Loading ...
Sorry, an error occurred while loading the content.

GEOSTATS: interpolating/modelling groundwatercontamination

Expand Messages
  • Romijn, R.
    I have a question on interpolating/modelling groundwatercontamination. I m using geostatistic applications for interpolating ground- and
    Message 1 of 2 , Jun 3, 1999
    • 0 Attachment
      interpolating/modelling groundwatercontamination

      I have a question on interpolating/modelling groundwatercontamination. I'm using geostatistic applications for interpolating ground- and groundwatercontamination. This is done mainly by use of 3D-moving-window-kriging and information on contamination at borehole-level (at different depths). In this case, the 3D in 3D-moving-window-kriging means that not only data at the same horizontal level are used, but also data at other levels (horizontal and vertical semivariograms).

      Interpolation for the groundcontamination works alright. However, the results obtained by interpolating groundwatercontamination are kind of poor. Many times obvious "areas" with higher contamination levels than the surrounding area are not interpolated as such. I do not really know what the problem is. Maybe I need to use an anisotropic interpolation technique, in order to model the groundwater movement (small scale)? I do not have much experience using anisotropy.

      Does anyone have similar experiences with interpolating/modelling groundwatercontamination or does anyone have some good ideas about interpolating/modelling groundwatercontamination?

    • Pierre Goovaerts
      Hi Romijn, 3D interpolation must be done with great care in order to avoid severe artifact which may result from a poor choice of data (search strategy)
      Message 2 of 2 , Jun 3, 1999
      • 0 Attachment
        Hi Romijn,

        3D interpolation must be done with great care
        in order to avoid severe artifact which may result from a poor
        choice of data (search strategy) retained in kriging.
        Typically, you will need to use a 3-D anisotropic semivariogram
        model and an anisotropic search window (ellipsoid).
        The choice of the search window will depend on the distance
        between boreholes and the sampling density along the vertical
        direction. You may want to do a sensitivity analysis
        to investigate the impact of your search strategy on the results.

        What do you mean by "an anisotropic interpolation technique, in
        > order to model the groundwater movement (small scale)? "

        Pierre
        <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>

        ________ ________
        | \ / | Pierre Goovaerts
        |_ \ / _| Assistant professor
        __|________\/________|__ Dept of Civil & Environmental Engineering
        | | The University of Michigan
        | M I C H I G A N | EWRE Building, Room 117
        |________________________| Ann Arbor, Michigan, 48109-2125, U.S.A
        _| |_\ /_| |_
        | |\ /| | E-mail: goovaert@...
        |________| \/ |________| Phone: (734) 936-0141
        Fax: (734) 763-2275
        http://www-personal.engin.umich.edu/~goovaert/

        <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>


        On Thu, 3 Jun 1999, Romijn, R. wrote:

        > I have a question on interpolating/modelling groundwatercontamination. I'm
        > using geostatistic applications for interpolating ground- and
        > groundwatercontamination. This is done mainly by use of
        > 3D-moving-window-kriging and information on contamination at borehole-level
        > (at different depths). In this case, the 3D in 3D-moving-window-kriging
        > means that not only data at the same horizontal level are used, but also
        > data at other levels (horizontal and vertical semivariograms).
        >
        > Interpolation for the groundcontamination works alright. However, the
        > results obtained by interpolating groundwatercontamination are kind of poor.
        > Many times obvious "areas" with higher contamination levels than the
        > surrounding area are not interpolated as such. I do not really know what the
        > problem is. Maybe I need to use an anisotropic interpolation technique, in
        > order to model the groundwater movement (small scale)? I do not have much
        > experience using anisotropy.
        >
        > Does anyone have similar experiences with interpolating/modelling
        > groundwatercontamination or does anyone have some good ideas about
        > interpolating/modelling groundwatercontamination?
        >

        --
        *To post a message to the list, send it to ai-geostats@....
        *As a general service to list users, please remember to post a summary
        of any useful responses to your questions.
        *To unsubscribe, send email to majordomo@... with no subject and
        "unsubscribe ai-geostats" in the message body.
        DO NOT SEND Subscribe/Unsubscribe requests to the list!
      Your message has been successfully submitted and would be delivered to recipients shortly.