Elasticity of partially saturated frozen sand

Geophysics ◽  
1996 ◽  
Vol 61 (1) ◽  
pp. 288-293 ◽  
Author(s):  
Maureen Jacoby ◽  
Jack Dvorkin ◽  
Xingzhou Liu
Keyword(s):  
Surface Sediments ◽  
Seasonal Temperature ◽  
Frozen Ground ◽  
Near Surface ◽  
Seismic Profiling ◽  
Partially Saturated ◽  
Vertical Seismic Profiling ◽  
Frozen Sand ◽  
Scientific Goal ◽  
Seasonal Thawing

Seasonal thawing and freezing of near‐surface sediments significantly affect the interpretation of seismic reflection surveys and vertical seismic profiling, as well as activity on the surface. Permafrost covers much of the Earth’s colder regions and is also subject to periodic thawing and freezing. The significance of the regions with large seasonal temperature variations for exploration and engineering activities makes understanding the elasticity of frozen ground an important practical and scientific goal.

GROUND AND AIRBORNE RESISTIVITY SURVEYS OF PERMAFROST NEAR FAIRBANKS, ALASKA

Geophysics ◽  
1975 ◽  
Vol 40 (4) ◽  
pp. 641-656 ◽  
Author(s):  
P. Hoekstra ◽  
P. V. Sellmann ◽  
A. Delaney
Keyword(s):  
Surface Impedance ◽  
Apparent Resistivity ◽  
Surface Sediments ◽  
Impedance Measurement ◽  
Impedance Method ◽  
Frozen Ground ◽  
Near Surface ◽  
Fine Grained ◽  
Ground Conditions ◽  
Geotechnical Information

In permafrost regions investigations for such geotechnical endeavors as route selection for roads and pipelines and site investigations for buildings and dam construction often require that a careful assessment be made of the presence or absence of frozen ground, of the ice content of frozen ground, and of the depth of frozen ground. In the vicinity of Fairbanks, Alaska, where the permafrost is discontinuous, ground and airborne methods of mapping electrical resistivity using radiowaves were tested as means of delineating permafrost. When the resistivity maps are compared with surficial geological data, the following conclusions are reached: (1) In areas of fine‐grained sediments, where the near surface sediments are relatively uniform, VLF resistivity delineates permafrost. (2) In areas where surface sediments vary widely (flood plains), VLF resistivity shows little information on permafrost conditions but can provide other important geotechnical information, such as, depth to bedrock, surface soil type, and layering. Comparison of the apparent resistivity derived from a surface impedance measurement at VLF on the ground with the apparent resistivity derived from an airborne measurement of wavetilt shows that the regional trends in the data agree, but the surface impedance measurements show much more local detail in ground conditions. When the surface layers are also frozen, the surface impedance method of measuring ground resistivity was found to have distinct advantages over conventional galvanic methods in terms of production and problems associated with probe contact resistance.

Rapid map and inversion of P-SV waves

Geophysics ◽  
1991 ◽  
Vol 56 (6) ◽  
pp. 859-862 ◽  
Author(s):  
Robert R. Stewart
Keyword(s):  
Spatial Resolution ◽  
Seismic Data ◽  
P Wave ◽  
Rock Properties ◽  
Low Velocity ◽  
P Waves ◽  
Near Surface ◽  
Seismic Profiling ◽  
Vertical Seismic Profiling ◽  
And Inversion

Multicomponent seismic recordings are currently being analyzed in an attempt to improve conventional P‐wave sections and to find and use rock properties associated with shear waves (e.g. Dohr, 1985; Danbom and Dominico, 1986). Mode‐converted (P-SV) waves hold a special interest for several reasons: They are generated by conventional P‐wave sources and have only a one‐way travel path as a shear wave through the typically low velocity and attenuative near surface. For a given frequency, they will have a shorter wavelength than the original P wave, and thus offer higher spatial resolution; this has been observed in several vertical seismic profiling (VSP) cases (e.g., Geis et al., 1990). However, for surface seismic data, converted waves are often found to be of lower frequency than P-P waves (e.g., Eaton et al., 1991).

scholarly journals Time-lapse imaging of CO2 migration within near-surface sediments during a controlled sub-seabed release experiment

2021 ◽  
Vol 109 ◽  
pp. 103363
Author(s):  
Ben Roche ◽  
Jonathan M. Bull ◽  
Hector Marin-Moreno ◽  
Timothy G. Leighton ◽  
Ismael H. Falcon-Suarez ◽  
...  
Keyword(s):  
Surface Sediments ◽  
Time Lapse ◽  
Near Surface ◽  
Release Experiment ◽  
Time Lapse Imaging

Creep Parameters for Pile Settlement Equations

1989 ◽  
Vol 111 (4) ◽  
pp. 258-263
Author(s):  
D. Stelzer ◽  
O. B. Andersland
Keyword(s):  
Static Load ◽  
Experimental Tests ◽  
Sand Particle ◽  
Shear Stresses ◽  
Frozen Ground ◽  
Creep Equation ◽  
Frozen Sand ◽  
Pile Settlement ◽  
Ice Content ◽  
Friction Pile

Friction pile settlement in frozen ground is tyically predicted on the basis of a creep equation relating shear stresses at the soil/pile interface to pile displacement rates. Creep parameters are used to characterize soil type, soil/ice structure, temperature, and loading conditions. Experimental tests involving model steel piles embedded in frozen sand provided data showing that change in a given test variable can alter the numerical value for some of the creep parameters. The test variables included static, incremental, and dynamic loading; pile surface roughness; soil ice content; and sand particle size. Changes observed included the apparent effect on creep rate when a small dynamic load was superimposed on the static load. A tabulation of observed creep parameter changes is included.

Fracture detection using P-wave and S-wave vertical seismic profiling at The Geysers

Geophysics ◽  
1988 ◽  
Vol 53 (1) ◽  
pp. 76-84 ◽  
Author(s):  
E. L. Majer ◽  
T. V. McEvilly ◽  
F. S. Eastwood ◽  
L. R. Myer
Keyword(s):  
Fractured Rock ◽  
Geothermal Field ◽  
P Wave ◽  
Velocity Variation ◽  
Fracture Detection ◽  
S Wave ◽  
Fracture Geometry ◽  
Seismic Profiling ◽  
Vertical Seismic Profiling ◽  
The Geysers

In a pilot vertical seismic profiling study, P-wave and cross‐polarized S-wave vibrators were used to investigate the potential utility of shear‐wave anisotropy measurements in characterizing a fractured rock mass. The caprock at The Geysers geothermal field was found to exhibit about an 11 percent velocity variation between SH-waves and SV-waves generated by rotating the S-wave vibrator orientation to two orthogonal polarizations for each survey level in the well. The effect is generally consistent with the equivalent anisotropy expected from the known fracture geometry.

scholarly journals Mapping the Distribution of Buried Glacier Ice – An Example From Lago Delle Locce, Monte Rosa, Italian Alps

1986 ◽  
Vol 8 ◽  
pp. 78-81 ◽  
Author(s):  
W. Haeberli ◽  
F. Epifani
Keyword(s):  
Snow Cover ◽  
Seismic Refraction ◽  
Italian Alps ◽  
Frozen Ground ◽  
Near Surface ◽  
Winter Snow ◽  
Glacier Ice ◽  
Geoelectrical Resistivity ◽  
Monte Rosa

Techniques for mapping the distribution of buried glacier ice are discussed and the results, from a study carried out within the framework of flood protection work in the Italian Alps, are presented. Bottom temperatures of the winter snow cover (BTS) primarily indicate the heat flow conditions in the underlying ground and mainly depend on the presence or absence of an ice layer beneath the surface. Determination of BTS values is therefore an inexpensive method for quickly mapping the near-surface underground ice in areas where there is 1 m or more of winter snow cover. At greater depths, and/or when more detail is required, geoelectrical resistivity soundings and seismic refraction soundings are most commonly used to investigate underground ice. A combination of the two sounding techniques allows the vertical extent and the main characteristics (frozen ground, dead glacier ice) to be determined in at least a semi-quantitative way. Complications mainly arise from irregularity in the horizontal extension of the studied underground ice bodies, and they may have to be overcome by expensive core drillings and borehole measurements. Widespread occurrence of buried glacier ice was observed in morainic deposits, surrounding an ice-dammed lake near Macugnaga, Italy.

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