Laboratory experiments on compressional ultrasonic wave attenuation in partially frozen brines

Geophysics ◽  
2008 ◽  
Vol 73 (2) ◽  
pp. N9-N18 ◽  
Author(s):  
Jun Matsushima ◽  
Makoto Suzuki ◽  
Yoshibumi Kato ◽  
Takao Nibe ◽  
Shuichi Rokugawa
Keyword(s):  
Ultrasonic Wave ◽  
Laboratory Experiments ◽  
Wave Attenuation ◽  
Ultrasonic Attenuation ◽  
Liquid System ◽  
Seismic Attenuation ◽  
Ultrasonic Waves ◽  
Frequency Range ◽  
Pore Microstructure ◽  
Solid Liquid

Often, the loss mechanisms responsible for seismic attenuation are unclear and controversial. We used partially frozen brine as a solid-liquid coexistence system to investigate attenuation phenomena. Ultrasonic wave-transmission measurements on an ice-brine coexisting system were conducted to examine the influence of unfrozen brine in the pore microstructure on ultrasonic waves. We observed the variations of a 150–1000 kHz wave transmitted through a liquid system to a solid-liquid coexistence system, changing its temperature from [Formula: see text] to –[Formula: see text]. We quantitatively estimated attenuation in a frequency range of [Formula: see text] by considering different distances between the source and receiver transducers. We also estimated the total amount of frozen brine at each temperature by using the pulsed nuclear magnetic resonance (NMR) technique and related those results to attenuation results. The waveform analyses indicate that ultrasonic attenuation in an ice-brine coexisting system reaches its peak at [Formula: see text], at which the ratio of the liquid phase to the total volume in an ice-brine coexisting system is maximal. Finally, we obtained a highly positive correlation between the attenuation of ultrasonic waves and the total amount of unfrozen brine. Thus, laboratory experiments demonstrate that ultrasonic waves within this frequency range are affected significantly by the existence of unfrozen brine in the pore microstructure.

Rock-physics modeling of ultrasonic P- and S-wave attenuation in partially frozen brine and unconsolidated sand systems and comparison with laboratory measurements

Geophysics ◽  
2019 ◽  
Vol 84 (5) ◽  
pp. MR153-MR171 ◽  
Author(s):  
Linsen Zhan ◽  
Jun Matsushima
Keyword(s):  
Ultrasonic Wave ◽  
Wave Attenuation ◽  
Freezing Point ◽  
Rock Physics ◽  
Ultrasonic Waves ◽  
P Wave ◽  
Dominant Factor ◽  
S Wave ◽  
High Attenuation ◽  
Unconsolidated Sand

The nonintuitive observation of the simultaneous high velocity and high attenuation of ultrasonic waves near the freezing point of brine was previously measured in partially frozen systems. However, previous studies could not fully elucidate the attenuation variation of ultrasonic wave propagation in a partially frozen system. We have investigated the potential attenuation mechanisms responsible for previously obtained laboratory results by modeling ultrasonic wave transmission in two different partially frozen systems: partially frozen brine (two phases composed of ice and unfrozen brine) and unconsolidated sand (three phases composed of ice, unfrozen brine, and sand). We adopted two different rock-physics models: an effective medium model for partially frozen brine and a three-phase extension of the Biot model for partially frozen unconsolidated sand. For partially frozen brine, our rock-physics study indicated that squirt flow caused by unfrozen brine inclusions in porous ice could be responsible for high P-wave attenuation around the freezing point. Decreasing P-wave attenuation below the freezing point can be explained by the gradual decrease of squirt flow due to the gradual depletion of unfrozen brine. For partially frozen unconsolidated sand, our rock-physics study implied that squirt flow between ice grains is a dominant factor for P-wave attenuation around the freezing point. With decreasing temperature lower than the freezing point, the friction between ice and sand grains becomes more dominant for P-wave attenuation because the decreasing amount of unfrozen brine reduces squirt flow between ice grains, whereas the generation of ice increases the friction. The increasing friction between ice and sand grains caused by ice formation is possibly responsible for increasing the S-wave attenuation at decreasing temperatures. Then, further generation of ice with further cooling reduces the elastic contrast between ice and sand grains, hindering their relative motion; thus, reducing the P- and S-wave attenuation.

Laboratory experiments on ultrasonic wave attenuation in partially frozen brines

2007 ◽  
Author(s):  
Jun Matsushima ◽  
Makoto Suzuki ◽  
Yoshibumi Kato ◽  
Shuichi Rokugawa
Keyword(s):  
Ultrasonic Wave ◽  
Laboratory Experiments ◽  
Wave Attenuation

A direct comparison between vibrational resonance and pulse transmission data for assessment of seismic attenuation in rock

Geophysics ◽  
1990 ◽  
Vol 55 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Dane P. Blair
Keyword(s):  
Elastic Scattering ◽  
Wave Attenuation ◽  
Seismic Attenuation ◽  
Experimental Results ◽  
P Wave ◽  
Whole Body ◽  
Frequency Range ◽  
Vibrational Resonance ◽  
Fine Grained ◽  
Pulse Transmission

For the same volume of rock, I compare the attenuation obtained by seismic pulse transmission over the frequency range 1–150 kHz with that obtained by vibrational resonance techniques over the frequency range 1–50 kHz. The initial studies were performed on a rectangular block of medium‐grained granite which was large enough to permit the installation of a seismic pulse transmission array over a 1.8 m path length, yet small enough to permit whole‐body resonance. A Q of 82, for the P wave, was derived from the vibrational resonance results, whereas a Q of 15 was derived from the pulse transmission results. In light of models proposed for the viscoelastic, geometric, and elastic scattering attenuation mechanisms, the experimental results suggest that this large discrepancy in Q values is due to elastic scattering by grain clusters (rather than individual grains) within the granite. Scattering is significant in the high‐frequency pulse transmission tests, but is considered insignificant in the lower frequency resonance tests. Furthermore, this scattering is represented approximately by a constant-Q loss mechanism, which makes it difficult to separate unambiguously elastic scattering and viscoelastic losses. Subsequent studies performed on a large block of fine‐grained norite yield a resonance Q of 89 and a pulse Q of approximately 102 and suggest a negligible scattering loss for this material. The experimental results for the norite imply that the constant-Q theory of seismic pulse attenuation provides a reasonable description of wave attenuation in a dry, fine‐grained crystalline rock over the frequency range 1–150 kHz.

scholarly journals Acoustic Vibrational Properties and Fractal Bond Connectivity of Praseodymium Doped Glasses

2000 ◽  
Vol 53 (6) ◽  
pp. 805
Author(s):  
H. B. Senin ◽  
H. A. A. Sidek ◽  
G. A. Saunders
Keyword(s):  
Hydrostatic Pressure ◽  
Bulk Modulus ◽  
Ultrasonic Wave ◽  
Mole Fraction ◽  
Wave Attenuation ◽  
Elastic Stiffness ◽  
Ultrasonic Waves ◽  
Elastic Behaviour ◽  
Doped Glasses ◽  
Two Level Systems

The velocities of longitudinal and shear ultrasonic waves propagated in the (Pr2O3)x(P2O5)1-x glass system, where x is the mole fraction of Pr2O3 and (1 - x) is the mole fraction of P2O5, have been measured as functions of temperature and hydrostatic pressure. The temperature dependencies of the second order elastic stiffness tensor components (SOEC) CS IJ , which have been determined from the velocitydata between 10 and 300 K, show no evidence of phonon mode softening throughout the whole temperature range. The elastic stiffnesses increased monotonically, the usual behaviour associated with the effect of the phonon anharmonicityof atomic vibration. At low temperatures, strong phonon interactions with two-level systems have been observed. The ultrasonic wave attenuation of longitudinal and shear waves is dominated bya broad acoustic loss peak whose height and peak position are frequencydependent. This behaviour is consistent with the presence of thermally activated structural relaxation of the two-level systems in these glasses. The fractal bond connectivity of these glasses, obtained from the elastic stiffnesses determined from ultrasonic wave velocities, has a value between 2.32 to 2.55, indicating that their connectivitytends towards having a threedimensional character. The hydrostatic pressure dependencies of longitudinal ultrasonic waves show a slight increase with pressure. As a consequence, the hydrostatic pressure derivatives ( CS11/ P)P=0 of the elastic stiffness CS11/ and (BS/P)P=0 of the bulk modulus BS of (Pr2O3)x(P2O5)1-x glasses are positive. The bulk modulus increases with pressure, and thus these glasses stiffen under pressure, which is associated with the normal elastic behaviour. The GrÜneisen parameter approach has been used to quantifythe vibrational anharmonicityof the long-wavelength acoustic phonons in these glasses.

Enhancing Matrix Acid Stimulation Using Ultrasonic Waves

2021 ◽  
Author(s):  
Mohammed H. Khaldi ◽  
Sinan Caliskan ◽  
Mohamed N. Noui-Mehidi
Keyword(s):  
Ct Scan ◽  
Ultrasonic Wave ◽  
Laboratory Experiments ◽  
Ultrasonic Waves ◽  
Matrix Acidizing ◽  
Rate Of Penetration ◽  
The Core ◽  
Core Samples ◽  
Carbonate Formation ◽  
Ct Scan Analysis

Abstract The present paper is concerned with improving matrix acidizing in carbonate formation. For this purpose, ultrasonic waves were added to conventional matrix acid stimulation to increase the acid reach inside the rock. This concept is based on a phonophoresis effect of the acid, applying a similar concept in pushing the stimulation acid deeper in the formation during matrix acidizing. This effect will have a great benefit in reaching larger stimulated areas and increasing the overall well productivity. Extensive laboratory experiments have shown that the rate of penetration of the acid when exposed simultaneously to ultrasonic wave irradiation reached almost 90% more than the acid only. This phenomena has been investigated through the use of CT scan analysis on the core samples. The penetration was instantaneous and rapid in reaching deeper length of the plug sample.

Experimental Self-Location Vehicle Based on Ultrasonic Waves Guided System

1993 ◽  
Vol 30 (3) ◽  
pp. 224-235
Author(s):  
Robert Sh. Habib ◽  
Harootyun Sh. Habib ◽  
Bassam S. Majeed
Keyword(s):  
Ultrasonic Wave ◽  
Laboratory Experiments ◽  
Dynamic Performance ◽  
Ultrasonic Waves ◽  
System Dynamic ◽  
Automated Guided Vehicle ◽  
Location System ◽  
Design And Implementation

Experimental self-location vehicle based on an ultrasonic wave-guided system This paper describes the design and implementation of an automated guided vehicle, based on a microcomputer-controlled ultrasonic self-location system. Dynamic performance and system repeatability are evaluated by tests carried out on the applied self-navigating algorithm. The system is suitable for robotics or FMS laboratory experiments utilising the implemented hardware and relevant software.

Longitudinal Ultrasonic Attenuation in Tantalum at Frequencies up to 1 GHz

1971 ◽  
Vol 49 (3) ◽  
pp. 296-301 ◽  
Author(s):  
J. M. Perz ◽  
W. A. Roger
Keyword(s):  
Magnetic Field ◽  
Thin Film ◽  
Frequency Dependence ◽  
Normal State ◽  
Superconducting State ◽  
Ultrasonic Attenuation ◽  
Mean Free Path ◽  
Ultrasonic Waves ◽  
Frequency Range ◽  
Conduction Electrons

The attenuation due to interaction with conduction electrons of longitudinal sound propagating along [110] in a Ta crystal of resistance ratio 390 has been measured over the frequency range 0.46 to 1.0 GHz. The product of the wave vector q and the electronic mean free path l determined from the frequency dependence of the normal state attenuation ranges over 1.8 < ql < 3.8. The attenuation in the superconducting state in the absence of a magnetic field fits the BCS expression for 1.2 < T < Tc = 4.46 K with 2Δ(0) = 3.62 ± 0.06 kTc. The ultrasonic waves have been generated by thin film CdS transducers, and the conversion efficiency has been found to vary inversely with the active area of the transducer.

HOW GAS HYDRATE SATURATION AND MORPHOLOGY CONTROL SEISMIC ATTENUATION: A CASE STUDY FROM THE SOUTH HYDRATE RIDGE

2021 ◽  
pp. 1-63
Author(s):  
Aoshuang Ji ◽  
Tieyuan Zhu ◽  
Hector Marin-Moreno ◽  
Xiong Lei
Keyword(s):  
Gas Hydrate ◽  
Wave Attenuation ◽  
Rock Physics ◽  
Seismic Profile ◽  
Seismic Attenuation ◽  
P Wave ◽  
Frequency Range ◽  
The South ◽  
Hydrate Ridge ◽  
Hydrate Saturation

Prior studies have shown an ambiguous relationship between gas hydrate saturation and seismic attenuation in different regions, but the effect of gas hydrate morphology on seismic attenuation of hydrate-bearing sediments was often overlooked. Here we combine seismic data with rock physics modeling to elucidate how gas hydrate saturation and morphology may control seismic attenuation. To extract P-wave attenuation, we process both the vertical seismic profile (VSP) data within a frequency range of 30 – 150 Hz and sonic logging data within 10 – 15 kHz from three wells in the south Hydrate Ridge, offshore of Oregon (USA), collected during Ocean Drilling Program (ODP) Leg 204 in 2000. We calculate P-wave attenuation using spectral matching and centroid frequency shift methods, and use Archie's relationship to derive gas hydrate saturation from the resistivity data above the bottom simulating reflection (BSR) at the same wells. To interpret observed seismic attenuation in terms of the effects of both gas hydrate saturation and morphology, we employ the Hydrate-Bearing Effective Sediment (HBES) rock physics model. By comparing the observed and model-predicted attenuation values, we infer that: (1) seismic attenuation appears to not be dominated by any single factor, instead, its variation is likely governed by both gas hydrate saturation and morphology; (2) the relationship between seismic attenuation and gas hydrate saturation varies with different hydrate morphologies; (3) the squirt flow, occurring at different compliances of adjacent pores driven by pressure gradients, may be responsible for the significantly large or small attenuation over a broad frequency range.

Bell pepper maturity determination by ultrasonic techniques

2010 ◽  
Vol 6 (1) ◽  
pp. 17-34 ◽  
Author(s):  
Timea Ignat ◽  
Amos Mizrach ◽  
Ze’ev Schmilovitch ◽  
József Felföldi
Keyword(s):  
Ultrasonic Wave ◽  
Wave Attenuation ◽  
Ultrasonic Attenuation ◽  
Principal Component ◽  
Soluble Solids ◽  
Small Samples ◽  
Pcr Analysis ◽  
Mechanical Relaxation ◽  
Physical Parameters ◽  
Weight Percentage

Ultrasonic wave attenuation within the flesh of intact greenhouse-grown pepper (Capsicum annum L.) fruits was measured during growth, to try to correlate this attenuation with quality-related physical properties: firmness, dry weight percentage (DW%) and total soluble solids (TSS) contents, and chemical composition. Twenty examples of each of three cultivars were picked weekly during a 7-week growth period, and weight, color, and ultrasonic wave attenuation were recorded, to nondestructively trace the changes during growth, and each intact pepper was then subjected to a relaxation test to determine firmness. Then, small samples of fruit flesh were destructively analyzed to determine DW% and TSS.During the 55th to the 65th day after flowering the fruits of all three cultivars reached their maximum weight, color started to change, and DW% and TSS started to increase rapidly; and the fruits were nondestructively examined by mechanical relaxation and ultrasonically. Principal component regression (PCR) analysis revealed significant (95%) correlation between ultrasonic attenuation, TSS and physical parameters. A TSS prediction model was developed for all three cultivars.

Modelling of Heat Generation and Resultant Temperature Distribution Due to the Passage of an Ultrasonic Wave Through a Mixture of Polyborosiloxane and Silicon Carbide

1994 ◽  
Vol 208 (5) ◽  
pp. 299-306
Author(s):  
A J Fletcher ◽  
A Fioravanti
Keyword(s):  
Silicon Carbide ◽  
Ultrasonic Wave ◽  
Heat Generation ◽  
Wave Attenuation ◽  
Ultrasonic Attenuation ◽  
Numerical Technique ◽  
Dominant Role ◽  
Frictional Heating ◽  
Internal Heat ◽  
Transfer Equations

A mixture of polyborosiloxane and silicon carbide abrasive has been agitated using an ultrasonic system. The passage of the ultrasonic wave through this mixture resulted in an increase in temperature due to conversion of energy from the ultrasonic wave into heat. This investigation was initially concerned with the calculation of the heat-generation term, from a knowledge of the attenuation of the acoustic wave. The second stage of the analysis involved the solution of the relevant transient heat-transfer equations for conduction and convection with internal heat generation. The solution to these equations was obtained using a numerical technique. Temperatures at various positions within the system were measured using suitable equipment. These experimental data were compared against the results of the calculation and it was found that significant discrepancies existed between the two sets of results when the analysis considered heat generation as a sole function of wave attenuation. In an attempt to improve the correlation between calculated and measured temperatures the analysis was developed to include a heat-generation term acting at the interface between the sonotrode and the transmission medium. Such heat generation would be produced by frictional heating at the interface, and this would be associated with poor coupling between the acoustic source and the medium. It was found that the correlation between calculated and measured temperatures improved greatly on adoption of the frictional heating analysis, which leads to the suggestion that heating within the medium is a function of both ultrasonic attenuation and frictional heating. For the conditions specified the latter appears to have a dominant role.

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