Corrigendum to “Total mercury body burden in Pacific harbor seal, Phoca vitulina richardii, pups from central California” [Marine Pollution Bulletin 56 (2008) 27–41]     

Tiffini J. Brookens  Todd M. O’Hara  Robert J. Taylor  Gerald R. Bratton  James T. Harvey 《Marine pollution bulletin》2009,58(12):1953

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A new approach to develop the Raman carbonaceous material geothermometer for low‐grade metamorphism using peak width     

Yui Kouketsu  Tomoyuki Mizukami  Hiroshi Mori  Shunsuke Endo  Mutsuki Aoya  Hidetoshi Hara  Daisuke Nakamura  Simon Wallis 《Island Arc》2014,23(1):33-50

The Raman spectra of carbonaceous material (CM) from 19 metasediment samples collected from six widely separated areas of Southwest Japan and metamorphosed at temperatures from 165 to 655°C show systematic changes with metamorphic temperature that can be classified into four types: low‐grade CM (c. 150–280°C), medium‐grade CM (c. 280–400°C), high‐grade CM (c. 400–650°C), and well‐crystallized graphite (> c. 650°C). The Raman spectra of low‐grade CM exhibit features typical of amorphous carbon, in which several disordered bands (D‐band) appear in the first‐order region. In the Raman spectra of medium‐grade CM, the graphite band (G‐band) can be recognized and several abrupt changes occur in the trends for several band parameters. The observed changes indicate that CM starts to transform from amorphous carbon to crystallized graphite at around 280°C, and this transformation continues until 400°C. The G‐band becomes the most prominent peak at high‐grade CM suggesting that the CM structure is close to that of well‐crystallized graphite. In the highest temperature sample of 655°C, the Raman spectra of CM show a strong G‐band with almost no recognizable D‐band, implying the CM grain is well‐crystallized graphite. In the Raman spectra of low‐ to medium‐grade CM, comparisons of several band parameters with the known metamorphic temperature show inverse correlations between metamorphic temperature and the full width at half maximum (FWHM) of the D1‐ and D2‐bands. These correlations are calibrated as new Raman CM geothermometers, applicable in the range of c. 150–400°C. Details of the methodology for peak decomposition of Raman spectra from the low to medium temperature range are also discussed with the aim of establishing a robust and user‐friendly geothermometer.  相似文献   

Increases of wet deposition at remote sites in Japan from 1991 to 2009     

Kyo Kitayama  Sinya Seto  Manabu Sato  Hiroshi Hara 《Journal of Atmospheric Chemistry》2012,69(1):33-46

Temporal trends in wet deposition of major ions were explored at nationwide remote sites in Japan from April 1991 to March 2009 by using the seasonal Kendall slope estimator and the nonparametric seasonal Kendall test. For the trend analysis, datasets from eight remote sites (Rishiri, Echizenmisaki, Oki, Ogasawara, Shionomisaki, Goto, Yakushima, and Amami) were selected from the Japanese Acid Deposition Survey (JADS) conducted by the Ministry of the Environment. Deposition of H⁺ has been increasing at remote sites in Japan on a national scale. Significant (p????0.05) increases in H⁺ deposition were detected with changes of +3?C+9?%?year^?1 at seven sites, while insignificant increases were observed at one site. Depositions of non-sea salt (nss)-SO ₄ ^2? and NO ₃ ^? significantly increased at four and six sites, respectively, with changes of +1?C+3?%?year^?1. Significant increases in precipitation at four sites would have contributed to the increase in depositions of H⁺, nss-SO ₄ ^2? , and NO ₃ ^? . The emission trends of SO₂ and NO_x did not corresponded to the deposition trends of nss-SO ₄ ^2? and NO ₃ ^? . The different trends indicated that temporal variation of precipitation amount trend dominated the deposition trends.  相似文献   

Effects of sheens associated with offshore oil and gas development on the feather microstructure of pelagic seabirds     

Patrick D. O’Hara  Lora A. Morandin 《Marine pollution bulletin》2010,60(5):672-678

Operational discharges of hydrocarbons from maritime activities can have major cumulative impacts on marine ecosystems. Small quantities of oil (i.e., 10 ml) results in often lethally reduced thermoregulation in seabirds. Thin sheens of oil and drilling fluids form around offshore petroleum production structures from currently permissible operational discharges of hydrocarbons. Methodology was developed to measure feather microstructure impacts (amalgamation index or AI) associated with sheen exposure. We collected feather samples from two common North Atlantic species of seabirds; Common Murres (Uria aalge) and Dovekies (Alle alle). Impacts were compared after feather exposure to crude oil and synthetic lubricant sheens of varying thicknesses. Feather weight and microstructure changed significantly for both species after exposure to thin sheens of crude oil and synthetic drilling fluids. Thus, seabirds may be impacted by thin sheens forming around offshore petroleum production facilities from discharged produced water containing currently admissible concentrations of hydrocarbons.  相似文献   

A probabilistic approach to exposure risk assessment   总被引：1，自引：1，他引：0  

Crispin M. Mutshinda  Imoh Antai  Robert B. O’Hara 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(4):441-449

The introduction of hazardous substances into the environment has long been recognized as being a cause of several diseases in humans, wildlife, and plants. The damaging character of suspected contaminants is usually assessed via a “reject/retain” design with no explicit link between levels of exposure and intensities of the potential adverse health effects even though this connection may be important for the development of public health regulations that limit exposure to hazardous substances. Here, we propose a probabilistic approach to exposure risk assessment as a way around this typical flaw. We develop a Bayesian model using proximity to the source of an alleged contaminant as a surrogate for exposure. Subsequently, we carry out an experimental study based on simulated data to illustrate the model implementation with real world data. We also discuss a possible way of extending the model to accommodate potential heterogeneity in the spatial distribution of the focal disease.  相似文献   

Polarization Calibration of the <Emphasis Type="Italic">Chromospheric Lyman-Alpha SpectroPolarimeter</Emphasis> for a 0.1% Polarization Sensitivity in the VUV Range. Part II: In-Flight Calibration     

G. Giono  R. Ishikawa  N. Narukage  R. Kano  Y. Katsukawa  M. Kubo  S. Ishikawa  T. Bando  H. Hara  Y. Suematsu  A. Winebarger  K. Kobayashi  F. Auchère  J. Trujillo Bueno  S. Tsuneta  T. Shimizu  T. Sakao  J. Cirtain  P. Champey  A. Asensio Ramos  J. Štěpán  L. Belluzzi  R. Manso Sainz  B. De Pontieu  K. Ichimoto  M. Carlsson  R. Casini  M. Goto 《Solar physics》2017,292(4):57

The Chromospheric Lyman-Alpha SpectroPolarimeter is a sounding rocket instrument designed to measure for the first time the linear polarization of the hydrogen Lyman-\({\upalpha }\) line (121.6 nm). The instrument was successfully launched on 3 September 2015 and observations were conducted at the solar disc center and close to the limb during the five-minutes flight. In this article, the disc center observations are used to provide an in-flight calibration of the instrument spurious polarization. The derived in-flight spurious polarization is consistent with the spurious polarization levels determined during the pre-flight calibration and a statistical analysis of the polarization fluctuations from solar origin is conducted to ensure a 0.014% precision on the spurious polarization. The combination of the pre-flight and the in-flight polarization calibrations provides a complete picture of the instrument response matrix, and a proper error transfer method is used to confirm the achieved polarization accuracy. As a result, the unprecedented 0.1% polarization accuracy of the instrument in the vacuum ultraviolet is ensured by the polarization calibration.  相似文献   

Detrital zircon multi‐chronology,provenance, and low‐grade metamorphism of the Cretaceous Shimanto accretionary complex,eastern Shikoku,Southwest Japan: Tectonic evolution in response to igneous activity within a subduction zone          下载免费PDF全文

Hidetoshi Hara  Yoshihiro Nakamura  Kousuke Hara  Toshiyuki Kurihara  Hiroshi Mori  Hideki Iwano  Tohru Danhara  Shuhei Sakata  Takafumi Hirata 《Island Arc》2017,26(6)

Detrital zircon multi‐chronology combined with provenance and low‐grade metamorphism analyses enables the reinterpretation of the tectonic evolution of the Cretaceous Shimanto accretionary complex in Southwest Japan. Detrital zircon U–Pb ages and provenance analysis defines the depositional age of trench‐fill turbidites associated with igneous activity in provenance. Periods of low igneous activity are recorded by youngest single grain zircon U–Pb ages (YSG) that approximate or are older than the depositional ages obtained from radiolarian fossil‐bearing mudstone. Periods of intensive igneous activity recorded by youngest cluster U–Pb ages (YC1σ) that correspond to the younger limits of radiolarian ages. The YC1σ U–Pb ages obtained from sandstones within mélange units provide more accurate younger depositional ages than radiolarian ages derived from mudstone. Determining true depositional ages requires a combination of fossil data, detrital zircon ages, and provenance information. Fission‐track ages using zircons estimated YC1σ U–Pb ages are useful for assessing depositional and annealing ages for the low‐grade metamorphosed accretionary complex. These new dating presented here indicates the following tectonic history of the accretionary wedge. Evolution of the Shimanto accretionary complex from the Albian to the Turonian was caused by the subduction of the Izanagi plate, a process that supplied sediments via the erosion of Permian and Triassic to Early Jurassic granitic rocks and the eruption of minor amounts of Early Cretaceous intermediate volcanic rocks. The complex subsequently underwent intensive igneous activity from the Coniacian to the early Paleocene as a result of the subduction of a hot and young oceanic slab, such as the Kula–Pacific plate. Finally, the major out‐of‐sequence thrusts of the Fukase Fault and the Aki Tectonic Line formed after the middle Eocene, and this reactivation of the Shimanto accretionary complex as a result of the subduction of the Pacific plate.  相似文献   

Characterization of sulfate mineral deposits in central Thailand          下载免费PDF全文

Junichiro Kuroda  Hidetoshi Hara  Katsumi Ueno  Thasinee Charoentitirat  Teruyuki Maruoka  Takashi Miyazaki  Akira Miyahigashi  Stefano Lugli 《Island Arc》2017,26(2)

In this paper we present petrographic and geochemical data of sulfate mineral deposits in northeast Nakhon Sawan, central Thailand, and provide new constraints on their age. The deposits are made up mainly of strongly deformed nodular and massive gypsum in the upper part, and less deformed layered anhydrite in the lower part. They are intruded by andesitic dikes that contain Middle Triassic zircons (ca 240 Ma). These dikes are probably part of the regional magmatic activity of the Sukhothai Arc during the Early to Middle Triassic. Sulfur (δ³⁴S) and strontium (⁸⁷Sr/⁸⁶Sr) isotopic compositions of the sulfates range from 15.86 ‰ to 16.26 ‰ and from 0.70810 to 0.70817, respectively. Comparisons with the Phanerozoic seawater isotopic evolution curve indicate that those values are best explained by precipitation of the sulfates from Carboniferous seawater, in particular seawater of late Mississippian age (ca 326 Ma), and this would be consistent with previous studies of calcareous fossils in the limestones that crop out around this site. Our interpretation is that evaporitic gypsum was originally precipitated from hypersaline seawater on a shallow lagoon or shelf on the Khao Khwang Platform during the Serpukhovian, and that this gypsum changed to anhydrite during early burial. The anhydrite was then cut by andesitic dikes during the Middle Triassic, and more recently the upper part of which was rehydrated during exhumation to form secondary gypsum near the surface.  相似文献   

Recent and historical tsunami deposits from Lake Tokotan,eastern Hokkaido,Japan, inferred from nondestructive,grain size,and radioactive cesium analyses     

Shinozaki  Tetsuya  Sawai  Yuki  Ito  Kazumi  Hara  Junko  Matsumoto  Dan  Tanigawa  Koichiro  Pilarczyk  Jessica E. 《Natural Hazards》2020,103(1):713-730

Geological evidence of recent tsunamis from sediment samples collected from Lake Tokotan, a coastal lagoon in eastern Hokkaido, northern Japan, was detected using computed tomography (CT) and soft X-ray images, grain size, and radionuclide profiles. Initial field observations revealed that sediments had no discernable sedimentary structures at the top of the core. However, results of CT imaging, soft X-ray, and grain size analyses show evidence for three invisible sand layers that are intercalated with mud layers. These sand layers exhibit trends of landward fining and thinning. Furthermore, the distribution of sand layers was limited to the center and seaward parts of the lake. Vertical profiles of cesium and lead concentrations in combination with recent eyewitness accounts indicated that these sand layers are correlated with the 1973 Nemuro-oki, 1960 Chilean, and 1952 Tokachi-oki tsunami events. The deeper part of the sediment cores includes three volcanic ash layers and three prehistoric coarse sand layers. The prehistoric layers are correlated with unusually large tsunamis that were geologically identified in previous studies from eastern Hokkaido. These findings suggest that nondestructive techniques, in combination with radionuclide analysis, allow for detection of frequent but faint tsunami deposits. This technique allows for an improved understanding of the history of tsunami inundation in Lake Tokotan and of other locations for which stratigraphic evidence for faint tsunamis layers is not readily apparent from field assessments.

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Transdisciplinary co-operation for an ecosystem approach to fisheries: A case study from the South African sardine fishery     

B. Paterson  M. Isaacs  M. Hara  A. Jarre  C.L. Moloney 《Marine Policy》2010

Integrative approaches that involve natural and social scientists are needed to manage fisheries, but these are difficult to achieve. The process of developing a prototype, knowledge-based, electronic decision support tool for the South African sardine Sardinops sagax fishery provided a platform for fostering collaboration and achieving active participation of many stakeholders. The aim of the decision support tool is to assist managers in evaluating how effectively an ecosystem approach to fisheries (EAF) has been implemented for this fishery. The collaborative process involved a series of meetings during which knowledge was elicited from fisheries scientists, social scientists, resource managers and fishing industry representatives. Conceptualisations of the different stakeholder perspectives were developed in terms of objectives and indicators following the hierarchical tree approach recommended by FAO. This paper describes the collaborative process. Hierarchies of objectives, indicators and data sets for the human dimension of an EAF in the South African sardine fishery are introduced. The value of a transdisciplinary approach towards an EAF in South Africa is discussed.  相似文献