The Late Neoproterozoic/Early Palaeozoic evolution of the West Congo Belt of NW Angola: geochronological (U‐Pb and Ar‐Ar) and petrostructural constraints     

Patrick Monié  Delphine Bosch  Olivier Bruguier  Alain Vauchez  Yann Rolland  Pedro Nsungani  André Buta Neto 《地学学报》2012,24(3):238-247

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The use of natural and archeological analogues for understanding the long-term behavior of nuclear glasses     

Guy Libourel  Aurelie Verney-Carron  Andreas Morlok  Stéphane Gin  Jérôme Sterpenich  Anne Michelin  Delphine Neff  Philippe Dillmann 《Comptes Rendus Geoscience》2011,343(2-3):237-245

The knowledge of the long-term behavior of nuclear waste in anticipation of ultimate disposal in a deep geological formation is of prime importance in a waste management strategy. If phenomenological models have been developed to predict the long-term behavior of these materials, validating these models remains a challenge, when considering the time scale of radioactive decay of radionuclides of environmental concern, typically 10⁴–10⁵ yrs. Here we show how natural or archaeological analogues provide critical constraints not only on the phenomenology of glass alteration and the mechanisms involved, but also on the ability of experimental short-term data to predict long-term alteration in complex environments.  相似文献   

Weak lensing by galaxies in groups and clusters – I. Theoretical expectations     

Xiaohu Yang  H. J. Mo  Frank C. van den Bosch  Y. P. Jing  Simone M. Weinmann  M. Meneghetti 《Monthly notices of the Royal Astronomical Society》2006,373(3):1159-1172

Three of the six southern Clube Areas that were mainly observed at the European Southern Observatory and whose principal results are given in Paper XVI are marginally observable from Haute-Provence. Additional measurements obtained on several observing runs there enabled orbits to be determined (in most cases rather poorly, owing to the paucity of data) for 30 of the newly discovered spectroscopic-binary systems; they are presented in this paper. One object, HD 33978, seems to be of such significance that special efforts have been made, largely by Drs J. Andersen and H. Lindgren, to obtain additional radial-velocity measurements. That system is shown to be a double-lined binary with a period of only 10.67 d despite one of its components being a late-type giant. The giant star has a projected rotational velocity of almost 40 km s⁻¹; it could be expected to exhibit RS CVn-type photometric variations, which have not yet been observed, in addition to the 'ellipsoidal variation', discovered by Hipparcos , which occasioned its designation as VV Lep.  相似文献   

Properties of galaxy groups in the Sloan Digital Sky Survey – II. Active galactic nucleus feedback and star formation truncation     

Simone M. Weinmann  Frank C. van den Bosch  Xiaohu Yang  H. J. Mo  Darren J. Croton  Ben Moore 《Monthly notices of the Royal Astronomical Society》2006,372(3):1161-1174

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Linking early- and late-type galaxies to their dark matter haloes     

Frank C. van den Bosch  Xiaohu Yang  H. J. Mo 《Monthly notices of the Royal Astronomical Society》2003,340(3):771-792

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Ruprecht 55: an OB association at the edge of our Galaxy     

Guillermo Bosch  †‡  Rodolfo Barbá  ‡§  Nidia Morrell  †‡§  Virpi Niemela  †‡¶  Pablo Ostrov  ‡  Marcelo Arnal  §  Cristina Cappa  §  Ricardo Morras §  Guillermo Giménez de Castro 《Monthly notices of the Royal Astronomical Society》2003,341(1):169-178

We present new spectroscopy in the optical range and 21-cm H  i data covering the Ruprecht 55 (Ru 55) field in the Puppis window where several authors have proposed the existence of one (or two) clusters.
We have determined new MK spectral types for about 50 stars in the region, finding 43 OB-type stars among them. LS 985 was found to be an O9 V + O9.5 III binary and it is the earliest type of star in our observed sample.
We have identified a stellar OB association (Ru 55), which is most likely related to a depletion detected in our H  i data, as: (i) they are located at the same distance (6 kpc), within observational errors; (ii) both have similar radial velocities (∼67 km s⁻¹); (iii) current OB stars could have provided the energy needed to blow the cavity; (iv) the dynamical time-scale for the hole buildup matches the age estimated for the earliest OB stars; and (v) LS 985 might be responsible for ionizing the H  i cavity inner walls close to it.  相似文献   

Two new evolved bipolar planetary nebulae in the solar neighbourhood     

David J. Frew †  Quentin A. Parker  Delphine Russeil 《Monthly notices of the Royal Astronomical Society》2006,372(3):1081-1092

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The contrasting geochemical message from the New Caledonia gabbronorites: insights on depletion and contamination processes of the sub-arc mantle in a nascent arc setting     

Arianna?Secchiari  Alessandra?MontaniniEmail author  Delphine?Bosch  Patrizia?Macera  Dominique?Cluzel 《Contributions to Mineralogy and Petrology》2018,173(8):66

The New Caledonia ophiolite hosts one of the rare examples of crust-mantle sections built in a nascent arc environment, providing the unique opportunity to investigate the first stages of arc magmatism in a subduction setting. The sequence consists of refractory harzburgites, overlain by ultramafic (dunites and wehrlites) and mafic lithologies (gabbronorites). The gabbronorites occur in the upper part of the sequence as decimetre to metre-size sills. They are mainly formed (??55 to 70 vol%) of Ca-rich plagioclase (An up to 96 mol%) and high Mg# (88–92), Al₂O₃-poor (1.5–2.4 wt%) clinopyroxene (8–20 vol%), often rimmed by interstitial or poikilitic orthopyroxene (6–27 vol%). Mg-rich olivine (3–15 vol%, Fo?=?87–89 mol%) occurs as anhedral, resorbed crystals. Whole rock (WR) compositions exhibit high Mg# (86–92) and strikingly low trace element contents. They own LREE-depleted patterns, with nearly flat (0.82?≤?Dy_N/Yb_N?≤?1.00) and low HREE (Yb_N?=?0.2–0.9) and positive Eu anomalies. Clinopyroxene trace element chemistry mirrors the extreme depletion of the WR. By contrast, FME enrichments are observed for WR and clinopyroxene. Geochemical models show that the gabbronorites crystallized from primitive, ultra-depleted melts bearing evidence of fluid contamination processes, but with significantly different geochemical signatures compared to boninitic rocks worldwide, i.e. lower LREE-MREE, and absence of Nb depletion and Zr–Hf enrichments. Nd isotopes (+?8.2?≤?εNd_i?≤?+?13.1), together with radiogenic Pb isotopic ratios, support an origin from a DMM source variably modified by slab fluids. We propose that the geochemical signature of the New Caledonia gabbronorites reflect emplacement of primitive, non-aggregated, magma batches in the lower fore-arc crust, during the first phases of arc formation.  相似文献   

Hazard and risk intensity maps for water-bearing units: a case study     

D. F. Hamamin  R. A. Qadir  S. S. Ali  A. P. Bosch 《International Journal of Environmental Science and Technology》2018,15(1):173-184

Fresh groundwater from intergranular and carbonate aquifers are considered as the valuable resources for domestic, agricultural and industrial water supplies of the Iraqi Kurdistan Region. A comprehensive approach to groundwater protection using the intrinsic vulnerability, hazard and risk intensity mapping was proposed by the European COST Action 620. The current article applied all the components of the above mentioned Pan-European approach to assess the risk harmfulness in the Sulaimani sub-basin by combining hydrogeological parameters using the DRASTIC system and the hazard components by taking the product of the weighted hazard value (H_I), the ranking factor (Q_n) and the reduction factor (R_f). The hazard map was constructed from twenty-six hazard feature types of the point, line and polygon. Their distributions, extents and of harmfulness degrees vary sharply from one place to another. Results of the risk intensity map divided the area into five classes as “no or very low, low, moderate, high and very high” risk zones. Fortunately, the majority of the area of interest is classified as very low to low contamination potential due to the limited impact of hazards as well as low groundwater vulnerabilities. The zones with moderate-risk potentials clustered in industrialized areas.  相似文献   

Potential of SARAL/AltiKa for Inland Water Applications     

Christian Schwatke  Denise Dettmering  Eva Börgens  Wolfgang Bosch 《Marine Geodesy》2015,38(3):626-643

SARAL uses the same orbit as ERS and Envisat and can be used to extend inland water height time series derived from these missions. This article investigates the potential of SARAL for this application over the Great Lakes and the Amazon basin. SARAL/AltiKa is the first altimeter using Ka-band that is rarely influenced by ionospheric effects but susceptible for atmospheric water. Our investigations show clear waveform disruptions for SARAL due to precipitation. It is demonstrated that the quality of water heights improved when using alternative retracker products, for example, the ice-1 product. The improvement depends on the weather and yields up to 3.8 cm for wet conditions. The advantage of the smaller footprint of SARAL is demonstrated for land-water transitions where SARAL provides better water level heights up to 6 km to the lakeshore whereas Envisat is limited to about 11 km. SARAL provides also more reliable water level heights for narrow Amazon rivers than Envisat. Furthermore, the hooking effect is decreased for SARAL. Comparing water level time series of SARAL-only, Envisat-only, and multi-mission with in-situ data demonstrates that SARAL has the potential to extend Envisat long-term time series and to decrease the RMS by about 10% for large lakes and 40% for selected rivers.  相似文献