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multifractal modelling and spectrum analysis: methods and applications to gamma ray spectrometer data from southwestern Nova Scotia, canada

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science China earth sciences 2006年第3期49卷 283-294页

作者： CHENG Qiuming1,2.1. State Key Lab of Geological processes and mineral Resources, China university of Geosciences, Wuhan 430074, China {2., department of geography, york university, 4700 keele street, toronto, ontario, m3j 1p3, canada State Key Lab of Geological processes and mineral Resources China University of Geosciences Wuhan China department of earth and {2. science and engineering Department of Geography York University Toronto Canada

multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2.nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova Scotia, canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (K) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/K and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, K, U/Th and U/K consistently show two distinct power-law relationships for two ranges of wave number 12.ω ≤160 km and 0≤ω ≤12.km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIS.

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Ground-based and additional science support for SmILE

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earth and planetary physics 2024年第1期8卷 275-298页

作者： j.A.Carter m.Dunlop C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.milan T.Sergienko R.C.Fear D.G.Sibeck m.Connors T.Yeoman X.Tan m.G.G.T.Taylor K.mcWilliams j.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock m.p.Freeman D.-S.Han m.D.Hartinger S.-Y.W.Hsieh Z.-j.Hu m.K.james L.juusola K.Kauristie E.A.Kronberg m.Lester j.manuel j.matzka I.mcCrea Y.miyoshi j.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun m.-T.Walach B.Walsh C.Wang j.Weygand j.Wild j.Yan j.Zhang Q.-H.Zhang planetary sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton Laboratory space Science Technology Facilities CouncilOxfordshireUK School of space and Environment Beihang UniversityBeijing 100191China Key Laboratory of space Environment monitoring and Information processing Ministry of Industry and Information TechnologyBeijing 100017China department of space and Climate physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for space science Department of Physics and Technology.University of BergenBergenNorway department of physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of space physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard space Flight Center NASAGreenbeltMarylandUSA Athabasca university AthabascaCanada ESTEC European Space AgencyNetherlands university of Saskatchewan SaskatoonCanada The johns Hopkins university Applied physics Laboratory LaurelMarylandUSA Swedish Institude of space physics UppsalaSE 75121Sweden Tongji university Shanghai 200092China Center for space plasma physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA polar Research Institute of China Shanghai 200136China Finnish meteorological Institute(FmI) Finland department of earth and Environmental {2.s(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian space Agency MontrealCanada GFZ German Research Centre for Geosciences PotsdamGermany Nagoya university Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria university Newcastle upon TyneTyne and WearUK NE18ST National space science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European space Agency and Chinese Academy of sciences Solar wind magnetosphere Ionosphere Link Explorer(SmILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SmILE ***,we describe current community efforts to prepare for SmILE,and the benefits and context various experiments that have explicitly expressed support for SmILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional science Working Group,is facilitating these *** include constructing an online SmILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SmILE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SmILE conjunctions missions

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Oil-bearing fluid inclusions from the palaeoproterozoic:A review of biogeochemical results from time-capsules >2.0 Ga old

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science China earth sciences 2009年第1期52卷 1-11页

作者： Simon C. GEORGE Adriana DUTKIEWICZ Herbert VOLK john RIDLEY David j. mOSSmAN Roger BUICK department of earth and planetary {2.s Macquarie University School of Geosciences University of Sydney CSIRO petroleum department of Geosciences Colorado State University department of geography Mount Allison University department of earth and {2. sciences & Astrobiology program University of Washington

The observation of oil inclusions trapped prior to 2.0 Ga in palaeoproterozoic rocks and the ability to obtain detailed molecular geochemical information from them provide a robust way for understanding the early biog... 详细信息

关键词： palaeoproterozoic fluid inclusion oil biomarker blank

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Strategies towards robust interpretations of in situ zircon oxygen isotopes

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Geoscience Frontiers 2023年第2期14卷 241-255页

作者： janne Liebmann Christopher L.Kirkland john B.Cliff Christopher j.Spencer Aaron j.Cavosie Timescales of mineral Systems Group The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin UniversityPerthAustralia pacific Northwest National Laboratory RichlandWashington 99354United States department of Geological sciences and Geological {2. Queen’s UniversityKingstonONCanada space science and Technology Centre The Institute for Geoscience Research(TIGeR)School of Earth and Planetary ScienceCurtin UniversityPerthAustralia

Oxygen isotopes are a versatile tool to address a wide range of questions in the earth *** include geothermometry,paleoclimatology,tracing of geochemical reservoirs,fluid-rock interaction,magmatic petrogenesis,and identification of extra-terrestrial *** arguably provides one of the most robust records of primary magmatic O isotope ratio due to low diffusion rates in crystalline *** ability to correlate zircon O isotopes with temporal and petrogenetic information(e.g.U-pb geochronology,Lu-Hf isotopes,and trace elements)makes this mineral a key archive for understanding earth’s crustal ***,zircon O isotope geochemistry has found widespread usage to address fundamental questions across the earth and planetary *** general apparent ease of O isotopic acquisition through the advancement of rapid in situ techniques(*** ion mass spectrometry;SImS)and associated dedicated national laboratories has led to the generation of large O isotopic data sets of variable quality,highlighting the importance of a coherent workflow for data collection,reduction,and *** paper presents a set of approaches for measurement,assessment,and reporting of zircon O isotope *** focus in this contribution is on in situ analysis via secondary ion mass spectrometry using large geometry instruments,but other commonly used techniques are briefly reviewed for *** work aims to provide an analytical framework necessary for geologically meaningful interpretation of O isotope *** addition,we describe inherent geological(***-induced disturbance of the zircon O isotopic system)and analytical(*** due to sample topography effects)challenges and outline means to identify and avoid such issues as a prerequisite to the generation of robust primary O isotopic signatures for geological interpretation.

关键词： In situ Oxygen isotopes Zircon SImS Secondary ion mass spectrometry Off-mount standard

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An earth-mass planet in a time of COVID-19:KmT-2.2.-BLG-0414Lb

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Research in Astronomy and Astrophysics 2021年第9期21卷 243-261页

作者： Weicheng Zang Cheongho Han Iona Kondo jennifer C.Yee Chung-Uk Lee Andrew Gould Shude mao Leandro de Almeida Yossi Shvartzvald Xiangyu Zhang michael D.Albrow Sun-ju Chung Kyu-Ha Hwang Youn Kil jung Yoon-Hyun Ryu In-Gu Shin Sang-mok Cha Dong-jin Kim Hyoun-Woo Kim Seung-Lee Kim Dong-joo Lee Yongseok Lee Byeong-Gon park Richard W.pogge john Drummond Thiam-Guan Tan joséDias do Nascimento júnior Dan maoz matthew T.penny Wei Zhu Ian A.Bond Fumio Abe Richard Barry David p.Bennett Aparna Bhattacharya martin Donachie Hirosane Fujii Akihiko Fukui Yuki Hirao Yoshitaka Itow Rintaro Kirikawa Naoki Koshimoto man Cheung Alex Li Yutaka matsubara Yasushi muraki Shota miyazaki Greg Olmschenk Clément Ranc Nicholas j.Rattenbury Yuki Satoh Hikaru Shoji Stela Ishitani Silva Takahiro Sumi Daisuke Suzuki Yuzuru Tanaka paul j.Tristram Tsubasa Yamawaki Atsunori Yonehara Andreea petric Todd Burdullis pascal Fouqué department of Astronomy Tsinghua UniversityBeijing 100084China department of physics Chungbuk National UniversityCheongju 28644Republic of Korea department of earth and {2. science Graduate School of ScienceOsaka UniversityToyonakaOsaka 560-0043Japan Center for Astrophysics j Harvard&Smithsonian 60 Garden St.CambridgeMA 02138USA Korea Astronomy and space science Institute Daejon 34055Republic of Korea university of science and Technology Korea(UST)217 Gajeong-ro Yuseong-guDaejeon 34113Republic of Korea max-planck-Institute for Astronomy Königstuhl 1769117 HeidelbergGermany department of Astronomy Ohio State University140 W.18th Ave.ColumbusOH 43210USA National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Universidade Federal do Rio Grande do Norte(UFRN) Departamento de F´1sica59078-970NatalRNBrazil department of particle physics and Astrophysics Weizmann Institute of ScienceRehovot 76100Israel university of Canterbury Department of Physics and AstronomyPrivate Bag 4800Christchurch 8020New Zealand School of space Research Kyung Hee UniversityYonginKyeonggi 17104Republic of Korea possum Observatory PatutahiGisbourneNew Zealand perth Exoplanet Survey Telescope PerthAustralia School of physics and Astronomy Tel-Aviv UniversityTel-Aviv 6997801Israel department of physics and Astronomy Louisiana State UniversityBaton RougeLA 70803 USA Canadian Institute for Theoretical Astrophysics University of Toronto60 St George StreetTorontoON M5S 3H8Canada Institute of Natural and mathematical sciences Massey UniversityAuckland 0745New Zealand Institute for space-earth Environmental Research Nagoya UniversityNagoya 464-8601Japan Code 667 NASA Goddard Space Flight CenterGreenbeltMD 20771USA department of Astronomy University of MarylandCollege ParkMD 20742USA department of physics University of AucklandPrivate Bag 92019AucklandNew Zealand department of earth and planetary {2. Graduate School of ScienceThe University of Tokyo7-3-1 Hongo

We report the discovery of KmT-2.2.-BLG-0414 Lb,with a planet-to-host mass ratio q2.0.9-1.2.10-5=3-4 q⊕at 1σ,which is the lowest mass-ratio microlensing planet to *** with two other recent discoveries(4?q/q⊕?6),it fills out the previous empty sector at the bottom of the triangular(log s,log q)diagram,where s is the planet-host separation in units of the angular Einstein radiusθ***,these discoveries call into question the existence,or at least the strength,of the break in the mass-ratio function that was previously suggested to account for the paucity of very low-q *** to the extreme magnification of the event,Amax~1450 for the underlying single-lens event,its light curve revealed a second companion with q3~0.05 and|log s3|~1,i.e.,a factor~10 closer to or farther from the host in *** measurements of the microlens parallaxπE and the angular Einstein radiusθE allow estimates of the host,planet and second companion masses,(m1,m2.m3)~(0.3 m⊙,1.0 m⊕,17 mj),the planet and second companion projected separations,(a⊥,2.a⊥,3)~(1.5,0.15 or 15)au,and system distance DL~1 *** lens could account for most or all of the blended light(I~19.3)and so can be studied immediately with high-resolution photometric and spectroscopic observations that can further clarify the nature of the *** planet was found as part of a new program of high-cadence follow-up observations of high-magnification *** detection of this planet,despite the considerable difficulties imposed by COVID-19(two KmT sites and OGLE were shut down),illustrates the potential utility of this program.

关键词： gravitational lensing:micro

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The Black Sea Dating Game and Holocene marine Transgression

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Open journal of marine science 2014年第1期4卷 1-7页

作者： peta j. mudie Valentina Yanko-Hombach Sergei Kadurin department of physical and marine Geology Odessa I.I. Mechnikov National University Odessa Ukraine earth sciences {2. Memorial University of Newfoundland St. Johns Canada

Dating of major sea-level changes using shells or calcareous microfossils is prone to errors in semi-enclosed marine environments where inputs of seawater and river water vary over time and space. The need to refine mollusc-based age estimates for the rate of the Holocene marine transgression in the Black Sea is the focus of multiple palaeoceanographic and archaeological studies. This ongoing “dating game” seeks to clarify conflicting evidence for a hypothetical catastrophic marine flood that forced the emigration of Neolithic farmers from the shores of a Holocene freshwater lake in the Black Sea. The potential importance of confirming or rejecting this megaflood hypothesis has led to multiple attempts at refining the chronology of the marine transgression and quantifying the palaeosalinity of the Black Sea surface water during the Holocene. Here we report that six new AmS radiocarbon ages of 8890 ± 50 to 8450 ± 40 yr Bp were obtained for wood, grass and sedge leaves from peat layers in Core 342.at 33.16 - 32.71 m below present sea level on the Ukrainian Shelf. These plant materials provide critical new ages for quantifying Black Sea carbon reservoir issues. The accuracy of our new AmS wood/peatages is independently supported by palynochronological correlation. The ages of our plant materials have ~100 years precisionandare ~42. - 52. years younger than those previously reported for unsorted detrital peat in Core 342. paired mollusc—wood ages for brackish—freshwater Dreissena polymorpha shell from detrital peat also shows that an inaccuracy of >112. yr can arise for shells during times when carbon reservoir values in the semi-isolated, brackish-water Black Sea could depart significantly from global average. Our revised sea level curve shows a gradual early Holocene transgression from water depths of -45.9 to -32.8 m, with initial mediterranean inflow by 8.9 ka Bp.

关键词： Radiocarbon Age Carbon Reservoir Delta peat Brackish molluscs palynology

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phase transitions between tropical,subtropical,and extratropical cyclones:A review from IWTC-10

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Tropical Cyclone Research and Review 2023年第4期12卷 294-308页

作者： Kimberly Wood Wataru Yanase jack Beven Suzana j.Camargo joseph B.Courtney Chris Fogarty junya Fukuda Naoko Kitabatake matthew Kucas Ron mcTaggart-Cowan michelle Simoes Reboita jacopo Riboldi The university of Arizona ArizonaUSA meteorological Research Institute IbarakiJapan National Hurricane Center MiamiUSA Lamont-Doherty earth Observatory Columbia UniversityPalisadesUSA Bureau of meteorology MelbourneAustralia Canadian Hurricane Center Nova ScotiaCanada japan meteorological Agency TokyoJapan meteorological College ChibaJapan joint Typhoon Warning Center HonoluluUSA Environment and Climate Change Gatineau QuebecCanada Federal university of Itajuba ItajubaBrazil ETH Zurich ZurichSwitzerland

This review,which was adapted from a Tenth International Workshop on Tropical Cyclones(IWTC-10)report,discusses research findings and operational practices relevant to cyclone types and phase transitions(extratropical,subtropical,and tropical).The cyclone phase space(CpS)method is widely used in both historical investigations and real-time evaluation of cyclone type and transition;however,CpS parameter values depend on input data resolution,and universal thresholds do not currently exist to delineate when a cyclone transitions from one type to *** of phase transitions in a changing climate highlight potential latitude shifts in extratropical transition and increased potential for tropical transition,but realistic projections of future trends likely require high-resolution simulations that can capture the cyclone warm *** meteorological centers apply varied approaches to cyclone classification via CpS parameters and other criteria,some of which depend on the tropical basin,yet these approaches cannot fully address challenges in operational classification and subsequently in communicating risks associated with these phase *** recommend a multivariate historical assessment of tropical and subtropical cyclones across all basins in which they occur,including the South Atlantic Ocean and the mediterranean Sea,to identify the potential for a more universal cyclone classification approach that meets operational needs.

关键词： Tropical cyclone Subtropical cyclone Extratropical transition Tropical transition

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Corrigendum to “Strategies towards robust interpretations of in situ zircon oxygen isotopes”[***.14(2.(2.2.)10152.]

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Geoscience Frontiers 2023年第6期14卷 496-496页

作者： janne Liebmann Christopher L.Kirkland john B.Cliff Christopher j.Spencer Aaron j.Cavosie Timescales of mineral Systems Group The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin UniversityPerthAustralia pacific Northwest National Laboratory RichlandWA 99354United States department of Geological sciences and Geological {2. Queen’s UniversityKingstonONCanada space science and Technology Centre The Institute for Geoscience Research(TIGeR)School of Earth and Planetary ScienceCurtin UniversityPerthAustralia

In the originally published version of our article(Liebmann et al.,2.2.),Table 2.incorrectly states that the publishedδ^(18)O value of reference zircon BR2.1 is 5.05‰±0.10‰.The correct value is 9.81‰±0.08‰(2.st... 详细信息

关键词： value zircon

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Quantification of radiation damage in natural and synthetic zircon by Raman spectroscopy:application to low-temperature thermochronology

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Acta Geochimica 2023年第4期42卷 673-688页

作者： Ke Su Shao-Bing Zhang john mHanchar Zhen-Xin Li Fang-Yuan Sun Ting Liang Xiao-Ying Gao CAS Key Laboratory of Crust-mantle materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Center of Excellence for Comparative planetology Chinese Academy of Sciences(CAS)Hefei 230026China Frontiers science Center for planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefei 230026China department of earth {2.s Memorial University of NewfoundlandSt John’sNL A1B 3X5Canada

Due to its ubiquitous occurrence in igneous,metamorphic,and sedimentary rocks and its wide application in geochronology and geochemistry,zircon has become the most widely used accessory mineral in the geological ***,the decay of U and Th causes radiation damage to the zircon structure,resulting in various degrees of metamictization,which can affect the accuracy of U–pb dates and Hf and O isotope *** the degree of zircon radiation damage can be quantified,the influence on geochemical analyses can be evaluated,and the results can be corrected more *** this paper,synthetic and natural zircon crystals with different crystallization ages were selected for Raman spectroscopy analysis,cathodoluminescence imaging,and determination of the U and Th *** results show that Raman FWHm(full width at half bandmaximum)and Raman shift correlate with alpha dose(Da)ofzirconsfollowingtheseequations,FWHm=44.36(±2.32.×[1-exp(-2.74×Da)]-+1.7(±0.19),Raman Shift=-6.53×Da+*** of synthetic zircon crystals shows that doped REEs(rare earth elements and p)can also lead to an increase in the ***,this effect can be ignored for natural zircon samples with REE contents at a normal level of hundreds to a few thousand *** FWHm and Raman shift can be used as proxies to measure the degree of zircon radiation *** the updated equations to calculate the latest age when zircon began to accumulate radiation damage,a more accurate and more meaningful“radiation damage age”can be obtained.

关键词： Zircon Radiation damage Raman spectroscopy FWHm(full width at half-maximum) Raman shift Raman isochron age

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