Field Deployment Guides

Version 25.2 by robert on 2025/06/15 14:26

Site selection and preparation

If possible, choose a location with minimal noise interference and as far away from traffic and people as possible. Try to keep your station out of site to avoid theft or tampering. The site should not be installed in a place where people would ever stumble upon it (e.g. a walking trail or public area).
Nearby Trees, bushes, power poles etc can induce low period noise in your data when they sway in the wind. A rule of thumb is to have your sensor at least as far away from these as their height.
Cattle and stock can and will destroy your site. NEVER EVER install a station where cows can get to it.
If the area looks like a place that has flooded, or may flood again, absolutely assume that it will. This very much includes dry riverbeds or ponds. Always prefer locally elevated terranes.
The harder the soil, the better the signal. Sand and mud are your enemy.

Grass can often grow high enough to block your solar panel from sun. If possible, clear an area in front of the panel to minimize this possibility.

Installing Sensors

Bury seismometers at an appropriate depth for noise reduction and stable ground coupling, typically 0.5-0.8 metre depth but deeper the better.
Ensure the sensor is leveled correctly, typically the sensor can be placed on a well leveled paver to make this easier.
Orient the sensor correctly using a compass, paying special attention to the north direction and accounting for declination.
- When using a compass to orient the sensors, ensure it is kept away from metal objects or structures that could interfere with its magnetic field.
- It is recommended to take a picture of the sensor's orientation next to the compass.
It is recommended that the following sensors be installed with a PVC tube covering to prevent corrosion and other environmental degradation:
- TC-120
- TC-20
- 3D lites
Hold the sensor or sensor covering securely while infilling and compacting the hole to ensure the setup is kept in the correct position (level and oriented).

Setting up Data Logger

Install data loggers or recorders compatible with the sensors.
Ensure adequate storage capacity and configuration for the desired sampling rate and data format. Generally:

64Gb card: 245 days @ 250hz or 610 days @ 100hz

32Gb card: 122 days @ 250hz or 305 days @ 100hz

Establish a reliable power source, such as solar panels, batteries, or local grid connection. Use a compass to align solar panels facing north in the southern hemisphere for optimal sunlight exposure.
Set up a GPS antenna to provide accurate time synchronization for the seismic data.
Ensure the GPS antenna has a clear view of the sky for optimal signal reception.
Calibrate sensors and data acquisition systems for accuracy.
Test for sensitivity, noise levels, and overall performance.
More information for logger setup can be found on the 'ANU Seismic Data Loggers' page.

Fire safety measures and documentation in seismic station installation

In bushfire-prone areas, clear a wide perimeter around the installation to reduce fire risk.
Use fireproof blankets to cover equipment, providing an additional layer of protection against fire damage.
Install a metal net over the entire setup to shield it from external elements

Document the installation process, including sensor types, orientations, locations, and system configurations, along with fire safety measures implemented.
Record essential metadata for seismic data interpretation.

Sensor protection

Sensors can be covered with a PVC pipe to help prevent degradation of the components (i.e. sensor casing and cable connections), however, some sensors are made for direct burial (no protection). When installing a sensor, only use these two options. Do not try to protect the sensor via any other means such as a plastic bag or moisture absorbers & desiccants.

DO NOT: bury the sensors with anything other than a PVC housing or direct burial. Other methods may damage the equipment more than protect it.

Step-by-step field installation guide (with images)

1. Dig a hole roughly 80cm deep and wide enough to place a paver in.	2. Level the bottom of the hole. A paver or brick can be used to create a flat base for the device. Draw a line on the paver, orient it towards North and level it.	3. Place the seismometer on the paver and ensure it is levelled and oriented (remember to account for the declination in your area).
4. Depending on the model of the seismometer, place a protective PVC tub over it.	5. Fill in the hole whilst stabilising the sensor and packing the dirt firmly.	6. Once the hole is filled and levelled, drive a stake (star pickets work well) into the ground next to the seismometer, and fit the wire panels over it, driving pegs into the north-facing side.
7. Attach the solar panel to this side, and the GPS to the stake (wrap the wire around the stake once or twice so it stays in position if it is detached).	8. Connect the seismometer, solar panel, and GPS to the logger and turn the logger on. See "setting up data logger" and "ANU seismic data loggers" page for more details. Set the logger to record and ensure it starts recording.	9. Cover the logger with a fire blanket, starting by placing it on the top, so the opening is underneath the logger.
10. Once all the sides of the blanket are tucked under the logger, cover the logger with rocks or dirt.	11. Fold the other metal grating panel over and peg it into the ground. If the ground is too hard, a wire can be used to fix the metal grates to each other. This will also help reduce noise from the rattle of the cage prevent animals from getting to the logger.	12. A completed site. Rocks and sticks can also be piled on the ends of the cage if there is a risk of animals tampering in the area.

Experimental Sand Burial:

Direct burials are used for Trillium Compact Postholes as they are specifically designed to be corrosion resistant. Other sensors such as the Trillum Compact 120, Trillum Compact 20, and 3D Lites are not built with this degree of corrosion resistance. Currently, the best prevention for moisture trapping and corrosion is burying them with a PVC covering. However, in particularly wet environments, some moisture can still collect within these coverings. One experimental method that is being trialled in hopes of providing better drainage is the sand burial. Steps 1, 2, and 3 remain the same, though once the sensor is set with the correct levelling and orientation, the subsequent infill steps differ. Once the open PVC tube is placed around the sensor, infill the hole around the tubing, holding it in place (image A). Once the hole is back-filled level with the tubing, securing it in place, begin filling the interior of the PVC tube with sand. Hold the sensor in place and ensure the sand is packed tightly around it (image B). Once the sand fills the PVC tube, gently remove the PVC tube while holding the sensor in place (pliers may be required to grip the tube). The last deviation for a sand burial from the standard burial is continuing to place some sand above the sensor, and dirt (or other local substrate around that sand pocket) until level with the surface (image C).