Water-bottom multiples from a dipping interface have the same kinematics in a Common Midpoint (CMP) gather as a primary from a reflector with twice the dip at twice the perpendicular depth at the CMP location. When migrated with the velocity of the primaries, these multiples are overmigrated just as primaries migrated with higher velocity, and their moveout is thus predictable in image space. D...

Before discussing multiplication, let us speak about addition. The number A(k) of distinct sums i+ j ≤ k such that 1 ≤ i ≤ k/2, 1 ≤ j ≤ k/2 is clearly 2 bk/2c − 1. Hence the number A(2n) of distinct elements in the n × n addition table involving {1, 2, . . . , n} satisfies limn→∞A(2n)/n = 2, as expected. We turn to multiplication. Let M(k) be the number of distinct products ij ≤ k such that 1 ≤...

Imaging of downgoing first-order free-surface multiples (ghosts) with VSP data can provide a subsurface image with wider coverage, better vertical resolution, and higher-fold than conventional imaging of VSP primary reflections. A problem with VSP downgoing first-order multiple (ghost) imaging is the interference from downgoing high-order multiples, similar to the interference from multiples wh...

I propose a new method to attenuate specularly-reflected multiples in the image space. The method is based on the difference in mapping between primaries and multiples in Subsurface Offset Domain Common Image Gathers (SODCIGs). I migrate the data with a velocity slower than that of the primaries but faster than that of the multiples. The primaries are therefore undermigrated whereas the multipl...

dans une conception traditionnelle, l’intelligence est fixée et peut être mesurée par un nombre dans un contexte déconnecté de toute réalité et s’attribuer une forme unique. dans une vision nouvelle, en se basant sur la théorie des intelligences multiples de gardner, l’intelligence a  en revanche de différentes composantes et peut être développée  durant toute la vie. le présent article s’intro...