GADDS Help

Geophysical Archive Data Delivery System Help

  1. Step 1 - Access Window
  2. Step 2 - Data Type and Theme Window
  3. Step 3 - Choosing datasets for download
  4. Field Name Definitions
  5. Submit Request
  6. Help Link

Accessing Geophysical Survey Datasets

Access to GADDS is via the URL, www.geoscience.gov.au/GADDS/.

What do I do if I need help with GADDS?

If you are having problems contact the Airborne Surveys Database Administrator at Geoscience Australia. Details are as follows:

Murray Richardson.

Telephone - 02 6249 9229.

or via e-mail - murray.richardson@ga.gov.au


    Step 1 - Access Window

    1.1 Data Search

    The access window allows the user to define the area of interest. The page opens with the Australian coastline theme active (this layer cannot be turned off). The user can add themes by selecting them from the list of check boxes on the right of the page.

    Basic navigation is done using the four buttons to the right of the map of Australia - zoom in, zoom out, pan and query (Figure 1).

    There are three ways to search for geophysical datasets. Either:

    Use the Lat/Long Rectangle or the Map Sheet Index window (right) side of the screen.

    Or

    Use the Map window (left) side of the screen.

    Geophysical Data Delivery System Lat/Long Rectangle and Map window.
    Figure 1. Geophysical Data Delivery System Lat/Long Rectangle and Map window.


    1.1.1 Lat/Long Window, Map Sheet Index (Right) Side of Screen

    Search co-ordinates can be entered in the fields supplied (nb: latitudes are negative in the southern hemisphere).

    Or select the name of a 1:250k Map Sheet from the drop down list to search for datasets covering that sheet.

    Once the area of interest has been defined press Proceed to Download to proceed to step 2.

    A new window will open.


    1.1.2 Map Window (Left) Side of Screen

    This window enables you to select datasets by dragging a box with the mouse over the area of interest on the map. You can use the navigation keys of this window to define a search area. Notes on the function of each navigation key will be displayed when the mouse is moved over the keys, they include:

    Once the area of interest has been defined press Proceed to Download to proceed to step 2.

    A new window will open.


    1.1.3 Additional Layers

    The check boxes under the Additional Layers heading allow for display of the following layers on the map of Australia

    Note:The population, roads and railways layers will only display when the map is displayed at less than 1:3 000 000 scale.

    All other layers display at all scales.


    Step 2 - Data Type and Theme Window

    The Data type and theme window displays the geodetic coordinates selected and allows for selection of the data type (grid or vector) and theme (magnetics, radiometrics, elevation, gravity) from the drop down lists (Figure 2).

    Data Type and Theme window.
    Figure 2. Data Type and Theme window.

    Select the datatype and theme then press Next to proceed to step 3.


    Step 3 - Choosing datasets for download

    3.1 Introduction

    This page displays all the datasets that meet the area of interest,data type and theme criteria (Figure 3).

    Window for choosing gridded datasets for download.
    Figure 3. Choosing gridded datasets for download.

    3.2 Raster Datasets

    Gridded datasets can be previewed by clicking on the Preview image link displayed under Additional Information at the bottom of each dataset (Figure 4).

    Gridded dataset preview window.
    Figure 4. Previewing gridded datasets.

    In the image window a link vis62223.gif is displayed. Clicking on this link with the right mouse button enables the image file (in gif format) to be saved to the customer's hard drive using the Save Target As... option.

    When downloading gridded datasets the Download this grid check box must be ticked. Datasets not required should not have a tick in the download check box.

    For each GRID dataset selected for download there are three choices for the resolution of the supplied dataset:


    3.3 Survey Extents

    The survey extents of each dataset can be displayed by clicking on Survey extent. A new window is opened with the selected survey area coloured in red (Figure 5). Click on Close window to exit this feature.

    Survey extent preview window.
    Figure 5. Previewing survey extents.

    For datasets at a national scale this feature is not available and National scale dataset. No survey details available will be displayed.


    3.4 Survey Metadata

    The survey metadata of each dataset can be displayed by clicking on Survey metadata. A new window is opened with all available metadata relating to that survey displayed (Figure 6). Click on X in the top right corner of this window to exit this feature.

    Survey metadata window.
    Figure 6. Viewing survey metadata.

    For datasets at a national scale this feature is not available and National scale dataset. No survey details available will be displayed.

    Select the radio button of your choice then press Next to proceed.


    3.5 Vector Datasets

    For each VECTOR dataset selected for download the dataset is supplied at the full dataset resolution.

    Click on the required check boxes to select the columns required from each vector dataset selected.

    This page displays all the datasets that meet the area of interest,data type and theme criteria (Figure 7).

    Window for choosing vector datasets to download.
    Figure 7. Choosing vector datasets for download.

    Datasets meeting the selection criteria are ordered in decreasing order of data file size.

    A percentage coverage estimate is given to indicate how much of the chosen dataset is in the region of interest.

    In Figure 7, the area of interest covers 0.1 degrees north-south and 1.5 degrees east-west. This slice is approximately 8% of the Dubbo magnetic point-located dataset.

    Datasets to be downloaded must have the Download the dataset vector checkbox displaying a tick.

    A note is displayed indicating that to select all fields of the dataset leave all field check boxes unchecked.

    If a subset of fields is required select the field of interest by clicking on the check box next to the required field.

    Definitions of all field names is given in the next section of this help file.


    4. Field Name Definitions

    Each vector dataset has standard fields that are listed for each dataset.

    For magnetic data these fields are listed and defined in the following table:

    Field names for magnetic datasets and their meaning
    Field NameDefinition
    altitudeMeanNominal survey altitude in metres above sea level
    bearingNominal line or tie bearing in degrees (0-359) measured east of true north
    dateCodeDate line or tie was acquired - yyyymmdd
    FIDFiducial at sample in data record
    fidFactorFiducial size in seconds (Factor to convert fiducial increment into seconds).
    flightFlight number for line or tie
    groundClearanceNominal survey altitude in metres above ground level
    latitudeLatitude in degrees
    LINEUnique line or tie number
    longitudeLongitude in degrees
    microlevelledAs for residual and also microlevelled
    residualLevelled total magnetic intensity - IGRF + 5000nT
    surveyUnique survey number identification
    timeOfDayTime of day at fiducial zero in seconds
    gridflagGridding flag 1=ignore, 0=use. Indicates whether the data point was used in grid generation

    For radiometric data these fields are listed and defined in the following table:

    Field names for radiometric datasets and their meaning
    Field NameDefinition
    altitudeAltitude in metres above ground level of survey aircraft
    altitudeMeanNominal survey altitude in metres above sea level
    bearingNominal line or tie bearing in degrees (0-359) measured east of true north
    dateCodeDate line or tie was acquired - yyyymmdd
    FIDFiducial at sample in data record
    fidFactorFiducial size in seconds (Factor to convert fiducial increment into seconds).
    flightFlight number for line or tie
    groundClearanceNominal survey altitude in metres above ground level
    latitudeLatitude in degrees
    LINEUnique line or tie number
    longitudeLongitude in degrees
    potassiumPotassium (counts/sec OR pctK)
    surveyUnique survey number identification
    thoriumThorium (counts/sec OR ppmTh)
    timeOfDayTime of day at fiducial zero in seconds
    totalcountTotal count (counts/sec OR nanoGrays/hour)
    uraniumUranium (counts/sec OR ppmU)

    For elevation data these fields are listed and defined in the following table:

    Field names for elevation datasets and their meaning
    Field NameDefinition
    altitudeMeanNominal survey altitude in metres above sea level
    bearingNominal line or tie bearing in degrees (0-359) measured east of true north
    dateCodeDate line or tie was acquired - yyyymmdd
    FIDFiducial at sample in data record
    fidFactorFiducial size in seconds (Factor to convert fiducial increment into seconds).
    flightFlight number for line or tie
    groundGround elevation in metres above sea level
    groundClearanceNominal survey altitude in metres above ground level
    latitudeLatitude in degrees
    LINEUnique line or tie number
    longitudeLongitude in degrees
    planeAircraft elevation in metres above ellipsoid
    surveyUnique survey number identification
    timeOfDayTime of day at fiducial zero in seconds

    For gravity data these fields are listed and defined in the following table:

    Field names for gravity datasets and their meaning
    Field NameDefinition
    projectSurvey number unique to each survey
    obsnoOracle database generated unique number
    stationnoStation number (includes project number)
    stationnameName of station
    stationtypeType of station eg. absolute, base, control, ground, helicopter etc.
    dlongLongitude
    dlatLatitude (negative) for the southern hemisphere
    posunitsPosition units (degrees, decimal degrees)
    acc_locEstimate of accuracy of the position, in metres
    datumPosition datum
    spheroidSpheroid used defined by the datum
    posmethodMethod used to position the station eg. digitised from map, GPS, etc.
    elevationElevation of ground at the station (metres above sea level)
    elevunitsUnits of the elevation
    acc_htEstimate of accuracy of the elevation, in metres
    elevdatumElevation datum
    elevmethodMethod used to define elevation eg. barometer, map, GPS, etc.
    elevtypeElevation description eg. land, marine, underground etc.
    obsdateDate observation was made
    countryidCountry observation was made in eg. Aus., PNG etc.
    gravObserved gravity value
    gravunitsUnits of the observed gravity
    acc_guEstimate of the accuracy of the observed gravity
    gravdatumObserved gravity datum
    calcdateDate gravity data were processed
    gravmethodGravity meter used eg. LaCoste-Romberg, Scintrex etc.
    gmeteridGravity meter serial number
    heightHeight of the gravity meter at the observation point
    heighterrorEstimate of the accuracy of the meter height
    heightmethodMethod used to obtain the height of the meter
    tcTerrain correction
    tcerrorTerrain correction accuracy estimate
    tcmethodMethod used to calculate the terrain corrrection eg. Hammer hand, Intrepid software etc.
    tcdensityDensity used in the terrain correction
    confidConfidentiality status of the station eg. open or embargoed
    reliabEstimate of the overall reliability of the reading (0 = unreliable, 7 = high reliability)
    statusStatus of the station (original or active)
    commentsComments made when observing the station
    parentShows either '-1' for the original version of the station that has been converted, or the obsno of the station from which it has been converted
    freeairFree Air Anomaly value
    bouguerBouguer Anomaly value at 2.67 tonne/cubic metre

    For airborne gravity data these fields are listed and defined in the following table:

    Field names for airborne gravity datasets and their meaning
    Field NameDefinition
    ProjProject Number
    FltFlight Number
    LineLine Number
    FidFiducial
    DateDate (yyyymmdd)
    BrgBearing (degrees East of North)
    LongFinal Longitude (degrees, GDA94)
    LatFinal Latitude (degrees, GDA94)
    LatRadFinal Latitude (radians, GDA94)
    mga53EFinal Easting (metres, GDA94,MGA53)
    mga53NFinal Northing (metres, GDA94, MGA53)
    GPSHtGPS Height above WGS84 Ellipsoid (metres)
    GPSTimeGPS time (seconds since start of day)
    CSatsCoarse Channel Saturations (1=saturation, 0=no saturation)
    FSatsFine Channel Saturations (1=saturation, 0=no saturation)
    RawFA???Raw Relative Free Air Anomaly (Unlevelled). WGS84, Helmert System. Units - micrometres/sec/sec** (gravity units)
    TieLvAdjTie Line Levelling Adjustment. Units - micrometres/sec/sec (gravity units)
    TieLvFA???Tie Line Levelled Relative Free Air Anomaly. WGS84, Helmert System. Units - micrometres/sec/sec (gravity units)
    NoiseAdjNoise Adjustment. Units - micrometres/sec/sec (gravity units)
    RelFA???Final Relative Free Air Anomaly. WGS84, Helmert System. Units - micrometres/sec/sec (gravity units)
    DCHelmertDC Adjustment to Absolute Gravity. WGS84, Helmert System. Units - micrometres/sec/sec (gravity units)
    AbsFA???HelEllipsAbsolute Free Air Anomaly. WGS84, Helmert System. Units - micrometres/sec/sec (gravity units)
    TerrainTerrain height (metres) (AHD71)
    NValueN-Value AusGeoid98 (metres)
    AHD71HtHeight above Geoid (metres) (AHD71)
    ObsFiltObserved Gravity - Filtered height term (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    ObsObserved Gravity - unfiltered height term (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    FA???GRS67AHDFiltFinal Absolute Free Air Anomaly (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    NormBCorrFiltNormalised Bouguer Correction, filtered to match gravity (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    BullardCorrFiltBullard (Earth Curvature) Correction, filtered to match gravity (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    B???Corr254Bouguer Correction, dens=2.54 (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    B???Corr267Bouguer Correction, dens=2.67 (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    NormTerr???CorrFiltNormalised Terrain Correction, filtered to match gravity (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    Terr???Corr254Terrain Correction, dens=2.54 (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    Terr???Corr267Terrain Correction, dens=2.67 (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    BA???sim254Final Absolute Simple Bouguer Anomaly (dens=2.54) (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    BA???sim267Final Absolute Simple Bouguer Anomaly (dens=2.67) (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    BA???com254Final Absolute Complete Bouguer Anomaly (dens=2.54) (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    BA???com267Final Absolute Complete Bouguer Anomaly (dens=2.67) (IGSN71, AHD71). Units - micrometres/sec/sec (gravity units)
    ???Filter Length 060, 080, 107 seconds
    **1 micrometre/sec/sec=0.1 mGal


    5. Submit Request

    The final step in the procedure is to acknowledge reading and agreeing with the terms of the data licence and privacy statements (Figure 8).

    Licence agreement

    Proposed use of data

    Registration authentication
    Figure 8. Licence agreement, data usage and client registration details.

    Read the licence conditions and tick the licence check box. Please also fill in the Development, Proposed Distribution of Data and Application check boxes where applicable. Please note all fields marked with an * must be filled in.

    Supply your name and contact details. The supplied e-mail address is the address for delivery of the requested data.

    A warning is supplied if the size if the requested dataset is greater than 200 megabytes. Files larger than 200Mb could take a long time to download on a slow internet connection.

    Note: Files to be downloaded are restricted to be less than 200 megabytes in size.

    For requests of datasets larger than 200 megabytes please contact Murray Richardson via e-mail murray.richardson@ga.gov.au or telephone him on (02) 6249 9229.

    Click Submit Form and the user will be informed that the data request has been submitted (Figure 9).

    Submitted request window
    Figure 9. Submitted request window.

    When the data has been extracted and zipped you will receive an e-mail with a link to the prepared data.

    The delivered e-mail will appear like the example in Figure 10.

    E-mail indicating successful completion of data request
    Figure 10. E-mail indicating successful completion of data request.

    Click on the link to the prepared data and select the Save this file to disk option (Figure 11). Click OK.

    Saving the zip file containing the requested datasets
    Figure 11. Saving the zip file containing the requested datasets.

    The Save As window opens (Figure 12). It is recommended that at this stage the zip file is given a name representative of the contained dataset. Click Save.

    Selecting the Open this file from its current location radio button will open the zip file as shown in Figure 14.

    Saving the zip file to your hard drive
    Figure 12. Saving the zip file to your hard drive.

    The download will commence and when completed the zip file can be opened (Figure 13).

    Download completed message
    Figure 13. Download completed message.

    Clicking on open will display the contents of the zip file (Figure 14).

    An example of the contents of the downloaded zip file
    Figure 14. An example of the contents of the downloaded zip file.

    For all datasets the zip file will contain copyright information in the file Copyright_Disclaimer.txt

    For gridded datafiles the filename convention is to have the airborne survey project number (Eg P569) and the dataset theme (Eg tmi for magnetics). The small g indicates a geodetic dataset is stored in the JetStream data directory

    Two files are supplied when choosing gridded datasets. The gridded datafile and the associated header with a .ers extension

    For vector datafiles the filename convention is to have the airborne survey project number (Eg P596) and the dataset theme (Eg MAG for magnetics)

    Three files are supplied when choosing vector datasets. The '.dat' file contains the vector dataset. The '.des' file contains dataset datum and projection information. The '.dfn' file contains dataset field name definitions and formats.


    6. Help Link

    If you are having difficulty searching for surveys, press the Detailed help link located on each page of GADDS to display these notes on how to use GADDS.