IGU working group ‘landscape synthesis — geological foundations of complex landscape management.’ activities, 1984–85.     

Emil Mazur  Jan Drdoš 《GeoJournal》1986,12(1):121-121

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Variable stars in the globular cluster NGC 3201 – I. Multimode SX Phe type variables     

Beata Mazur  Wojciech Krzemi&#;ski  Ian B. Thompson ^&#; 《Monthly notices of the Royal Astronomical Society》2003,340(4):1205-1213

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The fall and recovery of the Tagish Lake meteorite     

Alan R. Hildebrand  Phil J. A. McCausland  Peter G. Brown  Fred J. Longstaffe  Sam D. J. Russell  Edward Tagliaferri  John F. Wacker  Michael J. Mazur 《Meteoritics & planetary science》2006,41(3):407-431

Abstract— The Tagish Lake C2 (ungrouped) carbonaceous chondrite fall of January 18, 2000, delivered ?10 kg of one of the most primitive and physically weak meteorites yet studied. In this paper, we report the detailed circumstances of the fall and the recovery of all documented Tagish Lake fragments from a strewnfield at least 16 km long and 3 to 4 km wide. Nearly 1 kg of “pristine” meteorites were collected one week after the fall before new snow covered the strewnfield; the majority of the recovered mass was collected during the spring melt. Ground eyewitnesses and a variety of instrument‐recorded observations of the Tagish Lake fireball provide a refined estimate of the fireball trajectory. From its calculated orbit and its similarity to the remotely sensed properties of the D‐ and P‐class asteroids, the Tagish Lake carbonaceous chondrite apparently represents these outer belt asteroids. The cosmogenic nuclide results and modeled production indicate a prefall radius of 2.1–2.4 m (corresponding to 60–90 tons) consistent with the observed fireball energy release. The bulk oxygen‐isotope compositions plot just below the terrestrial fractionation line (TFL), following a trend similar to the CM meteorite mixing line. The bulk density of the Tagish Lake material (1.64 ± 0.02 g/cm³) is the same, within uncertainty, as the total bulk densities of several C‐class and especially D‐ and P‐class asteroids. The high microporosity of Tagish Lake samples (?40%) provides an obvious candidate material for the composition of low bulk density primitive asteroids.  相似文献   

ACE Observations of the Bastille Day 2000 Interplanetary Disturbances     

Smith  C.W.  Ness  N.F.  Burlaga  L.F.  Skoug  R.M.  McComas  D.J.  Zurbuchen  T.H.  Gloeckler  G.  Haggerty  D.K.  Gold  R.E.  Desai  M.I.  Mason  G.M.  Mazur  J.E.  Dwyer  J.R.  Popecki  M.A.  Möbius  E.  Cohen  C.M.S.  Leske  R.A. 《Solar physics》2001,204(1-2):227-252

We present ACE observations for the six-day period encompassing the Bastille Day 2000 solar activity. A high level of transient activity at 1 AU, including ICME-driven shocks, magnetic clouds, shock-accelerated energetic particle populations, and solar energetic ions and electrons, are described. We present thermal ion composition signatures for ICMEs and magnetic clouds from which we derive electron temperatures at the source of the disturbances and we describe additional enhancements in some ion species that are clearly related to the transient source. We describe shock acceleration of 0.3–2.0 MeV nucl⁻¹ protons and minor ions and the relative inability of some of the shocks to accelerate significant energetic ion populations near 1 AU. We report the characteristics of < 20 MeV nucl⁻¹ solar energetic ions and < 0.32 MeV electrons and attempt to relate the release of energetic electrons to particular source regions.  相似文献   

Dispersion relation for ballooning modes and condition of their stability in the near-earth plasma     

N. G. Mazur  E. N. Fedorov  V. A. Pilipenko 《Geomagnetism and Aeronomy》2012,52(5):603-612

The ballooning disturbances in a finite-pressure plasma in a curvilinear magnetic field are described by a system of coupled equations for Alfvén and slow magnetosonic modes. The local dispersion relation obtained in a WKB approximation is the simplest and most evident method that can be used to characterize the properties of these disturbances. This dispersion relation is widely used to predict the possible instabilities and spectral properties of LF oscillations in the nightside magnetosphere. The formal derivation of the dispersion relation from the initial system of coupled MHD modes and the transition to different limiting cases have been traced. The behavior of dispersion curves in different oscillation branches and the possible development of instabilities and formation of regions where waves cannot propagate have been studied in detail. This made it possible to specify the results of previous works and even indicate the incorrectness in some works. In particular, it has been indicated that a fast Alfvén branch of oscillations is always stable and an aperiodic instability can originate on a slow magnetosonic oscillation branch.  相似文献   

Location of the Rheic suture in the eastern Bohemian Massif: evidence from detrital zircon data     

Stanisław Mazur  Jacek Szczepański  Krzysztof Turniak  Neal J. McNaughton 《地学学报》2012,24(3):199-206

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The origin of magnesite deposits from the Polish Foresudetic Block ophiolites: preliminary δ¹³C and δ¹⁸O investigations     

M. Orion Jedrysek  Stanislaw Halas 《地学学报》1990,2(2):154-159

Twenty-three magnesite samples from vein deposits, found in ultramafic rocks related to ophiolites in the north-east Bohemian Massif, have been examined for carbon and oxygen isotope ratios. In these rocks two stages of antigorite serpentinization took place prior to magnesite precipitation. δ¹⁸O_SMOW in magnesites ranges from 24.5 to 27.9%o (corrected for acid fractionation factor) which leads us to conclude a meteoric origin of the ore-forming solution. This inference is further supported by δ¹³C values (?18.7 to ?4.4%o) which point to a biogenic origin of carbon in the magnesites.  相似文献   

Tectonothermal history of the Holy Cross Mountains (Poland) in the light of low‐temperature thermochronology          下载免费PDF全文

Dariusz Botor  Aneta A. Anczkiewicz  István Dunkl  Jan Golonka  Mariusz Paszkowski  Stanisław Mazur 《地学学报》2018,30(4):270-278

The low‐temperature thermal history of the Holy Cross Mountains (HCM) is investigated by apatite fission track and apatite and zircon (U–Th)/He thermochronology. Our results provide constraints on the deformation history of Palaeozoic basement rocks in the transition area from Precambrian to Palaeozoic Europe that are exposed from beneath Permian–Mesozoic sediments within the HCM. Late to post‐Variscan cooling of the Palaeozoic strata from maximum temperatures is shown to be a major feature of the HCM. This cooling likely followed a heating event related to burial and/or hot fluid circulation along the Holy Cross Fault in the late Carboniferous. The central part of the HCM shows a rapid cooling event caused by tectonic inversion, which started in the Late Cretaceous. However, this event was less pronounced in the western margin of the HCM, where slow cooling continued throughout the Mesozoic with only minor acceleration of the cooling rate since the latest Cretaceous.  相似文献   

Alumovesuvianite,Ca19Al(Al,Mg)12Si18O69(OH)9, a new vesuvianite-group member from the Jeffrey mine,asbestos, Estrie region,Québec,Canada     

Panikorovskii  Taras L.  Chukanov  Nikita V.  Aksenov  Sergey M.  Mazur  Anton S.  Avdontseva  Evgenia Yu  Shilovskikh  Vladimir V.  Krivovichev  Sergey V. 《Mineralogy and Petrology》2017,111(6):833-842

Mineralogy and Petrology - Alumovesuvianite (IMA 2016–014), ideally Ca19Al(Al,Mg)12Si18O69(OH)9, is a new vesuvianite-group member found in the rodingite zone at the contact of a gabbroid...  相似文献   

Penetration to the Earth’s surface of standing Alfvén waves excited by external currents in the ionosphere     

A. S. Leonovich  V. A. Mazur 《Annales Geophysicae》1996,14(5):545-556

The problem of boundary conditions for monochromatic Alfvén waves, excited in the magnetosphere by external currents in the ionospheric E-layer, is solved analytically. Waves with large azimuthal wave numbers m≫1 are considered. In our calculations, we used a model for the horizontally homogeneous ionosphere with an arbitrary inclination of geomagnetic field lines and a realistic height disribution of Alfvén velocity and conductivity tensor components. A relationship between such Alfvén waves on the upper ionospheric boundary with electromagnetic oscillations on the ground was detected, and the spatial structure of these oscillations determined.  相似文献