribution was observed after 15 min stimulation by a lower concentration of K+ (15 mM). 6. At all concentrations of K+ tested (10, 15, 20, 25 mM) miniature end-plate potential (MEPP) rate attained a steady-state value within 10-15 min. Values from a single junction were generally lower at higher concentrations of K+, which indicates partial inactivation of the secretion-recycling process. 7. The data indicate that K+ initially activates exocytosis at the active zones. Subsequently, ectopic exocytosis is activated while sites at the active zones appear to undergo partial inactivation. These phenomena are not related to the intensity or to the amount of previous secretion. Images Fig. 1 Fig. 2 Fig. 3 Fig. 8 Fig. 10 PMID:2902217

Seasonality and vertical structure of microbial communities in an ocean gyre.

PubMed

Treusch, Alexander H; Vergin, Kevin L; Finlay, Liam A; Donatz, Michael G; Burton, Robert M; Carlson, Craig A; Giovannoni, Stephen J

2009-10-01

Vertical, seasonal and geographical patterns in ocean microbial communities have been observed in many studies, but the resolution of community dynamics has been limited by the scope of data sets, which are seldom up to the task of illuminating the highly structured and rhythmic patterns of change found in ocean ecosystems. We studied vertical and temporal patterns in the microbial community composition in a set of 412 samples collected from the upper 300 m of the water column in the northwestern Sargasso Sea, on cruises between 1991 and 2004. The region sampled spans the extent of deep winter mixing and the transition between the euphotic and the upper mesopelagic zones, where most carbon fixation and reoxidation occurs. A bioinformatic pipeline was developed to de-noise, normalize and align terminal restriction fragment length polymorphism (T-RFLP) data from three restriction enzymes and link T-RFLP peaks to microbial clades. Non-metric multidimensional scaling statistics resolved three microbial communities with distinctive composition during seasonal stratification: a surface community in the region of lowest nutrients, a deep chlorophyll maximum community and an upper mesopelagic community. A fourth microbial community was associated with annual spring blooms of eukaryotic phytoplankton that occur in the northwestern Sargasso Sea as a consequence of winter convective mixing that entrains nutrients to the surface. Many bacterial clades bloomed in seasonal patterns that shifted with the progression of stratification. These richly detailed patterns of community change suggest that highly specialized adaptations and interactions govern the success of microbial populations in the oligotrophic ocean.

Plate Margin Deformation and Active Tectonics Along the Northern Edge of the Yakutat Terrane in the Saint Elias Orogen, Alaska and Yukon, Canada

NASA Technical Reports Server (NTRS)

Bruhn, Ronald L.; Sauber, Jeanne; Cotton, Michele M.; Pavlis, Terry L.; Burgess, Evan; Ruppert, Natalia; Forster, Richard R.

2012-01-01

The northwest directed motion of the Pacific plate is accompanied by migration and collision of the Yakutat terrane into the cusp of southern Alaska. The nature and magnitude of accretion and translation on upper crustal faults and folds is poorly constrained, however, due to pervasive glaciation. In this study we used high-resolution topography, geodetic imaging, seismic, and geologic data to advance understanding of the transition from strike-slip motion on the Fairweather fault to plate margin deformation on the Bagley fault, which cuts through the upper plate of the collisional suture above the subduction megathrust. The Fairweather fault terminates by oblique-extensional splay faulting within a structural syntaxis, allowing rapid tectonic upwelling of rocks driven by thrust faulting and crustal contraction. Plate motion is partly transferred from the Fairweather to the Bagley fault, which extends 125 km farther west as a dextral shear zone that is partly reactivated by reverse faulting. The Bagley fault dips steeply through the upper plate to intersect the subduction megathrust at depth, forming a narrow fault-bounded crustal sliver in the obliquely convergent plate margin. Since . 20 Ma the Bagley fault has accommodated more than 50 km of dextral shearing and several kilometers of reverse motion along its southern flank during terrane accretion. The fault is considered capable of generating earthquakes because it is linked to faults that generated large historic earthquakes, suitably oriented for reactivation in the contemporary stress field, and locally marked by seismicity. The fault may generate earthquakes of Mw <= 7.5.

78 FR 40427 - Reorganization and Expansion of Foreign-Trade Zone 45 Under Alternative Site Framework, Portland...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-05

... new Site 9 would be categorized as magnet sites, and existing Site 7 would be categorized as a usage... for the zone, to a five-year ASF sunset provision for magnet sites that would terminate authority for...

76 FR 34204 - Reorganization and Expansion of Foreign-Trade Zone 153 Under Alternative Site Framework, San...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-13

... categorized as magnet sites, Sites 6 and 10 would be reduced in size, existing Site 14 would be categorized as...-purpose zone project, to a five-year ASF sunset provision for magnet sites that would terminate authority...

75 FR 33787 - Reorganization and Expansion of Foreign-Trade Zone 174 Under Alternative Site Framework, Tucson, AZ

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-15

... existing Sites 1 through 6 would be categorized as magnet sites, and the grantee proposes one initial usage... general-purpose zone project, to a five-year ASF sunset provision for magnet sites that would terminate...

Crustal extension and transform faulting in the southern Basin Range Province. [California, Arizona, and Nevada

NASA Technical Reports Server (NTRS)

Liggett, M. A. (Principal Investigator); Childs, J. F.

1974-01-01

The author has identified the following significant results. Field reconnaissance and study of geologic literature guided by analysis of ERTS-1 MSS imagery have led to a hypothesis of tectonic control of Miocene volcanism, plutonism, and related mineralization in part of the Basin Range Province of southern Nevada and northwestern Arizona. The easterly trending right-lateral Las Vegas Shear Zone separates two volcanic provinces believed to represent areas of major east-west crustal extension. One volcanic province is aligned along the Colorado River south of the eastern termination of the Las Vegas Shear Zone; the second province is located north of the western termination of the shear zone in southern Nye County, Nevada. Geochronologic, geophysical, and structural evidence suggests that the Las Vegas Shear Zone may have formed in response to crustal extension in the two volcanic provinces in a manner similar to the formation of a ridge-ridge transform fault, as recognized in ocean floor tectonics.

Fabric evolution across a discontinuity between lower and upper crustal domains from field, microscopic, and anisotropy of magnetic susceptibility studies in central eastern Eritrea, NE Africa

NASA Astrophysics Data System (ADS)

Ghebreab, W.; Kontny, A.; Greiling, R. O.

2007-06-01

In the Neoproterozoic East African Orogen (EAO) of Eritrea, lower to middle crustal high-grade metamorphic rocks are juxtaposed against low-grade upper crustal rocks along diffuse tectonic contact zones or discontinuities. In the central eastern part of Eritrea, such a tectonic zone is exposed as a low-angle shear zone separating two distinct high- and low-grade domains, the Ghedem and Bizen, respectively. Integrated field, microfabric, and anisotropy of magnetic susceptibility (AMS) studies show that this low-angle shear zone formed during late deformation, D2, with top-to-the-E/SE sense of motion. The hanging wall upper crustal volcanosedimentary schists are mainly paramagnetic and the footwall middle crustal mylonitized orthogneisses are mainly ferrimagnetic. Magnetic fabric studies revealed a good agreement between metamorphic/mylonitic and magnetic foliations (Kmin) and helped to explain fabric development in the shear zone. The magnetic lineations (Kmax) reflect stretching lineations where stretched mineral aggregates dominate fine-grained mylonitic matrices and intersection lineations where microstructural studies revealed two fabric elements. AMS directional plots indicate that the orientations of the magnetic lineation and of the pole to the magnetic foliation vary systematically across the shear zone. While Kmax axes form two broad maxima oriented approximately N-S and E-W, the Kmin axes change from subhorizontal, generally westward inclination in the west to moderate to steep inclination in the direction of tectonic movement to the east. Because there is a systematic change in inclination of Kmin for individual samples, all samples together form a fairly well defined cluster distribution. The distribution of Kmin in combination with the E-W scattered plot of the Kmax is in accordance with the E/SE flow of mylonites over exhumed Damas core complex in the late Neoproterozoic. During the Cenozoic, the Red Sea rift-related detachments exploited the late orogenic shear zone, indicating that the discontinuities between ductile middle and brittle upper crustal layers in the region are reactivated low-angle shear zones and possible sites of core complexes.

The locations and amounts of endogenous ions and elements in the cap and elongating zone of horizontally oriented roots of Zea mays L.: an electron-probe EDS study

NASA Technical Reports Server (NTRS)

Moore, R.; Cameron, I. L.; Hunter, K. E.; Olmos, D.; Smith, N. K.

1987-01-01

We used quantitative electron-probe energy-dispersive x-ray microanalysis to localize endogenous Na, Cl, K, P, S, Mg and Ca in cryofixed and freeze-dried cryosections of the cap (i.e. the putative site of graviperception) and elongating zone (i.e. site of gravicurvature) of horizontally oriented roots of Zea mays. Ca, Na, Cl, K and Mg accumulate along the lower side of caps of horizontally oriented roots. The most dramatic asymmetries of these ions occur in the apoplast, especially the mucilage. We could not detect any significant differences in the concentrations of these ions in the central cytoplasm of columella cells along the upper and lower sides of caps of horizontally-oriented roots. However, the increased amounts of Na, Cl, K and Mg in the longitudinal walls of columella cells along the lower side of the cap suggest that these ions may move down through the columella tissue of horizontally-oriented roots. Ca also accumulates (largely in the mucilage) along the lower side of the elongating zone of horizontally-oriented roots, while Na, P, Cl and K tend to accumulate along the upper side of the elongating zone. Of these ions, only K increases in concentration in the cytoplasm and longitudinal walls of cortical cells in the upper vs lower sides of the elongating zone. These results indicate that (1) gravity-induced asymmetries of ions differ significantly in the cap and elongating zone of graviresponding roots, (2) Ca accumulates along the lower side of the cap and elongating zone of graviresponding roots, (3) increased growth of the upper side of the elongating zone of horizontally-oriented roots correlates positively with increased amounts of K in the cytoplasm and longitudinal walls of cortical cells, and (4) the apoplast (especially the mucilage) may be an important component of the pathway via which ions move in graviresponding rots of Zea mays. These results are discussed relative to mechanisms for graviperception and gravicurvature of roots.

49 CFR 372.300 - Distances and population data.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...

49 CFR 372.300 - Distances and population data.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...

49 CFR 372.300 - Distances and population data.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...

49 CFR 372.300 - Distances and population data.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...

49 CFR 372.300 - Distances and population data.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...

An analysis of seismic hazard in the Upper Rhine Graben enlightened by the example of the New Madrid seismic zone.

NASA Astrophysics Data System (ADS)

Doubre, Cécile; Masson, Frédéric; Mazzotti, Stéphane; Meghraoui, Mustapha

2014-05-01

Seismic hazard in the "stable" continental regions and low-level deformation zones is one of the most difficult issues to address in Earth sciences. In these zones, instrumental and historical seismicity are not well known (sparse seismic networks, seismic cycle too long to be covered by the human history, episodic seismic activity) and many active structures remain poorly characterized or unknown. This is the case of the Upper Rhine Graben, the central segment of the European Cenozoic rift system (ECRIS) of Oligocene age, which extends from the North Sea through Germany and France to the Mediterranean coast over a distance of some 1100 km. Even if this region has already experienced some destructive earthquakes, its present-day seismicity is moderate and the deformation observed by geodesy is very small (below the current measurement accuracy). The strain rate does not exceed 10-10 and paleoseismic studies indicate an average return period of 2.5 to 3 103 ka for large earthquakes. The largest earthquake known for this zone is the 1356 Basel earthquake, with a magnitude generally estimated about 6.5 (Meghraoui et al., 2001) but recently re-evaluated between 6.7 and 7.1 (Fäh et al et al., 2009). A comparison of the Upper Rhine Graben with equivalent regions around the world could help improve our evaluation of seismic hazard of this region. This is the case of the New Madrid seismic zone, one of the best studied intraplate system in central USA, which experienced an M 7.0 - 7.5 earthquake in 1811-1812 and shares several characteristics with the Upper Rhine Graben, i.e. the general framework of inherited geological structures (reactivation of a failed rift / graben), seismicity patterns (spatial variability of small and large earthquakes), the null or low rate of deformation, and the location in a "stable" continental interior. Looking at the Upper Rhine Graben as an analogue of the New Madrid seismic zone, we can re-evaluate its seismic hazard and consider the possibility of an earthquake of magnitude 7 or greater.

Upper Neogene stratigraphy and tectonics of Death Valley - A review

USGS Publications Warehouse

Knott, J.R.; Sarna-Wojcicki, A. M.; Machette, M.N.; Klinger, R.E.

2005-01-01

New tephrochronologic, soil-stratigraphic and radiometric-dating studies over the last 10 years have generated a robust numerical stratigraphy for Upper Neogene sedimentary deposits throughout Death Valley. Critical to this improved stratigraphy are correlated or radiometrically-dated tephra beds and tuffs that range in age from > 3.58 Ma to < 1.1 ka. These tephra beds and tuffs establish relations among the Upper Pliocene to Middle Pleistocene sedimentary deposits at Furnace Creek basin, Nova basin, Ubehebe-Lake Rogers basin, Copper Canyon, Artists Drive, Kit Fox Hills, and Confidence Hills. New geologic formations have been described in the Confidence Hills and at Mormon Point. This new geochronology also establishes maximum and minimum ages for Quaternary alluvial fans and Lake Manly deposits. Facies associated with the tephra beds show that ???3.3 Ma the Furnace Creek basin was a northwest-southeast-trending lake flanked by alluvial fans. This paleolake extended from the Furnace Creek to Ubehebe. Based on the new stratigraphy, the Death Valley fault system can be divided into four main fault zones: the dextral, Quaternary-age Northern Death Valley fault zone; the dextral, pre-Quaternary Furnace Creek fault zone; the oblique-normal Black Mountains fault zone; and the dextral Southern Death Valley fault zone. Post -3.3 Ma geometric, structural, and kinematic changes in the Black Mountains and Towne Pass fault zones led to the break up of Furnace Creek basin and uplift of the Copper Canyon and Nova basins. Internal kinematics of northern Death Valley are interpreted as either rotation of blocks or normal slip along the northeast-southwest-trending Towne Pass and Tin Mountain fault zones within the Eastern California shear zone. ?? 2005 Elsevier B.V. All rights reserved.

Overview of the magnetic signatures of the Palaeoproterozoic Rustenburg Layered Suite, Bushveld Complex, South Africa

USGS Publications Warehouse

Cole, Janine; Finn, Carol A.; Webb, Susan J.

2013-01-01

Aeromagnetic data clearly delineate the mafic rocks of the economically significant Bushveld Igneous Complex. This is mainly due to the abundance of magnetite in the Upper Zone of the Rustenburg Layered Suite of the Bushveld, but strongly remanently magnetised rocks in the Main Zone also contribute significantly in places. In addition to delineating the extent of the magnetic rocks in the complex, the magnetic anomalies also provide information about the dip and depth of these units. The presence of varying degrees of remanent magnetisation in most of the magnetic lithologies of the Rustenburg Layered Suite complicates the interpretation of the data. The combination of available regional and high resolution airborne magnetic data with published palaeomagnetic data reveals characteristic magnetic signatures associated with the different magnetic lithologies in the Rustenburg Layered Suite. As expected, the ferrogabbros of the Upper Zone cause the highest amplitude magnetic anomalies, but in places subtle features within the Main Zone can also be detected. A marker with strong remanent magnetisation located in the Main Zone close to the contact with the Upper Zone is responsible for very high amplitude negative anomalies in the southern parts of both the eastern and western lobes of the Bushveld Complex. Prominent anomalies are not necessarily related to a specific lithology, but can result from the interaction between anomalies caused by differently magnetised bodies.The magnetic data provided substantial information at different levels of detail, ranging from contacts between zones, and layering within zones, to magnetite pipes dykes and faults that can have an impact on mine planning. Finally, simple modelling of the magnetic data supports the concept of continuous mafic rocks between the western and eastern lobes.

Consequences of Rift Propagation for Spreading in Thick Oceanic Crust in Iceland

NASA Astrophysics Data System (ADS)

Karson, J. A.

2015-12-01

Iceland has long been considered a natural laboratory for processes related to seafloor spreading, including propagating rifts, migrating transforms and rotating microplates. The thick, hot, weak crust and subaerial processes of Iceland result in variations on the themes developed along more typical parts of the global MOR system. Compared to most other parts of the MOR, Icelandic rift zones and transform faults are wider and more complex. Rift zones are defined by overlapping arrays of volcanic/tectonic spreading segments as much as 50 km wide. The most active rift zones propagate N and S away from the Iceland hot spot causing migration of transform faults. A trail of crust deformed by bookshelf faulting forms in their wakes. Dead or dying transform strands are truncated along pseudofaults that define propagation rates close to the full spreading rate of ~20 mm/yr. Pseudofaults are blurred by spreading across wide rift zones and laterally extensive subaerial lava flows. Propagation, with decreasing spreading toward the propagator tips causes rotation of crustal blocks on both sides of the active rift zones. The blocks deform internally by the widespread reactivation of spreading-related faults and zones of weakness along dike margins. The sense of slip on these rift-parallel strike-slip faults is inconsistent with transform-fault deformation. These various deformation features as well as subaxial subsidence that accommodate the thickening of the volcanic upper crustal units are probably confined to the brittle, seismogenic, upper 10 km of the crust. At least beneath the active rift zones, the upper crust is probably decoupled from hot, mechanically weak middle and lower gabbroic crust resulting in a broad plate boundary zone between the diverging lithosphere plates. Similar processes may occur at other types of propagating spreading centers and magmatic rifts.

Inter-Rater Agreement of Auscultation, Palpable Fremitus, and Ventilator Waveform Sawtooth Patterns Between Clinicians.

PubMed

Berry, Marc P; Martí, Joan-Daniel; Ntoumenopoulos, George

2016-10-01

Clinicians often use numerous bedside assessments for secretion retention in participants who are receiving invasive mechanical ventilation. This study aimed to evaluate inter-rater agreement between clinicians when using standard clinical assessments of secretion retention and whether differences in clinician experience influenced inter-rater agreement. Seventy-one mechanically ventilated participants were assessed by a research clinician and by one of 13 ICU clinicians. Each clinician conducted a standardized assessment of lung auscultation, palpation for chest-wall (rhonchal) fremitus, and ventilator inspiratory/expiratory flow-time waveforms for the sawtooth pattern. On the presence of breath sounds, agreement ranged from absolute to moderate in the upper zones and the lower zones, respectively. Kappa values for abnormal and adventitious lung sounds achieved moderate agreement in the upper zones, less than chance agreement to substantial agreement in the middle zones, and moderate agreement to almost perfect agreement in the lower zones. Moderate to almost perfect agreement was established for palpable fremitus in the upper zones, moderate to substantial agreement in the middle zones, and less than chance to moderate agreement in the lower zones. Inter-rater agreement on the presence of expiratory sawtooth pattern identification showed moderate agreement. The level of percentage agreement between the research and ICU clinicians for each respiratory assessment studied did not relate directly to level of clinical experience. Inter-rater agreement for all assessments showed variability between lung regions but maintained reasonable percentage agreement in mechanically ventilated participants. The level of percentage agreement achieved between clinicians did not directly relate to clinical experience for all respiratory assessments. Therefore, these respiratory assessments should not necessarily be viewed in isolation but interpreted within the context of a full clinical assessment. Copyright © 2016 by Daedalus Enterprises.

Biostratigraphy and event stratigraphy in Iran around the Permian Triassic Boundary (PTB): Implications for the causes of the PTB biotic crisis

NASA Astrophysics Data System (ADS)

Kozur, H. W.

2007-01-01

The conodont succession and stratigraphic events around the Permian-Triassic boundary (PTB) have been investigated in detail in the open sea deposits of Iran (Abadeh and Shahreza in central Iran, and Jolfa and Zal in northwestern Iran). This investigation produced a very detailed conodont zonation from the Clarkina nodosa Zone up to the Isarcicella isarcica Zone. All significant events have been accurately located and dated within this zonation, and the duration of most of these conodont zones has been calculated by cross-correlation with continental lake deposits that display obvious Milankovitch cyclicity. The unusually short duration of all conodont zones in the interval from the C. nodosa up to the Hindeodus parvus Zone indicates that there was persistent high ecological stress during this time interval. Most of the conodont zones can be accurately correlated with South China. In the interval from the C. hauschkei Zone to the H. parvus Zone, even correlation with the Arctic is possible. Within three thin stratigraphic intervals, the Changhsingian (Dorashamian) warm water conodont fauna of the C. subcarinata lineage is replaced by a cool water fauna with small H. typicalis, rare Merrillina sp., and cool water Clarkina that have very widely spaced denticles. The uppermost cool water fauna horizon comprises the lower C. zhangi Zone and can be accurately correlated with continental beds by recognition of a short reversed magnetozone below the long uppermost Permian-lowermost Triassic normal magnetozone. In Iran and Transcaucasia, this short reversed zone comprises the upper C. changxingensis- C. deflecta Zone and most of the C. zhangi Zone. Its top lies 50 cm below the top of the Paratirolites Limestone (s.s.) in the Dorasham 2 section, which is at the beginning of the upper quarter of the C. zhangi Zone. In the Germanic Basin, this short palaeomagnetic interval comprises the lower and the basal part of the upper Fulda Formation. On the Russian Platform, the Nedubrovo Formation belongs to this short reversed magnetic interval. In its upper part (corresponding to the top of the lower C. zhangi Zone, see above) there is a fallout of mafic tuffs from the Siberian Trap event that originated about 3000 km away in eruption centres in the Siberian Tungusska Basin. In the Germanic Basin and in Iran, this horizon contains volcanic microsphaerules. Thus, a direct correlation can be made between the immigration of a cool water fauna into the tropical realm and an exceptionally strong interval of explosive activity during the Siberian Trap volcanic episode. These faunal changes are the same as those found at the base of the Boundary Clay, suggesting that a short cooling event at this horizon also was due to intense volcanism. Additional influence by a bolide impact cannot be excluded. Most of the events in the interval from the C. nodosa up to the I. isarcica Zone (upper Changhsingian to middle Gangetian) in the Iranian sections can be also observed in other marine sections (e.g., in Meishan) and even in continental sections of the Germanic Basin. Of particular significance is the fact that, in the investigated Iranian sections, the PTB lies either in red sediments or in light grey sediments (as in Abadeh) that contain an ostracod fauna indicative of highly oxygenated bottom waters. Therefore, anoxia cannot be the reason for the PTB extinction event in this region, even though anoxia does cause locally or regionally elsewhere an overprint on the extinction event.

Geomorphic features off southern California as seen by GLORIA side-scan sonar system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, B.D.; Field, M.E.; Carlson, P.R.

1985-02-01

Approximately 165,000 km/sup 2/ of the sea floor off southern California was mapped during May 1984, as part of a USGS/IOS cooperative program to study the newly proclaimed Exclusive Economic Zone (EEZ) of the US Pacific margin. The area was insonified using the Geological Long-Range Inclined Asdic (GLORIA), a long-range side-scan sonar system. Images were corrected for water-column velocity anomalies, for along-track distortions caused by acoustic ray travel paths. A photomosaic of the overlapping sonographs has been compiled at a scale of 1:375,000. The basins of the inner California continental borderland are characterized by both sinuous channel and fan complexesmore » and by feathery acoustic patterns indicating active sediment transport. In contrast, outer borderland basins appear to be more sediment starved, exhibit large areas of sediment failure, and show significant structural influence. West of Patton Escarpment, the sonographs are dominated by acoustic patterns showing volcanic ridges and seamounts and by deposits of the Monterey and Arguello fans. Arguello fan, for example, exhibits multiple sinuous channels that have transported sediment 60 km south from the canyon mouth. These channels coalesce into a single 100-km long, westward-meandering channel that terminates in a 600-m deep box canyon. A zone of sediment failure is identifiable on the north levee of an upper fan channel. Tectonic trends associated with oceanic basement are highlighted by the terminus of the west-trending Murray Fracture Zone and by the prevailing northeast trend of volcanic ridge and seamount chains.« less

Lithostratigraphy, biostratigraphy and chemostratigraphy of Upper Cretaceous and Paleogene sediments from southern Tanzania: Tanzania Drilling Project Sites 27-35

NASA Astrophysics Data System (ADS)

Jimènez Berrocoso, Àlvaro; Huber, Brian T.; MacLeod, Kenneth G.; Petrizzo, Maria Rose; Lees, Jacqueline A.; Wendler, Ines; Coxall, Helen; Mweneinda, Amina K.; Falzoni, Francesca; Birch, Heather; Singano, Joyce M.; Haynes, Shannon; Cotton, Laura; Wendler, Jens; Bown, Paul R.; Robinson, Stuart A.; Gould, Jeremy

2012-07-01

The 2008 Tanzania Drilling Project (TDP) expedition recovered common planktonic foraminifera (PF), calcareous nannofossils (CN) and calcareous dinoflagellates with extraordinary shell preservation at multiple Cenomanian-Campanian sites that will be used for paleoclimatic, paleoceanographic, and biostratigraphic studies. New cores confirm the existence of a more expanded and continuous Upper Cretaceous sequence than had previously been documented in the Lindi and Kilwa regions of southeastern coastal Tanzania. This TDP expedition cored 684.02 m at eight Upper Cretaceous sites (TDP Sites 28-35) and a thin Paleocene section (TDP Site 27). TDP Sites 29, 30, 31 and 34 together span the lowermost Turonian to Coniacian (PF Whiteinella archaeocretacea to Dicarinella concavata Zones and CN Zones UC6a-9b), with TDP Site 31 being the most biostratigraphically complete Turonian section found during TDP drilling. A discontinuous section from the Santonian-upper Campanian (PF D. asymetrica to Radotruncana calcarata Zones and CN Zones UC12-16) was collectively recovered at TDP Sites 28, 32 and 35, while thin sequences of the lower Cenomanian (PF Thalmanninella globotruncanoides Zone and CN subzones UC3a-b) and middle Paleocene (Selandian; PF Zone P3a and CN Zone NP5) were cored in TDP Sites 33 and 27, respectively. Records of δ13Corg and δ13Ccarb from bulk sediments generated for all the Cretaceous sites show largely stable values through the sections. Only a few parallel δ13Corg and δ13Ccarb shifts have been found and they are interpreted to reflect local processes. The δ18Ocarb record, however, is consistent with Late Cretaceous cooling trends from the Turonian into the Campanian. Lithologies of these sites include thick intervals of claystones and siltstones with locally abundant, finely-laminated fabrics, irregular occurrences of thin sandstone layers, and sporadic bioclastic debris (e.g., inoceramids, ammonites). Minor lithologies represent much thinner units of up to medium-grained, massive sandstones. The %CaCO3 (∼5-40%) and %Corg (∼0.1-2%) are variable, with the highest %CaCO3 in the lower Campanian and the highest %Corg in the Turonian. Lithofacies analysis suggests that deposition of these sediments occurred in outer shelf-upper slope, a setting that agrees well with inferences from benthic foraminifera and calcareous dinoflagellates.

Geophysical characteristics of the hydrothermal systems of Kilauea volcano, Hawaii

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kauahikaua, J.

1993-08-01

Clues to the structure of Kilauea volcano can be obtained from spatial studies of gravity, magnetic, and seismic velocity variations. The rift zones and summit are underlain by dense, magnetic, and seismic velocity variations. The rift zones and summit are underlain by dense, magnetic, high P-wave-velocity rocks at depths of about 2 km less. The gravity and seismic velocity studies indicate that the rift structures are broad, extending farther to the north than to the south of the surface features. The magnetic data allow separation into a narrow, highly-magnetized, shallow zone and broad, flanking, magnetic lows. The patterns of gravity,more » magnetic variations, and seismicity document the southward migration of the upper east rift zone. Regional, hydrologic features of Kilauea can be determined from resistivity and self-potential studies. High-level groundwater exists beneath Kilauea summit to elevations of +800 m within a triangular area bounded by the west edge of the upper southwest rift zone, the east edge of the upper east rift zone, and the Koa'e fault system. High-level groundwater is present within the east rift zone beyond the triangular summit area. Self-potential mapping shows that areas of local heat produce local fluid circulation in the unconfined aquifer (water table). Shallow seismicity and surface deformation indicate that magma is intruding and that fractures are forming beneath the rift zones and summit area. Heat flows of 370--820 mW/m[sup 2] are calculated from deep wells within the lower east rift zone. The estimated heat input rate for Kilauea of 9 gigawatts (GW) is at least 25 times higher than the conductive heat loss as estimated from the heat flow in wells extrapolated over the area of the summit caldera and rift zones. 115 refs., 13 figs., 1 tab.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rudeen, David Keith; Weber, Paula D.; Lord, David L.

The U.S. Strategic Petroleum Reserve implemented the first stage of a leach plan in 2011-2012 to expand storage volume in the existing Bryan Mound 113 cavern from a starting volume of 7.4 million barrels (MMB) to its design volume of 11.2 MMB. The first stage was terminated several months earlier than expected in August, 2012, as the upper section of the leach zone expanded outward more quickly than design. The oil-brine interface was then re-positioned with the intent to resume leaching in the second stage configuration. This report evaluates the as-built configuration of the cavern at the end of themore » first stage, and recommends changes to the second stage plan in order to accommodate for the variance between the first stage plan and the as-built cavern. SANSMIC leach code simulations are presented and compared with sonar surveys in order to aid in the analysis and offer projections of likely outcomes from the revised plan for the second stage leach.« less

Assessment of body-powered upper limb prostheses by able-bodied subjects, using the Box and Blocks Test and the Nine-Hole Peg Test.

PubMed

Haverkate, Liz; Smit, Gerwin; Plettenburg, Dick H

2016-02-01

The functional performance of currently available body-powered prostheses is unknown. The goal of this study was to objectively assess and compare the functional performance of three commonly used body-powered upper limb terminal devices. Experimental trial. A total of 21 able-bodied subjects (n = 21, age = 22 ± 2) tested three different terminal devices: TRS voluntary closing Hook Grip 2S, Otto Bock voluntary opening hand and Hosmer Model 5XA hook, using a prosthesis simulator. All subjects used each terminal device nine times in two functional tests: the Nine-Hole Peg Test and the Box and Blocks Test. Significant differences were found between the different terminal devices and their scores on the Nine-Hole Peg Test and the Box and Blocks Test. The Hosmer hook scored best in both tests. The TRS Hook Grip 2S scored second best. The Otto Bock hand showed the lowest scores. This study is a first step in the comparison of functional performances of body-powered prostheses. The data can be used as a reference value, to assess the performance of a terminal device or an amputee. The measured scores enable the comparison of the performance of a prosthesis user and his or her terminal device relative to standard scores. © The International Society for Prosthetics and Orthotics 2014.

Time and order of eruption of first functional teeth in the upper jaw of post-larval life of Sicyopterus japonicus (Gobiidiae: Sicydiinae) during cranial metamorphosis at the time of river recruitment.

PubMed

Sahara, Noriyuki; Moriyama, Keita; Iida, Midori; Watanabe, Shun

2016-06-01

The present study was aimed at elucidating the time and order of eruption of first functional teeth in the upper jaw of post-larval life of Sicyopterus japonicus (S. japonicus) during cranial metamorphosis at the time of river recruitment. Fishes were caught at the post-larval stage at a river mouth and maintained for 7 days in a water tank. Each of 10 specimens was evaluated every day for 7 days by using microcomputed tomography, scanning electron microscopy, and light microscopy with peculiar attention to the development of the upper jaw teeth. Fishes caught at the river mouth were mostly transparent, with a rostral terminal mouth, and no teeth could be found in either the upper or lower jaw. At 2 days after collection, the mouth position changed from terminal to subterminal, resulting from a change in head shape. The initial eruption of first functional teeth was detected at the anterior two-thirds region of each upper jaw. These teeth erupted in adjacent positions, most had a tricuspid crown, and they represented miniature versions of adult teeth. At 5 days, the position of the mouth became further relocated from terminal rostral to ventral. The number of erupted teeth increased, followed by spreading of them anteriorly and posteriorly. At 7 days, they formed a single row of close-set tricuspid teeth along the entire length of each upper jaw. The present study demonstrated that even under laboratory conditions a rapid and drastic cranial metamorphosis took place within a week after the time of collection of post-larval S. japonicus from a river. The eruption of first functional teeth in the upper jaw of S. japonicus, which teeth are adapted to scraping algae off the substrate, was initially detected at 2 days after collection, and first functional dentition of the upper jaw was set up within 7 days after it. Copyright © 2016 Elsevier Ltd. All rights reserved.

49 CFR 372.221 - Twin Cities.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Twin Cities. 372.221 Section 372.221... ZONES, AND TERMINAL AREAS Commercial Zones § 372.221 Twin Cities. For the purpose of determining... following combinations of cities shall be considered as a single municipality: (a) Having a population equal...

49 CFR 372.221 - Twin Cities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Twin Cities. 372.221 Section 372.221... ZONES, AND TERMINAL AREAS Commercial Zones § 372.221 Twin Cities. For the purpose of determining... following combinations of cities shall be considered as a single municipality: (a) Having a population equal...

77 FR 73978 - Reorganization of Foreign-Trade Zone 93 Under Alternative Site Framework, Raleigh/Durham, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-12

..., 3, and 4 would be categorized as magnet sites, and FTZ 93's existing Site 2 would be categorized as... the zone, to a five-year ASF sunset provision for magnet sites that would terminate authority for Site...

77 FR 73009 - Reorganization of Foreign-Trade Zone 43 Under Alternative Site Framework, Battle Creek, MI

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

... Protection port of entry, FTZ 43's existing Site 1 would be categorized as a magnet site and existing Site 8... limit for the zone, to a five-year ASF sunset provision for magnet sites that would terminate authority...

Melorheostosis involving the cervical and upper thoracic spine: radiographic, CT, and MR imaging findings.

PubMed

Motimaya, A M; Meyers, S P

2006-01-01

Melorheostosis, an uncommon mesenchymal dysplasia, rarely affects the axial skeleton. We describe the imaging findings of melorheostosis involving the cervical and upper thoracic spine. Radiographs and CT showed unilateral well-marginated undulating zones of cortical hyperostosis involving multiple vertebrae that were contiguous with a coalescent ossified right paravertebral mass. MR imaging showed zones of signal intensity void on all pulse sequences without contrast enhancement. Conservative management was elected because of lack of interval clinical and imaging changes for 8 years.

The benthic macrofauna from the Lower Maastrichtian chalk of Kronsmoor (northern Germany, Saturn quarry): taxonomic outline and palaeoecologic implications

NASA Astrophysics Data System (ADS)

Engelke, Julia; Esser, Klaus J. K.; Linnert, Christian; Mutterlose, Jörg; Wilmsen, Markus

2016-12-01

The benthic macroinvertebrates of the Lower Maastrichtian chalk of Saturn quarry at Kronsmoor (northern Germany) have been studied taxonomically based on more than 1,000 specimens. Two successive benthic macrofossil assemblages were recognised: the lower interval in the upper part of the Kronsmoor Formation (Belemnella obtusa Zone) is characterized by low abundances of macroinvertebrates while the upper interval in the uppermost Kronsmoor and lowermost Hemmoor formations (lower to middle Belemnella sumensis Zone) shows a high macroinvertebrate abundance (eight times more than in the B. obtusa Zone) and a conspicuous dominance of brachiopods. The palaeoecological analysis of these two assemblages indicates the presence of eight different guilds, of which epifaunal suspension feeders (fixo-sessile and libero-sessile guilds), comprising approximately half of the trophic nucleus of the lower interval, increased to a dominant 86% in the upper interval, including a considerable proportion of rhynchonelliform brachiopods. It is tempting to relate this shift from the lower to the upper interval to an increase in nutrient supply and/or a shallowing of the depositional environment but further data including geochemical proxies are needed to fully understand the macrofossil distribution patterns in the Lower Maastrichtian of Kronsmoor.

Reconciling laboratory and observational models of mantle rheology in geodynamic modelling

NASA Astrophysics Data System (ADS)

King, Scott D.

2016-10-01

Experimental and geophysical observations constraining mantle rheology are reviewed with an emphasis on their impact on mantle geodynamic modelling. For olivine, the most studied and best-constrained mantle mineral, the tradeoffs associated with the uncertainties in the activation energy, activation volume, grain-size and water content allow the construction of upper mantle rheology models ranging from nearly uniform with depth to linearly increasing from the base of the lithosphere to the top of the transition zone. Radial rheology models derived from geophysical observations allow for either a weak upper mantle or a weak transition zone. Experimental constraints show that wadsleyite and ringwoodite are stronger than olivine at the top of the transition zone; however the uncertainty in the concentration of water in the transition zone precludes ruling out a weak transition zone. Both observational and experimental constraints allow for strong or weak slabs and the most promising constraints on slab rheology may come from comparing inferred slab geometry from seismic tomography with systematic studies of slab morphology from dynamic models. Experimental constraints on perovskite and ferropericlase strength are consistent with general feature of rheology models derived from geophysical observations and suggest that the increase in viscosity through the top of the upper mantle could be due to the increase in the strength of ferropericlase from 20-65 GPa. The decrease in viscosity in the bottom half of the lower mantle could be the result of approaching the melting temperature of perovskite. Both lines of research are consistent with a high-viscosity lithosphere, a low viscosity either in the upper mantle or transition zone, and high viscosity in the lower mantle, increasing through the upper half of the lower mantle and decreasing in the bottom half of the lower mantle, with a low viscosity above the core. Significant regions of the mantle, including high-stress regions of the lower mantle, may be in the dislocation creep (power-law) regime. Due to our limited knowledge of mantle grain size, the best hope to resolve the question of whether a region is in diffusion creep (Newtonian rheology) or dislocation or grain-boundary creep (power-law rheology), may be the presence of absence of seismic anisotropy, because there is no mechanism to rotate crystals in diffusion creep which would be necessary to develop anisotropy from lattice preferred orientation. While non-intuitive, the presence or absence of a weak region in the upper mantle has a profound effect on lower mantle flow. With an asthenosphere, the lower mantle organizes into a long-wavelength plan form with one or two (degree 1 or degree 2) large downwellings and updrafts, which may contain a cluster of plumes. The boundary between the long-wavelength lower mantle flow and upper region flow may be deeper, likely 800-1200 km, than the usually assumed base of the transition zone. There are competing hypotheses as to whether this change in flow pattern is caused by a change in rheology, composition, or phase.

Need to Identify Parameters of Concrete in the Weakest Zone of the Industrial Floor

NASA Astrophysics Data System (ADS)

Stawiski, Bohdan; Radzik, Łukasz

2017-10-01

The ways in which industrial floors are exploited leads to the requirement for the highest strength of their upper zone. Physical phenomena occurring during the compaction and hardening of the concrete cause different strength distributions. In the top zone of industrial floors, the strength is significantly lower (over a dozen MPa) than the strength in the bottom zone (several dozen MPa). Standard tests of control samples do not detect this fact. Processes for the application and finishing of embedded mineral-aggregate hardeners (dry shakes) can be regarded as uncontrolled. The effects of the use of dry shakes are not evaluated. In combination with the phenomenon of bleeding, they often fail by delamination. This paper presents the results of industrial floor testing. The ultrasonic pulse velocity method with dry point contact transducers was used. The results show how upper layer strength was reduced, and how dry shakes application affected the strength of the floor. The strength distribution in hardened concrete, which delaminated from the rest of the floor was presented as well. The extension of compulsory control tests of concrete samples was proposed. In the authors’ opinion, particular attention should be paid to 3 centimetres of the upper layer.

Middle to Late Devonian-Carboniferous collapse basins on the Finnmark Platform and in the southwesternmost Nordkapp basin, SW Barents Sea

NASA Astrophysics Data System (ADS)

Koehl, Jean-Baptiste P.; Bergh, Steffen G.; Henningsen, Tormod; Faleide, Jan Inge

2018-03-01

The SW Barents Sea margin experienced a pulse of extensional deformation in the Middle-Late Devonian through the Carboniferous, after the Caledonian Orogeny terminated. These events marked the initial stages of formation of major offshore basins such as the Hammerfest and Nordkapp basins. We mapped and analyzed three major fault complexes, (i) the Måsøy Fault Complex, (ii) the Rolvsøya fault, and (iii) the Troms-Finnmark Fault Complex. We discuss the formation of the Måsøy Fault Complex as a possible extensional splay of an overall NE-SW-trending, NW-dipping, basement-seated Caledonian shear zone, the Sørøya-Ingøya shear zone, which was partly inverted during the collapse of the Caledonides and accommodated top-NW normal displacement in Middle to Late Devonian-Carboniferous times. The Troms-Finnmark Fault Complex displays a zigzag-shaped pattern of NNE-SSW- and ENE-WSW-trending extensional faults before it terminates to the north as a WNW-ESE-trending, NE-dipping normal fault that separates the southwesternmost Nordkapp basin in the northeast from the western Finnmark Platform and the Gjesvær Low in the southwest. The WNW-ESE-trending, margin-oblique segment of the Troms-Finnmark Fault Complex is considered to represent the offshore prolongation of a major Neoproterozoic fault complex, the Trollfjorden-Komagelva Fault Zone, which is made of WNW-ESE-trending, subvertical faults that crop out on the island of Magerøya in NW Finnmark. Our results suggest that the Trollfjorden-Komagelva Fault Zone dies out to the northwest before reaching the western Finnmark Platform. We propose an alternative model for the origin of the WNW-ESE-trending segment of the Troms-Finnmark Fault Complex as a possible hard-linked, accommodation cross fault that developed along the Sørøy-Ingøya shear zone. This brittle fault decoupled the western Finnmark Platform from the southwesternmost Nordkapp basin and merged with the Måsøy Fault Complex in Carboniferous times. Seismic data over the Gjesvær Low and southwesternmost Nordkapp basin show that the low-gravity anomaly observed in these areas may result from the presence of Middle to Upper Devonian sedimentary units resembling those in Middle Devonian, spoon-shaped, late- to post-orogenic collapse basins in western and mid-Norway. We propose a model for the formation of the southwesternmost Nordkapp basin and its counterpart Devonian basin in the Gjesvær Low by exhumation of narrow, ENE-WSW- to NE-SW-trending basement ridges along a bowed portion of the Sørøya-Ingøya shear zone in the Middle to Late Devonian-early Carboniferous. Exhumation may have involved part of a large-scale metamorphic core complex that potentially included the Lofoten Ridge, the West Troms Basement Complex and the Norsel High. Finally, we argue that the Sørøya-Ingøya shear zone truncated and decapitated the Trollfjorden-Komagelva Fault Zone during the Caledonian Orogeny and that the western continuation of the Trollfjorden-Komagelva Fault Zone was mostly eroded and potentially partly preserved in basement highs in the SW Barents Sea.

Saltwater intrusion in the Floridan aquifer system near downtown Brunswick, Georgia, 1957–2015

USGS Publications Warehouse

Cherry, Gregory S.; Peck, Michael

2017-02-16

IntroductionThe Floridan aquifer system (FAS) consists of the Upper Floridan aquifer (UFA), an intervening confining unit of highly variable properties, and the Lower Floridan aquifer (LFA). The UFA and LFA are primarily composed of Paleocene- to Oligocene-age carbonate rocks that include, locally, Upper Cretaceous rocks. The FAS extends from coastal areas in southeastern South Carolina and continues southward and westward across the coastal plain of Georgia and Alabama, and underlies all of Florida. The thickness of the FAS varies from less than 100 feet (ft) in aquifer outcrop areas of South Carolina to about 1,700 ft near the city of Brunswick, Georgia.Locally, in southeastern Georgia and the Brunswick– Glynn County area, the UFA consists of an upper water-bearing zone (UWBZ) and a lower water-bearing zone (LWBZ), as identified by Wait and Gregg (1973), with aquifer test data indicating the upper zone has higher productivity than the lower zone. Near the city of Brunswick, the LFA is composed of two permeable zones: an early middle Eocene-age upper permeable zone (UPZ) and a highly permeable lower zone of limestone (LPZ) of Paleocene and Late Cretaceous age that includes a deeply buried, cavernous, saline water-bearing unit known as the Fernandina permeable zone. Maslia and Prowell (1990) inferred the presence of major northeast–southwest trending faults through the downtown Brunswick area based on structural analysis of geophysical data, northeastward elongation of the potentiometric surface of the UFA, and breaches in the local confining unit that influence the area of chloride contamination. Pronounced horizontal and vertical hydraulic head gradients, caused by pumping in the UFA, allow saline water from the FPZ to migrate upward into the UFA through this system of faults and conduits.Saltwater was first detected in the FAS in wells completed in the UFA near the southern part of the city of Brunswick in late 1957. By the 1970s, a plume of groundwater with high chloride concentrations had migrated northward toward two major industrial pumping centers, and since 1965, chloride concentrations have steadily increased in the northern part of the city. In 1978, data obtained from a 2,720-ft-deep test well (33H188) drilled south of the city showed water with a chloride concentration of 33,000 milligrams per liter (mg/L), suggesting the saltwater source was located below the UFA in the Fernandina permeable zone (FPZ) of the LFA.All U.S. Geological Survey (USGS) data collected for this study, including groundwater levels in wells and water-chemistry data, are available in the USGS National Water Information System.

Upper-Mantel Earthquakes in the Australia-Pacific Plate Boundary Zone and the Roots of the Alpine Fault

NASA Astrophysics Data System (ADS)

Boese, C. M.; Warren-Smith, E.; Townend, J.; Stern, T. A.; Lamb, S. H.

2016-12-01

Seismicity in the upper mantle in continental collision zones is relatively rare, but observed around the world. Temporary seismometer deployments have repeatedly detected mantle earthquakes at depths of 40-100 km within the Australia-Pacific plate boundary zone beneath the South Island of New Zealand. Here, the transpressive Alpine Fault constitutes the primary plate boundary structure linking subduction zones of opposite polarity farther north and south. The Southern Alps Microearthquake Borehole Array (SAMBA) has been operating continuously since November 2008 along a 50 km-long section of the central Alpine Fault, where the rate of uplift of the Southern Alps is highest. To date it has detected more than 40 small to moderate-sized mantle events (1≤ML≤3.9). The Central Otago Seismic Array (COSA) has been in operation since late 2012 and detected 15 upper mantle events along the sub-vertical southern Alpine Fault. Various mechanisms have been proposed to explain the occurrence of upper mantle seismicity in the South Island, including intra-continental subduction (Reyners 1987, Geology); high shear-strain gradients due to depressed geotherms and viscous deformation of mantle lithosphere (Kohler and Eberhart-Phillips 2003, BSSA); high strain rates resulting from plate bending (Boese et al. 2013, EPSL), and underthrusting of the Australian plate (Lamb et al. 2015, G3). Focal mechanism analysis reveals a variety of mechanisms for the upper mantle events but predominantly strike-slip and reverse faulting. In this study, we apply spectral analysis to better constrain source parameters for these mantle events. These results are interpreted in conjunction with new information about crustal structure and low-frequency earthquakes near the Moho and in light of existing velocity, attenuation and resistivity models.

40 CFR 205.54-1 - Low speed sound emission test procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... beyond the permissible end zone, unload the vehicle and/or increase the approach rpm in 100 rpm... rpm beyond the permissible end zone, unload the vehicle and/or increase the approach rpm in 100 rpm... example, temperature, humidity, and barometric pressure). (ii) Proper signal levels, terminat-ing...

77 FR 54891 - Reorganization of Foreign-Trade Zone 149 Under Alternative Site Framework Freeport, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-06

... 1, 3 and 10 would be categorized as magnet sites, and FTZ 149's Sites 2, 4, 5, 6, 7, 8, 9, 11 and 12... limit for the zone, and to a five-year ASF sunset provision for magnet sites that would terminate...

Structural evolution of the Sarandí del Yí Shear Zone, Uruguay: kinematics, deformation conditions and tectonic significance

NASA Astrophysics Data System (ADS)

Oriolo, S.; Oyhantçabal, P.; Heidelbach, F.; Wemmer, K.; Siegesmund, S.

2015-10-01

The Sarandí del Yí Shear Zone is a crustal-scale shear zone that separates the Piedra Alta Terrane from the Nico Pérez Terrane and the Dom Feliciano Belt in southern Uruguay. It represents the eastern margin of the Río de la Plata Craton and, consequently, one of the main structural features of the Precambrian basement of Western Gondwana. This shear zone first underwent dextral shearing under upper to middle amphibolite facies conditions, giving rise to the reactivation of pre-existing crustal fabrics in the easternmost Piedra Alta Terrane. Afterwards, pure-shear-dominated sinistral shearing with contemporaneous magmatism took place under lower amphibolite to upper greenschist facies conditions. The mylonites resulting from this event were then locally reactivated by a cataclastic deformation. This evolution points to strain localization under progressively retrograde conditions with time, indicating that the Sarandí del Yí Shear Zone represents an example of a thinning shear zone related to the collisional to post-collisional evolution of the Dom Feliciano Belt that occurred between the Meso- to Neoproterozoic (>600 Ma) and late Ediacaran-lower Cambrian times.

Trench curvature initiation: Upper plate strain pattern and volcanism Insights from the Lesser Antilles arc, St Barthélemy Island, FWI.

NASA Astrophysics Data System (ADS)

Philippon, M. M.; Legendre, L.; Münch, P.; Léticée, J. L.; Lebrun, J. F.; Maincent, G.; Mazabraud, Y.

2017-12-01

Upper plate deformation pattern reflect the mechanical behavior of subduction zones. In this study, we focus on the consequence of the entrance of a buoyant plateau within the Caribbean subduction zone during Eocene by studying the oldest cropping out rocks of the Lesser Antilles volcanic arc. Based on novel geochronological ages and available bio-stratigraphic data we show that St Barthélemy Island was built during three successive volcanic events over the Mid- Eocene to Oligo-Miocene time span. We show that magmatism is mainly Oligocene, not Eocene. Moreover, we demonstrate that tholeitic and calc-alkaline magmatism co-existed all along the arc activity. And ultimately we evidence a westward migration of the volcanism at the island scale. Furthermore, We demonstrate that during 21 Ma, the built of theses volcanoes, the stress regime evolves from pure to radial extension with a sub-horizontal σ3 showing N30° mean trend. To conclude, our novel results invalidate the chronological, geochemical and spatial evolution of the island arc magmatism formerly proposed in the early eighties. Indeed, arc magmatism in St Barthélemy was mainly related to the West-dipping Lesser Antilles subduction zone and not to the South-dipping Greater Antilles subduction and upper plate deformation evolution observed at local scale reflects large scale mechanical behavior of the Lesser Antilles subduction zone. A two steps restoration of the regional deformation shows that the switch from pure parallel to the trench extension to radial extension within the Caribbean upper plate reflects trench curvature that followed the entrance of the Bahamas bank in the Greater Antilles subduction zone and its collision.

76 FR 88 - Voluntary Termination of Foreign-Trade Subzone 102A, Ford Motor Corporation, Hazelwood, MO

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-03

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1728] Voluntary Termination of Foreign-Trade Subzone 102A, Ford Motor Corporation, Hazelwood, MO Pursuant to the authority granted in the... the Ford Motor Corporation plant in Hazelwood, Missouri (Board Order 252, 49 FR 19541, 5/8/84...

33 CFR 165.T0704 - Safety Zone: Savannah River, Savannah, Georgia.

Code of Federal Regulations, 2014 CFR

2014-07-01

...: Two hundred foot radius around Garden City Terminal, approximate position 32 degrees 8 minutes, N, 81... terminated by the Captain of the Port, Savannah, GA. (c) Regulation. In accordance with the general... the Captain of the Port, Savannah, GA to act on his behalf. A representative of the Captain of the...

33 CFR 165.T0704 - Safety Zone: Savannah River, Savannah, Georgia.

Code of Federal Regulations, 2012 CFR

2012-07-01

...: Two hundred foot radius around Garden City Terminal, approximate position 32 degrees 8 minutes, N, 81... terminated by the Captain of the Port, Savannah, GA. (c) Regulation. In accordance with the general... the Captain of the Port, Savannah, GA to act on his behalf. A representative of the Captain of the...

33 CFR 165.T0704 - Safety Zone: Savannah River, Savannah, Georgia.

Code of Federal Regulations, 2013 CFR

2013-07-01

...: Two hundred foot radius around Garden City Terminal, approximate position 32 degrees 8 minutes, N, 81... terminated by the Captain of the Port, Savannah, GA. (c) Regulation. In accordance with the general... the Captain of the Port, Savannah, GA to act on his behalf. A representative of the Captain of the...

33 CFR 165.T0704 - Safety Zone: Savannah River, Savannah, Georgia.

Code of Federal Regulations, 2011 CFR

2011-07-01

...: Two hundred foot radius around Garden City Terminal, approximate position 32 degrees 8 minutes, N, 81... terminated by the Captain of the Port, Savannah, GA. (c) Regulation. In accordance with the general... the Captain of the Port, Savannah, GA to act on his behalf. A representative of the Captain of the...

75 FR 56995 - Termination of Review of Sourcing Change, Foreign-Trade Subzone 61H, Baxter Healthcare of Puerto...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-17

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 44-2010] Termination of Review of Sourcing Change, Foreign-Trade Subzone 61H, Baxter Healthcare of Puerto Rico, (Inhalation Anesthetics... chemical ingredients at the manufacturing facility of Baxter Healthcare of Puerto Rico located in Guayama...

TOMOGRAPHY OF PLASMA FLOWS IN THE UPPER SOLAR CONVECTION ZONE USING TIME-DISTANCE INVERSION COMBINING RIDGE AND PHASE-SPEED FILTERING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Svanda, Michal, E-mail: michal@astronomie.cz; Astronomical Institute, Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, CZ-18000 Prague 8

2013-09-20

The consistency of time-distance inversions for horizontal components of the plasma flow on supergranular scales in the upper solar convection zone is checked by comparing the results derived using two k-{omega} filtering procedures-ridge filtering and phase-speed filtering-commonly used in time-distance helioseismology. I show that both approaches result in similar flow estimates when finite-frequency sensitivity kernels are used. I further demonstrate that the performance of the inversion improves (in terms of a simultaneously better averaging kernel and a lower noise level) when the two approaches are combined together in one inversion. Using the combined inversion, I invert for horizontal flows inmore » the upper 10 Mm of the solar convection zone. The flows connected with supergranulation seem to be coherent only for the top {approx}5 Mm; deeper down there is a hint of change of the convection scales toward structures larger than supergranules.« less

Retrogressive hydration of calc-silicate xenoliths in the eastern Bushveld complex: evidence for late magmatic fluid movement

NASA Astrophysics Data System (ADS)

Wallmach, T.; Hatton, C. J.; De Waal, S. A.; Gibson, R. L.

1995-11-01

Two calc-silicate xenoliths in the Upper Zone of the Bushveld complex contain mineral assemblages which permit delineation of the metamorphic path followed after incorporation of the xenoliths into the magma. Peak metamorphism in these xenoliths occurred at T=1100-1200°C and P <1.5 kbar. Retrograde metamorphism, probably coinciding with the late magmatic stage, is characterized by the breakdown of akermanite to monticellite and wollastonite at 700°C and the growth of vesuvianite from melilite. The latter implies that water-rich fluids (X CO 2 <0.2) were present and probably circulating through the cooling magmatic pile. In contrast, calc-silicate xenoliths within the lower zones of the Bushveld complex, namely in the Marginal and Critical Zones, also contain melilite, monticellite and additional periclase with only rare development of vesuvianite. This suggests that the Upper Zone cumulate pile was much 'wetter' in the late-magmatic stage than the earlier-formed Critical and Marginal Zone cumulate piles.

Sediment Flux of Particulate Organic Phosphorus in the Open Black Sea

NASA Astrophysics Data System (ADS)

Parkhomenko, A. V.; Kukushkin, A. S.

2018-03-01

The interannual variation of the monthly average (weighted average) concentrations of particulate organic phosphorus (PPOM) in the photosynthetic layer, oxycline, redox zone, and H2S zone in the open Black Sea is estimated based on long-term observation data. The suspension sedimentation rates from the studied layers are assessed using model calculations and published data. The annual variation of PPOM sediment fluxes from the photosynthetic layer, oxycline, redox zone, and upper H2S zone to the anaerobic zone of the sea and the correspondingly annual average values are estimated for the first time. A regular decrease in the PPOM annual average flux with depth in the upper active layer is demonstrated. A correlation between the annual average values of PPOM sediment flux from the photosynthetic layer and ascending phosphate flux to this layer is shown, which suggests their balance in the open sea. The results are discussed in terms of the phosphorus biogeochemical cycle and the concept of new and regenerative primary production in the open Black Sea.

A Tracer Study of Lebanese Upper Secondary School Students

ERIC Educational Resources Information Center

Vlaardingerbroek, Barend; Dallal, Kamel; Rizkallah, George; Rabah, Jihan

2007-01-01

This paper presents data arising from a tracer study of 90 terminating Beirut upper secondary school students. Nearly all the students intended to transit to university, about half of them to science and technology programmes, and subsequently did so. Median anticipated earnings upon graduation were realistic, but a lack of information or guidance…

Interaction of the Cyprus/Tethys Slab With the Mantle Transition Zone Beneath Anatolia

NASA Astrophysics Data System (ADS)

Thompson, D. A.; Rost, S.; Taylor, G.; Cornwell, D. G.

2017-12-01

The geodynamics of the eastern Mediterranean are dominated by northward motion of the Arabian/African continents and subduction of the oldest oceanic crust on the planet along the Aegean and Cyprean trenches. These slabs have previously been imaged using seismic tomography on a continental scale, but detailed information regarding their descent from upper to lower mantle and how they interact with the mantle transition zone have been severely lacking. The Dense Array for North Anatolia (DANA) was a 73 station passive seismic deployment active between 2012-2013 with the primary aim of imaging shallow structure beneath the North Anatolian Fault. However, we exploit the exceptional dataset recorded by DANA to characterise a region where the Cyprus Slab impinges upon the mantle transition zone beneath northern Turkey, providing arguably the most detailed view of a slab as it transits from the upper to lower mantle. We map varying depths and amplitudes of the transition zone seismic discontinuities (`410', `520' and `660') in 3D using over 1500 high quality receiver functions over an area of approximately 200km x 300km. The `410' is observed close to its predicted depth, but the `660' is depressed to >670 km across the entirety of the study region. This is consistent with an accumulation of cold subducted material at the base of the upper mantle, and the presence of a `520' discontinuity in the vicinity of the slab surface also suggests that the slab is present deep within the transition zone. Anomalous low velocity layers above and within the transition zone are constrained and may indicate hydration and ongoing mass/fluid flux between upper and lower mantle in the presence of subduction. The results of the study have implications not only for the regional geodynamics of Anatolia, but also for slab dynamics globally.

Slab geometry of the South American margin from joint inversion of body waves and surface waves

NASA Astrophysics Data System (ADS)

Porritt, R. W.; Ward, K. M.; Porter, R. C.; Portner, D. E.; Lynner, C.; Beck, S. L.; Zandt, G.

2016-12-01

The western margin of South America is a long subduction zone with a complex, highly three -dimensional geometry. The first order structure of the slab has previously been inferred from seismicity patterns and locations of volcanoes, but confirmation of the slab geometry by seismic imaging for the entire margin has been limited by either shallow, lithospheric scale models or broader, upper mantle images, often defined on a limited spatial footprint. Here, we present new teleseismic tomographic SV seismic models of the upper mantle from 10°S to 40°S along the South American subduction zone with resolution to a depth of 1000 km as inferred from checkerboard tests. In regions near the Peru Bolivia border (12°S to 18°S) and near central Chile and western Argentina (29.5°S to 33°S) we jointly invert the multi-band direct S and SKS relative delay times with Rayleigh wave phase velocities from ambient noise and teleseismic surface wave tomography. This self-consistent model provides information from the upper crust to below the mantle transition zone along the western margin in these two regions. This consistency allows tracing the slab from the South American coastline to the sub-transition zone upper mantle. From this model we image several features, but most notable is a significant eastward step near the southern edge of the margin (24°-30° S). West of this step, a large high shear velocity body is imaged in the base of and below the transition zone. We suggest this may be a stagnant slab, which is descending into the lower mantle now that it is no longer attached to the surface. This suggests a new component to the subduction history of western South America when an older slab lead the convergence before anchoring in the transition zone, breaking off from the surface, and being overtaken by the modern, actively subducting slab now located further east.

Zone heating for fluidized bed silane pyrolysis

NASA Technical Reports Server (NTRS)

Iya, Sridhar K. (Inventor)

1987-01-01

An improved heated fluidized bed reactor and method for the production of high purity polycrystalline silicon by silane pyrolysis wherein silicon seed particles are heated in an upper heating zone of the reactor and admixed with particles in a lower reaction zone, in which zone a silane-containing gas stream, having passed through a lower cooled gas distribution zone not conducive to silane pyrolysis, contacts the heated seed particles whereon the silane is heterogeneously reduced to silicon.

Mapping the influence of the deep Nazca slab on the geometry of the 660-km discontinuity beneath stable South America

NASA Astrophysics Data System (ADS)

Bianchi, M. B. D.; Assumpcao, M.; Julià, J.

2017-12-01

The fate of the deep Nazca subducted plate is poorly mapped under stable South America. Transition zone thickness and position is greatly dependent on mantle temperature and so is influenced by the colder Nazca plate position. We use a database of 35,000 LQT deconvolved receiver function traces to image the mantle transition zone and other upper mantle discontinuities under different terranes of stable South American continent. Data from the entire Brazilian Seismographic Network database, consisting of more than 80 broadband stations supplemented by 35 temporary stations deployed in west Brazil, Argentina, Paraguay, Bolivia and Uruguay were processed. Our results indicates that upper mantle velocities are faster than average under stable cratons and that most of the discontinuities are positioned with small variations in respect to nominal depths, except in places were the Nazca plate interacts with the transition zone. Under the Chaco-Pantanal basin the Nazca plate appears to be trapped in the transition zone for more than 1000 km with variations of up to 30 km in 660 km discontinuity topography under this region consistent with global tomographic models. Additional results obtained from SS precursor analysis of South Sandwich Islands teleseismic events recorded at USArray stations indicates that variations of transition zones thickness occur where the Nazca plate interacts with the upper mantle discontinuities in the northern part of Stable South American continent.

Mantle transition zone structure beneath the Canadian Shield

NASA Astrophysics Data System (ADS)

Thompson, D. A.; Helffrich, G. R.; Bastow, I. D.; Kendall, J. M.; Wookey, J.; Eaton, D. W.; Snyder, D. B.

2010-12-01

The Canadian Shield is underlain by one of the deepest and most laterally extensive continental roots on the planet. Seismological constraints on the mantle structure beneath the region are presently lacking due to the paucity of stations in this remote area. Presented here is a receiver function study on transition zone structure using data from recently deployed seismic networks from the Hudson Bay region. High resolution images based on high signal-to-noise ratio data show clear arrivals from the 410 km and 660 km discontinuities, revealing remarkably little variation in transition zone structure. Transition zone thickness is close to the global average (averaging 245 km across the study area), and any deviations in Pds arrival time from reference Earth models can be readily explained by upper-mantle velocity structure. The 520 km discontinuity is not a ubiquitous feature, and is only weakly observed in localised areas. These results imply that the Laurentian root is likely confined to the upper-mantle and if any mantle downwelling exists, possibly explaining the existence of Hudson Bay, it is also confined to the upper 400 km. Any thermal perturbations at transition zone depths associated with the existence of the root, whether they be cold downwellings or elevated temperatures due to the insulating effect of the root, are thus either non-existent or below the resolution of the study.

Fault evolution in the Potiguar rift termination, equatorial margin of Brazil

NASA Astrophysics Data System (ADS)

de Castro, D. L.; Bezerra, F. H. R.

2015-02-01

The transform shearing between South American and African plates in the Cretaceous generated a series of sedimentary basins on both plate margins. In this study, we use gravity, aeromagnetic, and resistivity surveys to identify architecture of fault systems and to analyze the evolution of the eastern equatorial margin of Brazil. Our study area is the southern onshore termination of the Potiguar rift, which is an aborted NE-trending rift arm developed during the breakup of Pangea. The basin is located along the NNE margin of South America that faces the main transform zone that separates the North and the South Atlantic. The Potiguar rift is a Neocomian structure located at the intersection of the equatorial and western South Atlantic and is composed of a series of NE-trending horsts and grabens. This study reveals new grabens in the Potiguar rift and indicates that stretching in the southern rift termination created a WNW-trending, 10 km wide, and ~ 40 km long right-lateral strike-slip fault zone. This zone encompasses at least eight depocenters, which are bounded by a left-stepping, en echelon system of NW-SE- to NS-striking normal faults. These depocenters form grabens up to 1200 m deep with a rhomb-shaped geometry, which are filled with rift sedimentary units and capped by postrift sedimentary sequences. The evolution of the rift termination is consistent with the right-lateral shearing of the equatorial margin in the Cretaceous and occurs not only at the rift termination but also as isolated structures away from the main rift. This study indicates that the strike-slip shearing between two plates propagated to the interior of one of these plates, where faults with similar orientation, kinematics, geometry, and timing of the major transform are observed. These faults also influence rift geometry.

Physical stratigraphy, paleontology, and magnetostratigraphy of the USGS-Santee Coastal Reserve core (CHN-803), Charleston County, South Carolina

USGS Publications Warehouse

Edwards, Lucy E.; Gohn, G.S.; ,; Prowell, D.C.; Bybell, L.M.; Bardot, L.P.; Firth, J.V.; Huber, B.T.; Frederiksen, N.O.; MacLeod, K.G.

1999-01-01

The Santee Coastal Reserve core, a 545-ft-deep corehole in northeastern Charleston County, South Carolina, recovered sediments of Late Cretaceous, Paleocene, Eocene, and Quaternary age. The deepest sediments, the Donoho Creek Formation (545-475.7 ft), consist of 69.3 ft of muddy calcareous sand of marine origin. This formation is placed within the upper Campanian calcareous nannofossil Subzone CC 22c. The overlying Peedee Formation (475.7-367.1 ft) in the core consists of 108.6 ft of silty clay of marine origin. It is placed in upper Maastrichtian calcareous nannofossil Subzones CC 25b, CC 26a, and CC 26b. Combined fossil and paleomagnetic information indicates nearly continuous deposition. Foraminifers indicate an outer neritic paleobathymetric setting. The Rhems Formation sensu stricto (367.1-267.3 ft) consists of 99.8 ft of silty clay, muddy sand, and minor calcite-cemented, shelly sand of marine origin. It is apparently the product of rapid sediment accumulation during a short period of time in the early Paleocene (calcareous nannofossil Zone NP 1). The upper part of the Rhems Formation sensu Bybell and others (1998) (267.3-237.4 ft) consists of 29.9 ft of calcite-cemented muddy sand and burrowed fine sand of marine origin. It is placed in calcareous nannofossil Zone NP 4 and, because it shows normal polarity, likely represents the upper part of the lower Paleocene. This unit may be correlative with the lower part of the Lower Bridge Member of the Williamsburg Formation in its type area. The Lower Bridge Member of the Williamsburg Formation (237.4-125.0 ft) has an unconformable contact at 205.0 ft that divides the member into lower muddy sand beds and upper calcareous clay beds. Both are placed in the upper Paleocene calcareous nannofossil Zone NP 5. The Chicora Member of the Williamsburg Formation (125-51.5 ft) consists of 73.5 ft of muddy, shelly sand of marine origin. It is poorly dated but includes late Paleocene nannofossils (Zones NP 5 and NP 6). A mollusk-bryozoan limestone (51.5-42.0 ft) above the Chicora Member of the Williamsburg yields early Eocene calcareous nannofossils representing both Zone NP 9/10 and Zone NP 12, together with pollen and dinocysts that are younger. Sediments of middle and late Eocene, Oligocene, Miocene, and Pliocene ages were not recovered in the Santee Coastal Reserve core. The upper 42.0 ft of sediments represent Quaternary deposits and are included in the Wando Formation (42.0-28.0 ft) and the informal Silver Bluff beds (28.0-0 ft).

Upper Cretaceous subsurface stratigraphy and structure of coastal Georgia and South Carolina

USGS Publications Warehouse

Valentine, Page C.

1982-01-01

Upper Cretaceous subsurface stratigraphy and structure of coastal Georgia and South Carolina is based on the study of 24 wells along two transects, one extending across the seaward-dipping sedimentary basin termed the 'Southeast Georgia Embayment' northeastward to the crest of the Cape Fear Arch, and the other alined east-west, parallel to the basin axis and including the COST GE-l well on the Outer Continental Shelf. A new biostratigraphic analysis, using calcareous nannofossils, of the Fripp Island, S.C., well and reinterpretations of the Clubhouse Crossroads corehole 1, South Carolina, and other wells in South Carolina, Georgia, and northernmost Florida have made possible the comparison and reevaluation of stratigraphic interpretations of the region made by G. S. Gohn and others in 1978 and 1980 and by P. M. Brown and others in 1979. The present study indicates that within the Upper Cretaceous section the stratigraphic units formerly assigned a Cenomanian (Eaglefordian and Woodbinian) age are Coniacian (Austinian) and Turonian (Eaglefordian) in age. A previously described hiatus encompassing Coniacian and Turonian time is not present. More likely, a hiatus is probably present in the upper Turonian, and major gaps in the record are present within the Cenomanian and between the Upper Cretaceous and the pre-Cretaceous basement. After an erosional episode in Cenomanian time that affected the section beneath eastern Georgia and South Carolina, Upper Cretaceous marine clastic and carbonate rocks were deposited on a regionally subsiding margin that extended to the present Blake Escarpment. In contrast, during Cenozoic time, especially in the Eocene, subsidence and sedimentation rates were uneven across the margin. A thick progradational sequence of carbonate rocks accumulated in the Southeast Georgia Embayment and also built the present Continental Shelf, whereas farther offshore a much thinner layer of sediments was deposited on the Blake Plateau. There is no general agreement on the exact placement of the Cenomanian-Turonian boundary in Europe or the United States Western Interior, and the widespread Sciponoceras gracile ammonite zone represents an interval of equivocal age between accepted Cenomanian and Turonian strata. The extinction of the foraminifer genus Rotalipora took place within the Sciporwceras gracile zone; it is used here to identify the Cenomanian-Turonian boundary. Pollen zone IV (Complexiopollis-Atlantopollis assemblage zone) is an important and widespread biostratigraphic unit characterized by a distinctive spore and pollen flora. It is consistently associated with lower Turonian calcareous nannofossils on the Atlantic continental margin; these nannofossil assemblages are also present in pollen zone IV, in strata that encompass the Sciponoceras gracile zone and the lower part of the Mytiloides labiatus zone in the Gulf Coastal Plain at Dallas, Tex.

Extensional deformation of the Guadalquivir Basin: rate of WSW-ward tectonic displacement from Upper Tortonian sedimentary rocks

NASA Astrophysics Data System (ADS)

Roldán, Francisco J.; Azañón, Jose Miguel; Rodríguez-Fernández, Jose; María Mateos, Rosa

2016-04-01

The Guadalquivir Basin (Upper Tortonian-Quaternary sedimentary infilling) has been considered the foreland basin of the Betic Orogen built up during its collision with the Sudiberian margin. The basin is currently restricted to its westernmost sector, in the Cadiz Gulf, because the Neogene-Quaternary uplift of the Betic Cordillera has produced the emersion of their central and eastern parts. The upper Tortonian chronostratigraphic unit is the oldest one and it was indistinctly deposited on the South Iberian paleomargin and the External units from the Betic Cordillera. However, these rocks are undeformed on the Sudiberian paleomargin while they are deeply affected by brittle deformation on the External Betic Zone. Outcrops of Upper Tortonian sedimentary rocks on External Betic Zone are severely fragmented showing allocthonous characters with regard to those located on the Sudiberian paleomargin. This post- Upper Tortonian deformation is not well known in the External Zones of the Cordillera where the most prominent feature is the ubiquity of a highly deformed tecto-sedimentary unit outcropping at the basement of the Guadalquivir sedimentary infilling. This tecto-sedimentary unit belongs to the Mass Wasting Extensional Complex (Rodríguez-Fernández, 2014) formed during the collision and westward migration of the Internal Zone of the Betic Cordillera (15-8,5 Ma). In the present work, we show an ensemble of tectonic, geophysical and cartographic data in order to characterize the post-Upper Tortonian deformation. For this, seismic reflection profiles have been interpreted with the help of hidrocarbon boreholes to define the thickness of the Upper Tortonian sedimentary sequence. All these data provide an estimation of the geometrical and kinematic characteristics of the extensional faults, direction of movement and rate of displacement of these rocks during Messinian/Pliocene times. References Rodríguez-Fernández, J., Roldan, F. J., J.M. Azañón y Garcia-Cortes, A. 2013. EL colapso gravitacional del frente orogénico alpino en el Dominio Subbético durante el Mioceno medio-superior: El Complejo Extensional Subbético. Boletín Geológico y Minero, 124 (3): 477-504

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING NORTHEAST TOWARD ...

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

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING NORTHEAST TOWARD THE REAR OF THE STRUCTURE. THE WHEELS AT THE TOP OF THE TRAM BUCKETS RODE OFF THE STATIONARY CABLES ONTO THE TRACK SUPPORTED BY THE "C" IRONS SUSPENDED FROM THE TOP TIMBERS, CLEARLY SEEN AT THE TOP OF THE FRAME. THE ANCHOR POINTS FOR THE TWO STATIONARY CABLES ARE AT BOTTOM CENTER, JUST BELOW THE CABLE WHEEL. THE MAIN CABLE WHEEL IS IN THE DISTANCE AT CENTER LEFT. THE ORE CHUTES COMING FROM THE ORE BIN ARE AT LEFT CENTER EDGE. TRAM BUCKETS WERE CHARGED HERE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

Static stress change from the 8 October, 2005 M = 7.6 Kashmir earthquake

USGS Publications Warehouse

Parsons, T.; Yeats, R.S.; Yagi, Y.; Hussain, A.

2006-01-01

We calculated static stress changes from the devastating M = 7.6 earthquake that shook Kashmir on 8 October, 2005. We mapped Coulomb stress change on target fault planes oriented by assuming a regional compressional stress regime with greatest principal stress directed orthogonally to the mainshock strike. We tested calculation sensitivity by varying assumed stress orientations, target-fault friction, and depth. Our results showed no impact on the active Salt Range thrust southwest of the rupture. Active faults north of the Main Boundary thrust near Peshawar fall in a calculated stress-decreased zone, as does the Raikot fault zone to the northeast. We calculated increased stress near the rupture where most aftershocks occurred. The greatest increase to seismic hazard is in the Indus-Kohistan seismic zone near the Indus River northwest of the rupture termination, and southeast of the rupture termination near the Kashmir basin.

Tertiary diachronic extrusion and deformation of western Indochina: Structural and 40Ar/39Ar evidence from NW Thailand

NASA Astrophysics Data System (ADS)

Lacassin, Robin; Maluski, Henri; Leloup, P. Hervé; Tapponnier, Paul; Hinthong, Chaiyan; Siribhakdi, Kanchit; Chuaviroj, Saengathit; Charoenravat, Adul

1997-05-01

The Wang Chao and Three Pagodas fault zones cut the western part of the Indochina block and run parallel to the Red River Fault. Evidence of intense ductile left-lateral shear is found in the Lansang gneisses, which form a 5 km wide elongated core along the Wang Chao fault zone. Dating by 40Ar/39Ar shows that such deformation probably terminated around 30.5 Ma. The Wang Chao and Three Pagodas faults offset the north striking lower Mesozoic metamorphic and magmatic belt of northern Thailand. 40Ar/39Ar results suggest that this belt suffered rapid cooling in the Tertiary, probably around 23 Ma. These results imply that the extrusion of the southwestern part of Indochina occurred in the upper Eocene-lower Oligocene. It probably induced rifting in some basins of the Gulf of Thailand and in the Malay and Mekong basins. In the Oligo-Miocene, the continuing penetration of India into Asia culminated with the extrusion of all of Indochina along the Ailao Shan-Red River fault. This occurred concurrently with the onset of E-W extension more to the south. Plotting in a geographical reference frame the diachronic time spans of movement on left-lateral faults east and southeast of Tibet implies that the northward movement of the Indian indenter successively initiated new strike-slip faults located farther and farther north along its path.

Collagen XII and XIV, new partners of cartilage oligomeric matrix protein in the skin extracellular matrix suprastructure.

PubMed

Agarwal, Pallavi; Zwolanek, Daniela; Keene, Douglas R; Schulz, Jan-Niklas; Blumbach, Katrin; Heinegård, Dick; Zaucke, Frank; Paulsson, Mats; Krieg, Thomas; Koch, Manuel; Eckes, Beate

2012-06-29

The tensile and scaffolding properties of skin rely on the complex extracellular matrix (ECM) that surrounds cells, vasculature, nerves, and adnexus structures and supports the epidermis. In the skin, collagen I fibrils are the major structural component of the dermal ECM, decorated by proteoglycans and by fibril-associated collagens with interrupted triple helices such as collagens XII and XIV. Here we show that the cartilage oligomeric matrix protein (COMP), an abundant component of cartilage ECM, is expressed in healthy human skin. COMP expression is detected in the dermal compartment of skin and in cultured fibroblasts, whereas epidermis and HaCaT cells are negative. In addition to binding collagen I, COMP binds to collagens XII and XIV via their C-terminal collagenous domains. All three proteins codistribute in a characteristic narrow zone in the superficial papillary dermis of healthy human skin. Ultrastructural analysis by immunogold labeling confirmed colocalization and further revealed the presence of COMP along with collagens XII and XIV in anchoring plaques. On the basis of these observations, we postulate that COMP functions as an adapter protein in human skin, similar to its function in cartilage ECM, by organizing collagen I fibrils into a suprastructure, mainly in the vicinity of anchoring plaques that stabilize the cohesion between the upper dermis and the basement membrane zone.

Collagen XII and XIV, New Partners of Cartilage Oligomeric Matrix Protein in the Skin Extracellular Matrix Suprastructure*

PubMed Central

Agarwal, Pallavi; Zwolanek, Daniela; Keene, Douglas R.; Schulz, Jan-Niklas; Blumbach, Katrin; Heinegård, Dick; Zaucke, Frank; Paulsson, Mats; Krieg, Thomas; Koch, Manuel; Eckes, Beate

2012-01-01

The tensile and scaffolding properties of skin rely on the complex extracellular matrix (ECM) that surrounds cells, vasculature, nerves, and adnexus structures and supports the epidermis. In the skin, collagen I fibrils are the major structural component of the dermal ECM, decorated by proteoglycans and by fibril-associated collagens with interrupted triple helices such as collagens XII and XIV. Here we show that the cartilage oligomeric matrix protein (COMP), an abundant component of cartilage ECM, is expressed in healthy human skin. COMP expression is detected in the dermal compartment of skin and in cultured fibroblasts, whereas epidermis and HaCaT cells are negative. In addition to binding collagen I, COMP binds to collagens XII and XIV via their C-terminal collagenous domains. All three proteins codistribute in a characteristic narrow zone in the superficial papillary dermis of healthy human skin. Ultrastructural analysis by immunogold labeling confirmed colocalization and further revealed the presence of COMP along with collagens XII and XIV in anchoring plaques. On the basis of these observations, we postulate that COMP functions as an adapter protein in human skin, similar to its function in cartilage ECM, by organizing collagen I fibrils into a suprastructure, mainly in the vicinity of anchoring plaques that stabilize the cohesion between the upper dermis and the basement membrane zone. PMID:22573329

Gasification of black liquor

DOEpatents

Kohl, A.L.

1987-07-28

A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediately above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone. 2 figs.

Gasification of black liquor

DOEpatents

Kohl, Arthur L.

1987-07-28

A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediatley above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone.

Forearc deformation and great subduction earthquakes: implications for cascadia offshore earthquake potential.

PubMed

McCaffrey, R; Goldfinger, C

1995-02-10

The maximum size of thrust earthquakes at the world's subduction zones appears to be limited by anelastic deformation of the overriding plate. Anelastic strain in weak forearcs and roughness of the plate interface produced by faults cutting the forearc may limit the size of thrust earthquakes by inhibiting the buildup of elastic strain energy or slip propagation or both. Recently discovered active strike-slip faults in the submarine forearc of the Cascadia subduction zone show that the upper plate there deforms rapidly in response to arc-parallel shear. Thus, Cascadia, as a result of its weak, deforming upper plate, may be the type of subduction zone at which great (moment magnitude approximately 9) thrust earthquakes do not occur.

How Many Convective Zones Are There in the Atmosphere of Venus?

NASA Astrophysics Data System (ADS)

Moroz, V. I.; Rodin, A. V.

2002-11-01

The qualitative characteristics of the vertical structure of the atmospheres of Venus and the Earth essentially differ. For instance, there are at least two, instead of one, zones with normal (thermal) convection on Venus. The first one is near the surface (a boundary layer); the second is at the altitudes of the lower part of the main cloud layer between 49 and 55 km. Contrary to the hypotheses proposed by Izakov (2001, 2002), the upper convective zone prevents energy transfer from the upper clouds to the subcloud atmosphere by ``anomalous turbulent heat conductivity.'' It is possible, however, that the anomalous turbulent heat conductivity takes part in the redistribution of the heat fluxes within the lower (subcloud) atmosphere.

Widespread gas hydrate instability on the upper U.S. Beaufort margin

NASA Astrophysics Data System (ADS)

Phrampus, Benjamin J.; Hornbach, Matthew J.; Ruppel, Carolyn D.; Hart, Patrick E.

2014-12-01

The most climate-sensitive methane hydrate deposits occur on upper continental slopes at depths close to the minimum pressure and maximum temperature for gas hydrate stability. At these water depths, small perturbations in intermediate ocean water temperatures can lead to gas hydrate dissociation. The Arctic Ocean has experienced more dramatic warming than lower latitudes, but observational data have not been used to study the interplay between upper slope gas hydrates and warming ocean waters. Here we use (a) legacy seismic data that constrain upper slope gas hydrate distributions on the U.S. Beaufort Sea margin, (b) Alaskan North Slope borehole data and offshore thermal gradients determined from gas hydrate stability zone thickness to infer regional heat flow, and (c) 1088 direct measurements to characterize multidecadal intermediate ocean warming in the U.S. Beaufort Sea. Combining these data with a three-dimensional thermal model shows that the observed gas hydrate stability zone is too deep by 100 to 250 m. The disparity can be partially attributed to several processes, but the most important is the reequilibration (thinning) of gas hydrates in response to significant (~0.5°C at 2σ certainty) warming of intermediate ocean temperatures over 39 years in a depth range that brackets the upper slope extent of the gas hydrate stability zone. Even in the absence of additional ocean warming, 0.44 to 2.2 Gt of methane could be released from reequilibrating gas hydrates into the sediments underlying an area of ~5-7.5 × 103 km2 on the U.S. Beaufort Sea upper slope during the next century.

33 CFR 165.1156 - Safety Zone; Offshore Marine Terminal, El Segundo, CA.

Code of Federal Regulations, 2010 CFR

2010-07-01

... area of the safety zone may contact the Captain of the Port at telephone number 1-800-221-8724 or on... OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Eleventh Coast Guard District...

78 FR 23515 - Regulated Navigation Areas, Security Zones: Dignitary Arrival/Departure and United Nations...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-19

... security zones as RNAs. The Marine Air Terminal, United Nations, and United Nations West Channel Closure... United Nations General Assembly RNA Regulated Navigation Area UN United Nations A. Public Participation... comment, it will be considered as having been received by the Coast Guard when it is received at the...

Managing the visual effects of outer continental shelf and other petroleum-related coastal development

Treesearch

Philip A. Marcus; Ethan T. Smith

1979-01-01

Five petroleum-related facilities often sited in the coastal zone during development of Outer Continental oil and gas can change the visual appearance of coastal areas. These facilities are service bases, platform fabrication yards, marine terminals and associated storage facilities, oil and gas processing facilities, and liquified natural gas terminals. Examples of...

76 FR 72675 - Voluntary Termination of Foreign-Trade Subzone 90A Smith Corona Corporation, Cortland County, New...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1799] Voluntary Termination of Foreign-Trade Subzone 90A Smith Corona Corporation, Cortland County, New York Pursuant to the authority granted... Smith Corona Corporation plant in Cortland County, New York (Board Order 300, 50 FR 15469, 04/18/85...

76 FR 80886 - Voluntary Termination of Foreign-Trade Subzone 84S Academy Sports and Outdoors, Katy and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-27

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1802] Voluntary Termination of Foreign-Trade Subzone 84S Academy Sports and Outdoors, Katy and Brookshire, TX Pursuant to the authority granted... at the Academy Sports and Outdoors facilities in Katy and Brookshire, Texas (Board Order 1511, 72 FR...

77 FR 38271 - Voluntary Termination of Foreign-Trade Subzone 33B Verosol USA, Inc. Kennedy Township, Allegheny...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-27

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1829] Voluntary Termination of Foreign-Trade Subzone 33B Verosol USA, Inc. Kennedy Township, Allegheny County, PA Pursuant to the authority... the establishment of Foreign-Trade Subzone 33B at the Verosol USA, Inc., plant in Kennedy Township...

Seismic evidence for water transport out of the mantle transition zone beneath the European Alps

NASA Astrophysics Data System (ADS)

Liu, Zhen; Park, Jeffrey; Karato, Shun-ichiro

2018-01-01

The mantle transition zone has been considered a major water reservoir in the deep Earth. Mass transfer across the transition-zone boundaries may transport water-rich minerals from the transition zone into the water-poor upper or lower mantle. Water release in the mantle surrounding the transition zone could cause dehydration melting and produce seismic low-velocity anomalies if some conditions are met. Therefore, seismic observations of low-velocity layers surrounding the transition zone could provide clues of water circulation at mid-mantle depths. Below the Alpine orogen, a depressed 660-km discontinuity has been imaged clearly using seismic tomography and receiver functions, suggesting downwellings of materials from the transition zone. Multitaper-correlation receiver functions show prominent ∼0.5-1.5% velocity reductions at ∼750-800-km depths, possibly caused by partial melting in the upper part of lower mantle. The gap between the depressed 660-km discontinuity and the low-velocity layers is consistent with metallic iron as a minor phase in the topmost lower mantle reported by laboratory studies. Velocity drops atop the 410-km discontinuity are observed surrounding the Alpine orogeny, suggesting upwelling of water-rich rock from the transition zone in response to the downwelled materials below the orogeny. Our results provide evidence that convective penetration of the mantle transition zone pushes hydrated minerals both upward and downward to add hydrogen to the surrounding mantle.

Three-dimensional models of deformation near strike-slip faults

USGS Publications Warehouse

ten Brink, Uri S.; Katzman, Rafael; Lin, J.

1996-01-01

We use three-dimensional elastic models to help guide the kinematic interpretation of crustal deformation associated with strike-slip faults. Deformation of the brittle upper crust in the vicinity of strike-slip fault systems is modeled with the assumption that upper crustal deformation is driven by the relative plate motion in the upper mantle. The driving motion is represented by displacement that is specified on the bottom of a 15-km-thick elastic upper crust everywhere except in a zone of finite width in the vicinity of the faults, which we term the "shear zone." Stress-free basal boundary conditions are specified within the shear zone. The basal driving displacement is either pure strike slip or strike slip with a small oblique component, and the geometry of the fault system includes a single fault, several parallel faults, and overlapping en echelon faults. We examine the variations in deformation due to changes in the width of the shear zone and due to changes in the shear strength of the faults. In models with weak faults the width of the shear zone has a considerable effect on the surficial extent and amplitude of the vertical and horizontal deformation and on the amount of rotation around horizontal and vertical axes. Strong fault models have more localized deformation at the tip of the faults, and the deformation is partly distributed outside the fault zone. The dimensions of large basins along strike-slip faults, such as the Rukwa and Dead Sea basins, and the absence of uplift around pull-apart basins fit models with weak faults better than models with strong faults. Our models also suggest that the length-to-width ratio of pull-apart basins depends on the width of the shear zone and the shear strength of the faults and is not constant as previously suggested. We show that pure strike-slip motion can produce tectonic features, such as elongate half grabens along a single fault, rotated blocks at the ends of parallel faults, or extension perpendicular to overlapping en echelon faults, which can be misinterpreted to indicate a regional component of extension. Zones of subsidence or uplift can become wider than expected for transform plate boundaries when a minor component of oblique motion is added to a system of parallel strike-slip faults.

Three-dimensional models of deformation near strike-slip faults

USGS Publications Warehouse

ten Brink, Uri S.; Katzman, Rafael; Lin, Jian

1996-01-01

We use three-dimensional elastic models to help guide the kinematic interpretation of crustal deformation associated with strike-slip faults. Deformation of the brittle upper crust in the vicinity of strike-slip fault systems is modeled with the assumption that upper crustal deformation is driven by the relative plate motion in the upper mantle. The driving motion is represented by displacement that is specified on the bottom of a 15-km-thick elastic upper crust everywhere except in a zone of finite width in the vicinity of the faults, which we term the “shear zone.” Stress-free basal boundary conditions are specified within the shear zone. The basal driving displacement is either pure strike slip or strike slip with a small oblique component, and the geometry of the fault system includes a single fault, several parallel faults, and overlapping en echelon faults. We examine the variations in deformation due to changes in the width of the shear zone and due to changes in the shear strength of the faults. In models with weak faults the width of the shear zone has a considerable effect on the surficial extent and amplitude of the vertical and horizontal deformation and on the amount of rotation around horizontal and vertical axes. Strong fault models have more localized deformation at the tip of the faults, and the deformation is partly distributed outside the fault zone. The dimensions of large basins along strike-slip faults, such as the Rukwa and Dead Sea basins, and the absence of uplift around pull-apart basins fit models with weak faults better than models with strong faults. Our models also suggest that the length-to-width ratio of pull-apart basins depends on the width of the shear zone and the shear strength of the faults and is not constant as previously suggested. We show that pure strike-slip motion can produce tectonic features, such as elongate half grabens along a single fault, rotated blocks at the ends of parallel faults, or extension perpendicular to overlapping en echelon faults, which can be misinterpreted to indicate a regional component of extension. Zones of subsidence or uplift can become wider than expected for transform plate boundaries when a minor component of oblique motion is added to a system of parallel strike-slip faults.

Crustal-scale shear zones and heterogeneous structure beneath the North Anatolian Fault Zone, Turkey, revealed by a high-density seismometer array

NASA Astrophysics Data System (ADS)

Kahraman, Metin; Cornwell, David G.; Thompson, David A.; Rost, Sebastian; Houseman, Gregory A.; Türkelli, Niyazi; Teoman, Uğur; Altuncu Poyraz, Selda; Utkucu, Murat; Gülen, Levent

2015-11-01

Continental scale deformation is often localised along strike-slip faults constituting considerable seismic hazard in many locations. Nonetheless, the depth extent and precise geometry of such faults, key factors in how strain is accumulated in the earthquake cycle and the assessment of seismic hazard, are poorly constrained in the mid to lower crust. Using a dense broadband network of 71 seismic stations with a nominal station spacing of 7 km in the vicinity of the 1999 Izmit earthquake we map previously unknown small-scale structure in the crust and upper mantle along this part of the North Anatolian Fault Zone (NAFZ). We show that lithological and structural variations exist in the upper, mid and lower crust on length scales of less than 10 km and less than 20 km in the upper mantle. The surface expression of the NAFZ in this region comprises two major branches; both are shown to continue at depth with differences in dip, depth extent and (possibly) width. We interpret a <10 km wide northern branch that passes downward into a shear zone that traverses the entire crust and penetrates the upper mantle to a depth of at least 50 km. The dip of this structure appears to decrease west-east from ∼90° to ∼65° to the north over a distance of 30 to 40 km. Deformation along the southern branch may be accommodated over a wider (>10 km) zone in the crust with a similar variation of dip but there is no clear evidence that this shear zone penetrates the Moho. Layers of anomalously low velocity in the mid crust (20-25 km depth) and high velocity in the lower crust (extending from depths of 28-30 km to the Moho) are best developed in the Armutlu-Almacik block between the two shear zones. A mafic lower crust, possibly resulting from ophiolitic obduction or magmatic intrusion, can best explain the coherent lower crustal structure of this block. Our images show that strain has developed in the lower crust beneath both northern and southern strands of the North Anatolian Fault. Our new high resolution images provide new insights into the structure and evolution of the NAFZ and show that a small and dense passive seismic network is able to image previously undetectable crust and upper mantle heterogeneity on lateral length scales of less than 10 km.

Linkages Between the Megathrust and Upper-plate Deformation: Lessons From the Deformational Dichotomy of the 2016 Kaikoura New Zealand Earthquake

NASA Astrophysics Data System (ADS)

Furlong, K. P.; Herman, M. W.

2017-12-01

Following the 2016 Mw 7.8 Kaikoura earthquake, the nature of the coseismic rupture was unclear. Seismological and tsunami evidence pointed to significant involvement of the subduction megathrust, while geodetic and field observations pointed to a shallow set of intra-crustal faults as the main participants during the earthquake. It now appears that the Kaikoura earthquake produced synchronous faulting on the plate boundary subduction interface - the megathrust - and on a suite of crustal faults above the rupture zone in the overlying plate. This Kaikoura-style earthquake, involving synchronous ruptures on multiple components of the plate boundary, may be an important mode of plate boundary deformation affecting seismic hazard along subduction zones. Here we propose a model to explain how these upper-plate faults are loaded during the periods between megathrust earthquakes and subsequently can rupture synchronously with the megathrust. Between megathrust earthquakes, horizontal compression, driven by plate convergence, locks the upper-plate faults, particularly those at higher angles to the convergence direction and the oblique plate motion of the subducting Pacific plate deforms the upper-plate in bulk shear. During the time interval of megathrust rupture, two things happen which directly affect the stress conditions acting on these upper-plate faults: (1) slip on the megathrust and the associated `rebound' of the upper plate reduces the compressive or normal stress acting on the upper plate faults, and (2) the base of the upper plate faults (and the upper plate itself) is decoupled from the slab in the region above rupture area. The reduction in normal stress acting on these faults increases their Coulomb Stress state to strongly favor strike-slip fault slip, and the basal decoupling of the upper plate allows it to undergo nearly complete stress recovery in that region; enabling the occurrence of very large offsets on these faults - offsets that exceed the slip on the plate interface. With these results it is clear that the 2016 Kaikoura NZ earthquake represents a mode of subduction zone rupture that must be considered in other regions.

Reactor for fluidized bed silane decomposition

NASA Technical Reports Server (NTRS)

Iya, Sridhar K. (Inventor)

1989-01-01

An improved heated fluidized bed reactor and method for the production of high purity polycrystalline silicon by silane pyrolysis wherein silicon seed particles are heated in an upper heating zone of the reactor and admixed with particles in a lower zone, in which zone a silane-containing gas stream, having passed through a lower cooled gas distribution zone not conducive to silane pyrolysis, contacts the heated seed particles whereon the silane is heterogeneously reduced to silicon.

Exceptionally well-preserved Permocalculus cf. tenellus (Pia) (Gymnocodiaceae) from Upper Permian Khuff Formation limestones, Saudi Arabia

NASA Astrophysics Data System (ADS)

Hughes, G. W.

2017-04-01

An exceptionally well-preserved specimen of the articulated rhodophyte Permocalculus, compared with P. tenellus sensu Elliott, 1955, is described from fine-grained Upper Permian limestones of the Khuff Formation of Saudi Arabia. Longitudinal medullary and sheaf-like cortical filaments extend through the uniserial series of elongate-globular, concave- and convex-terminating, interlocking segments for which they are interpreted to have functioned in articulation. The filaments tend to splay and branch laterally into the cortex where they terminate at the pores. At the terminal aperture, the filaments extend as bifurcating and possibly trifurcating branches and may serve as the origin of a new segment. Numerous elongate-globular chambers, up to five in each row and intimately involved with the filaments, are developed in the outer medulla and are considered to represent reproductive sporangia. The specimen is considered to have occupied predominantly low-energy, normal to slightly elevated salinity, shallow conditions within the subtidal regime of a lagoon.

Eighth report of the Normandy Archaeological Project: 1975 excavations at the Eoff I site (40CF32), Aaron Shelton site (40CF69) and the Duke I site (40CF97)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faulkner, C.H.; McCollough, C.R.

This report discusses the research conducted during the last full field season for the Normandy Archaeological Project. There was a deep sense of urgency to use all available resources to continue to test crucial hypotheses about subsistence and settlement patterns of the Middle Woodland and Mississippian cultures in the lower and upper reservoir zones. The most salient of these hypotheses were prehistoric agricultural societies in the upper Duck Valley, and exploitative strategies of prehistoric hunters and gatherers in the upper Duck Valley differed in the lower and upper reservoir zones. Since the early Mississippian Banks phase and the late Middlemore » Woodland Owl Hollow phase exhibited evidence for both food production and permanent settlement in the lower reservoir zone, a continued attempt was made to excavate those sites on which components of these two phase were found. Additional community pattern data and chronometric dates for the Banks phase were also sought since previously obtained radiocarbon assays indicated this was one of the earliest Mississippian cultures in the Middle South. The study of the origins and local development of this culture was also given priority status in Normandy Research. 145 refs., 33 figs., 94 tabs.« less

Genetic implications of the trace element distribution pattern in the upper knox carbonate rocks, copper ridge district, East Tennessee

NASA Astrophysics Data System (ADS)

Churnet, Habte G.; Misra, Kula C.

1981-11-01

The Lower Ordovician, Upper Knox Group rocks (the Kingsport and Mascot formations) in the Copper Ridge district consist predominantly of fine-grained dolostones, medium and coarser grained dolostones, and limestones. Dolomite crystals of medium and coarser grained dolostones show up to eight cathodoluminescent zones of variable width and intensity. Electron microprobe analyses indicate that the zoning is related to variation in Fe/Mn ratios, the brighter luminescent zones corresponding to lower ratios. Superposed on this growth zoning is a compositional zoning characterized by a general increase in Fe from core to rim of individual dolomite crystals. Field and petrographic studies (Churnet, 1979; Churnet et al., 1981) indicate that the fine-grained dolostones formed in supratidal to upper intratidal environments, whereas the precursor lime muds of the limestones as well as of the medium and coarser grained dolostones formed in shallow subtidal to lower intertidal environments. The large areal extent of the dolostones must have required a regionally abundant source of Mg such as marine water. Yet, both limestones and dolostones have low Na and Sr contents suggestive of their formation in solutions more dilute than normal marine water. It is proposed that the fine-grained dolostones formed by aggradation of initially very fine-grained dolostones in presence of fresh water, and that the limestones stabilized and the medium and coarser grained dolostones formed in environments of mixed marine and fresh waters. Considered in the light of ordering of partition coefficients, such a mixing model can account for the observed correlation pattern of trace elements (especially, SMn and SrFe) as well as the Fe distribution in the zoned dolomite crystals. Variation of the partition coefficient of Mn due to fluctuations in the relative proportions of fresh and marine waters in the diagenetic solution may explain the different Fe/Mn ratios observed in the growth zones (luminescence bands) of zoned dolomite crystals.

[Distribution characteristics of dissolved oxygen and mechanism of hypoxia in the upper estuarine zone of the Daliaohe River].

PubMed

Yang, Li-Na; Li, Zheng-Yan; Zhang, Xue-Qing

2011-01-01

Based on field surveys in the upper estuarine zone of the Daliaohe River in Spring and Summer of 2009, the spatial and temporal distributions of dissolved oxygen were analyzed and the mechanism of hypoxia were preliminarily discussed. The results indicated that DO concentrations were higher in the river mouth and lower in the upper reaches, higher in surface layers and lower in bottom concerning its spatial distribution. For its temporal distribution, DO concentrations were higher in daytime and lower at night, higher in Spring and lower in Summer. The DO concentrations in the upper estuarine zone of the Daliaohe River in Summer ranged between 1.36-4.77 mg/L with an average of 3.44 mg/L. The concentrations in the lower reaches were higher with an average of 3.94 mg/L. A large hypoxia area was recorded in Summer in the upper reaches of the estuary starting from about 45 km away from the river gate with an average DO concentration of 2.33 mg/L and a minimum of 1.36 mg/L. The correlation analysis showed that DO concentration was significantly correlated with nutrients and permanganate index. Excessive discharge of nutrients and organic pollutants were, therefore, main factors causing hypoxia, and water column stratification due to temperature rise in Summer in surface layers led to further reduction of DO in bottom layers of the water.

High-resolution seismic reflection imaging of growth folding and shallow faults beneath the Southern Puget Lowland, Washington State

USGS Publications Warehouse

Clement, C.R.; Pratt, T.L.; Holmes, M.L.; Sherrod, B.L.

2010-01-01

Marine seismic reflection data from southern Puget Sound, Washington, were collected to investigate the nature of shallow structures associated with the Tacoma fault zone and the Olympia structure. Growth folding and probable Holocene surface deformation were imaged within the Tacoma fault zone beneath Case and Carr Inlets. Shallow faults near potential field anomalies associated with the Olympia structure were imaged beneath Budd and Eld Inlets. Beneath Case Inlet, the Tacoma fault zone includes an ???350-m wide section of south-dipping strata forming the upper part of a fold (kink band) coincident with the southern edge of an uplifted shoreline terrace. An ???2 m change in the depth of the water bottom, onlapping postglacial sediments, and increasing stratal dips with increasing depth are consistent with late Pleistocene to Holocene postglacial growth folding above a blind fault. Geologic data across a topographic lineament on nearby land indicate recent uplift of late Holocene age. Profiles acquired in Carr Inlet 10 km to the east of Case Inlet showed late Pleistocene or Holocene faulting at one location with ???3 to 4 m of vertical displacement, south side up. North of this fault the data show several other disruptions and reflector terminations that could mark faults within the broad Tacoma fault zone. Seismic reflection profiles across part of the Olympia structure beneath southern Puget Sound show two apparent faults about 160 m apart having 1 to 2 m of displacement of subhorizontal bedding. Directly beneath one of these faults, a dipping reflector that may mark the base of a glacial channel shows the opposite sense of throw, suggesting strike-slip motion. Deeper seismic reflection profiles show disrupted strata beneath these faults but little apparent vertical offset, consistent with strike-slip faulting. These faults and folds indicate that the Tacoma fault and Olympia structure include active structures with probable postglacial motion.

On the Origin of the High Magnetization Zone Parallel to the Paleoproterozoic - Mesoproterozoic Southeastern Margin (Neodymium Line) of Laurentian United States

NASA Astrophysics Data System (ADS)

Durham, R.; Ravat, D.

2016-12-01

We investigate the geodyamical origin of an intriguing magnetic high zone along the SE margin of Paleoproterozoic provinces in the United States present in magnetic anomaly data. The SE edge of the high corresponds to the geochemical Nd-based crustal formation age boundary [Van Schmus et al., GSA Special Paper 308, 1996]. Since upper crustal magnetization does not show strong variation across this boundary, magnetization was expected to lie in the lower crust [Ravat, 2007, In: (eds.) Gubbins & Herrero-Bervera, Encycl. of Geomagn. and Paleomagn]. However, using 500 km spectral windows, determinations of the base of crustal magnetization from the De-fractal method [Salem et al., Tectonophysics, 2014; Ravat et al., AGU Fall Meeting, 2015] suggest it terminates in the middle to lower crust. A deeper layer of magnetization is suggested by larger (900-1200 km) windows. Because the juvenile crust in the region is formed from arc volcanism similar to the Mesoproterozoic provinces southeast of the Nd-boundary, it is difficult to imagine that the magnetization contrast of the provinces could be so different. Several magnetic highs along present-day subduction margins are associated with a serpentinized mantle wedge [Blakely et al., Geology, 2005]. Using magnetic modeling, we estimate end-members of magnetization, depth extent, and width of this zone of once-serpentinized high magnetization attached to the crust. The anomaly has variable width ( 250 km) with amplitude of approximately 200 nT. We also consider other magnetic sources such as crustal underplating to explain the source. Models requiring mantle magnetization require westward subduction pre-1.63 Ga, quick slab-rollback and break-off, and westward subduction of another slab preceding the Grenville terranes. Present geochemical models require initial eastward subduction changing in polarity to the west; however, this may not explain the zone of high magnetization in the mantle over the Paleoproterozoic terranes. These scenarios can also explain the Granite-Rhyolite provinces.

High-resolution seismic reflection imaging of growth folding and shallow faults beneath the Southern Puget Lowland, Washington State

USGS Publications Warehouse

Odum, Jackson K.; Stephenson, William J.; Pratt, Thomas L.; Blakely, Richard J.

2016-01-01

Marine seismic reflection data from southern Puget Sound, Washington, were collected to investigate the nature of shallow structures associated with the Tacoma fault zone and the Olympia structure. Growth folding and probable Holocene surface deformation were imaged within the Tacoma fault zone beneath Case and Carr Inlets. Shallow faults near potential field anomalies associated with the Olympia structure were imaged beneath Budd and Eld Inlets. Beneath Case Inlet, the Tacoma fault zone includes an ∼350-m wide section of south-dipping strata forming the upper part of a fold (kink band) coincident with the southern edge of an uplifted shoreline terrace. An ∼2 m change in the depth of the water bottom, onlapping postglacial sediments, and increasing stratal dips with increasing depth are consistent with late Pleistocene to Holocene postglacial growth folding above a blind fault. Geologic data across a topographic lineament on nearby land indicate recent uplift of late Holocene age. Profiles acquired in Carr Inlet 10 km to the east of Case Inlet showed late Pleistocene or Holocene faulting at one location with ∼3 to 4 m of vertical displacement, south side up. North of this fault the data show several other disruptions and reflector terminations that could mark faults within the broad Tacoma fault zone. Seismic reflection profiles across part of the Olympia structure beneath southern Puget Sound show two apparent faults about 160 m apart having 1 to 2 m of displacement of subhorizontal bedding. Directly beneath one of these faults, a dipping reflector that may mark the base of a glacial channel shows the opposite sense of throw, suggesting strike-slip motion. Deeper seismic reflection profiles show disrupted strata beneath these faults but little apparent vertical offset, consistent with strike-slip faulting. These faults and folds indicate that the Tacoma fault and Olympia structure include active structures with probable postglacial motion.

Shallow water mud-mounds of the Early Devonian Buchan Group, East Gippsland, Australia

NASA Astrophysics Data System (ADS)

Tosolini, A.-M. P.; Wallace, M. W.; Gallagher, S. J.

2012-12-01

The Lower Devonian Rocky Camp Member of the Murrindal Limestone, Buchan Group of southeastern Australia consists of a series of carbonate mud-mounds and smaller lagoonal bioherms. The Rocky Camp mound is the best exposed of the mud-mounds and has many characteristics in common with Waulsortian (Carboniferous) mounds. Detailed paleoecological and sedimentological studies indicate that the mound initially accumulated in the photic zone, in contrast to most of the previously recorded mud-mounds. Five facies are present in the mud-mound: a Dasycladacean Wackestone Facies at the base of the mound represents a moderate energy, shallow water bank environment within the photic zone. A Crinioidal Wackestone Facies was deposited in a laterally equivalent foreslope setting. A Poriferan-Crinoidal Mudstone Facies developed in a quiet, deeper water, lee-side mound setting associated with a minor relative sea-level rise. A Stromatoporoid-Coralline Packstone Facies in the upper part of the mound deposited in a high-energy, fair-weather wave base, mound-front environment. The crest of the mound is represented by a Crinoidal-Receptaculitid Packstone Facies indicative of a moderate-energy mound-top environment in the photic zone, sheltered by the mound-front stromatoporoid-coral communities. A mound flank facies is present on the southern side of the mound and this consists of high-energy crinoidal grainstones. Mud-mound deposition was terminated by a transgression that deposited dark gray, fossil-poor marl of the overlying Taravale Formation. The Rocky Camp mound appears to have originated in shallow water photic zone conditions and grew into a high-energy environment, with the mound being eventually colonized by corals and stromatoporoids. The indications of a high-energy environment during later mound growth (growth form of colonial metazoans and grainstones of the flanking facies) suggest that the micrite in the mound was autochthonous and implies the presence of an energy damping mechanism (probably biological) at the mound surface.

Provenance of upper Triassic sandstone, southwest Iberia (Alentejo and Algarve basins): tracing variability in the sources

NASA Astrophysics Data System (ADS)

Pereira, M. F.; Ribeiro, C.; Gama, C.; Drost, K.; Chichorro, M.; Vilallonga, F.; Hofmann, M.; Linnemann, U.

2017-01-01

Laser ablation ICP-MS U-Pb analyses have been conducted on detrital zircon of Upper Triassic sandstone from the Alentejo and Algarve basins in southwest Iberia. The predominance of Neoproterozoic, Devonian, Paleoproterozoic and Carboniferous detrital zircon ages confirms previous studies that indicate the locus of the sediment source of the late Triassic Alentejo Basin in the pre-Mesozoic basement of the South Portuguese and Ossa-Morena zones. Suitable sources for the Upper Triassic Algarve sandstone are the Upper Devonian-Lower Carboniferous of the South Portuguese Zone (Phyllite-Quartzite and Tercenas formations) and the Meguma Terrane (present-day in Nova Scotia). Spatial variations of the sediment sources of both Upper Triassic basins suggest a more complex history of drainage than previously documented involving other source rocks located outside present-day Iberia. The two Triassic basins were isolated from each other with the detrital transport being controlled by two independent drainage systems. This study is important for the reconstruction of the late Triassic paleogeography in a place where, later, the opening of the Central Atlantic Ocean took place separating Europe from North America.

75 FR 53193 - Safety Zone; Mississippi River, Mile 427.3 to 427.5

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-31

... Zone; Mississippi River, Mile 427.3 to 427.5 AGENCY: Coast Guard, DHS. ACTION: Temporary final rule... River, Mile 427.3 to 427.5, extending the entire width of the river. This safety zone is needed to... 5, 2010 the City of Keithsburg will be conducting a fireworks display at mile 427.4 on the Upper...

The morphology, processes, and evolution of Monterey Fan: a revisit

USGS Publications Warehouse

Gardner, James V.; Bohannon, Robert G.; Field, Michael E.; Masson, Douglas G.

2010-01-01

Long-range (GLORIA) and mid-range (TOBI) sidescan imagery and seismic-reflection profiles have revealed the surface morphology and architecture of the complete Monterey Fan. The fan has not developed a classic wedge shape because it has been blocked for much of its history by Morro Fracture Zone. The barrier has caused the fan to develop an upper-fan and lower-fan sequence that are distinctly different from one another. The upper-fan sequence is characterized by Monterey and Ascension Channels and associated Monterey Channel-levee system. The lower-fan sequence is characterized by depositional lobes of the Ascension, Monterey, and Sur-Parkington-Lucia systems, with the Monterey depositional lobe being the youngest. Presently, the Monterey depositional lobe is being downcut because the system has reached a new, lower base level in the Murray Fracture Zone. A five-step evolution of Monterey Fan is presented, starting with initial fan deposition in the Late Miocene, about 5.5 Ma. This first stage was one of filling bathymetric lows in the oceanic basement in what was to become the upper-fan segment. The second stage involved filling the bathymetric low on the north side of Morro Fracture Zone, and probably not much sediment was transported beyond the fracture zone. The third stage witnessed sediment being transported around both ends of Morro Fracture Zone and initial sedimentation on the lower-fan segment. During the fourth stage Ascension Channel was diverted into Monterey Channel, thereby cutting off sedimentation to the Ascension depositional lobe.

Municipal water supplies in Lee County, Florida, 1974

USGS Publications Warehouse

O'Donnell, T. H.

1977-01-01

In 1974 the total pumpage for Lee County, Fla., municipal supplies reached 5,700 Mgal (million gallons annually), an increase of 54 percent over 1970 levels. Pumpage from individual sources included: Caloosahatchee River, 1,312 Mgal; water-table aquifer, 2,171 Mgal; the water-bearing zone in the Tamiami Formation, 340 Mgal; the water-bearing zone in the upper part of the Hawthorn Formation, 1,399 Mgal; the saline water zones in the lower part of the Hawthorn Formation and the Suwannee Limestone, 483 Mgal. Among the various sources, the water-table aquifer showed the greatest increase in municipal pumpage over 1970 levels (60 percent) while the saline zones in the lower part of the Hawthorn Formation and Suwannee Limestone showed the least (40 percent). Intensive pumpage from the water bearing zone in the upper part of the Hawthorn Formation has caused a progressive decline in water levels in wells tapping that zone. The quality of fresh ground water in areas unaffected by intrusion of saline water, generally meets all the recommended limits of the Environmental Protection Agency. The chemical treatment processes utilized by water plants in the county are generally effective in producing finished water that meets EPA preliminary drinking water standards. (Woodard-USGS)

Imaging the deep structures of the convergent plates along the Ecuadorian subduction zone through receiver function analysis

NASA Astrophysics Data System (ADS)

Galve, A.; Charvis, P.; Regnier, M. M.; Font, Y.; Nocquet, J. M.; Segovia, M.

2017-12-01

The Ecuadorian subduction zone was affected by several large M>7.5 earthquakes. While we have low resolution on the 1942, 1958 earthquakes rupture zones extension, the 2016 Pedernales earthquake, that occurs at the same location than the 1942 earthquake, give strong constraints on the deep limit of the seismogenic zone. This downdip limit is caused by the onset of plasticity at a critical temperature (> 350-450 °C for crustal materials, or serpentinized mantle wedge, and eventually > 700 °C for dry mantle). However we still don't know exactly where is the upper plate Moho and therefore what controls the downdip limit of Ecuadorian large earthquakes seismogenic zone. For several years Géoazur and IG-EPN have maintained permanent and temporary networks (ADN and JUAN projects) along the margin to register the subduction zone seismological activity. Although Ecuador is not a good place to perform receiver function due to its position with respect to the worldwide teleseismic sources, the very long time deployment compensate this issue. We performed a frequency dependent receiver function analysis to derive (1) the thickness of the downgoing plate, (2) the interplate depth and (3) the upper plate Moho. These constraints give the frame to interpretation on the seismogenic zone of the 2016 Pedernales earthquake.

Magnetic Susceptibility and Mineral Zonations Controlled by Provenance in Loess along the Illinois and Central Mississippi River Valleys

USGS Publications Warehouse

Grimley, D.A.; Follmer, L.R.; McKay, E.D.

1998-01-01

Magnetic susceptibility (MS) patterns have proven useful for regional stratigraphic correlations of zones within thick, oxidized Peoria and Roxana Silts along the Illinois and Central Mississippi River valleys for more than 350 km. Variations in MS of C horizon loess are controlled by silt-sized magnetite content and are interpreted to reflect changes in sediment provenance due to fluctuations of the Superior and Lake Michigan glacier lobes and the diversion of the Mississippi River to its present course. Grain size distributions and scanning electron microscopic observations indicate that stratigraphic changes in MS are not significantly influenced by eolian sorting or diagenetic dissolution, respectively. Three compositional zones (lower, middle, and upper) are delineated within Peoria Silt which usually can be traced in the field by MS, the occurrence of clay beds, interstadial soils, and/or subtle color changes. These zones can be correlated with, but are generally of more practical use than, previously studied dolomite zones (McKay, 1977) or clay mineral zones (Frye et al., 1968). However, mineralogical analyses can help to substantiate zone boundaries when in question. MS and compositional zones may indirectly record a climatic signal, primarily through the effect that global cooling has had on ice lobe fluctuations in the Upper Mississippi drainage basin. ?? 1998 University of Washington.

Audio-frequency magnetotelluric imaging of the Hijima fault, Yamasaki fault system, southwest Japan

NASA Astrophysics Data System (ADS)

Yamaguchi, S.; Ogawa, Y.; Fuji-Ta, K.; Ujihara, N.; Inokuchi, H.; Oshiman, N.

2010-04-01

An audio-frequency magnetotelluric (AMT) survey was undertaken at ten sites along a transect across the Hijima fault, a major segment of the Yamasaki fault system, Japan. The data were subjected to dimensionality analysis, following which two-dimensional inversions for the TE and TM modes were carried out. This model is characterized by (1) a clear resistivity boundary that coincides with the downward projection of the surface trace of the Hijima fault, (2) a resistive zone (>500 Ω m) that corresponds to Mesozoic sediment, and (3) shallow and deep two highly conductive zones (30-40 Ω m) along the fault. The shallow conductive zone is a common feature of the Yamasaki fault system, whereas the deep conductor is a newly discovered feature at depths of 800-1,800 m to the southwest of the fault. The conductor is truncated by the Hijima fault to the northeast, and its upper boundary is the resistive zone. Both conductors are interpreted to represent a combination of clay minerals and a fluid network within a fault-related fracture zone. In terms of the development of the fluid networks, the fault core of the Hijima fault and the highly resistive zone may play important roles as barriers to fluid flow on the northeast and upper sides of the conductive zones, respectively.

Occurrence and use of ground water in the Venice-Englewood area, Sarasota and Charlotte counties, Florida

USGS Publications Warehouse

Sutcliffe, Horace; Thompson, Thomas H.

1983-01-01

In a 75-square-mile area of coastal Sarasota and Charlotte Counties, demand for water is increasing. Groundwater, the principal source of supply, is distributed largely by public water systems. Principal water-bearing formations in descending order, include the surficial aquifer, artesian zone 1 in the Tamiami Formation, zone 2 in the upper part of the Hawthorn Formation, zone 3 in the lower part of the Hawthorn Formation and upper part of the Tampa Limestone, and zones 4 and 5 which comprise the Floridan aquifer. The surficial aquifer, except near tidewater, provides limited supplies of freshwater to wells. Artesian zone 1 is the major aquifer for public supply. It is contaminated by saline water in some areas, either as a result of inundation by storm-driven tides or by upwar leakage of mineralized water from underlying aquifers through uncased or improperly constructed wells. The city of Venice obtains some water from zone 2, but the water is brackish in much of the area. The water is suitable for irrigation in parts of the area. Except for local use of water for watering livestock and maintaining ponds, the water from zones 3, 4, and 5 is little used because of its poor quality. (USGS)

Petrologic and chemical changes in ductile shear zones as a function of depth in the continental crust

NASA Astrophysics Data System (ADS)

Yang, Xin-Yue

Petrologic and geochemical changes in ductile shear zones are important for understanding deformational and geochemical processes of the continental crust. This study examines three shear zones that formed under conditions varying from lower greenschist facies to upper amphibolite facies in order to document the petrologic and geochemical changes of deformed rocks at various metamorphic grades. The studied shear zones include two greenschist facies shear zones in the southern Appalachians and an upper amphibolite facies shear zone in southern Ontario. The mylonitic gneisses and mylonites in the Roses Mill shear zone of central Virginia are derived from a ferrodiorite protolith and characterized by a lower greenschist facies mineral assemblage. Both pressure solution and recrystallization were operative deformation mechanisms during mylonitization in this shear zone. Strain-driven dissolution and solution transfer played an important role in the mobilization of felsic components (Si, Al, K, Na, and Ca). During mylonitization, 17% to 32% bulk rock volume losses of mylonites are mainly attributed to removal of these mobile felsic components by a fluid phase. Mafic components (Fe, Mg, Ti, Mn and P) and trace elements, REE, Y, V and Sc, were immobile. At Rosman, North Carolina, the Brevard shear zone (BSZ) shows a deformational transition from the coarse-grained Henderson augen gneiss (HAG) to proto-mylonite, mylonite and ultra-mylonite. The mylonites contain a retrograde mineral assemblage as a product of fluid-assisted chemical breakdown of K-feldspar and biotite at higher greenschist facies conditions. Recrystallization and intra-crystalline plastic deformation are major deformation mechanisms in the BSZ. Fluid-assisted mylonitization in the BSZ led to 6% to 23% bulk volume losses in mylonites. During mylonitization, both major felsic and mafic elements and trace elements, Rb, Sr, Zr, V, Sc, and LREE were mobile; however, the HREEs were likely immobile. A shear zone in the Parry Sound domain, Ontario, formed at upper amphibolite facies conditions. The deformation process of the shear zone involves fully plastic deformation and high-temperature dynamic recrystallization and annealing recovery of both quartz and plagioclase. Geochemical evidence indicates that the chemical changes in the deformed rocks resulted from mixing of mafic and felsic layers together with fluid-assisted mass transfer within the shear zone. A geochemical model that incorporates closed-system two-component mixing with open-system mass transfer can well explain the observed major and trace element data.

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING SOUTH TOWARD ...

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

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING SOUTH TOWARD THE FRONT OF THE STRUCTURE. THE WHEELS AT THE TOP OF THE TRAM BUCKETS RODE OFF THE STATIONARY CABLES ONTO THE TRACK SUPPORTED BY THE "C" IRONS SUSPENDED FROM THE TOP TIMBERS ON THE LEFT AND RIGHT. THE BUCKET OPENING MECHANISM IS ON THE LEFT, AND PART OF THE CLOSING MECHANISM ON THE RIGHT EDGE OF THE FRAME. THE TWO CABLES AT CENTER ARE THE STATIONARY TRAM CABLES THAT RUN ALONG THE TOP OF THE SUPPORT TOWERS ON WHICH THE WHEELS OF THE TRAM BUCKETS RODE. THEY ARE ANCHORED AT GROUND LEVEL JUST OFF FRAME TO THE LOWER LEFT. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

Musculoskeletal symptoms of the upper extremities and the neck: A cross-sectional study on prevalence and symptom-predicting factors at visual display terminal (VDT) workstations

PubMed Central

Klussmann, André; Gebhardt, Hansjuergen; Liebers, Falk; Rieger, Monika A

2008-01-01

Background The aim of this study was to determine the prevalence and the predictors of musculoskeletal symptoms in the upper extremities and neck at visual display terminal (VDT) workstations. Methods In a cross-sectional study 1,065 employees working at VDT > 1 h/d completed a standardised questionnaire. Workstation conditions were documented in a standardised checklist, and a subgroup of 82 employees underwent a physical examination. Results Using the Nordic Questionnaire, the 12-month prevalence of symptoms of the neck, shoulder region, hand/wrist, or elbow/lower arm was 55%, 38%, 21%, and 15% respectively. The duration of VDT work had a significant impact on the frequency of neck symptoms in employees performing such work > 6 h/d. Conclusion With regard to musculoskeletal symptoms of the upper extremities, preventive measures at VDT workstations should be focused on neck and shoulder symptoms (e.g. ergonomic measures, breaks to avoid sitting over long periods). PMID:18588677

76 FR 9744 - Reorganization of Foreign-Trade Zone 181 under Alternative Site Framework; Akron/Canton, OH

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-22

... categorized as magnet sites, and the grantee proposes an additional magnet site (Site 29); Whereas, notice...-year ASF sunset provision for magnet sites that would terminate authority for Sites 3-5, 8, 10, 11, 14... for magnet sites that would terminate authority for Sites 6, 9, 12, 13, 22 and 24 if not activated by...

Evidence for fluid and melt generation in response to an asthenospheric upwelling beneath the Hangai Dome, Mongolia

NASA Astrophysics Data System (ADS)

Comeau, Matthew J.; Käufl, Johannes S.; Becken, Michael; Kuvshinov, Alexey; Grayver, Alexander V.; Kamm, Jochen; Demberel, Sodnomsambuu; Sukhbaatar, Usnikh; Batmagnai, Erdenechimeg

2018-04-01

The Hangai Dome, Mongolia, is an unusual high-elevation, intra-continental plateau characterized by dispersed, low-volume, intraplate volcanism. Its subsurface structure and its origin remains unexplained, due in part to a lack of high-resolution geophysical data. Magnetotelluric data along a ∼610 km profile crossing the Hangai Dome were used to generate electrical resistivity models of the crust and upper mantle. The crust is found to be unexpectedly heterogeneous. The upper crust is highly resistive but contains several features interpreted as ancient fluid pathways and fault zones, including the South Hangai fault system and ophiolite belt that is revealed to be a major crustal boundary. South of the Hangai Dome a clear transition in crustal properties is observed which reflects the rheological differences across accreted terranes. The lower crust contains discrete zones of low-resistivity material that indicate the presence of fluids and a weakened lower crust. The upper mantle contains a large low-resistivity zone that is consistent with the presence of partial melt within an asthenospheric upwelling, believed to be driving intraplate volcanism and supporting uplift.

33 CFR 165.703 - Tampa Bay, Florida-Safety Zone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... loaded anhydrous ammonia vessel and the width of the channel in the following areas: (1) For inbound tank vessels loaded with anhydrous ammonia, Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” north... anhydrous ammonia receiving terminals to Port Sutton the safety zone includes, in addition to the area in...

33 CFR 165.703 - Tampa Bay, Florida-Safety Zone.

Code of Federal Regulations, 2014 CFR

2014-07-01

... loaded anhydrous ammonia vessel and the width of the channel in the following areas: (1) For inbound tank vessels loaded with anhydrous ammonia, Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” north... anhydrous ammonia receiving terminals to Port Sutton the safety zone includes, in addition to the area in...

33 CFR 165.703 - Tampa Bay, Florida-Safety Zone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... loaded anhydrous ammonia vessel and the width of the channel in the following areas: (1) For inbound tank vessels loaded with anhydrous ammonia, Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” north... anhydrous ammonia receiving terminals to Port Sutton the safety zone includes, in addition to the area in...

33 CFR 165.703 - Tampa Bay, Florida-Safety Zone.

Code of Federal Regulations, 2012 CFR

2012-07-01

... loaded anhydrous ammonia vessel and the width of the channel in the following areas: (1) For inbound tank vessels loaded with anhydrous ammonia, Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” north... anhydrous ammonia receiving terminals to Port Sutton the safety zone includes, in addition to the area in...

33 CFR 165.703 - Tampa Bay, Florida-Safety Zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... loaded anhydrous ammonia vessel and the width of the channel in the following areas: (1) For inbound tank vessels loaded with anhydrous ammonia, Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” north... anhydrous ammonia receiving terminals to Port Sutton the safety zone includes, in addition to the area in...

77 FR 14493 - Reorganization/Expansion of Foreign-Trade Zone 77 Under Alternative Site Framework Memphis...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-12

... [Order No. 1817] Reorganization/Expansion of Foreign-Trade Zone 77 Under Alternative Site Framework... project, to a five-year ASF sunset provision for magnet sites that would terminate authority for Site 4 if not activated by February 28, 2017, and to a three-year ASF sunset provision for usage-driven sites...

Results of borehole geophysical logging and aquifer-isolation tests conducted in the John Wagner and Sons, Inc. former production well, Ivyland, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.

1997-01-01

A suite of borehole geophysical logs and heat-pulse-flowmeter measurements run in the former production well at the John Wagner and Sons, Inc. plant indicate two zones of borehole flow. In the upper part of the well, water enters the borehole through a fracture at 90 ft (feet) below floor level, moves upward, and exits the borehole through a fracture at 72 ft below floor level. Water also enters the borehole through fractures at 205-213, 235, and 357 ft below floor level; moves downward; and exits the borehole through fractures at 450-459, 468-470, and 483-490 ft below floor level. Five zones were selected for aquifer-isolation (packer) tests on the basis of borehole geophysical logs. The zones were isolated using a straddle-packer assembly. The lowermost three zones (below 248, 223 to 248, and 198 to 223 ft below floor level) were hydraulically isolated from zones above and below. Specific capacities were 0.12, 0.034, and 0.15 gallons per minute per foot, respectively. The hydrograph from zone 2 (223 to 248 ft below floor level) showed interference from a nearby pumping well. For the upper two zones (81 to 106 and 57 to 81 ft below floor level), similar drawdowns in the isolated zone and the zones above and below the isolated zone indicate that these fractures are hydraulically connected outside the borehole in the unconfined part of the Stockton Formation. The specific capacity of zones 4 and 5 are similar—0.82 and 0.61, respectively.

Widespread gas hydrate instability on the upper U.S. Beaufort margin

USGS Publications Warehouse

Phrampus, Benjamin J.; Hornbach, Matthew J.; Ruppel, Carolyn D.; Hart, Patrick E.

2014-01-01

The most climate-sensitive methane hydrate deposits occur on upper continental slopes at depths close to the minimum pressure and maximum temperature for gas hydrate stability. At these water depths, small perturbations in intermediate ocean water temperatures can lead to gas hydrate dissociation. The Arctic Ocean has experienced more dramatic warming than lower latitudes, but observational data have not been used to study the interplay between upper slope gas hydrates and warming ocean waters. Here we use (a) legacy seismic data that constrain upper slope gas hydrate distributions on the U.S. Beaufort Sea margin, (b) Alaskan North Slope borehole data and offshore thermal gradients determined from gas hydrate stability zone thickness to infer regional heat flow, and (c) 1088 direct measurements to characterize multidecadal intermediate ocean warming in the U.S. Beaufort Sea. Combining these data with a three-dimensional thermal model shows that the observed gas hydrate stability zone is too deep by 100 to 250 m. The disparity can be partially attributed to several processes, but the most important is the reequilibration (thinning) of gas hydrates in response to significant (~0.5°C at 2σ certainty) warming of intermediate ocean temperatures over 39 years in a depth range that brackets the upper slope extent of the gas hydrate stability zone. Even in the absence of additional ocean warming, 0.44 to 2.2 Gt of methane could be released from reequilibrating gas hydrates into the sediments underlying an area of ~5–7.5 × 103 km2 on the U.S. Beaufort Sea upper slope during the next century.

Seismic Structure of the Antarctic Upper Mantle and Transition Zone Unearthed by Full Waveform Adjoint Tomography

NASA Astrophysics Data System (ADS)

Lloyd, A. J.; Wiens, D.; Zhu, H.; Tromp, J.; Nyblade, A.; Anandakrishnan, S.; Aster, R. C.; Huerta, A. D.; Winberry, J. P.; Wilson, T. J.; Dalziel, I. W. D.; Hansen, S. E.; Shore, P.

2017-12-01

The upper mantle and transition zone beneath Antarctica and the surrounding ocean are among the poorest seismically imaged regions of the Earth's interior. Over the last 1.5 decades researchers have deployed several large temporary broadband seismic arrays focusing on major tectonic features in the Antarctic. The broader international community has also facilitated further instrumentation of the continent, often operating stations in additional regions. As of 2016, waveforms are available from almost 300 unique station locations. Using these stations along with 26 southern mid-latitude seismic stations we have imaged the seismic structure of the upper mantle and transition zone using full waveform adjoint techniques. The full waveform adjoint inversion assimilates phase observations from 3-component seismograms containing P, S, Rayleigh, and Love waves, including reflections and overtones, from 270 earthquakes (5.5 ≤ Mw ≤ 7.0) that occurred between 2001-2003 and 2007-2016. We present the major results of the full waveform adjoint inversion following 20 iterations, resulting in a continental-scale seismic model (ANT_20) with regional-scale resolution. Within East Antarctica, ANT_20 reveals internal seismic heterogeneity and differences in lithospheric thickness. For example, fast seismic velocities extending to 200-300 km depth are imaged beneath both Wilkes Land and the Gamburtsev Subglacial Mountains, whereas fast velocities only extend to 100-200 km depth beneath the Lambert Graben and Enderby Land. Furthermore, fast velocities are not found beneath portions of Dronning Maud Land, suggesting old cratonic lithosphere may be absent. Beneath West Antarctica slow upper mantle seismic velocities are imaged extending from the Balleny Island southward along the Transantarctic Mountains front, and broaden beneath the southern and northern portion of the mountain range. In addition, slow upper mantle velocities are imaged beneath the West Antarctic coast extending from Marie Byrd Land to the Antarctic Peninsula. This region of slow velocity only extends to 150-200 km depth beneath the Antarctic Peninsula, while elsewhere it extends to deeper upper mantle depths and possibly into the transition zone as well as offshore, suggesting two different geodynamic processes are at play.

Effect of the focal plane position on CO2 laser beam cutting of injection molded polycarbonate sheets

NASA Astrophysics Data System (ADS)

Moradi, Mahmoud; Mehrabi, Omid; Azdast, Taher; Benyounis, Khaled Y.

2016-11-01

In the present research, the effect of laser beam focal plane position (FPP) on the kerf quality of the polycarbonate laser cutting is investigated. Low power CO2 laser is used as the heat source of the cutting runs. In the experiments, FPP is varied from 0 to -4mm while other processing parameters (i.e. laser power, cutting speed and gas pressure) are considered constant. Upper and lower kerf width, kerf taper, upper heat affected zone and surface roughness of the kerf wall are also considered as the responses. Observations signified that reducing the position of the laser beam focal point from zero to - 3mm reduces the upper and lower kerf width. However reducing FPP below -3mm leads to an increase in the kerf width. Results also reveals that upper heat affected zone value reduces by reduction in FPP. Moreover the best kerf wall surface roughness occurred at FPP= -3mm.

Global Ocean Phytoplankton

NASA Technical Reports Server (NTRS)

Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.

2013-01-01

Phytoplankton are free-floating algae that grow in the euphotic zone of the upper ocean, converting carbon dioxide, sunlight, and available nutrients into organic carbon through photosynthesis. Despite their microscopic size, these photoautotrophs are responsible for roughly half the net primary production on Earth (NPP; gross primary production minus respiration), fixing atmospheric CO2 into food that fuels our global ocean ecosystems. Phytoplankton thus play a critical role in the global carbon cycle, and their growth patterns are highly sensitive to environmental changes such as increased ocean temperatures that stratify the water column and prohibit the transfer of cold, nutrient richwaters to the upper ocean euphotic zone.

Scaly fabrics and veins of the Mugi and Makimine mélanges in the Shimanto belt, SW Japan

NASA Astrophysics Data System (ADS)

Ramirez, G. E.; Fisher, D. M.; Yamaguchi, A.; Kimura, G.

2016-12-01

Two regionally extensive ancient subduction fault zones provide a microstructural record of the plate boundary deformation associated with underthrusting. These rocks exhibit many of the characteristics associated with exposed ancient subduction fault zones worldwide, including: (1) σ1 is near orthogonal to the deformation fabric (2) there are microstructurally pervasive quartz and calcite filled veins concentrated in coarser blocks and along extensional jogs on slip surfaces, (3) evidence for local diffusion of silica sourced from web-like arrays of slip surfaces (i.e., scaly fabrics), and (4) evidence for cycles of cracking and sealing that record cyclic variations in stress. We present new backscatter SEM observations of scaly fabrics from two ancient subduction-related shear zones from the Shimanto Belt in Japan that exemplify these characteristics and represent the full temperature range of the seismogenic zone: 1) the Mugi mélange (lower ( 130-150 °C) and upper ( 170-200 °C) sections) and 2) Makimine mélange (peak temperatures of 340 °C). The Mugi mélange is an underplated duplex consisting of two horses separated by an OOST. The upper section is bounded at the top by a pseudotachylite-bearing paleodécollement. The Makimine mélange was underplated at the downdip limit of the seismogenic zone. The scaly fabrics associated with these shear zones display significantly different microstructural characteristics. A slip surface from along the upper Mugi is characterized by broader ( 20-30 μm), zones of quartz-poor, anastomosing shear zones composed of fine-grained (0.5-2 μm in length) phyllosilicates. The Makimine mélange exhibits thinner (10-20 μm), anastomosing shear zones with coarser (1-4 μm in length) phyllosilicate grains that are more strongly oriented into parallelism with slip surfaces. Quartz veins are pervasively developed in more competent blocks and are oriented at near perpendicular angles to the slip surfaces. Microstructural analyses of ancient subduction-related faults show differences with temperature that highlight the importance of establishing the geochemical processes and activation energies that contribute to slip, fracturing, and healing of rocks that underthrust the subduction interface.

Geophysical characteristics of the hydrothermal systems of Kilauea volcano, Hawaii

USGS Publications Warehouse

Kauahikaua, J.

1993-01-01

Clues to the overall structure of Kilauea volcano can be obtained from spatial studies of gravity, magnetic, and seismic velocity variations. The rift zones and summit are underlain by dense, magnetic, high P-wave-velocity rocks at depths of about 2 km less. The gravity and seismic velocity studies indicate that the rift structures are broad, extending farther to the north than to the south of the surface features. The magnetic data give more definition to the rift structures by allowing separation into a narrow, highly-magnetized, shallow zone and broad, flanking, magnetic lows. The patterns of gravity, magnetic variations, and seismicity document the southward migration of the upper cast rift zone. Regional, hydrologic features of Kilauea can be determined from resistivity and self-potential studies. High-level groundwater exists beneath Kilauea summit to elevations of +800 m within a triangular area bounded by the west edge of the upper southwest rift zone, the east edge of the upper east rift zone, and the Koa'c fault system. High-level groundwater is present within the east rift zone beyond the triangular summit area. Self-potential mapping shows that areas of local heat produce local fluid circulation in the unconfined aquifer (water table). The dynamics of Kilauea eruptions are responsible for both the source of heat and the fracture permeability of the hydrothermal system. Shallow seismicity and surface deformation indicate that magma is intruding and that fractures are forming beneath the rift zones and summit area. Magma supply estimates are used to calculate the rate of heat input to Kilauea's hydrothermal systems. Heat flows of 370-820 mW/m2 are calculated from deep wells within the lower east rift zone. The estimated heat input rate for Kilauea of 9 gigawatts (GW) is at least 25 times higher than the conductive heat loss as estimated from the heat flow in wells extrapolated over the area of the summit caldera and rift zones. Heat must be dissipated by another mechanism, or the heat input rate estimates are much too high. ?? 1993.

Oblique reactivation of lithosphere-scale lineaments controls rift physiography - the upper-crustal expression of the Sorgenfrei-Tornquist Zone, offshore southern Norway

NASA Astrophysics Data System (ADS)

Phillips, Thomas B.; Jackson, Christopher A.-L.; Bell, Rebecca E.; Duffy, Oliver B.

2018-04-01

Pre-existing structures within sub-crustal lithosphere may localise stresses during subsequent tectonic events, resulting in complex fault systems at upper-crustal levels. As these sub-crustal structures are difficult to resolve at great depths, the evolution of kinematically and perhaps geometrically linked upper-crustal fault populations can offer insights into their deformation history, including when and how they reactivate and accommodate stresses during later tectonic events. In this study, we use borehole-constrained 2-D and 3-D seismic reflection data to investigate the structural development of the Farsund Basin, offshore southern Norway. We use throw-length (T-x) analysis and fault displacement backstripping techniques to determine the geometric and kinematic evolution of N-S- and E-W-striking upper-crustal fault populations during the multiphase evolution of the Farsund Basin. N-S-striking faults were active during the Triassic, prior to a period of sinistral strike-slip activity along E-W-striking faults during the Early Jurassic, which represented a hitherto undocumented phase of activity in this area. These E-W-striking upper-crustal faults are later obliquely reactivated under a dextral stress regime during the Early Cretaceous, with new faults also propagating away from pre-existing ones, representing a switch to a predominantly dextral sense of motion. The E-W faults within the Farsund Basin are interpreted to extend through the crust to the Moho and link with the Sorgenfrei-Tornquist Zone, a lithosphere-scale lineament, identified within the sub-crustal lithosphere, that extends > 1000 km across central Europe. Based on this geometric linkage, we infer that the E-W-striking faults represent the upper-crustal component of the Sorgenfrei-Tornquist Zone and that the Sorgenfrei-Tornquist Zone represents a long-lived lithosphere-scale lineament that is periodically reactivated throughout its protracted geological history. The upper-crustal component of the lineament is reactivated in a range of tectonic styles, including both sinistral and dextral strike-slip motions, with the geometry and kinematics of these faults often inconsistent with what may otherwise be inferred from regional tectonics alone. Understanding these different styles of reactivation not only allows us to better understand the influence of sub-crustal lithospheric structure on rifting but also offers insights into the prevailing stress field during regional tectonic events.

Least-cost control of agricultural nutrient contributions to the Gulf of Mexico hypoxic zone.

PubMed

Rabotyagov, Sergey; Campbell, Todd; Jha, Manoj; Gassman, Philip W; Arnold, Jeffrey; Kurkalova, Lyubov; Secchi, Silvia; Feng, Hongli; Kling, Catherine L

2010-09-01

In 2008, the hypoxic zone in the Gulf of Mexico, measuring 20 720 km2, was one of the two largest reported since measurement of the zone began in 1985. The extent of the hypoxic zone is related to nitrogen and phosphorous loadings originating on agricultural fields in the upper Midwest. This study combines the tools of evolutionary computation with a water quality model and cost data to develop a trade-off frontier for the Upper Mississippi River Basin specifying the least cost of achieving nutrient reductions and the location of the agricultural conservation practices needed. The frontier allows policymakers and stakeholders to explicitly see the trade-offs between cost and nutrient reductions. For example, the cost of reducing annual nitrate-N loadings by 30% is estimated to be US$1.4 billion/year, with a concomitant 36% reduction in P and the cost of reducing annual P loadings by 30% is estimated to be US$370 million/year, with a concomitant 9% reduction in nitrate-N.

Effects of the types of overlap on the mechanical properties of FSSW welded AZ series magnesium alloy joints

NASA Astrophysics Data System (ADS)

Wang, Dan; Shen, Jun; Wang, Lin-Zhi

2012-03-01

The effects of the types of overlap on the mechanical properties of the friction stir spot welding (FSSW) welded AZ series magnesium alloy joints were investigated by microstructural observations, microhardness tests, and tensile tests. The results show that the microstructure of the stir zone adjacent to the periphery of the rotating pin is mainly composed of the upper sheet. The average distance D between the longitudinal segment of the curved interface and the keyhole periphery, the tensile shear force, and the microhardness of the stir zone of the FSSW welded AZ61 alloy joint are the highest in all samples. During FSSW of AZ31 and AZ61 dissimilar magnesium alloys, the irregular deformation of the longitudinal segment of the curved interface appears, while the microhardness of the stir zone is higher when AZ61 alloy is the upper sheet. Moreover, the microhardness of the stir zone increases initially and then decreases sharply in the longitudinal test position.

Water levels and artesian pressures in the Chad Basin of northeastern Nigeria, 1963-68

USGS Publications Warehouse

Carmalt, S.W.; Tibbitts, G.C.

1969-01-01

This report presents records of water levels and artesian pressures collected during 1963-68 on an observational network of 116 dug wells and boreholes (drilled wells) in the Chad Basin of northeastern Nigeria. The Chad Basin is underlain by the Chad Formation, a series of fluvio-lacustrine sediments which attain a thickness of 1,500 feet or more in Nigeria. Three water-bearing zones, designated Upper, Middle and Lower, have been identified in the Chad Formation of Nigeria. The Upper Zone aquifer, which contains water under both unconfined and confined conditions, provides the principal source of water to dug wells for domestic and village water supply. The Middle Zone aquifer is tapped by numerous deep boreholes (drilled wells) which provide water by artesian flow in more than 13,000 square miles of Nigeria north and east of Maiduguri. The Lower Zone, which is also confined has only been identified thus far (1969) in the vicinity of Maiduguri.

15 CFR 923.84 - Routine program changes.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management...

15 CFR 923.84 - Routine program changes.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management...

High-Resolution P'P' Precursor Imaging of Nazca-South America Plate Boundary Zones and Inferences for Transition Zone Temperature and Composition

NASA Astrophysics Data System (ADS)

Gu, Y. J.; Schultz, R.

2013-12-01

Knowledge of upper mantle transition zone stratification and composition is highly dependent on our ability to efficiently extract and properly interpret small seismic arrivals. A promising high-frequency seismic phase group particularly suitable for a global analysis is P'P' precursors, which are capable of resolving mantle structures at vertical and lateral resolution of approximately 5 and 200 km, respectively, owing to their shallow incidence angle and small, quasi-symmetric Fresnel zones. This study presents a simultaneous analysis of SS and P'P' precursors based on deconvolution, Radon transform and depth migration. Our multi-resolution survey of the mantle near Nazca-South America subduction zone reveals both olivine and garnet related transitions at depth below 400 km. We attribute a depressed 660 to thermal variations, whereas compositional variations atop the upper-mantle transition zone are needed to explain the diminished or highly complex reflected/scattered signals from the 410 km discontinuity. We also observe prominent P'P' reflections within the transition zone, especially near the plate boundary zone where anomalously high reflection amplitudes result from a sharp (~10 km thick) mineral phase change resonant with the dominant frequency of the P'P' precursors. Near the base of the upper mantle, the migration of SS precursors shows no evidence of split reflections near the 660-km discontinuity, but potential majorite-ilmenite (590-640 km) and ilmenite-perovskite transitions (740-750 km) are identified based on similarly processed high-frequency P'P' precursors. At nominal mantle temperatures these two phase changes may be seismically indistinguishable, but colder mantle conditions from the descending Nazca plate, the presence of water and variable Fe contents may cause sufficient separation for a reliable analysis. In addition, our preliminary results provide compelling evidence for multiple shallow lower-mantle reflections (at ~800 km) along the elongated plate boundary zones of South America. Slab stagnation at the base of the transition zone could play a key role, though a proper interpretation of this finding would likely entail compositional (rather than strictly thermal) variations in the vicinity of the descending oceanic crust and lithosphere. Overall, the resolution and sensitivity differences between low/intermediate- S and high-frequency P wave reflections are key considerations toward reconciling seismic and mineralogical models of transition zone structure, both at the study location and worldwide.

Seismic Regionalization of Michoacan, Mexico and Recurrence Periods for Earthquakes

NASA Astrophysics Data System (ADS)

Magaña García, N.; Figueroa-Soto, Á.; Garduño-Monroy, V. H.; Zúñiga, R.

2017-12-01

Michoacán is one of the states with the highest occurrence of earthquakes in Mexico and it is a limit of convergence triggered by the subduction of Cocos plate over the North American plate, located in the zone of the Pacific Ocean of our country, in addition to the existence of active faults inside of the state like the Morelia-Acambay Fault System (MAFS).It is important to make a combination of seismic, paleosismological and geological studies to have good planning and development of urban complexes to mitigate disasters if destructive earthquakes appear. With statistical seismology it is possible to characterize the degree of seismic activity as well as to estimate the recurrence periods for earthquakes. For this work, seismicity catalog of Michoacán was compiled and homogenized in time and magnitude. This information was obtained from world and national agencies (SSN, CMT, etc), some data published by Mendoza and Martínez-López (2016) and starting from the seismic catalog homogenized by F. R. Zúñiga (Personal communication). From the analysis of the different focal mechanisms reported in the literature and geological studies, the seismic regionalization of the state of Michoacán complemented the one presented by Vázquez-Rosas (2012) and the recurrence periods for earthquakes within the four different seismotectonic regions. In addition, stable periods were determined for the b value of the Gutenberg-Richter (1944) using the Maximum Curvature and EMR (Entire Magnitude Range Method, 2005) techniques, which allowed us to determine recurrence periods: years for earthquakes upper to 7.5 for the subduction zone (A zone) with EMR technique and years with MAXC technique for the same years for earthquakes upper to 5 for B1 zone with EMR technique and years with MAXC technique; years for earthquakes upper to 7.0 for B2 zone with EMR technique and years with MAXC technique; and the last one, the Morelia-Acambay Fault Sistem zone (C zone) years for earthquakes upper to 5 with EMR technique and years with MAXC technique. This recurrence periods are very similar to periods calculated by Garduño-Monroy (2009) and Sunye-Puchol (2015) using paleoseismological methods. If we consider that the MAFS cross Zacapu, Pátzcuaro, Morelia, Cuitzeo, Maravatío and Acambay, the affected population would be around 1132807 habitants.

Review of metamorphic and kinematic data from Internal Crystalline Massifs (Western Alps): PTt paths and exhumation history

NASA Astrophysics Data System (ADS)

Gasco, Ivano; Gattiglio, Marco; Borghi, Alessandro

2013-01-01

Detailed geological mapping combined with micro-structural and petrological investigation allowed to clarify the tectono-metamorphic relationships between continental and oceanic units transition in the Penninic domain of the Western Alps. The three study areas (Gressoney, Orco and Susa sections) take into consideration the same structural level across the axial metamorphic belt of the Western Italian Alps, i.e., a geological section across the Internal Crystalline Massifs vs Piedmont Zone boundary. The units outcropping in these areas can be grouped into two Tectonic Elements according to their tectono-metamorphic evolution. The Lower Tectonic Element (LTE) consists of the Internal Crystalline Massifs and the Lower Piedmont Zone (Zermatt-Saas like units), both showing well preserved eclogite facies relics. Instead, the Upper Tectonic Element (UTE) consists of the Upper Piedmont Zone (Combin like units) lacking evidence of eclogite facies relics. In the Lower Tectonic Element two main Alpine tectono-metamorphic stages were identified: M1/D1 developed under eclogite facies conditions and M2/D2 is related to the development of the regional foliation under greenschist to epidote-albite amphibolite facies conditions. In the Upper Tectonic Element the metamorphic stage M1/D1 developed under bluschist to greenschist facies conditions and M2/D2 stage under greenschist facies conditions. These two Tectonic Elements are separated by a tectonic contact of regional importance generally developed along the boundary between the Lower and the Upper Piedmont zone under greenschist facies conditions. PT data compared to geochronology indicate that the first exhumation of ICM can be explained by buoyancy forces acting along the subduction channel that occurred during the tectonic coupling between the continental and oceanic eclogite units. These buoyancy forces vanished at the base of the crust where the density difference between the subducted crustal units and the surroundings rocks is too low. A stage where compression prevails on the previous exhumation followed, which leads to the development of the regional foliation under greenschist to amphibolite facies metamorphic conditions. Further exhumation occurred after the M2/D2 stage at shallower crustal levels along conjugated shear zones leading to the development of a composite axial dome consisting of eclogite-bearing continental-oceanic units (ICM and Zermatt-Saas Zones) beneath greenschist ones (Combin Zone).

The response of southern California ecosystems to Younger Dryas-like rapid climate change: Comparison of glacial terminations 1 and 5.

NASA Astrophysics Data System (ADS)

Heusser, L. E.; Hendy, I. L.

2015-12-01

The Younger Dryas is a well-known rapid climatic cooling that interrupted the Marine Isotope Stage (MIS) 1-2 deglacial warming of Termination 1. This cool event has been associated with ice sheet readvance, meridional overturning, circulation changes, and southward movement of the Intertropical Convergence Zone. In Southern California, the Younger Dryas has been associated with cooler SST, low marine productivity, a well-ventilated oxygen minimum zone, and a wetter climate. Similar rapid cooling events have been found at other terminations including Termination 5 at the MIS 11-12 deglaciation (~425 Ka) identified by ice rafting events in the North Atlantic. Here we present new pollen census data from a unique suite of cores taken from the sub-oxic sediments of Santa Barbara Basin (MV0508-15JC, MV0805-20JC, MV0508-33JC, 29JC and 21JC). These short cores, collected on a truncated anticline within SBB, provide the opportunity to examine the response of southern California terrestrial and marine ecosystems to rapid climate change during the MIS 11-12 deglaciation (Termination 5), which is identified by a bioturbated interval within a sequence of laminated sediments. During Termination 1, changes in Southern California precipitation are reflected in pollen- based reconstructions Southern California vegetation. The high precipitation of glacial montane-coniferous assemblages of pine (Pinus) and Juniper (Juniperus/Calocedrus) transitions into interglacial drought, as expresssed by arid oak (Quercus)/chaparral vegetation. The Younger Dryas interrupts the transition as a high-amplitude pulse in pine associated with increased Gramineae (grass). Termination 5 differs, as the high precipitation of glacial montane-coniferous assemblages do not transition into arid oak/chaparral vegetation. However, a Younger Dryas-like rapid climate event was associated with increased pine and grass.

Dental maturational sequence and dental tissue proportions in the early Upper Paleolithic child from Abrigo do Lagar Velho, Portugal

PubMed Central

Bayle, Priscilla; Macchiarelli, Roberto; Trinkaus, Erik; Duarte, Cidália; Mazurier, Arnaud; Zilhão, João

2010-01-01

Neandertals differ from recent and terminal Pleistocene human populations in their patterns of dental development, endostructural (internal structure) organization, and relative tissue proportions. Although significant changes in craniofacial and postcranial morphology have been found between the Middle Paleolithic and earlier Upper Paleolithic modern humans of western Eurasia and the terminal Pleistocene and Holocene inhabitants of the same region, most studies of dental maturation and structural morphology have compared Neandertals only to later Holocene humans. To assess whether earlier modern humans contrasted with later modern populations and possibly approached the Neandertal pattern, we used high-resolution microtomography to analyze the remarkably complete mixed dentition of the early Upper Paleolithic (Gravettian) child from Abrigo do Lagar Velho, Portugal, and compared it to a Neandertal sample, the late Upper Paleolithic (Magdalenian) child of La Madeleine, and a worldwide extant human sample. Some aspects of the dental maturational pattern and tooth endostructural organization of Lagar Velho 1 are absent from extant populations and the Magdalenian specimen and are currently documented only among Neandertals. Therefore, a simple Neandertal versus modern human dichotomy is inadequate to accommodate the morphostructural and developmental variation represented by Middle Paleolithic and earlier Upper Paleolithic populations. These data reinforce the complex nature of Neandertal-modern human similarities and differences, and document ongoing human evolution after the global establishment of modern human morphology. PMID:20080622

Taxonomic and compositional differences of ground-dwelling arthropods in riparian habitats in Glen Canyon, Arizona, USA

USGS Publications Warehouse

Ralston, Barbara; Cobb, Neil S.; Brantley, Sandra L.; Higgins, Jacob; Yackulic, Charles B.

2017-01-01

The disturbance history, plant species composition, productivity, and structural complexity of a site can exert bottom-up controls on arthropod diversity, abundance, and trophic structure. Regulation alters the hydrology and disturbance regimes of rivers and affects riparian habitats by changing plant quality parameters. Fifty years of regulation along the Colorado River downstream of Glen Canyon Dam has created a no-analog, postdam “lower” riparian zone close to the water's edge that includes tamarisk (Tamarix sp.), a nonnative riparian shrub. At the same time, the predam “upper” facultative riparian zone has persisted several meters above the current flood stage. In summer 2009, we used pitfall traps within these 2 riparian zones that differ in plant composition, productivity, and disturbance frequency to test for differences in arthropod community (Hymenoptera, Arachnida, and Coleoptera) structure. Arthropod community structure differed substantially between the 2 zones. Arthropod abundance and species richness was highest in the predam upper riparian zone, even though there was a greater amount of standing plant biomass in the postdam lower riparian zone. Omnivore abundance was proportionately greater in the upper riparian zone and was associated with lower estimated productivity values. Predators and detritivores were proportionately greater in the postdam lower riparian zone. In this case, river regulation may create habitats that support species of spiders and carabid beetles, but few other species that are exclusive to this zone. The combined richness found in both zones suggests a small increase in total richness and functional diversity for the Glen Canyon reach of the Colorado River.

Geohydrology and potential for upward movement of saline water in the Cocoa well field, East Orange County, Florida

USGS Publications Warehouse

Phelps, G.G.; Schiffer, D.M.

1996-01-01

The Floridan aquifer system, an approximately 2,000-foot thick sequence of Eocene-age limestone and dolomite, is the main source of water supply in central Florida. Hydraulic conductivity is different in strata of different lithology and is the basis for separating the aquifer system into the Upper Floridan aquifer, a middle semi- confining unit, and the Lower Floridan aquifer. The coastal city of Cocoa withdraws about 26 million gallons of water per day from the Upper Floridan aquifer from a well field in east Orange County, about 25 miles inland. About 60 million gallons per day are withdrawn from the Upper Floridan aquifer and 56 million gallons per day from the Lower Floridan aquifer in the Orlando area, about 15 miles west of the Cocoa well field. Wells drilled in the Cocoa well field from 1955-61 yielded water with chloride concentrations ranging from 25-55 milligrams per liter. Soon after the wells were put in service, chloride concentrations increased; therefore, new wells were drilled further inland. Chloride concen- trations in water from many of the new wells also have increased. Possible sources of saline water are lateral movement of relict seawater in the Upper Floridan aquifer from the east, regional upconing of saline water from the Lower Floridan aquifer or underlying older rocks, or localized upward movement of saline water through fractures. Several test wells were drilled to provide information about chloride concentration changes with depth and to monitor changes with time, including a multi-zone well drilled in 1965 (well C) and two wells drilled in the 1990's (wells R and S). Chloride concentrations have increased in the zone pumped by the supply wells (the upper 500 feet of the aquifer) and in the 1,351-1,357-foot deep zone of well C, but not in the two intervening zones. This indicates that the source of saline water is located laterally, rather than vertically, from the pumped zone in the area of well C. The potential for upward movement of saline water depends on the direction of the vertical hydraulic gradient and on the vertical hydraulic conductivity of the aquifer. A series of aquifer tests was run in 1993-94 and existing water-level and water-quality data were analyzed to evaluate the potential for upward movement of saline water in the well field. The transmissivity of the upper 500 feet of the aquifer is about 100,000 feet squared per day (the horizontal hydraulic conductivity is about 200 feet per day) and the storage coefficient is about 2x10 -4. Horizontal hydraulic conductivities determined from slug tests of the three deepest zones of well C ranged from 20-50 feet per day. Vertical hydraulic conductivities probably do not exceed 0.05 feet per day. The vertical hydraulic gradient is determined by comparing water levels in the various zones, but because of density differences, unadjusted water levels in the deepest zone investigated cannot be directly compared to water levels in the overlying freshwater zones. The difference between environmental-water heads (adjusted for density differences) in the saline-water zone of well C and the overlying freshwater zone were calculated from measured water levels for the period 1966 to 1994. During most of this time period, the gradient was downward, indicating that saline water did not move upward. Upconing of saline water probably is not taking place in the center and western part of the well field, based on the low vertical hydraulic conductivity values estimated for the middle semi-confining unit, the generally downward vertical hydraulic gradient, and the constant chloride concentrations in the intermediate zones of well C. However, there is no information about the extent of the zone of low vertical hydraulic conductivity gradient in the eastern part of the well field. Thus, increased chloride concentrations in supply wells in the eastern part of the well field could be caused either by lateral movement of saline water from the east, or by upwar

Simulation of ground-water flow and stream-aquifer relations in the vicinity of the Savannah River Site, Georgia and South Carolina, predevelopment through 1992

USGS Publications Warehouse

Clarke, John S.; West, Christopher T.

1998-01-01

Ground-water flow and stream-aquifer relations were simulated for seven aquifers in Coastal Plain sediments in the vicinity of the U.S. Department of Energy, Savannah River Site (SRS), in Georgia and South Carolina to evaluate the potential for ground water containing hazardous materials to migrate from the SRS into Georgia through aquifers underlying the Savannah River (trans-river flow). The work was completed as part of a cooperative study between the U.S. Geological Survey, the U.S. Department of Energy, and Georgia Department of Natural Resources. The U.S. Geological Survey three-dimensional finite-difference ground-water flow model, MODFLOW, was used to simulate ground-water flow in three aquifer systems containing seven discrete aquifers: (1) the Floridan aquifer system, consisting of the Upper Three Runs and Gordon aquifers in sediments of Eocene age; (2) the Dublin aquifer system, consisting of the Millers Pond, and upper and lower Dublin aquifers in sediments of Paleocene and Late Cretaceous age; and (3) the Midville aquifer system, consisting of the upper and lower Midville aquifers of sediments in Late Cretaceous age. Ground-water flow was simulated using a series of steady-state simulations of predevelopment (pre-1953) conditions and six pumping periods--1953-60, 1961-70, 1971-75, 1976-80, 1981-86, and 1987-92--results are presented for predevelopment (prior to 1953) and modern-day (1987-92) conditions. Total simulated predevelopment inflow is 1,023 million gallons per day (Mgal/d), of which 76 percent is contributed by leakage from the Upper Three Runs aquifer. Over most of the study area, pumpage induced changes in ground-water levels, ground-water discharge to streams, and water-budget components were small during 1953-92, and changes in aquifer storage were insignificant. Simulated drawdown between predevelopment and modern-day conditions is small (less than 7 feet) and of limited areal extent--the largest simulated declines occur in the upper and lower Dublin aquifers in the vicinity of the Sandoz plant site in South Carolina. These declines extend beneath the Savannah River and change the configuration of the simulated potentiometric surface and flow paths near the river. Predevelopment and modern-day flowpaths were simulated near the Savannah River by using the U.S. Geological Survey particle-tracking code MODPATH. Eastward and westward zones of trans-river flow were identified in three principal areas as follows: --zone 1-from the Fall Line southward to the confluence of Hollow Creek and the Savannah River; --zone 2-from the zone 1 boundary southward to the southern border of the SRS (not including the Lower Three Runs Creek section); and --zone 3-from the zone 2 boundary, southward into the northern part of Screven County, Ga. All zones for all model layers were located within or immediately adjacent to the Savannah River alluvial valley and most were located in the immediate vicinity of the Savannah River. Recharge areas for each of the zones of trans-river flow generally are in the vicinity of major interstream drainage divides. Mean time-of-travel simulated for predevelopment conditions ranges from 300 to 24,000 years for westward trans-river flow zones; and from 550 to 41,000 years for eastward zones. Corresponding travel times under modern-day conditions range from 300 to 34,000 years for westward zones and from 580 to 31,000 years for eastward zones. Differences in travel times between predevelopment and modern-day simulations result from changes in hydraulic gradients due to ground-water pumpage that alter flow paths in the vicinity of the river. Recharge to Georgia trans-river flow zones originating on the SRS was simulated for the Gordon and upper Dublin aquifers during predevelopment, and in the Gordon aquifer during 1987-92. During 1987-92, SRS recharge was simulated in 6 model cells covering a 2-square mile area, located away from areas of ground-water contamination. Si

15 CFR 923.82 - Amendment review/approval procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... (Continued) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved...

15 CFR 923.82 - Amendment review/approval procedures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... (Continued) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved...

77 FR 44472 - Safety Zone; Port Valdez, Alaska Maritime Highway System Ferry Terminal

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

... Game, which does not afford time for public feedback on a safety zone that will be in effect only when... month of July, the Alaska Department of Fish and Game has announced fishing openers in the Port of... an Alaska Department of Fish and Game fish opener that includes the 200-yard radius surrounding the...

[Study of the intracerebral connections after intracortical administration of glutamate].

PubMed

Otellin, V A; Rybakov, V L; Grigor'ev, I P

1980-10-01

Various microdoses of monosubstituted sodium L-glutamate (MSG) were injected into zone AI of the cat cerebral acoustic cortex. In 2 h--14 days, it was stated light optically that the place of injection was slightly stained, and most of neurons failed to stain. At the place of MSG injection, electron microscopic investigation revealed neurons with various degree of pathologic changes up to the lethal ones. Astroglia was edematous, oligodendrocytes and pericytes had normal appearance. In field 4 and in zone AII of the acoustic cortex, separate neural cells with sharply increasing number of ribosomes and polysomes were noted. Anterograde axonal degeneration in the lesioned neurons and their terminals was revealed in frontal sections impregnated after Wiitanen. In the cortical field 7, in zones AII, AIV, Ep of the acoustic cortex, in the head of the nucleus caudatus and in the internal geniculate body, terminal boutons degenerating after the dark type and at the same time as after surgical extirpation of zone AI were revealed. Owing to the fact that the lesions are of local character and the trauma is small, it is possible to use neuronal glutamate-induced degeneration as a method for investigating intracerebral connections.

Electrical resistivity and porosity structure of the upper Biscayne Aquifer in Miami-Dade County, Florida

NASA Astrophysics Data System (ADS)

Whitman, Dean; Yeboah-Forson, Albert

2015-12-01

Square array electrical soundings were made at 13 sites in the Biscayne Aquifer distributed between 1 and 20 km from the shoreline. These soundings were modeled to investigate how resistivity varies spatially and with depth in the upper 15 m of the aquifer. Porosity was estimated from the modeled formation resistivity and observed pore fluid resistivity with Archie's Law. The models were used to interpolate resistivity and porosity surfaces at -2, -5, -8, and -15 m elevations. Modeled resistivity in the unsaturated zone is generally higher than 300 Ω m with the resistivity at sites with thick unsaturated zones greater than 1000 Ω m. Resistivity in the saturated zone ranges from 30 to 320 Ω m. At many sites in the western portions of the study area, resistivity is constant or increases with depth whereas sites in the center of the Atlantic Coastal Ridge exhibit a distinct low resistivity zone (ρ < 45 Ω m) at elevations ranging between -5 and -10 m. At one site near the shore of Biscayne Bay, the resistivity is less than 10 Ω m at -5 m elevation reflecting the presence of salt water in the aquifer. The estimated porosity ranges between 14% and 71% with modal values near 25%. The porosity structure varies both with depth and spatially. Western sites exhibit a high porosity zone at shallow depths best expressed in a NE-SW trending zone of 40-50% porosity situated near the western margin of the Atlantic Coastal Ridge. This zone roughly corresponds in depth with the Q5 chronostratigraphic unit of the Miami Fm. which constitutes the upper flow unit of the Biscayne Aquifer. The highest porosity (>50%) is seen at elevations below -5 m at sites in the center of the Atlantic Coastal Ridge and likely corresponds to solution features. The general NE-SW trend of the resistivity and porosity structure suggests a causal connection with the Pleistocene paleogeography and sedimentary environments.

Seismic tomography shows that upwelling beneath Iceland is confined to the upper mantle

USGS Publications Warehouse

Foulger, G.R.; Pritchard, M.J.; Julian, B.R.; Evans, J.R.; Allen, R.M.; Nolet, G.; Morgan, W.J.; Bergsson, B.H.; Erlendsson, P.; Jakobsdottir, S.; Ragnarsson, S.; Stefansson, R.; Vogfjord, K.

2001-01-01

We report the results of the highest-resolution teleseismic tomography study yet performed of the upper mantle beneath Iceland. The experiment used data gathered by the Iceland Hotspot Project, which operated a 35-station network of continuously recording, digital, broad-band seismometers over all of Iceland 1996-1998. The structure of the upper mantle was determined using the ACH damped least-squares method and involved 42 stations, 3159 P-wave, and 1338 S-wave arrival times, including the phases P, pP, sP, PP, SP, PcP, PKIKP, pPKIKP, S, sS, SS, SKS and Sdiff. Artefacts, both perceptual and parametric, were minimized by well-tested smoothing techniques involving layer thinning and offset-and-averaging. Resolution is good beneath most of Iceland from ??? 60 km depth to a maximum of ??? 450 km depth and beneath the Tjornes Fracture Zone and near-shore parts of the Reykjanes ridge. The results reveal a coherent, negative wave-speed anomaly with a diameter of 200-250 km and anomalies in P-wave speed, Vp, as strong as -2.7 per cent and in S-wave speed, Vs, as strong as -4.9 per cent. The anomaly extends from the surface to the limit of good resolution at ??? 450 km depth. In the upper ??? 250 km it is centred beneath the eastern part of the Middle Volcanic Zone, coincident with the centre of the ??? 100 mGal Bouguer gravity low over Iceland, and a lower crustal low-velocity zone identified by receiver functions. This is probably the true centre of the Iceland hotspot. In the upper ??? 200 km, the low-wave-speed body extends along the Reykjanes ridge but is sharply truncated beneath the Tjornes Fracture Zone. This suggests that material may flow unimpeded along the Reykjanes ridge from beneath Iceland but is blocked beneath the Tjornes Fracture Zone. The magnitudes of the Vp, Vs and Vp/Vs anomalies cannot be explained by elevated temperature alone, but favour a model of maximum temperature anomalies <200 K, along with up to ??? 2 per cent of partial melt in the depth range ??? 100-300 km beneath east-central Iceland. The anomalous body is approximately cylindrical in the top 250 km but tabular in shape at greater depth, elongated north-south and generally underlying the spreading plate boundary. Such a morphological change and its relationship to surface rift zones are predicted to occur in convective upwellings driven by basal heating, passive upwelling in response to plate separation and lateral temperature gradients. Although we cannot resolve structure deeper than ??? 450 km, and do not detect a bottom to the anomaly, these models suggest that it extends no deeper than the mantle transition zone. Such models thus suggest a shallow origin for the Iceland hotspot rather than a deep mantle plume, and imply that the hotspot has been located on the spreading ridge in the centre of the north Atlantic for its entire history, and is not fixed relative to other Atlantic hotspots. The results are consistent with recent, regional full-thickness mantle tomography and whole-mantle tomography images that show a strong, low-wave-speed anomaly beneath the Iceland region that is confined to the upper mantle and thus do not require a plume in the lower mantle. Seismic and geochemical observations that are interpreted as indicating a lower mantle, or core-mantle boundary origin for the North Atlantic Igneous Province and the Iceland hotspot should be re-examined to consider whether they are consistent with upper mantle processes.

78 FR 45871 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... components: Hydrogeologic study; Surface water sampling study; Stream biological study; Air quality survey... components: Biological survey; Biota survey; Surface water and sediment characterization; Groundwater... impacted groundwater in three water bearing zones at the Site; the unconsolidated materials zone, the upper...

75 FR 66083 - Iron Mask Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-27

... following: (1) A 225-foot- high, 1,795-foot-long upper dam made of either zoned earth and rockfill or concrete-face earth and rockfill; (2) a 50-foot-high, 950-foot-long earth-filled upper saddle dike A; (3) a 20-foot-high, 400-foot-long earth-filled upper saddle dike B; (4) a 40-foot-high, 6,559-foot-long...

NUSTAR AND XMM-Newton Observations of the Neutron Star X-Ray Binary 1RXS J180408.9-34205

NASA Astrophysics Data System (ADS)

Ludlam, Renee; Miller, Jon M.; Cackett, Edward; Fabian, Andrew C.; Bachetti, Matteo; Parker, Michael; Tomsick, John; Barret, Didier; Natalucci, Lorenzo; Rana, Vikram; Harrison, Fiona

2016-04-01

We report on observations of the neutron star (NS) residing in the low-mass X-ray binary 1RXS J180408.9-34205 taken 2015 March by NuSTAR and XMM-Newton while the source was in the hard spectral state. We findmultiple reflection features (Fe Kα detected with NuSTAR N VII, O VII, and O VIII detected in the RGS) fromdifferent ionization zones. Through joint fits using the self consistent relativistic reflection model RELXILL,we determine the inner radius to be 6.6(+13.2,-0.6) Rg. We find the inclination of the system to be between 18-29 degrees.If the disk is truncated at a radius greater than the innermost stable circular orbit (ISCO), then the position at which the inner disk terminates likely corresponds to the magnetospheric radius. For a spin parameter of a = 0, we estimate a conservative upper limit on the strength of the magnetic field to be B ≤ (0.9 - 3.0) × 109 G at the magnetic poles depending on the choice of conversion factor between spherical and disk accretion.

Microstructural and fabric characterization of brittle-ductile transitional deformation of middle crustal rocks along the Jinzhou detachment fault zone, Northeast China

NASA Astrophysics Data System (ADS)

Zhang, Juyi; Jiang, Hao; Liu, Junlai

2017-04-01

Detachment fault zones (DFZs) of metamorphic core complexes generally root into the middle crust. Exhumed DFZs therefore generally demonstrate structural, microstructural and fabric features characteristic of middle to upper crustal deformation. The Jinzhou detachment fault zone from the Liaonan metamorphic core complex is characterized by the occurrence of a sequence of fault rocks due to progressive shearing along the fault zone during exhumation of the lower plate. From the exhumed fabric zonation, cataclastic rocks formed in the upper crust occur near the Jinzhou master detachment fault, and toward the lower plate gradually changed to mylonites, mylonitic gneisses and migmatitic gneisses. Correspondingly, these fault rocks have various structural, microstructural and fabric characteristics that were formed by different deformation and recrystallization mechanisms from middle to upper crustal levels. At the meanwhile, various structural styles for strain localization were formed in the DFZ. As strain localization occurs, rapid changes in deformation mechanisms are attributed to increases in strain rates or involvement of fluid phases during the brittle-ductile shearing. Optical microscopic studies reveal that deformed quartz aggregates in the lower part of the detachment fault zone are characterized by generation of dynamically recrystallized grains via SGR and BLG recrystallization. Quartz rocks from the upper part of the DFZ have quartz porphyroclasts in a matrix of very fine recrystallized grains. The porphyroclasts have mantles of sub-grains and margins grain boundary bulges. Electron backscattered diffraction technique (EBSD) quartz c-axis fabric analysis suggests that quartz grain aggregates from different parts of the DFZ possess distinct fabric complexities. The c-axis fabrics of deformed quartz aggregates from mylonitic rocks in the lower part of the detachment fault zone preserve Y-maxima which are ascribed to intermediate temperature deformation (500-630˚ C), whereas complicated fabric patterns (e.g. asymmetric single girdles) are formed in fault rocks from the upper part of the DFZ. The increasing fabric complexity is here interpreted as the result of progressive superposition of fault rocks by shearing either at relatively shallow levels or high rate of strain, during exhumation of the lower plate and shear zone rocks. The above observations and interpretations imply that dislocation creep processes contribute to the dynamic recrystallization of quartz in the middle crustal brittle-ductile transition. Progressive shearing as a consequence of exhumation of the lower plate of the MCC contributed to the obvious structural, microstructural and fabric superpositions. Strain localization occurs as the progressive shearing proceeded. Transition of mechanisms of deformation and dynamic recrystallization during strain localization may be resulted from changes in temperature conditions, in strain rates or addition of minor amount water.

FLOW SYSTEM FOR REACTOR

DOEpatents

Zinn, W.H.

1963-06-11

A reactor is designed with means for terminating the reaction when returning coolant is below a predetermined temperature. Coolant flowing from the reactor passes through a heat exchanger to a lower reservoir, and then circulates between the lower reservoir and an upper reservoir before being returned to the reactor. Means responsive to the temperature of the coolant in the return conduit terminate the chain reaction when the temperature reaches a predetermined minimum value. (AEC)

Imaging of upper crustal structure beneath East Java-Bali, Indonesia with ambient noise tomography

NASA Astrophysics Data System (ADS)

Martha, Agustya Adi; Cummins, Phil; Saygin, Erdinc; Sri Widiyantoro; Masturyono

2017-12-01

The complex geological structures in East Java and Bali provide important opportunities for natural resource exploitation, but also harbor perils associated with natural disasters. Such a condition makes the East Java region an important area for exploration of the subsurface seismic wave velocity structure, especially in its upper crust. We employed the ambient noise tomography method to image the upper crustal structure under this study area. We used seismic data recorded at 24 seismographs of BMKG spread over East Java and Bali. In addition, we installed 28 portable seismographs in East Java from April 2013 to January 2014 for 2-8 weeks, and we installed an additional 28 seismographs simultaneously throughout East Java from August 2015 to April 2016. We constructed inter-station Rayleigh wave Green's functions through cross-correlations of the vertical component of seismic noise recordings at 1500 pairs of stations. We used the Neighborhood Algorithm to construct depth profiles of shear wave velocity (Vs). The main result obtained from this study is the thickness of sediment cover. East Java's southern mountain zone is dominated by higher Vs, the Kendeng basin in the center is dominated by very low Vs, and the Rembang zone (to the North of Kendeng zone) is associated with medium Vs. The existence of structures with oil and gas potential in the Kendeng and Rembang zones can be identified by low Vs.

Enhanced East Pacific Rise hydrothermal activity during the last two glacial terminations

NASA Astrophysics Data System (ADS)

Lund, D. C.; Asimow, P. D.; Farley, K. A.; Rooney, T. O.; Seeley, E.; Jackson, E. W.; Durham, Z. M.

2016-01-01

Mid-ocean ridge magmatism is driven by seafloor spreading and decompression melting of the upper mantle. Melt production is apparently modulated by glacial-interglacial changes in sea level, raising the possibility that magmatic flux acts as a negative feedback on ice-sheet size. The timing of melt variability is poorly constrained, however, precluding a clear link between ridge magmatism and Pleistocene climate transitions. Here we present well-dated sedimentary records from the East Pacific Rise that show evidence of enhanced hydrothermal activity during the last two glacial terminations. We suggest that glacial maxima and lowering of sea level caused anomalous melting in the upper mantle and that the subsequent magmatic anomalies promoted deglaciation through the release of mantle heat and carbon at mid-ocean ridges.

Lower paleozoic of Baltic Area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haselton, T.M.; Surlyk, F.

The Baltic Sea offers a new and exciting petroleum play in northwestern Europe. The Kaliningrad province in the Soviet Union, which borders the Baltic Sea to the east, contains an estimated 3.5 billion bbl of recoverable oil from lower Paleozoic sandstones. To the south, in Poland, oil and gas fields are present along a trend that projects offshore into the Baltic. Two recent Petrobaltic wells in the southern Baltic have tested hydrocarbons from lower Paleozoic sandstone. Minor production comes from Ordovician reefs on the Swedish island of Gotland in the western Baltic. The Baltic synclise, which began subsiding in themore » late Precambrian, is a depression in the East European platform. Strate dip gently to the south where the Baltic Synclise terminates against a structurally complex border zone. Depth to the metamorphosed Precambrian basement is up to 4,000 m. Overlying basement is 200-300 m of upper Precambrian arkosic sandstone. The Lower Cambrian consists of shallow marine quartzites. During Middle and Late Camnbrian, restricted circulation resulted in anoxic conditions and the deposition of Alum shale. The Lower Ordovician consists of quartzites and shale. The Upper Ordovician includes sandstones and algal reefs. The Silurian contains marginal carbonates and shales. For the last 25 years, exploration in northwest Europe has concentrated on well-known Permian sandstone, Jurassic sandstone, and Cretaceous chalk plays. Extrapolation of trends known and exploited in eastern Europe could open an entirely new oil province in the lower Paleozoic in the Baltic.« less

Preliminary study on the L ate Cretaceous ostracods from continental scientific drilling SK1 in the Songliao Basin, NE China

NASA Astrophysics Data System (ADS)

Xi, Dangpeng; Qu, Haiying; Shi, Zhongye; Wan, Xiaoqiao

2017-04-01

Songliao Basin is one of the biggest lacustrine systems in Asia during Cretaceous age. Widespread deposits in the basin are mainly composed of clastic sediments which contain abundant fossils including gastropod, bivalves, ostracods, vertebrates and others. These well preserved ostracod fossils provide us valuable information about past climate changes and biotic responses in a greenhouse environment.The Cretaceous Continental Scientific Drilling in the Songliao Basin (SK1) offers a rare opportunity to study Late Cretaceous non-marine ostracod. The SK1 was drilled separately in two boreholes: the lower 959.55-meter-thick south core (SK1(s)), and the upper 1636.72-meter-thick north core (SK1 (n)), containing the Upper Quantou, Qingshankou, Yaojia, Nenjiang Formation, Sifangtai, Mingshui and lower Taikang formations. Here we establish high-resolution non-marine ostracod biostratigraphy based on SK1. 80 species belonging to 12 genera in the SK1(S) and 45 species assigned to 20 genera in the SK1(n) have been recovered. Nineteen ostracod assemblage zones have been recognized: 1. Mongolocypris longicaudata-Cypridea Assemblage Zone, 2.Triangulicypris torsuosus-Triangulicypris torsuosus. nota Assemblage Zone, 3. Cypridea dekhoinensis-Cypridea gibbosa Assemblage Zone, 4.Cypridea nota-Sunliavia tumida Assemblage Zone, 5.Cypridea edentula-Lycopterocypris grandis Assemblage Zone, 6.Cypridea fuyuensis-Triangulicypris symmetrica Assemblage Zone, 7.Triangulicypris vestilus-Triangulicypris fusiformis-Triangulicypris pumilis Assemblage Zone, 8.Cypridea panda-Mongolocypris obscura Assemblage Zone, 9. Cypridea exornata-Cypridea dongfangensis Assemblage Zone, 10.Cypridea favosa-Mongolocypris tabulata Assemblage Zone, 11.Cypridea formosa-Cypridea sunghuajiangensis Assemblage Zone, 12. Cypridea anonyma-Candona fabiforma Assemblage Zone, 13.Cypridea gracila-Cypridea gunsulinensis Assemblage Zone, 14.Mongolocypris magna-Mongolocypris heiluntszianensis Assemblage Zone, 15.Cypridea liaukhenensis-Cypridea stellata Assemblage Zone, 16. Ilyocyprimorpha-Limnocypridea sunliaonensis-Periacanthella Assemblage Zone, 17. Strumosia inandita Asemblage-Zone, 18.Talicypridea amoena-Metacypris kaitunensis-Ziziphocypris simakovi Assemblage Zone, 19.Ilyocypris Assemblage Zone. Assemblage Zone 1 to 18 are belong to late Cretaceous, but 19 might constrained to the Latest Maastrichtian to the Earliset Danian.

The Kramer deposit of southern California--Preliminary insights on the origins of zoned lacustrine evaporite borate deposits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swihart, G.H.; McBay, E.H.; Smith, D.H.

1992-01-01

Lacustrine evaporite borate deposits span the range from mineralogically unzoned or poorly zoned to concentrically or complexly zoned types. Deposits often contain an inner ulexite or probertite (Na-Ca borates) zone and an outer colemanite (Ca borate) zone. A few deposits contain an innermost borax (Na borate) zone. Boron isotopic analyses of core material from the zoned borax-ulexite-colemanite Kramer deposit have been made with the aim of providing a better understanding of the processes of zone formation. Samples from 6 depths over a 63 foot interval in the borax zone yield a [delta] B-11 range of +0.1 to +2.3 permil. Twomore » samples in the portion of the ulexite zone below the borax zone, vertically separated from one another by 20 feet, yield identical results of [delta]B-11 = [minus]2.1 permit. Three ulexite samples from a 10 foot interval above the borax zone produced results in the range [delta]B-11 = [minus]4.6 to [minus]5.5 permil. A number of possible origins for ulexite at Kramer have been proposed: (1) primary precipitation from the lake brines; (2) postdepositional alteration of the borax zone margin by Ca-rich groundwater; (3) mixing of seeping lake brines and Ca-rich groundwater in muds around the lake. Given the small variation in B isotopic composition exhibited in the borax zone, mechanisms 1 and 2 would produce upper and lower portions of the ulexite zone with similar isotopic compositions. In the third scenario, the difference in composition of the upper and lower ulexites could be due to distance from the lake and relative proportions of seeped lake brine (B-11-rich) and clay adsorbed B (B-10-rich). Furthermore, the cotton ball form of the ulexite in this core is identical to that of ulexite forming today just beneath the surface of dry lakes in NV and CA.« less

Litho-kinematic facies model for large landslide deposits in arid settings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yarnold, J.C.; Lombard, J.P.

1989-04-01

Reconnaissance field studies of six large landslide deposits in the S. Basin and Range suggest that a set of characteristic features is common to the deposits of large landslides in an arid setting. These include a coarse boulder cap, an upper massive zone, a lower disrupted zone, and a mixed zone overlying disturbed substrate. The upper massive zone is dominated by crackel breccia. This grades downward into a lower disrupted zone composed of a more matrix-rich breccia that is internally sheared, intruded by clastic dikes, and often contains a cataclasite layer at its base. An underlying discontinuous mixed zone ismore » composed of material from the overlying breccia mixed with material entrained from the underlying substrate. Bedding in the substrate sometimes displays folding and contortion that die out downward. The authors work suggests a spatial zonation of these characteristic features within many landslide deposits. In general, clastic dikes, the basal cataclasite, and folding in the substrate are observed mainly in distal parts of landslides. In most cases, total thickness, thickness of the basal disturbed and mixed zones, and the degree of internal shearing increase distally, whereas maximum clast size commonly decreases distally. Zonation of these features is interpreted to result from kinematics of emplacement that cause generally increased deformation in the distal regions of the landslide.« less

Shear wave reflectivity imaging of the Nazca-South America subduction zone: Stagnant slab in the mantle transition zone?

NASA Astrophysics Data System (ADS)

Contenti, Sean; Gu, Yu Jeffrey; Ökeler, Ahmet; Sacchi, Mauricio D.

2012-01-01

In this study we utilize over 5000 SS waveforms to investigate the high-resolution mantle reflectivity structure down to 1200 km beneath the South American convergent margin. Our results indicate that the dynamics of the Nazca subduction are more complex than previously suggested. The 410- and 660-km seismic discontinuities beneath the Pacific Ocean and Amazonian Shield exhibit limited lateral depth variations, but their depths vary substantially in the vicinity of the subducting Nazca plate. The reflection amplitude of the 410-km discontinuity is greatly diminished in a ˜1300-km wide region in the back-arc of the subducting plate, which is likely associated with a compositional heterogeneity on top of the upper mantle transition zone. The underlying 660-km discontinuity is strongly depressed, showing localized depth and amplitude variations both within and to the east of the Wadati-Benioff zone. The width of this anomalous zone (˜1000 km) far exceeds that of the high-velocity slab structure and suggesting significant slab deformation within the transition zone. The shape of the 660-km discontinuity and the presence of lower mantle reflectivity imply both stagnation and penetration are possible as the descending Nazca slab impinges upon the base of the upper mantle.

Latest Cretaceous and Paleocene extension in SE California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tosdal, R.M.; Conrad, J.E.; Murphy, G.P.

1993-04-01

Two ductile deformations formed the 3.5-km-thick, south dipping American Girl shear zone in the Cargo Muchancho Mountains, SE California. The older event (D1) imprints crystalloblastic fabrics that record contractional strains at midcrustal depths in the Middle( ) and Late Jurassic. The second event (D2) is marked by superposed mylonitic fabrics that are coplanar and colinear with fabrics of D1. Small mylonitic shear zones of D2 cut undeformed rocks in the hanging wall of the American Girl shear zone. Folded sheets of Jurassic granite geneiss and kinematic indicators in mylonites indicative southward directed transport down the present dip of the foliationmore » during D2. [sup 40]Ar/[sup 39]Ar release spectrum on hornblende from undeformed upper-plate monzo-diorite (173 Ma, U-Pb zircon), about 2 km above the top of shear zone has a plateau age of 96.7[+-]0.9 Ma. In contrast, hornblende release spectra from granite gneiss about 200 m below the top of the shear zone and from hornblende gneiss about 3 km below the top of the shear zone are flat and have identical ages. Hornblende from monzodiorite at the base of the upper plate has a more complicated spectrum that is interpreted to indicate a cooling age of 60.4[+-]1.3 Ma.« less

Reproduction in the male honey possum (Tarsipes rostratus: Marsupialia): the epididymis.

PubMed

Cummins, J M; Temple-Smith, P D; Renfree, M B

1986-11-01

The epididymis of the adult honey possum, Tarsipes rostratus, is enclosed by a heavily pigmented tunica vaginalis and lies with the testis in a prominent prepenile scrotum. It is connected to the testis by a single ductus efferentis and is lined by approximately equal numbers of cuboidal ciliated and principal cells. It is unusual for marsupials in having no well-defined compartments or fibrous septae and in having extensive convolutions of the duct only at the caudal flexure. Three principal functional zones (initial, middle, and terminal segments) were identified in the epididymis, based on epithelial type and ultrastructural evidence of sperm maturation. Luminal diameter increases progressively throughout the tract, and epithelial height variations (from about 2 to 20 microns) are greatest in the terminal segment. The epithelium itself is remarkably low (maximum of 21.6 microns) compared with that seen in the epididymis of other mammals. The thickness of the peritubular smooth muscle coat increases close to the junction of the epididymis and ductus deferens. Sperm concentrations were estimated from counts of sperm nuclei and thus can be no more than approximations. The figures are consistent, however, with a rapid increase in concentration in the initial segment, indicating extensive fluid resorption. Sperm concentrations appear to peak in the distal zone of the terminal segment, although sampling problems and wide variations in count make such a conclusion only tentative. Principal and basal cells are the predominant cell types in the epididymal epithelium. Basal cells are most abundant in the initial and distal middle segment. Principal cells show structural evidence of active exchange with the luminal contents and have abundant apical stereocilia, the structure of which depends on the epididymal zone. Other cell types occur less commonly in the epithelium. Lipid-rich and phagocytic principal cells are restricted to the middle and distal zones of the middle segment, respectively. Clear cells, restricted to the terminal segment, and halo cells were found in very low numbers. As in some other marsupials, principal cells (possibly specialized for this function) selectively remove cytoplasmic droplets and probably other cellular debris from the luminal contents. In Tarsipes, however, this process is not very efficient, and many discarded droplets pass through to the terminal segment where they form large masses of debris associated with aggregates of degenerating spermatozoa.

Spatial and temporal changes in microbial community structure associated with recharge-influenced chemical gradients in a contaminated aquifer

USGS Publications Warehouse

Haack, S.K.; Fogarty, L.R.; West, T.G.; Alm, E.W.; McGuire, J.T.; Long, D.T.; Hyndman, D.W.; Forney, L.J.

2004-01-01

In a contaminated water-table aquifer, we related microbial community structure on aquifer sediments to gradients in 24 geochemical and contaminant variables at five depths, under three recharge conditions. Community amplified ribsosomal DNA restriction analysis (ARDRA) using universal 16S rDNA primers and denaturing gradient gel electrophoresis (DGGE) using bacterial 16S rDNA primers indicated: (i) communities in the anoxic, contaminated central zone were similar regardless of recharge; (ii) after recharge, communities at greatest depth were similar to those in uncontaminated zones; and (iii) after extended lack of recharge, communities at upper and lower aquifer margins differed from communities at the same depths on other dates. General aquifer geochemistry was as important as contaminant or terminal electron accepting process (TEAP) chemistry in discriminant analysis of community groups. The Shannon index of diversity (H) and the evenness index (E), based on DGGE operational taxonomic units (OTUs), were statistically different across community groups and aquifer depths. Archaea or sulphate-reducing bacteria 16S rRNA abundance was not clearly correlated with TEAP chemistry indicative of methanogenesis or sulphate reduction. Eukarya rRNA abundance varied by depth and date from 0 to 13% of the microbial community. This contaminated aquifer is a dynamic ecosystem, with complex interactions between physical, chemical and biotic components, which should be considered in the interpretation of aquifer geochemistry and in the development of conceptual or predictive models for natural attenuation or remediation.

A customized gene expression microarray reveals that the brittle stem phenotype fs2 of barley is attributable to a retroelement in the HvCesA4 cellulose synthase gene.

PubMed

Burton, Rachel A; Ma, Gang; Baumann, Ute; Harvey, Andrew J; Shirley, Neil J; Taylor, Jillian; Pettolino, Filomena; Bacic, Antony; Beatty, Mary; Simmons, Carl R; Dhugga, Kanwarpal S; Rafalski, J Antoni; Tingey, Scott V; Fincher, Geoffrey B

2010-08-01

The barley (Hordeum vulgare) brittle stem mutants, fs2, designated X054 and M245, have reduced levels of crystalline cellulose compared with their parental lines Ohichi and Shiroseto. A custom-designed microarray, based on long oligonucleotide technology and including genes involved in cell wall metabolism, revealed that transcript levels of very few genes were altered in the elongation zone of stem internodes, but these included a marked decrease in mRNA for the HvCesA4 cellulose synthase gene of both mutants. In contrast, the abundance of several hundred transcripts changed in the upper, maturation zones of stem internodes, which presumably reflected pleiotropic responses to a weakened cell wall that resulted from the primary genetic lesion. Sequencing of the HvCesA4 genes revealed the presence of a 964-bp solo long terminal repeat of a Copia-like retroelement in the first intron of the HvCesA4 genes of both mutant lines. The retroelement appears to interfere with transcription of the HvCesA4 gene or with processing of the mRNA, and this is likely to account for the lower crystalline cellulose content and lower stem strength of the mutants. The HvCesA4 gene maps to a position on chromosome 1H of barley that coincides with the previously reported position of fs2.

A Customized Gene Expression Microarray Reveals That the Brittle Stem Phenotype fs2 of Barley Is Attributable to a Retroelement in the HvCesA4 Cellulose Synthase Gene1[W][OA

PubMed Central

Burton, Rachel A.; Ma, Gang; Baumann, Ute; Harvey, Andrew J.; Shirley, Neil J.; Taylor, Jillian; Pettolino, Filomena; Bacic, Antony; Beatty, Mary; Simmons, Carl R.; Dhugga, Kanwarpal S.; Rafalski, J. Antoni; Tingey, Scott V.; Fincher, Geoffrey B.

2010-01-01

The barley (Hordeum vulgare) brittle stem mutants, fs2, designated X054 and M245, have reduced levels of crystalline cellulose compared with their parental lines Ohichi and Shiroseto. A custom-designed microarray, based on long oligonucleotide technology and including genes involved in cell wall metabolism, revealed that transcript levels of very few genes were altered in the elongation zone of stem internodes, but these included a marked decrease in mRNA for the HvCesA4 cellulose synthase gene of both mutants. In contrast, the abundance of several hundred transcripts changed in the upper, maturation zones of stem internodes, which presumably reflected pleiotropic responses to a weakened cell wall that resulted from the primary genetic lesion. Sequencing of the HvCesA4 genes revealed the presence of a 964-bp solo long terminal repeat of a Copia-like retroelement in the first intron of the HvCesA4 genes of both mutant lines. The retroelement appears to interfere with transcription of the HvCesA4 gene or with processing of the mRNA, and this is likely to account for the lower crystalline cellulose content and lower stem strength of the mutants. The HvCesA4 gene maps to a position on chromosome 1H of barley that coincides with the previously reported position of fs2. PMID:20530215

Absolute geostrophic currents over the SR02 section south of Africa in December 2009

NASA Astrophysics Data System (ADS)

Tarakanov, Roman

2017-04-01

The structure of the absolute geostrophic currents is investigated on the basis of CTD-, SADCP- and LADCP-data over the hydrographic section occupied south of Africa from the Good Hope Cape to 57° S along the Prime Meridian, and on the basis of satellite data on absolute dynamic topography (ADT) produced by Ssalto/Duacs and distributed by Aviso, with a support from Cnes (http://www.aviso.altimetry.fr/duacs/). Thus the section crossed the subtropical zone (at the junction of the subtropical gyres of the Indian and Atlantic oceans), the Antarctic Circumpolar Current (ACC) and terminated at the northern periphery of the Weddell Gyre. A total of 87 stations were occupied here with CTD-, and LADCP-profiling in the entire water column. The distance between stations was 20 nautical miles. Absolute geostrophic currents were calculated between each pair of CTD-stations with barotropic correction based on two methods: by SADCP data and by ADT at these stations. The subtropical part of the section crossed a large segment of the Agulhas meander, already separated from the current and disintegrating into individual eddies. In addition, smaller formed cyclones and anticyclones of the Agulhas Current were also observed in this zone. These structural elements of the upper layer of the ocean currents do not penetrate deeper than 1000-1500 m. Oppositely directed barotropic currents with velocities up to 30 cm/s were observed below these depths extending to the ocean bottom. Such large velocities agree well with the data of the bottom tracking of Lowered ADCP. Only these data were the reliable results of LADCP measurements because of the high transparency of the deep waters of the subtropical zone. The total transport of absolute geostrophic currents in the section is estimated as 144 and 179 Sv to the east, based on the SADCP and ADT barotropic correction, respectively. A transport of 4 (2) Sv to the east was observed on the northern periphery of the Weddell Gyre, 187 (182) Sv to the east was in the ACC zone (up to Subtropical front), 47 (5) Sv to the west was in the subtropical zone. The total transport of abyssal barotropic currents in the subtropical zone was 18 to the west (7 to the east).

Diagnostic heavy minerals in Plio-Pleistocene sediments of the Yangtze Coast, China with special reference to the Yangtze River connection into the sea

NASA Astrophysics Data System (ADS)

Chen, Jing; Wang, Zhanghua; Chen, Zhongyuan; Wei, Zixin; Wei, Taoyuan; Wei, Wei

2009-12-01

This present study revealed five heavy mineral zones in the Yangtze coastal borehole sediments. Ilmenite, garnet and zircon suite of Zone I of the Pliocene characterizes the derivation of basaltic bedrock and local andesitic-granitic rocks. Indicative limonite in the Zone I sediments formed as alluvial fan facies shows strong chemical weathering. The assemblage of amphibole, straurolite, kyanite and idocrase of metamorphic derivation, together with a few zircon and tourmaline of andesitic-granitic origin in Zone II, represents the extension of sediment sources to the lower and middle Yangtze basin in Early Pleistocene as the study area subsided. Also, the braided to meandering riverine facies demonstrates a longer distance sediment transport. Few heavy minerals remained in Zone III of Mid-Pleistocene, when mottled thicker stiff mud occurred as the lacustrine facies, suggesting a quasi-coastal floodplain with lower capability of sediment transport. Heavy minerals appeared significant and continuous in Zone IV of Late Pleistocene, when changing to the shallow marine facies, inferring much extended sediment sources to the upper Yangtze. Hypersthene, identified primarily in Zone IV, was closely associated with the Er-Mei Mountain tholeiite basalt of the upper Yangtze. Heavy minerals of Zone V remained almost the same as IV during Holocene, when the modern delta evolved. The heavy minerals suggested the timing of the Yangtze connection to the sea at ca 0.12 Ma BP.

Depositional sequence stratigraphy and architecture of the cretaceous ferron sandstone: Implications for coal and coalbed methane resources - A field excursion

USGS Publications Warehouse

Garrison, J.R.; Van Den, Bergh; Barker, C.E.; Tabet, D.E.

1997-01-01

This Field Excursion will visit outcrops of the fluvial-deltaic Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale, known as the Last Chance delta or Upper Ferron Sandstone. This field guide and the field stops will outline the architecture and depositional sequence stratigraphy of the Upper Ferron Sandstone clastic wedge and explore the stratigraphic positions and compositions of major coal zones. The implications of the architecture and stratigraphy of the Ferron fluvial-deltaic complex for coal and coalbed methane resources will be discussed. Early works suggested that the southwesterly derived deltaic deposits of the the upper Ferron Sandstone clastic wedge were a Type-2 third-order depositional sequence, informally called the Ferron Sequence. These works suggested that the Ferron Sequence is separated by a type-2 sequence boundary from the underlying 3rd-order Hyatti Sequence, which has its sediment source from the northwest. Within the 3rd-order depositional sequence, the deltaic events of the Ferron clastic wedge, recognized as parasequence sets, appear to be stacked into progradational, aggradational, and retrogradational patterns reflecting a generally decreasing sediment supply during an overall slow sea-level rise. The architecture of both near-marine facies and non-marine fluvial facies exhibit well defined trends in response to this decrease in available sediment. Recent studies have concluded that, unless coincident with a depositional sequence boundary, regionally extensive coal zones occur at the tops of the parasequence sets within the Ferron clastic wedge. These coal zones consist of coal seams and their laterally equivalent fissile carbonaceous shales, mudstones, and siltstones, paleosols, and flood plain mudstones. Although the compositions of coal zones vary along depositional dip, the presence of these laterally extensive stratigraphic horizons, above parasequence sets, provides a means of correlating and defining the tops of depositional parasequence sets in both near-marine and non-marine parts of fluvial-deltaic depositional sequences. Ongoing field studies, based on this concept of coal zone stratigraphy, and detailed stratigraphic mapping, have documented the existence of at least 12 parasequence sets within the Last Chance delta clastic wedge. These parasequence sets appear to form four high frequency, 4th-order depositional sequences. The dramatic erosional unconformities, associated with these 4th-order sequence boundaries, indicate that there was up to 20-30 m of erosion, signifying locally substantial base-level drops. These base-level drops were accompanied by a basin ward shift in paleo-shorelines by as much as 5-7 km. These 4th-order Upper Ferron Sequences are superimposed on the 3rd-order sea-level rise event and the 3rd-order, sediment supply/accommodation space driven, stratigraphie architecture of the Upper Ferron Sandstone. The fluvial deltaic architecture shows little response to these 4th-order sea-level events. Coal zones generally thicken landward relative to the mean position of the landward pinch-out of the underlying parasequence set, but after some distance landward, they decrease in thickness. Coal zones also generally thin seaward relative to the mean position of the landward pinch-out of the underlying parasequence set. The coal is thickest in the region between this landward pinch-out and the position of maximum zone thickness. Data indicate that the proportion of coal in the coal zone decreases progressively landward from the landward pinch-out. The effects of differential compaction and differences in original pre-peat swamp topography have the effect of adding perturbations to the general trends. These coal zone systematics have major impact on approaches to exploration and production, and the resource accessment of both coal and coalbed methane.

3D mapping, hydrodynamics and modelling of the freshwater-brine mixing zone in salt flats similar to the Salar de Atacama (Chile)

NASA Astrophysics Data System (ADS)

Marazuela, M. A.; Vázquez-Suñé, E.; Custodio, E.; Palma, T.; García-Gil, A.; Ayora, C.

2018-06-01

Salt flat brines are a major source of minerals and especially lithium. Moreover, valuable wetlands with delicate ecologies are also commonly present at the margins of salt flats. Therefore, the efficient and sustainable exploitation of the brines they contain requires detailed knowledge about the hydrogeology of the system. A critical issue is the freshwater-brine mixing zone, which develops as a result of the mass balance between the recharged freshwater and the evaporating brine. The complex processes occurring in salt flats require a three-dimensional (3D) approach to assess the mixing zone geometry. In this study, a 3D map of the mixing zone in a salt flat is presented, using the Salar de Atacama as an example. This mapping procedure is proposed as the basis of computationally efficient three-dimensional numerical models, provided that the hydraulic heads of freshwater and mixed waters are corrected based on their density variations to convert them into brine heads. After this correction, the locations of lagoons and wetlands that are characteristic of the marginal zones of the salt flats coincide with the regional minimum water (brine) heads. The different morphologies of the mixing zone resulting from this 3D mapping have been interpreted using a two-dimensional (2D) flow and transport numerical model of an idealized cross-section of the mixing zone. The result of the model shows a slope of the mixing zone that is similar to that obtained by 3D mapping and lower than in previous models. To explain this geometry, the 2D model was used to evaluate the effects of heterogeneity in the mixing zone geometry. The higher the permeability of the upper aquifer is, the lower the slope and the shallower the mixing zone become. This occurs because most of the freshwater lateral recharge flows through the upper aquifer due to its much higher transmissivity, thus reducing the freshwater head. The presence of a few meters of highly permeable materials in the upper part of these hydrogeological systems, such as alluvial fans or karstified evaporites that are frequently associated with the salt flats, is enough to greatly modify the geometry of the saline interface.

Tank 241-AX-104 upper vadose zone cone penetrometer demonstration sampling and analysis plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

FIELD, J.G.

1999-02-02

This sampling and analysis plan (SAP) is the primary document describing field and laboratory activities and requirements for the tank 241-AX-104 upper vadose zone cone penetrometer (CP) demonstration. It is written in accordance with Hanford Tank Initiative Tank 241-AX-104 Upper Vadose Zone Demonstration Data Quality Objective (Banning 1999). This technology demonstration, to be conducted at tank 241-AX-104, is being performed by the Hanford Tanks Initiative (HTI) Project as a part of Tank Waste Remediation System (TWRS) Retrieval Program (EM-30) and the Office of Science and Technology (EM-50) Tanks Focus Area. Sample results obtained as part of this demonstration will providemore » additional information for subsequent revisions to the Retrieval Performance Evaluation (RPE) report (Jacobs 1998). The RPE Report is the result of an evaluation of a single tank farm (AX Tank Farm) used as the basis for demonstrating a methodology for developing the data and analyses necessary to support making tank waste retrieval decisions within the context of tank farm closure requirements. The RPE includes a study of vadose zone contaminant transport mechanisms, including analysis of projected tank leak characteristics, hydrogeologic characteristics of tank farm soils, and the observed distribution of contaminants in the vadose zone in the tank farms. With limited characterization information available, large uncertainties exist as to the nature and extent of contaminants that may exist in the upper vadose zone in the AX Tank Farm. Traditionally, data has been collected from soils in the vadose zone through the installation of boreholes and wells. Soil samples are collected as the bore hole is advanced and samples are screened on site and/or sent to a laboratory for analysis. Some in-situ geophysical methods of contaminant analysis can be used to evaluate radionuclide levels in the soils adjacent to an existing borehole. However, geophysical methods require compensation for well casing interference and soil moisture content and may not be successful in some conditions. In some cases the level of interference must be estimated due to uncertainties regarding the materials used in well construction and soil conditions, Well casing deployment used for many in-situ geophysical methods is relatively expensive and geophysical methods do not generally provide real time values for contaminants. In addition, some of these methods are not practical within the boundaries of the tank farm due to physical constraints, such as underground piping and other hardware. The CP technologies could facilitate future characterization of vadose zone soils by providing vadose zone data in near real-time, reducing the number of soil samples and boreholes required, and reducing characterization costs.« less

Central Projections of Antennal and Labial Palp Sensory Neurons in the Migratory Armyworm Mythimna separata

PubMed Central

Ma, Bai-Wei; Zhao, Xin-Cheng; Berg, Bente G.; Xie, Gui-Ying; Tang, Qing-Bo; Wang, Gui-Rong

2017-01-01

The oriental armyworm, Mythimna separata (Walker), is a polyphagous, migratory pest relying on olfactory cues to find mates, locate nectar, and guide long-distance flight behavior. In the present study, a combination of neuroanatomical techniques were utilized on this species, including backfills, confocal microscopy, and three-dimensional reconstructions, to trace the central projections of sensory neurons from the antenna and the labial pit organ, respectively. As previously shown, the axons of the labial sensory neurons project via the ipsilateral labial nerve and terminate in three main areas of the central nervous system: (1) the labial-palp pit organ glomerulus of each antennal lobe, (2) the gnathal ganglion, and (3) the prothoracic ganglion of the ventral nerve cord. Similarly, the antennal sensory axons project to multiple areas of the central nervous system. The ipsilateral antennal nerve targets mainly the antennal lobe, the antennal mechanosensory and motor center, and the prothoracic and mesothoracic ganglia. Specific staining experiments including dye application to each of the three antennal segments indicate that the antennal lobe receives input from flagellar olfactory neurons exclusively, while the antennal mechanosensory and motor center is innervated by mechanosensory neurons from the whole antenna, comprising the flagellum, pedicle, and scape. The terminals in the mechanosensory and motor center are organized in segregated zones relating to the origin of neurons. The flagellar mechanosensory axons target anterior zones, while the pedicular and scapal axons terminate in posterior zones. In the ventral nerve cord, the processes from the antennal sensory neurons terminate in the motor area of the thoracic ganglia, suggesting a close connection with motor neurons. Taken together, the numerous neuropils innervated by axons both from the antenna and labial palp indicate the multiple roles these sensory organs serve in insect behavior. PMID:29209176

Microbial community of cyanobacteria mats in the intertidal zone of oil-polluted coast of Saudi Arabia.

PubMed

Al-Thukair, A A; Abed, R M M; Mohamed, L

2007-02-01

Cyanobacterial mats are found at various locations along the coast of the Eastern Province of Saudi Arabia. Those mats were affected by severe oil pollution following 1991 oil spill. In this study, samples from Abu Ali Island were collected at three selected sampling sites across the intertidal zone (Lower, Middle, and Upper) in order to understand the effect of extreme environmental conditions of high salinity, temperature and desiccation on distribution of cyanobacteria along the oil polluted intertidal zone. Our investigation of composition of cyanobacteria and diatoms was carried out using light microscopy, and Denaturant Gradient Gel Electrophoresis (DGGE) technique. Light microscopy identification revealed dominant cyanobacteria to be affiliated with genera Phormidium, Microcoleus, and Schizothrix, and to a lesser extent with Oscillatoria, Halothece, and various diatom species. The analysis of DGGE of PCR-amplified 16S rRNA fragments showed that the diversity of cyanobacteria decreases as we proceed from the lower to the upper intertidal zone. Accordingly, the tidal regime, salinity, elevated ambient air temperature, and desiccation periods have a great influence on the distribution of cyanobacterial community in the oil polluted intertidal zone of Abu Ali Island.

Organization of cortical microtubules in graviresponding maize roots

NASA Technical Reports Server (NTRS)

Blancaflor, E. B.; Hasenstein, K. H.

1993-01-01

Immunofluorescence labeling of cortical microtubules (MTs) was used to investigate the relationship between MT arrangement and changes in growth rate of the upper and lower sides of horizontally placed roots of maize (Zea mays L. cv. Merit). Cap cells and cells of the elongation zone of roots grown vertically in light or darkness showed MT arrangements that were transverse (perpendicular) to the growth direction. Microtubules of cells basal to the elongation zone typically showed oblique orientation. Two hours after horizontal reorientation, cap cells of gravicompetent, light-grown and curving roots contained MTs parallel to the gravity vector. The MT arrangement on the upper side of the elongation zone remained transverse but the MTs of the outer four to five layers of cortical cells along the lower side of the elongation zone showed reorientation parallel to the axis of the root. The MTs of the lower epidermis retained their transverse orientation. Dark-grown roots did not curve and did not show reorientation of MTs in cells of the root cap or elongation zone. The data indicate that MT depolymerization and reorientation is correlated with reduction in growth rate, and that MT reorientation is one of the steps of growth control of graviresponding roots.

New U-Pb zircon ages and the duration and division of Devonian time

USGS Publications Warehouse

Tucker, R.D.; Bradley, D.C.; Ver Straeten, C.A.; Harris, A.G.; Ebert, J.R.; McCutcheon, S.R.

1998-01-01

Newly determined U-Pb zircon ages of volcanic ashes closely tied to biostratigraphic zones are used to revise the Devonian time-scale. They are: 1) 417.6 ?? 1.0 Ma for an ash within the conodont zone of Icriodus woschmidti/I. w. hesperius Lochkovian); 2) 408.3 ?? 1.9 Ma for an ash of early Emsian age correlated with the conodont zones of Po. dehiscens--Lower Po. inversus; 3) 391.4 ?? 1.8 Ma for an ash within the Po. c. costatus Zone and probably within the upper half of the zone (Eifelian); and 4) 381.1 ?? 1.3 Ma for an ash within the range of the Frasnian conodont Palmatolepis punctata (Pa. punctata Zone to Upper Pa. hassi Zone). U-Pb zircon ages for two rhyolites bracketing a palyniferous bed of the pusillites-lepidophyta spore zone, are dated at 363.8 ?? 2.2 Ma and 363 ?? 2.2 Ma and 363.4 ?? 1.8 Ma, respectively, suggesting an age of ~363 Ma for a level within the late Famennian Pa. g. expansa Zone. These data, together with other published zircon ages, suggest that the base and top of the Devonian lie close to 418 Ma and 362 Ma, respectively, thus lengthening the period of ~20% over current estimates. We suggest that the duration of the Middle Devonian (Eifelian and Givitian) is rather brief, perhaps no longer than 11.5 Myr (394 Ma-382.5 Ma), and that the Emsian and Famennian are the longest stages in the period with estimated durations of ~15.5 Myr and 14.5 Myr, respectively.

Complementary Therapies for Idiopathic Hirsutism: Topical Licorice as Promising Option

PubMed Central

Faghihi, Gita; Iraji, Fariba; Abtahi-Naeini, Bahareh; Saffar, Bahar; Saffaei, Ali; Pourazizi, Mohsen; Aslani, Abolfazl; Nilforoushzadeh, Mohammad Ali

2015-01-01

Hirsutism is one of the most prevalent health problems in women. The aim of the study was to compare the effect of 755 nm alexandrite hair removal laser with that of alexandrite laser plus topical licorice on the improvement of idiopathic hirsutism. A double-blind, randomized placebo-controlled study was performed on 90 female subjects. The patients were divided into two groups: alexandrite laser plus 15% licorice gel (group A) and placebo (group B). Each subject received one of both products over one side of the face, twice daily for 24 weeks on the hirsute locations. Each group underwent five sessions of alexandrite laser at 6-week intervals. To minimize the effects of confounding variables, the test was performed on two separate zones of patients' skin. The mean ± SD numbers of terminal hairs in group A were 7.05 ± 4.55 for zone 1 and 6.06 ± 3.70 for zone 2. In group B, they were 3.18 ± 1.75 for zone 1 and 2.49 ± 1.63 for zone 2. The difference in the mean number of terminal hairs was statistically significant between the two groups (p < 0.001), and there were no serious adverse reactions. The treatment of idiopathic hirsutism with 755 nm alexandrite laser plus topical licorice is more effective than alexandrite laser only. PMID:26273313

Granite emplacement at the termination of a major Variscan transcurrent shear zone: The late collisional Viseu batholith

NASA Astrophysics Data System (ADS)

Valle Aguado, B.; Azevedo, M. R.; Nolan, J.; Medina, J.; Costa, M. M.; Corfu, F.; Martínez Catalán, J. R.

2017-05-01

A major event of plutonic activity occurred all across the Central Iberian Zone of the Iberian Variscan Belt at the end of Late Paleozoic Variscan collisional tectonism. The present study focuses on the western sector of the Viseu late-post-tectonic batholith (central Portugal), a large composite intrusion comprising three main plutonic units: (a) small bodies of mafic to intermediate composition preferentially concentrated along the northern border, (b) a wide ring of coarse porphyritic biotite monzogranite (Cota-Viseu granite) and (c) a more evolved medium porphyritic, biotite-muscovite monzogranite occupying the central part of the intrusion (Alcafache granite). The compositional zonation pattern of the whole batholith and the complex mixing/mingling relationships between the voluminous Cota-Viseu porphyritic granite and the mafic/intermediate rocks suggest that these melts were withdrawn from a lower crustal source region undergoing partial melting, invasion by mantle-derived mafic magmas, mixing and fractional crystallization. New CA-ID-TIMS U-Pb zircon ages indicate that pluton assembly via multipulse injection of successive magma batches took place between 299.4 ± 0.4 Ma and 296.0 ± 0.6 Ma. A detailed anisotropy of magnetic susceptibility (AMS) survey suggests that pluton emplacement occurred at the extensional termination of a regional-scale, ENE-WSW trending, sinistral D3 shear zone - the Juzbado-Penalva Shear Zone (JPSZ). A dilational opening model involving the development of "en-échelon" tensional gashes at the extensional termination of the fault, followed by progressive opening and widening of north-south trending fractures, provided the space into which the successive magma batches arriving from below were emplaced. Vertical inflation was accommodated by depression of the pluton floor. The proposed model is consistent with the asymmetric wedge-shaped geometry of the intrusion (steep root zone on the northern side, discordant subvertical walls and a shallowing pluton floor towards the south).

The effect of segmented fault zones on earthquake rupture propagation and termination

NASA Astrophysics Data System (ADS)

Huang, Y.

2017-12-01

A fundamental question in earthquake source physics is what can control the nucleation and termination of an earthquake rupture. Besides stress heterogeneities and variations in frictional properties, damaged fault zones (DFZs) that surround major strike-slip faults can contribute significantly to earthquake rupture propagation. Previous earthquake rupture simulations usually characterize DFZs as several-hundred-meter-wide layers with lower seismic velocities than host rocks, and find earthquake ruptures in DFZs can exhibit slip pulses and oscillating rupture speeds that ultimately enhance high-frequency ground motions. However, real DFZs are more complex than the uniform low-velocity structures, and show along-strike variations of damages that may be correlated with historical earthquake ruptures. These segmented structures can either prohibit or assist rupture propagation and significantly affect the final sizes of earthquakes. For example, recent dense array data recorded at the San Jacinto fault zone suggests the existence of three prominent DFZs across the Anza seismic gap and the south section of the Clark branch, while no prominent DFZs were identified near the ends of the Anza seismic gap. To better understand earthquake rupture in segmented fault zones, we will present dynamic rupture simulations that calculate the time-varying rupture process physically by considering the interactions between fault stresses, fault frictional properties, and material heterogeneities. We will show that whether an earthquake rupture can break through the intact rock outside the DFZ depend on the nucleation size of the earthquake and the rupture propagation distance in the DFZ. Moreover, material properties of the DFZ, stress conditions along the fault, and friction properties of the fault also have a critical impact on rupture propagation and termination. We will also present scenarios of San Jacinto earthquake ruptures and show the parameter space that is favorable for rupture propagation through the Anza seismic gap. Our results suggest that a priori knowledge of properties of segmented fault zones is of great importance for predicting sizes of future large earthquakes on major faults.

New Orogenic Model for Taiwan Collision Zone Inferred From Three-dimensional P- and S-wave Velocity Structures and Seismicity

NASA Astrophysics Data System (ADS)

Nagai, S.; Hirata, N.; Sato, H.

2008-12-01

The island of Taiwan is located in the site of ongoing arc-continent collision zone between the Philippine Sea Plate (PSP) and the Eurasian Plate (EUP). Numerous geophysical and geological studies are done in and around Taiwan to develop various models to explain the tectonic processes in the Taiwan region. However, their details have not been known enough, especially under the Central Range. We suggest a new orogenic model for Taiwan orogeny, named 'Upper Crustal Stacking Model', inferred from our tomographic images using three temporary seismic networks with the Central Weather Bureau Seismic Network. These three temporary networks are the aftershock observation after the 1999 Chi-Chi Taiwan earthquake and two dense array observations across central and southern Taiwan, respectively. Tomographic images by the double-difference tomography [Zhang and Thurber, 2003] show a lateral alternate variation of high- and low-velocity, which are well correlated to surface geology and separated by east-dipping boundaries. These images have reliable high-resolution by dense arrays to be able to discuss this alternate variation. We found three high-velocity zones (> 6.0km/s). The westernmost zone corresponds to the subducting EUP. Other two zones are located beneath the Hsuehshan Range and the Eastern Central Range with trends of eastward dipping, respectively. And, we could image low-velocity zone located beneath Backbone Range between the two high-velocity zones clearly. We interpret that these east-dipping high- and low-velocity zones can be divided into two layered blocks and the subducting EUP, each of which consists of a high-velocity body under low-velocity one. Layered blocks can be interpreted as stacked thrust sheets between the subducting EUP and the Northern Luzon Arc, a part of PSP. These thrust sheets are parts of upper- and mid-crust detached from the subducting EUP. The model of continental subduction followed by buoyancy-driven exhumation can explain the existence of stacked thrust sheets. Thus we propose a new orogenic model, as referred to as the 'Upper Crustal Stacking Model'.

The 12 September 1999 Upper East Rift Zone dike intrusion at Kilauea Volcano, Hawaii

USGS Publications Warehouse

Cervelli, Peter; Segall, P.; Amelung, F.; Garbeil, H.; Meertens, C.; Owen, S.; Miklius, Asta; Lisowski, M.

2002-01-01

Deformation associated with an earthquake swarm on 12 September 1999 in the Upper East Rift Zone of Kilauea Volcano was recorded by continuous GPS receivers and by borehole tiltmeters. Analyses of campaign GPS, leveling data, and interferometric synthetic aperture radar (InSAR) data from the ERS-2 satellite also reveal significant deformation from the swarm. We interpret the swarm as resulting from a dike intrusion and model the deformation field using a constant pressure dike source. Nonlinear inversion was used to find the model that best fits the data. The optimal dike is located beneath and slightly to the west of Mauna Ulu, dips steeply toward the south, and strikes nearly east-west. It is approximately 3 by 2 km across and was driven by a pressure of ??? 15 MPa. The total volume of the dike was 3.3 x 106 m3. Tilt data indicate a west to east propagation direction. Lack of premonitory inflation of Kilauea's summit suggests a passive intrusion; that is, the immediate cause of the intrusion was probably tensile failure in the shallow crust of the Upper East Rift Zone brought about by persistent deep rifting and by continued seaward sliding of Kilauea's south flank.

Three-dimensional frictional plastic strain partitioning during oblique rifting

NASA Astrophysics Data System (ADS)

Duclaux, Guillaume; Huismans, Ritske S.; May, Dave

2017-04-01

Throughout the Wilson cycle the obliquity between lithospheric plate motion direction and nascent or existing plate boundaries prompts the development of intricate three-dimensional tectonic systems. Where oblique divergence dominates, as in the vast majority of continental rift and incipient oceanic domains, deformation is typically transtensional and large stretching in the brittle upper crust is primarily achieved by the accumulation of displacement on fault networks of various complexity. In continental rift depressions such faults are initially distributed over tens to hundreds of kilometer-wide regions, which can ultimately stretch and evolve into passive margins. Here, we use high-resolution 3D thermo-mechanical finite element models to investigate the relative timing and distribution of localised frictional plastic deformation in the upper crust during oblique rift development in a simplified layered lithosphere. We vary the orientation of a wide oblique heterogeneous weak zone (representing a pre-existing geologic feature like a past orogenic domain), and test the sensitivity of the shear zones orientation to a range of noise distribution. These models allow us to assess the importance of material heterogeneities for controlling the spatio-temporal shear zones distribution in the upper crust during oblique rifting, and to discuss the underlying controls governing oblique continental breakup.

Mantle Upwellings Below the Ibero-Maghrebian Region with a Common Deep Source from P Travel-time Tomography

NASA Astrophysics Data System (ADS)

Civiero, C.; Custodio, S.; Silveira, G. M.; Rawlinson, N.; Arroucau, P.

2017-12-01

The processes responsible for the geodynamical evolution of the Ibero-Maghrebian domain are still enigmatic. Several geophysical studies have improved our understanding of the region, but no single model has been accepted yet. This study takes advantage of the dense station networks deployed from France in the north to Canary Islands and Morocco in the south to provide a new high-resolution P-wave velocity model of the structure of the upper-mantle and top of the lower mantle. These images show subvertical small-scale upwellings below Atlas Range, Canary Islands and Central Iberia that seem to cross the transition zone. The results, together with geochemical evidence and a comparison with previous global tomographic models, reveal the ponding or flow of deep-plume material beneath the transition zone, which seems to feed upper-mantle "secondary" pulses. In the upper mantle the plumes, in conjunction with the subduction-related upwellings, allow the hot mantle to rise in the surrounding zones. During its rising, the mantle interacts with horizontal SW slab-driven flow which skirts the Alboran slab and connects with the mantle upwelling below Massif Central through the Valencia Trough rift.

Life on the boundary: Environmental factors as drivers of habitat distribution in the littoral zone

NASA Astrophysics Data System (ADS)

Cefalì, Maria Elena; Cebrian, Emma; Chappuis, Eglantine; Pinedo, Susana; Terradas, Marc; Mariani, Simone; Ballesteros, Enric

2016-04-01

The boundary between land and sea, i.e. the littoral zone, is home to a large number of habitats whose distribution is primarily driven by the distance to the sea level but also by other environmental factors such as littoral's geomorphological features, wave exposure, water temperature or orientation. Here we explore the relative importance of those major environmental factors that drive the presence of littoral rocky habitats along 1100 Km of Catalonia's shoreline (Spain, NW Mediterranean) by using Geographic Information Systems and Generalized Linear Models. The distribution of mediolittoral and upper infralittoral habitats responded to different environmental factors. Mediolittoral habitats showed regional differences drawn by sea-water temperature and substrate type. Wave exposure (hydrodynamism), slope and geological features were only relevant to those mediolittoral habitats with specific environmental needs. We did not find any regional pattern of distribution in upper infralittoral habitats, and selected factors only played a moderate role in habitat distribution at the local scale. This study shows for the first time that environmental factors determining habitat distribution differ within the mediolittoral and the upper infralittoral zones and provides the basis for further development of models oriented at predicting the distribution of littoral marine habitats.

The Role of Neurotrophins in Neurotransmitter Release

PubMed Central

Tyler, William J.; Perrett, Stephen P.; Pozzo-Miller, Lucas D.

2009-01-01

The neurotrophins (NTs) have recently been shown to elicit pronounced effects on quantal neurotransmitter release at both central and peripheral nervous system synapses. Due to their activity-dependent release, as well as the subcellular localization of both protein and receptor, NTs are ideally suited to modify the strength of neuronal connections by “fine-tuning” synaptic activity through direct actions at presynaptic terminals. Here, using BDNF as a prototypical example, the authors provide an update of recent evidence demonstrating that NTs enhance quantal neurotransmitter release at synapses through presynaptic mechanisms. The authors further propose that a potential target for NT actions at presynaptic terminals is the mechanism by which terminals retrieve synaptic vesicles after exocytosis. Depending on the temporal demands placed on synapses during high-frequency synaptic transmission, synapses may use two alternative modes of synaptic vesicle retrieval, the conventional slow endosomal recycling or a faster rapid retrieval at the active zone, referred to as “kiss-and-run.” By modulating Ca2+ microdomains associated with voltage-gated Ca2+ channels at active zones, NTs may elicit a switch from the slow to the fast mode of endocytosis of vesicles at presynaptic terminals during high-frequency synaptic transmission, allowing more reliable information transfer and neuronal signaling in the central nervous system. PMID:12467374

The role of neurotrophins in neurotransmitter release.

PubMed

Tyler, William J; Perrett, Stephen P; Pozzo-Miller, Lucas D

2002-12-01

The neurotrophins (NTs) have recently been shown to elicit pronounced effects on quantal neurotransmitter release at both central and peripheral nervous system synapses. Due to their activity-dependent release, as well as the subcellular localization of both protein and receptor, NTs are ideally suited to modify the strength of neuronal connections by "fine-tuning" synaptic activity through direct actions at presynaptic terminals. Here, using BDNF as a prototypical example, the authors provide an update of recent evidence demonstrating that NTs enhance quantal neurotransmitter release at synapses through presynaptic mechanisms. The authors further propose that a potential target for NT actions at presynaptic terminals is the mechanism by which terminals retrieve synaptic vesicles after exocytosis. Depending on the temporal demands placed on synapses during high-frequency synaptic transmission, synapses may use two alternative modes of synaptic vesicle retrieval, the conventional slow endosomal recycling or a faster rapid retrieval at the active zone, referred to as "kiss-and-run." By modulating Ca2+ microdomains associated with voltage-gated Ca2+ channels at active zones, NTs may elicit a switch from the slow to the fast mode of endocytosis of vesicles at presynaptic terminals during high-frequency synaptic transmission, allowing more reliable information transfer and neuronal signaling in the central nervous system.

Stratification of Seismic Anisotropy Beneath Hudson Bay

NASA Astrophysics Data System (ADS)

Darbyshire, F. A.; Eaton, D. W.; Bastow, I. D.

2012-12-01

The Hudson Bay region has a complex tectonic history spanning ~4 Ga of Earth's evolution. During the ~1.8 Ga Trans-Hudson orogeny, the Archean Superior and Western Churchill cratons collided following the subduction of a Pacific-scale ocean. It is thought that a significant amount of juvenile material is preserved in the Trans-Hudson Orogen, in part due to the complex double-indentor geometry of the Superior-Churchill collision. In the region of interest, the orogen lies beneath a large but shallow Paleozoic intra-cratonic basin. Studies of the crust and upper mantle beneath this region have been enabled through the HuBLE (Hudson Bay Lithospheric Experiment) project, through the deployment of broadband seismographs around the Bay and across the islands to the north. A surface-wave tomography study has taken advantage of the data coverage, providing new information on phase velocity heterogeneity and anisotropy for wave periods of 25-200 seconds (equivalent to depths from the lower crust to ~300 km). On a large scale, our results show that the entire region is underlain by a seismically fast lithospheric lid corresponding to the continental keel. The lithospheric thickness ranges from ~180km in the northeast, beneath a zone of Paleozoic rifting, to ~280km beneath central Hudson Bay. Within the lithosphere, seismic velocities vary laterally, including high-velocity material wrapping around the Bay in the uppermost mantle. In the mid-lithosphere, two high-velocity cores are imaged, with a zone of lower velocity between them beneath the Bay. We interpret these high-velocity structures to represent the strongest central cores of the Superior and Churchill cratons, with more-juvenile material preserved between them. The near-vertical geometry of the lower-velocity zone suggests that it is only the effects of terminal collision of the cratonic cores, rather than any preceding subduction, that is preserved today. The lowermost lithosphere has a more uniform velocity, and may represent a pervasive zone of metasomatism or underplating. Anisotropy patterns across the region also vary with depth, suggesting ~3 layers of stratification of lithospheric fabric. At the shallowest depths, anisotropic fast directions wrap around the Bay in a similar fashion to the patterns of isotropic wavespeed. The upper lithospheric mantle below is characterized by relatively weak and incoherent anisotropy; however the mid-to-lower lithosphere shows stronger anisotropy, with a pattern of fast directions broadly consistent with the tectonics of the Superior-Churchill collision as inferred from potential-field data. This may suggest some degree of coherency of deformation between the crust, uppermost mantle and lower lithosphere. These models of seismic wavespeed variation beneath the Hudson Bay region reveal the preservation of a major collision zone during the assembly of the Laurentian continental mass, and also suggest that the Archean cratons can be subdivided into different lithospheric domains that reflect their tectonic history but do not necessarily correspond to surface geological boundaries.

33 CFR 165.1706 - Gastineau Channel, Juneau, Alaska-Safety Zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... at 58°17′41″ N, 134°24′22″ W used to conduct fireworks displays. (b) Effective date. The safety zone becomes effective on July 3 each year at 10 p.m. ADT. It terminates at the conclusion of the fireworks... Port. If the fireworks display is postponed because of inclement weather, the date and duration of the...

Studying Upper-Limb Amputee Prosthesis Use to Inform Device Design

DTIC Science & Technology

2016-10-01

study of the resulting videos led to a new prosthetics-use taxonomy that is generalizable to various levels of amputation and terminal devices. The...taxonomy was applied to classification of the recorded videos via custom tagging software with midi controller interface. The software creates...a motion capture studio and video cameras to record accurate and detailed upper body motion during a series of standardized tasks. These tasks are

Coseismic rupturing stopped by Aso volcano during the 2016 Mw 7.1 Kumamoto earthquake, Japan.

PubMed

Lin, A; Satsukawa, T; Wang, M; Mohammadi Asl, Z; Fueta, R; Nakajima, F

2016-11-18

Field investigations and seismic data show that the 16 April 2016 moment magnitude (M w ) 7.1 Kumamoto earthquake produced a ~40-kilometer-long surface rupture zone along the northeast-southwest-striking Hinagu-Futagawa strike-slip fault zone and newly identified faults on the western side of Aso caldera, Kyushu Island, Japan. The coseismic surface ruptures cut Aso caldera, including two volcanic cones inside it, but terminate therein. The data show that northeastward propagation of coseismic rupturing terminated in Aso caldera because of the presence of magma beneath the Aso volcanic cluster. The seismogenic faults of the 2016 Kumamoto earthquake may require reassessment of the volcanic hazard in the vicinity of Aso volcano. Copyright © 2016, American Association for the Advancement of Science.

Regional tectonic framework of the Pranhita Godavari basin, India

NASA Astrophysics Data System (ADS)

Biswas, S. K.

2003-03-01

The Pranhita-Godavari Gondwana rift (PGR) has a co-genetic relationship with Permo-Triassic reactivation of the Narmada-Son Geofracture (NSG). The Satpura Gondwana basin represents the terminal depocentre against the NSG, which restricted the northwestward propagation of the PGR. The NE-SW tensional stress responsible for the NW-SE trending PGR could not propagate beyond the ramp formed by uplift along the NSG and transformed kinetically into an ENE directed horizontal shear along the NSG, inducing large scale strike-slip movements. The latter dynamics were responsible for ENE extension of the Satpura rift as a pull-apart basin. The PGR extends up to the present east coast of India, where it is apparently terminated by the NE-SW trending Bapatla ridge along the Eastern Ghat Rift (EGR). The subsurface data, however, shows that the PGR extends across the Bapatla ridge and continues beneath the Cretaceous-Tertiary sediments of the Krishna-Godavari basin (KG) in the EGR. Thus, the Permo-Triassic PGR appears to have continued in the Indo-Antarctic plate before the Cretaceous break up. The EGR, during break up of the continents, cuts across the PGR and the KG basin was superimposed on it. The PGR site is located on a paleo-suture between the Dharwar and Bastar proto-cratons. The master faults developed bordering the rift, and the intra-rift higher order faults followed the pre-existing fabric. The transverse transfer zones manifested as basement ridges, divide the rift into segments of tectono-sedimentary domains. The major domains are the Chintalapudi, Godavari, and Chandrapur sub-basins, each of which subsided differentially. The central Godavari sub-basin subsided most and shows maximum structural complexity and sediment accommodation. The rifting started with initial half-graben faulting along the northeastern master fault and expanded by successive half graben faulting. This gave rise to intra-basinal horsts and grabens, which exercised control on the syn-rift sedimentation. The southeastern boundary fault developed as a strike-slip fault in response to plate rotation and the rift expansion was constrained by it.The basin fill sediments were deposited during two rifting events—Early Permian to (?) Early Jurassic Lower Gondwana rifting, and Early Cretaceous Upper Gondwana rifting. The Lower Gondwana sedimentation started with a pre-rift crustal sagging over the rift site and was filled by glaciogenic Talchir sediments. This was followed by syn-rift-fluvial sedimentation in repeating cycles during the early to late rift stages. Early Cretaceous Chikiala and Gangapur sediments were deposited during the Upper Gondwana rifting. The fluvial cycles were tectonically controlled during each rift stage. The absence of igneous intrusions indicates that the PGR is a passive rift in contrast to the rifts developed in the NSG zone.

Preliminary palynological zonation of the Chinle formation, southwestern U.S.A., and its correlation to the Newark supergroup (eastern U.S.A.)

USGS Publications Warehouse

Litwin, R.J.; Traverse, A.; Ash, S.R.

1991-01-01

Three informal palynological assemblage zones can be distinguished in samples from Chinle Formation outcrops in Utah, Arizona and New Mexico. The oldest zone (zone I) is in the Temple Mountain Member in southeastern Utah; the middle zone (zone II) is in the Shinarump, Moss Back, Monitor Butte and (lower part of the) Petrified Forest Members (Utah, Arizona and New Mexico); the youngest zone (zone III) is in the upper Petrified Forest Member and silstone member in Arizona and Utah and the silstone member in northcentral New Mexico. Present palynological evidence suggests that Chinle deposition on the Colorado Plateau began locally in late Carnian time and continued at least into the early part of Norian time of the Late Triassic period. Because the upper boundary of the Chinle Formation is an unconformity and the overlying formations are palynologically barren, the length of time represented by this stratigraphic hiatus is not known with certainty. Current palynological evidence suggests, however, that the unconformity at the top of the Chinle cannot be older than early Norian nor younger than Hettangian. Zones I, II and III can now be recognized in the palynomorph assemblage sequences from the Eastern Mesozoic basins, which modifies earlier palynological zonations for the lower portions of the Newark Supergroup. This is based on our identification of palynomorphs not previously known from portions of the Newark Supergroup and the discovery that specific biomarker taxa combinations are the same for both the western and eastern palynomorph sequences. At present palynomorph assemblages from the Chinle Formation and Newark Supergroup compare more closely for zones II and III than they do for zone I, but research is still in progress. ?? 1991.

Hydrogeologic evaluation of the Upper Floridan aquifer in the southwestern Albany area, Georgia

USGS Publications Warehouse

Warner, Debbie

1997-01-01

A cooperative study by the Albany Water, Gas, and Light Commission and the U.S. Geological Survey was conducted to evaluate the hydrogeology of the Upper Floridan aquifer in an area southwest of Albany and west of the Flint River in Dougherty County, Ga. The study area lies in the Dougherty Plain district of the Coastal Plain physiographic province. In this area, the Upper Floridan aquifer is comprised of the upper Eocene Ocala Limestone, confined below by the middle Eocene Lisbon Formation, and semiconfined above by the undifferentiated Quaternary overburden. The overburden ranges in thickness from about 30 to 50 feet and consists of fine to coarse quartz sand, clayey sand, sandy clay, and clay. The Upper Floridan aquifer has been subdivided into an upper water-bearing zone and a lower water-bearing zone based on differences in lithology and yield. In the study area, the upper water-bearing zone generally consists of dense, highly weathered limestone of low permeability and ranges in thickness from 40 to 80 feet. The lower water-bearing zone consists of hard, slightly weathered limestone that exhibits a high degree of secondary permeability that has developed along fractures and joints, and ranges in thickness from about 60 to 80 feet. Borehole geophysical logs and borehole video surveys indicate two areas of high permeability in the lower water-bearing zone-one near the top and one near the base of the zone. A wellfield consisting of one production well and five observation-well clusters (one deep, intermediate, and shallow well in each cluster) was constructed for this study. Spinner flowmeter tests were conducted in the production well between the depths of 110 and 140 feet below land surface to determine the relative percentages of water contributed by selected vertical intervals of the lower water-bearing zone. Pumping rates during these tests were 1,080, 2,200, and 3,400 gallons per minute. The results of these pumping tests show that the interval between 118 and 124 feet below land surface contributes a significant percentage of the total yield to the well. An aquifer test was conducted by pumping the production well at a constant rate of 3,300 gallons per minute for about 49 hours. Time-dependent water-level data were collected throughout the pumping and recovery phases of the test in the pumped well and the observation wells. The maximum measured drawdown in the observation wells was about 2.6 ft. At about 0.5 mile from the pumped well, there was little measurable effect from pumping. Water levels increased during the test in wells located within about 3.75 miles of the Flint River (about 0.5 miles east of the pumping well). This water-level increase correlated with a 3.5-feet increase in the stage of the Flint River. The hydraulic characteristics of the Upper Floridan aquifer were evaluated using the Hantush-Jacob curve-matching and Jacob straight-line methods. Using the Hantush-Jacob method, values for transmissivity ranged from about 120,000 to 506,000 feet squared per day; values for storage coefficient ranged from 1.4 x 10-4 to 6.3 x 10-4; and values for vertical hydraulic conductivity of the overlying sediments ranged from 4.9 to 6.8 feet per day. Geometric averages for these values of transmissivity, storage coefficient, and vertical hydraulic conductivity were calculated to be 248,000 feet squared per day, 2.7 x 10-4, and 5.5 feet per day, respectively. If a dual porosity aquifer model (fracture flow plus matrix flow) is assumed instead of leakage, and the Jacob straight-line method is used with late time-drawdown data, the calculated transmissivity of the fractures ranged from about 233,000 to 466,000 feet squared per day; and storage coefficient of the fractures plus the matrix ranged from 5.1 x 10-4 to 2.9 x 10-2.

Soil water dynamics during precipitation in genetic horizons of Retisol

NASA Astrophysics Data System (ADS)

Zaleski, Tomasz; Klimek, Mariusz; Kajdas, Bartłomiej

2017-04-01

Retisols derived from silty deposits dominate in the soil cover of the Carpathian Foothills. The hydrophysical properties of these are determined by the grain-size distribution of the parent material and the soil's "primary" properties shaped in the deposition process. The other contributing factors are the soil-forming processes, such as lessivage (leaching of clay particles), and the morphogenetic processes that presently shape the relief. These factors are responsible for the "secondary" differentiation of hydrophysical properties across the soil profile. Both the primary and secondary hydrophysical properties of soils (the rates of water retention, filtration and infiltration, and the moisture distribution over the soil profile) determine their ability to take in rainfall, the amount of rainwater taken in, and the ways of its redistribution. The aims of the study, carried out during 2015, were to investigate the dynamics of soil moisture in genetic horizons of Retisol derived from silty deposits and to recognize how fast and how deep water from precipitation gets into soil horizons. Data of soil moisture were measured using 5TM moisture and temperature sensor and collected by logger Em50 (Decagon Devices USA). Data were captured every 10 minutes from 6 sensors at depths: - 10 cm, 20 cm, 40 cm, 60 cm and 80 cm. Precipitation data come from meteorological station situated 50 m away from the soil profile. Two zones differing in the type of water regime were distinguished in Retisol: an upper zone comprising humic and eluvial horizons, and a lower zone consisting of illuvial and parent material horizons. The upper zone shows smaller retention of water available for plants, and relatively wide fluctuations in moisture content, compared to the lower zone. The lower zone has stable moisture content during the vegetation season, with values around the water field capacity. Large changes in soil moisture were observed while rainfall. These changes depend on the volume of the precipitation and soil moisture before the precipitation. The following changes of moisture in the soil profile during precipitation were distinguished: if soil moisture in upper zone horizons oscillates around field capacity (higher than 0.30 m3ṡm-3) there is an evident increase in soil moisture also in the lower zone horizons. If soil moisture in the upper zone horizons is much lower than the field capacity (less than 0.20 m3ṡm-3), the soil moisture in the lower zone has very little fluctuations. The range of wetting front in the soil profile depends on the volume of the precipitation and soil moisture. The heavier precipitation, the wetting front in soil profile reaches deeper horizons. The wetter the soil is, the faster soil moisture in the deeper genetic horizons increase. This Research was financed by the Ministry of Science and Higher Education of the Republic of Poland, DS No. 3138/KGiOG/2016.

Spatio-temporal variation in distribution of aquatic species and their habitats in a reservoir transition zone

Treesearch

Andy Dolloff; Craig Roghair; Colin Krause; John Moran; Allison Cochran; Mel Warren; Susan Adams; Wendell Haag

2016-01-01

Dams convert riverine habitat to a series of reaches or zones where differences in flow, habitat, and biota, both downstream and in reservoirs, are obvious and well described. At the upstream extent of a reservoir, however, is a transitional reach or zone that contains characteristics of riverine habitat both in the upper reservoir and in tributaries connected to the...

Foraminiferal and radiolarian biostratigraphy of the youngest (Late Albian through Late Cenomanian) sediments of the Tatra massif, Central Western Carpathians

NASA Astrophysics Data System (ADS)

Bąk, Krzysztof; Bąk, Marta

2013-06-01

Bąk, K. and Bąk M. 2013. Foraminiferal and radiolarian biostratigraphy of the youngest (Late Albian through Late Cenomanian) sediments of the Tatra massif, Central Western Carpathians. Acta Geologica Polonica, 63 (2), 223-237. Warszawa. The foraminiferal and radiolarian biostratigraphy of selected sections of the Zabijak Formation, the youngest sediments of the Tatra massif (Central Western Carpathians), have been studied. Benthic foraminifers, mainly agglutinated species, occur abundantly and continuously throughout the studied succession, while planktic foraminifers are generally sparse. Five planktic and two benthic foraminiferal zones have been recognized. The marly part of the Zabijak Formation comprises the Pseudothalmanninella ticinensis (Upper Albian) through the Rotalipora cushmani (Upper Cenomanian) planktic foraminiferal zones, and the Haplophragmoides nonioninoides and Bulbobaculites problematicus benthic foraminiferal zones. The radiolarians were recognized exclusively in the Lower Cenomanian part of the formation.

Stratification of welding fumes and grinding particles in a large factory hall equipped with displacement ventilation.

PubMed

Niemelä, R; Koskela, H; Engström, K

2001-08-01

The purpose of the study was to investigate the performance of displacement ventilation in a large factory hall where large components of stainless steel for paper, pulp and chemical industries were manufactured. The performance of displacement ventilation was evaluated in terms of concentration distributions of welding fumes and grinding particles, flow field of the supply air and temperature distributions. Large differences in vertical stratification patterns between hexavalent chromium (Cr(VI)) and other particulate contaminants were observed. The concentration of Cr(VI) was notably lower in the zone of occupancy than in the upper part of the factory hall, whereas the concentrations of total airborne particles and trivalent chromium (Cr(III)) were higher in the occupied zone than in the upper zone. The stratification of Cr(VI) had the same tendency as the air temperature stratification caused by the displacement flow field.

Hydrogeologic framework and geologic structure of the Floridan aquifer system and intermediate confining unit in the Lake Okeechobee area, Florida

USGS Publications Warehouse

Reese, Ronald S.

2014-01-01

The successful implementation of aquifer storage and recovery (ASR) as a water-management tool requires detailed information on the hydrologic and hydraulic properties of the potential water storage zones. This report presents stratigraphic and hydrogeologic sections of the upper part of the Floridan aquifer system and the overlying confining unit or aquifer system in the Lake Okeechobee area, and contour maps of the upper contacts of the Ocala Limestone and the Arcadia Formation, which are represented in the sections. The sections and maps illustrate hydrogeologic factors such as confinement of potential storage zones, the distribution of permeability within the zones, and geologic features that may control the efficiency of injection, storage, and recovery of water, and thus may influence decisions on ASR activities in areas of interest to the Comprehensive Everglades Restoration Plan.

Rapid change of chromomeric and pairing patterns of polytene chromosome tips in D. melanogaster: migration of polytene-nonpolytene transition zone?

PubMed

Roberts, P A

1979-07-01

The high variability of chromomeric patterns in near-terminal regions of polytene chromosome arms has been explored in a number of races, strains and hybrids of Drosophila melanogaster. Traditional explanations for tip differences between strains (differential compaction of chromatin, somatic or germinal deletion) are examined and, in the light of the reported observations, rejected. The range of polytene tip variability and rates of change in wild races are greater than has been supposed: strains formerly considered to be terminally deleted appear to gain terminal bands; others, formerly considered normal, appear to have lost them. Strains with high cell-to-cell tip variability are also described. Cell-to-cell variations, as well as much of the observed rapid changes in tip appearance, are probably due to heritable differences in the location of an abrupt transition zone between polytene and nonpolytene chromatin. A quantitative relationship between the amount of certain subterminal bands present and the frequency of tip association of nonhomologous chromosomes is shown and its possible significance for chromosome is shown and its possible for chromosome pairing discussed.

Results of coalbed-methane drilling, Meadowfill Landfill, Harrison County, West Virginia: Chapter G.4 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Ruppert, Leslie F.; Trippi, Michael H.; Fedorko, Nick; Grady, William C.; Eble, Cortland F.; Schuller, William A.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

Methane contents of desorbed gas from coal samples in the Meadowfill Landfill study area ranged from 14.87 to 98.73 percent (corrected for air contamination) for the Harlem coal bed and Clarion coal zone, respectively. Proportions of methane to the sum of the higher molecular weight hydrocarbons ranged from about 40 to 340 as the desorbed gas contained only a small percentage of higher weight hydrocarbons. Coalbed methane from the Upper Kittanning upper split and the Upper Kittanning coal beds is thermogenic in origin with isotopic composition of carbon (carbon 13, 13C) in methane (expressed as δ13C in units of parts per thousand (per mil) relative to the Vienna Peedee belemnite (VPDB) standard) ranging from -46.6 to -48.7 per mil. Coalbed methane from the Brush Creek and Upper Freeport coal beds and the Clarion coal zone contains some biogenic methane with δ13C values ranging from -51.05 to -51.56 per mil.

Provenance of Mesozoic clastic rocks within the Bangong-Nujiang suture zone, central Tibet: Implications for the age of the initial Lhasa-Qiangtang collision

NASA Astrophysics Data System (ADS)

Li, Shun; Guilmette, Carl; Ding, Lin; Xu, Qiang; Fu, Jia-Jun; Yue, Ya-Hui

2017-10-01

The Bangong-Nujiang suture zone, separating the Lhasa and Qiangtang blocks of the Tibetan Plateau, is marked by remnants of the Bangong-Nujiang oceanic basin. In the Gaize area of central Tibet, Mesozoic sedimentary strata recording the evolution of the basin and subsequent collision between these two blocks include the Upper Triassic-Lower Jurassic turbidites of the Mugagangri Group, the Upper Jurassic-Lower Cretaceous sandstone-dominated Wuga and Shamuluo formations, and the Upper Cretaceous molasse deposits of the Jingzhushan Formation. The Shamuluo and Jingzhushan formations rest unconformably on the underlying Mugagangri Group and Wuga Formation, respectively. In this contribution, we analyze petrographic components of sandstones and U-Pb-Hf isotopic compositions of detrital zircons from the Wuga and Jingzhushan formations for the first time. Based on the youngest detrital zircon ages, the maximum depositional ages of the Wuga and Jingzhushan formations are suggested to be ∼147-150 Ma and ∼79-91 Ma, respectively. Petrographic and isotopic results indicate that sediments in the Wuga Formation were mainly sourced from the accretionary complex (preserved as the Mugagangri Group) in the north, while sediments in the Jingzhushan Formation have mixed sources from the Lhasa block, the Qiangtang block and the intervening suture zone. Provenance analysis, together with regional data, suggests that the Upper Jurassic-Lower Cretaceous Wuga and Shamuluo formations were deposited in a peripheral foreland basin and a residual-sea basin, respectively, in response to the Lhasa-Qiangtang collision, whereas the Upper Cretaceous Jingzhushan Formation reflects continental molasse deposition during the post-collisional stage. The development of the peripheral foreland basin evidenced by deposition of the Wuga Formation reveals that the age of the initial Lhasa-Qiangtang collision might be the latest Jurassic (∼150 Ma).

Periorbital and Intraorbital Studies of the Terminal Branches of the Ophthalmic Artery for Periorbital and Glabellar Filler Placements.

PubMed

Tansatit, Tanvaa; Apinuntrum, Prawit; Phetudom, Thavorn

2017-06-01

Filler injections for sunken upper eyelid correction and glabellar augmentation at the orbitoglabellar region need to be performed correctly. Precise knowledge of the emerging sites of all terminal branches of the ophthalmic artery is essential for these procedures to be conducted safely. The terminal branches of the ophthalmic artery were studied in both periorbital and intraorbital dissections. The aim of this study was to verify the critical positions of the emerging sites at the orbital septum that may act as potential retrograde channels for filler emboli. In the 40 eyes examined, the branches of the ophthalmic artery were found to emerge from four different sites. Two substantial emerging sites were situated on both sides of the trochlea of the superior oblique muscle. These sites were located at the superior part of the medial orbital rim (SMOR) and are alternatively named as the epitrochlear and the subtrochlear emerging sites. The other two sites can be regarded as accessory emerging sites due to the comparably smaller artery. Dissection of the intraorbital region revealed small periosteal branches of the infraorbital artery which coursed anteriorly on the orbital floor to form anastomoses with the lacrimal artery. In other areas of the orbital floor, no branches extended from the infraorbital artery. In front of the lacrimal gland, very minute branches descended and coursed along both margins of the superior tarsus but did not course outside the lateral orbital rim. A danger zone was located at the SMOR, where the ophthalmic branches emerge to form anastomotic channels. Compression at the trochlea guarantees safe injection of filler, reducing the risk of complication. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Causes of complexity in a fallout dominated plinian eruption sequence: 312 ka Fasnia Member, Diego Hernández Formation, Tenerife, Spain

NASA Astrophysics Data System (ADS)

Edgar, C. J.; Cas, R. A. F.; Olin, P. H.; Wolff, J. A.; Martí, J.; Simmons, J. M.

2017-10-01

The 312 ka Fasnia eruption from the Las Cañadas Caldera on Tenerife, Canary Islands, Spain, produced a complex sequence of twenty-two intercalated units, including 7 pumice fall, 7 ignimbrite and 8 ash surge and fall deposits that define two distinct eruption sequences (Lower and Upper Fasnia sequences). The fallout units themselves are internally complex, reflecting waxing and waning of the eruption column, while many of the ignimbrites reflect multiple intra-plinian partial column collapse events associated with the injection of lithic clasts into the eruption column. The Lower and Upper Fasnia eruption phases were each terminated by caldera collapse and complete column collapse events. Probable blockage of the conduit and vent system during Lower Fasnia caldera collapse event briefly terminated the eruption, resulting in a short-lived period of erosion and sedimentation prior to the onset of the Upper Fasnia phase. The transition to the Upper Fasnia eruption phase coincided with the eruption of more geochemically homogeneous pyroclasts. In total, 62 km3 of tephra were erupted, including 49 km3 of juvenile clasts and > 12 km3 of lithic clasts. The DRE volume of magma erupted was 13 km3 (Lower Fasnia > 5 km3, Upper Fasnia > 8 km3), two thirds of which ( 9-10 km3) was deposited purely by fallout. The Fasnia Member is one of the most complex plinian sequences known.

Variations in Soil Properties and Herbicide Sorption Coefficients with Depth in Relation to PRZM (Pesticide Root Zone Model) Calculations

USDA-ARS?s Scientific Manuscript database

There are few experimental data available on how herbicide sorption coefficients change across small increments within soil profiles. Soil profiles were obtained from three landform elements (eroded upper slope, deposition zone, and eroded waterway) in a strongly eroded agricultural field and segmen...

76 FR 33639 - Safety Zone; New York Water Taxi 10th Anniversary Fireworks

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-09

...-AA00 Safety Zone; New York Water Taxi 10th Anniversary Fireworks, Upper New York Bay, Red Hook, NY... New York Water Taxi. The fireworks will commence at 9 p.m. on June 21, 2011 and will last... CFR Part 165 Harbors, Marine safety, Navigation (water), Reporting and recordkeeping requirements...

A review of the regional geophysics of the Arizona Transition Zone

NASA Technical Reports Server (NTRS)

Hendricks, J. D.; Plescia, J. B.

1991-01-01

A review of existing geophysical information and new data presented in this special section indicate that major changes in crustal properties between the Basin and Range and Colorado Plateau occur in, or directly adjacent to, the region defined as the Arizona Transition Zone. Although this region was designated on a physiographic basis, studies indicate that it is also the geophysical transition between adjoining provinces. The Transition Zone displays anomalous crustal and upper mantle seismic properties, shallow Curie isotherms, high heat flow, and steep down-to-the-plateau Bouguer gravity gradients. Seismic and gravity studies suggest that the change in crustal thickness, from thin crust in the Basin and Range to thick crust in the Colorado Plateau, may occur as a series of steps rather than a planar surface. Anomalous P wave velocities, high heat flow, shallow Curie isotherms, and results of gravity modeling suggest that the upper mantle is heterogeneous in this region. A relatively shallow asthenosphere beneath the Basin and Range and Transition Zone contrasted with a thick lithosphere beneath the Colorado Plateau would be one explanation that would satisfy these geophysical observations.

Collagen Fiber Orientation and Dispersion in the Upper Cervix of Non-Pregnant and Pregnant Women

PubMed Central

Myers, Kristin M.; Vink, Joy Y.; Wapner, Ronald J.; Hendon, Christine P.

2016-01-01

The structural integrity of the cervix in pregnancy is necessary for carrying a pregnancy until term, and the organization of human cervical tissue collagen likely plays an important role in the tissue’s structural function. Collagen fibers in the cervical extracellular matrix exhibit preferential directionality, and this collagen network ultrastructure is hypothesized to reorient and remodel during cervical softening and dilation at time of parturition. Within the cervix, the upper half is substantially loaded during pregnancy and is where the premature funneling starts to happen. To characterize the cervical collagen ultrastructure for the upper half of the human cervix, we imaged whole axial tissue slices from non-pregnant and pregnant women undergoing hysterectomy or cesarean hysterectomy respectively using optical coherence tomography (OCT) and implemented a pixel-wise fiber orientation tracking method to measure the distribution of fiber orientation. The collagen fiber orientation maps show that there are two radial zones and the preferential fiber direction is circumferential in a dominant outer radial zone. The OCT data also reveal that there are two anatomic regions with distinct fiber orientation and dispersion properties. These regions are labeled: Region 1—the posterior and anterior quadrants in the outer radial zone and Region 2—the left and right quadrants in the outer radial zone and all quadrants in the inner radial zone. When comparing samples from nulliparous vs multiparous women, no differences in these fiber properties were noted. Pregnant tissue samples exhibit an overall higher fiber dispersion and more heterogeneous fiber properties within the sample than non-pregnant tissue. Collectively, these OCT data suggest that collagen fiber dispersion and directionality may play a role in cervical remodeling during pregnancy, where distinct remodeling properties exist according to anatomical quadrant. PMID:27898677

Three-dimensional lithospheric electrical structure of Southern Granulite Terrain, India and its tectonic implications

NASA Astrophysics Data System (ADS)

Patro, Prasanta K.; Sarma, S. V. S.; Naganjaneyulu, K.

2014-01-01

crustal as well as the upper mantle lithospheric electrical structure of the Southern Granulite Terrain (SGT) is evaluated, using the magnetotelluric (MT) data from two parallel traverses: one is an 500 km long N-S trending traverse across SGT and another a 200 km long traverse. Data space Occam 3-D inversion was used to invert the MT data. The electrical characterization of lithospheric structure in SGT shows basically a highly resistive (several thousands of Ohm meters) upper crustal layer overlying a moderately resistive (a few hundred Ohm meters) lower crustal layer which in turn is underlain by the upper mantle lithosphere whose resistivity shows significant changes along the traverse. The highly resistive upper crustal layer is interspersed with four major conductive features with three of them cutting across the crustal column, bringing out a well-defined crustal block structure in SGT with individual highly resistive blocks showing correspondence to the geologically demarcated Salem, Madurai, and Trivandrum blocks. The 3-D model also brought out a well-defined major crustal conductor located in the northern half of the Madurai block. The electrical characteristics of this south dipping conductor and its close spatial correlation with two of the major structural elements, viz., Karur-Oddanchatram-Kodaikanal Shear Zone and Karur-Kamban-Painavu-Trichur Shear Zone, suggest that this conductive feature is closely linked to the subduction-collision tectonic processes in the SGT, and it is inferred that the Archean Dharwar craton/neoproterozoic SGT terrain boundary lies south of the Palghat-Cauvery shear zone. The results also showed that the Achankovil shear zone is characterized by a well-defined north dipping conductive feature. The resistive block adjoining this conductor on the southern side, representing the Trivandrum block, is shown to be downthrown along this north dipping crustal conductor relative to the Madurai block, suggesting a northward movement of Trivandrum block colliding against the Madurai block. The lithospheric upper mantle electrical structure of the SGT up to a depth of 100 km may be broadly divided into two distinctly different segments, viz., northern and southern segments. The northern lithospheric segment, over a major part, is characterized by a thick resistive upper mantle, while the southern one is characterized by a dominantly conductive medium suggesting a relatively thinned lithosphere in the southern segment.

Acoustic Observation of Living Organisms Reveals the Upper Limit of the Oxygen Minimum Zone

PubMed Central

Bertrand, Arnaud; Ballón, Michael; Chaigneau, Alexis

2010-01-01

Background Oxygen minimum zones (OMZs) are expanding in the World Ocean as a result of climate change and direct anthropogenic influence. OMZ expansion greatly affects biogeochemical processes and marine life, especially by constraining the vertical habitat of most marine organisms. Currently, monitoring the variability of the upper limit of the OMZs relies on time intensive sampling protocols, causing poor spatial resolution. Methodology/Principal Findings Using routine underwater acoustic observations of the vertical distribution of marine organisms, we propose a new method that allows determination of the upper limit of the OMZ with a high precision. Applied in the eastern South-Pacific, this original sampling technique provides high-resolution information on the depth of the upper OMZ allowing documentation of mesoscale and submesoscale features (e.g., eddies and filaments) that structure the upper ocean and the marine ecosystems. We also use this information to estimate the habitable volume for the world's most exploited fish, the Peruvian anchovy (Engraulis ringens). Conclusions/Significance This opportunistic method could be implemented on any vessel geared with multi-frequency echosounders to perform comprehensive high-resolution monitoring of the upper limit of the OMZ. Our approach is a novel way of studying the impact of physical processes on marine life and extracting valid information about the pelagic habitat and its spatial structure, a crucial aspect of Ecosystem-based Fisheries Management in the current context of climate change. PMID:20442791

Plateau subduction, intraslab seismicity and the Denali Volcanic Gap

NASA Astrophysics Data System (ADS)

Bostock, M. G.; Chuang, L. Y.; Wech, A.; Plourde, A. P.

2017-12-01

Tectonic tremors in Alaska (USA) are associated with subduction of the Yakutat plateau, but their origins are unclear due to lack of depth constraints. We have processed tremor recordings to extract low-frequency earthquakes (LFEs), and generated a set of six LFE waveform templates via iterative network matched filtering and stacking. The timing of impulsive P (compressional) wave and S (shear) wave arrivals on template waveforms places LFEs at 40-58 km depth, near the upper envelope of intraslab seismicity and immediately updip of increased levels of intraslab seismicity. S waves at near-epicentral distances display polarities consistent with shear slip on the plate boundary. We compare characteristics of LFEs, seismicity, and tectonic structures in central Alaska with those in warm subduction zones, and propose a new model for the region's unusual intraslab seismicity and the enigmatic Denali volcanic gap (i.e., an area of no volcanism where expected). We argue that fluids in the Yakutat plate are confined to its upper crust, and that shallow subduction leads to hydromechanical conditions at the slab interface in central Alaska akin to those in warm subduction zones where similar LFEs and tremor occur. These conditions lead to fluid expulsion at shallow depths, explaining strike-parallel alignment of tremor occurrence with the Denali volcanic gap. Moreover, the lack of double seismic zone and restriction of deep intraslab seismicity to a persistent low-velocity zone are simple consequences of anhydrous conditions prevailing in the lower crust and upper mantle of the Yakutat plate.

Plateau subduction, intraslab seismicity, and the Denali (Alaska) volcanic gap

USGS Publications Warehouse

Chuang, Lindsay Yuling; Bostock, Michael; Wech, Aaron; Plourde, Alexandre

2018-01-01

Tectonic tremors in Alaska (USA) are associated with subduction of the Yakutat plateau, but their origins are unclear due to lack of depth constraints. We have processed tremor recordings to extract low-frequency earthquakes (LFEs), and generated a set of six LFE waveform templates via iterative network matched filtering and stacking. The timing of impulsive P (compressional) wave and S (shear) wave arrivals on template waveforms places LFEs at 40–58 km depth, near the upper envelope of intraslab seismicity and immediately updip of increased levels of intraslab seismicity. S waves at near-epicentral distances display polarities consistent with shear slip on the plate boundary. We compare characteristics of LFEs, seismicity, and tectonic structures in central Alaska with those in warm subduction zones, and propose a new model for the region’s unusual intraslab seismicity and the enigmatic Denali volcanic gap (i.e., an area of no volcanism where expected). We argue that fluids in the Yakutat plate are confined to its upper crust, and that shallow subduction leads to hydromechanical conditions at the slab interface in central Alaska akin to those in warm subduction zones where similar LFEs and tremor occur. These conditions lead to fluid expulsion at shallow depths, explaining strike-parallel alignment of tremor occurrence with the Denali volcanic gap. Moreover, the lack of double seismic zone and restriction of deep intraslab seismicity to a persistent low-velocity zone are simple consequences of anhydrous conditions prevailing in the lower crust and upper mantle of the Yakutat plate.

Termination Proofs for String Rewriting Systems via Inverse Match-Bounds

NASA Technical Reports Server (NTRS)

Butler, Ricky (Technical Monitor); Geser, Alfons; Hofbauer, Dieter; Waldmann, Johannes

2004-01-01

Annotating a letter by a number, one can record information about its history during a reduction. A string rewriting system is called match-bounded if there is a global upper bound to these numbers. In earlier papers we established match-boundedness as a strong sufficient criterion for both termination and preservation of regular languages. We show now that the string rewriting system whose inverse (left and right hand sides exchanged) is match-bounded, also have exceptional properties, but slightly different ones. Inverse match-bounded systems effectively preserve context-free languages; their sets of normalized strings and their sets of immortal strings are effectively regular. These sets of strings can be used to decide the normalization, the termination and the uniform termination problems of inverse match-bounded systems. We also show that the termination problem is decidable in linear time, and that a certain strong reachability problem is deciable, thus solving two open problems of McNaughton's.

Models of Deformation of Uppermost Oceanic Lithosphere: Comparison of Crustal Flexure in the Blönduós Area, Northern Iceland, and Structure of East Pacific Rise Crust at Hess Deep

NASA Astrophysics Data System (ADS)

Horst, A. J.; Karson, J. A.; Varga, R. J.; Gee, J. S.

2007-12-01

Models of the internal structure of oceanic crust have been constructed from studies of ophiolites and from more recent observations of tectonic windows into the upper crust. Spreading rate and/or magma supply are the central variables that control ridge processes and the ultimate architecture of ocean crust. In addition to ophiolites, Iceland also provides an important analog to study mid-ocean ridge processes and structure. Flexure zones in Iceland characterize the structure of Tertiary-Recent lava flows, and are areas wherein lavas dip regionally inward toward the axis of one of several ~N/S-trending rift zones. These rift zones are interpreted to represent fossil spreading centers which were abandoned during a series of eastward-directed ridge jumps. In the Hildará area, north-central Iceland, the eastern side of a regional flexure is characterized by westward-dipping lavas, approximately 6-8 Ma, which are cut by east-dipping normal faults and dikes. The upper-crustal structure within this flexure zone from slow spread (~20 mm/yr) crust exhibits remarkable similarities to the structure of the upper crust created at a fast-spreading (110 mm/yr) segment of the East Pacific Rise (EPR) observed at Hess Deep. In this modern ocean setting, ~1 Ma crust is characterized by west-dipping lavas above consistently east-dipping (away from the EPR) dikes and dike-subparallel fault zones. In both locations, paleomagnetic and structural data indicate that west-dipping lavas and east-dipping dikes result from tectonic rotations. In addition, cross-cutting dike relationships demonstrate that dike intrusion occurred both during and after normal fault- related tilting. These data indicate that fault-controlled tilting was initiated within the narrow neovolcanic zone of the ridge and is not associated with off-axis processes. Lavas at magmatically robust ridges commonly flow away from elevated ridge-crests. Measurement of anisotropy of magnetic susceptibility (AMS) of the lavas from the flexure in Iceland suggests a mean flow direction to the northeast, that is, away from the fossil-ridge axis, demonstrating that the fossil spreading center from which the lavas were extruded was located to the west. Despite the distinct differences in spreading rates, the high magma supply in both environments resulted in a very similar upper crustal architecture.

Palaeozoic and Mesozoic tectonic implications of Central Afghanistan

NASA Astrophysics Data System (ADS)

Sliaupa, Saulius; Motuza, Gediminas

2017-04-01

The field and laboratory studies were carried out in Ghor Province situated in the central part of Afghanistan. It straddles juxtaposition of the Tajik (alternatively, North Afghanistan) and Farah Rod blocks separated by Band-e-Bayan zone. The recent studies indicate that Band-e-Bayan zone represents highly tectonised margin of the Tajik block (Motuza, Sliaupa, 2016). The Band-e-Bayan zone is the most representative in terms of sedimentary record. The subsidence trends and sediment lithologies suggest the passive margin setting during (Cambrian?) Ordovician to earliest Carboniferous times. A change to the foredeep setting is implied in middle Carboniferous through Early Permian; the large-thickness flysh-type sediments were derived from continental island arc provenance, as suggested by chemical composition of mudtstones. This stage can be correlated to the amalgamation of the Gondwana supercontinent. The new passive-margin stage can be inferred in the Band-e-Bayan zone and Tajik blocks in the Late Permian throughout the early Late Triassic that is likely related to breaking apart of Gondwana continent. A collisional event is suggested in latest Triassic, as seen in high-rate subsidence associating with dramatic change in litholgies, occurrence of volcanic rocks and granidoid intrusions. The continental volcanic island arc derived (based on geochemical indices) terrigens prevail at the base of Jurassic that were gradually replaced by carbonate platform in the Middle Jurassic pointing to cessation of the tectonic activity. A new tectonic episode (no deposition; and folding?) took place in the Tajik and Band-e-Bayan zone in Late Jurassic. The geological section of the Farah Rod block, situated to the south, is represented by Jurassic and Cretaceous sediments overlain by sporadic Cenozoic volcanic-sedimentary succession. The lower part of the Mesozoic succession is composed of terrigenic sediments giving way to upper Lower Cretaceous shallow water carbonates implying low tectonic regime. There was a break in sedimentation during the upper Cretaceous that is likely related to the Alpine orogenic event. It associated with some Upper Cretaceous magmatic activity (Debon et al., 1987). This event is reflected in the sedimentation pattern in the adjacent Band-e-Bayan zone and Tadjick block. The lower part of the Upper Cretaceous succession is composed of reddish terrigenic sediments. They are overlain by uppermost Cretaceous (and Danian) shallow marine sediments implying establishment of quiet tectonic conditions.

Dissolved organic carbon concentrations and compositions, and trihalomethane formation potentials in waters from agricultural peat soils, Sacramento-San Joaquin Delta, California; implications for drinking-water quality

USGS Publications Warehouse

Fujii, Roger; Ranalli, Anthony J.; Aiken, George R.; Bergamaschi, Brian A.

1998-01-01

Water exported from the Sacramento-San Joaquin River delta (Delta) is an important drinking-water source for more than 20 million people in California. At times, this water contains elevated concentrations of dissolved organic carbon and bromide, and exceeds the U.S. Environmental Protection Agency's maximum contaminant level for trihalomethanes of 0.100 milligrams per liter if chlorinated for drinking water. About 20 to 50 percent of the trihalomethane precursors to Delta waters originates from drainage water from peat soils on Delta islands. This report elucidates some of the factors and processes controlling and affecting the concentration and quality of dissolved organic carbon released from peat soils and relates the propensity of dissolved organic carbon to form trihalomethanes to its chemical composition.Soil water was sampled from near-surface, oxidized, well-decomposed peat soil (upper soil zone) and deeper, reduced, fibrous peat soil (lower soil zone) from one agricultural field in the west central Delta over 1 year. Concentrations of dissolved organic carbon in the upper soil zone were highly variable, with median concentrations ranging from 46.4 to 83.2 milligrams per liter. Concentrations of dissolved organic carbon in samples from the lower soil zone were much less variable and generally slightly higher than samples from the upper soil zone, with median concentrations ranging from 49.3 to 82.3 milligrams per liter. The dissolved organic carbon from the lower soil zone had significantly higher aromaticity (as measured by specific ultraviolet absorbance) and contained significantly greater amounts of aromatic humic substances (as measured by XAD resin fractionation and carbon-13 nuclear magnetic resonance analysis of XAD isolates) than the dissolved organic carbon from the upper soil zone. These results support the conclusion that more aromatic forms of dissolved organic carbon are produced under anaerobic conditions compared to aerobic conditions. Dissolved organic carbon concentration, trihalomethane formation potential, and ultraviolet absorbance were all highly correlated, showing that trihalomethane precursors increased with increasing dissolved organic carbon and ultraviolet absorbance for whole water samples. Contrary to the generally accepted conceptual model for trihalomethane formation that assumes that aromatic forms of carbon are primary precursors to trihalomethanes, results from this study indicate that dissolved organic carbon aromaticity appears unrelated to trihalomethane formation on a carbon-normalized basis. Thus, dissolved organic carbon aromaticity alone cannot fully explain or predict trihalomethane precursor content, and further investigation of aromatic and nonaromatic forms of carbon will be needed to better identify trihalomethane precursors.

Late Cretaceous base level lowering in Campanian and Maastrichtian depositional sequences, Kure Beach, North Carolina

USGS Publications Warehouse

Harris, W.B.; ,

2006-01-01

Campanian through Maastrichtian mixed carbonate and siliciclastic sediments in a 422 m continuous core drilled at Kure Beach, NC provide a record of sea-level change. Based on lithology and stratigraphy, depositional sequences are defined, and calcareous nannofossil zones and 87Sr/86Sr ratios and corresponding ages using the LOWESS Table determined. Campanian and Maastrichtian sediments comprise six depositional sequences. The oldest is Tar Heel 1 and contains calcareous nannofossils that indicate assignment to the upper part of Zones CC18a, CC18c and the lower part of CC19. 87Sr/86 Sr ratios indicate ages from 83.2 to 80.0 Ma or lower Campanian. Tar Heel II contains calcareous nannofossils that indicate assignment to the upper part of Zone CC 19 and CC20. 87Sr/86Sr ratios indicate ages from 78.0 to 76.3 Ma or middle Campanian. Donoho Creek I and II are thin and contain calcareous nannofossils referable to upper Zone CC21 and Zone CC22, and to CC23, respectively. The top of Donoho Creek II marks the Campanian-Maastrichtian boundary. Donoho Creek I 87Sr/86Sr ratios cluster into two groups, and provide ages from 78.0 to 76.2 Ma and 73.7 to 72.3 Ma, respectively. 87Sr/86Sr ratios in Donoho Creek II indicate ages from 71.4 to 69.6 Ma. Two Maastrichtian sequences are present; the lowermost Peedee I contains calcareous nannofossils that place it in Zones CC25a and CC25b. 87Sr/86Sr r ratios indicate an age from 69.3 to 66.9 Ma or late Maastrichtian. Peedee II is assigned to calcareous nannofossil Zone CC26a. 87Sr/86Sr ratios indicate ages from 66.4 to 65.2 Ma or late Maastrichtian. The four Campanian sequences correlate to three depositional sequences in New Jersey; the sequence boundary between upper Campanian Donoho Creek I and Donoho Creek II is not recognized in New Jersey. This boundary is interpreted to result from Gulf Stream impingement and subsequent erosion on the outer shelf. The two Maastrichtian sequences recognized in the Kure Beach core correlate to the two identified Maastrichtian sequences in New Jersey. These data support base-level lowering of sea-level during the Campanian-Maastrichtian, and suggest that the western margin of the North Atlantic may contain one of the best Late Cretaceous records of sea-level change.

Does lead affect microbial metabolism in aquifer sediments under different terminal electron accepting conditions?

USGS Publications Warehouse

Bradley, P.M.; Chapelle, F.H.; Vroblesky, D.A.

1993-01-01

In groundwater from a petroleum hydrocarbon-contaminated aquifer. Substantial accumulation of aliphatic organic acids occurred only in methanogenic microcosms, and only trace amounts of acetic acid were detected in sulfate-reducing microcosms. This pattern parallels field observations in which high organic acid concentrations were detected in methanogenic zones, but only low concentrations of acetic acid were detected in sulfate-reducing zones. -from Authors

Protocol for multiple node network

NASA Technical Reports Server (NTRS)

Kirkham, Harold (Inventor)

1995-01-01

The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

Protocol for multiple node network

NASA Technical Reports Server (NTRS)

Kirkham, Harold (Inventor)

1994-01-01

The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

Experimental study on the heat transfer characteristics of waste printed circuit boards pyrolysis.

PubMed

Ma, Hongting; Du, Na; Lin, Xueyin; Li, Chen; Lai, Junwen; Li, Zihao

2018-08-15

In order to study the appropriate and advanced technology for recycling waste printed circuit boards (PCBs), a fixed bed pyrolysis device with stirring function has been designed and developed. The effect of rotating speed on the temperature distribution and mass change in the pyrolysis process of FR-4 PCB has been analyzed. The heat transfer and pyrolysis characteristics of different granular layers with and without stirring have been investigated. The results indicate that the stirring can change the main way of heat transfer from conduction to convection in the PCB layers. As the increase of rotating speed, the temperature rising rate of material at the bottom of the pyrolysis furnace gradually decreases, while the heating rate is increasing at the upper layer, and the temperature difference between the upper and bottom layers is gradually reduced. When the rotating speed varies from 0r/min to 18r/min, the weight loss of the material increases from 3.97% to 6.76%, and the overall pyrolysis degree is improved. During the pyrolysis process, the material layer can be divided into three zones along the vertical direction, namely complete pyrolysis zone, partial pyrolysis zone and non-pyrolysis zone. As the rotating speed is 0r/min, the thickness of each zones is 6cm, 6cm and 3cm, respectively. However, when the rotating speed is increased to 18r/min, the non-pyrolysis zone disappears, and the thickness of complete pyrolysis zone and partial pyrolysis zone increase to 9cm and 6cm, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

The north-subducting Rheic Ocean during the Devonian: consequences for the Rhenohercynian ore sites

NASA Astrophysics Data System (ADS)

von Raumer, Jürgen F.; Nesbor, Heinz-Dieter; Stampfli, Gérard M.

2017-10-01

Base metal mining in the Rhenohercynian Zone has a long history. Middle-Upper Devonian to Lower Carboniferous sediment-hosted massive sulfide deposits (SHMS), volcanic-hosted massive sulfide deposits (VHMS) and Lahn-Dill-type iron, and base metal ores occur at several sites in the Rhenohercynian Zone that stretches from the South Portuguese Zone, through the Lizard area, the Rhenish Massif and the Harz Mountain to the Moravo-Silesian Zone of SW Bohemia. During Devonian to Early Carboniferous times, the Rhenohercynian Zone is seen as an evolving rift system developed on subsiding shelf areas of the Old Red continent. A reappraisal of the geotectonic setting of these ore deposits is proposed. The Middle-Upper Devonian to Early Carboniferous time period was characterized by detrital sedimentation, continental intraplate and subduction-related volcanism. The large shelf of the Devonian Old Red continent was the place of thermal subsidence with contemporaneous mobilization of rising thermal fluids along activated Early Devonian growth faults. Hydrothermal brines equilibrated with the basement and overlying Middle-Upper Devonian detrital deposits forming the SHMS deposits in the southern part of the Pyrite Belt, in the Rhenish Massif and in the Harz areas. Volcanic-hosted massive sulfide deposits (VHMS) formed in the more eastern localities of the Rhenohercynian domain. In contrast, since the Tournaisian period of ore formation, dominant pull-apart triggered magmatic emplacement of acidic rocks, and their metasomatic replacement in the apical zones of felsic domes and sediments in the northern part of the Iberian Pyrite belt, thus changing the general conditions of ore precipitation. This two-step evolution is thought to be controlled by syn- to post-tectonic phases in the Variscan framework, specifically by the transition of geotectonic setting dominated by crustal extension to a one characterized by the subduction of the supposed northern slab of the Rheic Ocean preceding the general Late Variscan crustal shortening and oroclinal bending.

Ambient noise tomography reveals upper crustal structure of Icelandic rifts

NASA Astrophysics Data System (ADS)

Green, Robert G.; Priestley, Keith F.; White, Robert S.

2017-05-01

The structure of oceanic spreading centres and subsurface melt distribution within newly formed crust is largely understood from marine seismic experiments. In Iceland, however, sub-aerial rift elevation allows both accurate surface mapping and the installation of large broadband seismic arrays. We present a study using ambient noise Rayleigh wave tomography to image the volcanic spreading centres across Iceland. Our high resolution model images a continuous band of low seismic velocities, parallelling all three segments of the branched rift in Iceland. The upper 10 km contains strong velocity variations, with shear wave velocities 0.5 km s-1 faster in the older non-volcanically active regions compared to the active rifts. Slow velocities correlate very closely with geological surface mapping, with contours of the anomalies parallelling the edges of the neo-volcanic zones. The low-velocity band extends to the full 50 km width of the neo-volcanic zones, demonstrating a significant contrast with the narrow (8 km wide) magmatic zone seen at fast spreading ridges, where the rate of melt supply is similarly high. Within the seismically slow rift band, the lowest velocity cores of the anomalies occur above the centre of the mantle plume under the Vatnajökull icecap, and in the Eastern Volcanic Zone under the central volcano Katla. This suggests localisation of melt accumulation at these specific volcanic centres, demonstrating variability in melt supply into the shallow crust along the rift axis. Shear velocity inversions with depth show that the strongest velocity contrasts are found in the upper 8 km, and show a slight depression in the shear velocity through the mid crust (10-20 km) in the rifts. Our model also shows less intensity to the slow rift anomaly in the Western Volcanic Zone, supporting the notion that rift activity here is decreasing as the ridge jumps to the Eastern Volcanic Zone.

Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile.

PubMed

Parris, Darren J; Ganesh, Sangita; Edgcomb, Virginia P; DeLong, Edward F; Stewart, Frank J

2014-01-01

Molecular surveys are revealing diverse eukaryotic assemblages in oxygen-limited ocean waters. These communities may play pivotal ecological roles through autotrophy, feeding, and a wide range of symbiotic associations with prokaryotes. We used 18S rRNA gene sequencing to provide the first snapshot of pelagic microeukaryotic community structure in two cellular size fractions (0.2-1.6 μm, >1.6 μm) from seven depths through the anoxic oxygen minimum zone (OMZ) off northern Chile. Sequencing of >154,000 amplicons revealed contrasting patterns of phylogenetic diversity across size fractions and depths. Protist and total eukaryote diversity in the >1.6 μm fraction peaked at the chlorophyll maximum in the upper photic zone before declining by ~50% in the OMZ. In contrast, diversity in the 0.2-1.6 μm fraction, though also elevated in the upper photic zone, increased four-fold from the lower oxycline to a maximum at the anoxic OMZ core. Dinoflagellates of the Dinophyceae and endosymbiotic Syndiniales clades dominated the protist assemblage at all depths (~40-70% of sequences). Other protist groups varied with depth, with the anoxic zone community of the larger size fraction enriched in euglenozoan flagellates and acantharean radiolarians (up to 18 and 40% of all sequences, respectively). The OMZ 0.2-1.6 μm fraction was dominated (11-99%) by Syndiniales, which exhibited depth-specific variation in composition and total richness despite uniform oxygen conditions. Metazoan sequences, though confined primarily to the 1.6 μm fraction above the OMZ, were also detected within the anoxic zone where groups such as copepods increased in abundance relative to the oxycline and upper OMZ. These data, compared to those from other low-oxygen sites, reveal variation in OMZ microeukaryote composition, helping to identify clades with potential adaptations to oxygen-depletion.

Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile

PubMed Central

Parris, Darren J.; Ganesh, Sangita; Edgcomb, Virginia P.; DeLong, Edward F.; Stewart, Frank J.

2014-01-01

Molecular surveys are revealing diverse eukaryotic assemblages in oxygen-limited ocean waters. These communities may play pivotal ecological roles through autotrophy, feeding, and a wide range of symbiotic associations with prokaryotes. We used 18S rRNA gene sequencing to provide the first snapshot of pelagic microeukaryotic community structure in two cellular size fractions (0.2–1.6 μm, >1.6 μm) from seven depths through the anoxic oxygen minimum zone (OMZ) off northern Chile. Sequencing of >154,000 amplicons revealed contrasting patterns of phylogenetic diversity across size fractions and depths. Protist and total eukaryote diversity in the >1.6 μm fraction peaked at the chlorophyll maximum in the upper photic zone before declining by ~50% in the OMZ. In contrast, diversity in the 0.2–1.6 μm fraction, though also elevated in the upper photic zone, increased four-fold from the lower oxycline to a maximum at the anoxic OMZ core. Dinoflagellates of the Dinophyceae and endosymbiotic Syndiniales clades dominated the protist assemblage at all depths (~40–70% of sequences). Other protist groups varied with depth, with the anoxic zone community of the larger size fraction enriched in euglenozoan flagellates and acantharean radiolarians (up to 18 and 40% of all sequences, respectively). The OMZ 0.2–1.6 μm fraction was dominated (11–99%) by Syndiniales, which exhibited depth-specific variation in composition and total richness despite uniform oxygen conditions. Metazoan sequences, though confined primarily to the 1.6 μm fraction above the OMZ, were also detected within the anoxic zone where groups such as copepods increased in abundance relative to the oxycline and upper OMZ. These data, compared to those from other low-oxygen sites, reveal variation in OMZ microeukaryote composition, helping to identify clades with potential adaptations to oxygen-depletion. PMID:25389417

Seismic reflection imaging of two megathrust shear zones in the northern Cascadia subduction zone.

PubMed

Calvert, Andrew J

2004-03-11

At convergent continental margins, the relative motion between the subducting oceanic plate and the overriding continent is usually accommodated by movement along a single, thin interface known as a megathrust. Great thrust earthquakes occur on the shallow part of this interface where the two plates are locked together. Earthquakes of lower magnitude occur within the underlying oceanic plate, and have been linked to geochemical dehydration reactions caused by the plate's descent. Here I present deep seismic reflection data from the northern Cascadia subduction zone that show that the inter-plate boundary is up to 16 km thick and comprises two megathrust shear zones that bound a >5-km-thick, approximately 110-km-wide region of imbricated crustal rocks. Earthquakes within the subducting plate occur predominantly in two geographic bands where the dip of the plate is inferred to increase as it is forced around the edges of the imbricated inter-plate boundary zone. This implies that seismicity in the subducting slab is controlled primarily by deformation in the upper part of the plate. Slip on the shallower megathrust shear zone, which may occur by aseismic slow slip, will transport crustal rocks into the upper mantle above the subducting oceanic plate and may, in part, provide an explanation for the unusually low seismic wave speeds that are observed there.

'One physical system': Tansley's ecosystem as Earth's critical zone.

PubMed

Richter, Daniel deB; Billings, Sharon A

2015-05-01

Integrative concepts of the biosphere, ecosystem, biogeocenosis and, recently, Earth's critical zone embrace scientific disciplines that link matter, energy and organisms in a systems-level understanding of our remarkable planet. Here, we assert the congruence of Tansley's (1935) venerable ecosystem concept of 'one physical system' with Earth science's critical zone. Ecosystems and critical zones are congruent across spatial-temporal scales from vegetation-clad weathering profiles and hillslopes, small catchments, landscapes, river basins, continents, to Earth's whole terrestrial surface. What may be less obvious is congruence in the vertical dimension. We use ecosystem metabolism to argue that full accounting of photosynthetically fixed carbon includes respiratory CO₂ and carbonic acid that propagate to the base of the critical zone itself. Although a small fraction of respiration, the downward diffusion of CO₂ helps determine rates of soil formation and, ultimately, ecosystem evolution and resilience. Because life in the upper portions of terrestrial ecosystems significantly affects biogeochemistry throughout weathering profiles, the lower boundaries of most terrestrial ecosystems have been demarcated at depths too shallow to permit a complete understanding of ecosystem structure and function. Opportunities abound to explore connections between upper and lower components of critical-zone ecosystems, between soils and streams in watersheds, and between plant-derived CO₂ and deep microbial communities and mineral weathering. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Structural Mapping Along the Central San Andreas Fault-zone Using Airborne Electromagnetics

NASA Astrophysics Data System (ADS)

Zamudio, K. D.; Bedrosian, P.; Ball, L. B.

2017-12-01

Investigations of active fault zones typically focus on either surface expressions or the associated seismogenic zones. However, the largely aseismic upper kilometer can hold significant insight into fault-zone architecture, strain partitioning, and fault-zone permeability. Geophysical imaging of the first kilometer provides a link between surface fault mapping and seismically-defined fault zones and is particularly important in geologically complex regions with limited surface exposure. Additionally, near surface imaging can provide insight into the impact of faulting on the hydrogeology of the critical zone. Airborne electromagnetic (AEM) methods offer a unique opportunity to collect a spatially-large, detailed dataset in a matter of days, and are used to constrain subsurface resistivity to depths of 500 meters or more. We present initial results from an AEM survey flown over a 60 kilometer long segment of the central San Andreas Fault (SAF). The survey is centered near Parkfield, California, the site of the SAFOD drillhole, which marks the transition between a creeping fault segment to the north and a locked zone to the south. Cross sections with a depth of investigation up to approximately 500 meters highlight the complex Tertiary and Mesozoic geology that is dismembered by the SAF system. Numerous fault-parallel structures are imaged across a more than 10 kilometer wide zone centered on the surface trace. Many of these features can be related to faults and folds within Plio-Miocene sedimentary rocks found on both sides of the fault. Northeast of the fault, rocks of the Mesozoic Franciscan and Great Valley complexes are extremely heterogeneous, with highly resistive volcanic rocks within a more conductive background. The upper 300 meters of a prominent fault-zone conductor, previously imaged to 1-3 kilometers depth by magnetotellurics, is restricted to a 20 kilometer long segment of the fault, but is up to 4 kilometers wide in places. Elevated fault-zone conductivity may be related to damage within the fault zone, Miocene marine shales, or some combination of the two.

Marine forearc extension in the Hikurangi Margin: New insights from high-resolution 3D seismic data

NASA Astrophysics Data System (ADS)

Böttner, Christoph; Gross, Felix; Geersen, Jacob; Mountjoy, Joshu; Crutchley, Gareth; Krastel, Sebastian

2017-04-01

In subduction zones upper-plate normal faults have long been considered a tectonic feature primarily associated with erosive margins. However, increasing data coverage has proven that similar features also occur in accretionary margins, such as Cascadia, Makran, Nankai or Central Chile, where kinematics are dominated by compression. Considering their wide distribution there is, without doubt, a significant lack of qualitative and quantitative knowledge regarding the role and importance of normal faults and zones of extension for the seismotectonic evolution of accretionary margins. We use a high-resolution 3D P-Cable seismic volume from the Hikurangi Margin acquired in 2014 to analyze the spatial distribution and mechanisms of upper-plate normal faulting. The study area is located at the upper continental slope in the area of the Tuaheni landslide complex. In detail we aim to (1) map the spatial distribution of normal faults and characterize their vertical throws, strike directions, and dip angles; (2) investigate their possible influence on fluid migration in an area, where gas hydrates are present; (3) discuss the mechanisms that may cause extension of the upper-slope in the study area. Beneath the Tuaheni Landslide Complex we mapped about 200 normal faults. All faults have low displacements (<15 m) and dip at high (> 65°) angles. About 71% of the faults dip landward. We found two main strike directions, with the majority of faults striking 350-10°, parallel to the deformation front. A second group of faults strikes 40-60°. The faults crosscut the BSR, which indicates the base of the gas hydrate zone. In combination with seismically imaged bright-spots and pull-up structures, this indicates that the normal faults effectively transport fluids vertically across the base of the gas hydrate zone. Localized uplift, as indicated by the presence of the Tuaheni Ridge, might support normal faulting in the study area. In addition, different subduction rates across the margin may also favor extension between the segments. Future work will help to further untangle the mechanisms that cause extension of the upper continental slope.

The Sorong Fault Zone, Indonesia: Mapping a Fault Zone Offshore

NASA Astrophysics Data System (ADS)

Melia, S.; Hall, R.

2017-12-01

The Sorong Fault Zone is a left-lateral strike-slip fault zone in eastern Indonesia, extending westwards from the Bird's Head peninsula of West Papua towards Sulawesi. It is the result of interactions between the Pacific, Caroline, Philippine Sea, and Australian Plates and much of it is offshore. Previous research on the fault zone has been limited by the low resolution of available data offshore, leading to debates over the extent, location, and timing of movements, and the tectonic evolution of eastern Indonesia. Different studies have shown it north of the Sula Islands, truncated south of Halmahera, continuing to Sulawesi, or splaying into a horsetail fan of smaller faults. Recently acquired high resolution multibeam bathymetry of the seafloor (with a resolution of 15-25 meters), and 2D seismic lines, provide the opportunity to trace the fault offshore. The position of different strands can be identified. On land, SRTM topography shows that in the northern Bird's Head the fault zone is characterised by closely spaced E-W trending faults. NW of the Bird's Head offshore there is a fold and thrust belt which terminates some strands. To the west of the Bird's Head offshore the fault zone diverges into multiple strands trending ENE-WSW. Regions of Riedel shearing are evident west of the Bird's Head, indicating sinistral strike-slip motion. Further west, the ENE-WSW trending faults turn to an E-W trend and there are at least three fault zones situated immediately south of Halmahera, north of the Sula Islands, and between the islands of Sanana and Mangole where the fault system terminates in horsetail strands. South of the Sula islands some former normal faults at the continent-ocean boundary with the North Banda Sea are being reactivated as strike-slip faults. The fault zone does not currently reach Sulawesi. The new fault map differs from previous interpretations concerning the location, age and significance of different parts of the Sorong Fault Zone. Kinematic analysis is underway to give a fresh understanding of the tectonic evolution of this complex zone of faulting and plate interaction.

5. EAST ELEVATION (OFFICE BLOCK), DETAIL SHOWING DECORATIVE PILASTERS AND ...

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

5. EAST ELEVATION (OFFICE BLOCK), DETAIL SHOWING DECORATIVE PILASTERS AND STYLIZED EGG-AND-DART DECORATION AROUND WINDOWS OF UPPER FLOORS - Delaware, Lackawanna & Western Railroad & Ferry Terminal, Hudson Place, Hoboken, Hudson County, NJ

Geologic framework and hydrostratigraphy of the Edwards and Trinity aquifers within northern Bexar and Comal Counties, Texas

USGS Publications Warehouse

Clark, Allan K.; Golab, James A.; Morris, Robert R.

2016-11-28

During 2014–16, the U.S. Geological Survey, in cooperation with the Edwards Aquifer Authority, documented the geologic framework and hydrostratigraphy of the Edwards and Trinity aquifers within northern Bexar and Comal Counties, Texas. The Edwards and Trinity aquifers are major sources of water for agriculture, industry, and urban and rural communities in south-central Texas. Both the Edwards and Trinity are classified as major aquifers by the State of Texas.The purpose of this report is to present the geologic framework and hydrostratigraphy of the Edwards and Trinity aquifers within northern Bexar and Comal Counties, Tex. The report includes a detailed 1:24,000-scale hydrostratigraphic map, names, and descriptions of the geology and hydrostratigraphic units (HSUs) in the study area.The scope of the report is focused on geologic framework and hydrostratigraphy of the outcrops and hydrostratigraphy of the Edwards and Trinity aquifers within northern Bexar and Comal Counties, Tex. In addition, parts of the adjacent upper confining unit to the Edwards aquifer are included.The study area, approximately 866 square miles, is within the outcrops of the Edwards and Trinity aquifers and overlying confining units (Washita, Eagle Ford, Austin, and Taylor Groups) in northern Bexar and Comal Counties, Tex. The rocks within the study area are sedimentary and range in age from Early to Late Cretaceous. The Miocene-age Balcones fault zone is the primary structural feature within the study area. The fault zone is an extensional system of faults that generally trends southwest to northeast in south-central Texas. The faults have normal throw, are en echelon, and are mostly downthrown to the southeast.The Early Cretaceous Edwards Group rocks were deposited in an open marine to supratidal flats environment during two marine transgressions. The Edwards Group is composed of the Kainer and Person Formations. Following tectonic uplift, subaerial exposure, and erosion near the end of Early Cretaceous time, the area of present-day south-central Texas was again submerged during the Late Cretaceous by a marine transgression resulting in deposition of the Georgetown Formation of the Washita Group.The Early Cretaceous Edwards Group, which overlies the Trinity Group, is composed of mudstone to boundstone, dolomitic limestone, argillaceous limestone, evaporite, shale, and chert. The Kainer Formation is subdivided into (bottom to top) the basal nodular, dolomitic, Kirschberg Evaporite, and grainstone members. The Person Formation is subdivided into (bottom to top) the regional dense, leached and collapsed (undivided), and cyclic and marine (undivided) members.Hydrostratigraphically the rocks exposed in the study area represent a section of the upper confining unit to the Edwards aquifer, the Edwards aquifer, the upper zone of the Trinity aquifer, and the middle zone of the Trinity aquifer. The Pecan Gap Formation (Taylor Group), Austin Group, Eagle Ford Group, Buda Limestone, and Del Rio Clay are generally considered to be the upper confining unit to the Edwards aquifer.The Edwards aquifer was subdivided into HSUs I to VIII. The Georgetown Formation of the Washita Group contains HSU I. The Person Formation of the Edwards Group contains HSUs II (cyclic and marine members [Kpcm], undivided), III (leached and collapsed members [Kplc,] undivided), and IV (regional dense member [Kprd]), and the Kainer Formation of the Edwards Group contains HSUs V (grainstone member [Kkg]), VI (Kirschberg Evaporite Member [Kkke]), VII (dolomitic member [Kkd]), and VIII (basal nodular member [Kkbn]).The Trinity aquifer is separated into upper, middle, and lower aquifer units (hereinafter referred to as “zones”). The upper zone of the Trinity aquifer is in the upper member of the Glen Rose Limestone. The middle zone of the Trinity aquifer is formed in the lower member of the Glen Rose Limestone, Hensell Sand, and Cow Creek Limestone. The regionally extensive Hammett Shale forms a confining unit between the middle and lower zones of the Trinity aquifer. The lower zone of the Trinity aquifer consists of the Sligo and Hosston Formations, which do not crop out in the study area.The upper zone of the Trinity aquifer is subdivided into five informal HSUs (top to bottom): cavernous, Camp Bullis, upper evaporite, fossiliferous, and lower evaporite. The middle zone of the Trinity aquifer is composed of the (top to bottom) Bulverde, Little Blanco, Twin Sisters, Doeppenschmidt, Rust, Honey Creek, Hensell, and Cow Creek HSUs. The underlying Hammett HSU is a regional confining unit between the middle and lower zones of the Trinity aquifer. The lower zone of the Trinity aquifer is not exposed in the study area.Groundwater recharge and flow paths in the study area are influenced not only by the hydrostratigraphic characteristics of the individual HSUs but also by faults and fractures and geologic structure. Faulting associated with the Balcones fault zone (1) might affect groundwater flow paths by forming a barrier to flow that results in water moving parallel to the fault plane, (2) might affect groundwater flow paths by increasing flow across the fault because of fracturing and juxtaposing porous and permeable units, or (3) might have no effect on the groundwater flow paths.The hydrologic connection between the Edwards and Trinity aquifers and the various HSUs is complex. The complexity of the aquifer system is a combination of the original depositional history, bioturbation, primary and secondary porosity, diagenesis, and fracturing of the area from faulting. All of these factors have resulted in development of modified porosity, permeability, and transmissivity within and between the aquifers. Faulting produced highly fractured areas that have allowed for rapid infiltration of water and subsequently formed solutionally enhanced fractures, bedding planes, channels, and caves that are highly permeable and transmissive. The juxtaposition resulting from faulting has resulted in areas of interconnectedness between the Edwards and Trinity aquifers and the various HSUs that form the aquifers.

Upper crustal densities derived from sea floor gravity measurements: Northern Juan De Fuca Ridge

USGS Publications Warehouse

Holmes, Mark L.; Johnson, H. Paul

1993-01-01

A transect of sea floor gravity stations has been analyzed to determine upper crustal densities on the Endeavour segment of the northern Juan de Fuca Ridge. Data were obtained using ALVIN along a corridor perpendicular to the axis of spreading, over crustal ages from 0 to 800,000 years. Calculated elevation factors from the gravity data show an abrupt increase in density with age (distance) for the upper 200 m of crust. This density change is interpreted as a systematic reduction in bulk porosity of the upper crustal section, from 23% for the axial ridge to 10% for the off-axis flanking ridges. The porosity decrease is attributed to the collapse and filling of large-scale voids as the abyssal hills move out of the crustal formation zone. Forward modeling of a plausible density structure for the near-axis region agrees with the observed anomaly data only if the model includes narrow, along-strike, low-density regions adjacent to both inner and outer flanks of the abyssal hills. The required low density zones could be regions of systematic upper crustal fracturing and faulting that were mapped by submersible observers and side-scan sonar images, and whose presence was suggested by the distribution of heat flow data in the same area.

Revised hydrogeologic framework of the Floridan aquifer system in the northern coastal area of Georgia and adjacent parts of South Carolina

USGS Publications Warehouse

Williams, Lester J.; Gill, Harold E.

2010-01-01

The hydrogeologic framework for the Floridan aquifer system has been revised for eight northern coastal counties in Georgia and five coastal counties in South Carolina by incorporating new borehole geophysical and flowmeter log data collected during previous investigations. Selected well logs were compiled and analyzed to determine the vertical and horizontal continuity of permeable zones that make up the Upper and Lower Floridan aquifers and to define more precisely the thickness of confining beds that separate these aquifers. The updated framework generally conforms to the original framework established by the U.S. Geological Survey in the 1980s except for adjustments made to the internal boundaries of the Upper and Lower Floridan aquifers and the individual permeable zones that compose these aquifers. The revised boundaries of the Floridan aquifer system were mapped by taking into account results from local studies and regional correlations of geologic and hydrogeologic units. Because the revised framework does not match the previous regional framework along all edges, additional work will be needed to expand the framework into adjacent areas. The Floridan aquifer system in the northern coastal region of Georgia and parts of South Carolina can be divided into the Upper and Lower Floridan aquifers, which are separated by a middle confining unit of relatively lower permeability. The Upper Floridan aquifer includes permeable and hydraulically connected carbonate rocks of Oligocene and upper Eocene age that represent the most transmissive part of the aquifer system. The middle confining unit consists of low permeability carbonate rocks that lie within the lower part of the upper Eocene in Beaufort and Jasper Counties, South Carolina, and within the upper to middle parts of the middle Eocene elsewhere. Locally, the middle confining unit contains thin zones that have moderate to high permeability and can produce water to wells that tap them. The Lower Floridan aquifer includes all permeable strata that lie below the middle confining unit and above the base of the aquifer system. Beneath Hilton Head Island, South Carolina, the middle Floridan aquifer is now included as part of the Lower Floridan aquifer. The base of the Floridan aquifer system generally is located at the top of lower Eocene rocks in Georgia and the top of Paleocene rocks in South Carolina. The Upper and Lower Floridan aquifers are interconnected to varying degrees depending on the thickness and permeability of the middle confining unit that separates these aquifers. In most places, hydraulic head differences between the two aquifers range from a few inches to a few feet or more. Monitoring at several vertically clustered well-point sites where wells were set at different depths in the aquifer revealed variations in the degree of hydraulic separation with depth. In general, the head separation between the Upper and Lower Floridan aquifers increases with depth, which indicates that the deeper zones are more hydraulically separated than the shallower parts of the Lower Floridan aquifer.

ApoER2 Controls Not Only Neuronal Migration in the Intermediate Zone But Also Termination of Migration in the Developing Cerebral Cortex.

PubMed

Hirota, Yuki; Kubo, Ken-Ichiro; Fujino, Takahiro; Yamamoto, Tokuo T; Nakajima, Kazunori

2018-01-01

Neuronal migration contributes to the establishment of mammalian brain. The extracellular protein Reelin sends signals to various downstream molecules by binding to its receptors, the apolipoprotein E receptor 2 (ApoER2) and very low-density lipoprotein receptor and exerts essential roles in the neuronal migration and formation of the layered neocortex. However, the cellular and molecular functions of Reelin signaling in the cortical development are not yet fully understood. Here, to gain insight into the role of Reelin signaling during cortical development, we examined the migratory behavior of Apoer2-deficient neurons in the developing brain. Stage-specific labeling of newborn neurons revealed that the neurons ectopically invaded the marginal zone (MZ) and that neuronal migration of both early- and late-born neurons was disrupted in the intermediate zone (IZ) in the Apoer2 KO mice. Rescue experiments showed that ApoER2 functions both in cell-autonomous and noncell-autonomous manners, that Rap1, integrin, and Akt are involved in the termination of migration beneath the MZ, and that Akt also controls neuronal migration in the IZ downstream of ApoER2. These data indicate that ApoER2 controls multiple processes in neuronal migration, including the early stage of radial migration and termination of migration beneath the MZ in the developing neocortex. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

An adaptive reentry guidance method considering the influence of blackout zone

NASA Astrophysics Data System (ADS)

Wu, Yu; Yao, Jianyao; Qu, Xiangju

2018-01-01

Reentry guidance has been researched as a popular topic because it is critical for a successful flight. In view that the existing guidance methods do not take into account the accumulated navigation error of Inertial Navigation System (INS) in the blackout zone, in this paper, an adaptive reentry guidance method is proposed to obtain the optimal reentry trajectory quickly with the target of minimum aerodynamic heating rate. The terminal error in position and attitude can be also reduced with the proposed method. In this method, the whole reentry guidance task is divided into two phases, i.e., the trajectory updating phase and the trajectory planning phase. In the first phase, the idea of model predictive control (MPC) is used, and the receding optimization procedure ensures the optimal trajectory in the next few seconds. In the trajectory planning phase, after the vehicle has flown out of the blackout zone, the optimal reentry trajectory is obtained by online planning to adapt to the navigation information. An effective swarm intelligence algorithm, i.e. pigeon inspired optimization (PIO) algorithm, is applied to obtain the optimal reentry trajectory in both of the two phases. Compared to the trajectory updating method, the proposed method can reduce the terminal error by about 30% considering both the position and attitude, especially, the terminal error of height has almost been eliminated. Besides, the PIO algorithm performs better than the particle swarm optimization (PSO) algorithm both in the trajectory updating phase and the trajectory planning phases.

76 FR 38975 - Safety Zone; Upper Mississippi River, Mile 856.0 to 855.0, Minneapolis, MN

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-05

... through July 24, 2011, World Sports and Marketing will sponsor the U.S. Wakeboard Nationals between Mile... INFORMATION CONTACT: If you have questions on this temporary rule, call or e-mail Chief Petty Officer Bryan Klostermeyer, Sector Upper Mississippi River Response Department at telephone (314) 269-2566, e-mail Bryan.K...

Ultrastructural identification of noradrenergic nerve terminals and vasopressin-containing neurons of the paraventricular nucleus in the same thin section.

PubMed

Silverman, A J; Hou-Yu, A; Oldfield, B J

1983-09-01

Since many peptidergic cell groups receive a diverse and complex monoaminergic innervation, we have developed a double-label procedure to visualize a peptide and a catecholamine in the same ultrathin section. Radiolabeled norepinephrine (NE) is applied locally and its reuptake into NE terminals is demonstrated by ultrastructural radioautography. Controls in this and other studies demonstrate that the NE labels only NE (and possibly epinephrine) terminals and not dopaminergic or serotonergic terminals. In the same tissue, vasopressin is localized by immunocytochemistry on unembedded sections that are subsequently embedded in epoxy resins for thin sectioning. The procedure as described here shows that NE terminals in the periventricular zone of the paraventricular nucleus of the hypothalamus innervate both vasopressin-positive and vasopressin-negative structures. This technique is useful in determining the chemical connectivity of the hypothalamus.

Dopamine D1 and D2 Receptor Immunoreactivities in the Arcuate-Median Eminence Complex and their Link to the Tubero-Infundibular Dopamine Neurons

PubMed Central

Romero-Fernandez, W.; Borroto-Escuela, D.O.; Vargas-Barroso, V.; Narváez, M.; Di Palma, M.; Agnati, L.F.; Sahd, J. Larriva

2014-01-01

Dopamine D1 and D2 receptor immunohistochemistry and Golgi techniques were used to study the structure of the adult rat arcuate-median eminence complex, and determine the distribution of the dopamine D1 and D2 receptor immunoreactivities therein, particularly in relation to the tubero-infundibular dopamine neurons. Punctate dopamine D1 and D2 receptor immunoreactivities, likely located on nerve terminals, were enriched in the lateral palisade zone built up of nerve terminals, while the densities were low to modest in the medial palisade zone. A codistribution of dopamine D1 receptor or dopamine D2 receptor immunoreactive puncta with tyrosine hydroxylase immunoreactive nerve terminals was demonstrated in the external layer. Dopamine D1 receptor but not dopamine D2 receptor immnunoreactivites nerve cell bodies were found in the ventromedial part of the arcuate nucleus and in the lateral part of the internal layer of the median eminence forming a continuous cell mass presumably representing neuropeptide Y immunoreactive nerve cell bodies. The major arcuate dopamine/ tyrosine hydroxylase nerve cell group was found in the dorsomedial part. A large number of tyrosine hydroxylase immunoreactive nerve cell bodies in this region demonstrated punctate dopamine D1 receptor immunoreactivity but only a few presented dopamine D2 receptor immunoreactivity which were mainly found in a substantial number of tyrosine hydroxylase cell bodies of the ventral periventricular hypothalamic nucleus, also belonging to the tuberoinfundibular dopamine neurons. Structural evidence for projections of the arcuate nerve cells into the median eminence was also obtained. Distal axons formed horizontal axons in the internal layer issuing a variable number of collaterals classified into single or multiple strands located in the external layer increasing our understanding of the dopamine nerve terminal networks in this region. Dopamine D1 and D2 receptors may therefore directly and differentially modulate the activity and/or Dopamine synthesis of substantial numbers of tubero-infundibular dopamine neurons at the somatic and terminal level. The immunohistochemical work also gives support to the view that dopamine D1 receptors and/or dopamine D2 receptors in the lateral palisade zone by mediating dopamine volume transmission may contribute to the inhibition of luteinizing hormone releasing hormone release from nerve terminals in this region. PMID:25308843

Dopamine D1 and D2 receptor immunoreactivities in the arcuate-median eminence complex and their link to the tubero-infundibular dopamine neurons.

PubMed

Romero-Fernandez, W; Borroto-Escuela, D O; Vargas-Barroso, V; Narváez, M; Di Palma, M; Agnati, L F; Larriva Sahd, J; Fuxe, K

2014-07-18

Dopamine D1 and D2 receptor immunohistochemistry and Golgi techniques were used to study the structure of the adult rat arcuate-median eminence complex, and determine the distribution of the dopamine D1 and D2 receptor immunoreactivities therein, particularly in relation to the tubero-infundibular dopamine neurons. Punctate dopamine D1 and D2 receptor immunoreactivities, likely located on nerve terminals, were enriched in the lateral palisade zone built up of nerve terminals, while the densities were low to modest in the medial palisade zone. A codistribution of dopamine D1 receptor or dopamine D2 receptor immunoreactive puncta with tyrosine hydroxylase immunoreactive nerve terminals was demonstrated in the external layer. Dopamine D1 receptor but not dopamine D2 receptor immnunoreactivites nerve cell bodies were found in the ventromedial part of the arcuate nucleus and in the lateral part of the internal layer of the median eminence forming a continuous cell mass presumably representing neuropeptide Y immunoreactive nerve cell bodies. The major arcuate dopamine/ tyrosine hydroxylase nerve cell group was found in the dorsomedial part. A large number of tyrosine hydroxylase immunoreactive nerve cell bodies in this region demonstrated punctate dopamine D1 receptor immunoreactivity but only a few presented dopamine D2 receptor immunoreactivity which were mainly found in a substantial number of tyrosine hydroxylase cell bodies of the ventral periventricular hypothalamic nucleus, also belonging to the tubero-infundibular dopamine neurons. Structural evidence for projections of the arcuate nerve cells into the median eminence was also obtained. Distal axons formed horizontal axons in the internal layer issuing a variable number of collaterals classified into single or multiple strands located in the external layer increasing our understanding of the dopamine nerve terminal networks in this region.  Dopamine D1 and D2 receptors may therefore directly and differentially modulate the activity and /or Dopamine synthesis of substantial numbers of tubero-infundibular dopamine neurons at the somatic and terminal level. The immunohistochemical work also gives support to the view that dopamine D1 receptors and/or dopamine D2 receptors in the lateral palisade zone by mediating dopamine volume transmission may contribute to the inhibition of luteinizing hormone releasing hormone release from nerve terminals in this region.

Multiple mantle upwellings through the transition zone beneath the Afar Depression?

NASA Astrophysics Data System (ADS)

Hammond, J. O.; Kendall, J. M.; Stuart, G. W.; Thompson, D. A.; Ebinger, C. J.; Keir, D.; Ayele, A.; Goitom, B.; Ogubazghi, G.

2012-12-01

Previous seismic studies using regional deployments of sensors in East-Africa show that low seismic velocities underlie Africa, but their resolution is limited to the top 200-300km of the Earth. Thus, the connection between the low velocities in the uppermost mantle and those imaged in global studies in the lower mantle is unclear. We have combined new data from Afar, Ethiopia with 7 other regional experiments and global network stations across Kenya, Ethiopia, Eritrea, Djibouti and Yemen, to produce high-resolution models of upper mantle P- and S-wave velocities to the base of the transition zone. Relative travel time tomographic inversions show that within the transition zone two focussed sharp-sided low velocity regions exist: one beneath the Western Ethiopian plateau outside the rift valley, and the other beneath the Afar depression. Estimates of transition zone thickness suggest that this is unlikely to be an artefact of mantle discontinuity topography as a transition zone of normal thickness underlies the majority of Afar and surrounding regions. However, a low velocity layer is evident directly above the 410 discontinuity, co-incident with some of the lowest seismic velocities suggesting that smearing of a strong low velocity layer of limited depth extent may contribute to the tomographic models in north-east Afar. The combination of seismic constraints suggests that small low temperature (<50K) upwellings may rise from a broader low velocity plume-like feature in the lower mantle. This interpretation is supported by numerical and analogue experiments that suggest the 660km phase change and viscosity jump may impede flow from the lower to upper mantle creating a thermal boundary layer at the base of the transition zone. This allows smaller, secondary upwellings to initiate and rise to the surface. These, combined with possible evidence of melt above the 410 discontinuity can explain the seismic velocity models. Our images of secondary upwellings suggest that there is no evidence for a plume in the classical sense (i.e. a narrow conduit). Instead, we propose that secondary upwellings rise from the base of the transition zone and connect with the northeast flowing African superswell in the upper mantle.

Structural control of the upper plate on the down-dip segmentation of subduction dynamics

NASA Astrophysics Data System (ADS)

Shi, Q.; Barbot, S.; Karato, S. I.; Shibazaki, B.; Matsuzawa, T.; Tapponnier, P.

2017-12-01

The geodetic and seismic discoveries of slow earthquakes in subduction zones have provided the observational evidence for the existence of the transition between megathrust earthquakes and the creeping behaviors. However, the mechanics behind slow earthquakes, and the period differential motion between the subducting slab and the overlying plate below the seismogenic zone, remain controversial. In Nankai subduction zone, the very-low-frequency earthquakes (VLFE), megathrust earthquakes, long-term slow earthquakes (duration of months or years) and the episodic tremor and slip zone (ETS) are located within the accretionary prism, the continental upper crust, the continental lower crust and the upmost mantle of the overriding plate, respectively. We use the rate-and-state friction law to simulate the periodic occurrence of VLFEs, megathrust earthquakes and the tremors in the ETS zone because of relatively high rock strength within these depth ranges. However, it is not feasible to use frictional instabilities to explain the long-term slow earthquakes in the lower crust where the ductile rock physics plays a significant role in the large-scale deformation. Here, our numerical simulations show that slow earthquakes at the depth of the lower crust may be the results of plastic instabilities in a finite volume of ductile material accompanying by the grain-size evolution. As the thickness of the fault zone increases with depth, deformation becomes distributed and the dynamic equilibrium of grain size, as a competition between thermally activated grain growth and damage-related grain size reduction, results in cycles of strain acceleration and strain deficit. In addition, we took into account the elevated pore pressure in the accretinary prism which is associated with small stress drop and low-frequency content of VLFEs and may contribute to the occurrence of tsunamigenic earthquakes. Hence, in our numerical simulations for the plate boundary system in Nankai, the down-sip segmentation of the subduction dynamic is attributed to the upper plate structure that vary with depth. The high pore pressure, grain-size evolution and alternation of the rock physics may explain the existence and the periodicity of different slow earthquakes from shallow to deep regions in the subduction zone.

Chemometric Study of Trace Elements in Hard Coals of the Upper Silesian Coal Basin, Poland

PubMed Central

Rompalski, Przemysław; Cybulski, Krzysztof; Chećko, Jarosław

2014-01-01

The objective of the study was the analysis of trace elements contents in coals of the Upper Silesian Coal Basin (USCB), which may pose a potential threat to the environment when emitted from coal processing systems. Productive carbon overburden in central and southern zones of the USCB is composed mostly of insulating tertiary formations of a thickness from a few m to 1,100 m, and is represented by Miocene and Pliocene formations. In the data study the geological conditions of the coal seams of particular zones of the USCB were taken into account and the hierarchical clustering analysis was applied, which enabled the exploration of the dissimilarities between coal samples of various zones of the USCB in terms of basic physical and chemical parameters and trace elements contents. Coals of the northern and eastern zones of the USCB are characterized by high average Hg and low average Ba, Cr, and Ni contents, whereas coals of southern and western zones are unique due to high average concentrations of Ba, Co, Cu, Ni, and V. Coals of the central part of the USCB are characterized by the highest average concentration of Mn and the lowest average concentrations of As, Cd, Pb, V, and Zn. PMID:24967424

Microtubule distribution in gravitropic protonemata of the moss Ceratodon

NASA Technical Reports Server (NTRS)

Schwuchow, J.; Sack, F. D.; Hartmann, E.

1990-01-01

Tip cells of dark-grown protonemata of the moss Ceratodon purpureus are negatively gravitropic (grow upward). They possess a unique longitudinal zonation: (1) a tip group of amylochloroplasts in the apical dome, (2) a plastid-free zone, (3) a zone of significant plastid sedimentation, and (4) a zone of mostly non-sedimenting plastids. Immunofluorescence of vertical cells showed microtubules distributed throughout the cytoplasm in a mostly axial orientation extending through all zones. Optical sectioning revealed a close spatial association between microtubules and plastids. A majority (two thirds) of protonemata gravistimulated for > 20 min had a higher density of microtubules near the lower flank compared to the upper flank in the plastid-free zone. This apparent enrichment of microtubules occurred just proximal to sedimented plastids and near the part of the tip that presumably elongates more to produce curvature. Fewer than 5% of gravistimulated protonemata had an enrichment in microtubules near the upper flank, whereas 14% of vertical protonemata were enriched near one of the side walls. Oryzalin and amiprophos-methyl (APM) disrupted microtubules, gravitropism, and normal tip growth and zonation, but did not prevent plastid sedimentation. We hypothesize that a microtubule redistribution plays a role in gravitropism in this protonema. This appears to be the first report of an effect of gravity on microtubule distribution in plants.

Slab temperature controls on the Tonga double seismic zone and slab mantle dehydration

PubMed Central

Wei, S. Shawn; Wiens, Douglas A.; van Keken, Peter E.; Cai, Chen

2017-01-01

Double seismic zones are two-layered distributions of intermediate-depth earthquakes that provide insight into the thermomechanical state of subducting slabs. We present new precise hypocenters of intermediate-depth earthquakes in the Tonga subduction zone obtained using data from local island–based, ocean-bottom, and global seismographs. The results show a downdip compressional upper plane and a downdip tensional lower plane with a separation of about 30 km. The double seismic zone in Tonga extends to a depth of about 300 km, deeper than in any other subduction system. This is due to the lower slab temperatures resulting from faster subduction, as indicated by a global trend toward deeper double seismic zones in colder slabs. In addition, a line of high seismicity in the upper plane is observed at a depth of 160 to 280 km, which shallows southward as the convergence rate decreases. Thermal modeling shows that the earthquakes in this “seismic belt” occur at various pressures but at a nearly constant temperature, highlighting the important role of temperature in triggering intermediate-depth earthquakes. This seismic belt may correspond to regions where the subducting mantle first reaches a temperature of ~500°C, implying that metamorphic dehydration of mantle minerals in the slab provides water to enhance faulting. PMID:28097220

Sedimentation across the central California oxygen minimum zone: an alternative coastal upwelling sequence.

USGS Publications Warehouse

Vercoutere, T.L.; Mullins, H.T.; McDougall, K.; Thompson, J.B.

1987-01-01

Distribution, abundance, and diversity of terrigenous, authigenous, and biogenous material provide evidence of the effect of bottom currents and oxygen minimum zone (OMZ) on continental slope sedimentation offshore central California. Three major OMZ facies are identified, along the upper and lower edges of OMZ and one at its core.-from Authors

[Effect of GABA, sodium glutamate and glycine on evoked potentials in the dental zones of the cerebral cortex].

PubMed

Degtiarev, V P

1979-01-01

Intraventricular administration of gamma-aminobutyric acid (GABA) and glycine decreased, whereas sodium glutamate increased the amplitude of primary responses of dental zones of the somatosensory cortex, which arose during electric stimulation of the pulp of the rabbit upper incisors. No changes in the latent periods were recorded.

Implant therapy in the esthetic zone: smile line assessment.

PubMed

Kourkouta, Stella

2011-04-01

Assessment of the smile or lip line is imperative when implant therapy is carried out in the esthetic zone. The smile is generally defined as high, average, or low. Females are reported to have higher lip lines than males, which means that they are at greater risk when placing and restoring implants in the esthetic zone. Maximum upper lip elevation, usually observed during a strained posed smile, should be assessed. This paper discusses some clinical observations and concepts in relation to smile line assessment for implant therapy in the esthetic zone. (Int J Periodontics Restorative Dent 2011;31:195-201.).

Geologic Map of the Kings Mountain and Grover Quadrangles, Cleveland and Gaston Counties, North Carolina, and Cherokee and York Counties, South Carolina

USGS Publications Warehouse

Horton, J. Wright

2008-01-01

This geologic map of the Kings Mountain and Grover 7.5-min quadrangles, N.C.-S.C., straddles a regional geological boundary between the Inner Piedmont and Carolina terranes. The Kings Mountain sequence (informal name) on the western flank of the Carolina terrane in this area includes the Neoproterozoic Battleground and Blacksburg Formations. The Battleground Formation has a lower part consisting of metavolcanic rocks and interlayered schist and an upper part consisting of quartz-sericite phyllite and schist interlayered with quartz-pebble metaconglomerate, aluminous quartzite, micaceous quartzite, manganiferous rock, and metavolcanic rocks. The Blacks-burg Formation consists of phyllitic metasiltstone interlayered with thinner units of marble, laminated micaceous quartzite, hornblende gneiss, and amphibolite. Layered metamorphic rocks of the Inner Piedmont terrane include muscovite-biotite gneiss, muscovite schist, and amphibolite. The Kings Mountain sequence has been intruded by metatonalite and metatrondhjemite (Neoproterozoic), metagabbro and metadiorite (Paleozoic?), and the High Shoals Granite (Pennsylvanian). Layered metamorphic rocks of the Inner Piedmont in this area have been intruded by the Toluca Granite (Ordovician?), the Cherryville Granite and associated pegmatite (Mississippian), and spodumene pegmatite (Mississippian). Diabase dikes (early Jurassic) are locally present throughout the area. Ductile fault zones of regional scale include the Kings Mountain and Kings Creek shear zones. In this area, the Kings Mountain shear zone forms the boundary between the Inner Piedmont and Carolina terranes, and the Kings Creek shear zone separates the Battleground Formation from the Blacksburg Formation. Structural styles change across the Kings Mountain shear zone from steeply dipping layers, foliations, and folds on the southeast to gently and moderately dipping layers, foliations, and recumbent folds on the northwest. Mineral assemblages in the Kings Mountain sequence show a westward decrease from upper amphibolite facies (sillimanite zone) near the High Shoals Granite in the eastern side of the map area to upper greenschist (epidote-amphibolite) facies in the south-central part of the area near the Kings Mountain shear zone. Amphibolite-facies mineral assemblages in the Inner Piedmont terrane increase in grade from the kyanite zone near the Kings Mountain shear zone to the sillimanite zone in the northwestern part of the map area. Surficial deposits include alluvium in the stream valleys and colluvium along ridges and steep slopes. These quadrangles are unusual in the richness and variety of the mineral deposits that they contain, which include spodumene (lithium), cassiterite (tin), mica, feldspar, silica, clay, marble, kyanite and sillimanite, barite, manganese, sand and gravel, gold, pyrite, and iron.

Saudi Arabian seismic-refraction profile: A traveltime interpretation of crustal and upper mantle structure

USGS Publications Warehouse

Mooney, W.D.; Gettings, M.E.; Blank, H.R.; Healy, J.H.

1985-01-01

The crustal and upper mantle compressional-wave velocity structure across the southwestern Arabian Shield has been investigated by a 1000-km-long seismic refraction profile. The profile begins in Mesozoic cover rocks near Riyadh on the Arabian Platform, trends southwesterly across three major Precambrian tectonic provinces, traverses Cenozoic rocks of the coastal plain near Jizan, and terminates at the outer edge of the Farasan Bank in the southern Red Sea. More than 500 surveyed recording sites were occupied, and six shot points were used, including one in the Red Sea. Two-dimensional ray-tracing techniques, used to analyze amplitude-normalized record sections indicate that the Arabian Shield is composed, to first order, of two layers, each about 20 km thick, with average velocities of about 6.3 km/s and 7.0 km/s, respectively. West of the Shield-Red Sea margin, the crust thins to a total thickness of less than 20 km, beyond which the Red Sea shelf and coastal plain are interpreted to be underlain by oceanic crust. A major crustal inhomogeneity at the northeast end of the profile probably represents the suture zone between two crustal blocks of different composition. Elsewhere along the profile, several high-velocity anomalies in the upper crust correlate with mapped gneiss domes, the most prominent of which is the Khamis Mushayt gneiss. Based on their velocities, these domes may constitute areas where lower crustal rocks have been raised some 20 km. Two intracrustal reflectors in the center of the Shield at 13 km depth probably represent the tops of mafic intrusives. The Mohorovic??ic?? discontinuity beneath the Shield varies from a depth of 43 km and mantle velocity of 8.2 km/s in the northeast to a depth of 38 km and mantle velocity of 8.0 km/s depth in the southwest near the Shield-Red Sea transition. Two velocity discontinuities occur in the upper mantle, at 59 and 70 km depth. The crustal and upper mantle velocity structure of the Arabian Shield is interpreted as revealing a complex crust derived from the suturing of island arcs in the Precarnbrian. The Shield is currently flanked by the active spreading boundary in the Red Sea. ?? 1985.

Photosynthetic characteristics and mycosporine-like amino acids under UV radiation: a competitive advantage of Mastocarpus stellatus over Chondrus crispus at the Helgoland shoreline?

NASA Astrophysics Data System (ADS)

Bischof, K.; Kräbs, G.; Hanelt, D.; Wiencke, C.

2000-05-01

Chondrus crispus and Mastocarpus stellatus both inhabit the intertidal and upper sublittoral zone of Helgoland, but with C. crispus generally taking a lower position. Measurements of chlorophyll fluorescence, activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), and content and composition of UV absorbing mycosporine-like amino acids (MAAs) were conducted in the laboratory, to test whether susceptibility to UV radiation may play a role in the vertical distribution of these two species. Effective and maximal quantum yield of photochemistry as well as maximal electron transport rate (ETRmax) in C. crispus were more strongly affected by UV-B radiation than in M. stellatus. In both species, no negative effects of the respective radiation conditions were found on total activity of RubisCO. Total MAA content in M. stellatus was up to 6-fold higher than in C. crispus and the composition of MAAs in the two species was different. The results indicate that, among others, UV-B sensitivity may be a factor restricting C. crispus to the lower intertidal and upper sublittoral zone, whereas M. stellatus is better adapted to UV radiation and is therefore more competitive in the upper intertidal zone.

Quality of economically extractable coal beds in the Gillette coal field as compared with other Tertiary coal beds in the Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Ellis, Margaret S.

2002-01-01

The Powder River Basin, and specifically the Gillette coal field, contains large quantities of economically extractable coal resources. These coal resources have low total sulfur content and ash yield, and most of the resources are subbituminous in rank. A recent U.S Geological Survey study of economically extractable coal in the Gillette coal field focused on five coal beds, the Wyodak rider, Upper Wyodak, Canyon, Lower Wyodak-Werner, and Gates/Kennedy. This report compares the coal quality of these economically extractable coal beds to coal in the Wyodak-Anderson coal zone in the Powder River Basin and in the Gillette coal field (Flores and others, 1999) and other produced coal in the Gillette coal field (Glass, 2000). The Upper Wyodak, Canyon, and Lower Wyodak/Werner beds are within the Wyodak-Anderson coal zone. Compared with all coal in the Wyodak-Anderson coal zone, both throughout the Powder River Basin and just within the Gillette coal field; the thick, persistent Upper Wyodak coal bed in the Gillette coal field has higher mean gross calorific value (8,569 Btu/lb), lower mean ash yield (5.8 percent), and lower mean total sulfur content (0.46 percent).

Novel human mutation and CRISPR/Cas genome-edited mice reveal the importance of C-terminal domain of MSX1 in tooth and palate development

PubMed Central

Mitsui, Silvia Naomi; Yasue, Akihiro; Masuda, Kiyoshi; Naruto, Takuya; Minegishi, Yoshiyuki; Oyadomari, Seiichi; Noji, Sumihare; Imoto, Issei; Tanaka, Eiji

2016-01-01

Several mutations, located mainly in the MSX1 homeodomain, have been identified in non-syndromic tooth agenesis predominantly affecting premolars and third molars. We identified a novel frameshift mutation of the highly conserved C-terminal domain of MSX1, known as Msx homology domain 6 (MH6), in a Japanese family with non-syndromic tooth agenesis. To investigate the importance of MH6 in tooth development, Msx1 was targeted in mice with CRISPR/Cas system. Although heterozygous MH6 disruption did not alter craniofacial development, homozygous mice exhibited agenesis of lower incisors with or without cleft palate at E16.5. In addition, agenesis of the upper third molars and the lower second and third molars were observed in 4-week-old mutant mice. Although the upper second molars were present, they were abnormally small. These results suggest that the C-terminal domain of MSX1 is important for tooth and palate development, and demonstrate that that CRISPR/Cas system can be used as a tool to assess causality of human disorders in vivo and to study the importance of conserved domains in genes. PMID:27917906

Novel human mutation and CRISPR/Cas genome-edited mice reveal the importance of C-terminal domain of MSX1 in tooth and palate development.

PubMed

Mitsui, Silvia Naomi; Yasue, Akihiro; Masuda, Kiyoshi; Naruto, Takuya; Minegishi, Yoshiyuki; Oyadomari, Seiichi; Noji, Sumihare; Imoto, Issei; Tanaka, Eiji

2016-12-05

Several mutations, located mainly in the MSX1 homeodomain, have been identified in non-syndromic tooth agenesis predominantly affecting premolars and third molars. We identified a novel frameshift mutation of the highly conserved C-terminal domain of MSX1, known as Msx homology domain 6 (MH6), in a Japanese family with non-syndromic tooth agenesis. To investigate the importance of MH6 in tooth development, Msx1 was targeted in mice with CRISPR/Cas system. Although heterozygous MH6 disruption did not alter craniofacial development, homozygous mice exhibited agenesis of lower incisors with or without cleft palate at E16.5. In addition, agenesis of the upper third molars and the lower second and third molars were observed in 4-week-old mutant mice. Although the upper second molars were present, they were abnormally small. These results suggest that the C-terminal domain of MSX1 is important for tooth and palate development, and demonstrate that that CRISPR/Cas system can be used as a tool to assess causality of human disorders in vivo and to study the importance of conserved domains in genes.

Element mobility studies of two drill-cores from the Götemar Granite (Kråkemåla test site), southeast Sweden

USGS Publications Warehouse

Smellie, John A.T.; Stuckless, John S.

1985-01-01

The pervasive alteration and the more recent mobilisation of U are evident to a depth of at least 600 m. The effects are most prevalent along major fracture zones and within the upper 250–300 m of one drill-hole where a high frequency of crush zones has been noted. Higher Fe oxidation ratios, higher Rb contents, lower U contents and correspondingly higher Th/U ratios, all characterise this zone.

Environmental Assessment: For Joint Biological Point Detection System (JBPDS) at Multiple Test Ranges, Eglin Air Force Base, Florida

DTIC Science & Technology

2003-06-01

bed. This clay layer restricts the downward migration of pollutants and restricts saline water from Choctawhatchee Bay and the Gulf of Mexico from...Because it is saline , the Lower Limestone unit is not used as a water source (U.S. Air Force, 1995). Groundwater storage and movement in the Upper... purslane , among others. Inland from the produne zone is the “scrub” zone. Vegetation found in this zone is usually stunted and wind/salt sprayed

A Detailed 3D Seismic Velocity Structure of the Subducting Pacific Slab Beneath Hokkaido, Tohoku and Kanto, Japan, by Double-Difference Tomography

NASA Astrophysics Data System (ADS)

Tsuji, Y.; Nakajima, J.; Kita, S.; Okada, T.; Matsuzawa, T.; Hasegawa, A.

2007-12-01

Three-dimensional heterogeneous structure beneath northeastern (NE) Japan has been investigated by previous studies and an inclined seismic low-velocity zone is imaged in the mantle wedge sub-parallel to the down-dip direction of the subducting slab (Zhao et al., 1992, Nakajima et al., 2001). However, the heterogeneous structure within the slab has not been well studied even though it is very important to understand the whole process of water transportation from the slab to the surface. Here we show a detailed 3D seismic velocity structure within the subducted Pacific slab around Japan and propose a water-transportation path from the slab to the mantle wedge. In this study, we estimated 3D velocity structure within the Pacific slab by the double-difference tomography (Zhang and Thurber, 2003). We divided the study area, from Hokkaido to Kanto, into 6 areas due to the limitation of memory and computation time. In each area, arrival-time data of 7,500-17,000 events recorded at 70-170 stations were used in the analysis. The total number of absolute travel-time data was about 140,000-312,000 for P wave and 123,000-268,000 for S wave, and differential data were about 736,000-1,920,000 for P wave and 644,000-1,488,000 for S wave. Horizontal and vertical grid separations are 10-25 km and 6.5 km, respectively. RMS residuals of travel times for P wave decreased from 0.23s to 0.09s and for S wave from 0.35s to 0.13s. The obtained results are as follows: (1) a remarkable low-Vs zone exists in the uppermost part of the subducting slab, (2) it extends down to a depth of about 80 km, (3) the termination of this low-Vs zone almost corresponds to the "seismic belt" recently detected in the upper plane of the double seismic zone (Kita et al.,2006; Hasegawa et al., 2007), (4) at depths deeper than 80 km, a low-Vs and high-Vp/Vs zone is apparently distributed in the mantle wedge, immediately above the slab crust. We consider that these features reflect water-transportation processes from the slab to the mantle wedge. A low- Vs zone in the uppermost part of the subducting slab corresponds to the hydrous oceanic crust since its absolute velocity is about 4.0 km/s, comparable to that expected for the oceanic crust (Hacker et al., 2003). Dehydration reactions occur in the oceanic crust as temperature and pressure increase, and a relatively large amount of water is released at depths of about 80-100 km. The water generated by dehydration reactions could migrate upward and react peridotite at the base of the mantle wedge, forming a thin-serpentine layer there. Then, the layer is dragged by the subducting slab to deeper depths (e.g. Iwamori, 1998). Such water-transportation processes from the slab to the mantle wedge are partly constrained by a recent receiver function analysis (Kawakatsu and Watada, 2007). We further found an along-arc variation of the termination depth of the low-velocity oceanic crust, suggesting the along-arc variation in the amount of fluids released from the slab.

Sheet intrusions and deformation of Piton des Neiges, and their implication for the volcano-tectonics of La Réunion

NASA Astrophysics Data System (ADS)

Chaput, Marie; Famin, Vincent; Michon, Laurent

2017-10-01

To understand the volcano-tectonic history of Piton des Neiges (the dormant volcano of La Réunion), we measured in the field the orientation of sheeted intrusions and deformation structures, and interpreted the two datasets separately with a paleostress inversion. Results show that the multiple proposed rift zones may be simplified into three trends: (1) a N30°E, 5 km wide linear rift zone running to the south of the edifice, active in the shield building (≥ 2.48-0.43 Ma) and terminal stages (190-22 ka); (2) a curved N110 to N160°E rift zone, widening from 5 km to 10 km toward the NW flank, essentially active during the early emerged shield building (≥ 1.3 Ma); and (3) two sill zones, ≤ 1 km thick in total, in the most internal parts of the volcano, active in the shield building and terminal stages. In parallel, deformation structures reveal that the tectonics of the edifice consisted in three end-member stress regimes sharing common stress axes: (1) NW-SE extension affecting in priority the south of the edifice near the N30°E rift zone; (2) NNE-SSW extension on the northern half of the volcano near the N110-160°E rift zone; (3) compression occurring near the sill zones, with a NE-SW or NW-SE maximum principal stress. These three stress regimes are spatially correlated and mechanically compatible with the injection trends. Combined together, our data show that the emerged Piton des Neiges underwent sector spreading delimited by perpendicular rift zones, as observed on Piton de la Fournaise (the active volcano of La Réunion). Analogue experiments attribute such sector spreading to brittle edifices built on a weaker substratum. We therefore conclude that La Réunion volcanoes are both brittle, as opposed to Hawaiian volcanoes or Mount Etna whose radial spreading is usually attributed to a ductile body within the edifices.

Environmental Assessment for Terminal Area Improvements, Charleston International Airport

DTIC Science & Technology

2011-11-17

Resources and/or USFWS . 7. An erosion and sedimentation control plan that includes the use of construction controls to prevent degradation of water...CCAA property and surrounding lands were historically used for phosphate fertilizer mining. Prior to the development of this property as an airport...number of zoning classifications which control land use within the city limits. The Airport is in an area zoned as "Light Industrial District" a

The Wallula fault and tectonic framework of south-central Washington, as interpreted from magnetic and gravity anomalies

USGS Publications Warehouse

Blakely, Richard J.; Sherrod, Brian; Weaver, Craig S.; Wells, Ray; Rohay, Alan C.

2014-01-01

The Yakima fold and thrust belt (YFTB) in central Washington has accommodated regional, mostly north-directed, deformation of the Cascadia backarc since prior to emplacement of Miocene flood basalt of the Columbia River Basalt Group (CRBG). The YFTB consists of two structural domains. Northern folds of the YFTB strike eastward and terminate at the western margin of a 20-mGal negative gravity anomaly, the Pasco gravity low, straddling the North American continental margin. Southern folds of the YFTB strike southeastward, form part of the Olympic–Wallowa lineament (OWL), and pass south of the Pasco gravity low as the Wallula fault zone. An upper crustal model based on gravity and magnetic anomalies suggests that the Pasco gravity low is caused in part by an 8-km-deep Tertiary basin, the Pasco sub-basin, abutting the continental margin and concealed beneath CRBG. The Pasco sub-basin is crossed by north-northwest-striking magnetic anomalies caused by dikes of the 8.5 Ma Ice Harbor Member of the CRBG. At their northern end, dikes connect with the eastern terminus of the Saddle Mountains thrust of the YFTB. At their southern end, dikes are disrupted by the Wallula fault zone. The episode of NE–SW extension that promoted Ice Harbor dike injection apparently involved strike-slip displacement on the Saddle Mountains and Wallula faults. The amount of lateral shear on the OWL impacts the level of seismic hazard in the Cascadia region. Ice Harbor dikes, as mapped with aeromagnetic data, are dextrally offset by the Wallula fault zone a total of 6.9 km. Assuming that dike offsets are tectonic in origin, the Wallula fault zone has experienced an average dextral shear of 0.8 mm/y since dike emplacement 8.5 Ma, consistent with right-lateral stream offsets observed at other locations along the OWL. Southeastward, the Wallula fault transfers strain to the north-striking Hite fault, the possible location of the M 5.7 Milton-Freewater earthquake in 1936.

Simulation of saltwater movement in the Floridan aquifer system, Hilton Head Island, South Carolina

USGS Publications Warehouse

Bush, Peter W.

1988-01-01

Freshwater to supply Hilton Head Island, S.C., is obtained from the upper permeable zone of the Upper Floridan aquifer. Long-term pumping at Savannah, Ga., and the steadily increasing pumping on Hilton Head Island, have lowered Upper Floridan heads near the center of the island from about 10 feet above sea level to about 6 to 7 feet below sea level. The seaward hydraulic gradient that existed before pumping began has been reversed, thus increasing the potential for saltwater intrusion. Simulations of predevelopment, recent, and future ground-water flow in the Floridan aquifer system beneath the north end of Hilton Head Island and Port Royal Sound are presented. A finite-element model for fluid-density-dependent ground-water flow and solute transport was used in cross section. The general configuration of the simulated predevelopment flowfield is typical of a coastal aquifer having a seaward gradient in the freshwater. The freshwater flows toward Port Royal Sound over an intruding wedge of saltwater. The simulated flowfield at the end of 1983 shows that ground water in the Floridan aquifer system beneath most of Hilton Head Island has reversed its predevelopment direction and is moving toward Savannah. The distribution of chloride concentrations, based on simulation at the end of 1983, is about the same as the predevelopment distribution of chloride concentrations obtained from simulation. Results of two 50-year simulations from 1983 to 2034 suggest that there will be no significant threat of saltwater intrusion into the upper permeable zone of the Upper Floridan aquifer if heads on Hilton Head Island remain at current levels for the next 45 to 50 years. However, if head decline continues at the historical rate, any flow that presently occurs from the north end of the island toward Port Royal Sound will cease, allowing lateral intrusion of saltwater to proceed. Even under these conditions, chloride concentrations in the upper permeable zone of the Upper Floridan aquifer beneath Hilton Head Island should remain below 250 milligrams per liter for the next 45 to 50 years. Aquifer properties and selected boundary conditions were tested with several 1,000-year simulations which show that lateral permeability, transverse dispersivity, and landward boundary flow have the most influence on saltwater movement in the Upper Floridan aquifer.

Seismic Velocity Gradients Across the Transition Zone

NASA Astrophysics Data System (ADS)

Escalante, C.; Cammarano, F.; de Koker, N.; Piazzoni, A.; Wang, Y.; Marone, F.; Dalton, C.; Romanowicz, B.

2006-12-01

One-D elastic velocity models derived from mineral physics do a notoriously poor job at predicting the velocity gradients in the upper mantle transition zone, as well as some other features of models derived from seismological data. During the 2006 CIDER summer program, we computed Vs and Vp velocity profiles in the upper mantle based on three different mineral physics approaches: two approaches based on the minimization of Gibbs Free Energy (Stixrude and Lithgow-Bertelloni, 2005; Piazzoni et al., 2006) and one obtained by using experimentally determined phase diagrams (Weidner and Wang, 1998). The profiles were compared by assuming a vertical temperature profile and two end-member compositional models, the pyrolite model of Ringwood (1979) and the piclogite model of Anderson and Bass (1984). The predicted seismic profiles, which are significantly different from each other, primarily due to different choices of properties of single minerals and their extrapolation with temperature, are tested against a global dataset of P and S travel times and spheroidal and toroidal normal mode eigenfrequencies. All the models derived using a potential temperature of 1600K predict seismic velocities that are too slow in the upper mantle, suggesting the need to use a colder geotherm. The velocity gradient in the transition zone is somewhat better for piclogite than for pyrolite, possibly indicating the need to increase Ca content. The presence of stagnant slabs in the transition zone is a possible explanation for the need for 1) colder temperature and 2) increased Ca content. Future improvements in seismic profiles obtained from mineral physics will arise from better knowledge of elastic properties of upper mantle constituents and aggregates at high temperature and pressure, a better understanding of differences between thermodynamic models, and possibly the effect of water through and on Q. High resolution seismic constraints on velocity jumps at 400 and 660 km also need to be included. earth.org/2006/workshop.html

Upper Neoproterozoic-Lower Cambrian sedimentary successions in the Central Iberian Zone (Spain): sequence stratigraphy, petrology and chemostratigraphy. Implications for other European zones

NASA Astrophysics Data System (ADS)

Valladares, M. I.; Barba, P.; Ugidos, J. M.; Colmenero, J. R.; Armenteros, I.

The Upper Neoproterozoic-Lower Cambrian sedimentary succession in the central areas of the Central Iberian Zone has been subdivided into 12 mostly siliciclastic lithostratigraphic units, ranging in thickness between 1800 and 3900m. The lithology and facies of each unit are described and the facies associations are interpreted. The facies resulted mainly from turbidity currents and debris flows and, to a lesser extent, from submarine slides and traction flows. The facies associations suggest that sedimentation took place in slope and base-of-slope environments. Two depositional sequences are recognized, separated by a type-1 unconformity. The lower sequence is of Late Neoproterozoic age (units I-IV) and exhibits lowstand, transgressive, and highstand systems tracts. Most of the upper sequence is probably of Early Cambrian age (units V-XII). It begins at the base of unit V and possibly ends with the Tamames Limestone Formation. The upper sequence records a lowstand systems tract and minor-order sea-level oscillations. In the Cambrian units there are higher amounts of feldspar and smaller quantities of intrabasinal clasts than in the Neoproterozoic units. The modal data plot close to the Q-L and Qm-Lt sides of Q-F-L and Qm-F-Lt triangular diagrams, suggesting a provenance from a recycled orogen evolving into a provenance from a craton interior towards the top of the succession. The chemical results, based mainly on Al2O3, TiO2, Zr, and Nb abundances in shales from all the units, strongly suggest a gradual compositional change within this sedimentary succession. Together with the petrological data, the chemical results do not reveal any obvious coeval volcanic contribution to the sediments. On the basis of the chemical data, a comparison is made with other European zones containing detrital sediments composed of reworked crustal components.

Geometry and segmentation of the North Anatolian Fault beneath the Marmara Sea, Turkey, deduced from long-term ocean bottom seismographic observations

NASA Astrophysics Data System (ADS)

Yamamoto, Yojiro; Takahashi, Narumi; Pinar, Ali; Kalafat, Dogan; Citak, Seckin; Comoglu, Mustafa; Polat, Remzi; Kaneda, Yoshiyuki

2017-04-01

Both the geometry and the depth of the seismogenic zone of the North Anatolian Fault under the Marmara Sea (the Main Marmara Fault; MMF) are poorly understood, in part because of the fault's undersea location. We have started a series of long-term ocean bottom seismographs (OBSs) observation since 2014, as a part of the SATREPS collaborative project between Japan and Turkey namely "Earthquake and Tsunami Disaster Mitigation in the Marmara Region and Disaster Education in Turkey". We recorded 10 months of microseismic data with a dense array of OBSs from Sep. 2014 to Jul. 2015 and then applied double-difference relocation and 3-D tomographic modeling to obtain precise hypocenters on the MMF beneath the central and western Marmara Sea. The hypocenters show distinct lateral changes along the MMF: (1) Both the upper and lower crust beneath the Western High are seismically active and the maximum focal depth reaches 26 km, (2) seismic events are confined to the upper crust beneath the region extending from the eastern part of the Central Basin to the Kumburgaz Basin, and (3) the magnitude and direction of dip of the main fault changes under the Central Basin, where there is also an abrupt change in the depth of the lower limit of the seismogenic zone. We attribute this change to a segment boundary of the MMF. Our data show that the upper limit of the seismogenic zone corresponds to sedimentary basement. We also identified several inactive seismicity regions within the upper crust along the MMF; their spatial extent beneath the Kumburgaz Basin is greater than beneath the Western High. From the comparison with seafloor extensometer data, we consider that these inactive seismicity regions might indicate zones of strong coupling that are accumulating stress for release during future large earthquakes. In this presentation, we will also show the preliminary result of our second phase observation from Jul. 2015 to Jun. 2016.

Fusion competent synaptic vesicles persist upon active zone disruption and loss of vesicle docking

PubMed Central

Wang, Shan Shan H.; Held, Richard G.; Wong, Man Yan; Liu, Changliang; Karakhanyan, Aziz; Kaeser, Pascal S.

2016-01-01

In a nerve terminal, synaptic vesicle docking and release are restricted to an active zone. The active zone is a protein scaffold that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Here, we generated conditional knockout mice removing the active zone proteins RIM and ELKS, which additionally led to loss of Munc13, Bassoon, Piccolo, and RIM-BP, indicating disassembly of the active zone. We observed a near complete lack of synaptic vesicle docking and a strong reduction in vesicular release probability and the speed of exocytosis, but total vesicle numbers, SNARE protein levels, and postsynaptic densities remained unaffected. Despite loss of the priming proteins Munc13 and RIM and of docked vesicles, a pool of releasable vesicles remained. Thus, the active zone is necessary for synaptic vesicle docking and to enhance release probability, but releasable vesicles can be localized distant from the presynaptic plasma membrane. PMID:27537483

Freight Terminals Operating Environment

DOT National Transportation Integrated Search

1981-06-01

The research analysis has been directed toward (1) developing a realistic, quantitative description of the structure of the economic zones that are centered upon medium-size urban areas, (2) determining the nature of traffic in manufactured goods whi...