Saturday, November 29, 2014

DFDP-2 @ 635 m, packer tool

Rupert Sutherland, GNS Science and Victoria University of Wellington
John Townend, Victoria University of Wellington
Virginia Toy, University of Otago

Doug Schmitt, Dierdre Mallyon, and Alex Pyne take a moment from packer tool testing. 28/11/14. Photo B. Celerier. 

Drilling has been going smoothly over the last few days. We reached 635 m depth at breakfast time. 

We will continue this phase of drilling until the team analysing rock cuttings tell us we are near the fault. Then, we will put steel casing (pipe) into the hole and cement the annulus (gap between rock and steel), to secure a foundation for deeper operations.

In the meantime, we are also mobilising and testing tools for the next phase. A new tool for imaging the borehole wall at high temperatures arrived this morning from Europe, and a packer tool was tested on site.


Water circulating through packer tool. Photo B. Celerier.

A packer is a rubber element that inflates to seal and isolate a section of the borehole. It is then possible to pump water down the pipe that is inside the packer and inject water into the isolated section of rock. The process works in reverse too: you can produce a small amount of fluid out of the rock from an isolated section of borehole.

Why do we want to do packer experiments? 
(1) To determine how easily fluid can move through the rock; and 
(2) to collect fluid for analysis. 
When combined with other data, we can also use this tool to evaluate the stress state of the rock, which is interesting for us earthquake scientists.

Checking the packer tool works OK. Photo B. Celerier.

Primary funders of the DFDP-2 project are: the International Continental Scientific Drilling Program (ICDP), the Marsden Fund of the Royal Society of New Zealand, GNS Science, Victoria University of Wellington, and the University of Otago.