Sun, sand and sediment

Examining sand island sediment core

Examining sand island sediment core

In December we took a breather from cold weather operations and travelled to Fiji. Our role here was to obtain sediment samples from the bottom of a series of sand islands, in order to estimateĀ the dateĀ of island formation (700 to 800 years ago).

The islands were approximately 1 to 10 km off shore and we accessed them by either using a boat hired from the local village, or by stomping in across mud flats / estuaries, to access the more coastal islands.

We had a Livingstone Corer with us onto which we attached a battery-powered concrete vibrator to allow us to penetrate the coarse shell-rich sand. We managed to penetrate the sand OK, but extracting the coarse surface sediment was another matter. The coarseness and low density of the material meant that reliable extraction using the Livingstone was not easily achievable and after an afternoon of testing we resolved that other methods would need to be employed.

Fortunately, I rarely travel without my trusty snow shovel and within an hour or two, we’d dug four pits to the water level. With further digging at low tide and then use of the Livingstone we were able to hit the coral/sediment interface and obtain numerous interface samples for later carbon dating.

In this case, although things didn’t initially work out as expected, we had the tools and the ‘can do’ attitude to ensure that the work was safely and successfully completed, on numerous islands, within the desired time frame.

Interested in the pursuit of remote area science & engineering, and the empowerment of people...

Leave a Reply


captcha *