5 months ago by Sian Evans
With our seismometers tested, kit assembled and training complete, we split into five teams and hit the road on a mission to find our first deployment sites. This turned out be easier for some than for others.
In order to acquire a detailed 3D image of the subsurface geology, our seismometers must be spaced roughly 2km apart in a grid across the Gisborne region. But choosing a deployment site is not as straightforward as it sounds.
Our 6TD instruments are made to detect even the smallest of ground movements associated with earthquake activity and are therefore super sensitive to noise such as road traffic rumbling, trees rustling, streams flowing, power lines buzzing, and even electric fences humming. And as the majority of the area is farmland, our biggest contender is the livestock itself. Not only will they generate noise as they amble about the field but curious cows may fancy a nibble on the cables and pull our seismometers out the ground! To combat this we build sturdy fences around our deployment sites.
As if that wasn't tricky enough in rural New Zealand we also have to ensure our solar panels get lots of light and our GPS has a good signal from the satellites. That means no hiding in the bushes. So you can see how finding the perfect spot may take a little time! In fact, our perseverance to hunt down the best deployment sites often means we're splashing through streams along bumpy offroad tracks, strapping our helmets on for a hair-raising ride in an LUV, or when all else fails lugging the equipment up a valley on foot. Our efforts paid off though. Let's just hope that fence holds!
Well, now we've chosen a perfect site, let's put a seismometer in the ground! Wondering what that looks like? Stay tuned...
And if you just can't wait, catch us on Twitter: @NZ3D_FWI