Gravitomagnetic corrections to the lensing deflection angle for spiral galaxy models     

S. Capozziello  V. F. Cardone  V. Re  M. Sereno 《Monthly notices of the Royal Astronomical Society》2003,343(2):360-366

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PIANCALDOLI METEORITE: CHEMISTRY,MINERALOGY AND PETROLOGY     

Marcello Carapezza  P. Mario Nuccio  Mariano Valenza 《Meteoritics & planetary science》1976,11(3):195-205

The fall occurred near Piancaldoli, Florence, Italy, at 19.14 U.T. on the 10th August 1968. The fireball broke up in the atmosphere producing a cloud like a balloon. The trajectory and the terminal point were calculated, leading to the recovery of three small meteoritic fragments, found on the roof of a house. Chemical analysis gave the following results: SiO₂ 40.80; TiO₂ 0.15; Al₂O₃ 2. 70; Cr₂O₃ 0.47; FeO 17.20; MnO 0.07; MgO 25.18; CaO 1.95; Na₂O 0.64; K₂O 0.07; P₂O₅ 0.20; NiS 0.93; FeS 6.24; Fe° 2.40; Ni° 0.40; Co 0.05; sum 99.45. In the lithic portion of the meteorite the following minerals were found: both clino and orthopyroxenes (En = 76 to 98%), olivines (Fo = 66 to 98%), troilite, pyrrhotite, pentlandite, kamacite, ilmenite, apatite, merillite, schreibersite, chromite and Henderson phase. From all the mineralogical and petrological data, we conclude that the Piancaldoli meteorite is an “unequilibrated ordinary chondrite,” LL3. The microbrecciated structure of the rock and some shock features were observed, while the rock as a whole is unshocked, suggesting that these features were caused by impact events which took place during the accretion of the parent body.  相似文献   

Hyaloclastites and pillow lavas of Acicastello (Mt. Etna)     

Maria Di Re 《Bulletin of Volcanology》1963,25(1):281-284

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Why do we see the man in the Moon?     

Oded Aharonson  Peter Goldreich  Re’em Sari 《Icarus》2012,219(1):241-243

Numerical simulations and analysis show that the Moon locks into resonance with a statistical preference of facing either the current near-side or far-side toward Earth. The near-side is largely covered by dense, topographically low, dark mare basalts, the pattern of which to some, resembles the image of a man’s face. Although the Moon is locked in this configuration at present, the opposite one, with the current far-side facing Earth, is of lower potential energy and hence might be naively expected. Instead, we find that the probability of selecting each configuration depends upon the ratio of the asymmetry of the potential energy maxima, dominated by the octupole moment of the Moon, to the energy dissipated per tidal cycle within the Moon. If this ratio is small, the two configurations are equally likely. Otherwise, interesting dynamical behavior ensues. In the Moon’s present orbit, with the best-estimated geophysical parameters and dissipation parameter Q = 35, trapping into the current higher-energy configuration is preferred. With Q = 100 in analogy with the solid Earth, the current configuration is nearly certain. The ratio of energies and corresponding probabilities were different in the past. Relative crater counts on the leading and trailing faces indicate an impact may have unlocked the Moon before it settled into the present configuration. Our analysis constrains the geophysical parameters at the time of the last such event.  相似文献   

Uptake of hazardous elements by spring onion (<Emphasis Type="Italic">Allium fistulosum</Emphasis> L.) from soil irrigated with different types of water and possible health risk     

Kafeel Ahmad  Zafar Iqbal Khan  Asma Ashfaq  Muhammad Ashraf  Nudrat Aisha Akram  Muhammad Sher  Hazoor Ahmad Shad  Vincenzo Tufarelli  Antonio Lonigro  Mariano Fracchiolla  Eugenio Cazzato 《Environmental Earth Sciences》2017,76(8):322

Bio-concentration of elements such as Mo, As, Se, Fe, Cu, Zn, Ni and Pb was analyzed in spring onion (Allium fistulosum L.) in three different locations of central Punjab, Pakistan. At location GW, relatively low level of hazardous elements was found in spring onion, suggesting that groundwater is a safe source of water for irrigating food crops. The pH of soil at wastewater irrigation was found less acidic (pH 7.4) than the other sites. The range of concentration in the different samples of spring onion was as follows: 6.15–8.16 mg kg^?1 for Mo, 2.77–4.28 mg kg^?1 for As, 0.395–0.705 mg kg^?1 for Se, 36.73–48.17 mg kg^?1 for Fe, 10.58–16.26 mg kg^?1 for Cu, 28.87–39.79 mg kg^?1 for Zn, 6.66–8.75 mg kg^?1 for Ni and 4.33–6.09 mg kg^?1 for Pb, respectively. High bio-concentration of Zn (15.37) from soil to spring onion was found at canal water irrigated location. The estimated daily intake of metal for spring onion was less, but the health risk index was higher than 1 for Mo, As, Cu, Pb and Ni, respectively. This was due to higher proportion of spring onion in diet, which consequently increased the health risk index for metals. Therefore, it is recommended to avoid growing vegetables in untreated urban and rural wastewater containing elevated amounts of metals.  相似文献   

Fluvial architecture as a response to two-layer lithospheric subsidence during the Permian and Triassic in the Iberian Basin,eastern Spain     

José López-Gómez  Alfredo Arche  Henar Vargas  Mariano Marzo 《Sedimentary Geology》2010,223(3-4):320-333

The stratigraphy of a sedimentary basin is mainly the result of the long-term response of a depositional surface to prolonged subsidence. However, the real nature of interrelations between fluvial architecture and subsidence is still unknown. Herein, we present new data on these relationships by combining the results of detailed sedimentological field work with data acquired through automated forward modelling and backstripping for the alluvial Permian and Triassic sediments of the SE Iberian Ranges. Using this methodology, we determined tectonic subsidence of the basin by means of backstripping analysis and crust and lithospheric mantle stretching factors (δ and β, respectively) using forward modelling technique. Results indicated that a configuration of two individual and independent layers during lithospheric subsidence for each tectonic phase fit better for this time of the studied basin evolution than the assumption of subsidence due to a single layer spanning the whole lithosphere.For this study, we simplified fluvial geometries as two main types: isolated (I) and amalgamated (A), with subtypes in each case. Different order bounding surfaces (b.s.) were distinguished in the field, although we only selected those affecting the whole basin under study. These included those b.s. of clear tectonic origin, ranging from individual basin boundary-fault pulses produced over periods of approximately 1 My to those arising from major tectonic events, such as the beginning of extension in the basin, causing major changes in basin geometry over periods of 3–5 My.The comparison of δ and β values and fluvial geometries for each identified tectonic phase in the basin evolution, revealed some possible relationship between subsidence and fluvial geometry: Sections showing the most varied fluvial architectural geometries, including ribbon and nested forms, were related to higher β and δ stretching factors values indicating tectonic phases of greater stretching and subsidence. When both stretching factors were similar and close to 1, fluvial geometry was basically reduced to amalgamated geometry type. Wider ranging of fluvial geometries was associated with stages of basin development in which crust and upper mantle activities differed, that is, showing larger differences of β and δ stretching factors values. The related slope changes are proposed as the main surface control of fluvial styles.Combination of subsidence with other possible controlling factors such as avulsion rate, climate or budget of sediments, gives rise to the definitive alluvial architecture of a basin.  相似文献   

An investigation of cathodoluminescence in albite from the A-type Georgeville granite,Nova Scotia     

Kim N. Dalby  Alan J. Anderson  Anthony N. Mariano  Robert A. Gordon  Robert A. Mayanovic  Richard Wirth 《Lithos》2010,114(1-2):86-94

Cathodoluminescence (CL) reveals red and blue colors within single, non-turbid albite (Ab_98–99) grains from the Georgeville granite, Nova Scotia. A 720 nm X-ray excited optical luminescence (XEOL) peak characterizes red CL regions, while a 280 nm XEOL feature dominates blue CL regions. Synchrotron X-ray fluorescence results indicate that red CL and the 720 nm XEOL peak intensities relate to total Fe concentrations. The relationship between red CL and Fe content is confirmed by electron microprobe (EMPA) and laser ablation-inductively coupled mass spectrometry (LA-ICP-MS). The XEOL technique is used to exclude the Fe K-edge as the cause of red CL. X-ray absorption spectroscopy results indicate that Fe in both the red and blue CL regions is Fe³⁺, and that red CL activation may relate to the Si–Al order of the feldspar and to the distribution of Fe on tetrahedral sites. The CL textures, combined with EMPA and LA-ICPMS analyses, indicate that blue CL albite (Ab₉₈) regions contain higher concentrations of Ca, Ti, Pb and rare earth elements, and were replaced, in part, by a more Fe-rich, trace element depleted albite (Ab₉₉) which displays red CL. Complex diffraction contrasts and amorphous deposits identified in transmission electron microscope images suggest that aqueous fluids have reacted with both red and blue CL regions. Fluid inclusion homogenization temperatures of up to 430 °C provide a lower estimate of the fluid temperature.  相似文献   

Moisture source in the Hyblean Mountains region (south-eastern Sicily, Italy): Evidence from stable isotopes signature     

Fausto Grassa  Rocco Favara  Mariano Valenza 《Applied Geochemistry》2006,21(12):2082-2095

Here the authors present results of an isotope study on precipitation collected during a 2-a period from a rain-gauge network consisting of 6 stations located at different elevations in the Hyblean Mountains (HM) region, in south-eastern Sicily. The slope of the local meteoric water line (δD = 6.50 δ¹⁸O + 9.87) obtained for the region suggests that precipitation is affected by evaporation during rainfall events. The main variations in rainwater isotope composition are due to seasonal effects and elevation. An average ²H excess value of +21.2‰ was found for precipitation events less affected by evaporation (i.e. when the rainfall was >65 mm/month). The spatial distribution of O isotope composition of precipitation shows a negative gradient from east and south to the inner areas. The depositional rate of Cl, used as a tracer of the origin of air masses, is highest at the coastal rain-gauges (SR and MRG stations) and lowest on the northern flank of the HM region (SC station). Based on these findings, a model is proposed for the origin of precipitation in the HM region, which assumes that a Mediterranean-derived component is the main source of moisture in the studied area. D/H and ¹⁸O/¹⁶O ratios of inferred meteoric recharge waters were also compared with the isotope composition of waters collected from the main local springs and wells. The best linear fit of the δ¹⁸O vs δD relationship for Hyblean groundwater is δD = 4.85 δ¹⁸O–2.01. The enrichment of heavy isotopes in Hyblean groundwater is probably due to evaporation occurring after precipitation events or to a recharging contribution from surface waters (lakes or rivers) enriched in heavy isotopes.  相似文献   

Fault-controlled Soil CO2 Degassing and Shallow Magma Bodies: Summit and Lower East Rift of Kilauea Volcano (Hawaii), 1997     

Salvatore Giammanco  Sergio Gurrieri  Mariano Valenza 《Pure and Applied Geophysics》2006,163(4):853-867

Soil CO₂ flux measurements were carried out along traverses across mapped faults and eruptive fissures on the summit and the lower East Rift Zone of Kilauea volcano. Anomalous levels of soil degassing were found for 44 of the tectonic structures and 47 of the eruptive fissures intercepted by the surveyed profiles. This result contrasts with what was recently observed on Mt. Etna, where most of the surveyed faults were associated with anomalous soil degassing. The difference is probably related to the differences in the state of activity at the time when soil gas measurements were made: Kilauea was erupting, whereas Mt. Etna was quiescent although in a pre-eruptive stage. Unlike Mt. Etna, flank degassing on Kilauea is restricted to the tectonic and volcanic structures directly connected to the magma reservoir feeding the ongoing East Rift eruption or in areas of the Lower East Rift where other shallow, likely independent reservoirs are postulated. Anomalous soil degassing was also found in areas without surface evidence of faults, thus suggesting the possibility of previously unknown structures. Received: November 2003, revised: January 2005, accepted: January 2005  相似文献   

Reply to comments by G. Gambolati and G. Galeati     

Shlomo P. Neuman  Javier Samper  Mariano Hernandez 《Mathematical Geology》1987,19(3):259-266

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