A downhole seismometer is in one of the holes and the shear wave source in the other. Maswremi surface waves data processing and interpretation, 2. Divine microseismic and seismic tomographic imaging software divine is a modular, 2d and 3d microseismic and active seismic imaging and modelling package for microseismic data processing and monitoring and crosshole, vsp, surface reflection, single well and critical refraction survey processing. Crossholedownhole seismic investigations provide information on dynamic soil and. Seismic surveys are also a costeffective way to extend information derived from borehole logs over a much larger area, minimizing the need for costly multiple borings. Earthquake engineering software the nisee software library cdrom, a collection of research software developed from the 1960s through the early 1990s, is sold out. Acoustic waveequation traveltime and waveform inversion of. Fractured or weak concrete zones lower the velocity of the seismic waves and can, therefore, be detected. Crosshole sonic logging csl and 3d tomography what is crosshole sonic logging. The essential engineering analysis tool from beams to tall buildings, from simple structures to the most complex, gsa analysis is the program to help solve engineering problems. Crosshole seismic surveys are used to obtain in situ properties of soil and rock strata.
Often used as part of a comprehensive geotechnical investigation, the crosshole. General crosshole procedures environmental geophysics. The list is split into broad categories, depending on the intended use of the software and its. The nisee software library cdrom, a collection of research software developed from the 1960s through the early 1990s, is sold out. Pdf crosshole seismic testing is a valuable technique for determining. We design seismic borehole sources and receivers and develop specifically tailored software. Seismic surveys provide information about stratigraphy, hydrogeology, and bedrock topography. In addition, a 2d imaging analysis based on first arrival time is also conducted. The csds2 model is the base model for crosshole or downhole seismic testing.
These tests are used to obtain shear and compression wave velocities in a borehole for a variety of geotechnical applications. Crosshole sonic logging csl uses compressional seismic waves as the energy source. An accelerometer is also included to trigger data collection for downhole seismic testing. Pdf the potential of seismic crosshole tomography for. The utilization and interpretation of these basic tests is well. Standard test methods for crosshole seismic testing. Mar 24, 2015 crosshole astm d4428 v s measurements are typically performed between boreholes, one with a mechanicallyactivated source and at least two others with receivers takahashi et al. Seismic data can be sorted and edited and traveltimes can be determined. Crosshole sonic logging csl and 3d tomography what is crosshole sonic logging csl csl integrity testing is performed by transmitting and receiving an ultrasonic signal between two parallel access tubes cast into a deep foundation element. This is a list of free and opensource software for geophysical. The crosshole seismic cs system and method determine shear and compressional wave velocity versus depth profiles. The field crosshole data were collected by exxon chen et al. Fewer boreholes are needed to achieve a continuous picture of the subsurface thereby reducing overall costs and the risk of missing target features. Perform day to day analysis and solve complex engineering problems within the same.
A number in parentheses indicates the year of last reapproval. Correlation between cs and spectral analysis of surface waves sasw. The ct method uses data from multiple csl logs at different sourcereceiver height offsets. Seismic waves passing through concrete are influenced by the density and elastic modulus of the. Seismic data for crosshole testing need considerably more waveform interpretation because refraction events from highvelocity layers either above or below a lowvelocity layer must be.
This procedure is covered by an astm guideline but has several variants. Schuster, and sia hassanzadeh abstract a hybrid waveequation traveltime and waveform inversion method is presented that reconstructs the interwell velocity distribution from crosshole seismic data. The crosshole seismic cs system and method determine shear and. Pdf timefrequency coherency analysis of threecomponent. The software is used to process seismic crosshole testing data obtained after astm4428 and to output results. Gsa gsa analysis is the program to help solve engineering problems. Crosshole or crosswell seismic measures the velocity of seismic waves between boreholes.
Holetohole logging environmental geophysics us epa. Seismic interpretation software, refraction analysis, cross. It covers the complete range of wave data seismic, gpr, ultrasound and with the different geometry assemblings surface reflection and refraction, borehole crosshole and tomography and combination of borehole and surface. This approach is a little more definitive for acquiring information on discrete layers. The project engineer has at his disposal several methods for determining these properties in situ.
Acoustic waveequation traveltime and waveform inversion. Vp and vs are determined up to the depth of 55 m with an interval of 1. Csl integrity testing allows an evaluation of concrete integrity and homogeneity within the shaft. Developer of rayfract seismic refraction, crosshole, and vsp tomography software. Radar gpr and seismic data processing and interpretation software, finite. Crosshole velocity data are valuable for assessing manmade materials, soil deposits, or rock formations. Reflexw gpr and seismic processing software sandmeier. If snells law of refraction is not considered in the analysis of crosshole seismic testing data, the report shall so state, and the pwave and swave velocities obtained may be unreliable for certain depth intervals near changes in stratigraphy 2. Pdf application of crosshole seismic tomography in. Our software reflexw is one of the worlds most popular geophysical near. A procedure is presented whereby field programs can be more rationally planned. The primary application of borehole seismic tomography is in engineering studies for the identification of features such as fault zones and voids. Seismic waves passing through concrete are influenced by the density and elastic modulus of the concrete.
This software package includes crosshole survey design, model building and modeling, data preprocessing, cdp transformation, tomography, waveequation migration, and postprocessing. When combined with an swave survey, the data can additionally be used to provide information on material stiffness properties see crosshole seismic surveys. Refraction waves forward modeling and inversion in arbitrary layered. View our crossholedownhole seismic testing equipment to learn more. In this paper we have discussed several practical issues in the application of crosshole seismic waveform tomography when dealing with real data. Seismic tomography, crosshole, downhole geotomographie gmbh. Seismic interpretation software, refraction analysis, cross hole data. Crossholedownhole seismic csds investigations provide information on dynamic soil and rock properties. Crosshole seismic tomographic data and borehole logs were acquired in the median separating the east and west bound lanes of u. Crosshole sonic logging csl is a method to verify the structural integrity of drilled shafts and other concrete piles the csl method is considered to be more accurate than sonic echo testing in the determination of structural soundness of concrete within the drilled shaft inside of the rebar cage. Crosshole sonic logging integrity testing is standardized by astm d6760 standard test method for integrity.
Borehole seismic methods largely fall into two categories, namely, crosshole seismics and seismic tomography. Pdf seismic crosshole tomography has been commonly used in oil and gas exploration and the mining. Rayfractr geophysical software for geotechnical engineering and exploration generates subsurface velocity models from seismic first break data. As a part of the feasibility study crosshole seismic and multi channel analysis of surface waves. Crosshole tomography ct testing and analysis is normally used in conjunction with crosshole sonic logging csl testing to provide additional information as to the size, shape. Crosshole sonic logging csl is a method to verify the structural integrity of drilled shafts and other concrete piles the csl method is considered to be more accurate than sonic echo. It is important that the hole is cased and wellgrouted to ensure good seismic coupling between the geophone and the surrounding soil and rock. Many foundation dynamics and soilstructure interaction problems require insitu values of shear wave velocities and elastic moduli, or both, for foundation materials. Joint inversion of crosshole gpr and seismic traveltime data. It reads seismic data acquired during a cptus measurement or downhole test. Cluin technologies characterization and monitoring.
The cross hole seismic test is conducted on field as per the astm d 4428is 372 part 2. Crosshole seismic surveys measure the time for horizontally traveling compressional p and shear s waves to travel from a source hole to a receiver hole. Multihole seismic modeling in 3d space and crosshole. Widely available spreadsheet software is typically equipped with sophisticated features, such as programmability and handling of complexvalued data even fourier analysis, rendering these. Acoustic waveequation traveltime and waveform inversion of crosshole seismic data changxi zhou, wenying cai, yi gerard t. Many foundation dynamics and soilstructure interaction problems require insitu values of shear wave velocities and elastic moduli, or both.
This structural analysis software program is used across the globe on all manner of projects. Acquisition and processing software is easy to use, yielding fast and accurate results. A case history is presented from the chranokite province of mahabalipuram, tamilnadu. Crosshole seismic overview a threeaxis geophone is lowered into a speciallyprepared, cased borehole and excited with a hammer source in a similar borehole nearby. Seismics machine learning and analytics capabilities continuously improve the entire enablement process for large enterprises, increasing the roi of sales content and tying it directly to. Zondst2d is designed for twodimensional interpretation of seismic tomography data on refracted and reflected waves land, crossborehole and water variants. Crosshole seismic tomography and borehole logging for. Seismic data processing software geotomographie gmbh.
Spas is a simple seismic signal processing seismic analysis software. Timefrequency coherency analysis of threecomponent crosshole seismic data for arrival detection article pdf available in geophysics 636. The pwave and swave velocities are directly related to the important geotechnical elastic constants of poissons ratio, shear modulus, bulk modulus, and youngs modulus. Standard test methods for downhole seismic testing1 this standard is issued under the. Crosshole testing allows for the generation and measurement of both vertically sv and horizontally sh polarized shear waves roblee et al. As a part of the feasibility study crosshole seismic and multi channel analysis of surface waves masw surveys were conducted near the heavy construction site. Gpr and seismic data processing software sandmeier. Pdf crosshole seismic testingprocedures and pitfalls. A seismic source is used to generate a seismic wave train at the. Travel times are used to determine p and s wave velocities, which can be used to compute poissons ratio, as well as the other elastic moduli. The software is used to process seismic crosshole testing data obtained after. The crosshole sonic logging method is normally applied as a quality assurance qa technique for newly placed drilled shafts and auger cast piles, but can also be applied. Crosshole astm d4428 v s measurements are typically performed between boreholes, one with a mechanicallyactivated source and at least two others with receivers. This system includes two triaxial geophones and all necessary accessories for crosshole seismic testing when used with a downhole source.
Supports pwave, swave and crosshole survey interpretation. Our software reflexw is one of the worlds most popular geophysical near surface processing and interpretation packages. Crosshole tomography ct testing and analysis is normally used in conjunction with crosshole sonic logging csl testing to provide additional information as to the size, shape, and location of a defect which has been located with standard csl testing. Finally, the results of 2d analysis in 3d modeling space are comparatively analyzed with the physical model test. These tests are used to obtain shear and compression wave velocities in a. Conetec has completed downhole seismic testing dst and crosshole seismic testing cst for over 30 years. Reflexw software, according to selected module, covers complete range of wave data seismic, gpr,ultrasound and their processing throgh different geometry assemblings such as. Singleshot cmp processing sorting, display, processing, nmoanalysis, stacking. Crosshole downhole seismic csds investigations provide information on dynamic soil and rock properties. First, the crosshole seismic tomography method eliminates depthrelated restrictions.
The rayfract software can also be used with crosshole and vsp survey data to generate twodimensional, tomographic images of subsurface seismic velocity variations. Application of crosshole seismic technique and mafiadoc. From these measurements, parameters, such as poissons ratios and moduli, can be easily determined. If snells law of refraction is not considered in the analysis of crosshole. Conetec compression and shear wave velocity testing. Crosshole survey the difference between this survey and the downhole one is that in the crosshole approach there are two boreholes.
Pditomo tomographic software is available for superior tomographic results providing intuitive 3d identification of questionable areas, as well as allowing for a quick and easy quantitative. Seismic methods can provide detailed information about rock properties and geological structure between boreholes. The software provides reflection analysis, refraction analysis, downhole data inversion, cross hole data interpretation. It covers the complete range of wave data seismic, gpr, ultrasound. Pditomo tomographic software is available for superior tomographic results providing intuitive 3d identification of questionable areas, as well as allowing for a quick and easy quantitative, comprehensive, engineering analysis. As real crosshole seismic data in most cases do not contain lowfrequency components software. The investigation was conducted in accordance with the requirements in astm d4428 standard test methods for crosshole seismic testing and astm d7400 standard test methods for. Then, crosshole seismic numerical simulations and response characteristics of two boulder models are studied in 3d space. The primary purpose of obtaining crosshole data is to obtain the most detailed in situ seismic wave velocity profile for sitespecific investigations and material characterization. Tomoxpro is the only commercial crosshole software package in the seismic industry. This is a list of free and opensource software for geophysical data processing and interpretation. Often used as part of a comprehensive geotechnical investigation, the crosshole seismic survey yields valuable information as to the strength and cohesiveness of the underlying sediment and bedrock, information that is critical to any engineering endeavor. Crosshole seismic test procedures are outlined in astm test. It is similar in several respects to the crosshole seismic test method test methods d 4428d 4428m.
Crosshole seismic tomography which involves measuring travel times. Crosshole and downhole seismic cdds crosshole seismic and downhole seismic system is used for providing information on dynamic soil and rock properties for earthquake. Seismic interpretation software, refraction analysis. Perform day to day analysis and solve complex engineering problems within the same environment 2. Fewer boreholes are needed to achieve a continuous picture of the. Crosshole sonic logging csl is the most accurate and reliable technique for assessing the integrity of deep foundation elements constructed onsite from concrete or grout. Joint inversion of crosshole groundpenetrating radar and seismic data can improve model resolution and fidelity of the resultant individual models. Source code on the cdrom and most of the manuals are now available through the earthquake engineering online archive. Crosshole and downhole seismic cdds crosshole seismic and downhole seismic system is used for providing information on dynamic soil and rock properties for earthquake design analyses for structures, liquefaction potential studies, site development, and dynamic machine foundation design. Standard test methods for downhole seismic testing1.
Crosshole sonic logging csl is the most accurate and reliable technique for assessing the integrity of deep foundation elements constructed onsite from concrete or. Application of crosshole tomography for assessment of. Invariant are requirements to measure both p and s waves and to use a reversible source to aid in. It is possible to implement the deviation of the boreholes. In addition, a 2d imaging analysis based on first arrival time.