This week I have been up in the Scottish Borders at the borehole site, it has been very exciting to see it all in action!
The progress to date is that we have passed the 100 metre mark. There have been some problems recently with fractures within sandstone units, which has delayed drilling while they have been in filled. Another issue has been that the hardness of the cementstones in the Ballagan Formation means that we need to use an especially tough drill bit. Due to the expertise of the drillers from Drillcorp we are overcoming these problems and drilling continues.
|Geology problem solving 1: solving the problem of fractures in the rock by grouting the borehole with a cement-based mixture.|
|Geology problem solving 2: using a harder drill bit to cut through cementstones.|
I examined the core and was surprised to find that you can identify the rock type through the plastic core liner, and even touch to rock to check grain size through the slit in the liner. The quality of the core that we have extracted so far is excellent! Dave Millward, Mike Browne and Tim Kearsey are logging the cores on site as they come out of the borehole. This gives us a provisional record and a good indication of where we are stratigraphically (the relative age of rock units).
An example of the core in its liner, you can see the different rock units due to their colour variation
There has been a lot of interest in the borehole, both nationally (see 8th April 2013 post ‘borehole drilling has started!’) and locally. Farmer and landowner of the borehole site Alistair Birkett has had many exciting discussions with the locals about palaeontology and evolution, while explaining why we are drilling the borehole. Thank you Alistair for making all this possible!
Landowner Alistair Birkett (centre) on site with me and Dave Millward
Also this week, Tim and I visited our autumn field locality again, to look at some palaeosols and cementstones in more detail and do a little more sampling. It was fantastic to experience some fieldwork in the sunshine, and I had a happy reunion with the Geology Cat who was still there playing on the beach!
Until next time