Response to Info Request - Attachment 5 - Geotechnical Report MCU18-0015 & RAL18-0001 · MCU18/0015

J000635-002-R-Rev1                                                                                                                           November 2018


Table 2: Seismic Data Acquisition Parameters.

Seismic source:                      10 kg sledgehammer on aluminium plate

                                     Geode-24 seismograph using Geometrics Seismodule Controller
Recording system:
                                     software; 24-bit 24-channel recorder

Recording channels:                  24 per record

Sampling rate:                       0.25 ms

Record length:                       2 seconds

Geophone type:                       4.5 Hz single geophones

Initial offset:                      12 m

Source interval:                     12 m

Geophone interval:                   1.5 m

The MASW seismic testing method provides a subsurface profile of seismic surface shear-wave velocities
(vs). When correlated with the borehole/test pit findings, the seismic wave velocities can be used to provide
an indication of changes in the subsurface profile along the alignment tested.
Results of the seismic testing were correlated with the available geotechnical data, our previous experience,
and published information.
Seismic survey results are presented as 2D cross sections in Figure 2, with a discussion of the results given
in Section 5.2.

5.0         INVESTIGATION FINDINGS
5.1       Geological Mapping
The Gympie Special Geology map 1 indicates that the site is located close to the contact between the
Pleistocene age quartz sand and Jurassic to Cretaceous aged quartz diorite. Image 1 shows an extract from
the geology map.




1 GYMPIE SPECIAL 1:100,000 Geological Series. Map Sheet 9445 and Part 9545, First Edition, Department of Mines and Energy, Brisbane, 1999.




                                                                                    4