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2005

GeoQUEST

Articles 1 - 16 of 16

Full-Text Articles in Physical Sciences and Mathematics

Measurements Of Trace Gas Emissions From Australian Forest Fires And Correlations With Coincident Measurements Of Aerosol Optical Depth, Clare Paton-Walsh, N. B. Jones, Stephen R. Wilson, V Haverd, A. Meier, D. W. Griffith Dec 2005

Measurements Of Trace Gas Emissions From Australian Forest Fires And Correlations With Coincident Measurements Of Aerosol Optical Depth, Clare Paton-Walsh, N. B. Jones, Stephen R. Wilson, V Haverd, A. Meier, D. W. Griffith

Faculty of Science - Papers (Archive)

We present vertically integrated measurements of C2H2, C2H4, C2H6, HCOOH, CO, H2CO, HCN and NH3 through smoke plumes from Australian forest fires measured by ground-based solar absorption spectroscopy. The column amounts of these gases are highly correlated with simultaneous, co-located measurements of aerosol optical depth, providing a potential method of mapping biomass-burning emissions using satellite measurements of aerosol optical depth. We have calculated emission ratios relative to CO for the trace gases using aerosol optical depth as a proxy for CO and converted to emission factors by using an average emission factor for CO from literature measurements of extra-tropical forest …


Radiocarbon In Corals From The Cocos (Keeling) Islands And Implications For Indian Ocean Circulation, Q Hua, Colin D. Woodroffe, Scott Smithers, M Barbetti, David Fink Jan 2005

Radiocarbon In Corals From The Cocos (Keeling) Islands And Implications For Indian Ocean Circulation, Q Hua, Colin D. Woodroffe, Scott Smithers, M Barbetti, David Fink

Faculty of Science - Papers (Archive)

Annual bands of a Porites coral from the Cocos (Keeling) Islands, eastern Indian Ocean, were analysed by radiocarbon for 1955–1985 AD. A rapid oceanic response of the site to bomb 14C is found, with a maximum D14C value of 132% in 1975. This value is considerably higher than those for the northwestern Indian Ocean, suggesting that surface waters reaching Cocos are not derived from the Arabian Sea. Instead, D14C values for Cocos and those for Watamu (Kenya) agree well over most of the study interval, suggesting that the South Equatorial Current carries 14C-elevated water rather than 14C-depleted water westward across …


Seasonal Variations Of Co And Hcn In The Troposphere Measured By Solar Absorption Spectroscopy Over Poker Flat, Alaska, Y Kasai, A. Kagawa, Nicholas B. Jones, A. Fujiwara, K. Seki, Y. Murayama, F Murcray Jan 2005

Seasonal Variations Of Co And Hcn In The Troposphere Measured By Solar Absorption Spectroscopy Over Poker Flat, Alaska, Y Kasai, A. Kagawa, Nicholas B. Jones, A. Fujiwara, K. Seki, Y. Murayama, F Murcray

Faculty of Science - Papers (Archive)

Tropospheric partial column abundances of CO and HCN have been retrieved from infrared solar spectra observed with a ground-based spectrometer at Poker Flat Alaska (65°N, 147°W) over the time period from 2000 to 2004. From these data we report the transpacific transport induced inter-annual variability of tropospheric CO over Poker Flat. This is the first report of solar infrared data from the Poker Flat station, where the geographical location of the site means that remote sensing measurements are sampling the transport of transpacific air parcels going to Northern America from Eastern Siberia and Asia. The five year time-span of the …


Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson Jan 2005

Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson

Faculty of Science - Papers (Archive)

A prominent characteristic of streams draining catchments in West Dapto, New South Wales, are well developed macrochannels that have formed within alluvial terraces in mid-catchment zones. A detailed hydraulic modelling study using HEC-RAS, HEC-GeoRAS and Arcview GIS indicates that these macrochannels are scaled to accommodate high magnitude floods. They offer a significant degree of natural protection from flood events up to and in excess of 100 years recurrence interval, essentially by operating as 'bankfull' channels during such events. Macrochannel landforms can be clearly distinguished and mapped on fine-scale digital elevation models (DEMs) and other GIS data sources such as rectified …


Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, T Blumenstock, M Buchwitz, R De Beek, Nicholas B. Jones, David W. Griffith, P Demoulin, A G Frankenberg, H Duchatelet, Hans Fast Jan 2005

Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, T Blumenstock, M Buchwitz, R De Beek, Nicholas B. Jones, David W. Griffith, P Demoulin, A G Frankenberg, H Duchatelet, Hans Fast

Faculty of Science - Papers (Archive)

Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered 5 here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.4, 0.41 for CH4), IMAP-DOAS (version 0.9) and IMLM (version 5.5) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences that satisfy the temporal and spatial collocation criteria, the 10 SCIAMACHY …


Different Fouling Modes Of Submerged Hollow-Fiber And Flat-Sheet Membranes Induced By High Strength Wastewater With Concurrent Biofouling, Faisal I. Hai, Kazuo Yamamoto, Kensuke Fukushi Jan 2005

Different Fouling Modes Of Submerged Hollow-Fiber And Flat-Sheet Membranes Induced By High Strength Wastewater With Concurrent Biofouling, Faisal I. Hai, Kazuo Yamamoto, Kensuke Fukushi

Faculty of Science - Papers (Archive)

Exploration of two major commercialized flat-sheet and hollow-fiber membranes in a submerged membrane fungi reactor fed with a synthetic textile wastewater revealed striking differences in the extent and mechanism of fouling between the two types, indicating a case-specific scope of choice between the two for industrial wastewater treatment. The hollow-fiber membrane exhibited fouling with a cake layer composed of fungi and starch, intensity being proportional to the operating flux (0.05–0.3 m/d). Conversely, the flat-sheet membrane suffered from immediate internal pore blocking beyond a critical flux of 0.2 m/d. During the experiment with major constituents of the synthetic wastewater separately, while …


A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali Jan 2005

A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali

Faculty of Science - Papers (Archive)

This study has analyzed the generation and characteristics of solid waste in Dhaka city, along with the associated environmental impacts and existing solid waste management practices. Special focus was given on the effect of composting on final disposal of solid waste and effect of landfill site location on transportation cost. An estimate of the future generation rate indicates that the present generation rate of 3500 tons/day may exceed 30 thousand tons/day by the year 2020.The mixed waste dumped at dumping sites is characterized with high organic content and high moisture content (about 80% and 50-70% by weight, respectively). According to …


New Pieces To The Archaean Terrane Jigsaw Puzzle In The Nuuk Region, Southern West Greeland: Steps In Transforming A Simple Insight Into A Complex Regional Tectonothermal Model, Clark R L Friend, Allen Phillip Nutman Jan 2005

New Pieces To The Archaean Terrane Jigsaw Puzzle In The Nuuk Region, Southern West Greeland: Steps In Transforming A Simple Insight Into A Complex Regional Tectonothermal Model, Clark R L Friend, Allen Phillip Nutman

Faculty of Science - Papers (Archive)

In the south of the Nuuk region of West Greenland our 1980s mapping recognized four Archaean gneiss terranes (Færingehavn, Tre Brødre, Tasiusarsuaq and Akia terranes) with different protolith ages and separate early tectonothermal histories. Later in the Archaean these were juxtaposed and then experienced the same 2700-2500 Ma tectonothermal events. Here we abandon extrapolation of only these four terranes across the whole region, and distinguish two new terranes in the NE. The northernmost Isukasia terrane (previously regarded as the northernmost exposure of the Færingehavn terrane) consists of Palaeoarchaean rocks (>3600 Ma) tectonically bounded on its south by the 3075-2960 …


Complex 3670-3500 Ma Orogenic Episodes Superimposed On Juvenile Crust Accreted Between 3850 And 3690 Ma, Itsaq Gneiss Complex, Southern West Greenland, Clark R L Friend, Allen Phillip Nutman Jan 2005

Complex 3670-3500 Ma Orogenic Episodes Superimposed On Juvenile Crust Accreted Between 3850 And 3690 Ma, Itsaq Gneiss Complex, Southern West Greenland, Clark R L Friend, Allen Phillip Nutman

Faculty of Science - Papers (Archive)

The Itsaq Gneiss Complex of the Nuuk region, southern West Greenland, is dominated by 3850-3690 Ma tonalites intruded into and intercalated with lesser amounts of different ≥3850-3700 Ma supracrustal units. Published wholerock Sr and Nd isotopic studies demonstrate that the tonalites are juvenile crustal additions from a depleted mantle source. From our field studies and SHRIMP U/Pb zircon dating, we argue that this juvenile crustal accretion was spread over ca. 170 m.yr. (≥3850-3690 Ma). Following 3850-3690 Ma juvenile crustal accretion events, the evolution of the Itsaq Gneiss Complex continued with numerous crustal-reworking events between 3670 and 3500 Ma. Examples of …


Metasedimentary Complexes Of The Tuva-Mongolian Massif: Age, Provenances And Tectonic Position, I K Kozakov, E B Sal'nikova, Allen Phillip Nutman, V P Kovach, A B Kotov, V N Podkovyrov, Yu V Plotkina Jan 2005

Metasedimentary Complexes Of The Tuva-Mongolian Massif: Age, Provenances And Tectonic Position, I K Kozakov, E B Sal'nikova, Allen Phillip Nutman, V P Kovach, A B Kotov, V N Podkovyrov, Yu V Plotkina

Faculty of Science - Papers (Archive)

A complex problem of dating supracrustal rocks is unavoidable by analysis of tectonic position of polymetamorphic amphibolite and granulite complexes. Geochronological dates are necessary to constrain ages of source rocks and accumulation periods of clastic sediments, while isotopic-geochemical parameters open a possibility to estimate model ages of the crust in provenances. Using the ion microprobe SHRIMPTM (Hiroshima, Japan), clastic zircons from metasediments of the Erzin and Moren complexes of the Tuva-Mongolian massif in accretionary collage of Central Asia are dated and the Nd model age of respective rocks are estimated. The U-Th-Pb isotopic data suggest that clastic zircons from supracrustal …


Structure Of The Early Palaeozoic Cape River Metamorphics, Tasmanides Of North Queensland: Evaluation Of The Roles Of Convergent And Extensional Tectonics, Christopher L. Fergusson, R A Henderson, K. J. Lewthwaite, D. Phillips, I. W. Withnall Jan 2005

Structure Of The Early Palaeozoic Cape River Metamorphics, Tasmanides Of North Queensland: Evaluation Of The Roles Of Convergent And Extensional Tectonics, Christopher L. Fergusson, R A Henderson, K. J. Lewthwaite, D. Phillips, I. W. Withnall

Faculty of Science - Papers (Archive)

The Early Palaeozoic Cape River Metamorphics consist mainly of psammitic gneiss and schist and occur as an extensive linear belt at the western margin of the Charters Towers Province 200 km southwest of Townsville in the northern Tasmanides. A prominent foliation (S2) is the main structure in the belt and is associated with tight to isoclinal folds, subparallel mineral and intersection lineations, and boudinaged pods of vein quartz and pegmatite. In the southwest, the main foliation is a crenulation cleavage (S2) related to D2 deformation. It overprints steeply dipping foliation (S1) formed in …


Channel Pattern And Deltaic-Estuarine Process In The Indo-Pacific Region, Colin D. Woodroffe Jan 2005

Channel Pattern And Deltaic-Estuarine Process In The Indo-Pacific Region, Colin D. Woodroffe

Faculty of Science - Papers (Archive)

This paper explores the concept that deltaic-estuarine geomorphology is a function of the dominant processes. It has been traditional to recognize river, wave and tidal processes as the principal controls on the gross morphology of deltas. To a lesser extent, these processes are also recognized as significant controls on the shape of estuaries. The complex deltas of the Southeast Asian region contain active deltaic plains and often extensive abandoned deltaic plains which preserve an imprint of the processes which have shaped them. In northern Australia, where estuaries are more extensive than deltas, similar geomorphological features can be recognized and the …


Structure, Detrital Zircon U-Pb Ages And 40ar/39ar Geochronology Of The Early Palaeozoic Girilambone Group, Central New South Wales: Subduction, Contraction And Extension Associated With The Benambran Orogeny, Christopher L. Fergusson, C M Fanning, D. Phillips, Benjamin Ackerman Jan 2005

Structure, Detrital Zircon U-Pb Ages And 40ar/39ar Geochronology Of The Early Palaeozoic Girilambone Group, Central New South Wales: Subduction, Contraction And Extension Associated With The Benambran Orogeny, Christopher L. Fergusson, C M Fanning, D. Phillips, Benjamin Ackerman

Faculty of Science - Papers (Archive)

The Early Palaeozoic Cape River Metamorphics consist mainly of psammitic gneiss and schist and occur as an extensive linear belt at the western margin of the Charters Towers Province 200 km southwest of Townsville in the northern Tasmanides. A prominent foliation (S2) is the main structure in the belt and is associated with tight to isoclinal folds, subparallel mineral and intersection lineations, and boudinaged pods of vein quartz and pegmatite. In the southwest, the main foliation is a crenulation cleavage (S2) related to D2 deformation. It overprints steeply dipping foliation (S1) formed in …


Evidence For Altitude-Dependent Photolysis-Induced 18o Isotopic Fractionation In Stratospheric Ozone, Vanessa E. Haverd, Geoffrey C. Toon, David W. Griffith Jan 2005

Evidence For Altitude-Dependent Photolysis-Induced 18o Isotopic Fractionation In Stratospheric Ozone, Vanessa E. Haverd, Geoffrey C. Toon, David W. Griffith

Faculty of Science - Papers (Archive)

We present vertical profiles of 18O fractionations in ozone, measured by balloon-borne infrared remote sensing between 15 and 40 km. The magnitudes of the 16O16O18O (668O3) and 16O18O16O (686O3) fractionations are 13.5 +/- 2.7% and 7.7 +/- 2.2%, averaged over the 20-35 km altitude range, in good agreement with previous atmospheric measurements by mass spectrometry and both infrared and far infrared remote sensing spectroscopy. We use our fractionation profiles, together with known fractionation effects of the ozone formation reaction, to deduce …


A Survey Of Martian Dust Devil Activity Using Mars Global Surveyor Mars Orbiter Camera Images, Jenny A. Fisher, Mark I. Richardson, Claire E. Newman, Mark A. Szwast, Chelsea Graf, Shabari Basu, Shawn P. Ewald, Anthony D. Toigo, R. John Wilson Jan 2005

A Survey Of Martian Dust Devil Activity Using Mars Global Surveyor Mars Orbiter Camera Images, Jenny A. Fisher, Mark I. Richardson, Claire E. Newman, Mark A. Szwast, Chelsea Graf, Shabari Basu, Shawn P. Ewald, Anthony D. Toigo, R. John Wilson

Faculty of Science - Papers (Archive)

A survey of dust devils using the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide- and narrow-angle (WA and NA) images has been undertaken. The survey comprises two parts: (1) sampling of nine broad regions from September 1997 to July 2001 and (2) a focused seasonal monitoring of variability in the Amazonis region, an active dust devil site, from March 2001 to April 2004. For part 1, dust devils were identified in NA and WA images, and dust devil tracks were identified in NA images. Great spatial variability in dust devil occurrence is highlighted, with Amazonis Planitia being the …


High Spectral Resolution Solar Absorption Measurements Of Ethylene (C2h4) In A Forest Fire Smoke Plume Using Hitran Parameters: Troposheric Vertical Profile Retrieval, Curtis P. Rinsland, Clare Paton-Walsh, Nicholas B. Jones, David W. T Griffith, Aaron Goldman, Stephen W. Wood, Linda Chiou, Arndt Meier Jan 2005

High Spectral Resolution Solar Absorption Measurements Of Ethylene (C2h4) In A Forest Fire Smoke Plume Using Hitran Parameters: Troposheric Vertical Profile Retrieval, Curtis P. Rinsland, Clare Paton-Walsh, Nicholas B. Jones, David W. T Griffith, Aaron Goldman, Stephen W. Wood, Linda Chiou, Arndt Meier

Faculty of Science - Papers (Archive)

The tropospheric mixing ratio profile of ethylene (C2H4)(C2H4) has been retrieved from a high spectral resolution ground-based infrared solar absorption spectrum. The spectrum was recorded during intense fires in New South Wales, Australia on January 1, 2002, and was analyzed with the C2H4C2H4 spectral parameters added to the 2000 HITRAN compilation. Absorption by C2H4C2H4 in the smoke-affected spectrum extends over a broad spectral range in a region with observable rotational fine structure. The fine structure occurs in addition to the View the MathML source949.5cm-1ν7ν7 band Q branch that is traditionally used to quantify C2H4C2H4 amounts from infrared atmospheric measurements assuming …