Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Acta Geophysica

1 2020

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Q-compensation

Sortuj według:

Ogranicz wyniki do:

Multi-trace nonstationary sparse inversion with structural constraints

Cheng Liang, Wang Shangxu, Li Shengjun, Ji Yongzhen

Acta Geophysica

2020

Vol. 68, no. 3

675--685

The recorded seismic signals are attenuated and spatially correlated due to their propagation through an elastic earth and the sedimentary rule of strata. This attenuation phenomenon is quantifed by means of the earth quality factor (Q) or the attenuation factor (1∕Q). Nowadays, the related Q-compensation and multi-trace inversion for the seismic data are two challenging problems when used for enhancing the temporal resolution and preserving the spatial continuity. Separately estimating Q and refectivity are difcult and produce the uncertainty or ill-condition problems. To overcome these limitations, we have developed a multi-trace nonstationary sparse inversion with structural constraint. Using prior dipping-angle information and refectivity sparsity property, the proposed method simultaneously estimates equivalent-Q and refectivity with structural constraint. Constructed by the source wavelet and diferent scanned equivalent-Q, a series of time-varying (nonstationary) wavelet matrices are provided for the forward-modeling schemes and the corresponding inversions. When the Q-model is infnitely close to the true attenuation mechanism, the corresponding inverted refectivity is comparatively sparse and quantifed as maximum sparsity or minimum sparse representation. A sparse representation function, such as l0.1-norm, is used for sparsity measurement of the inverted refectivity corresponding to each scanned Q. Through optimizing these sparse representation values, a suitable equivalent-Q, as well as the corresponding inverted refectivity with structural preservation and Q-attenuation, is determined. The synthetic and feld examples both confrmed a substantial improvement on seismic records, especially for Q-estimation, structure preservation and Q-compensation.