Territory Stories

Mary river coastal plain subsurface hydrology study 1992.



Mary river coastal plain subsurface hydrology study 1992.


Chin, D.; Martin, K.; Schwartz, T.; Jolly, P.


E-Publications; E-Books; PublicationNT; Report ; 20/1993




Made available via the Publications (Legal Deposit) Act 2004 (NT).





Publisher name

Power and Water Authority

Place of publication



Report ; 20/1993

File type


Copyright owner

Check within Publication or with content Publisher.

Parent handle


Citation address


Page content

Technical Report WRD93020 Viewed at 15:07:19 on 29/07/2010 Page 57 of 132. on the degree of field observation error, no attempt has been made to resolve this ambiguity by constraining the solutions with geological infonnation. However, the range of this ambiguity, consistent with an estimated 5% relative error in the field data and a 68% confidence limit for the solution parameters can be loosely estimated by the effective parameter (EFF. PAR) variable printed on each interpretation. Soundings correlate reasonably well with drilling and geophysical, natural gamma, logs. Unfortunately during the geophysical logging electric logs were not obtained for comparison with sounding data. TEM 6 (Ri~ 28360) defines a 0.5 ohmm conductor displayed in most soundings between 10 and 20m as a grey clay, mudstone, while the resistive unit identified at 18 20m is associated with a sandy clay and mottled lateritic zone. TEM 12 (R.N" 28363) again defines the 0.5 ohmm conductor as a grey clay/mudstone followed by a more resistive sand quartzose, clay lithology. This boundary is clearly defined on the ga=a log. TEM 22 (R.N" 28365) was not drilled deep enough to correlate with surface geophysics. The sounding did not differentiate between lithologies until 50m depth. Similarly, the gamma log does not differentiate between lithologies to total depth, 26m. Unfortunately TEM sounding 20, Rl~ 28366, could not be interpreted due to equipment and acquisition problems in the field. RN 28364 intersected, from surface, the outcropping Proterozoic lithologies as implied from dips determined in TEM soundings 1, 2, 3 and implied in AEM. The primary moment within TEM soundings were, at the time, aimed at defining shallow conductivity distnbution so a loop size was selected to suit these aims. To better define the deep conductive feature, displayed in soundings 10 through 13, the primary moment needs to be significantly increased to increase the received signal. To attain this a loop size with a side of 50 - 100 m is required.

Aboriginal and Torres Strait Islander people are advised that this website may contain the names, voices and images of people who have died, as well as other culturally sensitive content. Please be aware that some collection items may use outdated phrases or words which reflect the attitude of the creator at the time, and are now considered offensive.

We use temporary cookies on this site to provide functionality.
By continuing to use this site without changing your settings, you consent to our use of cookies.