DART geophysics Flashres64 Survey

Electrical Imaging Resistivity data collected from geophysical surveys at the DART geophysical survey areas (Cherry Copse and Quarry Field at Cirencester - Diddington Clay and Diddington Pasture at Diddington) over the DART fieldwork season from June 2011 to September 2012. The survey was conducted using a ZZ FlashRes64 Electrical Imaging System (ERI). 64 probes, separated by a spacing of 0.2 metres, are laid out in a straight line in a series of traverses. Each survey line is therefore 12.6m in length. 6 surveys are conducted over each geophysical location, with a spacing of 2m between surveys. Measurement intervals were designated by marked survey lines with measurements taken when activated by a computer initialisation, and recorded whilst stationary within the ground. At each measurement station the computer automatically switched the probes inducing current into the ground, enabling a vast amount of data to be accumulated through a section of the earth, at various depths. The survey is part of a monthly collection programme of data collection over 2011-2012.

Data and Resources

Additional Info

Field Value
Author Robert Fry
Maintainer Anthony Beck
instrument ZZ Geo FlahsRes64 Electrical Resistivity Imaging Instrument
instrument.calibrationDetails Bought in 2011 from ZZ-Geo, Australia (http://www.zzgeo.com/
instrument.geophysics.areaSurveyed 6* 12.6m traverses spaced 2m apart
instrument.geophysics.dataGridSize Each survey extends 12.6m in length. 6 surveys spaced 2m apart provide a rough area of 12.6m X 10m grid.
instrument.geophysics.directionOfFirstTravers For direction, see probe 1 as the start and probe 64 as the end of each survey line: HHCC = NW, HHQF = NE, DDPF = NW, DDCF = SE
instrument.geophysics.earthResistanceSurvey.electrodeConfiguration Processed data combined into Wenner alpha, Wenner beta Wenner-Schlumberger, and Double-Dipole configurations.
instrument.geophysics.earthResistanceSurvey.electrodeSpacing 0.2m
instrument.geophysics.methodOfCoverage 2D in-line survey
instrument.geophysics.sampleInterval 0.2m
instrument.geophysics.surveyType Electrical Resistivity Imaging (ERI, ERT)
instrument.geophysics.traverseSeparation 2m
instrument.headerMetadata Survey details (location, manager, date etc)
instrument.measurementDomainAndUnits Resistivity (Ohm.m)
resource.abstract Electrical Imaging Resistivity data collected from geophysical surveys at the DART geophysical survey areas (Cherry Copse and Quarry Field at Cirencester - Diddington Clay and Diddington Pasture at Diddington) over the DART fieldwork season from June 2011 to September 2012. The survey was conducted using a ZZ FlashRes64 Electrical Imaging System (ERI). 64 probes, separated by a spacing of 0.2 metres, are laid out in a straight line in a series of traverses. Each survey line is therefore 12.6m in length. 6 surveys are conducted over each geophysical location, with a spacing of 2m between surveys. Measurement intervals were designated by marked survey lines with measurements taken when activated by a computer initialisation, and recorded whilst stationary within the ground. At each measurement station the computer automatically switched the probes inducing current into the ground, enabling a vast amount of data to be accumulated through a section of the earth, at various depths. The survey is part of a monthly collection programme of data collection over 2011-2012.
resource.accessConstraints None
resource.bibliographicCitation @data{dart_geophysics_flashres64, doi = {not allocated}, url = {http://dartportal.leeds.ac.uk/dataset/dart_geophysics_flashres64}, author = {Robert Fry}, publisher = {The DART project, School of Computing, University of Leeds}, title = {DART geophysics Flashres64 Survey}, year = {2013}, note = {DART is a Science and Heritage project funded by AHRC and EPSRC. Further DART data and details can be found at http://dartportal.leeds.ac.uk}}
resource.completeness Complete
resource.consistency Consistent data structure, attribution and relationships.
resource.creation.endDateTime 2012
resource.creation.startDateTime 2011
resource.creation.status Complete
resource.creator.email r.j.fry@student.bradford.ac.uk
resource.creator.name Robert Fry
resource.creator.orcID http://orcid.org/0000-0002-9711-1131
resource.custodian.email a.r.beck@leeds.ac.uk
resource.custodian.name Anthony Beck
resource.custodian.orcID http://orcid.org/0000-0002-2991-811X
resource.description Electrical Imaging Resistivity data collected from geophysical surveys at the DART geophysical survey areas (Cherry Copse and Quarry Field at Cirencester - Diddington Clay and Diddington Pasture at Diddington) over the DART fieldwork season from June 2011 to September 2012. The survey was conducted using a ZZ FlashRes64 Electrical Imaging System (ERI). 64 probes, separated by a spacing of 0.2 metres, are laid out in a straight line in a series of traverses. Each survey line is therefore 12.6m in length. 6 surveys are conducted over each geophysical location, with a spacing of 2m between surveys. Measurement intervals were designated by marked survey lines with measurements taken when activated by a computer initialisation, and recorded whilst stationary within the ground. At each measurement station the computer automatically switched the probes inducing current into the ground, enabling a vast amount of data to be accumulated through a section of the earth, at various depths. The survey is part of a monthly collection programme of data collection over 2011-2012. The survey conducted with the instrument allows for a vertical profile of electrical resistivity to be imaged so that the impact of dynamic environmental processes on the resistivity variation within the soil profile can be captured. Electrical Resistivity Imaging (ERI): ZZ FlashRes64: These instruments measure the electrical resistivity of the earth, using a multi-channel computer controlled switching system (two current and sixty-two potential probes at each measurement). Depending on the arrangement of these electrodes an exact measurement of a specific volume of earth may be acquired. This apparent resistivity value may then be used to calculate the real earth resistivity, using inversion techniques. When calculated, resistivity is in ohm-metres. The resistivity method as used for this area survey employs multiple probe separations ranging from 0.2m to 12.6m, which samples approximate hemispheres between the probes. Hence, a greater depth of investigation is theoretically possible with a wider probe spacing. The nature of the overburden and underlying geology will cause variations in this depth. All of the data are stored on a laptop computer for subsequent post-processing and analysis. The instrument is connected to a computer via a USB-Serial cable on site. The surveys consist of individual survey lines (2D lines) at a length of 12.6m. Data files are constructed to show which current-pair probes are used at each station, with a value of the resistivity given for each potential probe in relation to it. Up to 15,151 RAW measurements are calculated per 2D survey. The raw data file shows the current and voltage from the electrodes during the survey. The header lines contain spaces for the location, date, manager, voltage, current injection peroid, and survey mode. Due to a bug in the software, the survey location and manager do not get filled in, as these prevent the survey collecting data. A survey mode of 256 indicates how many current pairs were used in the survey. Below the header lines, the lines Spare P1, P2, P3, P4 are not filled in, and indicate spare these are not used for the survey and are a functon of future-proofing for further hardware. The Electrode positions table are in colums of Electrode number, x-position (electrodes spaced at intervals of 0.2m), y-position (usually 0 each line), and the z-position (electrodes on ground surface and therefore 0). The table which follows has the following columns: current pair, C1 electrode, C2 electrode, electrical current (amps), and probe electrical potential information. It is worth noting that the odd electrodes electrodes (1,3,5,7,9.. 63) take up the first 32 columns, and even numbered electrodes (2,4,6,8,10.. 64) take up the following 32 columns. This is due to the way the instrument collects data for cross-borehole surveys. The raw data collected can be entered into a software program which collates the data into various standardised arrays ready for inversion into either Geotomos Res2DInv, or BERT for the inversion process. This code, developed by Finnegan Pope-Carter, Thomas Sparrow and Robert Fry at the University of Bradford is available here: https://bitbucket.org/popefinn/trad-array-extract Filenames are arranged first by project (DART), then by instrument (FlashRes64) then by location (HHCC, HHQF, DDCF, DDPF), then date (YYYYMMDD), then by the survey line (1 to 6).
resource.distribution.technique Download only
resource.edition 1
resource.fileFormat .txt, .zip
resource.funder Science and Heritage Programme, Arts and Humanities Research Council, Engineering and Physical Sciences Research Council
resource.instructionalMethod None - this is a collection
resource.keywords Geophysics, Archaeology, Monitoring, Remote Sensing, Resistivity, ERI, ERT, Electrical Imaging
resource.language eng
resource.license odc-by
resource.license.typeURL http://opendatacommons.org/licenses/by/
resource.lineage None: this is raw data
resource.localURI http://dartportal.leeds.ac.uk/storage/f/dart_geophysics_flashres64
resource.metadata.creator.email r.j.fry@student.bradford.ac.uk
resource.metadata.creator.name Robert Fry
resource.metadata.creator.orcID http://orcid.org/0000-0002-9711-1131
resource.metadata.language eng
resource.processingStage Complete
resource.processingSteps Raw data is entered into a code-based program designed at the University of Bradford where standardised resistivity arrays (Wenner alpha, Wenner beta, Wenner-Schlumberger, Double-dipole) are created from the dataset. A combined array, employing all the standardiesd arrays is also created. The arrays extracted are in the Geotomo Res2DInv format for Inversion.
resource.publisher School of Computing, University of Leeds
resource.purpose multi-temporal heritage detection
resource.relatedResources DartProjectOverview
resource.repositoryName http://dartportal.leeds.ac.uk/
resource.reuseConstraints No conditions apply for reuse (remix it, publish it, share it, commercialise it, sell it etc.) except attribution (see resource.bibliographicCitation)
resource.reusePotential archaeology, environment, heritage, soil science, farming, ecology, geography, earth science
resource.samplingStrategy Electrical Resistivity Imagaing survey across a known archaeologcal feature (a ditch) was undertaken with survey lines 12.6m in length containing 64 electrodes spaced 0.2m apart. 6 ERI survey lines are collected over the survey location, spaced 2m apart. Survey data is collected once a month over the 15 month survey period.
resource.topic geoscientificInformation, environment, heritage, farming, climatology/Meteorology/Atmosphere, imageryBaseMapsEarthCover, society, structure
resource.type Dataset collection
resource.type.specific Geophysics
resource.updateFrequency not planned
spatial { "type": "Polygon", "coordinates": [ [ [-1.907587, 52.280552],[-0.246205, 52.280552], [-0.246205, 51.703178], [-1.907587, 51.703178], [-1.907587, 52.280552] ] ] }
spatial-text United Kingdom
spatial.boundingBox.OSGB36.east 519741
spatial.boundingBox.OSGB36.north 266160
spatial.boundingBox.OSGB36.referenceSystem OSGB36
spatial.boundingBox.OSGB36.south 200497
spatial.boundingBox.OSGB36.west 406483
spatial.boundingBox.WGS84.eastLongitude -0.246205
spatial.boundingBox.WGS84.northLatitude 52.280552
spatial.boundingBox.WGS84.referenceSystem WGS84
spatial.boundingBox.WGS84.southLatitude 51.703178
spatial.boundingBox.WGS84.westLongitude -1.907587
spatial.defaultReferenceSystem OSGB36
spatial.driftGeology DDCF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=TILMP, DDPF: http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=T1T2, HHCC: Clay: no superficial drift geology, HHQF: no superficial drift geology
spatial.landuse Permanent pasture: DDPF, Arable: DDCF, HHCF, HHQF
spatial.ordnanceSurveyPlaceName Harnhill (http://data.ordnancesurvey.co.uk/id/50kGazetteer/109734) and Diddington (http://data.ordnancesurvey.co.uk/id/50kGazetteer/72767)
spatial.polygon.OSGB36 { "type": "Polygon", "coordinates": [ [ [406483, 266160],[519741, 266160], [519741, 200497], [406483, 200497], [406483, 266160] ] ] }
spatial.polygon.WGS84 { "type": "Polygon", "coordinates": [ [ [-1.907587, 52.280552],[-0.246205, 52.280552], [-0.246205, 51.703178], [-1.907587, 51.703178], [-1.907587, 52.280552] ] ] }
spatial.solidGeology DDCF and DDPF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=OXC, HHCC: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=CB, HHQF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=SI
temporal.rangeDescribedByDataDateTime.end 2011
temporal.rangeDescribedByDataDateTime.start 2012
temporal.resource.availableDate 2013-07-15
title.alternative dart_geophysics_flashres64
title.pattern Where appropriate each resource has been named with the following pattern: DART_<3 character sensor/collection name>_<spatial location>_<StartDateTime YYYYMMDD with optional HHMM>_<endDateTime YYYYMMDD with optional HHMM>_<stage PRO or RAW to refer to processed or raw data>_<other stuff>.<suffix>. Hence, the file DART_T3P_DDCF_20110823_20130106_PRO.csv refers to DART data collected using the T3P Imko soil moisture probes at Diddington Clay Field between 23rd August 2011 and 6th January 2013 which has been processed and is available in a comma separated text format.