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5th EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems
- Conference date: 26 Apr 1992 - 29 Apr 1992
- Location: Oakbrook, Illinois, USA
- Published: 26 April 1992
1 - 20 of 40 results
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Marine Seismic-Reflection Profiling To Define Hydrogeologic Continuity At Camp Lejeune, North Carolina
Authors Alex P. Cardinell and Steven A. BergContinuous marine seismic-reflection-profiling data were correlated with
land-based borehole geophysical and lithologic data to define the hydrogeologic
framework of Camp Lejeune Marine Corps Base in part of the Coastal Plain
Province of southeastern North Carolina. Marine seismic profiling was
particularly useful at Camp Lejeune because 25 percent of the study area is
covered by the New River estuary system.
A medium-power, wide-frequency seismic system was used to collect
continuous single-channel, shallow-marine seismic-reflection-profiling data for
more than 100 miles of transects across the estuary. Positioning of the boat
equipped with seismic instruments was controlled by an onboard integrated
navigation system; LORAN C and Global Positioning Systems' were integrated to
continuously plot boat position.
Onshore borehole geophysical and lithologic data were compared with
seismic data. A borehole acoustic-velocity log was used to generate an average
acoustic-velocity curve for the sediment, which was then used to convert the
seismic travel time to depth. The acoustic-velocity, single-point resistance,
and gamma-ray log data were adjusted for altitude and dip and correlated with
the seismic data.
Hydrogeologic sections constructed using these correlations show that the
combined thickness of the surficial, Castle Hayne, and Beaufort aquifers ranges
from approximately 200 feet at the western edge of the study area to approximately
490 feet at the eastern edge. Three sections of buried river channel
have been identified within the Castle Hayne aquifer underlying the New River
by seismic-reflection-profiling data. One of these channels has been correlated
with well-log data. Buried channels, if filled with permeable material,
can function as conduits for ground-water flow, thereby facilitating movement
of contaminants from land surface, or saltwater migration from the estuary to
supply wells.
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Identification Of A Multiaquifer Ground-Water Crosscontamination Problem In The Stockton Forjmation By Use Of Borehole Geophysical Methods, Hatboro, Pennsylvania
Authors Ronald A. Sloto, Paola Macchiaroli and Michael T. TowleAbandoned industrial and public supply wells and improperly constructed monitoring wells open to
multiple water-bearing zones in the Triassic Stockton Formation in Pennsylvania short circuit the
ground-water-flow system and are conduits for contaminant transport. Borehole geophysical methods
were used to construct a three-dimensional lithostratigraphic model, identify fluid-producing and
fluid-receiving zones (fractures), measure vertical borehole-fluid movement, and serve as the basis for
proper design and construction of monitoring wells. Natural-gamma, single-point-resistance, caliper,
fluid-temperature, and fluid-resistivity logs were run in 16 boreholes 149 to 470 feet deep.
The lithostratigraphic model of the dipping sedimentary rocks of the Stockton Formation primarily is
based on natural-gamma, single-point-resistance, and caliper logs. Geophysical logs from one borehole
were compared to a 200-foot-long rock core from that borehole to determine the relative response
of the geophysical logs to lithology. This comparison was used as the basis for litbologic interpretation
of the geophysical logs of the other boreholes. The interpreted lithostratigraphy correlates well from
borehole to borehole.
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Subsurface Charact!Bization Using Integrated Geophysical Methods: A Case History
Authors John J. Nicholl and Kathryn CainA geotechnical assessment was made of the Northwest Boundary Containment System (NWBCS) at the Rocky
Mountain Arsenal near Denver, Colorado. This assessment was conducted to support the Interim Response
Action (IRA) Alternative Assessment addressing the NWBCS Long-Term Improvements IRA, and was designed
to evaluate the present groundwater and recharge system, assess potential contaminant bypass of the system, and
identify remediation requirements of the system. Geophysical techniques were used as part of the geotechnical
assessment. Three surface geophysical techniques were used including seismic refraction, electromagnetics (EM),
and electrical resistivity soundings. Additionally, limited downhole geophysical logging was conducted for
correlation with surface geophysical data. The field program included approximately 32,000 linear feet of seismic
refraction data, 52,000 linear feet of EM data, 13 resistivity soundings using the Schlumberger electrode array,
and downhole geophysical logging in two boreholes. Seismic refraction data were combined with lithologic log
data to produce a map of the top of a sand and gravel unit that overlies the bedrock Denver Formation. Data
from the EM survey were combined with lithologic log data to produce a map of the top of the Denver
Formation. The resistivity and downhole results were used to augment the seismic and EM data. The results
of the geophysical investigation provided additional information for defining the location and geometry of
paleochannels and aided characterization of the interface between the Denver Formation and overlying alluvium.
EM results were particularly useful in providing information about the paleotopography of the Denver Formation
in areas where borehole data were sparse, allowing the detection of several previously unknown small
paleochannels in the Northwest Boundary area. Geophysical results allowed further refinement of the main
paleochannel and its orientation at the southwest end of the boundary system and confirmed the presence of a
suspected paleochamtel northeast of the system. All geophysical results, along with drilhng data, were then
incorporated into the hydrogeologic and contaminant transport models of the boundary system to aid evaluation
of its present and future effectiveness.
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Proper Appllcatlon Of Borehole Geophysical Techniques To The Evaluation Of A Carbonate Aquifer: A Case Histor
More LessThis paper documents a petrographic and petrophysical analysis of a water
supply test hole drilled in southwest Texas. The six inch hole penetrated the lower
Cretaceous Georgetown and Kiamichi Formations to a depth of 520 feet.
Initial analysis of the hole was ambiguous. Density and sonic porosities
were as high as 22% and 30%, respectively. However, an air-lift test of the well
produced only 35 gallons of water per minute. Further analysis of the well was
deemed necessary.
A petrographic examination of the drill cuttings was conducted to resolve
the discrepancy between the high porosity and low water production rates and to
determine if water production could be enhanced by acidizing or fracturing the
well. The logs were also analyzed in an attempt to resolve the discrepancy
between the density and sonic porosity values. Recommendations were made
regarding the most effective methods for evaluating subsequent wells.
Petrographic analysis of the cuttings revealed that the rock is a slightly
shaly, fossiliferous limestone with isolated moldic and micro-intergranular porosity.
While total porosity is high, effective porosity is very low. Neither fracturing nor
acidizing the well would significantly increase permeability and specific yield.
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Hydrogeologic Parameters Of Reclaimed Coal Strip Mines From Borehole Geophysical Surveys
Authors D.M. Diodato and R.R. ParizekTwo nuclear methods were used to quantify hydrogeologic parameters in the
unsaturated zone of a reclaimed and revegetated coal strip mine spoil pile in Clarion,
Pennsylvania. These investigations were part of an ongoing acid mine drainage
abatement demonstration project. Quantitative descriptions of physical properties
affecting fluid flow in deep strip mine spoil piles were previously unavailable. In
order to quantify moisture content, bulk density, porosity, and unsaturated hydraulic
conductivity, six 6.4 m seamless aluminum neutron access tubes were installed in
boreholes at the site. These were probed with Am-Be (neutron) and Cs-137 (gammagamma)
probes on 7 different dates.
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Magnetqmetry As A Tool To Map Subsurface Conditions In An Abandoned Iron Ore Mining District In New Jersey
Authors K.K. Cohen, N.N. Moebs and M.A. TrevitsAbandoned underground coal and metal mines present a number of environmental risks to communities.
Ground subsidence resulting from the collapse of mine workings ranks high among these risks.
Collapse or subsidence of the ground surface can result in safety hazards to residents, property
damage, and loss of land use. Field methods that provide geotechnical information about the
underground mine configuration and stability of the mine overburden are needed. In the past, a number
of site specific geophysical tools such as seismic techniques, gravity surveys, and electromagnetic
methods have been used in an attempt to acquire subsurface mine and overburden rock mass
information. This study investigates the use of magnetic mapping as a tool to delineate shafts and
underground workings responsible for ground instability in an abandoned metal-mining district of New Jersey.
The Township of Mine Hill, New Jersey has been plagued by subsidence for decades due to
unpredictable failure of portions of more than 20 abandoned iron ore mines which riddle the subsurface
of this community. Historical records indicate that mining started during the early 1700’s and continued
until 1966 with the closing of the last mine. Ore production was from high grade magnetite deposits
intruded into Precambrian crystalline rocks. Due to the high magnetic susceptibility contrast between
the ore and country rock, and a rather uniform orientation of the deposits, a unique opportunity was
available to delineate the abandoned mine workings using ground magnetic surveys.
Several abandoned mines in the Township of Mine Hill were selected for investigation. Historical mine
maps were used to design a gridded station array, and a proton precession magnetometer was used to
conduct a ground survey over each mine. Modeled anomalies computed from historical mine maps and
other available subsurface information were compared to anomalies observed in the field. Results
suggest that magnetometry is useful in delineating the condition and location of mine workings. This
information could be useful for subsequent remediation and land use planning for undermined areas.
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Time Domain Electromagnetic Measurements To Determine Water Quality In Tee Floridan Aquifer
Authors Pieter Hoekstra, Jim Hild and David TothThe Floridan aquifer system is one of the most productive
aquifers in the world. This aquifer system underlies an area of
about 100,000 square miles in southern Alabama, south-eastern
Georgia, southern South Carolina, and all of Florida. The
Floridan aquifer system provides water for several large cities,
including Savannah and Brunswick in Georgia; and Jacksonville,
Tallahassee, Orlando, and St. Petersburg in Florida. Locally,
the Floridan is intensively pumped for industrial and irrigation
supplies. During 1985, an average of about 3 billion gallons per
day of fresh water was withdrawn from the Floridan for all
purposes (Miller, 1990). Despite the huge volumes of water that
are being withdrawn from the aquifer system, water levels have
not declined greatly except locally where pumpage is concentrated.
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Continuous Electrical Resistivity Surveys Along The Lake Michigan And Green Bay Coastlines Of Wisconsin
More LessElectrical resistivity depth soundings were obtained at 15
meter intervals along the entire Lake Michigan and Green Bay
shorelines of Wisconsin using a towed resistivity system
developed for this purpose. The electrical longitudinal
conductance for the bottom sediments, derived from the sounding
data, was empirically related to hydraulic leakance. The
hydraulic leakance was obtained from the direct measurement at
selected locations of bottom sediment seepage. The empirically
derived relationship was combined with ground water flow models
to estimate ground water flux on a nearly continuous basis along
the shorelines. The resulting flux estimates spatially vary from
-15 cubic meters per day per kilometer to 560 cubic meters per
day per kilometer of shoreline. The average input to Lake
Michigan was estimated to be 480 cubic meters per day per
kilometer of shoreline and this estimate is within the range
exhibited by previous estimates.
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Use Of Ground-Penetrating Radar And Continuous Seismic-Reflection Profiling On Surface-Water Bodies In Environmental And Engineering Studies
By F.P. HaeniGround-penetrating radar (GPR) and continuous seismic-reflection
profiling (CSP) on shallow rivers, lakes, and ponds are efficient and
economical ways of obtaining subsurface hydrologic and geologic information
for environmental and engineering studies. These methods are similar in
that they produce continuous subsurface profiles, are easy to use, and the
records can be straightforward to interpret. They are dissimilar in that GPR
cannot penetrate electrically conductive water or subsurface sediments, and
CSP usually cannot operate in water less than 5 ft (feet) deep.
GPR records collected on a lake in New Hampshire have been interpreted
to estimate the depth to bedrock and to evaluate the grain-size
characteristics of the underlying stratified drift at the lakeshore
boundary. In a pond in Massachusetts, CSP and GPR were used to determine
the depth to bedrock and the grain-size characteristics of the subbottom
materials in part of the pond. Water-column multiple reflections, depth and
conductivity of water and subsurface materials, and diffractions degraded
the quality of the GPR records.
CSP records collected in the Connecticut River near Hartford,
Connecticut were used to estimate the depth of till and bedrock interfaces
and to evaluate the grain-size characteristics of subsurface materials.
Interpreted CSP records also can indicate bedding planes within consolidated
rock units. Water-column multiple reflections and very shallow water
degraded the quality of the CSP records.
GPR and CSP methods have been used to delineate infilled scour holes
near bridge piers. Scour holes that have been filled with up to 8 ft of
loose sand have been mapped during engineering-scour studies near a bridge
in Connecticut.
Because GPR and CSP operate on different principles, the two
geophysical methods complement each other. Depending on the required depth
of penetration and the degree of resolution needed, one or both of these
methods can be used to acquire accurate and reliable subsurface hydrologic
and geologic information critical to environmental and engineering studies.
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Use Of Marine-Seismic Profiling To Study Ground-Water Contamination At Aberdeen Proving Ground, Maryland
More LessContinuous high-frequency marine-seismic profiling was used to define the extent of geologic units offshore
of J-Field, Aberdeen Proving Ground, Maryland, during March and April of 1988. J-Field was used by the U.S. Army
for disposal of chemical warfare agents, munitions, and organic solvents from the early 1920’s through the 1970’s. A
major concern at this site has been the discharge of contaminated ground water into offshore areas and eventually into
the Chesapeake Bay. A 150-foot-deep paleochannel containing Pleistocene fluvial and estuarine sediments was
identified from onshore geologic borings. The paleochannel sediments consist of three geologic units: a basal unit of
gravel and sand, a middle unit of silty clay, and an overlying unit of interbedded clay and sand. The seismic profiles
identified the extent of these units and were used to map them in offshore areas. An accurate knowledge of the
distribution of the geologic units in onshore and offshore areas is important to the investigation because the coarsegrained
paleochannel sediments could provide a preferential flow path for hazardous wastes and the fine-grained
sediments could impede their movement. The seismic data were also used in a ground-water-flow model of the study
area to define the boundary conditions and to aid in the design of the finite-difference grid.
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A Waterborne Geophysical Technique For Assisting Proposed Dredging Projects
Authors Keith J. Sjostrom, Robert F. Ballard Jr. and Richard G. McGeeEach year, the U.S. Army Corps of Engineers spends millions of dollars
world-wide on river and harbor maintenance and ship channel realignment
projects. Currently, the Corps relies on drilling and laboratory testing
programs to assess marine sediments in terms of material type, density, and
thickness for the purposes of characterizing proposed dredging sites. But
sampling and coring programs are costly and provide only discontinuous information
about the material characteristics.
In 1988, the Corps of Engineers launched a major research and development
initiative called the Dredging Research Program (DRP) directed toward
developing new or better technologies to improve subbottom sediment characterization,
increase dredging efficiency, and reduce the overall costs of dredging
and sampling operations. The U.S. Army Engineer Waterways Experiment
Station (WES) heads this initiative. Through the combined effort of the
Hydraulics Laboratory and Geotechnical Laboratory, the focus of one of its
work units is to remotely and efficiently determine the characteristics of
subbottom marine sediments using acoustic impedance information together with
limited drilling.
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The Model Se880 Sonar Image And Record Enhancement System
Authors P.A. Baxter and R.J. MillsThe Sonar Image and Record Enhancement project, a two phase collaborative research and
development project, was awarded and part funded by the UK Department of Trade and
Industry to GeoAcoustics Limited, formerly Ferranti ORE Limited. Heriot Watt University
and British Geological Survey were subcontracted to the research. Professor Larry Mayer,
a marine geologist from Dalhousie University, Halifax, Canada is a consultant to this group.
In addition several institutes and research centres have provided valuable feedback of
information in using the system that has resulted in improved data acquisition.
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Azimuthal Resistivity Techniquib And Tke Directional Variations Of Hydraulic Conductivity In Glacial Sediments
Authors William A. Sauck and Scott M. ZabikField and analog tank model studies were done to examine the response of various
electrode arrays and to try to develop an optimum field technique. Field studies were on
fractured tills and on glacial outwash fan deposits. In the latter, anisotropy in electrical
resistivity (and by inference, the hydraulic conductivity) is a result of primary depositional
structures, principally the stacked braided stream channels. Schlumberger, Wenner, Pole-
Dipole, Pole-Pole and other modified arrays were tested. Various ways of normalizing and
plotting the results were developed. All arrays showed clear anisotropy effects and there is no
single best array or field technique which is most sensitive to anisotropy. Choice of technique
depends on the size of the field crew, access or ease of installing remote electrodes, and size
of the field or open space. Clearly, a Vertical Electrical Sounding (VES) must first be done
near a control well in the area to establish the appropriate electrode spacings for investigating
the depth range of interest. Field studies at one outwash fan site concentrated on vertical
variations, where. 12 azimuthal plots were made for a full range of current electrode halfspacings
of 1 to 100 m about one central point. A second phase of the work at this site studied
lateral variations, k the center point was moved 180 m laterally to obtain a measure of the
local geologic “noise” or variability. The lateral variability was less for larger electrode
spacings, as these sampled and averaged over a much larger volume.
The tank modeling was done to study the effects of the distance laterally and vertically
from the top of the fracture(s) to the array center point. The azimuthal apparent resistivity
diagram changed significantly with lateral position relative to a single “fracture”. For the
application of azimuthal resistivity techniques to fracture and joint investigations, a number of
azimuthal surveys at closely spaced points must be done to remove ambiguities caused by
unknown fracture spacing, and by unknown lateral distance to the nearest fracture. For multisheet
models, increasing the thickness of a homogeneous overburden eliminated the “Paradox
of Anisotropy” effect and rotated the ellipse 90 degrees.
Azimuthal surveys should prove to be useful at sites where detailed ground water flow
models are required, as resistivity azimuthal effects of 10 - 40% are common and presumably
the directional hydraulic conductivity variations may have similar magnitudes. The
disadvantage of the technique is that it is cumbersome and requires a large circular open space
free of interfering conductors; thus it is not applicable at many sites. The information
provided, however, is unattainable by any other means within reasonable economic limits.
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Refraction Seismic Survl3Y Of Some Thick Till In Southeast Alaska
More LessA geotechnical investigation was conducted in a small, steep, tidewater glaciated valley
in southeastern Alaska. The geotechnical drilling program encountered unanticipated
overburden thicknesses in excess of 100 feet on one side of the valley. A refraction seismic
survey was conducted to augment the geotechnical program. Interesting aspects of the
geophysical survey included the remote location; logistics to and at the tent camp; limited
helicopter use; the steep and rugged forested terrain; the availability of drill hole information;
the combination of doing shallow and deep looking surveys; the deep depth of investigation
which required long lines, long off-end shots, and large explosive charges; and the snow cover
and the short amount of daylight during the early winter survey.
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Combined Seismic Reflection And Refraction Methods In Coastal Engineering Site Investigation
Authors Robert J. McDonald, Peter J. Brabham and Michael BrooksA combined seismic reflection and refraction approach to coastal site investigation is
described using case studies at two sites in South Wales, UK. The land-based surveys, using the
BISON 9024 seismograph, were carried out in the intertidal zone with a target depth of 4m to
40m below surface.
The reflection data show a dominant frequency of 550Hz which, coupled with seismic
velocities averaging 16OOm/s, produces a quater-wavelength vertical resolution of 0.7m. Results
have imaged local rockhead and lithological boundaries in the overlying unconsolidated
sediments. Comparisons of hammer, buffalo gun and detonator sources are shown and their
relative suitability for use in the intertidal zone is discussed.
In interpreting shallow reflection data the requirement of rockhead depth control from
seismic refraction surveying and/or boreholes is emphasised. This is of particular importance if
the bedrock is deeply weathered and has a lower acoustic impedance contrast with overlying
sediments than other reflecting interfaces. Combined refraction and reflection surveys can
provide detailed information on rockhead depth and overlying sediment geometries. This
information can be valuable to the coastal engineer in both the design and location of man-made
structures.
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Studies In P-Wave And S-Wave Seismics
Authors C. Richard Bates, David Phillips and James HildThe technique of compressional (P) wave refraction is
routinely used in geotechnical and hydrogeological surveys.
Developments over the last 10 years in field procedures and
methods of data analysis have greatly increased the utility of
this technique in mapping targets in the shallow environment.
Nonetheless, two problems associated with hidden layers are often
cited as serious shortcomings with the technique, namely mapping
the top of the hidden layer and mapping boundaries below the
hidden layer. If a hidden layer is not identified in the data,
the errors in depth calculations can be significant. Lankston
(1989) has demonstrated the use of the general reciprocal method
(GM) for recognizing a hidden layer and mapping of boundaries
below the layer. Once recognized, the errors in depth
calculations are reduced but are still greater than. for problems
where a hidden layer does not exist. This reason is often used
to justify more costly P-wave reflection surveys.
While not routinely applied in shallow investigations,
horizontally polarized shear waves can yield additional
information. Shear (S) wave velocity is largely dependent on the
shear modulus or stiffness of a material and is virtually
unaffected by degree of saturation. As a result of the different
nature of S-wave propagation, S-waves may often show boundaries
not seen in P-wave surveys and equally the P-wave may show
boundaries S-waves do not.
The combined use of both P and S-wave seismics are described
for two site surveys. Lithology logs were available for both
sites and the seismics investigation formed part of a more
comprehensive geophysical feasibility study.
The hidden layer problem is often encountered in shallow
unconsolidated sediment/bedrock surveys where "velocity
inversionsl' and "layers too thin" are common. Boundaries can be
mapped below hidden layers with GRM. Also, by using both P and
S-waves, additional boundaries can be mapped that would not have
'been seen using one technique in isolation.
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Schlumberger Soundings ,And Sand-Column Resistmty Testing For Determining Stream-Aquifer Connection Great Sand Dunes Natl. Monument., Colorado
Authors Eric J. Harmon and Marilyn F. HajicekThe Great Sand Dunes National Monument, located in south-central Colorado, is comprised of
approximately 4002 Km of Holocene eolian sand dunes together with several surface streams and their
associated riparian ecosystems. The dune field and its two major physiographic boundaries, i.e. Sand
Creek on the north and Medano Creek on the south, together form a complex and unique system for the
study of eolian transport and recycling, including an unusual streamflow phenomenon known as bedform
dependent pulsating flow. Federal officials perceived that a very large ground-water pumping
project proposed for an area less than ten miles north of Sand Creek threatened its flow, and thus its
associated physical transport phenomena andriparian ecosystem, as well as Federal reserved water rights
decreed to the National Monument. The magnitude of the threat depends upon the degree of hydraulic
connection between the surface flow in Sand Creek and the underlying aquifer system.
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Hydraulic Aquifer Characteristics Determined From Resistivity Sounding Parameters Using Empirical Formulae And Geostatistical Techniques
Authors V.D.A. Coetsee, R. Meyer, C.D. Elphinstone, H. Bezuidenhout and A. WatsonGeohydrological data obtained through pump tests, are typically scarce and expensive.
Geophysical observations on the other hand are less expensive and can be obtained more
readily. Where geophysical observations can be shown to correlate with geohydrological
properties the potential exists for augmenting a sparse geohydrological data set with
predictions based on geophysical observations.
This paper describes the results obtained with the direct current resistivity method, using
the Vertical Electrical Sounding (VES) technique in defining certain aquifer characteristics,
i.e. transmissivity and porosity. In the past many attempts have been made to establish
empirical hydrogeophysical relationships, without understanding the physical principles of
the problem completely.
The complicated relationship that exists between formation geometrical factors, and the
governing ground water and current flow equations, resulted in the use of geostatistics to
interpolate hydraulic values to unknown points in the aquifer, using direct current
resistivity parameters.
In this study results from the use of empirical methods, geostatistical methods like kriging
and co-kriging are compared. Advantages and disadvantages in applying these
geostatistical techniques are discussed.
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Application Of Magnetic And Electromagnetic Methods To Metal Detection
Authors Robert H. Gilkeson, Stephen R. Gorin, Roy F. Weston and Douglas E. LaymonMagnetic and electromagnetic methods are routinely used to search for buried metal targets on
environmental sites. The methods are used to explore directly for buried tanks, buried pipe lines,
and individual or caches of buried steel drums. In addition trenches that contain hazardous waste
may also contain enough metallic debris to be detected with these methods.
Surveys are often performed with both methods to collect four different but complimentary
measurements. The two magnetic measurements are total intensity of the magnetic field and
vertical gradient of the magnetic field. The two electromagnetic measurements are quadrature
component (apparent conductivity) and in-phase component (metal detection). Electromagnetic
measurements are sensitive to all types of metal whereas magnetic measurements only detect
ferromagnetic metals. The Geonics EM-31 D terrain conductivity meter is a popular instrument for
environmental surveys. The instrument will simultaneously measure apparent conductivity and
presence of buried metal. The depth of investigation with electromagnetic methods is in part
controlled by instrument design. Therefore, this paper presents findings on detection of buried
metal that are specific to the Geonics EM-31 D instrument.
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Ground Penetrating Radar Survey Design
Authors A.P. Annan and S.W. CoswayEffective ground penetrating radar (GPR) surveys entail substantial planning if the surveys
are to meet pre-defined objectives. For many years, GPR has often been used with
unrealistic expectations in the mind of the end user of the data. The tools for survey design
are available and should be used routinely by geophysicists contemplating GPR surveys.
This paper presents basic guidelines for selecting operating frequency, station spacing, line
spacing, and antenna orientation. In addition, the fundamental methods for assessing
suitability of a GPR survey for a specific application are outlines.
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