scholarly journals Development of a Density Inversion in Driven Granular Gases

2003 ◽  
pp. 251-266 ◽  
Author(s):  
Yaron Bromberg ◽  
Eli Livne ◽  
Baruch Meerson
Keyword(s):  
Granular Gases ◽  
Density Inversion

Experimental determination of a state equation for dissipative granular gases

1999 ◽  
Vol 96 (6) ◽  
pp. 1111-1116 ◽  
Author(s):  
E. Falcon ◽  
S. Fauve ◽  
C. Laroche
Keyword(s):  
Experimental Determination ◽  
State Equation ◽  
Granular Gases

Magmatic and tectonic emplacement of the Pukaskwa batholith, Superior Province, Ontario, CanadaThis article is one of a series of papers published in this Special Issue on the theme of Geochronology in honour of Tom Krogh.

2011 ◽  
Vol 48 (2) ◽  
pp. 187-204 ◽  
Author(s):  
Gary P. Beakhouse ◽  
Shoufa Lin ◽  
Sandra L. Kamo
Keyword(s):  
Partial Melting ◽  
Abrupt Change ◽  
Superior Province ◽  
Density Inversion ◽  
Tectonic Processes ◽  
Slab Breakoff ◽  
Greenstone Belts ◽  
Lower Crustal ◽  
Basaltic Crust ◽  
Structural Dome

The Neoarchean Pukaskwa batholith consists of pre-, syn-, and post-tectonic phases emplaced over an interval of 50 million years. Pre-tectonic phases are broadly synvolcanic and have a high-Al tonalite–trondhjemite–granodiorite (TTG) affinity interpreted to reflect derivation by partial melting of basaltic crust at lower crustal or upper mantle depths. Minor syn-tectonic phases slightly post-date volcanism and have geochemical characteristics suggesting some involvement or interaction with an ultramafic (mantle) source component. Magmatic emplacement of pre- and syn-tectonic phases occurred in the midcrust at paleopressures of 550–600 MPa and these components of the batholith are thought to be representative of the midcrust underlying greenstone belts during their development. Subsequent to emplacement of the syntectonic phases, and likely at approximately 2680 Ma, the Pukaskwa batholith was uplifted as a structural dome relative to flanking greenstone belts synchronously with ongoing regional sinistral transpressive deformation. The driving force for vertical tectonism is interpreted to be density inversion (Rayleigh–Taylor-type instabilities) involving denser greenstone belts and underlying felsic plutonic crust. The trigger for initiation of this process is interpreted to be an abrupt change in the rheology of the midcrust attributed to introduction of heat from the mantle attendant with slab breakoff or lithospheric delamination following the cessation of subduction. This process also led to partial melting of the intermediate to felsic midcrust generating post-tectonic granitic phases at approximately 2667 Ma. We propose that late density inversion-driven vertical tectonics is an inevitable consequence of horizontal (plate) tectonic processes associated with greenstone belt development within the Superior Province.

scholarly journals Self-diffusion in freely evolving granular gases

2000 ◽  
Vol 12 (4) ◽  
pp. 876-883 ◽  
Author(s):  
J. Javier Brey ◽  
M. J. Ruiz-Montero ◽  
D. Cubero ◽  
R. Garcı́a-Rojo
Keyword(s):  
Granular Gases ◽  
Self Diffusion

scholarly journals Thermal Convection in Granular Gases with Dissipative Lateral Walls

2016 ◽  
Vol 117 (9) ◽  
Author(s):  
Giorgio Pontuale ◽  
Andrea Gnoli ◽  
Francisco Vega Reyes ◽  
Andrea Puglisi
Keyword(s):  
Thermal Convection ◽  
Granular Gases ◽  
Lateral Walls

scholarly journals Longitudinal Viscous Flow in Granular Gases

2008 ◽  
Author(s):  
Andrés Santos ◽  
Takashi Abe
Keyword(s):  
Viscous Flow ◽  
Granular Gases

scholarly journals A universal scaling law for the evolution of granular gases

2016 ◽  
Vol 114 (1) ◽  
pp. 10002 ◽  
Author(s):  
Mathias Hummel ◽  
James P. D. Clewett ◽  
Marco G. Mazza
Keyword(s):  
Scaling Law ◽  
Granular Gases ◽  
Universal Scaling

scholarly journals Self-diffusion in granular gases: Green–Kubo versus Chapman–Enskog

2005 ◽  
Vol 15 (2) ◽  
pp. 026108 ◽  
Author(s):  
Nikolai V. Brilliantov ◽  
Thorsten Pöschel
Keyword(s):  
Granular Gases ◽  
Self Diffusion

Highly efficient density inversion of gravity data using nonlinear density polynomial fitting

Geophysics ◽  
2021 ◽  
pp. 1-34
Author(s):  
Guoqing Ma ◽  
Zongrui Li ◽  
Lili Li ◽  
Taihan Wang
Keyword(s):  
Weighting Function ◽  
Gravity Data ◽  
Real Life ◽  
Density Variation ◽  
Density Change ◽  
Inversion Method ◽  
Density Inversion ◽  
Perspective View ◽  
Polynomial Fitting ◽  
Polynomial Coefficients

The density inversion of gravity data is commonly achieved by discretizing the subsurface into prismatic cells and calculating the density of each cell. During this process, a weighting function is introduced to the iterative computation to reduce the skin effect during the inversion. Thus, the computation process requires a significant number of matrix operations, which results in low computational efficiency. We have adopted a density inversion method with nonlinear polynomial fitting (NPF) that uses a polynomial to represent the density variation of prismatic cells in a certain space. The computation of each cell is substituted by the computation of the nonlinear polynomial coefficients. Consequently, the efficiency of the inversion is significantly improved because the number of nonlinear polynomial coefficients is less than the number of cells used. Moreover, because representing the density change of all of the cells poses a significant challenge when the cell number is large, we adopt the use of a polynomial to represent the density change of a subregion with fewer cells and multiple nonlinear polynomials to represent the density changes of all prism cells. Using theoretical model tests, we determine that the NPF method more efficiently recovers the density distribution of gravity data compared with conventional density inversion methods. In addition, the density variation of a subregion with 8 × 8 × 8 prismatic cells can be accurately and efficiently obtained using our cubic NPF method, which can also be used for noisy data. Finally, the NPF method was applied to real gravity data in an iron mining area in Shandong Province, China. Convergent results of a 3D perspective view and the distribution of the iron ore bodies were acquired using this method, demonstrating the real-life applicability of this method.

NUMERICAL SIMULATION OF NATURAL CONVECTION WITH DENSITY INVERSION IN A SQUARE CAVITY

2000 ◽  
Vol 37 (4) ◽  
pp. 395-406 ◽  
Author(s):  
Masaaki Ishikawa, Tetsuo Hirata, Sh
Keyword(s):  
Numerical Simulation ◽  
Natural Convection ◽  
Density Inversion ◽  
Square Cavity

scholarly journals NeXtYZ: Three-dimensional electron density inversion for dynasonde ionograms

Radio Science ◽  
2006 ◽  
Vol 41 (6) ◽  
pp. n/a-n/a ◽  
Author(s):  
N. A. Zabotin ◽  
J. W. Wright ◽  
G. A. Zhbankov
Keyword(s):  
Electron Density ◽  
Three Dimensional ◽  
Density Inversion ◽  
Dimensional Electron
Sign in / Sign up

Export Citation Format

Share Document