Compressional and shear wave properties of marine sediments: Comparisons between theory and data

Buckingham, Michael J.

doi:10.1121/1.1810231

Cited by 152 publications

(103 citation statements)

References 41 publications

(52 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To remedy this situation, a number of researchers [e.g., Stoll, 1983;Chotiros, 1995;Williams, 2001;Williams et al, 2002] have studied models based on the Biot theory of poroelasticity [Biot, 1956a[Biot, , 1956b. Extensions have been made to these models to account for grain contact [Biot, 1962;Tutuncu and Sharma, 1992], stick-slip phenomena [Buckingham, 1997[Buckingham, , 2005, and ''squirt flow'' [Murphy et al, 1986;Dvorkin and Nur, 1993]. While traditional acoustical methods have had difficulty distinguishing experimentally among the predictions of these competing theories, only poroelastic media are capable of generating a macroscopic, EK response.…”

Section: Introductionmentioning

confidence: 99%

Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments

Block¹,

Harris²

2006

J. Geophys. Res.

View full text Add to dashboard Cite

[1] Seismoelectric phenomena in sediments arise from acoustic wave-induced fluid motion in the pore space, which perturbs the electrostatic equilibrium of the electric double layer on the grain surfaces. Experimental techniques and the apparatus built to study the conductivity dependence of the electrokinetic (EK) effect are described, and outcomes for studies in loose glass microspheres and medium-grain sand are presented. By varying the NaCl concentration in the pore fluid, we measured the conductivity dependence of two kinds of EK behavior: (1) the electric fields generated within the samples by the passage of transmitted acoustic waves and (2) the electromagnetic waves produced at the fluid-sediment interface by the incident acoustic wave. Both phenomena are caused by relative fluid motion in the sediment pores; this feature is characteristic of poroelastic (Biot) media but is not predicted by either viscoelastic fluid or solid models. A model of plane wave reflection from a fluid-sediment interface using EK-Biot theory leads to theoretical predictions that compare well to the experimental data for both loose glass microspheres and medium-grain sand.Citation: Block, G. I., and J. G. Harris (2006), Conductivity dependence of seismoelectric wave phenomena in fluid-saturated sediments,

show abstract

Section: Introductionmentioning

confidence: 99%

Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments

Block¹,

Harris²

2006

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…Para Buckingham (2005), em sedimentos que variam desde o cascalho até a argila, um aumento da granulometria representa um aumento nos valores da velocidade. De acordo com os valores apresentados na Tabela 2, a presença de lama arenosa provocou um aumento nas velocidades quando comparadas com a lama compacta.…”

Section: Perfis De Velocidadeunclassified

Parâmetros físicos de sedimentos marinhos superficiais da região costeira de Caravelas, Sul da Bahia

Falcão¹,

Neto²

2010

Rev. Bras. Geof.

View full text Add to dashboard Cite

ABSTRACT. This research combines geological data obtained from core samples and geophysical properties in order to investigate how geological and sedimentological parameters affect the velocity of P-waves in near surface marine sediments, The velocity of P-waves (V p), gamma density, acoustic impedance and magnetic susceptibility were correlated with core geology of four core of the coastal region of Caravelas, Bahia State. Geophysical properties were acquired using the MSCL (MultiSensor Core Logger). Core were opened and described according to grain size, color, compaction degree. Eight different kinds of sediments were recognized:shell, coarse to very coarse sand, medium sand, fine to very fine sand, sandy mud, compact mud, fluid mud, and very fluid mud. The results showed that, in general, the highest values of V p and density and the lowest values of magnetic susceptibility are related to the coarser sediments. Very coarse sediments and shells showed erratic values basically due to the low compaction of these materials. The acoustic impedance and reflection coefficient profiles were useful to detect sediments interface. More detailed grain size analysis were conducted at the sandy mud section of core JP-112 and corroborated the relationship between V p and grain size.Keywords: P-wave velocity, magnetic susceptibility, shallow sediments, Caravelas. RESUMO.Este trabalho combina informações obtidas por testemunhos de sondagem com dados adquiridos por perfilagem geofísica a fim de verificar a influência dos parâmetros geológicos e sedimentológicos na velocidade de ondas P em sedimentos marinhos superficiais. Dados de velocidade da onda compressional (V p), densidade gama, impedância acústica e susceptibilidade magnética foram correlacionados com dados geológicos de quatro testemunhos coletados na zona costeira da cidade de Caravelas, estado da Bahia. As propriedades geofísicas foram obtidas utilizando como sistema de medição o perfilador multisensor de testemunhos (MultiSensor Core Logger -MSCL). Os testemunhos foram descritos segundo a geologia, cor e grau de compactação. Oito tipos distintos de sedimentos foram observados: conchas, areia grossa a muito grossa, areia média, areia muito fina a fina, lama arenosa, lama compacta, lama fluida e lama muito fluida. Os resultados mostram que, de maneira geral, os maiores valores de velocidade e densidade, inversamente proporcionais aos de susceptibilidade magnética, estão associados aos sedimentos de maior granulometria. Os valores de V p para areia muito grossa e conchas mostrou-se errático devidoà falta de compactação desses materiais. Os gráficos de impedância acústica e do coeficiente de reflexão facilitaram a identificação de interfaces e apresentaram coerência em relação aos perfis de velocidade e de densidade. Medições de granulometria foram realizadas na seção de lama arenosa do testemunho JP-112, para ratificar a relação da variabilidade dos parâmetros físicos com a classificação granulométrica utilizada para a caracterização dos quatro testemunhos.Palavras-c...

show abstract

“…The slotshaped sample geometry accommodates the rectangular footprint of a 32 element P-wave phased array (47.9 mm x 15.0 mm). The shorter dimension across the slot also allows measurement of strongly attenuating, short-wavelength ultrasonic shear waves that result from the low shear wave velocities in unconsolidated clay-rich sediments (V S < 500 m/s; Leurer, 2004;Buckingham, 2005). Compaction of relatively compliant clay-rich sediments and unconsolidated sands is approximately one-dimensional (i.e., uniaxial strain) because of the small lateral deformation provided by the thick (>1.5 cm) stainless steel walls of the cell.…”

Section: Apparatus Design Considerationsmentioning

confidence: 99%

Phased array compaction cell for measurement of the transversely isotropic elastic properties of compacting sediments

et al. 2011

View full text Add to dashboard Cite

Sediments undergoing compaction exhibit transversely isotropic (TI) elastic properties that are described by five elastic constants. Continuous determination of all five constants in the laboratory during compaction is a difficult task. In this paper, we present a new experimental apparatus, the phased array compaction cell, for measuring the TI elastic properties of clay-rich sediments under uniaxial strain consolidation conditions. This apparatus uses matched sets of P-and S-wave ultrasonic transducers located along the sides of the sample and an ultrasonic P-wave phased array source together with a miniature P-wave receiver on the top and bottom ends of the sample. The phased array provides plane P-waves that are used to measure phase velocities over a range of angles. From these measurements, the five TI elastic constants can be recovered as the sediment is compacted, without the need for sample unloading, re-coring, or reorienting. Descriptions of the apparatus, data processing and an application demonstrating recovery of the evolving TI properties of a compacting marine sediment sample are provided in this paper.

show abstract

Compressional and shear wave properties of marine sediments: Comparisons between theory and data

Cited by 152 publications

References 41 publications

Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments

Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments

Parâmetros físicos de sedimentos marinhos superficiais da região costeira de Caravelas, Sul da Bahia

Phased array compaction cell for measurement of the transversely isotropic elastic properties of compacting sediments

Contact Info

Product

Resources

About