Retrieval of the physical properties of an anelastic solid half space from seismic data

Full-waveform inversion deals with estimating physical properties of the earth’s subsurface by matching simulated to recorded seismic data. Intrinsic attenuation in the medium leads to the dispersion of propagating waves and the absorption of energy — media with this type of rheology are not perfectly elastic. Accounting for that effect is necessary to simulate wave propagation in realistic geologic media, leading to the need to estimate intrinsic attenuation from the seismic data. That increases the complexity of the constitutive laws leading to additional issues related to the ill-posed nature of the inverse problem. In particular, the joint estimation of several physical properties increases the null space of the parameter space, leading to a larger domain of ambiguity and increasing the number of different models that can equally well explain the data. We have evaluated a method for the joint inversion of velocity and intrinsic attenuation using semiglobal inversion; this combines quantum particle-swarm optimization for the estimation of the intrinsic attenuation with nested gradient-descent iterations for the estimation of the P-wave velocity. This approach takes advantage of the fact that some physical properties, and in particular the intrinsic attenuation, can be represented using a reduced basis, substantially decreasing the dimension of the search space. We determine the feasibility of the method and its robustness to ambiguity with 2D synthetic examples. The 3D inversion of a field data set for a geologic medium with transversely isotropic anisotropy in velocity indicates the feasibility of the method for inverting large-scale real seismic data and improving the data fitting. The principal benefits of the semiglobal multiparameter inversion are the recovery of the intrinsic attenuation from the data and the recovery of the true undispersed infinite-frequency P-wave velocity, while mitigating ambiguity between the estimated parameters.

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Velocity and density profiles of a layered acoustic medium from common source‐point data

Geophysics ◽

10.1190/1.1441356 ◽

1982 ◽

Vol 47 (6) ◽

pp. 898-905 ◽

Cited By ~ 18

Author(s):

Shimon Coen

Keyword(s):

Half Space ◽

Seismic Data ◽

Scattering Theory ◽

Velocity Profiles ◽

Acoustic Medium ◽

Common Source ◽

Density Profiles ◽

Source Point ◽

Surface Data ◽

Point Data

An inverse scattering theory is presented for the unique reconstruction of the density and velocity profiles of a layered acoustic half‐space from common source‐point surface data. The point source is either impulsive or is capable of vibrating at two arbitrary frequencies. An additional datum for the unique reconstruction of these profiles is an estimate of either the highest or lowest velocity within the inhomogeneous acoustic half‐space. Two direct (noniterative) inversion algorithms are developed which construct the density and velocity profiles of the inhomogeneous half‐space from these data. Analytical examples are presented in which all steps in the inversion algorithms are analytically determined. Finally, the paper discusses the potential application of the theory to real seismic data.

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Nonlinear variations of the physical properties along the southern Ecuador subduction channel: Results from depth-migrated seismic data

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2007.11.061 ◽

2008 ◽

Vol 267 (3-4) ◽

pp. 453-467 ◽

Cited By ~ 51

Author(s):

A CALAHORRANOB ◽

V SALLARES ◽

J COLLOT ◽

F SAGE ◽

C RANERO

Keyword(s):

Physical Properties ◽

Seismic Data ◽

Subduction Channel ◽

Southern Ecuador

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Time delays in geophysical consolidation problems

Bulletin of the Seismological Society of America ◽

10.1785/bssa0740041275 ◽

1984 ◽

Vol 74 (4) ◽

pp. 1275-1287

Author(s):

Edo Nyland ◽

Antonio Uribe-Carvajal

Keyword(s):

Physical Properties ◽

Half Space ◽

Time Delays ◽

Delayed Response ◽

Stress Increment ◽

First Order ◽

Boundary Change ◽

History Of ◽

Consistent Formulation ◽

First Order Differential Equations

Abstract The tectonic response of the lithosphere to loads applied over a period of years is one of the few relatively direct ways of measuring lithospheric mechanical properties. We discuss here a method for estimating gross permeability of shallow lithosphere if such a lithosphere can be modeled as a Biot solid. Induced seismicity at artificial lakes sometimes lags the history of lake filling. Clearly this indicates the anomalous load takes some finite time to create a stress increment over the tectonic regime associated with the lake. Such delays may result from diffusion into inhomogeneous regimes, but intuitively it seems that the Biot consolidation theory ought to contain the physics required to produce delayed response in the simplest model, an isotropic half-space with arbitrary vertical layering. The response of such a half-space can be calculated most quickly from matrix solutions of first-order differential equations. We explore here a consistent formulation for the physics of the problem and examine the relation between the rate of diffusion of changes on the boundary, the geometry of the boundary change, and the physical properties of the material. The resulting formulas can be used to estimate probable delays in response of the physical system. Unfortunately, the values of physical properties required to make such estimates are hard to obtain.

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Source to sink studies between the Shaleitian uplift and surrounding sags: Perspectives on the importance of hinterland relief and catchment area for sediment budget, Western Bohai Bay Basin, China

Interpretation ◽

10.1190/int-2017-0027.1 ◽

2017 ◽

Vol 5 (4) ◽

pp. ST65-ST84 ◽

Cited By ~ 4

Author(s):

Xiaomin Zhu ◽

Shunli Li ◽

Qianghu Liu ◽

Zili Zhang ◽

Changgui Xu ◽

...

Keyword(s):

Physical Properties ◽

Seismic Data ◽

Catchment Area ◽

Coarse Grained ◽

Bohai Bay ◽

Tectonic Zone ◽

Clastic Rocks ◽

Source To Sink ◽

Coupling System ◽

Catchment Areas

Source-to-sink system analysis, a cutting-edge topic in the field of earth science, encompasses the whole system, from erosion and transportation to sediment accumulation on the earth’s surface, and involves multidisciplinary collaboration. This current analysis, based on high-precision 3D seismic data, well logs, and other drilling data, using quantitative characterization of the source-to-sink elements, documents that Archean-Proterozoic migmatitic granite, Cambrian-Ordovician carbonate and clastic rocks, and Mesozoic volcaniclastic rocks are developed in the Shaleitian uplift from south to north across large relief differences (up to 2300 m). The relief and size of the catchment in the source area were calculated by denudation recovery, time-depth conversion and high-resolution interpretation on seismic data. Three types of sediment-transporting channel system and 20 catchment areas ([Formula: see text]) were documented around the edges of the uplift: paleovalley channels, fault-controlled channels, and fault-transfer channels. The Paleogene sink is dominated by near-source coarse-grained depositional systems, with the lithofacies characteristics of low lake level (sand rich), lake transgressive (mud rich), and uplift period (sand rich). Three types of boundary conditions developed in the region of the Shaleitian uplift: fault-related steep-slopes (single or multiple), fault ramps, and slope patterns. The bedrock composition, catchment area, channel systems, and fault-border patterns in the Shaleitian uplift jointly controlled the types and scales of sedimentary sandbodies. The south Shaleitian tectonic zone functioned as a high-efficiency coupling system in which reservoir sandbodies were developed (extensive length distance, with well-sorted and round-grained sediments, but weak physical properties). The coupling system for the southwest and west Shaleitian tectonic zones is subordinate (near source and sand rich, sand and mud interbedded, and weak physical properties). The coupling system of the northeast Shaleitian tectonic zone is lowest in efficiency (relatively mud rich).

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Inverting seismic data for rock physical properties; Mathematical background and application

10.1063/1.4952239 ◽

2016 ◽

Author(s):

Mohammed Farfour ◽

Wang Jung Yoon ◽

Jinmo Kim ◽

Jeong-Hwan Lee

Keyword(s):

Physical Properties ◽

Seismic Data ◽

Mathematical Background

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