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Testing atmospheric monitoring techniques for geological storage of CO2
No full textThe success of CO2 geological storage in mitigating climate change will depend on its ability to
withhold large amounts of CO2 from the atmosphere over centuries or more. Atmospheric
techniques have been used to monitor Australia’s first geosequestration project, the CO2CRC
Otway Project, since its inception (Etheridge et al. 2011; Jenkins et al. 2011). These techniques
have been developed to be sensitive (detecting small potential leakage signals against large and
variable background CO2 concentrations and fluxes), specific (attributing variations to sources
using chemical and isotopic fingerprints and dispersion modelling) and practical (continuous
remote operation) (Leuning et al. 2008; Luhar et al. 2009). A recent stage of the Otway project
involved periods of controlled releases of injected gas at the surface that could mimic leakage.
This provided a test of the original atmospheric scheme, complemented by additional
measurements of CO2 and CH4 concentrations and carbon isotopes of CO2.
Based on the experience at Otway and recent results from the new Arcturus baseline
atmospheric station in Queensland, this presentation will consider the potential merits of
atmospheric techniques for monitoring greenhouse gas emissions from emerging energy
technologies such as geosequestration and coal seam methane. © 2011 CSIRO and the Bureau of Meteorology
Extreme wave deposits on the Pacific Coast of Mexico: tsunamis or storms? - A multi-proxy approach
No full textHistorical and instrumental data show that the Pacific coast of Mexico has been exposed to destructive tsunamis over at least the past 500 years. This coast is also affected by hurricanes generated in the eastern Pacific. The great 1985 Mexico earthquake and its aftershock generated tsunamis that affected the Ixtapa-Zihuatanejo and Michoacán coast. The purpose of our study was two-fold, a) to determine whether we could distinguish storm from tsunami deposits, and b) whether tsunami deposits from historical events are preserved in the tropical environments of the Ixtapa-Zihuatanejo coast. Two anomalous sand units in the Ixtapa estuary are interpreted as the result of high-energy marine inundation events that occurred in the last century. Several lines of evidence using a multi-proxy approach (historical studies, interviews with local witnesses, geomorphological and geological surveys, coring and trenching, and laboratory analyses including grain size, micropaleontology, geochemistry, magnetic susceptibility and radiometric dating) indicate the occurrence of two tsunamis that we link to local events: the 1985 Mexico and possibly the 1979 Petatlan earthquakes. We thereby provide the first onshore geological evidence of historical tsunamis on the Pacific coast of Mexico. © American Geophysical Unio
Lower Hunter particle characterisation study appendices to the final report to the NSW Environment Protection Authority
No full textThe Lower Hunter Particle Characterisation Study was commissioned by the NSW Environment Protection Authority in 2013 to investigate the composition and major sources of particle pollution in the Lower Hunter. The study was conducted by scientists from the former Office of Environment and Heritage (OEH), CSIRO and the Australian Nuclear Science and Technology Organisation (ANSTO), with oversight from the NSW Ministry of Health, and completed in 2016. Focusing on very small particles, invisible to the human eye, which can be inhaled and can pass through the throat and nose and into the lungs, the study aimed to determine the composition and major sources of fine particles (PM2.5) and coarse particles (PM2.5-10). Fine particles were monitored at four sites, including two sites representative of regional population exposures (Newcastle, Beresfield) and two sites near the Port of Newcastle (Mayfield and Stockton). Coarse particles were monitored at Mayfield and Stockton, the two sites near the Port of Newcastle
Late Holocene Fire History & Palaeoecological Conditions at Dunphy Lake, Warrumbungle National Park, New South Wales, Australia
No full textThere is a significant geographical and temporal gap in the Holocene environmental record of fire, hydrology and palaeoecological conditions in the region of the Warrumbungle Mountains in eastern Australia. Dunphy Lake (-31.3076°S, 149.0149°E) is a small, ephemeral freshwater wetland within Warrumbungle National Park, and the only example of its kind in this temperate -semiarid region. Late Holocene fire history and palaeoecological conditions at Dunphy Lake were determined using a multiproxy approach that incorporates geochronological, limnological and geochemical techniques. The sediment profile at Dunphy Lake is dominated by mud (< 63 µm) and the macrocharcoal record indicates that the largest local fire events have occurred since 1,793±28 years BP. Some distinct peaks in macrocharcoal are coincident with peaks in sand (63-2000 µm) content, suggesting that some fires occurred at similar times to episodes of significant runoff and sediment flux from the catchment. Recent palaeoecological conditions were conducive to a relatively complex aquatic food web, as shown by the presence of micro- and macro-invertebrate and diatom remains in the upper sediment facies. A geochemical record derived from ITRAX core scanning shows facies with elevated pedogenic (e.g. Mn, Ca) and detrital (e.g. Si, Ti) elements, but does not show a significant increase in anthropogenic elements at the surface. Altogether, this multiproxy approach yields a record of fire and aquatic conditions that can be used to place historical and contemporary fires and vegetation changes in this region into context
Possible paleo-tsunami deposits at Rikuzentakata City, Japan
No full textRikuzentakata City, NE Japan, has been repeatedly suffered by tsunami inundations including 1896 Meiji-Sanriku, 1933 Showa-Sanriku, 1960 Chilean Tsunami, and 2011 Tohoku-Oki Tsunami. Up to 30 cm thick sand layer was deposited by the 2011 tsunami in this city (Naruse et al., 2012). Our study indicates that historical and prehistoric tsunamis also left deposits in this area. Nevertheless, previous studies of paleo-tsunami deposits in this area are limited (Haraguchi et al., 2006, Imaizumi et al., 2007), because of the difficulty of finding paleo-tsunami deposits along this ""ria"" coast.
We conducted a field survey using a geoslicer to acquire sediment cores in order to explore the magnitude and history of tsunamis in this area. Overall 10 cores, each 2 m long and 12 cm wide were acquired during the survey. The sedimentary sequences were mostly composed of peaty soil, which was thought to have been deposited in a marsh environment, however these soils units were inter-fingered by numerous 1-15 cm thick sand layers. According to initial work including grain size analysis, some of the sand layers deposited 1.4 km from the present shoreline are identified as having a possible tsunami origin because they tend to show upward fining characteristics, indicating rapid sedimentation from suspended load. We will also present the preliminary results of tephra chronology, radiocarbon and 210Pb dating, and diatom analysis.Possible paleo-tsunami deposits at Rikuzentakata City, Japa
Southwest Australian speleothem records – an update
No full textSouthwest Western Australia (SWWA) experienced a clear climatic change during
the late 20thC and has been identified as highly vulnerable to future climate change
(Hope et al., 2010). Paleoclimate records could assist in understanding SWWA
climate but very few exist for this region. Early investigations into speleothems were
very promising, demonstrating that speleothem-based proxies record the multidecadal reduction in rainfall since the 1970s (Treble et al., 2003, 2005; Fischer and
Treble, 2008). Subsequent efforts to build a paleoclimate record revealed that the
climate-speleothem signal was poorly understood in our studied cave e.g.
disagreement between coeval records; non-linear response in the speleothem-climate
signal. To address this, a cave monitoring program was launched in 2005 involving
instrumentation of Golgotha Cave and monthly drip water collection. We present a
summary of these findings during 2005-2013 from two contrasting high and low-flow
drip sites, as well as our progress on building a high-resolution climate record
spanning the last ~600 years
Using trace element and halide isotopes to understand salinization mechanisms of groundwaters from an arid aquifer
Full text linkSaline groundwaters are common to inland Australia, yet many aspects of their hydrochemical evolution remain uncertain. The saline groundwaters in the alluvial aquifers of the Darling River have previously been found to exhibit broad similarity in traditional hydrochemical and isotopic tracers. By contrast, trace element isotopes (δ7Li, δ11B and 87Sr/86Sr) and halide isotopes (δ37Cl and δ81Br) provide evidence of more complex hydrogeochemical processes.Hydrochemical evolution was found to be dependent on proximity to theDarling River and depth even though all groundwaters from this aquifer were found to be saline. The differing signatures highlighted the discovery of adeeper palaeo-groundwater system containing heavier trace element and halide isotope values. The measurement of these isotopes has permitted delineation of groundwater end-members and salinization mechanisms that would have otherwise not been identified
THERMEC 2018 : 10th International Conference on Processing and Manufacturing of Advanced Materials
No full textThis book presents the proceedings of the THERMEC’2018: 10th International Conference on Processing and Manufacturing of Advanced Materials, which took place between July 09 and July 13, 2018 in Paris, France, under the co-sponsorship of Universite de Lille, MINES ParisTech, PSL and Universite de Tours, France. The presented book will be useful for many researchers and engineers/technologists working in different aspects of processing and fabrication of materials, structure/property evaluation and applications of both ferrous and nonferrous materials including biomaterials, smart materials as well as the advanced measurement techniques in the materials sciene
Ochre through the late Quaternary at Gledswood Shelter 1, northwest Queensland
No full textGledswood Shelter 1 (GS1) is a sandstone rockshelter located in northwest Queensland containing
archaeological evidence for human occupation dating from at least 35 ka to the recent past.
Considerable quantities of ochre fragments (many with striations caused by grinding) have been
recovered from the 2.5 m deep cultural sequence, particularly in the pre-LGM levels. The abundance
of ochre varies through time, in line with recovered stone artefacts, suggesting that these materials
reflect different periods and intensities of site use. This evidence possibly indicates that the production
of painted or stencilled art in this region may be earlier than previous evidence suggests (ca 9,000
years ago). The GS1 ochre samples were initially characterised according to visual characteristics
including colour, texture and inclusions using low powered microscopy. This work suggests there are
several groups of pigment present, including fragments that would more normally be referred to as
ironstone and not considered as an 'ochre', but that have anthropogenic ground surfaces indicating
their use as a source of pigment. In this paper we present the initial characterisation and preliminary
neutron activation analysis results of the GS1 ochres, and consider their implications for the human
history of the northwest Queensland region
Analysis of a decade of Asian outflow of PM10 and TSP to Gosan, Korea: also incorporating Radon-222
No full textTen years of aerosol and Radon–222 (radon) data from Gosan, Korea, were analyzed. Seasonal cycles were strongly linked to changes in fetch and time of year. We estimated that 7.21 t/m y of PMio aerosol pass Gosan in the atmospheric boundary layer, increasing annually by 0.3 t/m y. Contributions to aerosol loading were characterized by fetch: South China, North China, Korea and Japan. While the highest, and most variable, contributions typically originated from South China, these air masses contributed to only 6% of the overall dataset. PM10 distributions were broader from South and North China than for Korea or Japan, reflecting differences in natural/anthropogenic soil sources, and number/distribution of large point sources. Employing radon to select air masses more representative of targeted fetch regions typically resulted in greater reported pollutant concentrations and rates of change over the decade. Estimated rates of PM10 increase from North China and Korea over the decade were 1.4 and 0.9 μg/m3 y, respectively. Total suspended particulate (TSP) elemental analysis indicated that the (non–sea–salt) nss–SO42− content of aerosols has been gradually increasing over the past decade and more recently an increase in NO3− was seen. However, on average, rates of increase in nss–SO42− have reduced since 2007, which were higher in South than North China. © 2020 Elsevier B.V