Submarine-fan facies associations of the Upper Cretaceous and Paleocene Gottero Sandstone, Ligurian Apennines, Italy     

Tor H. Nilsen  Ernesto Abbate 《Geo-Marine Letters》1984,3(2-4):193-197

The Upper Cretaceous and Paleocene Gottero Sandstone was deposited as a small deep-sea fan on ophiolitic crust in a trench-slope basin. It was thrust northeastward as an allochthonous sheet in Early and Middle Cenozoic time. The Gottero, as thick as 1500 m, was probably derived from erosion of Hercynian granites and associated metamorphic rocks in northern Corsica. Outcrops of inner-fan channel, middle-fan channel and interchannel, outer-fan lobe, fan-fringe, and basin-plain facies associations indicate that the depositional model of Mutti and Ricci Lucchi for mixed-sediment deep-sea fans can be used. The original fan had a radius of 30 to 50 km. Margin setting represents fan and/or source area  相似文献   

Time scaling as an infinitesimal canonical transformation     

José F. Cariñena  Luis A. Ibort  Ernesto A. Lacomba 《Celestial Mechanics and Dynamical Astronomy》1987,42(1-4):201-213

We show that time scaling transformations for Hamiltonian systems are infinitesimal canonical transformations in a suitable extended phase space constructed from geometrical considerations. We compute its infinitesimal generating function in some examples: regularization and blow up in celestial mechanics, classical mechanical systems with homogeneous potentials and Scheifele theory of satellite motion.Research partially supported by CONACYT (México), Grant PCCBBNA 022553 and CICYT (Spain).  相似文献   

Application of Non-linear Analysis to Intensity Oscillations of the Chromospheric Bright Points     

Joydeep Bhattacharya  Ernesto Pereda  Rangaiah Kariyappa  Partha Pratim Kanjilal 《Solar physics》2001,199(2):267-290

We have applied several nonlinear techniques to the intensity oscillations of the chromospheric bright points observed at the Vacuum Tower Telescope (VTT) of the Sacramento Peak Observatory. A 35-min time sequence obtained in the Caii H line over a quiet region at the center of the solar disk under high spatial, spectral, and temporal resolution has been used. A relatively new approach is used to detect the hidden periodicity and to extract the associated periodic component(s) from an apparently irregular time series. The unique feature of this approach is that the constituent component(s) can be non-sinusoidal in nature. The periodicity analysis shows that time series of intensity oscillations of most of the bright points can be composed of two non-sinusoidal periodic components with periodicity varying between 2.4 min and 5.8 min. With the help of a multivariate embedding technique, globally significant spatial nonlinear correlation is found. The identification of the nonlinear interaction between bright points is performed by using the methods of dynamical phase synchronization and the similarity index. The analysis indicates that bright points are interconnected in the sense that some bright points are more active and can influence the other relatively passive bright points.  相似文献   

Physically based evaluation of climate models over the Iberian Peninsula     

Carmen Sánchez de Cos  Jose M. Sánchez-Laulhé  Carlos Jiménez-Alonso  Juan M. Sancho-Avila  Ernesto Rodriguez-Camino 《Climate Dynamics》2013,40(7-8):1969-1984

A novel approach is proposed for evaluating regional climate models based on the comparison of empirical relationships among model outcome variables. The approach is actually a quantitative adaptation of the method for evaluating global climate models proposed by Betts (Bull Am Meteorol Soc 85:1673–1688, 2004). Three selected relationships among different magnitudes involved in water and energy land surface budgets are firstly established using daily re-analysis data. The selected relationships are obtained for an area encompassing two river basins in the southern Iberian Peninsula corresponding to 2 months, representative of dry and wet seasons. The same corresponding relations are also computed for each of the thirteen regional simulations of the ENSEMBLES project over the same area. The usage of a metric based on the Hellinger coefficient allows a quantitative estimation of how well models are performing in simulating the relations among surface magnitudes. Finally, a series of six rankings of the thirteen regional climate models participating in the ENSEMBLES project is obtained based on their ability to simulate such surface processes.  相似文献   

Structure and modeling of disorder in miserite from the Murun (Russia) and Dara-i-Pioz (Tajikistan) massifs     

Ekaterina Kaneva  Maria Lacalamita  Ernesto Mesto  Emanuela Schingaro  Fernando Scordari  Nikolay Vladykin 《Physics and Chemistry of Minerals》2014,41(1):49-63

The structure, structural disorder and chemistry of miserite from the charoite-bearing rocks of the Murun massif (Russia) and from alkaline-syenite pegmatitic rocks of the Dara-i-Pioz massif (Tajikistan) were investigated employing a combination of electron microprobe, single crystal diffraction and micro-Fourier transform infrared spectroscopy analysis. Chemical analysis of the sample investigated by X-ray diffraction evidenced that Dara-i-Pioz miserite has a greater REE concentration than Murun miserite (~0.22 vs. 0.05 apfu, respectively) and also contains Y (0.14 apfu), which is absent in Murun miserite. The occurrence of a band at about 1,600 cm^?1 testified to the presence of H₂O in miserite at hand. Structural analyses yielded average cell parameters of a = 10.092, b = 16.016, c = 7.356 Å, α = 96.60°, β = 111.27° and γ = 76.34°. Anisotropic structural refinement in space group P $\bar{1}$ converged at similar values for the analyzed samples (R ~3.4, R _w ~3.8 %). An interesting feature shown by both the miserite specimen is the presence, revealed by difference Fourier analysis, of a disordered part of the structure. This turned out to be due to the flipping of the tetrahedra belonging to the isolated [Si₂O₇]^6? diorthogroups, one of the two radicals (the other is [Si₁₂O₃₀]^12?) characterizing the miserite structure. The sixfold and seven-vertex Ca polyhedra linked to the inverted diorthogroups show variation in coordination number with respect to those of the ordered structure.  相似文献   

A Functional Data Analysis Approach to Surrogate Modeling in Reservoir and Geomechanics Uncertainty Quantification     

Francesca Bottazzi  Ernesto Della Rossa 《Mathematical Geosciences》2017,49(4):517-540

Uncertainty quantification for geomechanical and reservoir predictions is in general a computationally intensive problem, especially if a direct Monte Carlo approach with large numbers of full-physics simulations is used. A common solution to this problem, well-known for the fluid flow simulations, is the adoption of surrogate modeling approximating the physical behavior with respect to variations in uncertain parameters. The objective of this work is the quantification of such uncertainty both within geomechanical predictions and fluid-flow predictions using a specific surrogate modeling technique, which is based on a functional approach. The methodology realizes an approximation of full-physics simulated outputs that are varying in time and space when uncertainty parameters are changed, particularly important for the prediction of uncertainty in vertical displacement resulting from geomechanical modeling. The developed methodology has been applied both to a subsidence uncertainty quantification example and to a real reservoir forecast risk assessment. The surrogate quality obtained with these applications confirms that the proposed method makes it possible to perform reliable time–space varying dependent risk assessment with a low computational cost, provided the uncertainty space is low-dimensional.  相似文献