TY - GEN

T1 - Reflection FWI in MBTT formulation

T2 - 7th EAGE Saint Petersburg International Conference and Exhibition: Understanding the Harmony of the Earth's Resources Through Integration of Geosciences

AU - Tcheverda, V.

AU - Gadylshin, K.

AU - Chavent, G.

AU - Shin, C.

AU - Shin, J.

PY - 2016

Y1 - 2016

N2 - Unfortunately we have to admit that after decades of development there are still no reliable techniques of full waveform inversion which guarantee reliable reconstruction of both macrovelocity model and reflectors reconstruction for reasonable acquisitions and frequency ranges. As reasonable we mean realistic offsets (about one-two depths of target objects) and temporal frequency above 5-7 Hz. The paper is devoted to the so-called Migration Based Travel Times (MBTT) formulation of the data misfit functional. This approach relies on the decomposition of a velocity model onto two subspaces - smooth propagator and rough depth reflectors. On this base the modified data misfit functional is introduced and compared with standard least squares formulation. Numerical Singular Value Decomposition proves that these two formulations produce functionals which have almost orthogonal stable subspaces. As is well known the classical formulation leads to stable subspaces mainly made of fast oscillating functions (reflectors). At the same time we prove that MBTT modification ensures appearance of the propagator in these stable subspaces. Numerical experiments prove the feasibility of full inversion for reflected waves in this modified reformulation for the well known Gullfaks velocity model.

AB - Unfortunately we have to admit that after decades of development there are still no reliable techniques of full waveform inversion which guarantee reliable reconstruction of both macrovelocity model and reflectors reconstruction for reasonable acquisitions and frequency ranges. As reasonable we mean realistic offsets (about one-two depths of target objects) and temporal frequency above 5-7 Hz. The paper is devoted to the so-called Migration Based Travel Times (MBTT) formulation of the data misfit functional. This approach relies on the decomposition of a velocity model onto two subspaces - smooth propagator and rough depth reflectors. On this base the modified data misfit functional is introduced and compared with standard least squares formulation. Numerical Singular Value Decomposition proves that these two formulations produce functionals which have almost orthogonal stable subspaces. As is well known the classical formulation leads to stable subspaces mainly made of fast oscillating functions (reflectors). At the same time we prove that MBTT modification ensures appearance of the propagator in these stable subspaces. Numerical experiments prove the feasibility of full inversion for reflected waves in this modified reformulation for the well known Gullfaks velocity model.

UR - http://www.scopus.com/inward/record.url?scp=84971430867&partnerID=8YFLogxK

U2 - 10.3997/2214-4609.201600239

DO - 10.3997/2214-4609.201600239

M3 - Conference contribution

AN - SCOPUS:84971430867

T3 - 7th EAGE Saint Petersburg International Conference and Exhibition: Understanding the Harmony of the Earth's Resources Through Integration of Geosciences

SP - 69

EP - 73

BT - 7th EAGE Saint Petersburg International Conference and Exhibition

PB - European Association of Geoscientists and Engineers, EAGE

Y2 - 11 April 2016 through 14 April 2016

ER -