Cratonic mantle eclogite xenoliths occur with diamond-bearing kimberlite. The modes and mineral compositions of eclogite contain important information on their origin, physical-chemical conditions of formation, and their geophysical properties. We have used the pseudosection option of the program PERPLEX to explore how mineral assemblage, abundance, and composition vary with bulk composition, t...

Temporal changes of seismic properties, such as velocity, attenuation, anisotropy, and scattering properties, have been inferred by active methods for decades and more recently by passive methods. In particular, passive methods are capable of monitoring seismic properties because they do not require earthquakes but rely on continuously excited signals in the ocean, for example, a collection of ...

Seismic reservoir monitoring is a new technology that involves interpreting differences between different generations of 3-D seismic data in terms of changes in reservoir properties over time. A vast number of 3-D seismic surveys are repeated, in whole or in part, for reasons other than reservoir monitoring. In this paper, we cross-equalize two off-the-shelf migrated datacubes over a Gulf of Me...

Low seismic velocity regions in the mantle and crust are commonly attributed to the presence of silicate melts. Determining melt volume and geometric distribution is fundamental to understanding planetary dynamics. We present a new model for seismic velocity reductions that accounts for the anomalous compressibility of silicate melt, rendering compressional wave velocities more sensitive to mel...

We retrieve reflected plane waves by applying seismic interferometry to the recorded ground motion from a cluster of earthquakes. We employ upgoing/downgoing P/S wavefield decomposition, time windows, time reversal, and multi-dimensional deconvolution (MDD) to improve the quality of the extraction of reflected waves with seismic interferometry. Because MDD interferometry requires the separation...

\Velocity Picking" is the problem of picking velocity-time pairs based on a coherence metric between multiple seismic signals. Coherence as a function of velocity and time can be expressed as a 2-D color image representing the \Semblance Velocity." Currently, humans pick velocities by looking at the Semblance Velocity image; picking velocities for a seismic survey can take days or even weeks. A...

a r t i c l e i n f o a b s t r a c t The horizontal Nazca slab, extending over a distance of ∼800 km along the trench is one of enigmatic features in Peruvian subduction zone. Increased buoyancy of the oceanic lithosphere alone due to the subduction of Nazca Ridge is insufficient to fully explain such a lengthy segment. We use data from the recent seismic experiment in southern Peru to find th...

Compressional and shear velocities of rocks are dependent on frequency and this dispersion may be significant even within the seismic band. The amount and position of dispersion will be largely a function of fluid properties, distribution, and motion in the pores. Velocities are thus directly coupled to rock permeability and pore compliance. Propagation often will be in the high frequency regim...

A large-scale data set including time-lapse (4D) elastic attributes and electrical resistivity is generated with the purpose of testing algorithms for reservoir modeling, reservoir characterization, production forecasting, and especially joint time-lapse monitoring using seismic as well as electromagnetic data. The Stanford VI reservoir, which was originally created by Castro et al. (2005), is ...

Materials engineered at the micro- and nanometer scales have had a tremendous and lasting impact in photonics and phononics. At much larger scales, natural soils civil engineered at decimeter to meter scales may interact with seismic waves when the global properties of the medium are modified, or alternatively thanks to a seismic metamaterial constituted of a mesh of vertical empty inclusions b...