P-wave Velocity Measurements Research Articles

A numerical and experimental investigation on seismic anisotropy of Finero peridotite, Ivrea-Verbano Zone, Northern Italy

The Ivrea-Verbano Zone offers a unique opportunity to study lower crust/upper mantle rocks unaffected by serpentinization. Peridotites from Finero (North-East Ivrea-Verbano Zone) have been collected to investigate the influence of individual mineral phases on seismic anisotropy. The methods involve experimental ultrasonic P-wave velocity measurements using a hydrostatic pressure vessel, and electron backscatter diffraction (EBSD) analysis to investigate the crystallographic preferred orientation (CPO). CPO was analyzed by large area EBSD scans for major minerals including olivine, orthopyroxene, but also for metasomatic hornblende. The CPO of olivine is confirmed to be the major source of detected seismic anisotropy. Minor influence can arise from hornblende if it is sufficiently abundant.

Effect of methane hydrate morphology on compressional wave velocity of sandy sediments: Analysis of pressure cores obtained in the Eastern Nankai Trough

Sediment cores containing methane hydrate were obtained under pressure from the Eastern Nankai Trough offshore Japan, and they have been analyzed to investigate the relationship between compressional wave velocity (P-wave velocity), methane hydrate saturation, and pore space hydrate morphology. P-wave velocities of pressure cores were measured at near in-situ pressures, thus preventing hydrate dissociation. After the measurement of P-wave velocity, the cores were cut, under pressure, into separate P-wave velocity intervals. Each core interval was depressurized while measuring the evolved gas volume to quantify methane hydrate saturation. The results show that P-wave velocity correlates well with hydrate saturation; the P-wave velocity varied from less than 1700 m/s in the hydrate-free section to greater than 2300 m/s in the section with the highest hydrate saturation of 72%. The measured P-wave velocities were correctly reproduced by the sediment frame component model by adjusting model parameters such as sand-clay ratio and effective stress. It was found that all core data plotted within the model predictions assuming zero effective stress and assuming in situ effective stress. This may indicate that the cores were in the process of relaxing from their in situ effective stress at the time of measurement. By using pressure cores and pressure core analysis technology, the relationship between P-wave velocity and methane hydrate saturation has been directly obtained nondestructively. The observed relationship in high-resolution core-scale specimens enables estimation of the hydrate morphology and is expected to be more accurate than cross-plot data in well logging.

A robust experimental determination of Thomsen’s δ parameter

A novel inversion method for the laboratory determination of Thomsen’s [Formula: see text] anisotropy parameter on cylindrical rock specimens from ultrasonic data has been recently reported in the literature. We further assessed this method through a direct comparison of the results of the traditional method (involving a single off-axis P-wave velocity measurement at 45°) and the new method (involving 65 P-wave velocity measurements at several angles to the symmetry axis). We prepared and characterized two vertical shale specimens from the same preserved vertical core to assess their similarity in terms of structure, mineralogy, porosity, and density. The shale was assumed to be transversely isotropic in view of the observed (horizontal) bedding. We subjected both specimens to the same brine saturation and effective stress state. Using the two methods, we obtained similar results for Thomsen’s [Formula: see text] (vertical P-wave) and [Formula: see text] (P-wave anisotropy) parameters. However, a significant discrepancy was observed for Thomsen’s [Formula: see text] parameter: We obtained results of 0.13 using the new method and 0.39 using the traditional method. As a result of the overdetermined nature of the P-wave velocity measurements used in the new method, we believe that the corresponding [Formula: see text] value is more reliable. Also, the value derived with the new testing method seems to match more closely the reported field data.

The physical nature of thermal conduction in dry granular media

This paper documents the results of a laboratory experimental study conducted to explore the relative contributions of phonon and electron heat conduction in an electrically conductive granular material under increasing confining stresses. The thermal conductivity of Ottawa sand under increasing confinement was also studied to offer a baseline for comparison. Simultaneous measurements of thermal conductivity, electrical conductivity and p-wave velocity were used to develop a parallel conduction model capable of predicting the thermal conductivity of dry granular media. The results suggest that the thermal conductivity of dry granular media is governed by the stiffness of the packing, regardless of whether it is electrically conductive or not. Furthermore, p-wave velocity measurements can be used to estimate the thermal conductivity of electrically conductive (granular lead) and non-conductive (Ottawa sand) granular media.

Heterogeneities and diagenetic control on the spatial distribution of carbonate rocks acoustic properties at the outcrop scale

Carbonate rocks are characterized by a high heterogeneity of their properties at the outcrop scale that results from complex interactions between sedimentary, diagenetic and fracturing processes. Here we show acoustic P-wave velocity measurements conducted step-by-step on three decameter scale outcrop surfaces in Cretaceous carbonate rocks with contrasted heterogeneities: two shallow water highly-fractured (Cassis) and low-fractured (Calissanne) carbonates, and one basin highly-compacted (Grignantes). P-wave measurements were compared to outcrop geology, and with plug porosity, P-wave velocity laboratory measurements and a thin-section study.Results show a strong scale dependence of P-wave velocities which always are lower at the decimeter scale than at the plug scale. Vpin situ-versus-Vpplug large discrepancies (>2000m/s) highlight the signature of large heterogeneities (open fractures, stylolithes), and lower discrepancies (<2000m/s) highlight the signature of small matrix heterogeneities (porosity type, granulometry, and fracture filling). Variogram analyses were conducted to precise the contrasted outcrop scale Vp signatures. The oblique anisotropy Vpin situ distribution follows the dip of the ripple foresets which are controlling grain sorting and porosity in Calissanne outcrop, the near-isotropic Vp are explained by an early intense fracturing and cementation in Cassis outcrop and the strong horizontal anisotropy with a hole effect behavior on variograms highlights the late re-opening of multiple intervals of compaction bands in Grignantes. These results illustrate that the early diagenesis coupled to fracture or stylolithe reactivation/opening are two key processes that explain the outcrop scale P-wave velocity distribution anisotropy in carbonates.

Carbonate pore system evaluation using the velocity–porosity–pressure relationship, digital image analysis, and differential effective medium theory

Abstract Carbonate reservoirs exhibit heterogeneous pore systems and a wide variety of grain types, which affect the rock's elastic properties and the reservoir parameter relationships. To study the Albian carbonates in the Campos Basin, a methodology is proposed to predict the amount of microporosity and the representative aspect ratio of these inclusions. The method assumes three pore-space scales in two representative inclusion scenarios: 1) a macro–mesopore median aspect ratio from the thin-section digital image analysis (DIA) and 2) a microporosity aspect ratio predicted based on the measured P-wave velocities. Through a laboratory analysis of 10 grainstone core samples of the Albian age, the P- and S-wave velocities (Vp and Vs) are evaluated at effective pressures of 0–10 MPa. The analytical theories in the proposed methodology are functions of the aspect ratios from the differential effective medium (DEM) theory, the macro–mesopore system recognized from the DIA, the amount of microporosity determined by the difference between the porosities estimated from laboratorial helium-gas and the thin-section petrographic images, and the P-wave velocities under dry effective pressure conditions. The DIA procedure is applied to estimate the local and global parameters, and the textural implications concerning ultrasonic velocities and image resolution. The macro–mesopore inclusions contribute to stiffer rocks and higher velocities, whereas the microporosity inclusions contribute to softer rocks and lower velocities. We observe a high potential for this methodology, which uses the microporosity aspect ratio inverted from Vp to predict Vs with a good agreement. The results acceptably characterize the Albian grainstones. The representative macro–mesopore aspect ratio is 0.5, and the inverted microporosity aspect ratio ranges from 0.01 to 0.07. The effective pressure induced an effect of slight porosity reduction during the triaxial tests, mainly in the microporosity inclusions, slightly changing the amount and the aspect ratio of the microporosity.

Study cases of thermal conductivity prediction from P-wave velocity and porosity

Laboratory measurements of porosity, P-wave velocity and thermal conductivity from samples from two geothermal reservoirs in France and Australia are compared to the predictions from different models involving mineralogical considerations, and effective medium theory models yields <10% error in dry and saturated conditions in the Australian aquifer, and <30% deviation under saturated conditions in the French reservoir. Thermal conductivity derived from models involving detailed mineralogy is in good agreement with laboratory-measured data. Possible explanations for minor discrepancies using SEM/XRD include the effects of secondary minerals (i.e. ±undetected carbonates and fine particles) and the hydration of clays.

Feasibility of Using a Seismic Surface Wave Method to Study Seasonal and Weather Effects on Shallow Surface Soils

The objective of this paper is to study the feasibility of using a seismic surface wave method to investigate seasonal and weather effects on shallow surface soils. In the study, temporal variations of subsurface soil properties were measured and monitored by using a combination of a new seismic surface method and an existing acoustic probe system. A laser Doppler vibrometer (LDV)-based multi-channel analysis of surface wave (MASW) method is developed to measure the soil profile in terms of shear wave velocity at depths up to a few meters. While the conventional MASW uses geophones as surface vibration sensors, the present MASW uses a moving LDV as a non-contact sensor to detect Rayleigh wave propagation generated by an electromagnetic shaker operating in chirp mode. A long-term survey was conducted by measuring the S-wave velocity profile with the MASW along with measurements of soil temperature, water content, water potential, and P-wave velocity with the acoustic probe system. The results from the two methods are compared and interpreted with the concept of the effective stress, governed by soil suction stress for top unsaturated soils and by overburden pressure for deeper layers of soils. This study demonstrates that the S-wave velocity images obtained from the LDV-MASW method can effectively monitor and visualize the temporal and spatial variations of subsurface soil properties caused by seasonal and weather effects.

On a possibility of reconstruction of Cosserat moduli in particulate materials using long waves

The paper proposes a method of reconstruction of the Cosserat elastic moduli using the measurements of velocities of the p-wave and the high-frequency twist wave as well as the low-frequency asymptotics of a shear wave dispersion relationship. It is shown that in the case of a general isotropic Cosserat continuum, the information obtained from these wave measurements is insufficient for the complete moduli reconstruction. The reconstruction is shown to be possible in the case of a 3D isotropic Cosserat continuum governed by at most four independent parameters. Such a continuum is suggested for a particulate material consisting of spherical particles connected by normal, shear and rotational links. Another case when the full reconstruction is possible consists of 2D orthotropic Cosserat continuum modelling particulate material with square packing of cylindrical particles and 2D isotropic Cosserat continuum modelling with hexagonal packing of cylindrical particles. In the 2D materials, the measurements of p-wave velocity and the shear wave dispersion relationship are sufficient for complete reconstruction of all moduli. A phase shift method and reconstruction algorithms are presented.

Hysteretic Elastic Wave Velocity and Attenuation in Partially Saturated Sandstone by CO2 and Brine: Evidenced by an Experimental Study with X-ray CT

Abstract We present the results of an experiment for the measurement of P-wave velocity and attenuation in a sandstone saturated by supercritical CO 2 (scCO 2 ) and brine at ultrasonic frequency. In this study, we acquired simultaneously time-lapse records of ultrasonic waveforms and X-ray CT images of fluid saturation. Therefore, the quantitative relationships of P wave velocity and attenuation versus CO 2 saturation in local wave pass zone were obtained. The results show obvious hysteresis between drainage and imbibition for these relationships. The imbibition exhibits lower velocity and high attenuation than drainage at the same CO 2 saturation. For example, the velocity has a 6% reduction during drainage, while a 13% reduction during imbibition at 0.3 CO 2 saturation. Moreover, the data during transition between drainage and imbibition shows retardation phenomenon, e.g. the velocity continues decreasing while CO 2 saturation starts decreasing. We explain the hysteresis using the White's model, which suggest the patch size and patch saturation change from drainage to imbibition.

Permeability evolution in fractured coal — Combining triaxial confinement with X-ray computed tomography, acoustic emission and ultrasonic techniques

Cyclic loading of coals impacts permeability due to reversible deformation and irreversible damage and extension to pre-existing fracture networks. These changes in permeability influence the effectiveness of degassing of coal prior to mining, the recovery of coalbed methane by both conventional and enhanced methods and potential for sequestration of CO2. We explore these interactions of stress and damage that contribute to changes in permeability through imaging with X-ray computed tomography (X-ray CT), acoustic emission (AE) profiling together with the concurrent measurement of P-wave velocities. We use these techniques to examine the evolution of the 3D fracture network during stressing through failure. A total of five semi-anthracite/anthracite coal cores (~40mm in diameter and 80mm in length) are sequentially loaded to failure (~37.53MPa) with concurrent measurements of permeability. Intermittent scanning by X-ray CT, AE profiling and measurement of the evolving P-wave velocity effectively determine changes in the 3D fracture network with applied stress. These results are correlated with the “V-shaped” variation of permeability with increasing axial stress under the imposed triaxial stress conditions. This is consistent with observations on hard rocks where increasing stresses initially close fractures before fractures ultimately dilate, propagate and coalesce as the peak strength is reached. The increase in fracture volume is non uniform within the sample and is largest at the end platens. The permeability evolution was similarly dynamic with coal permeability reduced by one to two orders of magnitude in some cores (0.18–0.004mD) until increasing dramatically as failure is approached (14.07–37.53MPa).

Small-strain constrained elastic modulus of clean quartz sand with various grain size distribution

Approx. 120 resonant column (RC) tests with additional P-wave velocity measurements using piezoelectric elements have been performed on 19 clean quartz sands with piecewise linear, gap-graded, S-shaped or other smoothly shaped grain size distribution curves. For each material different pressures and densities were tested. It is demonstrated that the extended empirical equations for the small-strain constrained elastic modulus proposed by the authors in an earlier paper work well also for most of the more complex grain size distribution curves tested in the present study. These equations considering the influence of the uniformity coefficient of the grain size distribution curve were developed based on the data from tests on linear gradations. A further improvement of the prediction for the more complex grain size distributions can be achieved if the correlation equations are applied with a specially defined average inclination of the grain size distribution curve. Such an improvement is demonstrated not only for the small-strain constrained elastic modulus, but also for small-strain shear modulus, modulus degradation and Poisson's ratio.

Estimation of CO2 saturation during both CO2 drainage and imbibition processes based on both seismic velocity and electrical resistivity measurements

SUMMARY In order to monitor injected carbon dioxide (CO2), simultaneous measurements of seismic velocity and electrical resistivity are employed during the drainage (CO2 injection) and imbibition (water injection) processes of a Berea sandstone. Supercritical CO2 (10 MPa at 40 o C) was injected into a water-saturated Berea sandstone in the drainage stage and monitored via simultaneous measurements. After the injection of supercritical CO2, fresh distilled water was injected into the CO2-injected sandstone during the imbibition stage. Electrical resistivity and P-wave velocity measurements acquired during the drainage and imbibition stages were employed to evaluate CO2 saturations (SCO2) based on the resistivity index and the Gassmann fluid-substitution equations, respectively. Comparing estimated values for SCO2 saturation against those from volume-derived SCO2, based on analysis on injected and drained fluid volumes in the drainage process, we conclude that Gassmann‐Brie and resistivity index are suitable for the evaluation based on P-wave velocity and electrical resistivity, respectively. Rt-based estimation properly tracks the variation in SCO2 even when SCO2 is large (>0.15), while Vp-based estimation is sensitive to the variation in SCO2 when SCO2 is small ( 0.1), while properly estimating SCO2 when SCO2 is small (<0.1). Monitoring the CO2 imbibition process confirms residual CO2 saturation within the sample.

Elastic anisotropy and pore space geometry of schlieren granite: direct 3-D measurements at high confining pressure combined with microfabric analysis

Pore space geometry of granitic rocks and its evolution with depth are key factors in large-scale seismics or in projects of enhanced geothermal systems or of deep hazardous waste repositories. In this study, we studied macroscopically anisotropic schlieren-bearing granite by experimental P-wave velocity (V-P) measurements on spherical sample in 132 directions at seven different confining pressures in the range 0.1-400 MPa. In order to discriminate the phenomena affecting the rock elastic properties we analysed the orientation of microcracks and of grain boundaries and we measured the anisotropy of magnetic susceptibility of the rock. Three sets of microcracks were defined, with two of them linked to the massif exfoliation process and one to cooling contraction of the massif. During pressurization the measured mean V-P and V-P anisotropy degree at ambient pressure and at highest confinement (400 MPa) yielded 3.3 km s(-1) and 24 per cent, and 6.2 km s(-1) and 3 per cent, respectively. The associated V-P anisotropy pattern was transversely isotropic and governed by the schlieren, with a minimum V-P direction perpendicular to them and a girdle of high V-P directions parallel to them. The highest change in V-P was observed between 0.1 and 10 MPa, suggesting a significant closure of porosity below depths of 500 m. Change of the V-P anisotropy pattern to orthorhombic together with increase of mean V-P and V-P anisotropy degree during depressurization was attributed to inelastic response of one of the sets of microcracks to the loading-unloading cycle.

Evaluation of geo-mechanical properties of very weak and weak rock materials by using non-destructive techniques: Ultrasonic pulse velocity measurements and reflectance spectroscopy

The main purpose of this study is to evaluate the geo-mechanical properties of very weak and weak rock materials by using ultrasonic pulse velocity measurements and considering specifically detailed mineralogical compositions. For the purpose, P-wave velocity (Vp) measurements of 66 core samples of the sedimentary rocks including claystones and mudstones collected from Firuzkoy area of Istanbul (Turkey) were carried out. Unconfined Compressive Strength (UCS) tests were then conducted. The axial deformations recorded during the UCS tests were also evaluated and the elastic moduli of the rock materials (Ei) were calculated. Statistical relations were investigated between the values of P-wave velocity measurements and the UCS and Ei. In order to evaluate the effects of detailed mineralogical compositions on the prediction performances of the empirical equations Vp-UCS and Vp-Ei, the reflectance spectroscopy was introduced. 1035 spectral measurements were taken from smooth and fresh surfaces of the failed core samples. Different genetic rock types were defined according to crystal field effect and charge transfer absorptions of transition elements, and water and OH vibrational spectral diagnostics. The statistical relations were reinvestigated, and the individual empirical equations were reproduced for each genetic rock type. The mean values of the multiple coefficients of correlations (R) were obtained to be 0.904 and 0.916 for the equations of Vp-UCS and Vp-Ei. Considering the maximum values of R, the increment rates for the values of the explained variances reach up to 14.3% and 13.5% for the equations, respectively. Additionally, according to the results of the analysis of variance (ANOVA) evaluations, the empirical equations of Vp-UCS and Vp-Ei reproduced for each genetic rock type were found to be statistically significant at the significance level of 0.05. As a consequence, the non-destructive techniques Vp measurements and reflectance spectroscopy could be efficiently used together for the evaluation of the geo-mechanical properties of very weak and weak rock materials in particular.

Geotechnical Influence on the Acoustic Properties of Marine Sediments of the Santos Basin, Brazil

There are several problems associated with core location and sediment deformation during the coring procedure. Geophysical investigation of the seafloor using acoustic systems, such as high-resolution seismic and single-beam sediment classification, provides a very cost-effective evaluation on the distribution of sedimentary environments. The present study investigates the relationship between acoustic impedance and geotechnical properties of shallow marine sediments from the Santos Basin, Brazil. A total of eight cores from different geological settings were collected and measurements of P-wave velocity (Vp), gamma density, mean grain size, void ratio, water content and shear strength were conducted. The results show that, despite different trends according to the sedimentary environment, the acoustic impedance correlates very well with all geotechnical parameters analyzed.

Difference in acoustic properties at seismogenic fault along a subduction interface: Application to estimation of effective pressure and fluid pressure ratio

Fluid pressure along subduction plate boundaries plays a role in seismogenesis and tsunami genesis because it is strongly related to the physical properties of faults. In this study, we conducted P-wave velocity (Vp) and S-wave velocity (Vs) measurements for the hanging wall and footwall of a fossil subduction interface with pseudotachylyte located at the northern edge of the Mugi mélange in the Cretaceous Shimanto Belt, Shikoku, southwest Japan. This area corresponds to the depth of the shallow seismogenic zone in the transition zone between the inner and outer wedges. By combining the acoustic properties with parameters obtained from Amplitude Variation with Offset (AVO) analysis on the Nankai seismic profile, we estimated the fluid pressure at the seismogenic fault. The Mugi mélanges are composed of shale matrices and are juxtaposed with the coherent unit of the Hiwasa formation in the north, which is composed mainly of sandstone. We collected 5 sandstone samples from the hanging wall (Hiwasa formation) and 4 mudstone samples from the footwall (Mugi mélange). We conducted velocity measurements while controlling both the fluid pressure and confining pressure by using two pumps. The effective pressure in each measurement ranged from 5 to 65 MPa with intervals of 5 MPa. The Vp and Vs of sandstone increase exponentially with effective pressure from ~ 4500 to ~ 5000 m/s and ~ 2500 to ~ 3000 m/s, respectively. The Vp and Vs of the mudstone also increased exponentially from ~ 4100 to ~ 4500 m/s and ~ 1900 to ~ 2200 m/s, respectively. We used AVO parameters along the décollement based upon a seismic profile of the Nankai trough, which is off Muroto 40–45 km landward from the trench axis, corresponding to approximately 66 MPa of effective pressure under a hydrostatic condition. By combining the velocities obtained from this study and the AVO parameters derived from the Muroto seismic data, we estimate the mean effective pressures for the hanging wall and the footwall as approximately 10–20 MPa and 8–10 MPa, respectively. The normalized fluid pressure ratios for the hanging wall and the footwall correspond to approximately 0.82–0.91 and 0.91–0.93, respectively. This high fluid pressure indicates a very low effective friction coefficient along the décollement in the transition zone, possibly causing a rupture to propagate to the shallower outer wedge and thus generating a large tsunami. • Vp and Vs were measured from hanging-wall and footwall at a fossil seismogenic décollement. • Very high fluid pressure ratio was estimated using seismic data and obtained properties. • The target depth was at transition zone, deeper than that of previous works.

Microstructural Development of Hydrating Portland Cement Paste at Early Ages Investigated with Non-destructive Methods and Numerical Simulation

Microstructure development of hydrating cement paste at early ages is not only an indicator of the reactivity of cement, but also a factor on the workability of fresh concrete. In this study, the microstructure development of hydrating cement paste at early ages is investigated with non-destructive methods including ultrasound P-wave propagation velocity measurement and non-contact electric resistivity tests, together with conventional needle penetration depth and calorimetry tests. The hydration process and microstructural development of the cement paste is modeled with the three-dimensional computer model CEMHYD3D. Evolution of microstructural parameters including the volumetric fraction of phases and their percolation status are analyzed by using the results of the numerical simulation. Microstructural mechanisms of the two non-destructive techniques (ultrasound pulse propagation and electric resistivity measurements) are discussed. The main findings of this study are that the velocity of ultrasound P-wave propagation in hydrating cement paste is a function of the propagation routes in the material and inter-particle forces. The electric resistivity is controlled by the ionic concentrations in the pore solution during the early hours and later by the connectivity of pores. A model for the development of ultrasound P-wave propagation velocity is also proposed.

花崗岩のP波速度分布とDSCA法から求めたクラックパラメータの関係

In general, granite has anisotropy due to the preferred orientation of pre-existing micro-cracks. It is possible to obtain the information of the preferred orientation of micro-cracks by the measurement of the P-wave velocity. Therefore, by measuring P-wave velocity in various directions, we can obtain the information of three-dimensional distribution of micro-cracks in granite. Assuming that the three-dimensional distribution of micro-cracks in granite was caused by the stress release during coring, it can be possible to assess the stress state at the location of coring in the underground considering the relationship between three-dimensional distribution of P-wave velocity and microcracks. Differential Strain Curve Analysis (DSCA) is one of the methods to assess the stress state in the underground using rock core samples based on the initiation of micro-cracks due to the stress release. Therefore, if the three-dimensional distribution of P-wave velocity can be related to the orientation of micro-cracks determined by DSCA, the stress state in the underground can be evaluate from the measurement of P-wave velocity. In this study, by conducting both P-wave velocity measurements in various directions with a polyhedral specimen and DSCA using granite samples obtained from the same location, the relationship between the three-dimensional distribution of P-wave velocity and that of the crack parameter determined from DSCA was investigated. In addition, we considered the possibility to assess the stress state in the underground from P-wave velocity measurement. From the above measurements, a negative correlation between the P-wave velocity and the crack parameter from DSCA was observed for granite. Additionally, by using the value of the P-wave velocity which is corresponding to the crack-free granite rock, we could show the possibility to assess the stress state in the underground.

Determination of Thermal Conductivity and Porosity of Building Stone from Ultrasonic Velocity Measurements

Ultrasonic velocity measurement, a non-destructive and easy method to apply in both field and laboratory conditions, has increasingly been conducted to determine the physical properties of rock materials. This paper presents an experimental study of the measurement of P-wave velocity, thermal conductivity and porosity of several types of sedimentary, metamorphic, and magmatic rocks. The aim of this study is to predict the rocks properties including their thermal conductivity and porosity using P-wave velocity. For this purpose, the physical properties are determined in the laboratory to obtain correlations between P-wave velocity and physical properties. Consequently, good linear relationships are found between all the determined physical properties and the P-wave velocity measurements.